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1.
Front Oncol ; 14: 1334082, 2024.
Article in English | MEDLINE | ID: mdl-38410115

ABSTRACT

Objective: The aim of this study was to develop and validate a series of breast cancer-related lymphoedema risk prediction models using machine learning algorithms for early identification of high-risk individuals to reduce the incidence of postoperative breast cancer lymphoedema. Methods: This was a retrospective study conducted from January 2012 to July 2022 in a tertiary oncology hospital. Subsequent to the collection of clinical data, variables with predictive capacity for breast cancer-related lymphoedema (BCRL) were subjected to scrutiny utilizing the Least Absolute Shrinkage and Selection Operator (LASSO) technique. The entire dataset underwent a randomized partition into training and test subsets, adhering to a 7:3 distribution. Nine classification models were developed, and the model performance was evaluated based on accuracy, sensitivity, specificity, recall, precision, F-score, and area under curve (AUC) of the ROC curve. Ultimately, the selection of the optimal model hinged upon the AUC value. Grid search and 10-fold cross-validation was used to determine the best parameter setting for each algorithm. Results: A total of 670 patients were investigated, of which 469 were in the modeling group and 201 in the validation group. A total of 174 had BCRL (25.97%). The LASSO regression model screened for the 13 features most valuable in predicting BCRL. The range of each metric in the test set for the nine models was, in order: accuracy (0.75-0.84), sensitivity (0.50-0.79), specificity (0.79-0.93), recall (0.50-0.79), precision (0.51-0.70), F score (0.56-0.69), and AUC value (0.71-0.87). Overall, LR achieved the best performance in terms of accuracy (0.81), precision (0.60), sensitivity (0.79), specificity (0.82), recall (0.79), F-score (0.68), and AUC value (0.87) for predicting BCRL. Conclusion: The study established that the constructed logistic regression (LR) model exhibits a more favorable amalgamation of accuracy, sensitivity, specificity, recall, and AUC value. This configuration adeptly discerns patients who are at an elevated risk of BCRL. Consequently, this precise identification equips nurses with the means to undertake timely and tailored interventions, thus averting the onset of BCRL.

2.
BMC Cardiovasc Disord ; 23(1): 259, 2023 05 19.
Article in English | MEDLINE | ID: mdl-37208627

ABSTRACT

BACKGROUND: Post cardiac injury syndrome (PCIS) is characterized by the development of pericarditis with or without pericardial effusion due to a recent cardiac injury. The relatively low incidence makes diagnosis of PCIS after implantation of a pacemaker easily be overlooked or underestimated. This report describes one typical case of PCIS. CASE PRESENTATION: We present a case report of a 94-year-old male with a history of sick sinus syndrome managed with a dual-chamber pacemaker who presented with PCIS after two months of pacemaker implantation. He gradually developed chest discomfort, weakness, tachycardia and paroxysmal nocturnal dyspnea and cardiac tamponade after two months of pacemaker. Post-cardiac injury syndrome related to dual-chamber pacemaker implantation was considered based on exclusion of other possible causes of pericarditis. His therapy was drainage of pericardial fluid and managed with a combination of colchicine and support therapy. He was placed on long-term colchicine therapy to prevent any recurrences. CONCLUSION: This case illustrated that PCIS can occur after minor myocardial injury, and that the possibility of PCIS should be considered if there is a history of possible cardiac insult.


Subject(s)
Cardiac Tamponade , Heart Injuries , Pacemaker, Artificial , Pericardial Effusion , Pericarditis , Male , Humans , Aged, 80 and over , Pacemaker, Artificial/adverse effects , Pericarditis/diagnosis , Pericarditis/etiology , Pericarditis/therapy , Heart Injuries/diagnostic imaging , Heart Injuries/etiology , Heart Injuries/therapy , Pericardial Effusion/diagnostic imaging , Pericardial Effusion/etiology , Cardiac Tamponade/diagnostic imaging , Cardiac Tamponade/etiology , Cardiac Tamponade/therapy
3.
Sci Total Environ ; 892: 164397, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37247732

ABSTRACT

As a tree species of shelterbelts, Populus popularis maintains significant ecological functions in arid and semiarid areas. However, stand transpiration (T) and canopy conductance (gc) dynamics of P. popularis are unclear in arid irrigated areas with shallow groundwater fluctuations. To better understand the responses of T and gc to meteorological factors, soil water, and shallow groundwater in arid areas, we observed the environmental conditions and sap flow of P. popularis, and quantified T and gc in three growing seasons of 2018-2020 in a typical arid area of China. Results showed T and gc ranged from 0.18 to 6.11 mm day-1 and 2.26-12.54 mm s-1 in 2018-2020, respectively. Solar radiation and vapor pressure deficit (VPD) were major drivers of T at daily scales. It was consistently found that T exponentially decreased with increasing groundwater table depth (GTD) and decreasing reference evapotranspiration in three years. gc is primarily influenced by VPD and is positively related to soil water content in 0-30 cm soil layer (SWC0-30 cm). Moreover, low SWC0-30 cm and deepening GTD jointly decreased T and gc by 22.45 % and 30.41 %, respectively. The response of gc to VPD was susceptible to groundwater fluctuations, and the synergistic influences of VPD and GTD on gc could be well described by the logarithmic function, especially in 2019. The sensitivity of gc to VPD and its variations under different environmental conditions suggested that a flexible stomatal regulation of transpiration occurred in the observed P. popularis with the arid climate and shallow groundwater. These findings provided the essential basis for the water use strategy of P. popularis and stand water resources management in arid regions.


Subject(s)
Populus , Water , Water/physiology , Populus/physiology , Plant Transpiration/physiology , Soil , Seasons , Trees/physiology
4.
Asia Pac J Clin Oncol ; 19(4): 439-457, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36457166

ABSTRACT

Over the past decade, the number of cancer cases has continued to rise, placing a heavy burden on patients' families and healthcare systems. Although innovative treatments and drugs have improved patient outcomes, the financial toxicity (FT) of treatment is a growing concern among oncologists. Previous research have examined the impacts of FT on the HRQOL of cancer patients. However, the extent of the association is unclear, given that previous studies vary in the enrolled population, adjustment of confounding factors, and usage of FT assessment tools. To address this gap, the main purpose of this systematic review is to examine the relationship between FT and HRQOL of cancer survivors, and explore any potential factors that may affect this relationship.


Subject(s)
Cancer Survivors , Neoplasms , Humans , Quality of Life , Cost of Illness , Financial Stress , Neoplasms/therapy
5.
Cancers (Basel) ; 14(21)2022 Nov 04.
Article in English | MEDLINE | ID: mdl-36358852

ABSTRACT

(1) Background: Recently, cell division cycle associated 8 (CDCA8) was found to be overexpressed in pancreatic ductal adenocarcinoma (PDAC). Here, we aimed to explore the specific mechanism of action of CDCA8 in PDAC progression. (2) Methods: All human PDAC samples and clinical data were collected from Huashan Hospital, Fudan University. All experimental studies were carried out using many in vitro and in vivo assays, including lentiviral transfection, real-time quantitative polymerase chain reaction (qPCR), western blotting, co-immunoprecipitation (Co-IP), chromatin IP (ChIP)-qPCR, dual-luciferase reporter, and in vivo imaging assays. (3) Results: Clinical data analysis of human PDAC samples revealed that CDCA8 overexpression were positively and negatively associated with tumor grade (p = 0.007) and overall survival (p = 0.045), respectively. CDCA8 knockdown inhibited PDAC proliferation and invasion in in vitro and in vivo assays. CD44 was also up-regulated by CDCA8 during PDAC progression. CDCA8 could be combined with SNAI2 to form a CDCA8/SNAI2 complex to integrate with the CD44 promoter as indicated through ChIP-qPCR and dual-luciferase reporter assays. (4) Conclusion: We showed that CDCA8-CD44 axis plays a key role in the proliferation and invasion of PDAC, which provides a potential target for treatment.

6.
Oxid Med Cell Longev ; 2022: 3243647, 2022.
Article in English | MEDLINE | ID: mdl-36211828

ABSTRACT

Pancreatic ductal adenocarcinoma (PDA) is often concomitant with diabetes mellitus, which mainly manifests as an increased blood glucose level. Previous studies revealed that diabetic status reduced the survival and blunted gemcitabine sensitivity in PDA patients. This study is aimed at analyzing the mechanism of elevated gemcitabine resistance and cancer invasion ability under high glucose environment. We selected 129 patients with 22 surgical resected samples from 2015 to 2021, who underwent pancreatic surgery in Huashan Hospital. The gene expression and clinical data of PDA were obtained from The Cancer Genome Atlas (TCGA) website and were analyzed by R software. Cell viability assays and flow cytometry were applied to detect gemcitabine sensitivity and apoptosis levels in pancreatic cancer cells. Wound healing and Transwell tests were used to analyze the invasion and metastasis of cancer cells. Streptozotocin (STZ) was used to establish a hyperglycemic mouse model for the in vivo study. In this study, diabetic PDA gemcitabine users showed reduced survival compared to euglycemic PDA gemcitabine users. Clinical samples and laboratory studies revealed that MMP-3 expression was associated with glucose concentration and diabetic status. Elevated MMP-3 expression was positively related to cancer invasion and gemcitabine resistance in PDA cells and gemcitabine resistant PDA cells. Blocking MMP-3 expression inhibited gemcitabine resistance and cancer progression in cellular and animal models. MMP-3 was closely related to the expression of RRM1, a gemcitabine metabolism-related gene. Reactive oxygen species (ROS) level increased under higher glucose concentrations and was mediated by NOX4. ROS determined the MMP-3 expression in pancreatic cancer cells. Inhibiting NOX4 expression effectively suppressed MMP-3 expression, gemcitabine resistance, and cancer invasion. In conclusion, a high glucose environment induces gemcitabine resistance and cancer invasion via ROS/MMP-3 signaling pathway. MMP-3 can be a potential novel target for suppressing gemcitabine resistance and invasion in PDA.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Animals , Blood Glucose , Carcinoma, Pancreatic Ductal/drug therapy , Cell Line, Tumor , Deoxycytidine/analogs & derivatives , Drug Resistance, Neoplasm/genetics , Matrix Metalloproteinase 3/metabolism , Mice , Pancreatic Neoplasms/metabolism , Reactive Oxygen Species , Signal Transduction , Streptozocin , Gemcitabine , Pancreatic Neoplasms
7.
Front Surg ; 9: 890412, 2022.
Article in English | MEDLINE | ID: mdl-35656085

ABSTRACT

Purpose: Gemcitabine (GEM) is the first-line chemotherapeutic drug for pancreatic cancer treatment in clinical practice. However, many reasons can reduce the efficacy of GEM, among which the high expression of ATP-binding cassette (ABC) transporters is a significant factor. In this study, we aimed to investigate the antitumor effect of gemcitabine-loaded human serum albumin nanoparticle (GEM-HSA-NP) on GEM-resistant pancreatic cancer cells induced by the high expression of ABC transporters, namely multidrug resistance protein 1/P-gp/ABCB1 (MDR1) and multidrug resistance-associated protein 1/ ABCC1 (MRP1). Methods: MDR1 and MRP1 were stably overexpressed via lentiviral transduction in the pancreatic cancer cell lines BxPC3 and PANC1. Proliferation inhibition assays, cell cycle arrest and apoptosis analyses were conducted to examine the antitumor effect of GEM-HSA-NP. In addition, intracellular ATP levels were determined to explore the potential mechanisms implicated preliminarily. Results: When administered to GEM-resistant cancer cells, GEM-HSA-NP displayed its antitumor effect by promoting the inhibition of proliferation, cell cycle arrest, and apoptosis induction. Intracellular ATP depletion, caused by the albumin component of GEM-HSA-NP was proposed to be potentially involved in the modulation of ABC transporter activity. Conclusion: GEM-HSA-NP can effectively overcome GEM-resistance induced by MDR1 and MRP1 overexpression, which highlights its potential value in a clinical setting.

8.
Cancer Manag Res ; 14: 2091-2104, 2022.
Article in English | MEDLINE | ID: mdl-35769228

ABSTRACT

Purpose: Pancreatic cyst neoplasm (PCN) is a precursor of pancreatic cancer. Previous studies reported PCN was often concurrent with diabetes. We aim to examine the association between diabetes with PCN malignancy and to detect the potential role of diabetes in PCN management and treatment. Patients and Methods: A total of 224 patients who were diagnosed with the three major types of PCN (IPMN, MCN, and SCN) and underwent surgical resection were selected. Patients were divided into three groups (normal group, new-onset diabetes group (NODM) (<4years), and long-standing diabetes group (LSDM) (>4years)) according to diabetic history and diagnostic time interval. Diabetes, fast blood glucose level, HbA1c, and insulin resistance level were measured. Malignant PCN (mPCN) radiological features (worrisome features and high-risk stigmata) were analyzed. Pathological features (PCN type, dysplasia grade, tumor stage, and tumor volume) and immunohistology of Ki67 and SMAD4 were performed. Diagnostic efficacy of each variable was determined by the ROC curve. mPCN diagnosis was the main outcome in diagnostic prediction and overall survival as the glucose controlling outcome variables. Results: Diabetes groups (NODM and LSDM) showed difference with the normal group in age, weight loss, malignancy, CA19-9 value, CEA value, Ki-67 value, tumor volume, pathological grade, and a lowered pancreatic fistula risk. NODM was related to insulin resistance, weight loss, and SMAD4 mutation. NODM (87.3%) and high insulin resistance rate (93.6%) significantly increased the sensitivity of radiological evidence-based mPCN diagnosis. Moreover, long-standing diabetes and elevated HbA1c led to reduced survival in mPCN patients than the normal PCN group. Anti-diabetic drugs showed limited influence on PCN malignancy and tumor volume. Conclusion: NODM in PCN patients was associated with malignancy, insulin resistance, weight loss, and SMAD4 mutation. Prediabetic status and NODM diagnosis enhanced the diagnostic accuracy of radiological standards (worrisome features and high-risk stigmata). Stable glucose surveillance is necessary for mPCN patients' survival.

9.
Front Cell Dev Biol ; 10: 844028, 2022.
Article in English | MEDLINE | ID: mdl-35252207

ABSTRACT

Increased insulin level (or "hyperinsulinemia") is a common phenomenon in pancreatic ductal adenocarcinoma (PDA) patients and signals poor clinical outcomes. Insulin is safe in low PDA risk population, while insulin significantly promotes PDA risk in high PDA risk population. The correlation between insulin and PDA is a reciprocal self-reinforcing relationship. On the one hand, pancreatic cancer cells synthesize multiple molecules to cause elevated peripheral insulin resistance, thus enhancing hyperinsulinemia. On the other hand, insulin promotes pancreatic cancer initiation and sustains PDA development by eliciting tumorigenic inflammation, regulating lipid and glucose metabolic reprogram, overcoming apoptosis through the crosstalk with IGF-1, stimulating cancer metastasis, and activating tumor microenvironment formation (inflammation, fibrosis, and angiogenesis). Currently, taking glucose sensitizing agents, including metformin, SGLT-2 inhibitor, and GLP-1 agonist, is an effective way of lowering insulin levels and controlling PDA development at the same time. In the future, new drugs targeting insulin-related signal pathways may pave a novel way for suppressing PDA initiation and progression.

10.
J Clin Pharm Ther ; 47(6): 841-843, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35118681

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Allopurinol is widely used for hyperuricemia and gouty arthritis, but is associated with cutaneous adverse drug reactions (CADRs). HLA-B*58:01 is a highly specific and effective genetic marker for the detection of allopurinol-induced CADRs, especially for Asian descents. CASE SUMMARY: A 60-year-old Chinese Han male patient took allopurinol for lowering uric acid after the negative result from HLA-B*58:01 testing. Then, he experienced episodes of well-demarcated pruritic erythematous patches on the whole body that developed into blisters and pustular eruption. Fixed drug eruption (FDE) was diagnosed by skin biopsy and improved with withdrawal and hormone treatments. WHAT IS NEW AND CONCLUSION: It should be kept in mind that cutaneous drug eruption might occur after allopurinol administration in Asians of HLA-B*58:01 negative. Awareness among medical practitioners about FDE can lead to correct diagnosis, treatment and decreased damage as well as lower therapeutic costs.


Subject(s)
Drug Eruptions , Hyperuricemia , Allopurinol/adverse effects , Asian People/genetics , Drug Eruptions/diagnosis , Drug Eruptions/genetics , HLA-B Antigens/genetics , Humans , Male , Middle Aged
11.
BMC Cancer ; 22(1): 116, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35090421

ABSTRACT

BACKGROUND: Sodium glucose transporters (SGLTs) play vital roles in glucose uptake in many solid cancers, including pancreatic cancer (PC). However, their expression profile in pancreatic cancer and correlation with prognosis are not clear. Thus, we aimed to analyse the expression profile and prognostic significance of SGLT-1 and SGLT-2 in PC. METHODS: Eighty-eight patients with pancreatic ductal adenocarcinoma (PDAC) undergoing surgery in Huashan Hospital, Fudan University, from July 2017 to June 2020 were enrolled in the study. Specimens for immunohistochemistry were obtained through surgical resection. Bioinformatics analysis was performed based on the Gene Expression Omnibus (GEO), Oncomine and The Cancer Genome Atlas (TCGA) databases. The statistics were calculated using IBM SPSS Statistics, version 20 and R 4.1.1. P values lower than 0.05 were considered to indicate statistical significance. RESULTS: SGLT-1 but not SGLT-2 was significantly overexpressed in PDAC. Survival analysis showed that the median overall survival (OS) and progression-free survival (PFS) of patients with high SGLT-1 expression were significantly longer than that of patients with low SGLT-1 expression. Cox regression indicated that high SGLT-1 expression was an independent predictor for a better prognosis, while residual tumour status (R1 and R2) was an independent risk factor for a poor prognosis. Finally, PDZK1-interacting protein 1 (PDZK1IP1), a protein participating in the generation of reactive oxygen species, was overexpressed in PDAC and its expression was significantly correlated with SGLT-1. CONCLUSIONS: SGLT-1 but not SGLT-2 was overexpressed in PDAC, and the overexpression of SGLT-1 could be a predictor of a better prognosis. Residual tumour status (R1 and R2) was a risk factor for poor prognosis and disease progression.


Subject(s)
Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/mortality , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/mortality , Sodium-Glucose Transporter 1/metabolism , Sodium-Glucose Transporter 2/metabolism , Aged , Biomarkers, Tumor/genetics , Female , Humans , Immunohistochemistry , Male , Middle Aged , Prognosis , Proportional Hazards Models , Survival Analysis
12.
Cancer Invest ; 39(9): 741-755, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34229540

ABSTRACT

To explore the expression profile and prognostic relevance of GLUT-1 in pancreatic cancer, a meta-analysis, bioinformatics analysis based on Gene Expression Omnibus (GEO), Oncomine dataset and The Cancer Genome Atlas (TCGA) database, and immunohistochemistry in tumor and normal tissue from 88 pancreatic ductal adenocarcinoma (PDAC) patients were performed. GLUT-1 was significantly overexpressed in pancreatic cancer but it could not be a significant biomarker for prognosis. TNM stage and pathological grade could be biomarker of poor prognosis of patients with pancreatic cancer.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Pancreatic Ductal/genetics , Computational Biology/methods , Gene Expression Regulation, Neoplastic , Glucose Transporter Type 1/genetics , Pancreatic Neoplasms/genetics , Aged , Biomarkers, Tumor/metabolism , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/therapy , Female , Gene Expression Profiling/methods , Glucose Transporter Type 1/metabolism , Humans , Immunohistochemistry/methods , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/therapy , Prognosis , Retrospective Studies
13.
ACS Omega ; 6(4): 2759-2766, 2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33553894

ABSTRACT

In this work, the gas-solid flow and water vaporization process are simulated by the method of Euler-Eulerian two-fluid model in a three-dimensional spouted bed, which have a significant influence on the desulfurization efficiency. The results of simulation indicate that the change trends of the particle volume fraction are similar under superficial gas velocities of 0.7 and 0.8 m/s. The degree of particle pulsation is the highest at the bottom of the spout area, and the degree of gas pulsation is the highest at the junction of the annulus area and spout area. The temperatures of gas, liquid, and particles are also analyzed. The results demonstrate that in the spout area, the gas temperature is much higher than that of the liquid and particles, but the three phases are uniformly mixed and have similar temperatures in other areas. Moreover, water vaporization mainly occurs at the junction of the annulus area and the spout area, a small amount of liquid is vaporized at the center of the spout area, and basically no vaporization reaction occurs in the outer radius of the annulus area. With the increase in gas velocity, gas temperature, and liquid temperature and the decrease in gas humidity, water vaporization reaction is promoted.

14.
Biosci Rep ; 40(7)2020 07 31.
Article in English | MEDLINE | ID: mdl-32677676

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related death worldwide, and the mortality of patients with PDAC has not significantly decreased over the last few decades. Novel strategies exhibiting promising effects in preclinical or phase I/II clinical trials are often situated in an embarrassing condition owing to the disappointing results in phase III trials. The efficacy of the current therapeutic regimens is consistently compromised by the mechanisms of drug resistance at different levels, distinctly more intractable than several other solid tumours. In this review, the main mechanisms of drug resistance clinicians and investigators are dealing with during the exploitation and exploration of the anti-tumour effects of drugs in PDAC treatment are summarized. Corresponding measures to overcome these limitations are also discussed.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carcinoma, Pancreatic Ductal/drug therapy , Drug Resistance, Neoplasm , Pancreatic Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/antagonists & inhibitors , Biomarkers, Tumor/genetics , Carcinoma, Pancreatic Ductal/blood supply , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/mortality , Cell Hypoxia , Clinical Trials as Topic , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacology , Deoxycytidine/therapeutic use , Fluorouracil/pharmacology , Fluorouracil/therapeutic use , Gene Expression Regulation, Neoplastic/drug effects , Humans , Irinotecan/pharmacology , Irinotecan/therapeutic use , Leucovorin/pharmacology , Leucovorin/therapeutic use , Molecular Targeted Therapy/adverse effects , Molecular Targeted Therapy/methods , Mutation , Oxaliplatin/pharmacology , Oxaliplatin/therapeutic use , Pancreas/blood supply , Pancreas/drug effects , Pancreas/pathology , Pancreatic Neoplasms/blood supply , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/mortality , Progression-Free Survival , Survival Rate , Treatment Outcome , Tumor Microenvironment/drug effects , Tumor Microenvironment/genetics , Gemcitabine
15.
Mol Pharm ; 16(12): 4775-4786, 2019 12 02.
Article in English | MEDLINE | ID: mdl-31613625

ABSTRACT

The coformulation of monoclonal antibody (mAb) mixtures provides an attractive route to achieving therapeutic efficacy where the targeting of multiple epitopes is necessary. Controlling and predicting the behavior of such mixtures requires elucidating the molecular basis for the self- and cross-protein-protein interactions and how they depend on solution variables. While self-interactions are now beginning to be well understood, systematic studies of cross-interactions between mAbs in solution do not exist. Here, we have used static light scattering to measure the set of self- and cross-osmotic second virial coefficients in a solution containing a mixture of two mAbs, mAbA and mAbB, as a function of ionic strength and pH. mAbB exhibits strong association at a low ionic strength, which is attributed to an electrostatic attraction that is enhanced by the presence of a strong short-ranged attraction of nonelectrostatic origin. Under all solution conditions, the measured cross-interactions are intermediate self-interactions and follow similar patterns of behavior. There is a strong electrostatic attraction at higher pH values, reflecting the behavior of mAbB. Protein-protein interactions become more attractive with an increasing pH due to reducing the overall protein net charges, an effect that is attenuated with an increasing ionic strength due to the screening of electrostatic interactions. Under moderate ionic strength conditions, the reduced cross-virial coefficient, which reflects only the energetic contribution to protein-protein interactions, is given by a geometric average of the corresponding self-coefficients. We show the relationship can be rationalized using a patchy sphere model, where the interaction energy between sites i and j is given by the arithmetic mean of the i-i and j-j interactions. The geometric mean does not necessarily apply to all mAb mixtures and is expected to break down at a lower ionic strength due to the nonadditivity of electrostatic interactions.


Subject(s)
Antibodies, Monoclonal/metabolism , Protein Interaction Domains and Motifs/physiology , Humans , Hydrogen-Ion Concentration , Light , Osmolar Concentration , Protein Binding/physiology , Scattering, Radiation , Solutions/chemistry , Static Electricity
16.
Int J Pharm ; 568: 118512, 2019 Sep 10.
Article in English | MEDLINE | ID: mdl-31301464

ABSTRACT

Deuterium incorporation in solid-state hydrogen deuterium exchange with mass spectrometry (ssHDX-MS) has been correlated with protein aggregation on storage in sugar-based solid matrices. Here, the effects of sucrose, arginine and histidine buffer on the rate of aggregation of a lyophilized monoclonal antibody (mAb) were assessed using design of experiments (DoE) and response surface methodology. Lyophilized formulations were characterized using ssHDX-MS and Fourier transform infrared spectroscopy (ssFTIR) to assess potential correlation with stability in solid state. The samples were subjected to storage stability at 5 °C and stressed stability at 40 °C/75% RH for 6 months, and the aggregation rate was measured using size exclusion chromatography (SEC). Different levels of arginine had no significant effect on deuterium uptake in ssHDX-MS, although stability studies showed that aggregation rate decreased with increasing arginine concentration. Similarly, when histidine buffer was replaced with phosphate buffer at the same pH and molarity, ssHDX-MS showed no differences in deuterium uptake, but storage stability studies showed a significant increase in aggregation rate. The results suggest that proteins can be stabilized in amorphous solids by ionic interactions which ssHDX-MS does not detect, an important indication of the limitations of the method.


Subject(s)
Antibodies, Monoclonal/chemistry , Arginine/chemistry , Immunoglobulin G/chemistry , Sucrose/chemistry , Deuterium/chemistry , Deuterium Exchange Measurement , Histidine/chemistry , Mass Spectrometry , Phosphates/chemistry , Protein Conformation , Protein Stability
17.
Biotechnol Prog ; 35(1): e2732, 2019 01.
Article in English | MEDLINE | ID: mdl-30320962

ABSTRACT

A stochastic approach of copurification of the protease Cathepsin L that results in product fragmentation during purification processing and storage is presented. Cathepsin L was identified using mass spectroscopy, characterization of proteolytic activity, and comparison with fragmentation patterns observed using recombinant Cathepsin L. Cathepsin L existed in Chinese hamster ovary cell culture fluids obtained from cell lines expressing different products and cleaved a variety of recombinant proteins including monoclonal antibodies, antibody fragments, bispecific antibodies, and fusion proteins. Therefore, characterization its chromatographic behavior is essential to ensure robust manufacturing and sufficient shelf life. The chromatographic behaviors of Cathepsin L using a variety of techniques including affinity, cation exchange, anion exchange, and mixed mode chromatography were systematically evaluated. Our data demonstrates that copurification of Cathepsin L on nonaffinity modalities is principally because of similar retention on the stationary phase and not through interactions with product. Lastly, Cathespin L exhibits a broad elution profile in cation exchange chromatography (CEX) likely because of its different forms. Affinity purification is free of fragmentation issue, making affinity capture the best mitigation of Cathepsin L. When affinity purification is not feasible, a high pH wash on CEX can effectively remove Cathepsin L but resulted in significant product loss, while anion exchange chromatography operated in flow-through mode does not efficiently remove Cathepsin L. Mixed mode chromatography, using Capto™ adhere in this example, provides robust clearance over wide process parameter range (pH 7.7 ± 0.3 and 100 ± 50 mM NaCl), making it an ideal technique to clear Cathepsin L. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2732, 2019.


Subject(s)
Proteomics/methods , Animals , CHO Cells , Cathepsin L , Chromatography, Affinity , Chromatography, Ion Exchange , Cricetinae , Cricetulus , Hydrogen-Ion Concentration , Proteolysis , Recombinant Proteins/metabolism
18.
Int J Biol Macromol ; 117: 610-616, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29802926

ABSTRACT

Two novel heteropolysaccharides (JCH-1 and JCH-2) with molecular weights of 30.9 and 555.3 kDa were first extracted, isolated and purified from Isaria cicadae Miquel (I. Miquel). Monosaccharide analysis showed that JCH-1 and JCH-2 were composed of mannose, glucose and galactose with different monosaccharide ratio. In addition, JCH-1 had higher contents of sulfated and uronic acid compared to JCH-2. Based on MTT assay, JCH-1 and JCH-2 could markedly promote the proliferation of RAW264.7 cells and exhibit no cytotoxicity at a specific concentration range. The immunomodulatory assay exhibited that JCH-1 and JCH-2 could significantly enhance the viability of macrophage cells, and promote the release of NO, IL-6 and TNF-α. Furthermore, the immunomodulatory activity of JCH-1 was significantly better than that of JCH-2. These results proposed that I. Miquel had two polysaccharide fractions with different composition and JCH-1 is better to be developed as a functional food with the better immunomodulator activity.


Subject(s)
Cell Proliferation/drug effects , Cordyceps/chemistry , Immunologic Factors/isolation & purification , Polysaccharides/isolation & purification , Animals , Cell Differentiation/drug effects , Cell Survival/drug effects , Cordyceps/immunology , Galactose/chemistry , Gene Expression Regulation/drug effects , Glucose/chemistry , Immunologic Factors/chemistry , Immunologic Factors/immunology , Immunologic Factors/pharmacology , Interleukin-6/genetics , Mannose/chemistry , Mice , Nitric Oxide/genetics , Polysaccharides/chemistry , Polysaccharides/immunology , Polysaccharides/pharmacology , RAW 264.7 Cells , Tumor Necrosis Factor-alpha/genetics , Uronic Acids/chemistry
19.
Environ Technol ; 39(23): 3096-3103, 2018 Dec.
Article in English | MEDLINE | ID: mdl-28859597

ABSTRACT

A high-ammonia-resistant strain was firstly isolated from activated sludge and applied to harvest a bioflocculant from a swine wastewater. Enhancement of swine wastewater treatment was investigated by a composite of the harvested bioflocculant and a zeolite modified by integrating calcinations with MgO at 400°C. Results have demonstrated that 71.8% of Chemical Oxygen Demand (COD), 54.5% of ammonia, and 81.2% of turbidity can be removed from the swine wastewater by the bioflocculant alone. Results have also demonstrated that 73.4% of ammonia could be removed from the swine wastewater by the modified zeolite alone, while almost no COD was removed. Thus, the bioflocculant and modified zeolite were used simultaneously to enhance swine wastewater treatment, and response surface methodology (RSM) was employed to optimize the treatment process. Under the optimal treatment conditions of bioflocculant of 12 mg/L, modified zeolite of 8 g/L, pH of 7.5, and agitation speed of 200 r/min, obtained by the RSM, 88.6% of COD, 85.8% of ammonia, and 95.5% of turbidity could be removed from swine wastewater, which were significantly improved compared with that by the bioflocculant or modified zeolite alone. The use of the composite exerted advantages of the bioflocculant and modified zeolite, and provided a feasible way to improve pollutants' removal from wastewaters.


Subject(s)
Water Purification , Zeolites , Animals , Flocculation , Sewage , Swine , Wastewater
20.
Int J Biol Macromol ; 93(Pt A): 879-888, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27645928

ABSTRACT

The purpose of this study was to investigate the extraction, characterization and bioactivities of purified water-soluble polysaccharides (BCP) from Baphicacanthis Cusiae Rhizoma et Radix. Based on the response surface methodology, the optimal extraction parameters were obtained as follows: extraction temperature of 60.0°C, extraction time of 35.0min, and ratio of water to raw material of 24.5ml/g. Then, BCP was separated and purified by chromatography of DEAE-52 and Sephadex G-100, and obtained two purified fractions, named as BCP-1 and BCP-2. Their molecular weights were respectively 11.6 and 26.7 KDa with mainly composed of glucose, arabinose and galactose. BCP-2 had higher contents of sulfuric radical and uronic acid than BCP-1. Finally, their antioxidant and anti-inflammatory activities were evaluated. Both of BCP-1 and BCP-2 exhibited strong antioxidant activity in vitro, and the antioxidant of BCP-2 was better. Besides, they showed ideal anti-inflammatory activity in vitro and in vivo.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Free Radical Scavengers/pharmacology , Plant Extracts/pharmacology , Polysaccharides/pharmacology , Acanthaceae/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Capillary Permeability/drug effects , Chromatography, Gel , Chromatography, Ion Exchange , Drug Evaluation, Preclinical , Edema/chemically induced , Edema/drug therapy , Free Radical Scavengers/chemistry , Free Radical Scavengers/isolation & purification , Iron Chelating Agents/chemistry , Iron Chelating Agents/isolation & purification , Iron Chelating Agents/pharmacology , Male , Mice , Molecular Weight , Nitric Oxide/metabolism , Oxidation-Reduction , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Polysaccharides/chemistry , Polysaccharides/isolation & purification , RAW 264.7 Cells , Rhizome/chemistry , Xylenes
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