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1.
Atherosclerosis ; 391: 117478, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417185

RESUMEN

BACKGROUND AND AIMS: Atherosclerosis (AS) is a chronic inflammatory disease characterized by lipid infiltration and plaque formation in blood vessel walls. Ganoderic acids (GA), a class of major bioactive compounds isolated from the Chinese traditional medicine Ganoderma lucidum, have multiple pharmacological activities. This study aimed to determine the anti-atherosclerotic effect of GA and reveal the pharmacological mechanism. METHODS: ApoE-/- mice were fed a high-cholesterol diet and treated with GA for 16 weeks to induce AS and identify the effect of GA. Network pharmacological analysis was performed to predict the anti-atherosclerotic mechanisms. An invitro cell model was used to explore the effect of GA on macrophage polarization and the possible mechanism involved in bone marrow dereived macrophages (BMDMs) and RAW264.7 cells stimulated with lipopolysaccharide or oxidized low-density lipoprotein. RESULTS: It was found that GA at 5 and 25 mg/kg/d significantly inhibited the development of AS and increased plaque stability, as evidenced by decreased plaque in the aorta, reduced necrotic core size and increased collagen/lipid ratio in lesions. GA reduced the proportion of M1 macrophages in plaques, but had no effect on M2 macrophages. In vitro experiments showed that GA (1, 5, 25 µg/mL) significantly decreased the proportion of CD86+ macrophages and the mRNA levels of IL-6, IL-1ß, and MCP-1 in macrophages. Experimental results showed that GA inhibited M1 macrophage polarization by regulating TLR4/MyD88/NF-κB signaling pathway. CONCLUSIONS: This study demonstrated that GA play an important role in plaque stability and macrophage polarization. GA exert the anti-atherosclerotic effect partly by regulating TLR4/MyD88/NF-κB signaling pathways to inhibit M1 polarization of macrophages. Our study provides theoretical basis and experimental data for the pharmacological activity and mechanisms of GA against AS.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Ratones , Animales , FN-kappa B/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/farmacología , Receptor Toll-Like 4/metabolismo , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/prevención & control , Aterosclerosis/genética , Placa Aterosclerótica/metabolismo , Transducción de Señal , Macrófagos/metabolismo , Lípidos
2.
Altern Ther Health Med ; 29(8): 134-138, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37535919

RESUMEN

Objective: To analyze the effect of C7-T1 extensional posterior transpedicular vertebral osteotomy (PSO) on mobility and quality of life in patients with ankylosing spondylitis (AS) and lumbar kyphosis. Methods: This study was conducted from February 2019 to February 2021 and a total of 38 patients with AS combined with kyphosis from Tianjin Union Medical Center, Tianjin, China, were selected for the study. After performing all preoperative examinations, all patients were treated with C7-T1 extensional posterior PSO osteotomy. The patients' operation and follow-up, pain degree as a Visual analogue scale (VAS) score and sagittal balance index changes before and after surgery, spinal function measured as; Bath Ankylosing Spondylitis Functional Index (BASFI) score and quality of life by Scoliosis Research Society-22 (SRS-22) score, were observed before and after surgery. Pearson correlation coefficient was used to analyze the correlation between patients' quality of life and BASFI score. Results: After surgery, the pain of the patients' back was significantly relieved, the patients' appearance and trunk balance function were significantly improved, and the symptoms related to nerve function were not significantly aggravated. No complications such as infection, internal fixation failure or spinal decompensation occurred in all patients. VAS score, kyphosis Cobb Angle and Sagittal Vertical Axis (SVA) of all patients showed P < .05 before and 1 year after surgery. BASFI score 1 year after surgery decreased significantly than that before surgery (P < .05). 1 year after surgery, body function, pain symptoms, self-image and psychological state of the patients were significantly improved, and the SRS-22 total score of the patients 1 year after surgery increased significantly than before surgery (P < 0.05). BASFI score was negatively correlated with SRS-22 score by Pearson correlation coefficient analysis (P < .05). Conclusion: C7-T1 extensional posterior PSO osteotomy has a good effect in the treatment of AS patients with lumbar kyphosis. The sagittal balance was well-restored with improvement in patients' quality of life after surgery, which makes C7-T1 osteotomy worthy of clinical application to treat patients suffering from AS combined with lumbar kyphosis.


Asunto(s)
Cifosis , Escoliosis , Espondilitis Anquilosante , Humanos , Escoliosis/complicaciones , Escoliosis/cirugía , Espondilitis Anquilosante/complicaciones , Espondilitis Anquilosante/cirugía , Calidad de Vida , Resultado del Tratamiento , Cifosis/cirugía , Cifosis/complicaciones , Osteotomía/efectos adversos , Osteotomía/métodos , Dolor , Estudios Retrospectivos
3.
ACS Biomater Sci Eng ; 9(3): 1437-1449, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36795746

RESUMEN

In the tumor microenvironment (TME), the extracellular matrix (ECM) produced by cancer-associated fibroblasts (CAFs) forms a dense barrier that prevents nanodrugs from penetrating into deep tumor sites, leading to unsatisfactory therapeutic effects. Recently, it has been found that ECM depletion and using small-sized nanoparticles are effective strategies. Herein, we reported a detachable dual-targeting nanoparticle (HA-DOX@GNPs-Met@HFn) based on reducing ECM for enhancing penetration. When these nanoparticles reached the tumor site, the nanoparticles were divided into two parts in response to matrix metalloproteinase-2 overexpressed in TME, causing a decrease in the nanoparticle size from about 124 to 36 nm. One part was Met@HFn, which was detached from the surface of gelatin nanoparticles (GNPs), which effectively targeted tumor cells and released metformin (Met) under acidic conditions. Then, Met downregulated the expression of the transforming growth factor ß by the adenosine monophosphate-activated protein kinase pathway to inhibit the activity of CAFs, thereby suppressing the production of ECM including α-smooth muscle actin and collagen I. The other was the small-sized hyaluronic acid-modified doxorubicin prodrug with autonomous targeting ability, which was gradually released from GNPs and internalized into deeper tumor cells. Intracellular hyaluronidases triggered the release of doxorubicin (DOX), which killed tumor cells by inhibiting DNA synthesis. The combination of size transformation and ECM depletion enhanced the penetration and accumulation of DOX in solid tumors. Therefore, the tumor chemotherapy effect was greatly improved.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Doxorrubicina/farmacología , Neoplasias/tratamiento farmacológico , Matriz Extracelular/metabolismo , Gelatina , Microambiente Tumoral
4.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-971273

RESUMEN

OBJECTIVE@#To evaluate the changes of periodontal phenotype (width of keratinized gingiva, thickness and height of alveolar bone) of lower anterior teeth in patients with skeletal class Ⅲ malocclusion before and after the periodontal-orthodontic-orthognathic combined treatment.@*METHODS@#In the study, 20 patients with skeletal class Ⅲ malocclusion (6 males and 14 females) completed the periodontal-orthodontic-orthognathic combined treatment were included from March 2017 to June 2022, with 39 central incisors, 40 lateral incisors and 40 canines. The mean age was (25.40±4.27) years (20-34 years). The mean follow-up time was (3.70±1.05) years from the beginning of periodontal corticotomy regenerative surgery (PCRS) to the end of the combined treatment. Cone-beam computed tomography (CBCT) was used to measure the thickness, area and height of alveolar bone by the same researcher, taken before the PCRS (T0), 6 months after the PCRS (T1), 12 months after the PCRS (T2), before the orthognathic surgery (T3), and after the periodontal-orthodontic-orthognathic combined treatment (T4). The periodontal clinical parameters were used to evaluate changes in the soft tissue by another researcher, measured before the PCRS (T0) and after the combined treatment (T4). Changes of soft and hard tissue were evaluated by the periodontal phenotype.@*RESULTS@#The width of keratinized gingiva increased significantly (all P < 0.001) in lower anterior teeth, the central incisors, lateral incisors and canines increased by (1.82±1.57) mm, (2.03±1.48) mm and (2.05±1.27) mm, respectively. The proportion of thick periodontal biotype in the central and lateral incisors increased significantly (all P < 0.001), while the changes of periodontal biotypes in the lower canines were not obvious. The thickness of labial alveolar bone of lower anterior teeth all increased significantly after periodontal corticotomy regenerative surgery and the combined treatment (all P < 0.001). The area of labial alveolar bone of lower anterior teeth also increased significantly after the combined treatment (all P < 0.001). The whole area of labial and lingual alveolar bone of central and lateral incisors increased (P < 0.001), while the whole area of canines remained the same. All The height of the alveolar bone increased (all P < 0.001) on the labial side after the treatment.@*CONCLUSION@#The periodontal phenotypes of lower anterior teeth were significantly improved after the periodontal-orthodontic-orthognathic combined treatment in patients with skeletal Angle class Ⅲ malocclusion. The improvement was long-termly stable, and the periodontal risk was reduced.


Asunto(s)
Masculino , Femenino , Humanos , Maloclusión de Angle Clase III/cirugía , Procedimientos Quirúrgicos Orales , Incisivo , Tomografía Computarizada de Haz Cónico/métodos
5.
ACS Biomater Sci Eng ; 8(10): 4413-4427, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36166484

RESUMEN

Breast cancer treatment has been challenging all the time because cancer cells have multiple signaling pathways; so, breast cancer still remains a threat to the lives and health of many patients. While common single drug therapies inhibit only one pathway, the combination of multiple mechanisms offers the potential to simultaneously suppress multiple targets and pathways to kill cancer cells more effectively. It is reported that autophagy caused by autophagy inducers and apoptosis caused by some chemotherapeutic drugs can promote ferroptosis to some extent; herein, we combined these three pathways and constructed a multifunctional dual-responsive release nanosystem of Rap@mFe3O4-DOX-HA that achieved the ferroptosis-autophagy-apoptosis synergistic effect for cancer treatment. Mesoporous Fe3O4 (mFe3O4) was set as the carrier and can also release Fe ions for ferroptosis, the autophagy inducer rapamycin (Rap) was wrapped in the carrier to trigger autophagy, and the chemotherapeutic drug doxorubicin (DOX) was used as the apoptosis inducer. At the tumor site, the prepared Rap@mFe3O4-DOX-HA nanoparticles split and released DOX/Rap in response to H+/GSH. From in vivo and in vitro studies, it was found that Rap@mFe3O4-DOX-HA nanoparticles effectively inhibited the migration of 4T1 cells, furthermore, they struck cancer cells through multiple pathways and greatly improved the anti-tumor effect. Therefore, the strategy of multi-mechanism combination achieved a therapeutic effect of 1 + 1 > 2.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/farmacología , Femenino , Humanos , Nanopartículas/uso terapéutico , Sirolimus/farmacología , Sirolimus/uso terapéutico
6.
Biomater Sci ; 10(14): 4008-4022, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35726640

RESUMEN

Although tumor starvation therapy has been proven to be an excellent method for tumor therapy, its efficiency may be weakened by autophagy, a self-protection mechanism exerted by tumors under starvation stress. Interestingly, over-activated autophagy not only improves the efficacy of starvation therapy, but also induces autophagic death. Herein, we report cascade nanozymes for enhanced starvation therapy by inducing over-activated autophagy. First, glucose oxidase (GOx) modified metal-organic frameworks (NH2-MIL88, MOF) were constructed (MOF-GOx). After loading with curcumin (Cur), Cur@MOF-GOx was further decorated with tumor-targeting hyaluronic acid (HA) to obtain Cur@MOF-GOx/HA nanozymes. GOx can catalyze glucose into H2O2 and gluconic acid, which not only leads to tumor starvation, but also provides reactants for the Fenton reaction mediated by the MOF to generate hydroxyl radicals (˙OH) for chemo-dynamic therapy. Most importantly, protective autophagy caused by tumor starvation can be over-activated by Cur to convert autophagy from pro-survival to pro-death, realizing augmented anticancer therapy efficacy. With these cascade reactions, the synergistic action of starvation, autophagy and chemo-dynamic therapy was realized. Generally, the introduction of Cur@MOF-GOx/HA into tumor cells leads to a "butterfly effect", which induces enhanced starvation therapy through subsequent autophagic cell death to completely break the self-protective mechanism of cancer cells, and generate ˙OH for chemo-dynamic therapy. Precise design allows for the use of cascade nanozymes to realize efficient cancer treatment and restrain metastasis.


Asunto(s)
Estructuras Metalorgánicas , Neoplasias , Autofagia , Línea Celular Tumoral , Glucosa Oxidasa/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Estructuras Metalorgánicas/metabolismo , Estructuras Metalorgánicas/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/patología
7.
J Biol Inorg Chem ; 27(3): 283-295, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35190875

RESUMEN

In search of new super-bacterial inhibitor agents, the recognition and binding mechanism of the B1 subclass MßL CcrA from Bacteroides fragilis with cefotaxime (CTX) and ceftazidime (CAZ) were studied using spectroscopy analysis and molecular docking. The results showed that the fluorescence quenching of CcrA induced by CTX and CAZ were all due to the complex formation, which belonged to static quenching and was forced by hydrogen bonds and Van der Waals forces, despite the greater binding ability of CTX with CcrA than CAZ. Upon recognizing CTX or CAZ, the CcrA opened its binding pocket by the microenvironmental and conformational of three loops changing to promote an induced-fit of the freshly introduced antibiotics. In addition, the whole antibiotic molecule ultimately entered the active pocket of CcrA with its original carbonate replaced by the carboxyl oxygen of the hexatomic ring adjacent to the ß-lactam ring in CTX or CAZ, forming a new tetrahedral coordination structure at the Zn2 site. Moreover, the difference in steric hindrance and electrostatic effects of the side chain affected the binding ability of the two antibiotics to the CcrA. This work showed the refined procedures of the antibiotics binding to CcrA and might provide useful information hint for the new strategy of developing the novel and innovative super-bacterial antibiotics.


Asunto(s)
Cefotaxima , Ceftazidima , Antibacterianos/farmacología , Bacteroides fragilis/metabolismo , Cefotaxima/farmacología , Ceftazidima/farmacología , Simulación del Acoplamiento Molecular , beta-Lactamasas/metabolismo
8.
Int J Neurosci ; 131(1): 1-6, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32075480

RESUMEN

Objective: The aim of this study was to assess the significance of how the degree of injury of the facet joint affects clinical outcomes in foraminoplasty.Methods: We retrospectively enrolled 64 patients treated with percutaneous endoscopic transforaminal discectomy with foraminoplasty (PETDF) from January of 2015 to December of 2016. The patients were divided into two groups depending on whether the articular surface of the facet joint was damaged. Preoperative, perioperative, demographic data, and radiographic parameters for these two groups were extracted and compared.Results: There were no significant differences between the two groups in terms of the duration of operation (p = 0.331), intraoperative blood loss volume (p = 0.631), the weight of disc (p = 0.274) or cut bone (p = 0.526). There were no significant differences between the two groups for VAS or ODI at the same time point (p > 0.05). There were significant differences in the VAS scores of low-back pain at 24 h and 24 months after surgery in the injured group. There were significant differences in ISH, ISA, rate of lumbar instability, recurrent herniation, and Macnab scores between the two groups at 24 months after surgery (p < 0.05). The regression equation between ISA and ISH was Y = 4.237 + 0.565x (where Y denotes an increase of ISA; X, reduction of ISH; F = 6.219, p = 0.015). The Poisson ratio was 0.363 (p = 0.003).Conclusions: PETDF is effective and safe for the treatment of lumbar disc herniation. However, when foraminoplasty destroys the articular surface of the facet joint, there may be increases in lumbar instability and recurrence rate post-operation.


Asunto(s)
Discectomía Percutánea/métodos , Endoscopía/métodos , Degeneración del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Vértebras Lumbares/cirugía , Canal Medular/cirugía , Adulto , Anciano , Discectomía Percutánea/tendencias , Endoscopía/tendencias , Femenino , Estudios de Seguimiento , Humanos , Degeneración del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Canal Medular/diagnóstico por imagen , Resultado del Tratamiento
9.
J Coll Physicians Surg Pak ; 29(10): 1003-1005, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31564279

RESUMEN

Pure spinal epidural cavernous hemangioma with contralateral symptoms is rarely reported. It will be very difficult to diagnose when it is complicated by contralateral symptoms. A 56-year female presented with pure lumbar epidural cavernous hemangioma with contralateral symptoms. Physical examination and imaging including X-ray, CT and MRI, suggested that it is a hemangioma complicated by spondylolisthesis. Laminectomy and exploration was performed. Postoperative X-ray showed satisfactory interbody fusion and reduction of spondylolisthesis. The patient was fully recovered four months postoperatively. Histopathological examination showed that the mass was epidural cavernous hemangioma.


Asunto(s)
Neoplasias Epidurales/complicaciones , Neoplasias Epidurales/diagnóstico por imagen , Hemangioma Cavernoso del Sistema Nervioso Central/complicaciones , Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico por imagen , Espondilolistesis/complicaciones , Espondilolistesis/diagnóstico por imagen , Neoplasias Epidurales/cirugía , Femenino , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Humanos , Laminectomía , Persona de Mediana Edad , Fusión Vertebral , Espondilolistesis/cirugía
10.
J Int Med Res ; 47(3): 1146-1153, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30632428

RESUMEN

OBJECTIVE: This study aimed to compare intraoperative lower back pain and leg pain, surgical time, and intraoperative X-ray dose in patients offered local infiltration anesthesia or continuous epidural anesthesia for transforaminal endoscopic spine system (TESSYS) surgery. METHODS: A total of 98 patients who received TESSYS treatment for single-segmental lumbar disc herniation were included, and were randomly divided into two groups: group A (49 cases; local infiltration anesthesia) and group B (49 cases; continuous epidural anesthesia). Surgical duration, intraoperative X-ray dose, and visual analog scale (VAS) scores of lower back pain and leg pain before surgery, during surgery, and 48 h after surgery were recorded and compared. RESULTS: After surgery, the VAS scores of both lower back pain and leg pain decreased in group A, and similar findings were found in group B. Group B had a shorter surgical duration, lower intraoperative X-ray dose, and lower intraoperative VAS scores of lower back pain and leg pain compared with group A. CONCLUSION: Compared with local infiltration anesthesia, continuous epidural anesthesia was more effective for pain relief during TESSYS for single-segmental lumbar disc herniation, and also contributed to a shorter surgical duration and lower X-ray exposure.


Asunto(s)
Anestesia Epidural/métodos , Endoscopía/métodos , Degeneración del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Dolor de la Región Lumbar/prevención & control , Vértebras Lumbares/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Estudios Prospectivos
11.
J Orthop Surg Res ; 13(1): 90, 2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29669576

RESUMEN

BACKGROUND: The distribution and related factors of Modic changes (MC) in the lumbar spine has been evaluated. In the present study, the MC in the cervical endplate of patients with cervical spondylotic myelopathy (CSM) was investigated. METHODS: A total of 6422 cervical endplates of 539 patients suffered from CSM (259 males and 280 females) with mean age of 46 ± 5.2 years. All patients underwent MRI scans and X-ray for evaluating the distribution of MC. The clinical information were recorded. RESULTS: It was observed that 13.0% of patients and 2.4% of endplates showed MC. There were 3.7, 7.6, and 1.7% of cases diagnosed as types I, II, and III, respectively, suggesting MC were corrected with disc degeneration. The incidence rates of MC were 0, 0.3, 0.6, 0.9, 0.7, and 0.2%, respectively, in different intervertebral disc segments C2-3, C3-4, C4-5, C5-6, C6-7, and C7T1. Disc degeneration, segment, disease course, and age were statistically related to the MC. Patients over the age of 40 more easily suffered from MC. CONCLUSIONS: MCs manifested as type II mainly in patients with CSM. The incidence was highest in the C5-6 segment. Disc degeneration greatly contributed to the occurrence of MC.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Degeneración del Disco Intervertebral/diagnóstico por imagen , Imagen por Resonancia Magnética/tendencias , Espondilosis/diagnóstico por imagen , Adulto , Femenino , Humanos , Degeneración del Disco Intervertebral/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/epidemiología , Espondilosis/epidemiología
12.
J Chromatogr A ; 1495: 31-45, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28342583

RESUMEN

Voltage dependent anion channel isoform 1 (VDAC-1) serves as an attractive target of anti-cancer drugs by mediating the entry and exit of metabolites between cytoplasm and mitochondria. This work reports on the preparation of a VDAC-1-based bioaffinity chromatographic stationary phase by linking the protein on lecithin modified microspheres. An assay of chromatographic methods including frontal analysis, zonal elution, injection dependent analysis and nonlinear chromatography were utilized to investigate the bindings of ATP, NADH and NADPH to VDAC-1. Electrostatic interactions were found to be main forces during these bindings. The calculated association constants of the three ligands to VDAC-1 showed good agreements between diverse chromatographic methods. Validated application of the stationary phase was performed by screening anti-cancer compounds of Rheum officinale Baill. using high performance affinity chromatography coupled with electrospray ionization-quadrupole time of flight mass spectrometry. Chrysophanol, emodin, rhein, aloe-emodin and catechin were identified as the bioactive components of the herb. These compounds targeted VDAC-1 through Thr207 and the N-terminal region of the protein. Taken together, the current stationary phase was possible to become a promising tool for protein-ligand interaction analysis and anti-cancer drug screening from complex matrices.


Asunto(s)
Antineoplásicos Fitogénicos/química , Ligandos , Canal Aniónico 1 Dependiente del Voltaje/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/metabolismo , Sitios de Unión , Catequina/química , Catequina/aislamiento & purificación , Catequina/metabolismo , Cromatografía de Afinidad , Emodina/química , Emodina/aislamiento & purificación , Emodina/metabolismo , Humanos , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/metabolismo , Medicina Tradicional , Simulación del Acoplamiento Molecular , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Rheum/química , Rheum/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Termodinámica , Canal Aniónico 1 Dependiente del Voltaje/metabolismo
13.
Luminescence ; 32(6): 932-941, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28185399

RESUMEN

The molecular recognition and binding interaction of beta-lactamase II from Bacillus cereus (Bc II) with penicillin V (PV) and sulbactam (Sul) at 277 K were studied by spectroscopic analysis and molecular docking. The results showed that a non-fluorescence static complex was separately formed between Bc II and two ligands, the molecular ratio of Bc II to PV or Sul was both 1:1 in the binding and the binding constants were 2.00 × 106 and 3.98 × 105 (L/mol), respectively. The negative free energy changes and apparent activation energies indicated that both the binding processes were spontaneous. Molecular docking showed that in the binding process, the whole Sul molecule entered into the binding pocket of Bc II while only part of the whole PV molecule entered into the pocket due to a long side chain, and electrostatic interactions were the major contribution to the binding processes. In addition, a weak conformational change of Bc II was also observed in the molecular recognition and binding process of Bc II with PV or Sul. This study may provide some valuable information for exploring the recognition and binding of proteins with ligands in the binding process and for the design of novel super-antibiotics.


Asunto(s)
Antibacterianos/química , Bacillus cereus/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Cefalosporinasa/química , Cefalosporinasa/metabolismo , Penicilina V/química , Sulbactam/química , Antibacterianos/metabolismo , Bacillus cereus/química , Bacillus cereus/genética , Proteínas Bacterianas/genética , Cefalosporinasa/genética , Simulación del Acoplamiento Molecular , Penicilina V/metabolismo , Análisis Espectral , Sulbactam/metabolismo
14.
J Pharm Biomed Anal ; 138: 206-214, 2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28219797

RESUMEN

The molecular recognition and interaction of beta-lactamase II from Bacillus cereus (Bc II) with penicillin V (PV) and sulbactam (Sul) especially conformational changes of Bc II in the binding process were studied through spectroscopy analysis in combination with molecular dynamics (MD) simulation. The results show that in the binding process, a new coordination bond is observed between the Zn2 of Bc II and the carboxyl-O of PV or Sul by replacing His204. Electrostatic interaction between Zn2 and the ligand provide main driving force for the binding affinity. Compared with apo Bc II, there are mainly four loops showing significant conformational changes in ligand-bound Bc II. A weak conformational transformation from ß-sheets to random coils is observed in the loop2 of ligand-bound Bc II. The conformational transformation may depend on the functional group and binding pose of the ligand, giving the binding pocket greater flexibility and accordingly allowing for an induced fit of the enzyme-ligand binding site around the newly introduced ligand. The change in the loop2 of ligand-bound Bc II may lead to the opening of the binding pocket of Bc II. Therefore, loop2 can be considered a gate for control of ligand access in Bc II, hence its dynamic response should be considered in new drug design and development.


Asunto(s)
Bacillus cereus/metabolismo , Cefalosporinasa/metabolismo , Penicilina V/metabolismo , Sulbactam/metabolismo , Sitios de Unión/fisiología , Simulación de Dinámica Molecular , Unión Proteica/fisiología , Conformación Proteica en Lámina beta , Análisis Espectral/métodos , Electricidad Estática
15.
Asian Pac J Cancer Prev ; 15(11): 4377-84, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24969857

RESUMEN

According to the World Health Organization (WHO), 1.37 million people died of lung cancer all around the world in 2008, occupying the first place in all cancer-related deaths. However, this number might be decreased if patients were detected earlier and treated appropriately. Unfortunately, traditional imaging techniques are not sufficiently satisfactory for early detection of lung cancer because of limitations. As one alternative, breath volatile organic compounds (VOCs) may reflect the biochemical status of the body and provide clues to some diseases including lung cancer at early stage. Early detection of lung cancer based on breath analysis is becoming more and more valued because it is non-invasive, sensitive, inexpensive and simple. In this review article, we analyze the limitations of traditional imaging techniques in the early detection of lung cancer, illustrate possible mechanisms of the production of VOCs in cancerous cells, present evidence that supports the detection of such disease using breath analysis, and summarize the advances in the study of E-noses based on gas sensitive sensors. In conclusion, the analysis of breath VOCs is a better choice for the early detection of lung cancer compared to imaging techniques. We recommend a more comprehensive technique that integrates the analysis of VOCs and non-VOCs in breath. In addition, VOCs in urine may also be a trend in research on the early detection of lung cancer.


Asunto(s)
Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Compuestos Orgánicos Volátiles , Técnicas Biosensibles/métodos , Pruebas Respiratorias/métodos , Diagnóstico por Imagen/métodos , Nariz Electrónica , Humanos , Neoplasias Pulmonares/orina , Compuestos Orgánicos Volátiles/orina
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