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1.
BMC Microbiol ; 17(1): 156, 2017 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-28693413

RESUMEN

BACKGROUND: Bacillus pumilus can secret abundant extracellular enzymes, and may be used as a potential host for the industrial production of enzymes. It is necessary to understand the metabolic processes during cellular growth. Here, an RNA-seq based transcriptome analysis was applied to examine B. pumilus BA06 across various growth stages to reveal metabolic changes under two conditions. RESULTS: Based on the gene expression levels, changes to metabolism pathways that were specific to various growth phases were enriched by KEGG analysis. Upon entry into the transition from the exponential growth phase, striking changes were revealed that included down-regulation of the tricarboxylic acid cycle, oxidative phosphorylation, flagellar assembly, and chemotaxis signaling. In contrast, the expression of stress-responding genes was induced when entering the transition phase, suggesting that the cell may suffer from stress during this growth stage. As expected, up-regulation of sporulation-related genes was continuous during the stationary growth phase, which was consistent with the observed sporulation. However, the expression pattern of the various extracellular proteases was different, suggesting that the regulatory mechanism may be distinct for various proteases. In addition, two protein secretion pathways were enriched with genes responsive to the observed protein secretion in B. pumilus. However, the expression of some genes that encode sporulation-related proteins and extracellular proteases was delayed by the addition of gelatin to the minimal medium. CONCLUSIONS: The transcriptome data depict global alterations in the genome-wide transcriptome across the various growth phases, which will enable an understanding of the physiology and phenotype of B. pumilus through gene expression.


Asunto(s)
Bacillus pumilus/crecimiento & desarrollo , Bacillus pumilus/metabolismo , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Bacillus pumilus/genética , Proteínas Bacterianas/metabolismo , Ciclo del Ácido Cítrico , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Transcriptoma
2.
Mol Genet Genomics ; 291(2): 609-20, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26499957

RESUMEN

Sweet potato [Ipomoea batatas (L.) Lam.], the world's seventh most important food crop, is also a major industrial raw material for starch and ethanol production. In the plant starch biosynthesis pathway, ADP-glucose pyrophosphorylase (AGPase) catalyzes the first, rate-limiting step and plays a pivotal role in regulating this process. In spite of the importance of sweet potato as a starch source, only a few studies have focused on the molecular aspects of starch biosynthesis in sweet potato and almost no intensive research has been carried out on the AGPase gene family in this species. In this study, cDNAs encoding two small subunits (SSs) and four large subunits (LSs) of AGPase isoforms were cloned from sweet potato and the genomic organizations of the corresponding AGPase genes were elucidated. Expression pattern analysis revealed that the two SSs were constitutively expressed, whereas the four LSs displayed differential expression patterns in various tissues and at different developmental stages. Co-expression of SSs with different LSs in Escherichia coli yielded eight heterotetramers showing different catalytic activities. Interactions between different SSs and LSs were confirmed by a yeast two-hybrid experiment. Our findings provide comprehensive information about AGPase gene sequences, structures, expression profiles, and subunit interactions in sweet potato. The results can serve as a foundation for elucidation of molecular mechanisms of starch synthesis in tuberous roots, and should contribute to future regulation of starch biosynthesis to improve sweet potato starch yield.


Asunto(s)
ADN Complementario/genética , Glucosa-1-Fosfato Adenililtransferasa/genética , Ipomoea batatas/genética , Subunidades de Proteína/genética , Clonación Molecular , ADN Complementario/aislamiento & purificación , Regulación de la Expresión Génica de las Plantas , Glucosa-1-Fosfato Adenililtransferasa/aislamiento & purificación , Ipomoea batatas/enzimología , Raíces de Plantas/genética , Subunidades de Proteína/aislamiento & purificación , Homología de Secuencia de Aminoácido , Almidón/biosíntesis , Almidón/genética
3.
Inorg Chem ; 53(1): 21-3, 2014 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-24328282

RESUMEN

Q[8]-based porous materials were synthesized in the presence of [Md-blockCl4](2-) anions as structure inducers. The driving forces of the structure-directing effect of the [Md-blockCl4](2-) anions may be due to the ion-dipole interaction and hydrogen bonding between the [Md-blockCl4](2-) anions and ≡CH or ═CH2 groups on the backs of Q[8] molecules. Moreover, the tests of potential applications show that these porous materials can not only capture organic molecules through the cavity of Q[8] moieties but also adsorb larger organic molecules with different selectivities.

4.
Chem Soc Rev ; 42(24): 9480-508, 2013 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-24048328

RESUMEN

Cucurbit[n]urils are a family of molecular container hosts bearing a rigid hydrophobic cavity and two identical carbonyl fringed portals. They have attracted much attention in supramolecular chemistry because of their superior molecular recognition properties in aqueous media. This review highlights the recent advances and challenges in the field of cucurbit[n]uril-based coordination chemistry. It not only presents progress in the knowledge of such macrocyclic compounds, which range from simple to complicated architectures, but also presents new routes of synthesis and their advantages in hybrid porous solids. The concept of structure "inducer" for their structural design to achieve predictable structures and controlled pores is described. The large pore sizes and hydrophobic cavities of these compounds that lead to unprecedented properties and potential applications are also discussed.

5.
J Cell Biochem ; 114(8): 1720-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23386463

RESUMEN

A range of biological and molecular effects caused by nicotine are considered to effect bone metabolism. Vitamin C functions as a biological antioxidant. This study was to evaluate the in vitro effects of nicotine on human bone marrow stromal cells and whether Vitamin C supplementation show the antagonism action to high concentration nicotine. We used CCK-8, alkaline phosphatase (ALP) activity assay, Von Kossa staining, real-time polymerase chain reaction and Western Blot to evaluate the proliferation and osteogenic differentiation. The results indicated that the proliferation of BMSCs increased at the concentration of 50, 100 ng/ml, got inhibited at 1,000 ng/ml. When Vitamin C was added, the OD for proliferation increased. For ALP staining, we found that BMSCs treated with 50 and 100 ng/ml nicotine showed a higher activity compared with the control, and decreased at the 1,000 ng/ml. Bone morphogenetic protein-2 (BMP-2) expression and the calcium depositions decreased at 100 and 1,000 ng/ml nicotine, while the addition of Vitamin C reversed the down regulation. By real-time PCR, we detected that the mRNA expression of collagen type I (COL-I) and ALP were also increased in 50 and 100 ng/ml nicotine groups (P < 0.05), while reduced at 1,000 ng/ml (P < 0.05). When it came to osteocalcin (OCN), the changes were similar. Taken all together, it is found that nicotine has a two-phase effect on human BMSCs, showing that low level of nicotine could promote the proliferation and osteogenic differentiation while the high level display the opposite effect. Vitamin C could antagonize the inhibitory effect of higher concentration of nicotine partly.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Células de la Médula Ósea/metabolismo , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Estimulantes Ganglionares/farmacología , Nicotina/farmacología , Osteogénesis/efectos de los fármacos , Adulto , Anciano , Ácido Ascórbico/antagonistas & inhibidores , Células de la Médula Ósea/citología , Proteína Morfogenética Ósea 2/biosíntesis , Células Cultivadas , Relación Dosis-Respuesta a Droga , Antagonismo de Drogas , Femenino , Estimulantes Ganglionares/antagonistas & inhibidores , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Nicotina/antagonistas & inhibidores , Células del Estroma/citología , Células del Estroma/metabolismo
6.
J Mater Sci Mater Med ; 24(7): 1781-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23526152

RESUMEN

The aim of this study was to present a non-trypsin 3D cell culture method with a reversible thermosensitive HBCS hydrogel. In this study, hydroxybutyl chitosan (HBCS) was synthesized by grafting hydroxybutyl groups on chitosan molecule chains. The prepared HBCS was water-soluble, and the reversible phase transformation temperature was 26 °C. Scanning electron microscope images illuminated the 3-D network of hydrogel formed irregular porous structure which ranged from 50-250 µm. Cell viability assay indicated that HBCS solution could promote the proliferation of human umbilical vein endothelial cells (HUVECs), and the boost of proliferation was enhanced with the increase of HBCS concentration. HBCS had no harm to the nitric oxide (NO) synthesis functionality of HUVECs. HUVECs could grow and reproduce inside the hydrogel, and showed good vitality after 14-days culture. Meanwhile, cells cultured inside the hydrogel could be passaged successively through the reversible phase transformation process of HBCS. The results revealed that HBCS have the potential to be used for 3-D cell culture without the use of trypsin.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Quitosano/farmacología , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Hidroxibutiratos/farmacología , Técnicas de Cultivo de Célula/instrumentación , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Quitosano/química , Quitosano/farmacocinética , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacocinética , Hidroxibutiratos/química , Transición de Fase , Reología , Temperatura , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
7.
Zhonghua Yi Xue Za Zhi ; 93(11): 816-8, 2013 Mar 19.
Artículo en Zh | MEDLINE | ID: mdl-23859385

RESUMEN

OBJECTIVE: To evaluate the onset of initial pneumatization of paranasal sinuses with magnetic resonance imaging (MRI) and provides references in the diagnosis and treatment of pediatric paranasal sinuses disease. METHODS: The MRI images of paranasal sinuses were retrospectively reviewed for 799 children of 0 month to 15 years old and the first pneumatization time of paranasal sinuses were analyzed. RESULTS: The ethmoidal sinuses was the first pneumatized in 100% (46/46) of newborn children. And 45.7% (21/46) of maxillary sinuses showed pneumatization during the first month of life and 97.8% (45/46) were pneumatized at 7 - 12 months. The pneumatized sphenoid sinuses was first identified as early as 4 months. And 86% (43/50) were pneumatized from 1 to 2 years old. Frontal sinuses was the last pneumatized paranasal sinuses. And 8% (4/50) of frontal sinuses were pneumatized at 1 - 2 years old and 97.8% (42/43) showed pneumatization at 14 - 15 years old. CONCLUSION: MRI may be used to observe the pneumatization of paranasal sinuses. The initial pneumatization time of paranasal sinuses is earlier than previously described.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Senos Paranasales/anatomía & histología , Adolescente , Niño , Preescolar , Femenino , Seno Frontal/anatomía & histología , Humanos , Lactante , Masculino , Estudios Retrospectivos , Seno Esfenoidal/anatomía & histología
8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(12): 995-9, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24524599

RESUMEN

OBJECTIVE: To explore the status of glucometabolic abnormalities in cardiological outpatients without previous diabetes diagnosis and with coronary artery disease (CAD) and hypertension. METHODS: Patients without previous diagnosis of diabetes but with hypertension and CAD aged 18 years or above were recruited from cardiology departments of 11 general hospitals in China. Demographic data, disease diagnosis and medical history were collected. Physical examination and questionnaire survey were performed after the random blood glucose test. Oral glucose tolerance test (OGTT) examination was made for patients with fasting blood glucose ≥ 6.1 mmol/L or postprandial random glucose ≥ 7.8 mmol/L. Adjusted prevalence rates were used in the study. RESULTS: A total of 7778 patients were included in 11 centers. After preliminary screening by fasting blood glucose and random blood glucose tests, 3861 patients were required to take OGTT, and 3019 (78.2%) patients actually took the test. 1287 out of 3019 patients screened with OGTT were diagnosed with diabetes, and the adjusted diabetes prevalence rate was 18.64% (1287/6904). The prevalence rate of diabetes was 19.87% (95/478), 9.22% (352/3819) and 14.81% (153/1033) in patients with CAD, hypertension, and CAD combined with hypertension, respectively. A total of 996 patients were diagnosed with impaired glucose tolerance (IGT) and its prevalence was 14.43% (996/6904). Of the enrolled population, 153 patients with random blood glucose lower than 7.8 mmol/L were also screened with OGTT test, 26.14% (40/153) patients met the diagnostic criteria of diabetes. CONCLUSION: A high prevalence of diabetes is found in patients without previous diagnosis of diabetes and with hypertension and CAD consulting at cardiology departments. We thus suggest to perform OGTT in this patient cohort to improve the early diagnosis of IGT and diabetes, and prevent missed detection of type 2 diabetes mellitus or IGT in cardiovascular patients with normal fasting blood glucose. Our results indicate that it was feasible to use OGTT as a screening tool for detecting diabetes in these patients and the patient compliance is satisfactory.


Asunto(s)
Glucemia/metabolismo , Enfermedad Coronaria/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Hipertensión/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Tamizaje Masivo , Pacientes Ambulatorios
9.
Am J Nucl Med Mol Imaging ; 13(5): 230-244, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023818

RESUMEN

The earlier identification of EGFR mutation status in lung adenocarcinoma patients is crucial for treatment decision-making. Radiomics, which involves high-throughput extraction of imaging features from medical images for quantitative analysis, can quantify tumor heterogeneity and assess tumor biology non-invasively. This field has gained attention from researchers in recent years. The aim of this study is to establish a model based on 18F-FDG PET/CT radiomic features to predict the epidermal growth factor receptor (EGFR) mutation status of lung adenocarcinoma and evaluate its performance. 155 patients with lung adenocarcinoma who underwent 18F-FDG PET/CT scans and EGFR gene detection before treatment were retrospectively analyzed. The LIFEx packages was used to perform 3D volume of interest (VOI) segmentation manually on DICOM images and extract 128 radiomic features. The Wilcoxon rank sum test and least absolute shrinkage and selection operator (LASSO) regression algorithm were applied to filter the radiomic features and establish models. The performance of the models was evaluated by the receiver operating characteristic (ROC) curve and the area under the curve (AUC). Among the models we have built, the radiomic model based on 18F-FDG PET/CT has the best prediction performance for EGFR gene mutation status, with an AUC of 0.90 (95% CI 0.84~0.96) in the training set and 0.79 (95% CI 0.64~0.94) in the test set. In conclusion, we have established a radiomics model based on 18F-FDG PET/CT, which has good predictive performance in identifying EGFR gene mutation status in lung adenocarcinoma patients.

10.
J Mater Sci Mater Med ; 23(2): 375-84, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22139537

RESUMEN

Oleoyl-carboxymethy chitosan (OCMCS) nanoparticles based on chitosan with different molecular weights (50, 170 and 820 kDa) were prepared by self-assembled method. The nanoparticles had spherical shape, positive surface charges and the mean diameters were 157.4, 274.1 and 396.7 nm, respectively. FITC-labeled OCMCS nanoparticles were internalized via the intestinal mucosa and observed in liver, spleen, intestine and heart following oral deliverance to carps (Cyprinus carpio). Extracellular products (ECPs) of Aeromonas hydrophila as microbial antigen was efficiently loaded to form OCMCS-ECPs nanoparticles and shown to be sustained release in PBS. Significantly higher (P < 0.05) antigen-specific antibodies were detected in serum after orally immunized with OCMCS-ECPs nanoparticles than that immunized with ECPs alone and non-immunized in control group in carps. These results implied that amphiphilic modified chitosan nanoparticles had great potential to be applied as carriers for the oral administration of protein drugs.


Asunto(s)
Quitosano/análogos & derivados , Nanopartículas/química , Nanotecnología/métodos , Administración Oral , Aeromonas/metabolismo , Animales , Antiinfecciosos/farmacología , Antígenos/química , Materiales Biocompatibles/química , Carpas , Quitosano/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Luz , Ensayo de Materiales , Microscopía Electrónica de Transmisión/métodos , Peso Molecular , Solubilidad , Estrés Mecánico , Agua/química
11.
Chin J Traumatol ; 14(1): 25-8, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21276364

RESUMEN

OBJECTIVE: To evaluate the preliminary clinical outcomes of coccygectomy in patients with coccydynia after a failure of conservative treatment. METHODS: From May 2002 to January 2010, 31 patients with coccydynia were treated by coccygectomy in our department after conservative measures had failed to produce significant relief. A questionnaire, which included the extent of relief in the painful area, improvement in quality of life, intensity of pain in the sitting position, and pain score during daily activities, was used to evaluate the results. RESULTS: All patients were followed up for 1 to 6 years (mean 3.3 years). The results were excellent in 20 patients (64.5%), good in 7 patients (22.6%), moderate in 3 patients (9.7%) and poor in 1 patient (3.2%). The excellent and good rates amounted to 87.1%. All patients except one had complete resolution of their symptoms and were subjectively highly satisfied with the outcomes of the surgery. Only 2 cases of superficial infection were observed postoperatively. CONCLUSION: Coccygectomy is a feasible management option for patients with coccygodynia that has no response to conservative treatments.


Asunto(s)
Cóccix/cirugía , Dolor de la Región Lumbar/cirugía , Actividades Cotidianas , Adulto , Anciano , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Radiografía
12.
Chin J Traumatol ; 14(1): 53-7, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21276369

RESUMEN

OBJECTIVE: To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. METHODS: This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years). The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. RESULTS: All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood's rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. CONCLUSIONS: The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages.


Asunto(s)
Hilos Ortopédicos , Fijación Interna de Fracturas/métodos , Luxaciones Articulares/cirugía , Articulación Esternoclavicular/lesiones , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Articulación Esternoclavicular/diagnóstico por imagen , Articulación Esternoclavicular/cirugía
13.
Chin J Traumatol ; 14(5): 269-76, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22118480

RESUMEN

OBJECTIVE: Studies showed elastic stable intramedullary nailing (ESIN) of displaced midclavicular fractures has excellent outcomes, as well as high complication rates and specific problems. The aim was to discuss ESIN of midshaft clavicular fractures. METHODS: Totally 60 eligible patients (aged 18-63 years) were randomized to either ESIN group or non-operative group between January 2007 and May 2008. Clavicular shortening was measured after trauma and osseous consolidation. Radiographic union and complications were assessed. Function analysis including Constant shoulder scores and disabilities of the arm, shoulder and hand (DASH) scores were performed after a 15-month follow-up. RESULTS: ESIN led to a signifcantly shorter time to union, especially for simple fractures. In ESIN group, all patients got fracture union, of which 5 cases had medial skin irritation and 1 patient needed revision surgery because of implant failure. In the nonoperative group, there were 3 nonunion cases and 2 symptomatic malunions developed requiring corrective osteotomy. At 15 months after intramedullary stabilization, patients in the ESIN group were more satisfied with the appearance of the shoulder and overall outcome, and they benefited a lot from the great improvement of post-traumatic clavicular shortening. Furthermore, DASH scores were lower and Constant scores were significantly higher in contrast to the non-operative group. CONCLUSION: ESIN is a safe minimally invasive surgical technique with lower complication rate, faster return to daily activities, excellent cosmetic and better functional results, restoration of clavicular length for treating mid-shaft clavicular fractures, resulting in high overall satisfaction, which can be regard as an alternative to plate fixation or nonoperative treatment of mid-shaft clavicular fractures.


Asunto(s)
Fijación Intramedular de Fracturas , Titanio , Adulto , Clavícula , Humanos , Uñas , Resultado del Tratamiento
14.
Chin J Traumatol ; 14(5): 288-92, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22118483

RESUMEN

OBJECTIVE: To evaluate the in vitro and in vivo osteogenic capability of adipose-derived stromal cells (ASCs). METHODS: ASCs were isolated from New Zealand white rabbits and determined by alkaline phosphatase (ALP) staining, von Kossa staining and alizarin red staining. Some specific markers of osteogenic differentiation, including ALP, osteocalcin (OCN), osteopontin (OPN) were examined by reverse transcription-polymerase chain reaction (RT-PCR). In vivo, demineralized bone matrix (DBM)-ASCs composites were implanted into the rabbit calvarial defects created at each side of the longitudinal midline. After 6 weeks, histologic properties of the transplants were analyzed. RESULTS: ASCs were successfully induced into osteogenesis. ALP staining, von Kossa staining and alizarin red staining showed positive results. The expressions of ALP, OCN and OPN were detected in ASCs after cultivation in osteogenic medium. Extensive new bone was observed in the defects transplanted with DBM-ASCs composites. CONCLUSION: ASCs have the potential to differentiate into osteogenic lineage and DBM-ASCs constructs are a promising method for regeneration in bone defects.


Asunto(s)
Tejido Adiposo , Osteogénesis , Animales , Diferenciación Celular , Células Cultivadas , Conejos , Células del Estroma
15.
Water Sci Technol ; 61(9): 2363-74, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20418634

RESUMEN

In this study, a novel chitosan-based polymeric surfactant, H-Oleoyl-Carboxymethyl chitosan was used as a coagulation agent for cleaning residual oil. The characteristics of H-Oleoyl-Carboxymethyl chitosan were investigated by FTIR and XRD. And the adsorption capacities of chitosan and H-O-CMCS for removing the residue oil from the wastewater of oil extraction have been investigated. H-O-CMCS exhibited a greater rate than chitosan in cleaning the residual oil from the wastewater of oil extraction at the optimum conditions. Equilibrium study, Langmuir/Freundlich adsorption models and the pseudo first- and second-order kinetic models were applied to describe the mechanism of adsorption experiments. The experimental data fitted well with the Langmuir model and the second-order kinetic model. Regeneration studies, using by the roasting and rinsing method, were undergone for three successive adsorption/desorption processes. H-O-CMCS still retained the residual oil removal capacity after regeneration.


Asunto(s)
Quitosano/análogos & derivados , Quitosano/química , Petróleo/análisis , Tensoactivos/química , Contaminantes Químicos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Temperatura , Termodinámica
16.
J Mater Sci Mater Med ; 20(8): 1603-10, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19322644

RESUMEN

A novel injectable thermosensitive hydrogel (CS-HTCC/alpha beta-GP) was successfully designed and prepared using chitosan (CS), quaternized chitosan (HTCC) and alpha,beta-glycerophosphate (alpha,beta-GP) without any additional chemical stimulus. The gelation point of CS-HTCC/alpha beta-GP can be set at a temperature close to normal body temperature or other temperature above 25 degrees C. The transition process can be controlled by adjusting the weight ratio of CS to HTCC, or different final concentration of alpha,beta-GP. The optimum formulation is (CS + HTCC) (2% w/v), CS/HTCC (5/1 w/w) and alpha,beta-GP 8.33% or 9.09% (w/v), where the sol-gel transition time was 3 min at 37 degrees C. The drug released over 3 h from the CS-HTCC/alpha,beta-GP thermosensitive hydrogel in artificial saliva pH 6.8. In addition, CS-HTCC/alpha,beta-GP thermosensitive hydrogel exhibited stronger antibacterial activity towards two periodontal pathogens (Porphyromonas gingivalis, P.g and Prevotella intermedia, P.i). CS-HTCC/alpha, beta-GP thermosensitive hydrogel was a considerable candidate as a local drug delivery system for periodontal treatment.


Asunto(s)
Quitosano/química , Quitosano/uso terapéutico , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/uso terapéutico , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Antiinfecciosos/uso terapéutico , Infecciones por Bacteroidaceae/tratamiento farmacológico , Quitosano/administración & dosificación , Quitosano/análogos & derivados , Quitosano/síntesis química , Estabilidad de Medicamentos , Glicerofosfatos/administración & dosificación , Glicerofosfatos/química , Glicerofosfatos/uso terapéutico , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/administración & dosificación , Bombas de Infusión Implantables , Inyecciones Intralesiones , Pruebas de Sensibilidad Microbiana , Enfermedades Periodontales/tratamiento farmacológico , Enfermedades Periodontales/etiología , Enfermedades Periodontales/microbiología , Porphyromonas gingivalis/efectos de los fármacos , Prevotella intermedia/efectos de los fármacos , Espectrofotometría Infrarroja , Temperatura , Termodinámica , Viscosidad
17.
Int J Biol Macromol ; 138: 321-333, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31295499

RESUMEN

The aim of this study was to develop an effective wound dressing using a temperature-responsive hydroxybutyl chitosan (HBC) based hydrogel. The HBC - chitosan (CS) - dopamine (HCS-DOPA) composite hydrogels were prepared by the dopamine self-polymerization at different concentrations (0, 0.5, 1.0 and 2.0 mg/mL), termed as HCS, HCS-DOPA-0.5, HCS-DOPA-1 and HCS-DOPA-2, respectively. The gelling characteristic of HBC hydrogel was not influenced by composite CS and DOPA. The HCS-DOPA composite hydrogels were non-cytotoxic to mouse fibroblast cells (L929), and induced under 5.0% hemolysis rate. In vitro antibacterial studies, composite HCS-DOPA-2 hydrogels exhibited lasting inhibition to S. aureus >8 h. The whole blood test in vitro demonstrated that blood clotting time treated with HCS-DOPA-2 composite hydrogels was shortened to 95.6 s compared with that of HCS in vitro hemostasis. The results suggested that HCS-DOPA-2 composite hydrogels could be applied as a promising wound dressing for hemostasis in vitro.


Asunto(s)
Bivalvos , Quitosano/química , Hemostasis/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Indoles/química , Polímeros/química , Temperatura , Animales , Antibacterianos/química , Antibacterianos/farmacología , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Coagulación Sanguínea/efectos de los fármacos , Fenómenos Químicos , Escherichia coli/efectos de los fármacos , Cinética , Staphylococcus aureus/efectos de los fármacos
19.
Int J Biol Macromol ; 120(Pt A): 152-158, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30092308

RESUMEN

The aim of this study was to develop an effective cell sheet translocation method using a cell adhesive and temperature-responsive hydroxybutyl chitosan hydrogel (HBC). The polydopamine (PD)-coated HBC hydrogels were prepared by the dopamine self-polymerization on the surface of HBC hydrogel with different coating time, termed as P30, P60 and P120, respectively. Gelling property of HBC was not affected by PD coating. The PD-coated HBC hydrogels promoted the attachment and proliferation of mouse fibroblast cells (L929) and human umbilical vein endothelial cells (HUVECs), and allowed formation of monolayer cell sheet. In vitro translocation of HUVECs sheet could be obtained successively through phase transition of PD coated HBC hydrogel from gel to sol, and the cells sheet transferred from P30 hydrogel to a round cell coverglass maintained relatively complete monolayer and normal cell morphology. The results showed that P30 hydrogel has the potential to be used for cell transplantation therapy.


Asunto(s)
Células Inmovilizadas , Quitosano/análogos & derivados , Células Endoteliales de la Vena Umbilical Humana , Hidrogeles/química , Indoles/química , Polímeros/química , Animales , Células Inmovilizadas/metabolismo , Células Inmovilizadas/trasplante , Quitosano/química , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/trasplante , Humanos , Ratones
20.
J Huazhong Univ Sci Technolog Med Sci ; 37(4): 582-586, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28786065

RESUMEN

This study aimed to examine the diagnosis performance of 99mTc-methoxyisobutylisonitrisonitrile (99mTc-MIBI) and multimodality imaging [ultrasound, single-photon emission computed tomography/computed tomography (SPECT/CT)] for hyperparathyroidism (HPT). From Nov. 2009 to Dec. 2015, clinical data of a total of 43 HPT patients (16 males and 27 females; 26-70 years old, average age: 51.60±10.66 years old) were retrospectively analyzed. Among them, 19 patients with primary hyperparathyroidism (PHPT) underwent 99mTc-MIBI planar imaging, 24 [15 with PHPT and 9 with secondary hyperparathyroidism (SHPT)] underwent SPECT/CT hybrid imaging, and 41 (33 with PHPT and 8 with SHPT) had neck ultrasound imaging. Final diagnosis was determined by pathological examination after surgery. The positive rate was compared between different imaging modalities, and the correlation analysis was conducted between imaging results and lesion size or serum parathyroid hormone (PTH) level. The results showed that the total positive rates of 99mTc-MIBI imaging, ultrasound, and the two combined imaging in the 43 HPT cases were 90.70% (39/43), 58.54% (24/41), and 100% (41/41), respectively. According to lesion numbers, the positive rates were 79.10% (53/67), 53.23% (33/62), and 88.71% (55/62), respectively. SPECT/CT hybrid images were positive in all the 24 patients who underwent this examination. The mean maximum diameters of the lesions in 99mTc-MIBI positive and negative patients were 1.96±0.95 cm and 1.36±0.67 cm respectively, with statistically significant difference noted (P=0.03). The T/NT of 99mTc-MIBI imaging at the early phase was correlated positively with serum PTH level (r=0.40, P=0.01). The T/NT of 99mTc-MIBI imaging at both the early phase and the delay phase was correlated positively with lesion size (r=0.51, and r=0.45, respectively; P<0.01 for both). It was concluded that 99mTc-MIBI imaging presents significant value for location diagnosis of HPT, especially when combined with SPECT/CT hybrid imaging or ultrasound. The 99mTc-MIBI uptake correlates positively with serum PTH level and lesion size.


Asunto(s)
Hiperparatiroidismo Primario/diagnóstico por imagen , Imagen Multimodal , Tecnecio Tc 99m Sestamibi/química , Adulto , Anciano , Femenino , Humanos , Hiperparatiroidismo Primario/patología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/metabolismo
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