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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(7): 708-715, 2024 Jul 15.
Artículo en Zh | MEDLINE | ID: mdl-39014947

RESUMEN

OBJECTIVES: To investigate the expression of CD123 in children with acute lymphoblastic leukemia (ALL) and its effect on the clinical characteristics and prognosis of children with B-lineage acute lymphoblastic leukemia (B-ALL). METHODS: A retrospective analysis was conducted on the clinical data of 251 children with ALL who were admitted to the Department of Hematology and Oncology, Children's Hospital of Kunming Medical University, from December 2019 to June 2022. According to the expression of CD123 at initial diagnosis, the children were divided into CD123+ group and CD123- group, and the two groups were compared in terms of clinical characteristics and treatment outcome. The factors influencing the prognosis were analyzed. RESULTS: Among the 251 children with ALL, there were 146 children (58.2%) in the CD123+ group. The B-ALL group had a significantly higher positive expression rate of CD123 than the acute T lymphocyte leukemia group (P<0.05). Compared with the CD123- group, the CD123+ group had significantly lower peripheral blood leukocyte count and percentage of juvenile cells and a significantly higher proportion of children with high hyperdiploid karyotype or an age of 1-10 years, with a relatively low proportion of children with E2A-PBX1 fusion gene (P<0.05). The multivariate Cox proportional-hazards regression model analysis showed that compared with the >10 years group, the 1-10 years group had a significantly higher overall survival rate (P<0.05), and compared with the high risk group, the moderate risk group had a significantly higher event-free survival rate in children with B-ALL (P<0.05). CONCLUSIONS: CD123 is widely expressed in children with B-ALL, and positive expression of CD123 might be an indicator for good prognosis in children with B-ALL, which is of great significance for evaluating the efficacy of remission induction therapy and survival prognosis of children with B-ALL.


Asunto(s)
Subunidad alfa del Receptor de Interleucina-3 , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Masculino , Femenino , Niño , Preescolar , Subunidad alfa del Receptor de Interleucina-3/análisis , Subunidad alfa del Receptor de Interleucina-3/genética , Pronóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Estudios Retrospectivos , Lactante , Adolescente
2.
Cancer ; 129(13): 2013-2022, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36951498

RESUMEN

BACKGROUND: Minimal residual disease (MRD) is an important prognostic factor for survival in adults with acute leukemia. The role of pretransplantation MRD status in myelodysplastic syndrome with excess blasts (MDS-EB) is unknown. This study retrospectively analyzed the relationship between pretransplantation MRD status and long-term survival. MATERIALS AND METHODS: Patients with MDS-EB who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) from March 5, 2005, to November 8, 2020, were included. The relationship between pretransplantation MRD status and long-term survival was analyzed using univariate and multivariate logistic regression models. RESULTS: Of 220 patients with MDS-EB who underwent allo-HSCT, 198 were eligible for inclusion in this multicenter, retrospective cohort study. Complete remission was attained in 121 (61.1%) patients, and 103 patients underwent detection of MRD pretransplantation, with 67 patients being MRD-positive and 36 patients being MRD-negative. The median follow-up time was 16 months, the median age was 41 years (6-65 years), and 58% of the patients were men. The 3-year disease-free survival (DFS) and overall survival (OS) probabilities for all patients were 70.1% and 72.9%, respectively. For patients in complete remission, the 3-year DFS and OS probabilities were 72.2% and 74.8%, respectively. Further analysis found that the 3-year DFS rates of MRD-negative and MRD-positive patients were 85.6% and 66.5% (p = .045), respectively, whereas the 3-year OS rates were 91.3% and 66.4% (p = .035), respectively. Univariate and multivariate analyses showed that poor pretransplantation MRD clearance was an independent prognostic risk factor for DFS and OS. CONCLUSION: Poor pretransplantation MRD clearance is an independent prognostic risk factor for long-term survival after allo-HSCT for patients with MDS-EB. PLAIN LANGUAGE SUMMARY: Poor minimal residual disease clearance pretransplanation is an independent prognostic risk factor for long-term survival after allogeneic hematopoietic stem cell transplantation for patients with myelodysplastic syndrome with excess blasts.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Adulto , Masculino , Humanos , Femenino , Pronóstico , Estudios Retrospectivos , Neoplasia Residual/diagnóstico , Síndromes Mielodisplásicos/terapia , Factores de Riesgo
3.
Sensors (Basel) ; 22(5)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35271049

RESUMEN

High-precision, real-time, and long-range target geo-location is crucial to UAV reconnaissance and target strikes. Traditional geo-location methods are highly dependent on the accuracies of GPS/INS and the target elevation, which restricts the target geo-location accuracy for LRORS. Moreover, due to the limitations of laser range and the common, real time methods of improving the accuracy, such as laser range finders, DEM and geographic reference data are inappropriate for long-range UAVs. To address the above problems, a set of work patterns and a novel geo-location method are proposed in this paper. The proposed method is not restricted by conditions such as the accuracy of GPS/INS, target elevation, and range finding instrumentation. Specifically, three steps are given, to perform as follows: First, calculate the rough geo-location of the target using the traditional method. Then, according to the rough geo-location, reimage the target. Due to errors in GPS/INS and target elevation, there will be a re-projection error between the actual points of the target and the calculated projection ones. Third, a weighted filtering algorithm is proposed to obtain the optimized target geo-location by processing the reprojection error. Repeat the above process until the target geo-location estimation converges on the true value. The geo-location accuracy is improved by the work pattern and the optimization algorithm. The proposed method was verified by simulation and a flight experiment. The results showed that the proposed method can improve the geo-location accuracy by 38.8 times and 22.5 times compared with traditional methods and DEM methods, respectively. The results indicate that our method is efficient and robust, and can achieve high-precision target geo-location, with an easy implementation.

4.
J Clin Pharm Ther ; 45(6): 1278-1287, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32557716

RESUMEN

WHAT IS KNOWN AND OBJECTIVES: Augmented renal clearance (ARC) is characterized by enhanced renal clearance, which leads to insufficient vancomycin exposure and treatment failure. In haematologic malignancy patients, determination of optimal vancomycin dosage is essential because of high stake of life-threatening bacterial infection and increased clearance. The aim of this study was to describe vancomycin pharmacokinetic parameters in haematologic malignancy with augmented renal clearance children and define the appropriate dosing regimen to achieve an AUC0-24h /MIC ≥400. METHODS: Hematologic malignancy with ARC children was enrolled in this retrospective study. The vancomycin PPK model was established by non-linear mixed-effects modelling programme. Goodness-of-fit (GOF) plots, non-parametric bootstrap, normalized prediction distribution error (NPDE) and visual predictive checks (VPCs) were carried out for internal evaluation of the final model. Monte Carlo simulation method was used to stimulate the optimal dosage regimens. RESULTS: Fifty-three patients with 106 samples were included. A one-compartment model with first-order elimination was developed, and the final model was as follows: CL (L/h) = 6.32×(WT/70)0.75  × e0.0467 ; V(L) = 39.6×(WT/70), where WT denotes weight (kg). The internal validation of the model showed a good prediction performance. Monte Carlo simulation results showed that when MIC was 0.5 mg/L or 1 mg/L, the recommended doses to achieve a target of AUC0-24h /MIC ≥400 were 25 to 40 and 50 to 75 mg/kg/d, respectively. With decreasing weight, the recommended dosage to achieve an AUC0-24h /MIC ≥400 increased. WHAT IS NEW AND CONCLUSION: A one-compartment vancomycin PPK model was established in haematologic malignancy with augmented renal clearance children with weight with allometric scaling as a significant covariate. When MIC was 1 mg/L, current recommended paediatric dosages were insufficient in haematologic malignancy with augmented renal clearance children and should be increased.


Asunto(s)
Antibacterianos/administración & dosificación , Neoplasias Hematológicas/patología , Modelos Biológicos , Vancomicina/administración & dosificación , Adolescente , Antibacterianos/farmacocinética , Área Bajo la Curva , Infecciones Bacterianas/tratamiento farmacológico , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Pruebas de Función Renal , Masculino , Pruebas de Sensibilidad Microbiana , Método de Montecarlo , Estudios Retrospectivos , Vancomicina/farmacocinética
5.
Opt Express ; 27(3): 1968-1980, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732242

RESUMEN

Combining the mathematical relationships between the grating wavefront and surfaces with the spatial relationships between the two grating wavefront, a mathematical model of the mosaicking errors is established to mosaic gratings. The five-dimensional mosaicking errors will respectively be calculated and then removed by the adjustment mechanisms. Mosaicking experiments are performed by using two gratings. First, by using zeroth order, the longitudinal offset is calculated and removed. Second, by using the diffraction order, the in-plane angle and grating spacing are calculated and removed, while the tip and tilt angles are calculated and removed. And then a mosaic grating is obtained.

6.
Pestic Biochem Physiol ; 121: 88-96, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26047115

RESUMEN

Carboxylesterases are mainly involved in the mediation of metabolic resistance of many insects to organophosphate (OP) insecticides. Carboxylesterases underwent two divergent evolutionary events: (1) quantitative mechanism characterized by the overproduction of carboxylesterase protein; and (2) qualitative mechanism caused by changes in enzymatic properties because of mutation from glycine/alanine to aspartate at the 151 site (G/A151D) or from tryptophan to leucine at the 271 site (W271L), following the numbering of Drosophila melanogaster AChE. Qualitative mechanism has been observed in few species. However, whether this carboxylesterase mutation mechanism is prevalent in insects remains unclear. In this study, wild-type, G/A151D and W271L mutant carboxylesterases from Culex pipiens and Aphis gossypii were subjected to germline transformation and then transferred to D. melanogaster. These germlines were ubiquitously expressed as induced by tub-Gal4. In carboxylesterase activity assay, the introduced mutant carboxylesterase did not enhance the overall carboxylesterase activity of flies. This result indicated that G/A151D or W271L mutation disrupted the original activities of the enzyme. Less than 1.5-fold OP resistance was only observed in flies expressing A. gossypii mutant carboxylesterases compared with those expressing A. gossypii wild-type carboxylesterase. However, transgenic flies universally showed low resistance to OP insecticides compared with non-transgenic flies. The flies expressing A. gossypii W271L mutant esterase exhibited 1.5-fold resistance to deltamethrin, a pyrethroid insecticide compared with non-transgenic flies. The present transgenic Drosophila system potentially showed that a quantitative increase in carboxylesterases induced broader resistance of insects to insecticides than a qualitative change.


Asunto(s)
Áfidos/enzimología , Carboxilesterasa , Culex/enzimología , Drosophila melanogaster , Resistencia a los Insecticidas , Insecticidas/farmacología , Animales , Animales Modificados Genéticamente , Áfidos/genética , Carboxilesterasa/genética , Carboxilesterasa/metabolismo , Culex/genética , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Femenino , Expresión Génica , Resistencia a los Insecticidas/genética , Resistencia a los Insecticidas/fisiología , Masculino , Mutación , Nitrilos/farmacología , Compuestos Organofosforados/farmacología , Piretrinas/farmacología
7.
Adv Mater ; 36(23): e2313198, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38413013

RESUMEN

Shape morphing in bistable kirigami enables remarkable functionalities appealing to a diverse range of applications across the spectrum of length scale. At the core of their shape shifting lies the architecture of their repeating unit, where highly deformable slits and quasi-rigid rotating units often exhibit multiple symmetries that confer isotropic deployment obeying uniform scaling transformation. In this work, symmetry breaking in bistable kirigami is investigated to access geometric frustration and anisotropic morphing, enabling arbitrarily scaled deployment in planar and spatial bistable domains. With an analysis on their symmetry properties complemented by a systematic investigation integrating semi-analytical derivations, numerical simulations, and experiments on elastic kirigami sheets, this work unveils the fundamental relations between slit symmetry, geometric frustration, and anisotropic bistable deployment. Furthermore, asymmetric kirigami units are leveraged in planar and flat-to-3D demonstrations to showcase the pivotal role of shear deformation in achieving target shapes and functions so far unattainable with uniformly stretchable kirigami. The insights provided in this work unveil the role of slit symmetry breaking in controlling the anisotropic bistable deployment of soft kirigami metamaterials, enriching the range of achievable functionalities for applications spanning deployable space structures, wearable technologies, and soft machines.

8.
J Microbiol Biotechnol ; 34(6): 1229-1238, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38755002

RESUMEN

This study aimed to develop and assess a chitosan biomedical antibacterial gel ZincOxide-GrapheneOxide/Chitosan/ß-Glycerophosphate (ZnO-GO/CS/ß-GP) loaded with nano-zinc oxide (ZnO) and graphene oxide (GO), known for its potent antibacterial properties, biocompatibility, and sustained drug release. ZnO nanoparticles (ZnO-NPs) were modified and integrated with GO sheets to create 1% and 3% ZnO-GO/CS/ß-GP thermo-sensitive hydrogels based on ZnO-GO to Chitosan (CS) mass ratio. Gelation time, pH, structural changes, and microscopic morphology were evaluated. The hydrogel's antibacterial efficacy against Porphyromonas gingivalis, biofilm biomass, and metabolic activity was examined alongside its impact (MC3T3-e1). The findings of this study revealed that both hydrogel formulations exhibited temperature sensitivity, maintaining a neutral pH. The ZnO-GO/CS/ß-GP formulation effectively inhibited P. gingivalis bacterial activity and biofilm formation, with a 3% ZnO-GO/CS/ß-GP antibacterial rate approaching 100%. MC3T3-e1 cells displayed good biocompatibility when cultured in the hydrogel extract.The ZnO-GO/CS/ß-GP thermo-sensitive hydrogel demonstrates favorable physical and chemical properties, effectively preventing P. gingivalis biofilm formation. It exhibits promising biocompatibility, suggesting its potential as an adjuvant therapy for managing and preventing peri-implantitis, subject to further clinical investigations.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Grafito , Hidrogeles , Porphyromonas gingivalis , Óxido de Zinc , Quitosano/química , Quitosano/farmacología , Óxido de Zinc/farmacología , Óxido de Zinc/química , Porphyromonas gingivalis/efectos de los fármacos , Grafito/química , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Ratones , Animales , Hidrogeles/química , Glicerofosfatos/química , Concentración de Iones de Hidrógeno , Temperatura , Pruebas de Sensibilidad Microbiana , Línea Celular , Nanopartículas/química
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(1): 221-226, 2023 Feb.
Artículo en Zh | MEDLINE | ID: mdl-36765503

RESUMEN

OBJECTIVE: To investigate the expression and its relative mechanism of hypoxia-inducible factor-1α(HIF-1α) in bone marrow(BM) of mice during G-CSF mobilization of hematopoietic stem cells (HSC) . METHODS: Flow cytometry was used to detect the proportion of Lin-Sca-1+ c-kit+ (LSK) cells in peripheral blood of C57BL/6J mice before and after G-CSF mobilization. And the expression of HIF-1α and osteocalcin (OCN) mRNA and protein were detected by RQ-PCR and immunohistochemistry. The number of osteoblasts in bone marrow specimens of mice was counted under the microscope. RESULTS: The proportion of LSK cells in peripheral blood began to increase at day 4 of G-CSF mobilization, and reached the peak at day 5, which was significantly higher than that of control group (P<0.05). There was no distinct difference in the expression of HIF-1α mRNA between bone marrow nucleated cells and osteoblasts of steady-state mice (P=0.073), while OCN mRNA was mainly expressed in osteoblasts, which was higher than that in bone marrow nucleated cells (P=0.034). After mobilization, the expression level of HIF-1α increased, but OCN decreased, and the number of endosteum osteoblasts decreased. The change of HIF-1α expression was later than that of OCN and was consistent with the proportion of LSK cells in peripheral blood. CONCLUSION: The expression of HIF-1α in bone marrow was increased during the mobilization of HSC mediated by G-CSF, and one of the mechanisms may be related to the peripheral migration of HSC induced by osteoblasts inhibition.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos , Movilización de Célula Madre Hematopoyética , Ratones , Animales , Factor Estimulante de Colonias de Granulocitos/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ratones Endogámicos C57BL , Células de la Médula Ósea/metabolismo , Osteocalcina/metabolismo , ARN Mensajero/metabolismo
10.
Zool Res ; 43(3): 391-403, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35362676

RESUMEN

In an attempt to generate g.A746G substitution in the BMPR-IB gene, we unexpectedly obtained BMPR-IB homozygous knockout piglets ( BMPR-IB -/-) and heterogeneous knockout piglets with one copy of the A746G mutation ( BMPR-IB -/746G) via CRISPR/Cas9 editing. Polymerase chain reaction (PCR) and sequencing revealed complex genomic rearrangements in the target region. All BMPR-IB-disrupted piglets showed an inability to stand and walk normally. Both BMPR-IB -/- and BMPR-IB -/746G piglets exhibited severe skeletal dysplasia characterized by distorted and truncated forearms (ulna, radius) and disordered carpal, metacarpal, and phalangeal bones in the forelimbs. The piglets displayed more severe deformities in the hindlimbs by visual inspection, including fibular hemimelia, enlarged tarsal bone, and disordered toe joint bones. Limb deformities were more profound in BMPR-IB -/- piglets than in the BMPR-IB -/746G piglets. Proteomic analysis identified 139 differentially expressed proteins (DEPs) in the hindlimb fibula of BMPR -IB -/746G piglets compared to the wild-type (WT) controls. Most DEPs are involved in skeletal or embryonic development and/or the TGF-ß pathway and tumor progression. Gene Ontology (GO) and protein domain enrichment analysis suggested alterations in these processes. Of the top 50 DEPs, a large proportion, e.g., C1QA, MYO1H, SRSF1, P3H1, GJA1, TCOF1, RBM10, SPP2, MMP13, and PHAX, were significantly associated with skeletal development. Our study provides novel findings on the role of BMPR-IB in mammalian limb development.


Asunto(s)
Genómica , Proteómica , Animales , Extremidades , Femenino , Mamíferos , Embarazo , Porcinos/genética
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(1): 292-297, 2022 Feb.
Artículo en Zh | MEDLINE | ID: mdl-35123642

RESUMEN

OBJECTIVE: To analyze the clinical characteristics of bloodstream infection (BSI) in patients treated by hematopoietic stem cell transplantation (HSCT). METHODS: The clinical characteristics, distribution of pathogenic bacteria causing BSI and drug sensitivity of 910 patients treated by HSCT in our department from January 2013 to June 2020 were retrospectively analyzed. RESULTS: Among 910 HSCT patients, 111 patients were diagnosed as BSI within 100 days after transplantation, and 98 patients showed BSI during the period of agranulocytosis. Multivariate analysis showed that the usage of anti-thymocyte globulin (ATG), long duration of agranulocytosis and low infusion volume of mononuclear cell (MNC) were the independent risk factors affecting BSI after HSCT. Among 121 pathogenic bacteria isolated, 76 Gram-negative (G-) bacteria (62.8%), 40 Gram-positive (G+) bacteria (33.0%), and 5 fungi (4.1%) were detected out. The top three pathogens were Escherichia coli, Staphylococcus epidermidis and Pseudomonas aeruginosa. The drug-resistance rates of Escherichia coli and Klebsiella pneumoniae to carbapenems was 14.3% and 7.7%, respectively, and Pseudomonas aeruginosa was 66.7%. The susceptibility of G+ bacteria to vancomycin, linezolid and teicoplanin was 97.5%, 100% and 100%, respectively. The crude mortality rate of the patients with BSI at 100 days after HSCT was significantly higher than that of patients without BSI (P<0.001). CONCLUSION: The usage of ATG, long duration of agranulocytosis and low infusion volume of MNC are independent risk factors for BSI after HSCT. The pathogens after HSCT are mainly G- bacteria. Pseudomonas aeruginosa is highly resistant to carbapenems. Key words  ;


Asunto(s)
Bacteriemia , Trasplante de Células Madre Hematopoyéticas , Sepsis , Bacteriemia/epidemiología , Bacterias , Humanos , Estudios Retrospectivos
12.
Adv Sci (Weinh) ; 8(15): e2100445, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34061464

RESUMEN

Rapid motion in soft pneumatic robots is typically achieved through actuators that either use a fast volume input generated from pressure control, employ an integrated power source, such as chemical explosions, or are designed to embed elastic instabilities in the body of the robot. This paper presents a bi-shell valve that can fast actuate soft actuators neither relying on the fast volume input provided by pressure control strategies nor requiring modifications to the architecture of the actuator. The bi-shell valve consists of a spherical cap and an imperfect shell with a geometrically tuned defect that enables shell snapping interaction to convert a slowly dispensed volume input into a fast volume output. This function is beyond those of current valves capable to perform fluidic flow regulation. Validated through experiments, the analysis unveils that the spherical cap sets the threshold of the snapping pressure along with the upper bounds of volume and energy output, while the imperfect shell interacts with the cap to store and deliver the desired output for rapid actuation. Geometry variations of the bi-shell valve are provided to show that the concept is versatile. A final demonstration shows that the soft valve can quickly actuate a striker.

13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 43(5): 390-4, 2009 May.
Artículo en Zh | MEDLINE | ID: mdl-19534992

RESUMEN

OBJECTIVE: To investigate the heterozygous genotype and molecular characteristics of Organophosphorus resistance associated with heterozygous Estbeta2 of esterase B2 gene from natural population of Culex pipiens complex. METHODS: Genomic DNA was extracted from natural populations of Culex pipiens complex in Hangzhou. The PCR-restriction fragment length polymorphism (PCR-RFLP) assay was applied to type the resistance associated esterase gene. Estbeta2 of esterase B2 gene was identified by PCR-RFLP, and the genotyping for heterozygous Estbeta2 was carried out after restriction enzyme digesting by Bfm I endonuclease. RESULTS: The DNA was isolated from 207 Culex pipiens respectively, while 156 PCR samples showed positive and the positive rate was 75.36% (156/207). The PCR-RFLP assay of esterase B2 gene revealed that the Estbeta2 was accounted about 28.20% (44/156) in 156 positive samples. There were two genotypes identified, namely homozygous Estbeta2 (90.90%, 30/33) and heterozygous Estbeta2 (9%, 3/33), heterozygous Estbeta2 was in existence of a hybrid form as which combined with Estbeta2 and a subtype (Estbeta2/Estbeta2(1)). CONCLUSION: Heterozygous Estbeta2 of Organophosphorus resistance associated with esterase genotype was determined in natural population of Culex pipiens, and a genotyping method was established.


Asunto(s)
Culex/enzimología , Heterocigoto , Resistencia a los Insecticidas/genética , Serina Endopeptidasas/genética , Animales , Culex/genética , Genes de Insecto , Genotipo , Insecticidas/farmacología , Compuestos Organofosforados/farmacología , Fenotipo
14.
Sci Rep ; 9(1): 19499, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-31862936

RESUMEN

Shape morphing in response to an environmental stimulus, such as temperature, light, and chemical cues, is currently pursued in synthetic analogs for manifold applications in engineering, architecture, and beyond. Existing strategies mostly resort to active, namely smart or field responsive, materials, which undergo a change of their physical properties when subjected to an external stimulus. Their ability for shape morphing is intrinsic to the atomic/molecular structure as well as the mechanochemical interactions of their constituents. Programming shape changes with active materials require manipulation of their composition through chemical synthesis. Here, we demonstrate that a pair of off-the-shelf passive solids, such as wood and silicone rubber, can be topologically arranged in a kirigami bi-material to shape-morph on target in response to a temperature stimulus. A coherent framework is introduced to enable the optimal orchestration of bi-material units that can engage temperature to collectively deploy into a geometrically rich set of periodic and aperiodic shapes that can shape-match a predefined target. The results highlight reversible morphing by mechanics and geometry, thus contributing to relax the dependence of current strategies on material chemistry and fabrication.

15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1774-1778, 2019 Dec.
Artículo en Zh | MEDLINE | ID: mdl-31839037

RESUMEN

OBJECTIVE: To investigate the clinical characteristics, etiology and drug susceptibility of bacterial bloodstream infections in acute leukemia(AL) patients. METHODS: Clinical data, etiology and drug susceptibility of acute leukemia patients with bacterial bloodstream infections from April 2009 to April 2018 were retrospectively analyzed. RESULTS: A total of 376 strains were isolated, 76.9% was Gram-negative bacterial and 23.1% was Gram-positive bacteria. Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae were listed as the top three of Gram-negative bacteria. The susceptibility of Escherichia coli to the tigacycline, imipenem and meropenem was 100.0%, 98.2% and 98.1%, respectively. The susceptibility of Klebsiella pneumoniae to the tigacycline, imipenem and meropenem were 100.0%, 98.3% and 94.4%, respectively. The adjustment rate for initial use of carbopenems was 3.8%, while the adjustment rate for initial use of noncarbopenems was 74.3% in patients with main Gram-negative bacterial blood stream infection. The susceptibility of Gram-positive bacteria to glycopeptide antibiotics, linezolid and tigacycline was 100.0%. CONCLUSION: Gram-negative bacteria is the majority type of bacteria in AL patients with bacteria blood stream infections. The susceptibility of Gram-negative bacteria to the carbapenems is high, and the treatment adjustment rate is obviously low. The glycopeptide, linezolid and tigacycline are effective for Gram-positive bacteria infections..


Asunto(s)
Bacteriemia , Bacterias Gramnegativas , Bacterias Grampositivas , Humanos , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos
16.
FASEB J ; 21(13): 3584-91, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17567568

RESUMEN

Carboxylesterase-based metabolic resistance to organophosphates (OPs) in insects has been shown to originate either from mutations in esterase-encoding sequences or from amplification of esterase genes. This study aimed to test the hypothesis that mosquitoes can acquire OP resistance by functional changes in carboxylesterases. Mutations were introduced into the esterase B1 of mosquito Culex pipiens by site-directed mutagenesis at positions 110 and 224. Three single mutants (G110D, W224L, and W224S) and two double mutants (G110D/W224L and G110D/W224S) were expressed and purified. All five mutants lost native carboxylesterase activity. Mutation W224L converted esterase B1 to an OP hydrolase and increased its malathion carboxylesterase activity. No obvious OP hydrolysis was observed by G110D or W224S. Our data strongly support our hypothesis and suggest that mutation W224L might occur in natural populations of mosquitoes. Sequence comparison shows that the site 224 is especially highly conserved among various insect carboxylesterases. This leads to another hypothesis: that the position 224 plays a key role in insect carboxylesterases' switching from their native physiological functions to other functional niches under selection pressure exerted by insecticides.


Asunto(s)
Hidrolasas de Éster Carboxílico/metabolismo , Culex/fisiología , Resistencia a los Insecticidas , Compuestos Organofosforados/toxicidad , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/genética , Datos de Secuencia Molecular , Filogenia , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Especificidad de la Especie
17.
Zhonghua Yi Xue Za Zhi ; 88(4): 254-7, 2008 Jan 22.
Artículo en Zh | MEDLINE | ID: mdl-18361837

RESUMEN

OBJECTIVE: To investigate the effects of different treatment protocols on non-Hodgkin's lymphoma (NHL) with bone marrow involvement (BMI). METHODS: The clinical data of 148 patients of NHL with BMI, 108 undergoing CHOP regimen, 51 undergoing dose-intensive CHOP regimens, 13 undergoing CHOP regimen + rituximab, and 27 undergoing hemopoietic stem cell transplantation (HSCT) after CHOP protocol with remission. The curative effects were retrospectively analyzed. RESULTS: (1) The response rate (RR) for the whole group was 80.4%, with a complete remission (CR) rate of 60.7%. The response rate of the patients treated with the dose-intensive regimens (dose-intensive group) was 84.3%, significantly higher than that of the patients treated with standard CHOP regimen (64.1%, P < 0.05). (2) The 3- and 5-year overall survival (OS) rates and progress-free survival (PFS) of the B-cell NHL patients who underwent HSCT + Rituximab treatment (Rituximab combined with chemotherapy) were significantly higher than those of the dose-intensive group and CHOP group, and the 3- and 5-year OS rates and PFS of the dose-intensive group were all significantly higher than those of the CHOP group (all P < 0.05). (3) The 3- and 5-year OS rates, and PFS of the T-cell NHL patients who underwent HSCT group and dose-intensive CHOP were all significantly higher than those patients who underwent CHOP regimen (all P < 0.05). CONCLUSION: Superior survival may benefit from Dose-intensive regimens and HSCT, may be good choices for the patients with NHLBMI, a group of heterogeneous malignancies with poor prognosis. And combined chemotherapy with Rituximab treatment remarkably raises the effect for CD20(+) B-cell NHLBMI.


Asunto(s)
Médula Ósea/patología , Linfoma no Hodgkin/patología , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Niño , Preescolar , Terapia Combinada , Ciclofosfamida , Doxorrubicina , Femenino , Estudios de Seguimiento , Trasplante de Células Madre Hematopoyéticas , Humanos , Estimación de Kaplan-Meier , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/cirugía , Masculino , Persona de Mediana Edad , Prednisona , Resultado del Tratamiento , Vincristina , Adulto Joven
18.
Leuk Res ; 31(6): 765-71, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17007927

RESUMEN

This study was aimed to investigate the factors influencing long-term survival on patients with acute promyelocytic leukemia. Here, we present a single center retrospective study with long-term follow-up to explore the prognostic factors and a rationale of the using of ATRA, chemotherapy and As(2)O(3) in the treatment of newly diagnosed APL patients. In total, 222 patients, 184 achieved complete remission (CR) with the CR rate of 82.88% and 22 patients died during early induction therapy with the early-death-rate of 10%. Total 171 newly diagnosed APL patients entering CR were retrospectively analyzed from November 1989 to December 2004,with a median follow-up of 36 months (6-185 months). Univariate and multivariate analysis of eight factors potentially influencing survival and prognosis were carried out with Log-Rank and Cox regression method, including sex, age, initial WBC count, the level of lactic dehydrogenase (LDH), first induction regimen, days from induction therapy to CR, post-remission therapy and the status of PML-RAR alpha fusion gene by reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the estimated 5-year overall survival (OS) and relapse-free survival (RFS) were 80.9+/-4.0 and 71.0+/-4.0%, respectively. Univariate analyses showed that initial WBC count, first induction regimen, days from induction therapy to CR, post-remission therapy regimen and the status of PML-RAR alpha in remission were important prognostic factors for long-term survival. Multivariate study showed that only post-remission therapy regimen was associated with RFS and OS. It is concluded that the post-remission treatment combining ATRA, As(2)O(3) and chemotherapy would significantly improve the long-term survival of APL patients achieving CR(1).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/mortalidad , Adolescente , Adulto , Trióxido de Arsénico , Arsenicales/administración & dosificación , Niño , Preescolar , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Leucemia Promielocítica Aguda/genética , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Óxidos/administración & dosificación , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Tretinoina/administración & dosificación
19.
Insect Biochem Mol Biol ; 37(11): 1131-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17916499

RESUMEN

In the mosquito Culex pipiens complex (Diptera: Culicidae), the amplification of carboxylesterase genes is an important mechanism providing resistance to organophosphate insecticides. Various amplified alleles at the Ester locus have been identified over the world. In this study, two newly detected Ester alleles, Ester(B10) and Ester(11) (including associated Ester(A11) and Ester(B11)), coding for esterases B10 and A11-B11, respectively, are characterized qualitatively and quantitatively. A high molecular identity is observed both at the nucleotide level and at the deduced amino acid level among the known Ester alleles. Real-time quantitative PCR results suggest 2.5-fold amplification of the Ester(B10) allele, 36.5-fold amplification of the Ester(A11) allele, and 19.1-fold amplification of the Ester(B11) allele. The ca. 2-fold difference in amplification level between Ester(A11) and Ester(B11) may indicate a new model for the esterase amplification. Bioassays show that these two resistant Ester alleles only can confer moderate or low resistance to the tested organophosphate insecticides.


Asunto(s)
Culex/enzimología , Esterasas/genética , Proteínas de Insectos/genética , Insecticidas , Organofosfatos , Alelos , Animales , Clonación Molecular , Culex/genética , Electroforesis , Esterasas/metabolismo , Esterasas/fisiología , Proteínas de Insectos/metabolismo , Proteínas de Insectos/fisiología , Resistencia a los Insecticidas/genética , Análisis de Secuencia de ADN
20.
Pest Manag Sci ; 63(5): 453-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17387711

RESUMEN

Seven field populations of mosquito Culex pipiens complex (Diptera: Culicidae) were collected from four provinces of China. The resistance status of larvae to dichlorvos, parathion, chlorpyrifos, fenobucarb (BPMC) and propoxur were determined by bioassays, disclosing that they were more resistant to organophosphate (moderate or low resistance) than to carbamate (low or no significant resistance) insecticides. Starch gel electrophoresis confirmed the presence and distribution of overproduced esterases B1, A2-B2, A8-B8 and A9-B9, the frequencies of which varied according to their regional origins. Electrophoretic polymorphism at four putatively neutral loci (got-1, got-2, pgi and pgm) showed that the overall genetic differentiation found across all populations was significantly large (Fst = 0.28, P < 10(-4)), and genetic exchange was slightly restricted by distance isolation (P = 0.018).


Asunto(s)
Culex , Filariasis/transmisión , Insectos Vectores/efectos de los fármacos , Resistencia a los Insecticidas , Insecticidas , Migración Animal , Animales , China , Culex/genética , Culex/crecimiento & desarrollo , Culex/fisiología , Esterasas/genética , Genotipo , Humanos , Resistencia a los Insecticidas/genética , Insecticidas/química , Insecticidas/clasificación , Larva/efectos de los fármacos
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