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1.
Acta Biomater ; 167: 534-550, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37302734

RESUMO

Currently, the treatment of triple-negative breast cancer (TNBC) is limited by the special pathological characteristics of this disease. In recent years, photodynamic therapy (PDT) has created new hope for the treatment of TNBC. Moreover, PDT can induce immunogenic cell death (ICD) and improve tumor immunogenicity. However, even though PDT can improve the immunogenicity of TNBC, the inhibitory immune microenvironment of TNBC still weakens the antitumor immune response. Therefore, we used the neutral sphingomyelinase inhibitor GW4869 to inhibit the secretion of small extracellular vesicles (sEVs) by TNBC cells to improve the tumor immune microenvironment and enhance antitumor immunity. In addition, bone mesenchymal stem cell (BMSC)-derived sEVs have good biological safety and a strong drug loading capacity, which can effectively improve the efficiency of drug delivery. In this study, we first obtained primary BMSCs and sEVs, and then the photosensitizers Ce6 and GW4869 were loaded into the sEVs by electroporation to produce immunomodulatory photosensitive nanovesicles (Ce6-GW4869/sEVs). When administered to TNBC cells or orthotopic TNBC models, these photosensitive sEVs could specifically target TNBC and improve the tumor immune microenvironment. Moreover, PDT combined with GW4869-based therapy showed a potent synergistic antitumor effect mediated by direct killing of TNBC and activation of antitumor immunity. Here, we designed photosensitive sEVs that could target TNBC and regulate the tumor immune microenvironment, providing a potential approach for improving the effectiveness of TNBC treatment. STATEMENT OF SIGNIFICANCE: We designed an immunomodulatory photosensitive nanovesicle (Ce6-GW4869/sEVs) with the photosensitizer Ce6 to achieve photodynamic therapy and the neutral sphingomyelinase inhibitor GW4869 to inhibit the secretion of small extracellular vesicles (sEVs) by triple-negative breast cancer (TNBC) cells to improve the tumor immune microenvironment and enhance antitumor immunity. In this study, the immunomodulatory photosensitive nanovesicle could target TNBC cells and regulate the tumor immune microenvironment, thus providing a potential approach for improving the treatment effect in TNBC. We found that the reduction in tumor sEVs secretion induced by GW4869 improved the tumor-suppressive immune microenvironment. Moreover, similar therapeutic strategies can also be applied in other kinds of tumors, especially immunosuppressive tumors, which is of great value for the clinical translation of tumor immunotherapy.


Assuntos
Vesículas Extracelulares , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Esfingomielina Fosfodiesterase , Compostos de Anilina , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Esterases , Microambiente Tumoral , Linhagem Celular Tumoral
2.
BMC Musculoskelet Disord ; 24(1): 350, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147608

RESUMO

OBJECTIVE: To design a cross-inverted triangular pattern to insert compression screw nails for the treatment of femoral neck fractures and to compare the biomechanics of inserting compression screw nails in cross-inverted triangular patterns and inverted triangular patterns. I am very sorry that a corresponding author needs to be added to the article. I do not know how to insert it, so I make a note here. Please check the attachment I uploaded. METHODS: The reasonableness of the model is first analyzed using finite elements. A total of 6 adult human specimens were selected, of which 3 males and 3 females were divided into the A1, B1, and C1 groups and the A2, B2, and C2 groups by the random number table method. The A1 and A2 groups were made into subhead femoral neck fracture models, the B1 and B2 groups were made into trans-neck femoral neck fracture models, and the C1 and C2 groups were made into basal femoral neck fracture models. The right femur of each group had a compression screw nail inserted in the crossed-inverted triangular pattern, and the left femur of each group had a compression screw nail inserted in the inverted triangular pattern. The static compression test was performed by an electronic universal testing machine. The maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head were read according to the pressure-displacement curve drawn in the experiment. RESULTS: The finite element analysis showed that the cross-inverted triangular hollow threaded nail has better conductivity and more stable fixation than the inverted triangular hollow threaded nail. The maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head of the left femur were greater than those of the right femur in the A1, A2, B1, B2 and C2 groups, while the maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head of the left femur were smaller than those of the right femur in the C1 group. There was no statistically significant difference in the maximum load of the femoral neck or the load of 3.00 mm axial displacement of the femoral head between the A1 and A2 groups, the B1 and B2 groups, or the C1 and C2 groups (P > 0.05). After the K-S test, the maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head were normally distributed (P = 0.20), and the LSD-t test was conducted for the two load data; the difference was not statistically significant (P = 0.235). CONCLUSION: The effect of compression screw nails in the cross-inverted triangular pattern was the same in males and females, and stability was better in the fixation of subhead and trans-neck femoral neck fractures. However, its stability in fixation of basal femoral neck fracture is worse than that of the inverted triangular pattern. The cross-inverted triangular hollow threaded nail has better conductivity and more stable fixation than the inverted triangular hollow threaded nail.


Assuntos
Fraturas do Fêmur , Fraturas do Colo Femoral , Adulto , Humanos , Unhas , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas do Colo Femoral/cirurgia , Fêmur/cirurgia , Fenômenos Biomecânicos , Análise de Elementos Finitos , Fraturas do Fêmur/cirurgia
3.
Exp Ther Med ; 25(1): 17, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36545273

RESUMO

Pacemaker implantation is becoming increasingly common in patients with breast cancer. Comprehensive treatment options, such as surgery, chemotherapy, radiation therapy, targeted therapy and immunotherapy, have greatly improved the prognosis of patients with breast cancer. In particular, radiotherapy is an important means of comprehensive breast cancer treatment that can reduce recurrence and prolong survival in high-risk patients who underwent mastectomy. The pacemaker electrical pulse generator is typically implanted subcutaneously in the left subclavian area above the pectoral muscle through the subclavian vein. The present report implemented a new method of 'temporary pacemaker electrode and permanent artificial pacemaker placement' through the right axillary vein in a patient with breast cancer. An electrical pulse generator was placed in the right subcutaneous subclavian tissue. The pacemaker was placed under the right clavicle, and the pacemaker was included as organ at risk (OAR). Dose of planning organ at risk volume (PRV) with additional 6 mm margin to the pacemaker was limited during radiotherapy planning design. This patient with breast cancer, who was also complicated with other underlying comorbidities (such as atrial fibrillation, coronary atherosclerosis, cardiac insufficiency, hypertension, type 2 diabetes mellitus) and implanted with a cardiac pacemaker, was treated with safe (means that the patient has not developed heart disease because of the pacemaker problem) and effective (tumor can be effectively controlled under the condition that the pacemaker does not malfunction) radiotherapy. At present, the patient has successfully completed radiation therapy for breast cancer with no recurrence or metastasis. To the best of our knowledge, the present report is the first to document this application, demonstrating the treatment of a patient with breast cancer and cardiac pacemaker implantation, which is worthy of further study and continuous improvement in clinical practice.

4.
Front Immunol ; 13: 953334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36300123

RESUMO

Background: Postpartum hemorrhage (PPH) is one of the leading causes of maternal mortality. Promptly recovering blood loss is critical for PPH. Intraoperative cell salvage (ICS) is a method to collect and process red blood cells (RBCs) from the blood lost during surgery and transfuse them to the patient's circulation during or immediately after surgery. Its effectiveness in reducing the demand for allogeneic blood transfusion has been proven, but its effectiveness and safety as a sole treatment for PPH during Cesarean sections are unclear. This is particularly important for patients who cannot or do not want to accept allogeneic blood transfusion. Materials and methods: In this prospective randomized controlled study, patients with high risks of PPH were randomized into the ICS group or the control group, receiving ICS or allogeneic RBC transfusion if their hemoglobin level was less than 80 g/L during operation. Data collected include clinical examination, blood cell count, hemoglobin level, coagulation function, and plasma levels of fetal hemoglobin, tissue factor, and alpha-fetoprotein before and after fetal delivery and 0, 2, and 12 h after treatment. Adverse events were recorded. Results: A total of 130 patients were enrolled, aged 33 ± 1 years with a mean gestation period of 37 ± 1 week. The most common cause of Cesarean section was placenta previa, followed by twin pregnancy, scarred uterus, preeclampsia, placental abruption, fetal distress, and placenta accreta spectrum. Bleeding amount was similar between the two groups. The ICS group, compared to controls, had more efficient increases in levels of hemoglobin, RBC, and hematocrit (all p < 0.05). Coagulation function was maintained in the ICS group but reduced in controls 24 h after transfusion, indicated by significantly reduced fibrinogen level and prolonged prothrombin time (PT), thrombin time (TT), and activated partial thromboplastin time (aPTT) (all p < 0.05). There was a transient but significant decrease in plasma tissue factor and alpha-fetoprotein levels and an increase in plasma fetal hemoglobin level with ICS treatment in the postpartum period. No adverse event occurred with ICS intervention. Conclusion: ICS is an effective and safe intervention for patients with a high risk of PPH during elective or emergency Cesarean section. It can effectively clear tissue factors and alpha-fetoprotein but not fetal hemoglobin.


Assuntos
Hemorragia Pós-Parto , Humanos , Feminino , Gravidez , Hemorragia Pós-Parto/terapia , alfa-Fetoproteínas , Cesárea/efeitos adversos , Cesárea/métodos , Estudos Prospectivos , Tromboplastina , Placenta , Hemoglobinas/análise , Fibrinogênio
5.
Lifetime Data Anal ; 27(2): 300-332, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33417074

RESUMO

This paper considers the optimal design for the frailty model with discrete-time survival endpoints in longitudinal studies. We introduce the random effects into the discrete hazard models to account for the heterogeneity between experimental subjects, which causes the observations of the same subject at the sequential time points being correlated. We propose a general design method to collect the survival endpoints as inexpensively and efficiently as possible. A cost-based generalized D ([Formula: see text])-optimal design criterion is proposed to derive the optimal designs for estimating the fixed effects with cost constraint. Different computation strategies based on grid search or particle swarm optimization (PSO) algorithm are provided to obtain generalized D ([Formula: see text])-optimal designs. The equivalence theorem for the cost-based D ([Formula: see text])-optimal design criterion is given to verify the optimality of the designs. Our numerical results indicate that the presence of the random effects has a great influence on the optimal designs. Some useful suggestions are also put forward for future designing longitudinal studies.


Assuntos
Algoritmos , Projetos de Pesquisa , Humanos , Estudos Longitudinais
6.
Dalton Trans ; 49(9): 2850-2861, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32067026

RESUMO

A family of new dinuclear lanthanide complexes as the simplest entities showing intramolecular magnetic interactions, [Ln2(dbm)2(L)2(CH3OH)2] (Ln = Tb (1), Dy (2), Ho (3), Er (4), Yb (5), Lu (6)), [Ln2(acac)2(L)2(EtOH)2] (Ln = Dy (7), Er (8)), [Dy2(TTA)2(L)2(CH3OH)2]·2CH2Cl2 (9) and [Dy2(tfa)2(L)2(CH3OH)2] (10) (H2L = N'-(2-hydroxy-5-methylphenyl)-pyrazine-2-carbohydrazide, Hdbm = 1,3-diphenyl-1,3-propanedione, Hacac = acetylacetone, HTTA = 2-thenoyltrifluoroacetone, Htfa = trifluoroacetylacetone), were constructed successfully by the reaction of a Schiff base ligand H2L and four different ß-diketonate salts. As for complexes 4, 5 and 8, all exhibit the characteristic emission peaks of the corresponding Er3+, Yb3+ and Er3+ ions, respectively. Meanwhile, the excitation wavelength (510 nm) of 5 is located in the visible region, confirming its significant potential application value. Magnetic studies indicate that complexes 9 and 10 exhibit characteristic slow relaxation of magnetization with the energy barriers (Ueff) of 102 K for 9 and 140 K for 10 under a zero dc field. Under the optimized dc fields, slow magnetic relaxations are present in 2 and 7, and the Ueff values of 9 and 10 have been improved. This proves that the ß-diketonate co-ligands deserve an important role in regulating Dy-SMMs influenced by the diverse perturbations of the axial crystal field originating from minor changes in the coordination environment.

7.
PDA J Pharm Sci Technol ; 72(6): 584-598, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30030349

RESUMO

Chromatography resins used for purifying biopharmaceuticals are generally dedicated to a single product. In good manufacturing practice (GMP) facilities that manufacture a limited amount of any particular product, this practice can result in the resin being used for a fraction of its useful life. A methodology for extending resin reuse to multiple products is described. With this methodology, resin and column performance, product carryover, and cleaning effectiveness are continually monitored to ensure that product quality is not affected by multiproduct resin reuse (MRR). Resin and column performance is evaluated in terms of (a) system suitability parameters, such as peak-shape and transition, and height equivalent theoretical plate (HETP) data; (b) key operating parameters, such as flow rate, inlet pressure, and pressure drop across the column; and (c) process performance parameters, such as impurity profiles, product quality, and yield. Historical data are used to establish process capability limits (PCLs) for these parameters. Operation within the PCLs provides assurance that column integrity and binding capacity of the resin are not affected by MRR.Product carryover defined as the carryover of the previously processed product (A) into a dose of the subsequently processed product (B) (COA→B), should be acceptable from a predictive patient safety standpoint. A methodology for determining COA→B from first principles and setting acceptance limits for cleaning validation is described.Cleaning effectiveness is evaluated by performing a blank elution run after inter-campaign cleaning and prior to product changeover. The acceptance limits for product carryover (COA→B) are more stringent for MRR than for single-product resin reuse. Thus, the inter-campaign cleaning process should be robust enough to consistently meet the more stringent acceptance limits for MRR. Additionally, the analytical methods should be sensitive enough to adequately quantify the concentration of the previously processed product (A) and its degradants in the eluent.General considerations for designing small-scale chromatographic studies for process development are also described. These studies typically include process-cycling runs with multiple products followed by viral clearance studies with a panel of model viruses. Small-scale studies can be used to optimize cleaning parameters, predict resin performance and product quality, and estimate the number of multiproduct purification cycles that can be run without affecting product quality. The proposed methodology is intended to be broadly applicable; however, it is acknowledged that alternative approaches may be more appropriate for specific scenarios.LAY ABSTRACT: Chromatography resins used for purifying biopharmaceuticals are generally dedicated to a single product. In good manufacturing practice (GMP) facilities that make a limited amount of any particular product, this practice can result in the resin being used for a fraction of its useful life. A methodology for extending resin reuse to multiple products is described. With this methodology, resin and column performance, product carryover, and cleaning effectiveness are continually monitored to ensure that product quality is not affected by multiproduct resin reuse.General considerations for designing small-scale chromatographic studies for process development are described. These studies typically include process-cycling runs with multiple products followed by viral clearance studies with a panel of model viruses. Small-scale studies can be used to optimize cleaning parameters, predict resin performance and product quality, and estimate the number of multiproduct purification cycles that can be run without impacting product quality.The proposed methodology is intended to be broadly applicable; however, it is acknowledged that alternative approaches may be more appropriate for specific scenarios.


Assuntos
Produtos Biológicos/normas , Cromatografia/métodos , Tecnologia Farmacêutica/métodos , Indústria Farmacêutica/métodos , Reutilização de Equipamento , Proteínas Recombinantes/normas , Vírus/isolamento & purificação
8.
J Pharm Biomed Anal ; 28(5): 953-63, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12039638

RESUMO

Staphylokinase, a bacterially-derived protein which functions as a plasminogen activator, has potential utility as a human therapeutic for thrombotic disorders. A recombinant version of this protein, SY161, contains 13 amino acid substitutions designed to decrease immunogenicity, and has been covalently modified by crosslinking a 5 kDa polyethyleneglycol (PEG) group to the N-terminal region to prolong the drug circulating half-life. The recombinant PEG-modified SY161 staphylokinase is currently in phase II clinical trials as a treatment for acute myocardial infarction. We have developed a sensitive product specific host cell protein (HCP) assay in the ELISA format to monitor in process host-derived contaminant clearance and final drug product purity. The assay is based upon use of goat polyclonal antibodies raised against E. coli host strain cell proteins from a null cell line, extracted by the same manufacturing process used to produce SY161. The identification and clearance of HCP contaminants was confirmed during drug product production using SDS-PAGE and Western blotting utilizing the same polyclonal HCP antibodies. The assay is specific for E. coli host cell strain proteins with a useful detection range from 1 to 100 ng/ml, and is not affected by product level. The level of residual HCPs in the clinical product produced by our manufacturing process was determined to be less than 1 ng/ml at a product concentration of 1 mg/ml.


Assuntos
Ativadores de Plasminogênio/análise , Proteínas/análise , Fosfatase Alcalina/análise , Animais , Western Blotting , Corantes , Contaminação de Medicamentos , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Escherichia coli/química , Cabras/imunologia , Indicadores e Reagentes , Metaloendopeptidases/análise , Mutação , Polietilenoglicóis/análise , Proteínas Recombinantes/análise , Padrões de Referência , Reprodutibilidade dos Testes
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