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1.
Sci Rep ; 14(1): 4270, 2024 02 21.
Article in English | MEDLINE | ID: mdl-38383712

ABSTRACT

Colorectal cancer is a prevalent malignancy with global significance. This retrospective study aimed to investigate the influence of stage and tumor site on survival outcomes in 284 colorectal cancer patients diagnosed between 2001 and 2017. Patients were categorized into four groups based on tumor site (colon and rectum) and disease stage (early stage and advanced stage). Demographic characteristics, treatment modalities, and survival outcomes were recorded. Bayesian survival modeling was performed using semi-competing risks illness-death models with an accelerated failure time (AFT) approach, utilizing R 4.1 software. Results demonstrated significantly higher time ratios for disease recurrence (TR = 1.712, 95% CI 1.489-2.197), mortality without recurrence (TR = 1.933, 1.480-2.510), and mortality after recurrence (TR = 1.847, 1.147-2.178) in early-stage colon cancer compared to early-stage rectal cancer. Furthermore, patients with advanced-stage rectal cancer exhibited shorter survival times for disease recurrence than patients with early-stage colon cancer. The interaction effect between the disease site and cancer stage was not significant. These findings, derived from the optimal Bayesian log-normal model for terminal and non-terminal events, highlight the importance of early detection and effective management strategies for colon cancer. Early-stage colon cancer demonstrated improved survival rates for disease recurrence, mortality without recurrence, and mortality after recurrence compared to other stages. Early intervention and comprehensive care are crucial to enhance prognosis and minimize adverse events in colon cancer patients.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Rectal Neoplasms , Humans , Retrospective Studies , Bayes Theorem , Neoplasm Recurrence, Local/pathology , Colonic Neoplasms/pathology , Rectal Neoplasms/pathology , Prognosis , Neoplasm Staging , Colorectal Neoplasms/pathology
2.
Sci Rep ; 12(1): 6583, 2022 04 21.
Article in English | MEDLINE | ID: mdl-35449188

ABSTRACT

In this study, Amoxicillin (AMX) was loaded on laponite (LAP) nanoplates and then immobilized on the surface of electrospun polylactic acid (PLA) nanofibers to fabricate scaffolds with osteoinductive and antibacterial activities. The highest loading efficiency (49%) was obtained when the concentrations of AMX and LAP were 3 mg/mL and 1 mg/mL, respectively. FTIR and XRD spectroscopies and zeta potentiometry confirmed the successful encapsulating of AMX within LAP nanoplates. The immobilization of AMX-loaded LAPs on the surface of PLA nanofibers was verified by SEM and FTIR spectroscopy. In vitro release study showed a two-phase AMX release profile for the scaffolds; an initial burst release within the first 48 h and a later sustained release up to 21 days. In vitro antibacterial tests against Staphylococcus aureus and Escherichia coli presented the ability of scaffolds to inhibit the growth of both bacteria. The biocompatibility assays revealed the attachment and viability of human bone marrow mesenchymal stem cells (hBMSCs) cultured on the surface of scaffolds (p ≤ 0.05). The increased ALKALINE PHOSPHATASE (ALP) activity (p ≤ 0.001), calcium deposition, and expression of ALP and OSTEONECTIN genes indicated the osteoinductivity of functionalized scaffolds for hBMSCs. These LAP/AMX-functionalized scaffolds might be desirable candida for the treatment of bone defects.


Subject(s)
Amoxicillin , Nanofibers , Amoxicillin/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Escherichia coli , Humans , Nanofibers/chemistry , Polyesters/chemistry , Silicates , Tissue Engineering/methods , Tissue Scaffolds/chemistry
3.
J Neuroeng Rehabil ; 18(1): 20, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33526049

ABSTRACT

BACKGROUND: Regularity, quantified by sample entropy (SampEn), has been extensively used as a gait stability measure. Yet, there is no consensus on the calculation process and variant approaches, e.g. single-scale SampEn with and without incorporating a time delay greater than one, multiscale SampEn, and complexity index, have been used to calculate the regularity of kinematic or kinetic signals. The aim of the present study was to test the discriminatory performance of the abovementioned approaches during single and dual-task walking in people with Parkinson's disease (PD). METHODS: Seventeen individuals with PD were included in this study. Participants completed two walking trials that included single and dual-task conditions. The secondary task was word searching with twelve words randomly appearing in the participants' visual field. Trunk linear acceleration at sternum level, linear acceleration of the center of gravity, and angular velocity of feet, shanks, and thighs, each in three planes of motion were collected. The regularity of signals was computed using approaches mentioned above for single and dual-task conditions. RESULTS: Incorporating a time delay greater than one and considering multiple scales helped better distinguish between single and dual-task walking. For all signals, the complexity index, defined as the summary of multiscale SampEn analysis, was the most efficient discriminatory index between single-task walking and dual-tasking in people with Parkinson's disease. Specifically, the complexity index of the trunk linear acceleration of the center of gravity distinguished between the two walking conditions in all three planes of motion. CONCLUSIONS: The significant results observed across the 24 signals studied in this study are illustrative examples of the complexity index's potential as a gait feature for classifying different walking conditions.


Subject(s)
Gait Analysis/methods , Gait Disorders, Neurologic/physiopathology , Parkinson Disease/complications , Aged , Biomechanical Phenomena , Entropy , Exercise Test , Female , Gait Disorders, Neurologic/etiology , Humans , Male , Middle Aged , Parkinson Disease/physiopathology , Walking
4.
Med Eng Phys ; 74: 49-57, 2019 12.
Article in English | MEDLINE | ID: mdl-31623942

ABSTRACT

Steady state gait dynamics has been examined using the measures of regularity, local dynamic stability, and variability. This study investigates the relationship between these measures under increasing cognitive loads. Participants walked on an instrumented treadmill at 1 m/s under walk only and two dual-task conditions. The secondary tasks were visuomotor cognitive games (VCG) of increasing difficulty level. The center of pressure displacement in the mediolateral direction (ML COP-D) and cognitive game performance were recorded for analysis. The following measures were calculated: (1) sample entropy (SampEn) and quantized dynamical entropy (QDE) of the ML COP-D, (2) short-term largest Lyapunov exponent (LLE) of the ML COP-D, and (3) variability of inter-stride spatio-temporal gait variables. Entropy and variability measures significantly increased from walk only to both dual-task conditions. Whereas, the short-term LLE increased only during the easy VCG task. No measure was sensitive to the difficulty level of the VCG tasks. The variability of heel strike positions in the mediolateral direction was positively correlated with SampEn and QDE. However, there were no significant correlations between the short-term LLE and either variability measures or entropy measures. These findings confirm that each of these measures is representative of a different aspect of human gait dynamics.


Subject(s)
Exercise Test , Gait Analysis/methods , Pressure , Walking/physiology , Adult , Female , Healthy Volunteers , Humans , Male
5.
J Econ Entomol ; 111(6): 2667-2675, 2018 12 14.
Article in English | MEDLINE | ID: mdl-30032285

ABSTRACT

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive pests of tomato worldwide. Biological control of the pest using Trichogramma (Hymenoptera: Trichogrammatidae) wasps can be combined with other practices such as use of synthetic sex pheromones for mating disruption or mass trapping programs. In this study, effects of T. absoluta sex pheromone on behavioral responses and fertility life table parameters of Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae), Wolbachia-uninfected (W-) Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae), and Wolbachia-infected (W+) T. brassicae were investigated under laboratory conditions. Female wasps of T. evanescens and T. brassicae (W+) were attracted to the pest synthetic sex pheromone (around 62%) and calling virgin female moths (around 75%) and their responses were affected by the wasp age and temperature. Exposure to the host synthetic sex pheromone significantly reduced the percentage of adult emergence, longevity, and fecundity of female wasps, as well as the time spent to find a mate and duration of mating. However, tested populations were not affected similarly. Despite the laboratory tests, greenhouse experiments showed that the wasps were not caught in the traps baited with T. absoluta synthetic sex pheromone. Complementary studies are needed to precisely determine possible interference between pheromone application and releasing Trichogramma Westwood (Hymenoptera: Trichogrammatidae) wasps to achieve a successful integrated control of T. absoluta.


Subject(s)
Moths/parasitology , Sex Attractants/pharmacology , Sexual Behavior, Animal/drug effects , Wasps/physiology , Animals , Female , Male , Moths/chemistry , Wasps/microbiology , Wolbachia/physiology
6.
Entropy (Basel) ; 20(8)2018 Aug 06.
Article in English | MEDLINE | ID: mdl-33265668

ABSTRACT

Sample entropy (SampEn) has been used to quantify the regularity or predictability of human gait signals. There are studies on the appropriate use of this measure for inter-stride spatio-temporal gait variables. However, the sensitivity of this measure to preprocessing of the signal and to variant values of template size (m), tolerance size (r), and sampling rate has not been studied when applied to "whole" gait signals. Whole gait signals are the entire time series data obtained from force or inertial sensors. This study systematically investigates the sensitivity of SampEn of the center of pressure displacement in the mediolateral direction (ML COP-D) to variant parameter values and two pre-processing methods. These two methods are filtering the high-frequency components and resampling the signals to have the same average number of data points per stride. The discriminatory ability of SampEn is studied by comparing treadmill walk only (WO) to dual-task (DT) condition. The results suggest that SampEn maintains the directional difference between two walking conditions across variant parameter values, showing a significant increase from WO to DT condition, especially when signals are low-pass filtered. Moreover, when gait speed is different between test conditions, signals should be low-pass filtered and resampled to have the same average number of data points per stride.

7.
J Biomech Eng ; 140(1)2018 Jan 01.
Article in English | MEDLINE | ID: mdl-28975279

ABSTRACT

Quantized dynamical entropy (QDE) has recently been proposed as a new measure to quantify the complexity of dynamical systems with the purpose of offering a better computational efficiency. This paper further investigates the viability of this method using five different human gait signals. These signals are recorded while normal walking and while performing secondary tasks among two age groups (young and older age groups). The results are compared with the outcomes of previously established sample entropy (SampEn) measure for the same signals. We also study how analyzing segmented and spatially and temporally normalized signal differs from analyzing whole data. Our findings show that human gait signals become more complex as people age and while they are cognitively loaded. Center of pressure (COP) displacement in mediolateral direction is the best signal for showing the gait changes. Moreover, the results suggest that by segmenting data, more information about intrastride dynamical features are obtained. Most importantly, QDE is shown to be a reliable measure for human gait complexity analysis.


Subject(s)
Aging/physiology , Entropy , Exercise Test , Gait , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Young Adult
8.
PLoS One ; 12(10): e0185967, 2017.
Article in English | MEDLINE | ID: mdl-29023479

ABSTRACT

In recent years, monoclonal antibodies (mAbs) have been developed as powerful therapeutic and diagnostic agents and Chinese hamster ovary (CHO) cells have emerged as the dominant host for the recombinant expression of these proteins. A critical step in recombinant expression is the utilization of strong promoters, such as the Chinese Hamster Elongation Factor-1α (CHEF-1) promoter. To compare the strengths of CHEF with cytomegalovirus (CMV) promoter for mAb expression in CHO cells, four bicistronic vectors bearing either internal ribosome entry site (IRES) or Furin/2A (F2A) sequences were designed. The efficiency of these promoters was evaluated by measuring level of expressed antibody in stable cell pools. Our results indicated that CHEF promoter-based expression of mAbs was 2.5 fold higher than CMV-based expression in F2A-mediated vectors. However, this difference was less significant in IRES-mediated mAb expressing cells. Studying the stability of the F2A expression system in the course of 18 weeks, we observed that the cells having CHEF promoter maintained their antibody expression at higher level than those transfected with CMV promoter. Further analyses showed that both IRES-mediated vectors, expressed mAbs with correct size, whereas in antibodies expressed via F2A system heterogeneity of light chains were detected due to incomplete furin cleavage. Our findings indicated that the CHEF promoter is a viable alternative to CMV promoter-based expression in F2A-mediated vectors by providing both higher expression and level of stability.


Subject(s)
Antibodies, Monoclonal/genetics , Cytomegalovirus/genetics , Internal Ribosome Entry Sites , Peptide Elongation Factor 1/genetics , Promoter Regions, Genetic , Animals , Antibodies, Monoclonal/isolation & purification , Antibodies, Monoclonal/metabolism , Blotting, Western , CHO Cells , Cricetulus , Furin/genetics , Genetic Vectors , Protein Engineering/methods , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
9.
PLoS One ; 12(6): e0179902, 2017.
Article in English | MEDLINE | ID: mdl-28662065

ABSTRACT

Establishing stable Chinese Hamster Ovary (CHO) cells producing monoclonal antibodies (mAbs) usually pass through the random integration of vectors to the cell genome, which is sensitive to gene silencing. One approach to overcome this issue is to target a highly transcribed region in the genome. Transposons are useful devices to target active parts of genomes, and PiggyBac (PB) transposon can be considered as a good option. In the present study, three PB transposon donor vectors containing both heavy and light chains were constructed, one contained independent expression cassettes while the others utilized either an Internal Ribosome Entry Site (IRES) or 2A element to express mAb. Conventional cell pools were created by transferring donor vectors into the CHO cells, whereas transposon-based cells were generated by transfecting the cells with donor vectors with a companion of a transposase-encoding helper vector, with 1:2.5 helper/donor vectors ratio. To evaluate the influence of helper/donor vectors ratio on expression, the second transposon-based cell pools were generated with 1:5 helper/donor ratio. Expression levels in the transposon-based cells were two to five -folds more than those created by conventional method except for the IRES-mediated ones, in which the observed difference increased more than 100-fold. The results were dependent on both donor vector design and vectors ratios.


Subject(s)
Antibodies, Monoclonal/genetics , DNA Transposable Elements , Nerve Tissue Proteins/genetics , Animals , CHO Cells , Cricetinae , Cricetulus , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction
10.
Protein Expr Purif ; 134: 89-95, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28400295

ABSTRACT

OBJECTIVES: Several types of expression vectors have been used for recombinant protein expression in Chinese hamster ovary cells (CHO) which usually result in variable and unstable levels of expression. METHODS AND RESULTS: In this study, we have compared the mAb0014 expression level of single ORF/IRES vector and dual ORF vector in the presence and absence of phiC31 integrase targeting system. Both expression vectors contain an elongation factor 1α (EF1α) promoter upstream of LC and harboring an attB site. CHO-S cells were co-transfected with single ORF/IRES or dual ORF vectors along with a phiC31 integrase expression vector which can catalyze recombination between attB site and pseudo-attP sites presented in the mammalian genome. Our results demonstrated that dual ORF vector in the presence of phiC31 integrase expression vectors (+FC31 2P) generated more recombinant antibody in comparison to its negative control (-FC31 2P). Moreover, both of +FC31 2P and -FC31 2P cell pools yield higher recombinant protein in comparison to single ORF/IRES vector (FC31 IRES) cell pools. Stability of expression in phiC31 co-transfected cell pools (+FC31 2P and +FC31 IRES) had no considerable changes. CONCLUSIONS: Our results indicated that the dual ORF vector using integrase can support the generation of cell lines with stable transgene expression at an elevated mAb relative to single ORF/IRES vector.


Subject(s)
Antibodies, Monoclonal , Gene Expression , Genetic Vectors/genetics , Integrases , Animals , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/genetics , Attachment Sites, Microbiological , CHO Cells , Cricetinae , Cricetulus , Integrases/biosynthesis , Integrases/genetics , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Transgenes
11.
BMC Biotechnol ; 17(1): 18, 2017 02 22.
Article in English | MEDLINE | ID: mdl-28228095

ABSTRACT

BACKGROUND: As the demand for monoclonal antibodies (mAb) increases, more efficient expression methods are required for their manufacturing process. Transcriptional gene silencing is a common phenomenon in recombinant cell lines which leads to expression reduction and instability. There are reports on improved antibody expression in ubiquitous chromatin opening element (UCOE) containing both heavy and light chain gene constructs. Here we investigate the impact of having these elements as part of the light chain, heavy chain or both genes during cell line development. In this regard, non-UCOE and UCOE vectors were constructed and stable Chinese hamster ovary (CHO) cell pools were generated by different vector combinations. RESULTS: Expression analysis revealed that all UCOE cell pools had higher antibody yields compared to non-UCOE cells, Moreover the most optimal expression was obtained by cells containing just the UCOE on heavy chain. In terms of stability, it was shown that the high level of expression was kept consistence for more than four months in these cells whereas the expression titers were reduced in the other UCOE pools. CONCLUSIONS: In conclusion, UCOE significantly enhanced the level and stability of antibody expression and the use of this element with heavy chain provided more stable cell lines with higher production level.


Subject(s)
Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/genetics , Chromatin/genetics , Gene Expression Regulation/genetics , Genetic Vectors/genetics , Protein Engineering/methods , Animals , CHO Cells , Cricetulus , Promoter Regions, Genetic/genetics , Transgenes/genetics
12.
Biotechnol Prog ; 32(6): 1570-1576, 2016 11.
Article in English | MEDLINE | ID: mdl-27604579

ABSTRACT

Traditional methods to generate CHO cell lines rely on random integration(s) of the gene of interest and result in unpredictable and unstable protein expression. In comparison, site-specific recombination methods increase the recombinant protein expression by inserting transgene at a locus with specific expression features. PhiC31 serine integrase, catalyze unidirectional integration that occurs at higher frequency in comparison with the reversible integration carried out by recombinases such as Cre. In this study, using different ratios of phiC31 serine integrase, we evaluated the phiC31 mediated gene integration for expression of a humanized IgG1 antibody (mAb0014) in CHO-S cells. Light chain (LC) and heavy chain (HC) genes were expressed in one operon under EF1α promoter and linked by internal ribosome entry site (IRES) element. The clonal selection was carried out by limiting dilution. Targeted integration approach increased recombinant protein yield and stability in cell pools. The productivity of targeted cell pools was about 4 mg/L and about 40 µg/L in the control cell pool. The number of integrated transgenes was about 19 fold higher than the control cells pools. Our results confirmed that the phiC31 integrase leads to mAb expression in more than 90% of colonies. The productivity of the PhiC31 integrated cell pools was stable for three months in the absence of selection as compared with conventional transfection methods. Hence, utilizing PhiC31 integrase can increase protein titer and decrease the required time for protein expression. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1570-1576, 2016.


Subject(s)
Antibodies, Monoclonal/genetics , Integrases/metabolism , Animals , CHO Cells , Cells, Cultured , Cricetulus , Integrases/genetics , RNA, Messenger/genetics
13.
J Ayurveda Integr Med ; 5(3): 162-6, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25336847

ABSTRACT

BACKGROUND: Nowadays, owing to medicinal plants as a candidate to obtain promising new medicinal agents, there is a renewed interest in the use of these natural sources for drug development. OBJECTIVE: In the present study, we aimed to assess the anticholinesterase, antioxidant, and neuropotective effects of Tripleurospermum disciforme and Dracocephalum multicaule extracts. MATERIALS AND METHODS: Methanolic extract of the plants was prepared by maceration method. Anticholinesterase effect of different concentrations of the plants was studied by colorimetric method and antioxidant activity was evaluated using diphenypicrylhydrazil (DPPH) assay. Protective effect of the extracts against amyloid ß (Aß)-induced toxicity in PC12 cells was determined by MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) method. RESULTS: Both T. disciforme and D. multicaule extracts could inhibit acetylcholinesterase (AChE) in a dose-dependent manner. The highest inhibition occurred at 5 µg/ml (71.18 ± 4.9 and 79.06 ± 3.1% inhibition respectively by T. disciforme and D. multicaule) in comparison to tacrine (86.37 ± 3.24%). The greatest DPPH inhibition of T. disciforme and D. multicaule was shown at 800 µg/ml (89.04 ± 3.9 and 78.5 ± 3.7%, respectively). None of tested extracts induced protection against ßA toxicity in PC12 cell. CONCLUSION: Although the results indicated anticholinesterase and antioxidant of the T. disciforme and D. multicaule, further specific studies and scientific validity are needed.

14.
Asian Pac J Cancer Prev ; 14(12): 7561-8, 2013.
Article in English | MEDLINE | ID: mdl-24460334

ABSTRACT

Galectin-3 (Gal-3) is a carbohydrate-binding protein which is thought to be involved in cancer progression but its contribution to epithelial ovarian cancer (EOC) remains unclear. The present study sought to determine the role of Gal-3 in chemoresistance of the human SKOV-3 ovarian cancer cell line to paclitaxel (PTX) using recombinant human Gal-3 (rhGal-3) and PectaSol-C modified citrus pectin (Pect-MCP) as a specific Gal-3 competitive inhibitor. Our results showed 41% increased cell proliferation, 36% decreased caspase-3 activity and 33.6% increased substrate-dependent adhesion in the presence of rhGal-3 compared to the control case (p<0.001). Treatment of cells with a non-effective dose of PTX (100nM) and 0.1% Pect-MCP in combination revealed synergistic cytotoxic effects with 75% reduced cell viability and subsequent 3.9-fold increase in caspase-3 activity. Moreover, there was 39% decrease in substrate-dependent adhesion compared to control (p<0.001). These results suggest that inhibition of Gal-3 could be a useful therapeutic tool for combination therapy of ovarian cancer.


Subject(s)
Apoptosis/drug effects , Citrus/chemistry , Galectin 3/antagonists & inhibitors , Ovarian Neoplasms/pathology , Paclitaxel/pharmacology , Pectins/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Blood Proteins , Blotting, Western , Cell Adhesion/drug effects , Cell Cycle/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Drug Synergism , Female , Galectins , Humans , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Umbilical Cord
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