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1.
Inorg Chem ; 63(20): 9058-9065, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38720438

RESUMEN

Nitrofurans are important synthetic broad-spectrum antibacterial drugs with the basic structure of 5-nitrofuran. Due to their toxicity, it is essential to develop a sensitive sensor with strong anti-interference capabilities for their detection. In this work, two {P4Mo6O31}12--based compounds, [H4(HPTTP)]2{CuI[Mo12O24(OH)6(PO4)3(HPO4)(H2PO4)4]}·xH2O (x = 13 for (1), 7 for (2); HPTTP = 4,4',4″,4‴-(1H-pyrrole-2,3,4,5-tetrayl)tetrapyridine), exhibiting similar coordination but distinct stacking modes. Both compounds were synthesized and used for the electrochemical detection of nitrofuran antibiotics. The tetrapyridine-based ligand was generated in situ during assembly, and its potential mechanism was discussed. Composite electrode materials, formed by mixing graphite powder with compounds 1-2 and physically grinding them, proved to be highly effective in the electrochemical trace detection of furazolidone (FZD) and furaltadone hydrochloride (FTD·HCl) under optimal conditions. Besides, the possible electrochemical detection mechanisms of two nitro-antibiotics were studied.


Asunto(s)
Antibacterianos , Complejos de Coordinación , Cobre , Nitrofuranos , Polímeros , Antibacterianos/química , Antibacterianos/análisis , Ligandos , Nitrofuranos/análisis , Nitrofuranos/química , Cobre/química , Cobre/análisis , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Polímeros/química , Molibdeno/química , Piridinas/química , Estructura Molecular , Técnicas Electroquímicas , Modelos Moleculares
2.
Environ Sci Technol ; 58(9): 4060-4069, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38331396

RESUMEN

Microplastic pollution, an emerging pollution issue, has become a significant environmental concern globally due to its ubiquitous, persistent, complex, toxic, and ever-increasing nature. As a multifaceted and diverse suite of small plastic particles with different physicochemical properties and associated matters such as absorbed chemicals and microbes, future research on microplastics will need to comprehensively consider their multidimensional attributes. Here, we introduce a novel, conceptual framework of the "microplastome", defined as the entirety of various plastic particles (<5 mm), and their associated matters such as chemicals and microbes, found within a sample and its overall environmental and toxicological impacts. As a novel concept, this paper aims to emphasize and call for a collective quantification and characterization of microplastics and for a more holistic understanding regarding the differences, connections, and effects of microplastics in different biotic and abiotic ecosystem compartments. Deriving from this lens, we present our insights and prospective trajectories for characterization, risk assessment, and source apportionment of microplastics. We hope this new paradigm can guide and propel microplastic research toward a more holistic era and contribute to an informed strategy for combating this globally important environmental pollution issue.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos/toxicidad , Ecosistema , Estudios Prospectivos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad
3.
Langmuir ; 39(15): 5239-5249, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37014629

RESUMEN

The technology based on immobilized enzymes was employed to screen the constituents inhibiting disease-related enzyme activity from traditional Chinese medicine, which is expected to become an important approach of innovative drug development. Herein, the Fe3O4@POP composite with a core-shell structure was constructed for the first time with Fe3O4 magnetic nanoparticles as the core, 1,3,5-tris (4-aminophenyl) benzene (TAPB) and 2,5-divinylterephthalaldehyde (DVA) as organic monomers, and used as the support for immobilizing α-glucosidase. Fe3O4@POP was characterized by transmission electron microscopy, energy-dispersive spectrometry, Fourier transform infrared, powder X-ray diffraction, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. Fe3O4@POP exhibited a distinct core-shell structure and excellent magnetic response (45.2 emu g-1). α-Glucosidase was covalently immobilized on core-shell Fe3O4@POP magnetic nanoparticles using glutaraldehyde as the cross-linking agent. The immobilized α-glucosidase possessed improved pH stability and thermal stability as well as good storage stability and reusability. More importantly, the immobilized enzyme exhibited a lower Km value and enhanced affinity for the substrate than the free one. The immobilized α-glucosidase was subsequently used for inhibitor screening from 18 traditional Chinese medicines in combination with capillary electrophoresis analysis among which Rhodiola rosea exhibited the highest enzyme inhibitory activity. These positive results demonstrated that such magnetic POP-based core-shell nanoparticles were a promising carrier for enzyme immobilization and the screening strategy based on immobilized enzyme provided an effective way to rapidly explore the targeted active compounds from medicinal plants.


Asunto(s)
Enzimas Inmovilizadas , Nanopartículas de Magnetita , Enzimas Inmovilizadas/química , alfa-Glucosidasas/química , alfa-Glucosidasas/metabolismo , Polímeros , Porosidad , Cinética , Fenómenos Magnéticos , Nanopartículas de Magnetita/química , Concentración de Iones de Hidrógeno , Estabilidad de Enzimas , Temperatura
4.
Mediators Inflamm ; 2022: 2083057, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466157

RESUMEN

Objective: The concentration of exhaled NO and CO is considered as a candidate marker of respiratory inflammatory disease. This report discusses the exhaled NO and CO in the auxiliary diagnosis and evaluation of allergic rhinitis (AR). Methods: 60 AR patients from October 2017 to March 2019, compared with 30 healthy controls. The severity of AR disease was distinguished by symptom score. Both groups were tested for exhaled nitric oxide through the nose or mouth and exhale carbon monoxide through the mouth. AR patients received glucocorticoid nasal spray for 1 month and were tested again for nNO, eNO, eCO, and symptom score. Results: Before treatment, all the nNO, eNO, and eCO of the AR group were higher than the control group. There were differences in the severe and moderate subgroup: severe > moderate > mild. eCO was not significantly different between the mild and control groups. The nNO, eNO, and eCO levels were positively correlated with symptom score. After treatment, nNO decreased significantly in the three subgroups; eNO and eCO in the severe AR group decreased significantly. Drawing the ROC curve, the area under curve (AUC) of nNO is 0.978. The AUC of eNO and eCO was 0.786 and 0.577, respectively. Conclusion: The nNO, eNO, and eCO in the AR group are higher than healthy people, which positively correlated with the severity of AR symptoms. The detection of nNO, eNO, and eCO can monitor the changes of AR. The detection of nNO level as an indicator of AR auxiliary diagnosis has high accuracy.


Asunto(s)
Monóxido de Carbono , Rinitis Alérgica , Humanos , Óxido Nítrico , Espiración , Rinitis Alérgica/diagnóstico , Área Bajo la Curva
5.
Dent Traumatol ; 38(1): 62-70, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34275178

RESUMEN

BACKGROUND/AIMS: Under-estimating the damage caused by trauma to the dental structures may delay treatment. Timely and accurate diagnosis remains challenging in clinical practice. Radiography is an important modality for the diagnosis of traumatic injuries. The aim of this study was to compare the efficacy of periapical radiography and cone beam computed tomography for the diagnosis of trauma to the anterior maxillary dentoalveolar region in children and adolescents. MATERIAL AND METHODS: Images of patients who underwent both periapical radiography and cone beam computed tomography simultaneously because of trauma to the anterior maxillary region between January 2016 and January 2020 were analyzed retrospectively. Pairwise comparison between the receiver operating characteristic curves was performed to statistically compare the two methods for the diagnosis of crown fractures, root fractures, alveolar bone fractures and luxations, tooth resorption, and periapical radiolucencies. RESULTS: A total of 190 patients met the inclusion criteria. There were 120 (63.2%) males and 70 (36.8%) females, with a mean age of 11.1 years (range: 6-17 years). A crown fracture was observed in 144 teeth, while a root fracture was observed in 71 teeth. Alveolar fracture and luxation were observed in 44 incisors. During follow-up, tooth resorption and periapical radiolucencies were observed in 25 and 33 teeth, respectively. Pairwise receiver operating characteristic curve analysis revealed that cone beam computed tomography was significantly superior to periapical radiography for the diagnosis of root fractures, alveolar fractures and luxations, and tooth resorption (p < .05). However, no significant differences were found for the diagnosis of crown fractures and periapical radiolucencies (p > .05). CONCLUSIONS: Cone beam computed tomography in the low-dose mode was better for diagnosing root and bone fractures and resorption, but no different to periapical radiographs for crown fractures and periapical radiolucencies in pediatric patients.


Asunto(s)
Radiografía Dental Digital , Fracturas de los Dientes , Adolescente , Niño , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Incisivo , Masculino , Estudios Retrospectivos , Raíz del Diente
6.
Electrophoresis ; 42(20): 2081-2086, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34347304

RESUMEN

An online method based on CE was established to screen α-glucosidase inhibitors from traditional Tibetan medicine extracts. First, the inner wall at the inlet of capillary column was simply and effectively functionalized by dopamine-polyethyleneimine co-deposition method, which combines the adhesion property of dopamine and easy cationization of polyethyleneimine. Then α-glucosidase was rapidly immobilized on the inner wall of the capillary column by electrostatic adsorption. The inter- and intraday repeatability of the peak area of the enzymatic reaction product (p-nitrophenol) in a capillary was evaluated, and RSD% (n = 3) was 0.94% and 1.09%, respectively. Good batch-to-batch reproducibility of the peak area between different capillaries (RSD = 2.1%, n = 5) shows that the preparation method has good reproducibility. The Michaelis-Menten constant of the immobilized α-glucosidase was measured to be 1.18 mM, and the capillary column enzyme reactor retained 85.9% of initial activity after 30 cycles. Finally, it was applied to the screening of enzyme inhibitors in 20 traditional Tibetan medicine extracts. Sixteen medicines with inhibitory activity were screened out, and Rheum australe had the strongest inhibitory effect with an inhibitory rate of 83.3 ± 0.4%. These results showed that this method is effective to find potential enzyme inhibitors.


Asunto(s)
Dopamina , Enzimas Inmovilizadas , Inhibidores de Glicósido Hidrolasas , Polietileneimina , alfa-Glucosidasas , Capilares , Evaluación Preclínica de Medicamentos , Inhibidores de Glicósido Hidrolasas/farmacología , Extractos Vegetales , Reproducibilidad de los Resultados
7.
Anal Biochem ; 605: 113832, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32717184

RESUMEN

Immobilized enzyme has been gradually applied to the screening of enzyme inhibitors owing to its retained catalytic activity and reusability. In this work, the cheap and available cellulose filter paper (CFP) was used as a carrier for the immobilization of α-glucosidase (α-Glu). In virtue of the self-polymerization-adhesion behavior of dopamine, CFP was coated with a polydopamine composite layer and then α-glucosidase is covalently bound to the modified CFP through Schiff base reaction and Michael addition reaction. Combined with capillary electrophoresis (CE) analysis, enzyme reaction kinetics, inhibition kinetics and other performance of the prepared immobilized enzyme (CFP/Dopa/α-Glu) were examined and verified. Its Michaelis constant (Km) was calculated to be 0.83 mM. And the inhibition constant (Ki) and half-maximal inhibitory concentration (IC50) for acarbose were determined to be 0.16 and 0.17 µM, respectively. CFP/Dopa/α-Glu had the same optimum working pH value (7.0) as free α-Glu and slightly higher working temperature (65 °C) than free α-Glu. In addition, it exhibited good batch-to-batch reproducibility with an RSD value of 4.4% (n = 10), and excellent reusability with 71% of the initial enzyme activity after being recycled 11 times. Finally, the CFP/Dopa/α-Glu was applied to screen α-glucosidase inhibitors from 11 traditional Chinese medicines, and Terminalia chebula possessed the strongest inhibition effect on α-glucosidase.


Asunto(s)
Medicamentos Herbarios Chinos/química , Inhibidores de Glicósido Hidrolasas/análisis , alfa-Glucosidasas/química , Inhibidores Enzimáticos/análisis , Enzimas Inmovilizadas/química , Indoles/química , Cinética , Polímeros/química , Terminalia/química
8.
Oral Dis ; 26(5): 998-1009, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32144839

RESUMEN

OBJECTIVES: We aimed to investigate whether skeletal-specific H-type blood vessels exist in alveolar bone and how they function in alveolar bone remodeling. MATERIALS AND METHODS: H-type vessels with high expression of CD31 and Endomucin (CD31hi Emcnhi ) were immunostained in alveolar bone. Abundance and age-related changes in CD31hi Emcnhi endothelial cells (H-ECs) were detected by flow cytometry. Osteoprogenitors association with H-type vessels and bone mass were detected in tooth extraction model of alveolar bone remodeling by immunohistofluorescence and micro-CT, respectively. Transcription and expression of H-EC feature genes during in vitro Notch inhibition were measured by RT-qPCR and immunocytofluorescence. RESULTS: We verified that H-type vessels existed in alveolar bone, the abundance of which was highest at infancy age, then decreased but maintained a constant level during aging. In tooth extraction model, H-ECs significantly increased with concomitant perivascular accumulation of Runx2+ osteoprogenitors and gradually augmentation of bone mass. Notch inhibition of in vitro cultured H-ECs resulted in decreased expression levels of Emcn and hes1, but not Pecam1 or Kdr genes, with decreased expression levels of H-EC numbers, accordingly. CONCLUSIONS: The present study suggests that H-type vessels promote osteogenesis during alveolar bone remodeling. Notch signaling pathway regulates expression of Emcn and possibly determines fate and functions of alveolar H-ECs.


Asunto(s)
Remodelación Ósea , Células Endoteliales , Osteogénesis , Extracción Dental , Animales , Ratones , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/genética
9.
Zhongguo Zhong Yao Za Zhi ; 43(1): 79-85, 2018 Jan.
Artículo en Zh | MEDLINE | ID: mdl-29552815

RESUMEN

This study aimed to prepare andrographolide (AP)-loaded glycyrrhizic acid (GA) micelles (AP-GA)-PMs to enhance the solubility and anti-tumor effect of andrographolide. Firstly, andrographolide (AP) was used as the model drug and glycyrrhizic acid (GA) as carriers to prepare (AP-GA)-PMs. Then the preparation methods and the ratios of drug and carrier were screened and optimized based on particle size, encapsulation efficiency (EE) and loading capacity of micelles. Finally, the pharmaceutical characters and the inhibition rate on HepG2 cells were evaluated on the (AP-GA)-PMs prepared by optimal process. The results showed that the prepared micelles under the optimal process had a nanosize of (127.11±1.38) nm, zeta potential of (-24.01±0.55) mV, the entrapment efficiency rate of (92.01±4.02)% , the drug loading rate of (51.44±1.24)% and high storage stability at 4 °C in 30 d, with slow but highly stable in vitro release. Moreover, (AP-GA)-PMs with the IC50 value of 19.25 mg·L⁻¹ had a more synergistic and better anti-tumor effect in comparison with AP (IC50=122.40 mg·L⁻¹) on HepG2 cells (P<0.01). In conclusion, the (AP-GA)-PMs prepared with glycyrrhizic acid as a carrier had a small particle size, large drug loading capacity, and high stability, and could significantly improve the anti-tumor effects of AP.


Asunto(s)
Antineoplásicos/farmacología , Diterpenos/farmacología , Portadores de Fármacos/química , Ácido Glicirrínico/química , Micelas , Tamaño de la Partícula , Polímeros
10.
Zhongguo Zhong Yao Za Zhi ; 40(21): 4182-8, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-27071253

RESUMEN

With polyethylene glycol vitamin E succinate (TPGS) as the carrier materials, and berberine hydrochloride ( BER) as model drug, we formed berberine hydrochloride (BER) -loaded TPGS nanomicells (BER-PMs) using filming-rehydration method to improve its solubility and in vitro anti-tumor effect. The transmission electron microscope (TEM) was used to observe the particle appearance; particle detector was used to detect the diameter and Zeta potential; and ultracentrifugation was utilized to determine the encapsulation efficiency (EE) and drug-loading (DD); dynamic dialysis method was used to study the in vitro release behavior of BER-PMs, and the anti-tumor activity against MCF-7 cells was determined by MTT method. Results showed that the average particle size of BER-PMs was (12.45 ± 1.46) nm; particle size was uniform and spherical; drug loading and encapsulation efficiency were (5.7 ± 0.22)% and (95.67 ± 5.35)%, respectively. Zeta potential was (-1.12 ± 0.23) mV; release rate within 24 h was 37.20% and 41.14% respectively in pH 7.4 and pH 6.5 phosphate buffer in vitro; compared with BER, BER-PMs can significantly inhibit MCF-7 cell proliferation (P < 0.05), promote cell apoptosis and improve the anti-tumor activity of BER in vitro. Therefore, the formed berberine hydrochloride micelle can more effectively promote the apoptosis of MCF-7 cell, and improve the drug's in vitro anti-tumor effect.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Berberina/química , Berberina/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Células MCF-7 , Tamaño de la Partícula , Polímeros/química , Polímeros/farmacología , Solubilidad
11.
Pharm Biol ; 52(9): 1179-88, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24646303

RESUMEN

CONTEXT: c-Myc plays a key role in glioma cancer stem cell maintenance. A drug delivery system, nanoparticles loading plasmid DNAs inserted with siRNA fragments targeting c-Myc gene (NPs-c-Myc-siRNA-pDNAs), for the treatment of glioma, has not previously been reported. OBJECTIVE: NPs-c-Myc-siRNA-pDNAs were prepared and evaluated in vitro. MATERIALS AND METHODS: Three kinds of c-Myc-siRNA fragments were separately synthesized and linked with empty siRNA expression vectors in the mole ratio of 3:1 by T4 DNA ligase. The linked products were then separately transfected into Escherichia coli. DH5α followed by extraction with Endofree plasmid Mega kit (Qiagen, Hilden, Germany) obtained c-Myc-siRNA-pDNAs. Finally, the recombinant c-Myc-siRNA3-pDNAs, generating the highest transfection efficiency and the greatest apoptotic ability, were chosen for encapsulation into NPs by the double-emulsion solvent-evaporation procedure, followed by stability, transfection efficiency, as well as qualitative and quantitative apoptosis evaluation. RESULTS: NPs-c-Myc-siRNA3-pDNAs were obtained with spherical shape in uniform size below 150 nm, with the zeta potential about -18 mV, the encapsulation efficiency and loading capacity as 76.3 ± 5.4% and 1.91 ± 0.06%, respectively. The stability results showed that c-Myc-siRNA3-pDNAs remained structurally and functionally stable after encapsulated into NPs, and NPs could prevent the loaded c-Myc-siRNA3-pDNAs from DNase degradation. The transfection efficiency of NPs-c-Myc-siRNA3-pDNAs was proven to be positive. Furthermore, NPs-c-Myc-siRNA3-pDNAs produced significant apoptosis with the apoptotic rate at 24.77 ± 5.39% and early apoptosis cells observed. DISCUSSION AND CONCLUSION: Methoxy-poly-(ethylene-glycol)-poly-(lactide-co-glycolide) nanoparticles (MPEG-PLGA-NPs) are potential delivery carriers for c-Myc-siRNA3-pDNAs.


Asunto(s)
Genes myc/genética , Glioma/genética , Nanopartículas , ARN Interferente Pequeño/administración & dosificación , Animales , Apoptosis/genética , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Escherichia coli/genética , Glioma/terapia , Tamaño de la Partícula , Plásmidos , Poliésteres/química , Polietilenglicoles/química , Ratas , Transfección
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(5): 619-21, 2013 Oct.
Artículo en Zh | MEDLINE | ID: mdl-24078585

RESUMEN

OBJECTIVE: To extracted DNA from ancient human teeth dated 3000 years ago unearthed in Xi'an and determine the genders for the individuals. METHODS: Thirty five ancient human teeth were studied. A 'Reverse-root-canal' technique and a Chelex-100 solution were used to extract the DNA. Specific primers for Amelogenin gene were designed for PCR amplification. RESULTS: Genomic DNA was successfully extracted from 30 samples, for which 8 were determined to be males and 22 were females. CONCLUSION: The 'Reverse-root-canal' technique may be used for extracting DNA from ancient human teeth. Genetics method can supplement physical anthropology for determination of sex for ancient samples.


Asunto(s)
ADN/genética , Análisis para Determinación del Sexo , Diente/química , Amelogenina/genética , China , ADN/análisis , ADN/aislamiento & purificación , Femenino , Historia Antigua , Humanos , Masculino , Paleodontología , Reacción en Cadena de la Polimerasa
13.
Zhongguo Zhong Yao Za Zhi ; 38(7): 995-9, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23847944

RESUMEN

OBJECTIVE: To optimize the conditions of purifying the total alkaloids in Aconitum szechenyianum with macroporous adsorption resin, and compare the content of total alkaloids and aconitine in A. szechenyianum from different producing areas, in order to provide basis for further studies. METHOD: The orthogonal experiment method was adopted for optimizing the conditions of purifying the total alkaloids in A. szechenyianum with macroporous adsorption resin. The content of total alkaloids and aconitine were determined by using the titration method. The total alkaloids in A. szechenyianum from different producing areas were purified under optimum processing conditions. Aconitine was determined by HPLC. RESULT: Different processing conditions showed different influences on the purification of total alkaloids. The optimum conditions were resin type HPD-722, ethanol concentration of 80% , and ethanol elution volume of 80 mL x min(-1). The contents of aconitine in A. szechenyianum from different producing areas--Qinghai, Maxianshan, Ningxia and Yongdeng were 0.493 5, 0.883 5, 1.527 8, 1.664 4 mg x g(-1), respectively. CONCLUSION: The optimum processing conditions used in this essay could be used for purifying the total alkaloids and aconitine. A. szechenyianum from Yongdeng and Gansu contains the highest content of aconitine.


Asunto(s)
Aconitina/química , Aconitum/química , Alcaloides/química , Medicamentos Herbarios Chinos/química , Aconitina/aislamiento & purificación , Adsorción , Alcaloides/aislamiento & purificación , China , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/aislamiento & purificación , Porosidad , Resinas Sintéticas/química
14.
Environ Sci Pollut Res Int ; 30(13): 37118-37126, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36571680

RESUMEN

Yellow mealworm (Tenebrio molitor L.) larvae can depolymerize and degrade polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC). In this study, mealworms were utilized to biodegrade PE, PS, and PVC. Additionally, the effects of plastic degradation on the growth and development of yellow mealworm larvae were investigated by investigating the physiological indices and nutritional components of the larvae after plastic degradation. The results showed that degradation of plastics (PS, PE, and PVC) was promoted at a feeding amount of 0.50 g. However, the degradation of PVC at this concentration increased the mortality of yellow mealworms. In contrast, the degradation of a small amount of PS (0.10 g) promoted the nutritional value of crude protein (45.7 ± 2.08%) and phosphorus (1.23 ± 0.04%), had a lower larval mortality rate (7.90 ± 1.10%), and thus did not have a significant effect on the growth and development of yellow mealworms.


Asunto(s)
Poliestirenos , Tenebrio , Animales , Poliestirenos/metabolismo , Tenebrio/metabolismo , Polietileno/metabolismo , Larva/metabolismo , Cloruro de Polivinilo/metabolismo , Plásticos/metabolismo
15.
Comput Math Methods Med ; 2022: 1644734, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35872961

RESUMEN

Purpose: The purpose of this study is to survey the prevalence and morphology of the maxillary sinus septum, which might increase the rate of maxillary sinus membrane perforation during maxillary sinus floor elevation surgery, among northern Chinese, and to further analyze the relationship between gender, age, edentulous type, and prevalence of maxillary sinus septa. Methods: The cross-sectional retrospective study was based on an analysis of Cone Beam Computed Tomography (CBCT) images of maxillary sinus which had been obtained from patients who visited radiology department of Beijing Stomatology Hospital of Capital Medical University (Beijing, China) during the period from January 2019 to December 2019. The data of demographic characteristic, prevalence, position, direction, and morphology of maxillary sinus septum were collected and further analyzed by SPSS version 25.0.1 and R version 3.5.1 software program. Results: 595 patients were included in this study, and 1190 maxillary sinuses were analyzed and the incidence rate of the sinus septum was 46.9%. 399 (33.5%) sinuses had one or more septa in 279 (46.9%) patients. In addition, maxillary sinus septa incidence showed no significant differences among gender, age, and edentulous type. The segment second molar had the highest incidence rate of septa. Conclusion: In this study, a higher incidence of the maxillary sinus septum was found in the northern Chinese, and its distribution varied with its position, morphology, and direction.


Asunto(s)
Elevación del Piso del Seno Maxilar , Enfermedades de la Lengua , China/epidemiología , Tomografía Computarizada de Haz Cónico , Estudios Transversales , Humanos , Seno Maxilar/anatomía & histología , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Prevalencia , Estudios Retrospectivos
16.
Mol Cell Biol ; 42(7): e0055921, 2022 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-35708320

RESUMEN

Charcot-Marie-Tooth type 4D (CMT4D) is an autosomal recessive demyelinating form of CMT characterized by progressive motor and sensory neuropathy. N-myc downstream regulated gene 1 (NDRG1) is the causative gene for CMT4D. Although more CMT4D cases have been reported, the comprehensive molecular mechanism underlying CMT4D remains elusive. Here, we generated a novel knockout mouse model in which the fourth and fifth exons of the Ndrg1 gene were removed. Ndrg1-deficient mice develop early progressive demyelinating neuropathy and limb muscle weakness. The expression pattern of myelination-related transcriptional factors, including SOX10, OCT6, and EGR2, was abnormal in Ndrg1-deficient mice. We further investigated the activation of the ErbB2/3 receptor tyrosine kinases in Ndrg1-deficient sciatic nerves, as these proteins play essential roles in Schwann cell myelination. In the absence of NDRG1, although the total ErbB2/3 receptors expressed by Schwann cells were significantly increased, levels of the phosphorylated forms of ErbB2/3 and their downstream signaling cascades were decreased. This change was not associated with the level of the neuregulin 1 ligand, which was increased in Ndrg1-deficient mice. In addition, the integrin ß4 receptor, which interacts with ErbB2/3 and positively regulates neuregulin 1/ErbB signaling, was significantly reduced in the Ndrg1-deficient nerve. In conclusion, our data suggest that the demyelinating phenotype of CMT4D disease is at least in part a consequence of molecular defects in neuregulin 1/ErbB signaling.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Enfermedad de Refsum , Animales , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/metabolismo , Receptores ErbB , Ratones , Neurregulina-1/genética , Neurregulina-1/metabolismo , Fenotipo , Enfermedad de Refsum/genética , Enfermedad de Refsum/metabolismo , Células de Schwann/metabolismo
18.
Naturwissenschaften ; 98(5): 435-41, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21484260

RESUMEN

Captorhinids, a clade of Paleozoic reptiles, are represented by a rich fossil record that extends from the Late Carboniferous into the Late Permian. Representatives of this clade dispersed from the equatorial regions of Laurasia into the temperate regions of Pangea during the Middle and Late Permian. This rich fossil record shows that there was an evolutionary trend from faunivorous to omnivorous and herbivorous feeding habits within this clade. The discovery of well-preserved captorhinid materials in the Middle Permian of China allows us to determine that the new taxon, Gansurhinus qingtoushanensis, gen. et sp. nov, is a member of Moradisaurinae, a clade of captorhinids with multiple tooth rows arranged in parallel. The presence of this moradisaurine in the Middle Permian of south central Asia leads us to suggest that paleogeographic changes during the Permian, with part of what is today China becoming a large peninsula of Pangea, allowed these early reptiles as well as other terrestrial vertebrates to extend their geographic ranges to this region of the Late Paleozoic supercontinent.


Asunto(s)
Fósiles , Reptiles/anatomía & histología , Reptiles/clasificación , Animales , Huesos/anatomía & histología , China , Paleontología , Filogenia , Especificidad de la Especie
19.
Ann Palliat Med ; 10(7): 8431-8436, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33977729

RESUMEN

Necrotizing fasciitis (NF) is a rare, fulminant, lethal soft-tissue infection result in fascial necrosis, it is rarer in the head and neck area. Infection caused by Klebsiella oxytoca is much less common. Therefore, we reported a case of NF in the maxillofacial region, neck and upper mediastinum caused by Klebsiella oxytoca as the main cause recently treated in our department. The patient is a middle-aged male with a 10-year history of diabetes with unstable insulin control. The main symptoms were pain on left side with dysphagia and fever and the situation was getting worse. The patient had limited ability to have mouth open and had hyperemia, swelling on the left pharynx, maxillofacial area, and upper left neck and skin tenderness, and all symptoms were getting worse quick. The CT mainly found out that left oropharyngeal wall, parotid gland area, bilateral submaxilla, left neck, and superior mediastinum are swelling with gas. The blood test result: leukocytes count 16.64×109/L, neutrophils percentage 85.8%; C-Pr 320 mg/L; urinary routine: urine glucose (+++++), ketone bodies (+++++); fasting glucose metabolism: glucose 21.33 mmol/L, glycosylated albumin 47.67%. Three incisions of facial and neck were performed to drain pus. Result of bacteria culture: Klebsiella oxytoca and Streptococcus constellatus During treatment of DKA and reduce patient glucose level, we also treated patient with neck and trachea incisions to drain pus and cleaned daily wound area and used different antibiotics according to the bacteria culture and CT results. And finally, the patient was cured and discharged from hospital. This case of NF was very rare not only the bacteria in this case but also the pathological changes related (involving the mediastinum). The report of his diagnosis and treatment can provide experience for future treatments.


Asunto(s)
Fascitis Necrotizante , Streptococcus constellatus , Humanos , Klebsiella oxytoca , Masculino , Mediastino , Persona de Mediana Edad , Cuello
20.
Artículo en Inglés | MEDLINE | ID: mdl-33621797

RESUMEN

In this work, cellulose filter paper (CFP), which is inexpensive and commercially available, was used as the carrier, and the immobilized α-glucosidase was obtained by two steps: firstly, the surface of CFP was modified by polydopamine/polyethyleneimine (PDA/PEI) co-deposition method to obtain CFP-PDA/PEI with a uniform coating of rich positive charge; subsequently, α-glucosidase was immobilized on the CFP-PDA/PEI by electrostatic adsorption. The free enzyme and immobilized enzyme have the same optimal temperature (70℃) and pH (8.0), and their Km is similar, which is 2.2 and 2.8, respectively. These results show that the immobilization process does not change the properties of the enzyme greatly. The immobilized enzyme still maintains 75.6% of its initial activity after 10 repeated uses, showing good reusability. The excellent repeatability (RSD = 2.2%, n = 5) and the verification of competitive inhibitor (acarbose) illustrates the reliability of the immobilized enzymes for enzyme inhibitor screening. Finally, combined with CE, a screening method based immobilized α-glucosidase was proposed and applied to screen the α-glucosidase inhibitory from 10 kinds of Traditional Chinese medicines (TCMs) in vitro. The results indicated that the method was a very effective tool for screening potential α-glucosidase inhibitors from TCMs.


Asunto(s)
Celulosa/análogos & derivados , Dopamina/química , Enzimas Inmovilizadas/metabolismo , Inhibidores de Glicósido Hidrolasas , Polietileneimina/análogos & derivados , alfa-Glucosidasas/metabolismo , Celulosa/química , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/metabolismo , Electroforesis Capilar , Enzimas Inmovilizadas/química , Inhibidores de Glicósido Hidrolasas/análisis , Inhibidores de Glicósido Hidrolasas/metabolismo , Concentración de Iones de Hidrógeno , Papel , Polietileneimina/química , Temperatura , alfa-Glucosidasas/química
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