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1.
Physiol Rev ; 99(2): 1079-1151, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30672368

RESUMEN

Acute pain signaling has a key protective role and is highly evolutionarily conserved. Chronic pain, however, is maladaptive, occurring as a consequence of injury and disease, and is associated with sensitization of the somatosensory nervous system. Primary sensory neurons are involved in both of these processes, and the recent advances in understanding sensory transduction and human genetics are the focus of this review. Voltage-gated sodium channels (VGSCs) are important determinants of sensory neuron excitability: they are essential for the initial transduction of sensory stimuli, the electrogenesis of the action potential, and neurotransmitter release from sensory neuron terminals. Nav1.1, Nav1.6, Nav1.7, Nav1.8, and Nav1.9 are all expressed by adult sensory neurons. The biophysical characteristics of these channels, as well as their unique expression patterns within subtypes of sensory neurons, define their functional role in pain signaling. Changes in the expression of VGSCs, as well as posttranslational modifications, contribute to the sensitization of sensory neurons in chronic pain states. Furthermore, gene variants in Nav1.7, Nav1.8, and Nav1.9 have now been linked to human Mendelian pain disorders and more recently to common pain disorders such as small-fiber neuropathy. Chronic pain affects one in five of the general population. Given the poor efficacy of current analgesics, the selective expression of particular VGSCs in sensory neurons makes these attractive targets for drug discovery. The increasing availability of gene sequencing, combined with structural modeling and electrophysiological analysis of gene variants, also provides the opportunity to better target existing therapies in a personalized manner.


Asunto(s)
Dolor Crónico/metabolismo , Umbral del Dolor , Células Receptoras Sensoriales/metabolismo , Canales de Sodio Activados por Voltaje/metabolismo , Analgésicos/uso terapéutico , Animales , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/genética , Dolor Crónico/fisiopatología , Diseño de Fármacos , Humanos , Umbral del Dolor/efectos de los fármacos , Células Receptoras Sensoriales/efectos de los fármacos , Transducción de Señal , Bloqueadores del Canal de Sodio Activado por Voltaje/uso terapéutico , Canales de Sodio Activados por Voltaje/efectos de los fármacos , Canales de Sodio Activados por Voltaje/genética
2.
Brain ; 147(9): 3157-3170, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38447953

RESUMEN

Vincristine-induced peripheral neuropathy is a common side effect of vincristine treatment, which is accompanied by pain and can be dose-limiting. The molecular mechanisms that underlie vincristine-induced pain are not well understood. We have established an animal model to investigate pathophysiological mechanisms of vincristine-induced pain. Our previous studies have shown that the tetrodotoxin-sensitive voltage-gated sodium channel Nav1.6 in medium-diameter dorsal root ganglion (DRG) neurons contributes to the maintenance of vincristine-induced allodynia. In this study, we investigated the effects of vincristine administration on excitability in small-diameter DRG neurons and whether the tetrodotoxin-resistant (TTX-R) Nav1.8 channels contribute to mechanical allodynia. Current-clamp recordings demonstrated that small DRG neurons become hyper-excitable following vincristine treatment, with both reduced current threshold and increased firing frequency. Using voltage-clamp recordings in small DRG neurons, we now show an increase in TTX-R current density and a -7.3 mV hyperpolarizing shift in the half-maximal potential (V1/2) of activation of Nav1.8 channels in vincristine-treated animals, which likely contributes to the hyperexcitability that we observed in these neurons. Notably, vincristine treatment did not enhance excitability of small DRG neurons from Nav1.8 knockout mice, and the development of mechanical allodynia was delayed but not abrogated in these mice. Together, our data suggest that sodium channel Nav1.8 in small DRG neurons contributes to the development of vincristine-induced mechanical allodynia.


Asunto(s)
Ganglios Espinales , Hiperalgesia , Canal de Sodio Activado por Voltaje NAV1.8 , Neuronas , Vincristina , Animales , Vincristina/toxicidad , Vincristina/farmacología , Ganglios Espinales/metabolismo , Ganglios Espinales/efectos de los fármacos , Canal de Sodio Activado por Voltaje NAV1.8/metabolismo , Canal de Sodio Activado por Voltaje NAV1.8/genética , Hiperalgesia/inducido químicamente , Hiperalgesia/metabolismo , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Masculino , Ratones Noqueados , Tetrodotoxina/farmacología , Potenciales de Acción/efectos de los fármacos , Ratones Endogámicos C57BL , Antineoplásicos Fitogénicos/toxicidad , Técnicas de Placa-Clamp
3.
Small ; : e2406576, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39363674

RESUMEN

Graphitic carbon nitride (gC3N4) is an attractive photocatalyst for solar energy conversion due to its unique electronic structure and chemical stability. However, gC3N4 generally suffers from insufficient light absorption and rapid compounding of photogenerated charges. The introduction of defects and atomic doping can optimize the electronic structure of gC3N4 and improve the light absorption and carrier separation efficiency. Herein, the high efficiency of carbon nitride photocatalysis for hydrogen evolution in visible light is achieved by an S-modified double-deficient site strategy. Defect engineering forms abundant unsaturated sites and cyano (─C≡N), which promotes strong interlayer C─N bonding interactions and accelerates charge transport in gC3N4. S doping tunes the electronic structure of the semiconductors, and the formation of C─S─C bonds optimizes the electron-transfer paths of the C─N bonding, which enhances the absorption of visible light. Meanwhile,C≡N acts as an electron trap to capture photoexcited electrons, providing the active site for the reduction of H+ to hydrogen. The photocatalytic hydrogen evolution efficiency of SDCN (1613.5 µmol g-1 h-1) is 31.5 times higher than that of pristine MCN (51.2 µmol g-1 h-1). The charge separation situation and charge transfer mechanism of the photocatalysts are investigated in detail by a combination of experimental and theoretical calculations.

4.
J Med Virol ; 96(3): e29542, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38506170

RESUMEN

The emerging new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) needs booster vaccination. We evaluated the long-term safety and immunogenicity of heterologous boosting with a SARS-CoV-2 messenger RNA vaccine SYS6006. A total of 1000 participants aged 18 years or more who had received two (Group A) or three (Group B) doses of SARS-CoV-2 inactivated vaccine were enrolled and vaccinated with one dose of SYS6006 which was designed based on the prototype spike protein and introduced mutation sites. Adverse events (AEs) through 30 days and serious AEs during the study were collected. Live-virus and pseudovirus neutralizing antibody (Nab), binding antibody (immunoglobulin G [IgG]) and cellular immunity were tested through 180 days. Solicited all, injection-site and systemic AEs were reported by 618 (61.8%), 498 (49.8%), and 386 (38.6%) participants, respectively. Most AEs were grade 1. The two groups had similar safety profile. No vaccination-related SAEs were reported. Robust wild-type (WT) live-virus Nab response was elicited with peak geometric mean titers (GMTs) of 3769.5 (Group A) and 5994.7 (Group B) on day 14, corresponding to 1602.5- and 290.8-fold increase versus baseline, respectively. The BA.5 live-virus Nab GMTs were 87.7 (Group A) and 93.2 (Group B) on day 14. All participants seroconverted for WT live-virus Nab. Robust pseudovirus Nab and IgG responses to wild type and BA.5 were also elicited. ELISpot assay showed robust cellular immune response, which was not obviously affected by virus variation. In conclusion, SYS6006 heterologous boosting demonstrated long-term good safety and immunogenicity in participants who had received two or three doses of SARS-CoV-2 inactivated vaccine.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Inmunogenicidad Vacunal , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , China , COVID-19/prevención & control , Inmunoglobulina G , Vacunas de ARNm , Vacunas de Productos Inactivados
5.
Br J Clin Pharmacol ; 90(1): 247-263, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37574850

RESUMEN

AIMS: Abiraterone acetate, a prodrug of abiraterone (ABI), provides an efficient therapeutic option for metastatic castration-resistant prostate cancer patients. ABI undergoes extensive metabolism in vivo and is transformed into active metabolites Δ4 -abiraterone and 3-keto-5α-abiraterone as well as inactive metabolites abiraterone sulfate and abiraterone N-oxide sulfate. We aimed to examine the effect of polymorphisms in SLCO2B1, CYP3A4 and UGT1A4 on the pharmacokinetics of ABI and its metabolites. METHODS: In this study, 81 healthy Chinese subjects were enrolled and divided into 2 groups for fasted (n = 45) and fed (n = 36) studies. Plasma samples were collected after administering a 250 mg abiraterone acetate tablet followed by liquid chromatography-tandem mass spectrometry analysis. Genotyping was performed on a MassARRAY system. The association between SLCO2B1, CYP3A4, UGT1A4 genotype and pharmacokinetic parameters of ABI and its metabolites was assessed. RESULTS: Food effect study demonstrated high fat meal remarkedly increased systemic exposure of ABI and its metabolites. The geometric mean ratio and 90% confidence interval of area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration (AUC0-t ) and maximum plasma concentration (Cmax ) of ABI in fed state vs. fasted state were 351.64% (286.86%-431.04%) and 478.45% (390.01%-586.94%), respectively, while the corresponding results were ranging from 145.11% to 269.42% and 150.10% to 478.45% for AUC0-t and Cmax of ABI metabolites in fed state vs. fasted state, respectively. The SLCO2B1 rs1077858 had a significant influence on AUC0-t and Cmax , while 7 other SLCO2B1 variants prolonged half-life of ABI under both fasted and fed conditions. As for ABI metabolites, the systemic exposure of Δ4 -abiraterone, abiraterone sulfate and abiraterone N-oxide sulfate as well as the elimination of 3-keto-5α-abiraterone were significantly affected by SLCO2B1 polymorphisms. Polymorphisms in CYP3A4 and UGT1A4 did not significantly affect pharmacokinetics of ABI and its metabolites. CONCLUSION: Polymorphisms in SLCO2B1 were significantly related to the pharmacokinetic variability of ABI and its metabolites under both fasted and fed conditions.


Asunto(s)
Androstenos , Citocromo P-450 CYP3A , Transportadores de Anión Orgánico , Farmacocinética , Androstenos/metabolismo , Androstenos/farmacocinética , Humanos , Transportadores de Anión Orgánico/genética , Citocromo P-450 CYP3A/genética , Glucuronosiltransferasa/genética , Neoplasias de la Próstata , Polimorfismo de Nucleótido Simple , Pueblos del Este de Asia , Masculino , Voluntarios , Adulto , Ayuno , Alimentos
6.
Environ Sci Technol ; 58(39): 17376-17385, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39305248

RESUMEN

The membrane fouling derived from the accumulated dust pollutants and highly viscous oily particles causes irreversible damage to the filtration performance of air filters and results in a significant reduction in their service life. However, it is still challenging to construct high-efficiency and antifouling air filtration membranes with recyclable regeneration. Herein, the fluorine-free amphiphobic micro/nanofiber composite membrane was controllably constructed by integrating click chemistry reaction and electrospinning technique. Low-surface-energy fibers were constructed by a thiol-ene click chemical reaction between mercaptosilane and vinyl groups of polystyrene-butadiene-styrene (SBS), combined with hydroxyl-terminated poly(dimethylsiloxane) during the electrospinning process. The functional air filter is then prepared by the two-layer composite strategy. Because of the advantages of liquid-like fibrous surface and micro/nanofibrous porous structure, SBS/PAN composite membrane simultaneously shows superior antifouling performances of pollutants and filtration efficiency of over 97% PM0.3 removal. More importantly, the antifouling fibrous membrane still presents a stable and efficient filtration efficiency after multiple washes. Its service life in dust filtration environments is approximately 1.7 times longer than that of the substrate membrane. This work may provide a significant reference for the design of antifouling fiber membranes and high-efficiency air filters with long life spans and reusability.


Asunto(s)
Membranas Artificiales , Nanofibras , Nanofibras/química , Filtración , Filtros de Aire , Química Clic , Flúor/química
7.
Chem Soc Rev ; 52(2): 473-509, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36484322

RESUMEN

Hydrogel-based conductive materials for smart wearable devices have attracted increasing attention due to their excellent flexibility, versatility, and outstanding biocompatibility. This review presents the recent advances in multifunctional conductive hydrogels for electronic devices. First, conductive hydrogels with different components are discussed, including pure single network hydrogels based on conductive polymers, single network hydrogels with additional conductive additives (i.e., nanoparticles, nanowires, and nanosheets), double network hydrogels based on conductive polymers, and double network hydrogels with additional conductive additives. Second, conductive hydrogels with a variety of functionalities, including self-healing, super toughness, self-growing, adhesive, anti-swelling, antibacterial, structural color, hydrophobic, anti-freezing, shape memory and external stimulus responsiveness are introduced in detail. Third, the applications of hydrogels in flexible devices are illustrated (i.e., strain sensors, supercapacitors, touch panels, triboelectric nanogenerator, bioelectronic devices, and robot). Next, the current challenges facing hydrogels are summarized. Finally, an imaginative but reasonable outlook is given, which aims to drive further development in the future.

8.
Electrophoresis ; 44(1-2): 82-88, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36031791

RESUMEN

Precise cell detecting and counting is meaningful in circulating tumor cells (CTCs) analysis. In this work, a simple cyclic olefin copolymer (COC) microflow cytometer device was developed for size-resolved CTCs counting. The proposed device is constructed by a counting channel and a pinched injection unit having three channels. Through injection flow rate control, microspheres/cells can be focused into the centerline of the counting channel. Polystyrene microspheres of 3, 9, 15, and 20 µm were used for the microspheres focusing characterization. After coupling to laser-induced fluorescence detection technique, the proposed device was used for polystyrene microspheres counting and sizing. A count accuracy up to 97.6% was obtained for microspheres. Moreover, the proposed microflow cytometer was applied to CTCs detecting and counting. To mimic blood sample containing CTCs and CTCs mixture with different subtypes, an MDA-MB-231 (human breast cell line) spiked red blood cells sample and a mixture of MDA-MB-231 and MCF-7 (human breast cell line) sample were prepared, respectively, and then analyzed by the developed pinched flow-based microfluidic cytometry. The simple fabricated and easy operating COC microflow cytometer exhibits the potential in the point-of-care clinical application.


Asunto(s)
Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Humanos , Microfluídica/métodos , Células Neoplásicas Circulantes/patología , Poliestirenos , Citometría de Flujo , Eritrocitos/patología , Línea Celular Tumoral , Separación Celular/métodos
9.
Int Microbiol ; 26(1): 59-68, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35953617

RESUMEN

An increasing number of infections caused by multidrug-resistant (MDR) Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) have severely affected human society. Thus, it is essential to develop an alternative type of antibacterial agents that has a different bacterial resistance mechanism from that of traditional antibiotics. After the synthesis and structural characterization of a cationic pillar[5]arene with pyridinium groups (PP5), the antibacterial and antibiofilm activities as well as its microbial resistance were systematically investigated. In-depth evaluation of biological studies revealed that PP5 was an active antibacterial agent, with surprising antibiofilm formation ability against E. coli and S. aureus. From the results of differential scanning calorimetry and transmission electron microscopy, it was concluded that the microbicidal activity of PP5 was due to the physical disruption of the pathogen's membrane and the subsequent leakage of cytoplasmic components, which could greatly reduce the rapid generation of resistance. It was presented that the easily available PP5 has high activity to inhibit Gram-positive and Gram-negative bacteria and/or their biofilms with low cytotoxicity. This pillar[5]arene derivative can be used as a good candidate for controlling drug-resistant pathogenic bacterial infections and treating MDR bacteria.


Asunto(s)
Antibacterianos , Infecciones Estafilocócicas , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus , Escherichia coli , Farmacorresistencia Bacteriana , Bacterias Gramnegativas , Bacterias Grampositivas , Biopelículas , Pruebas de Sensibilidad Microbiana
10.
Br J Clin Pharmacol ; 89(12): 3659-3668, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37464978

RESUMEN

AIMS: This study evaluated the effects of SHR0302 on the pharmacokinetics of cytochrome P450 (CYP) probe substrates. METHODS: We performed a single-centre, open-label, three-period drug-drug interaction (DDI) study in 24 healthy subjects (NCT05392127). Subjects received a single oral dose of 5 mg warfarin (CYP2C9), 20 mg omeprazole (CYP2C19) and 15 mg midazolam (CYP3A4) on Days 1, 8 and 22, and received 0.5 mg repaglinide (CYP2C8) on Days 7, 14 and 28. Multiple oral doses of 8 mg SHR0302 were administered once daily from Day 8 to Day 28. RESULTS: The exposure of S-warfarin and repaglinide were comparable before and after SHR0302 administration. AUC of midazolam was not affected by SHR0302, whereas the administration of SHR0302 slightly decreased the Cmax of midazolam by 7.6% (single dose) and 15.7% (once daily for 14 days). The AUC0-t , AUC0-inf , and Cmax of omeprazole were slightly decreased after a single dose of SHR0302 by 19.2%, 21.8% and 23.5%, respectively. In the presence of SHR0302 for 14 days, the AUC0-t , AUC0-inf , and Cmax of omeprazole were marginally reduced by 3.0%, 16.4% and 8.3%, respectively. According to the induction mechanism of the CYP enzyme, for the investigation of the induction effect, the results of multiple administrations of the perpetrator were more reliable than those of the single dose. CONCLUSIONS: The results demonstrated that co-administration of SHR0302 8 mg once daily is unlikely to have a clinically meaningful effect on the exposure of drugs metabolized by CYP3A4, CYP2C8, CYP2C9 and CYP2C19 in healthy subjects.


Asunto(s)
Citocromo P-450 CYP3A , Midazolam , Humanos , Citocromo P-450 CYP3A/metabolismo , Midazolam/farmacocinética , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP2C9 , Warfarina , Citocromo P-450 CYP2C19/genética , Interacciones Farmacológicas , Sistema Enzimático del Citocromo P-450/metabolismo , Omeprazol/farmacocinética , Voluntarios Sanos
11.
Parasitology ; 150(6): 531-544, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37051887

RESUMEN

Cryptosporidium spp. are significant opportunistic pathogens causing diarrhoea in humans and animals. Pigs are one of the most important potential hosts for Cryptosporidium. We evaluated the prevalence of Cryptosporidium in pigs globally using published information and a random-effects model. In total, 131 datasets from 36 countries were included in the final quantitative analysis. The global prevalence of Cryptosporidium in pigs was 16.3% (8560/64 809; 95% confidence interval [CI] 15.0­17.6%). The highest prevalence of Cryptosporidium in pigs was 40.8% (478/1271) in Africa. Post-weaned pigs had a significantly higher prevalence (25.8%; 2739/11 824) than pre-weaned, fattening and adult pigs. The prevalence of Cryptosporidium was higher in pigs with no diarrhoea (12.2%; 371/3501) than in pigs that had diarrhoea (8.0%; 348/4874). Seven Cryptosporidium species (Cryptosporidium scrofarum, Cryptosporidium suis, Cryptosporidium parvum, Cryptosporidium muris, Cryptosporidium tyzzeri, Cryptosporidium andersoni and Cryptosporidium struthioni) were detected in pigs globally. The proportion of C. scrofarum was 34.3% (1491/4351); the proportion of C. suis was 31.8% (1385/4351) and the proportion of C. parvum was 2.3% (98/4351). The influence of different geographic factors (latitude, longitude, mean yearly temperature, mean yearly relative humidity and mean yearly precipitation) on the infection rate of Cryptosporidium in pigs was also analysed. The results indicate that C. suis is the dominant species in pre-weaned pigs, while C. scrofarum is the dominant species in fattening and adult pigs. The findings highlight the role of pigs as possible potential hosts of zoonotic cryptosporidiosis and the need for additional studies on the prevalence, transmission and control of Cryptosporidium in pigs.


Asunto(s)
Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Enfermedades de los Porcinos , Porcinos , Animales , Humanos , Criptosporidiosis/epidemiología , Prevalencia , Enfermedades de los Porcinos/epidemiología , Heces , Genotipo
12.
J Environ Manage ; 331: 117338, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36696760

RESUMEN

In recent years, the global warming trend is still increasing due to CO2 emissions from various sources, such as electricity, heat production, industry, and transportation. In the vanadium industry, the vanadium bearing shale is of low grade, and the extraction of the required elemental vanadium produces large quantities of vanadium tailings (VTs). Both the roasting pretreatment of vanadium shale during vanadium extraction and the high-temperature calcination process for the preparation of vanadium products generate large amounts of CO2 gas. Therefore, it is particularly important to find an effective and environmentally friendly method for the treatment of vanadium tailings and CO2 generated by the vanadium industry. In this study, a potential method for the indirect carbonation of low calcium VTs under atmospheric pressure conditions was investigated. The carbonation reaction was investigated for different ammonia addition factors and different introduced CO2 concentrations and temperatures. The carbonation experiments showed that under the conditions of coefficient of ammonia addition of 1.4, reaction time of 60 min and reaction temperature of 60 °C, the utilization rate of calcium in VTs reached 97.9% and the CO2 uptake of VTs at 0.073 g-CO2/g, indicating that the carbonation of vanadium with low-calcium VTs was effective. The carbonation product was analyzed and measured using TG, XRD, and SEM-EDS, and it was discovered to be CaCO3, confirming the feasibility of carbonation reaction with vanadium tailings. Furthermore, the characterization of the carbonation product confirmed the mechanism and safety of the carbonation reaction, laying the groundwork for future applications.


Asunto(s)
Carbono , Vanadio , Dióxido de Carbono , Calcio , Amoníaco , Minerales , Carbonatos , Secuestro de Carbono
13.
Parasitology ; 149(12): 1652-1665, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36073170

RESUMEN

Cryptosporidium spp. are important pathogens with some species causing diarrhoea in humans and animals. Sheep are one of the most common potential hosts for various Cryptosporidium spp. The prevalence of Cryptosporidium in sheep globally was evaluated from published information including molecular data via meta-analysis. In total, 126 datasets from 41 countries were included for final quantitative analysis. Sheep aged <3 months had a significantly higher prevalence (27.8%; 3284/11 938) than those at the age of 3­12 and >12 months. The prevalence of Cryptosporidium in sheep with diarrhoea of 35.4% (844/1915) was higher than in sheep that did not show diarrhoea (11.3%; 176/1691). Fourteen Cryptosporidium species/genotypes were detected in sheep globally. The proportion of subgenotype family XIIa of Cryptosporidium ubiquitum was 90.0% (216/240); the proportions of subgenotypes IIdA20G1 and IIaA15G2R1 of Cryptosporidium parvum were 15.4% (62/402) and 19.7% (79/402). The results indicate that C. parvum is the dominant species in Europe while Cryptosporidium xiaoi is the dominant species in Oceania, Asia and Africa and C. ubiquitum is the dominant species in North America and South America. Subgenotype family IIa of C. parvum is particularly widespread among sheep worldwide. The results highlight the role of sheep as a reservoir host for zoonotic cryptosporidia and the need for further study of prevalence, transmission and control of this pathogen in sheep.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Enfermedades de las Ovejas , Humanos , Ovinos , Animales , Cryptosporidium/genética , Criptosporidiosis/epidemiología , Prevalencia , Enfermedades de las Ovejas/epidemiología , Genotipo , Diarrea/epidemiología , Diarrea/veterinaria , Heces
14.
J Biol Chem ; 295(4): 1077-1090, 2020 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-31822564

RESUMEN

Genetic and functional studies have confirmed an important role for the voltage-gated sodium channel Nav1.9 in human pain disorders. However, low functional expression of Nav1.9 in heterologous systems (e.g. in human embryonic kidney 293 (HEK293) cells) has hampered studies of its biophysical and pharmacological properties and the development of high-throughput assays for drug development targeting this channel. The mechanistic basis for the low level of Nav1.9 currents in heterologous expression systems is not understood. Here, we implemented a multidisciplinary approach to investigate the mechanisms that govern functional Nav1.9 expression. Recombinant expression of a series of Nav1.9-Nav1.7 C-terminal chimeras in HEK293 cells identified a 49-amino-acid-long motif in the C terminus of the two channels that regulates expression levels of these chimeras. We confirmed the critical role of this motif in the context of a full-length channel chimera, Nav1.9-Ct49aaNav1.7, which displayed significantly increased current density in HEK293 cells while largely retaining the characteristic Nav1.9-gating properties. High-resolution live microscopy indicated that the newly identified C-terminal motif dramatically increases the number of channels on the plasma membrane of HEK293 cells. Molecular modeling results suggested that this motif is exposed on the cytoplasmic face of the folded C terminus, where it might interact with other channel partners. These findings reveal that a 49-residue-long motif in Nav1.9 regulates channel trafficking to the plasma membrane.


Asunto(s)
Membrana Celular/metabolismo , Canal de Sodio Activado por Voltaje NAV1.9/química , Canal de Sodio Activado por Voltaje NAV1.9/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Citosol/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Activación del Canal Iónico , Cinética , Canal de Sodio Activado por Voltaje NAV1.7/química , Canal de Sodio Activado por Voltaje NAV1.7/metabolismo , Dominios Proteicos , Transporte de Proteínas , Relación Estructura-Actividad
15.
Lancet ; 396(10249): 479-488, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32702299

RESUMEN

BACKGROUND: This is the first randomised controlled trial for assessment of the immunogenicity and safety of a candidate non-replicating adenovirus type-5 (Ad5)-vectored COVID-19 vaccine, aiming to determine an appropriate dose of the candidate vaccine for an efficacy study. METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial of the Ad5-vectored COVID-19 vaccine was done in a single centre in Wuhan, China. Healthy adults aged 18 years or older, who were HIV-negative and previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-free, were eligible to participate and were randomly assigned to receive the vaccine at a dose of 1 × 1011 viral particles per mL or 5 × 1010 viral particles per mL, or placebo. Investigators allocated participants at a ratio of 2:1:1 to receive a single injection intramuscularly in the arm. The randomisation list (block size 4) was generated by an independent statistician. Participants, investigators, and staff undertaking laboratory analyses were masked to group allocation. The primary endpoints for immunogenicity were the geometric mean titres (GMTs) of specific ELISA antibody responses to the receptor binding domain (RBD) and neutralising antibody responses at day 28. The primary endpoint for safety evaluation was the incidence of adverse reactions within 14 days. All recruited participants who received at least one dose were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, NCT04341389. FINDINGS: 603 volunteers were recruited and screened for eligibility between April 11 and 16, 2020. 508 eligible participants (50% male; mean age 39·7 years, SD 12·5) consented to participate in the trial and were randomly assigned to receive the vaccine (1 × 1011 viral particles n=253; 5 × 1010 viral particles n=129) or placebo (n=126). In the 1 × 1011 and 5 × 1010 viral particles dose groups, the RBD-specific ELISA antibodies peaked at 656·5 (95% CI 575·2-749·2) and 571·0 (467·6-697·3), with seroconversion rates at 96% (95% CI 93-98) and 97% (92-99), respectively, at day 28. Both doses of the vaccine induced significant neutralising antibody responses to live SARS-CoV-2, with GMTs of 19·5 (95% CI 16·8-22·7) and 18·3 (14·4-23·3) in participants receiving 1 × 1011 and 5 × 1010 viral particles, respectively. Specific interferon γ enzyme-linked immunospot assay responses post vaccination were observed in 227 (90%, 95% CI 85-93) of 253 and 113 (88%, 81-92) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Solicited adverse reactions were reported by 183 (72%) of 253 and 96 (74%) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Severe adverse reactions were reported by 24 (9%) participants in the 1 × 1011 viral particles dose group and one (1%) participant in the 5 × 1010 viral particles dose group. No serious adverse reactions were documented. INTERPRETATION: The Ad5-vectored COVID-19 vaccine at 5 × 1010 viral particles is safe, and induced significant immune responses in the majority of recipients after a single immunisation. FUNDING: National Key R&D Programme of China, National Science and Technology Major Project, and CanSino Biologics.


Asunto(s)
Betacoronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Neumonía Viral/prevención & control , Vacunas Virales/efectos adversos , Vacunas Virales/inmunología , Adenoviridae , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19 , Vacunas contra la COVID-19 , China , Infecciones por Coronavirus/inmunología , Método Doble Ciego , Femenino , Vectores Genéticos , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T/inmunología , Vacunas Virales/administración & dosificación , Adulto Joven
16.
Brain ; 143(8): 2421-2436, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32830219

RESUMEN

Vincristine, a widely used chemotherapeutic agent, produces painful peripheral neuropathy. The underlying mechanisms are not well understood. In this study, we investigated whether voltage-gated sodium channels are involved in the development of vincristine-induced neuropathy. We established a mouse model in which repeated systemic vincristine treatment results in the development of significant mechanical allodynia. Histological examinations did not reveal major structural changes at proximal sciatic nerve branches or distal toe nerve fascicles at the vincristine dose used in this study. Immunohistochemical studies and in vivo two-photon imaging confirmed that there is no significant change in density or morphology of intra-epidermal nerve terminals throughout the course of vincristine treatment. These observations suggest that nerve degeneration is not a prerequisite of vincristine-induced mechanical allodynia in this model. We also provided the first detailed characterization of tetrodotoxin-sensitive (TTX-S) and resistant (TTX-R) sodium currents in dorsal root ganglion neurons following vincristine treatment. Accompanying the behavioural hyperalgesia phenotype, voltage-clamp recordings of small and medium dorsal root ganglion neurons from vincristine-treated animals revealed a significant upregulation of TTX-S Na+ current in medium but not small neurons. The increase in TTX-S Na+ current density is likely mediated by Nav1.6, because in the absence of Nav1.6 channels, vincristine failed to alter TTX-S Na+ current density in medium dorsal root ganglion neurons and, importantly, mechanical allodynia was significantly attenuated in conditional Nav1.6 knockout mice. Our data show that TTX-S sodium channel Nav1.6 is involved in the functional changes of dorsal root ganglion neurons following vincristine treatment and it contributes to the maintenance of vincristine-induced mechanical allodynia.


Asunto(s)
Antineoplásicos Fitogénicos/toxicidad , Hiperalgesia/inducido químicamente , Hiperalgesia/metabolismo , Canal de Sodio Activado por Voltaje NAV1.6/metabolismo , Células Receptoras Sensoriales/metabolismo , Vincristina/toxicidad , Animales , Femenino , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/metabolismo , Células Receptoras Sensoriales/efectos de los fármacos
17.
Parasitol Res ; 120(1): 73-81, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33191445

RESUMEN

Twenty-four fecal samples were collected from captive amur hedgehogs (Erinaceus amurensis) in Zhengzhou, China. Based on morphological and molecular analysis, the overall prevalence of Cystoisospora was 62.5% (15/24). These samples contained two types of coccidian oocysts, including C. rastegaievae (50.0%, 12/24) and a new species named C. yuensis n. sp. (12.5%, 3/24). Sporulated oocysts (n = 30) of C. yuensis n. sp. are ovoid, (20.6 ± 1.4) µm × (20.9 ± 0.9) µm, with a shape index (length/width) of 1.0 and a smooth and bi-layered oocyst wall, 1.3 µm thick (outer layer 0.8 µm, inner 0.5 µm). A polar granule is present, but micropyle cap, micropyle, and oocyst residuum are absent. The sporocysts are ovoid-shaped, (9.3 ± 0.6) µm × (8.5 ± 1.1) µm, with a shape index (length/width) of 1.1. Stieda, substieda bodies, and refractile bodies are absent. Residuum is scattered and distributed around the entire sporocysts. At the 18S rRNA locus, C. yuensis n. sp. exhibited the highest identity to C. timoni (99.3%) from a slender-tailed meerkat. It has 98.0% identity at the 28S rRNA locus and 99.3% at the ITS locus. Based on morphological and molecular data, this isolate is a new species of Cystoisospora. Additionally, we have provided data on the prevalence of C. rastegaievae in China and sequences of the 18S rRNS, 28S rRNA, and ITS loci.


Asunto(s)
Coccidiosis/veterinaria , Erizos/parasitología , Sarcocystidae/clasificación , Sarcocystidae/genética , Animales , China/epidemiología , Coccidiosis/epidemiología , Coccidiosis/parasitología , Complejo IV de Transporte de Electrones/genética , Heces/parasitología , Oocistos/clasificación , Filogenia , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Sarcocystidae/aislamiento & purificación
18.
Small ; 16(30): e2002094, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32529784

RESUMEN

Silicon anode with extremely high theoretical specific capacity (≈4200 mAh g-1 ), experiences huge volume changes during Li-ion insertion and extraction, causing mechanical fracture of Si particles and the growth of a solid-electrolyte interface (SEI), which results in a rapid capacity fading of Si electrodes. Herein, a mechanically reinforced localized structure is designed for carbon-coated Si nanoparticles (C@Si) via elongated TiO2 nanotubes networks toward stabilizing Si electrode via alleviating mechanical strain and stabilizing the SEI layer. Benefited from the rational localized structure design, the carbon-coated Si nanoparticles/TiO2 nanotubes composited electrode (C@Si/TiNT) exhibits an ideal electrode thickness swelling, which is lower than 1% after the first cycle and increases to about 6.6% even after 1600 cycles. While for traditional C@Si/carbon nanotube composited electrode, the initial swelling ratio is about 16.7% and reaches ≈190% after 1600 cycles. As a result, the C@Si/TiNT electrode exhibits an outstanding capacity of 1510 mAh g-1 at 0.1 A g-1 with high rate capability and long-time cycling performance with 95% capacity retention after 1600 cycles. The rational design on mechanically reinforced localized structure for silicon electrode will provide a versatile platform to solve the current bottlenecks for other alloyed-type electrode materials with large volume expansion toward practical applications.

19.
Small ; 16(8): e1907029, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31984658

RESUMEN

Sluggish kinetics of the multielectron transfer process is still a bottleneck for efficient oxygen evolution reaction (OER) activity, and the reduction of reaction overpotential is crucial to boost reaction kinetics. Herein, a correlation between the OER overpotential and the cobalt-based electrode composition in a "Microparticles-in-Spider Web" (MSW) superstructure electrode is revealed. The overpotential is dramatically decreased first and then slightly increased with the continuous increase ratio of Co/Co3 O4 in the cobalt-based composite electrode, corresponding to the dynamic change of electrochemically active surface area and charge-transfer resistance with the electrode composition. As a proof-of-concept, the optimized electrode displays a low overpotential of 260 mV at 10.0 mA cm-2 in alkaline conditions with a long-time stability. This electrochemical performance is comparable and even superior to the most currently reported Co-based OER electrocatalysts. The remarkable electrocatalytic activity is attributed to the optimization of the electrochemically active sites and electron transfer in the MSW superstructure. Theoretical calculations identify that the metallic Co and Co3 O4 surface catalytic sites play a vital role in improving electron transport and reaction Gibbs free energies for reducing overpotential, respectively. A general way of boosting OER kinetics via optimizing the electrode configurations to mitigate reaction overpotential is offered in this study.

20.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(1): 88-91, 2020 Jan 08.
Artículo en Zh | MEDLINE | ID: mdl-32343076

RESUMEN

By analyzing the main problems existing in the current management of medical devices for clinical trials, this study proposes a feasible management model and specific requirements for acceptance, distribution, storage and recovery combining with the characteristics of medical consumable equipment and diagnostic reagent, which provides a favorable guarantee for the authenticity and reliability of clinical trials.


Asunto(s)
Ensayos Clínicos como Asunto , Equipos y Suministros/normas , Indicadores y Reactivos/normas , Proyectos de Investigación/normas , Reproducibilidad de los Resultados
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