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1.
J Nat Prod ; 85(1): 256-263, 2022 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-35042332

RESUMEN

Vicenistatin (1) is a potent polyketide antitumor antibiotic composed of a 20-membered macrolactam core appended to a unique aminosugar, vicenisamine. In this study, vicenistatin was isolated and its biosynthetic gene cluster identified from Monodonata labio-associated Streptomyces parvus SCSIO Mla-L010. A set of five genes, vicC, vicD, vicE, vicF, and vicG, was confirmed to be involved in the biosynthesis of the aminosugar by gene inactivations. VicG was characterized as an N-methyltransferase that catalyzes the methylation of the 4'-amino group in the last step of the aminosugar biosynthetic pathway; the N-demethyl intermediate 4'-N-demethylvicenistatin (2) was isolated from the ΔvicG mutant strain. In addition, vicR1 was characterized as a positive pathway-specific regulatory gene. Notably, N-demethyl compound 2 was found to exert impressive antibacterial activities, with MIC values spanning 0.06-4 µg/mL, against a panel of Gram-positive bacteria including methicillin-resistant Staphylococcus aureus, Gram-negative Helicobacter pylori, and mycobacterium Mycobacterium smegmatis and the fungal pathogen Candida albicans. Compound 2 was also found to display reduced cytotoxicities relative to vicenistatin, especially against noncancerous human cell lines.


Asunto(s)
Amino Azúcares/metabolismo , Aminoglicósidos/farmacología , Gastrópodos/microbiología , Genes Reguladores , Lactamas/farmacología , Macrólidos/farmacología , Streptomyces/genética , Animales , Vías Biosintéticas/genética , Línea Celular Tumoral , Xenoinjertos , Humanos , Ratones
2.
Plasmid ; 116: 102577, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34058238

RESUMEN

Proteins from food-grade expression systems can be used in food products and medical applications. Herein, we describe a one-step method of constructing an expression vector in Kluyveromyces lactis by combining a URA3-deficient strain and a plasmid vector with no drug-resistant selection. Adjacent DNA elements of the vector were assembled in a targeted manner through a reaction with a special recombinase to form a plasmid vector using a one-step reaction. The unnecessary fragments containing the pUC origin and the ampicillin resistance gene were removed, and the vector was isolated and purified before transformation. A single transformation of the vector can produce a URA3-deficient strain. PCR assay, sequencing, and western blot analysis all indicated that the method of vector construction and target protein expression (mCherry and human serum albumin) were successful. This method may potentially be applied to any species containing the URA3 gene; this system has the potential to become a safe and powerful tool for promoting protein expression in food-safe species.


Asunto(s)
Kluyveromyces , Vectores Genéticos/genética , Humanos , Kluyveromyces/genética , Plásmidos/genética , Transformación Genética
3.
Plasmid ; 79: 15-21, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25681561

RESUMEN

In order to clone PCR products and express them effectively in Escherichia coli, a directional cloning system was constructed by generating a T vector based on pQE-30Xa. The vector was prepared by inserting an XcmI cassette containing an endonuclease XcmI site, a kanamycin selective marker, a multiple-cloning-site (MCS) region and an opposite endonuclease XcmI site into the vector pQE-30Xa. The T vector pQE-T with single overhanging dT residues at both 3' ends was obtained by digesting with the restriction enzyme XcmI. For directional cloning, a BamHI site was introduced to the ends of the PCR products. A BamHI site was also located on the multiple cloning site of pQE-T. The PCR products were ligated with pQE-T. The directionally inserted recombinants were distinguished by using BamHI to digest the recombinants because there are two BamHI sites located on the both sides of PCR fragment. In order to identify the T-vector functions, the 14-3-3-ZsGreen and hRBP genes were amplified and a BamHI site was added to the ends of the genes to confirm this vector by ligation with pQE-T. Results showed that the 14-3-3-ZsGreen and hRBP were cloned to the vector pQE-T directly and corresponding proteins were successfully produced. It was here demonstrated that this directional vector is capable of gene cloning and is used to manipulate gene expression very easily. The methodology proposed here involves easy incorporation of the construct into other vectors in various hosts.


Asunto(s)
Clonación Molecular , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Escherichia coli/genética , Genes Bacterianos , Vectores Genéticos , Secuencia de Bases , ADN Bacteriano/genética , Electroforesis en Gel de Poliacrilamida , Regulación Bacteriana de la Expresión Génica , Marcadores Genéticos , Kanamicina/farmacología , Datos de Secuencia Molecular , Plásmidos/genética , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
4.
ScientificWorldJournal ; 2014: 756178, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24715818

RESUMEN

In mass customization logistics service, reasonable scheduling of the logistics service supply chain (LSSC), especially time scheduling, is benefit to increase its competitiveness. Therefore, the effect of a customer order decoupling point (CODP) on the time scheduling performance should be considered. To minimize the total order operation cost of the LSSC, minimize the difference between the expected and actual time of completing the service orders, and maximize the satisfaction of functional logistics service providers, this study establishes an LSSC time scheduling model based on the CODP. Matlab 7.8 software is used in the numerical analysis for a specific example. Results show that the order completion time of the LSSC can be delayed or be ahead of schedule but cannot be infinitely advanced or infinitely delayed. Obtaining the optimal comprehensive performance can be effective if the expected order completion time is appropriately delayed. The increase in supply chain comprehensive performance caused by the increase in the relationship coefficient of logistics service integrator (LSI) is limited. The relative concern degree of LSI on cost and service delivery punctuality leads to not only changes in CODP but also to those in the scheduling performance of the LSSC.


Asunto(s)
Equipos y Suministros/provisión & distribución , Modelos Teóricos , Estudios de Tiempo y Movimiento
5.
IEEE Trans Vis Comput Graph ; 30(5): 2849-2859, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38437108

RESUMEN

Point cloud video (PCV) offers watching experiences in photorealistic 3D scenes with six-degree-of-freedom (6-DoF), enabling a variety of VR and AR applications. The user's Field of View (FoV) is more fickle with 6-DoF movement than 3-DoF movement in 360-degree video. PCV streaming is extremely bandwidth-intensive. However, current streaming systems require hundreds of Mbps bandwidth, exceeding the bandwidth capabilities of commodity devices. To save bandwidth, FoV-adaptive streaming predicts a user's FoV and only downloads point cloud data falling in the predicted FoV. But it is difficult to accurately predict the user's FoV even 2-3 seconds before playback due to 6-DoF. Misprediction of FoV or network bandwidth dips results in frequent stalls. To avoid rebuffering, existing systems would cause incomplete FoV and degraded experience, deteriorating the user's quality of experience (QoE). In this paper, we describe Fumos, a novel system that preserves interactive experience by avoiding playback stalls while maintaining high perceptual quality and high compression rate. We find a research gap in inter-frame redundant utilization and progressive mechaism. Fumos has three crucial designs, including (1) Neural compression framework with inter-frame coding, namely N-PCC, which achieves both bandwidth efficiency and high fidelity. (2) Progressive refinement streaming framework that enables continuous playback by incrementally upgrading a fetched portion to a higher quality (3) System-level adaptation that employs Lyapunov optimization to jointly optimize the long-term user QoE. Experimental results demonstrate that Fumos significantly outperforms Draco, achieving an average decoding rate acceleration of over 260×. Moreover, the proposed compression framework N-PCC attains remarkable BD-Rate gains, averaging 91.7% and 51.7% against the state-of-the-art point cloud compression methods G-PCC and V-PCC, respectively.

6.
World J Pediatr ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713366

RESUMEN

BACKGROUND: SARS-CoV-2 continues to mutate over time, and reports on children infected with Omicron BA.5 are limited. We aimed to analyze the specific symptoms of Omicron-infected children and to improve patient care. METHODS: We selected 315 consecutively hospitalized children with Omicron BA.5 and 16,744 non-Omicron-infected febrile children visiting the fever clinic at our hospital between December 8 and 30, 2022. Specific convulsions and body temperatures were compared between the two cohorts. We analyzed potential associations between convulsions and vaccination, and additionally evaluated the brain damage among severe Omicron-infected children. RESULTS: Convulsion rates (97.5% vs. 4.3%, P < 0.001) and frequencies (median: 2.0 vs. 1.6, P < 0.001) significantly differed between Omicron-infected and non-Omicron-infected febrile children. The body temperatures of Omicron-infected children were significantly higher during convulsions than when they were not convulsing and those of non-Omicron-infected febrile children during convulsions (median: 39.5 vs. 38.2 and 38.6 °C, both P < 0.001). In the three Omicron-subgroups, the temperature during convulsions was proportional to the percentage of patients and significantly differed ( P < 0.001), while not in the three non-Omicron-subgroups ( P = 0.244). The convulsion frequency was lower in the 55 vaccinated children compared to the 260 non-vaccinated children (average: 1.8 vs. 2.1, P < 0.001). The vaccination dose and convulsion frequency in Omicron-infected children were significantly correlated ( P < 0.001). Fifteen of the 112 severe Omicron cases had brain damage. CONCLUSIONS: Omicron-infected children experience higher body temperatures and frequencies during convulsions than those of non-Omicron-infected febrile children. We additionally found evidence of brain damage caused by infection with omicron BA.5. Vaccination and prompt fever reduction may relieve symptoms.

7.
Front Physiol ; 13: 792292, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295586

RESUMEN

The treatment and prevention of hypertension has been a worldwide medical challenge. The key pathological hallmark of hypertension is altered arterial vascular structure and function, i.e., increased peripheral vascular resistance due to vascular remodeling. The aim of this review is to elucidate the molecular mechanisms of vascular remodeling in hypertension and the protective mechanisms of aerobic exercise against vascular remodeling during the pathological process of hypertension. The main focus is on the mechanisms of oxidative stress and inflammation in the pathological condition of hypertension and vascular phenotypic transformation induced by the trilaminar structure of vascular endothelial cells, smooth muscle cells and extracellular matrix, and the peripheral adipose layer of the vasculature. To further explore the possible mechanisms by which aerobic exercise ameliorates vascular remodeling in the pathological process of hypertension through anti-proliferative, anti-inflammatory, antioxidant and thus inhibiting vascular phenotypic transformation. It provides a new perspective to reveal the intervention targets of vascular remodeling for the prevention and treatment of hypertension and its complications.

8.
Biomolecules ; 13(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36671438

RESUMEN

Fabry disease (FD) is a progressive multisystemic disease characterized by lysosomal enzyme deficiency. Enzyme replacement therapy (ERT) is one of the most significant advancements and breakthroughs in treating FD. However, limited resources and the high cost of ERT might prevent patients from receiving prompt and effective therapy, thereby resulting in severe complications. Future progress in ERT can uncover promising treatment options. In this study, we developed and validated a recombinant enzyme (Lanzyme) based on a CHO-S cell system to provide a new potential option for FD therapy. Our results indicated that Lanzyme was heavily glycosylated, and its highest activity was similar to a commercial enzyme (Fabrazyme®). Our pharmacokinetic assessment revealed that the half-life of Lanzyme was up to 11 min, which is nearly twice that of the commercial enzyme. In vivo experiments revealed that Lanzyme treatment sharply decreased the accumulation levels of Gb3 and lyso-Gb3 in various tissues of FD model mice, with superior or comparable therapeutic effects to Fabrazyme®. Based on these data, Lanzyme may represent a new and promising treatment approach for FD. Building this enzyme production system for ERT can offer additional choice, potentially with enhanced efficacy, for the benefit of patients with FD.


Asunto(s)
Terapia de Reemplazo Enzimático , Enfermedad de Fabry , Proteínas Recombinantes , alfa-Galactosidasa , Animales , Ratones , alfa-Galactosidasa/uso terapéutico , Enfermedad de Fabry/tratamiento farmacológico , Proteínas Recombinantes/uso terapéutico
9.
Theranostics ; 10(3): 1332-1354, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31938068

RESUMEN

Lipid oversupply may induce CD36 sarcolemmal translocation to facilitate fatty acid transport, which in turn causes dyslipidemia and type 2 diabetes. However, the underlying mechanisms of CD36 redistribution are still yet to be unraveled. Methods: High fat diet fed mice and palmitate/oleic acid-treated L6 cells were used to investigate the initial events of subcellular CD36 recycling prior to insulin resistance. The regulation of CD36 sarcolemmal translocation by lipid oversupply was assessed by insulin tolerance test (ITT), oral glucose tolerance test (OGTT), glucose/fatty acid uptake assay, surface CD36 and GLUT4 detection, and ELISA assays. To elucidate the underlying mechanisms, specific gene knockout, gene overexpression and/or gene inhibition were employed, followed by Western blot, co-immunoprecipitation, immunostaining, and kinase activity assay. Results: Upon lipid/fatty acid overload, PKCζ activity and TBC1D1 phosphorylation were enhanced along with increased sarcolemmal CD36. The inhibition of PKCζ or TBC1D1 was shown to block fatty acid-induced CD36 translocation and was synergistic in impairing CD36 redistribution. Mechanically, we revealed that AMPK was located upstream of PKCζ to control its activity whereas Rac1 facilitated PKCζ translocation to the dorsal surface of the cell to cause actin remodeling. Furthermore, AMPK phosphorylated TBC1D1 to release retained cytosolic CD36. The activated PKCζ and phosphorylated TBC1D1 resulted in a positive feedback regulation of CD36 sarcolemmal translocation. Conclusion: Collectively, our study demonstrated exclusively that lipid oversupply induced CD36 sarcolemmal translocation via dual modulation of PKCζ and TBC1D1, which was as an early event prior to insulin resistance. The acquired data may provide potential therapy targets to prevent lipid oversupply-induced insulin resistance.


Asunto(s)
Antígenos CD36/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos/administración & dosificación , Resistencia a la Insulina , Sarcolema/metabolismo , Animales , Línea Celular , Dieta Alta en Grasa , Proteínas Activadoras de GTPasa/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Células Musculares , Proteína Quinasa C-theta/metabolismo , Transporte de Proteínas , Ratas
10.
Biomed Pharmacother ; 129: 110425, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32570123

RESUMEN

Acute leukemia is a common hematological malignancy. Despite recent promising progress, the prognosis of acute leukemia patients remains to be improved. New therapies are therefore still needed. Salmonella typhimurium has been shown to be highly effective as an anti-tumor agent in many solid cancer models, but it has not been applied in acute leukemia. Here, we report an attenuated Salmonella typhimurium strain, VNP20009, can induce apoptosis in multiple types of leukemia cells both in vivo and in vitro. Furthermore, VNP20009 significantly inhibited the proliferation of MLL-AF9-induced acute myeloid leukemia cells and prolonged the survival of the AML-carrying mice. VNP20009 restored the counts of white blood cell (WBC) and its five subsets in peripheral blood (PB) to near-physiological values, and elevated the levels of certain cytokines, such as tumor necrosis factor-α (TNF-α), leukemia inhibitory factor (LIF), interferon-γ (IFN-γ), chemokine C-X-C motif ligand-10 (CXCL-10) and C-C motif ligand-2 (CCL-2). Moreover, the ratio of immune cells, including natural killer cells (NKs), CD4+ Th1-type cells and CD8+ IFN-γ-producing effector T cells were highly upregulated in the AML mice treated with VNP20009. The results of the present study potentially provide an alternative therapeutic strategy for hematologic malignancies through boosting the innate and adaptive anti-tumor immunity.


Asunto(s)
Antineoplásicos/farmacología , Vacunas Bacterianas/farmacología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Inmunidad Adaptativa/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Proliferación Celular/efectos de los fármacos , Citocinas/sangre , Células HL-60 , Humanos , Inmunidad Innata/efectos de los fármacos , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células T Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(7): 924-928, 2017 Jul 20.
Artículo en Zh | MEDLINE | ID: mdl-28736369

RESUMEN

OBJECTIVE: To investigate the significance of early screening of pediatric developmental dysplasia of the hip (DDH) and congenital muscular torticollis (CMT) using ultrasonography and establish a simultaneous screening model for pediatric DDH and CMT. METHODS: From January, 2013 to January, 2016, a total of 5060 pediatric patients with suspected DDH and CMT underwent ultrasonic examinations. The diagnostic results of the two diseases were classified into different clinical types, and Chi-square test was used to analyze the one-way relationship between different types of DDH and CMT; correspondence analysis was used for multivariate analysis of the variables. Chi-square test was used to analyze the difference between the detection rates in suspected CMT patients and the normal population. RESULTS: GrafIIa type DDH was associated with mass-type CMT in the children (χ2=331.800, P<0.001). DDH of GrafIIb, GrafIIc, Graf III, and Graf IV types were related with non-tumor type of CMT. The children with a suspected diagnosis of CMT showed a significantly higher detection rate of DDH than the normal subjects (χ2=321.889, P<0.001). CONCLUSION: DDH is closely related with CMT. Early simultaneous screening of DDH and CMT can help to improve the early diagnosis rate of CMT in children.

12.
Artículo en Zh | MEDLINE | ID: mdl-27097486

RESUMEN

OBJECTIVE: To explore the relationship between the hepatobiliary pathological changes under B-ultrasound examinations and Clonorchis sinensis infection, so as to provide the evidence for further prevention and control. METHODS: The stool test and ELISA were applied to test the pathogeny and antibody to C. sinensis of the suspicious patients who had the hepatobiliary pathological changes under B-ultrasound examinations in People's Hospital of Wuxuan County from Jan. 2010 to Dec. 2013. RESULTS: Totally 113 suspicious patients of C. sinensis infection were investigated, and the positive rates of egg and serum antibody were 64.60% (73 cases) and 66.37% (75 cases) respectively. The positive rates of the male and those aged ≥ 50 years were significantly higher than those of the female and the cases younger than 50 years respectively (χ² = 3.554, 6.267, both P < 0.05). In the C. sinensis infected patients, the degree of pathological changes of hepatobiliary was positively correlated with the infectiosity of C. sinensis (χ² = 64.952, P < 0.01). CONCLUSION: The hepatobiliary pathological changes under B-ultrasound examinations may be resulted from the infection of C. sinensis, and the patients with the changes should be further investigated for the pathogen and antibody to C. sinensis.


Asunto(s)
Clonorquiasis/diagnóstico por imagen , Clonorchis sinensis/fisiología , Hígado/patología , Adulto , Anciano , Animales , Anticuerpos Antihelmínticos/sangre , China , Clonorquiasis/sangre , Clonorquiasis/parasitología , Clonorquiasis/patología , Femenino , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Ultrasonografía , Adulto Joven
13.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 29(12): 1064-6, 1070, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26513991

RESUMEN

OBJECTIVE: To evaluate the efficacy of chinese traditional treatment after functional endoscopic sinus surgery (FESS) for patients with chronic sinusitis. METHOD: Eighty-eight cases of patients with chronic sinusitis were randomly divided into control group and treatment group after FESS and followed for 3 months. The control group received routine treatment. The treatment group received Chinese traditional treatment on the basis of routine treatment. VAS scores, Lund-Kennedy scores and Lund-Mackay scores were employed to conduct the subjective and objective assessment, comprehensively evaluate the clinical efficacy before and after treatment. RESULT: (1) After 3 months of treatment, the two groups of VAS scores and Lund-Mackay scores were significantly improved before treatment (P<0. 05). (2)After 3 months of treatment, the effectiveness of the control group was 81. 8%, treatment group was 97. 7%, the difference was statistically significant(P<0. 05). CONCLUSION: Chinese traditional treatment after FESS can reduce postoperative mucosal edema and promote the postoperative recovery of sinus mucosal inflammation, is effective in preventing the recurrence of postoperative.


Asunto(s)
Medicina Tradicional China , Senos Paranasales/cirugía , Sinusitis/tratamiento farmacológico , Sinusitis/cirugía , Enfermedad Crónica , Endoscopía , Humanos , Periodo Posoperatorio , Resultado del Tratamiento
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