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1.
Clin Radiol ; 2024 May 16.
Article in English | MEDLINE | ID: mdl-38876960

ABSTRACT

AIMS: This study aimed to predict the expression of programmed death-1 (PD-1) in non-small cell lung cancer (NSCLC) using intratumoral and peritumoral computed tomography (CT) radiomics nomogram. MATERIALS AND METHODS: Two hundred patients pathologically diagnosed with NSCLC from two hospitals were retrospectively analyzed. Of these, 159 NSCLC patients from our hospital were randomly divided into a training cohort (n=96) and an internal validation cohort (n=63) at a ratio of 6:4, while 41 NSCLC patients from another medical institution served as the external validation cohort. The radiomic features of the gross tumor volume (GTV) and peritumoral volume (PTV) were extracted from the CT images. Optimal radiomics features were selected using least absolute shrinkage and selection operator regression analysis. Finally, a CT radiomics nomogram of clinically independent predictors combined with the best rad-score was constructed. RESULTS: Compared with the 'GTV' and 'PTV' radiomics models, the combined 'GTV + PTV' radiomics model showed better predictive performance, and its area under the curve (AUC) values in the training, internal validation, and external validation cohorts were 0.90 (95% confidence interval [CI]: 0.83-0.97), 0.85 (95% CI: 0.74-0.96) and 0.78 (95% CI: 0.63-0.92). The nomogram constructed by the rad-score of the 'GTV + PTV' radiomics model combined with clinical independent predictors (prealbumin and monocyte) had the best performance, with AUC values in each cohort being 0.92 (95% CI: 0.85-0.98), 0.88 (95% CI: 0.78-0.97), and 0.80 (95% CI: 0.66-0.94), respectively. CONCLUSION: The intratumoral and peritumoral CT radiomics nomogram may facilitate individualized prediction of PD-1 expression status in patients with NSCLC.

2.
Carbohydr Polym ; 335: 122063, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38616074

ABSTRACT

The surface properties of cardiovascular biomaterials play a critical role in their biological responses. Although bacterial nanocellulose (BNC) materials have exhibited potential applications in cardiovascular implants, the impact of their surface characteristics on biocompatibility has rarely been studied. This study investigated the mechanism for the biocompatibility induced by the physicochemical properties of both sides of BNC. With greater wettability and smoothness, the upper BNC surface reduced protein adsorption by 25 % compared with the lower surface. This prolonged the plasma re-calcification time by 14 % in venous blood. Further, compared with the lower BNC surface, the upper BNC surface prolonged the activated partial thromboplastin time by 5 % and 4 % in arterial and venous blood, respectively. Moreover, the lower BNC surface with lesser rigidity, higher roughness, and sparser fiber structure promoted cell adhesion. The lower BNC surface enhanced the proliferation rate of L929 and HUVECs cells by 15 % and 13 %, respectively, compared with the upper BNC surface. With lesser stiffness, the lower BNC surface upregulated the expressions of CD31 and eNOS while down-regulating the ICAM-1 expression - This promoted the proliferation of HUVECs. The findings of this study will provide valuable insights into the design of blood contact materials and cardiovascular implants.


Subject(s)
Biocompatible Materials , Body Fluids , Humans , Adsorption , Biocompatible Materials/pharmacology , Calcification, Physiologic , Human Umbilical Vein Endothelial Cells
3.
Int J Biol Macromol ; 268(Pt 2): 131685, 2024 May.
Article in English | MEDLINE | ID: mdl-38641268

ABSTRACT

There is an increasing demand for small-diameter blood vessels. Currently, there is no clinically available small-diameter artificial vessel. Bacterial nanocellulose (BNC) has vast potential for applications in artificial blood vessels due to its good biocompatibility. At the same time, medical polyurethane (PU) is a highly elastic polymer material widely used in artificial blood vessels. This study reports a composite small-diameter BNC/PU conduit using a non-solvent-induced phase separation method with the highly hydrophilic BNC tube as the skeleton and the hydrophobic polycarbonate PU as the filling material. The results revealed that the compliance and mechanical matching of BNC/PU tubes were higher than BNC tubes; the axial/radial mechanical strength, burst pressure, and suture strength were significantly improved; the blood compatibility and cell compatibility were also excellent. The molecular and subcutaneous embedding tests showed that the composite tubes had lighter inflammatory reactions. The results of the animal substitution experiments showed that the BNC/PU tubes kept blood flow unobstructed without tissue proliferation after implantation in rats for 9 months. Thus, the BNC/PU small-diameter vascular prosthesis had the potential for long-term patency and acted as an ideal material for small-diameter vessels.


Subject(s)
Blood Vessel Prosthesis , Cellulose , Polyurethanes , Polyurethanes/chemistry , Cellulose/chemistry , Animals , Rats , Materials Testing , Biocompatible Materials/chemistry , Elasticity , Humans , Male , Blood Vessels
4.
Int J Biol Macromol ; 266(Pt 1): 130646, 2024 May.
Article in English | MEDLINE | ID: mdl-38460632

ABSTRACT

The development of bio-based hemodialysis membranes continues to be a challenge. Bacterial nanocellulose (BNC) membranes show potential in hemodialysis but can hardly retain beneficial proteins. Here, chitosan particles/bacterial nanocellulose (CSP/BNC) membranes were designed to efficiently remove uremic toxins and retain beneficial proteins. First, CSPs were synthesized in situ within a BNC membrane by ionic gelation following negative pressure impregnation. Subsequently, these membranes were thoroughly characterized. Compared with the BNC membrane, the pore volume and pore size of the 3 % CSP/BNC membrane decreased by 42.2 % and 32.1 %, respectively. The increased 22.2 times of Young's modulus and 88.9 % of tensile strength in the 3 % CSP/BNC membrane confirmed enhanced mechanical property. The sieving coefficient of bovine serum albumin decreased to 0.05 ± 0.03 in the 3 % CSP/BNC membrane. Moreover, the CSP/BNC membrane exhibited good hemocompatibility and cytocompatibility. The simulated dialysis results showed that the 3 % CSP/BNC membrane exhibited high clearance of urea (16.37 %/cm2) and lysozyme (3.54 %/cm2), while efficiently retaining bovine serum albumin (98.04 %/cm2). This is the first demonstration of the construction of a BNC-based hemodialysis membrane with in situ CSP formation to effectively regulate the pore properties of the membrane, making the CSP/BNC membrane a promising candidate for hemodialysis applications.


Subject(s)
Cellulose , Chitosan , Membranes, Artificial , Renal Dialysis , Chitosan/chemistry , Cellulose/chemistry , Serum Albumin, Bovine/chemistry , Animals , Humans , Porosity , Nanoparticles/chemistry , Cattle , Urea/chemistry , Muramidase/chemistry
5.
Clin Radiol ; 78(10): e741-e751, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37487841

ABSTRACT

AIM: To develop and validate a computed tomography (CT)-based radiomics nomogram for preoperative prediction of microsatellite instability (MSI) status and clinical outcomes in colorectal cancer (CRC) patients. MATERIALS AND METHODS: This retrospective study enrolled 497 CRC patients from three centres. Least absolute shrinkage and selection operator regression was utilised for feature selection and constructing the radiomics signature. Univariate and multivariate logistic regression analyses were employed to identify significant clinical variables. The radiomics nomogram was constructed by integrating the radiomics signature and the identified clinical variables. The performance of the nomogram was evaluated through receiver operating characteristic curves, calibration curves, and decision curve analysis. Kaplan-Meier analysis was performed to investigate the prognostic value of the nomogram. RESULTS: The radiomics signature comprised 10 radiomics features associated with MSI status. The nomogram, integrating the radiomics signature and independent predictors (age, location, and thickness), demonstrated favourable calibration and discrimination, achieving areas under the receiver operating characteristic (ROC) curves (AUCs) of 0.89 (95% confidence interval [CI]: 0.83-0.95), 0.87 (95% CI: 0.79-0.95), 0.88 (95% CI: 0.81-0.96), and 0.86 (95% CI: 0.78-0.93) in the training cohort, internal validation cohort, and two external validation cohorts, respectively. The nomogram exhibited superior performance compared to the clinical model (p<0.05). Additionally, survival analysis demonstrated that the nomogram successfully stratified stage II CRC patients based on prognosis (hazard ratio [HR]: 0.357, p=0.022). CONCLUSION: The radiomics nomogram demonstrated promising performance in predicting MSI status and stratifying the prognosis of patients with CRC.

6.
Ann Oncol ; 34(9): 813-825, 2023 09.
Article in English | MEDLINE | ID: mdl-37330052

ABSTRACT

BACKGROUND: The isolation of cell-free DNA (cfDNA) from the bloodstream can be used to detect and analyze somatic alterations in circulating tumor DNA (ctDNA), and multiple cfDNA-targeted sequencing panels are now commercially available for Food and Drug Administration (FDA)-approved biomarker indications to guide treatment. More recently, cfDNA fragmentation patterns have emerged as a tool to infer epigenomic and transcriptomic information. However, most of these analyses used whole-genome sequencing, which is insufficient to identify FDA-approved biomarker indications in a cost-effective manner. PATIENTS AND METHODS: We used machine learning models of fragmentation patterns at the first coding exon in standard targeted cancer gene cfDNA sequencing panels to distinguish between cancer and non-cancer patients, as well as the specific tumor type and subtype. We assessed this approach in two independent cohorts: a published cohort from GRAIL (breast, lung, and prostate cancers, non-cancer, n = 198) and an institutional cohort from the University of Wisconsin (UW; breast, lung, prostate, bladder cancers, n = 320). Each cohort was split 70%/30% into training and validation sets. RESULTS: In the UW cohort, training cross-validated accuracy was 82.1%, and accuracy in the independent validation cohort was 86.6% despite a median ctDNA fraction of only 0.06. In the GRAIL cohort, to assess how this approach performs in very low ctDNA fractions, training and independent validation were split based on ctDNA fraction. Training cross-validated accuracy was 80.6%, and accuracy in the independent validation cohort was 76.3%. In the validation cohort where the ctDNA fractions were all <0.05 and as low as 0.0003, the cancer versus non-cancer area under the curve was 0.99. CONCLUSIONS: To our knowledge, this is the first study to demonstrate that sequencing from targeted cfDNA panels can be utilized to analyze fragmentation patterns to classify cancer types, dramatically expanding the potential capabilities of existing clinically used panels at minimal additional cost.


Subject(s)
Cell-Free Nucleic Acids , Circulating Tumor DNA , Prostatic Neoplasms , Male , Humans , Circulating Tumor DNA/genetics , Mutation , Prostatic Neoplasms/genetics , Cell-Free Nucleic Acids/genetics , Gene Expression Profiling , Biomarkers, Tumor/genetics
7.
Plant Foods Hum Nutr ; 78(2): 439-444, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37351712

ABSTRACT

Mung bean is a kind of legume commonly eaten by human. In the present study, a HPLC method for analyzing of two C-glycoside flavonoids, isovitexin and vitexin, in Mung bean was developed. Results showed that the flavonoids are mainly existed in Mung bean coat (MBC), while kernel contains very trace. The extraction of C-glycoside flavonoids from MBC was optimized. MBC extracts with isovitexin and vitexin contents of 29.0 ± 0.28% and 35.8 ± 0.19% were obtained with yield of 1.6 ± 0.21%. MBC extracts exhibited inhibitory activities on pancreatic lipase and α-glucosidase with IC50 values of 0.147 mg/ml and 0.226 mg/ml, respectively. The inhibitory kinetics revealed that MBC extracts showed mixed-type inhibition on these enzymes. Fluorescence quenching titration confirmed the binding of MBC extracts with the enzyme proteins. In vivo study revealed that pre-administration with MBC extracts significantly reduced the triglyceride absorption. Furthermore, it also improved postprandial hyperglycemia in rats through the inhibition of α-glucosidase.


Subject(s)
Fabaceae , Vigna , Rats , Humans , Animals , Flavonoids/pharmacology , Flavonoids/chemistry , Lipase , alpha-Glucosidases/metabolism , Vigna/metabolism , Glycoside Hydrolase Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Fabaceae/chemistry
8.
N Biotechnol ; 76: 72-81, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37182820

ABSTRACT

The development of bacterial cellulose (BC) industrialization has been seriously affected by its production. Mannose/mannan is an essential component in many biomass resources, but Komagataeibacter xylinus uses mannose in an ineffective way, resulting in waste. The aim of this study was to construct recombinant bacteria to use mannose-rich biomass efficiently as an alternative and inexpensive carbon source in place of the more commonly used glucose. This strategy aimed at modification of the mannose catabolic pathway via genetic engineering of K. xylinus ATCC 23770 strain through expression of mannose kinase and phosphomannose isomerase genes from the Escherichia coli K-12 strain. Recombinant and wild-type strains were cultured under conditions of glucose and mannose respectively as sole carbon sources. The fermentation process and physicochemical properties of BC were investigated in detail in the strains cultured in mannose media. The comparison showed that with mannose as the sole carbon source, the BC yield from the recombinant strain increased by 84%, and its tensile strength and elongation were increased 1.7 fold, while Young's modulus was increased 1.3 fold. The results demonstrated a successful improvement in BC yield and properties on mannose-based medium compared with the wild-type strain. Thus, the strategy of modifying the mannose catabolic pathway of K. xylinus is feasible and has significant potential in reducing the production costs for industrial production of BC from mannose-rich biomass.


Subject(s)
Escherichia coli K12 , Gluconacetobacter xylinus , Mannose/metabolism , Cellulose/chemistry , Escherichia coli K12/metabolism , Gluconacetobacter xylinus/genetics , Gluconacetobacter xylinus/metabolism , Glucose/metabolism , Carbon/metabolism
9.
Ann Oncol ; 34(7): 605-614, 2023 07.
Article in English | MEDLINE | ID: mdl-37164128

ABSTRACT

BACKGROUND: Metastatic castration-sensitive prostate cancer (mCSPC) is commonly classified into high- and low-volume subgroups which have demonstrated differential biology, prognosis, and response to therapy. Timing of metastasis has similarly demonstrated differences in clinical outcomes; however, less is known about any underlying biologic differences between these disease states. Herein, we aim to compare transcriptomic differences between synchronous and metachronous mCSPC and identify any differential responses to therapy. PATIENTS AND METHODS: We performed an international multi-institutional retrospective review of men with mCSPC who completed RNA expression profiling evaluation of their primary tumor. Patients were stratified according to disease timing (synchronous versus metachronous). The primary endpoint was to identify differences in transcriptomic profiles between disease timing. The median transcriptomic scores between groups were compared with the Mann-Whitney U test. Secondary analyses included determining clinical and transcriptomic variables associated with overall survival (OS) from the time of metastasis. Survival analysis was carried out with the Kaplan-Meier method and multivariable Cox regression. RESULTS: A total of 252 patients were included with a median follow-up of 39.6 months. Patients with synchronous disease experienced worse 5-year OS (39% versus 79%; P < 0.01) and demonstrated lower median androgen receptor (AR) activity (11.78 versus 12.64; P < 0.01) and hallmark androgen response (HAR; 3.15 versus 3.32; P < 0.01). Multivariable Cox regression identified only high-volume disease [hazard ratio (HR) = 4.97, 95% confidence interval (CI) 2.71-9.10; P < 0.01] and HAR score (HR = 0.51, 95% CI 0.28-0.88; P = 0.02) significantly associated with OS. Finally, patients with synchronous (HR = 0.47, 95% CI 0.30-0.72; P < 0.01) but not metachronous (HR = 1.37, 95% CI 0.50-3.92; P = 0.56) disease were found to have better OS with AR and non-AR combination therapy as compared with monotherapy (P value for interaction = 0.05). CONCLUSIONS: We have demonstrated a potential biologic difference between metastatic timing of mCSPC. Specifically, for patients with low-volume disease, those with metachronous low-volume disease have a more hormone-dependent transcriptional profile and exhibit a better prognosis than synchronous low-volume disease.


Subject(s)
Biological Products , Prostatic Neoplasms, Castration-Resistant , Prostatic Neoplasms , Male , Humans , Transcriptome , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prognosis , Castration , Biological Products/therapeutic use , Prostatic Neoplasms, Castration-Resistant/drug therapy , Androgen Antagonists/therapeutic use
10.
J Endocrinol Invest ; 46(9): 1843-1854, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37020103

ABSTRACT

OBJECTIVE: Silent corticotroph adenomas (SCAs) are a subtype of nonfunctioning pituitary adenomas that exhibit more aggressive behavior. However, rapid and accurate preoperative diagnostic methods are currently lacking. DESIGN: The purpose of this study was to examine the differences between SCA and non-SCA features and to establish radiomics models and a clinical scale for rapid and accurate prediction. METHODS: A total of 260 patients (72 SCAs vs. 188 NSCAs) with nonfunctioning adenomas from Peking Union Medical College Hospital were enrolled in the study as the internal dataset. Thirty-five patients (6 SCAs vs. 29 NSCAs) from Fuzhou General Hospital were enrolled as the external dataset. Radiomics models and an SCA scale to preoperatively diagnose SCAs were established based on MR images and clinical features. RESULTS: There were more female patients (internal dataset: p < 0.001; external dataset: p = 0.028) and more multiple microcystic changes (internal dataset: p < 0.001; external dataset: p = 0.012) in the SCA group. MRI showed more invasiveness (higher Knosp grades, p ≤ 0.001). The radiomics model achieved AUCs of 0.931 and 0.937 in the internal and external datasets, respectively. The clinical scale achieved an AUC of 0.877 and a sensitivity of 0.952 in the internal dataset and an AUC of 0.899 and a sensitivity of 1.0 in the external dataset. CONCLUSIONS: Based on clinical information and imaging characteristics, the constructed radiomics model achieved high preoperative diagnostic ability. The SCA scale achieved the purpose of rapidity and practicality while ensuring sensitivity, which is conducive to simplifying clinical work.


Subject(s)
ACTH-Secreting Pituitary Adenoma , Adenoma , Pituitary Neoplasms , Humans , Female , ACTH-Secreting Pituitary Adenoma/surgery , Adenoma/diagnostic imaging , Adenoma/surgery , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery , Magnetic Resonance Imaging , Retrospective Studies
11.
Clin Radiol ; 78(5): e359-e367, 2023 05.
Article in English | MEDLINE | ID: mdl-36858926

ABSTRACT

AIM: To investigate the value of a radiomics nomogram integrating intratumoural and peritumoural features in predicting lymph node metastasis and overall survival (OS) in patients with clinical stage IA non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: This study retrospectively enrolled 199 patients (training cohort: 71 patients from Affiliated Tumour Hospital of Nantong University; internal validation cohort: 46 patients from Affiliated Tumour Hospital of Nantong University; external validation cohort: 82 patients from the public database). CT radiomics models were constructed based on four volumes of interest: gross tumour volume (GTV), gross and 3 mm peritumoural volume (GPTV3), gross and 6 mm peritumoural volume (GPTV6), and gross and 9 mm peritumoural volume (GPTV9). The optimal radiomics signature was further combined with independent clinical predictors to develop a nomogram. Univariable and multivariable Cox regression analysis were applied to determine the relationship between factors and OS. RESULTS: GPTV6 radiomics yielded better performance than GTV, GPTV3, and, GPTV9 radiomics in the training (area under the curve [AUC], 0.81), internal validation (AUC, 0.79), and external validation cohorts (AUC, 0.71), respectively. The nomogram integrating GPTV6 radiomics and spiculation improved predictive ability, with AUCs of 0.85, 0.80, and 0.74 in three cohorts, respectively. Pathological lymph node metastasis, nomogram-predicted lymph node metastasis, and pleural indentation were independent risk predictors of OS (p<0.05). CONCLUSIONS: The nomogram integrating GPTV6 radiomics features and independent clinical predictors performed well in predicting lymph node metastasis and prognosis in patients with clinical stage IA NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Nomograms , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Retrospective Studies , Lymphatic Metastasis/diagnostic imaging , Lung Neoplasms/diagnostic imaging , Lymph Nodes , Prognosis
12.
Int J Biol Macromol ; 239: 124221, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36990400

ABSTRACT

Size and properties of tubular bacterial nanocellulose (BNC) can be regulated by controllable mercerization with thinner tube walls, better mechanical properties, and improved biocompatibility. Although mercerized BNC (MBNC) conduits have considerable potential as small-caliber vascular grafts (<6 mm), poor suture retention and lack of compliance that cannot match natural blood vessels increase the difficulty of surgery and limit potential clinical application. Polyvinyl alcohol (PVA) is a kind of hydrophilic polymer with good biocompatibility and elasticity, which can precipitate in alkaline solutions. In this study, novel elastic mercerized BNC/PVA conduits (MBP) are manufactured combining mercerization of BNC tubes with precipitation and phase separation of PVA with thinner tube wall, improved suture retention, better elasticity, good hemocompatibility and great cytocompatibility. The MBP obtained with 12.5 % PVA is selected for transplantation in a rat abdominal aorta model. For 32 weeks, normal blood flow is observed using Doppler sonographic inspection, which demonstrates long-term patency. Immunofluorescence staining results also indicate the formation of endothelium and smooth muscle layers. The results indicate the introduction of PVA, and its phase separation into mercerization of tubular BNC can endow MBP conduits with better compliance and suture retention, making it a promising candidate for blood vessel replacement.


Subject(s)
Bioprosthesis , Polyvinyl Alcohol , Animals , Rats , Blood Vessel Prosthesis
13.
Carbohydr Polym ; 306: 120572, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36746593

ABSTRACT

Therapeutic benefits of small caliber artificial blood vessels to cure cardio and cerebrovascular diseases are mainly limited by their low patency during long-term transplantation. Bacterial nanocellulose (BNC), as a natural polysaccharide mainly synthesized by a bacterium Komagataeibatacter xylinus, has shown great potential in small-caliber vascular graft applications due to its shape controllability, and furthermore its physical surface structure can be adjusted with different treatments. However, influences of physical surface structure and properties of BNC conduits on behaviors of vascular cells have not been investigated. In this work, mercerized BNC conduits (MBNC) with different surface roughness and stiffness were constructed by controlled alkali (NaOH) treatment. The changes of surface structures and properties significantly affected the behaviors of vascular cells and gene expression; meanwhile, the cell seeding density also affected the cell responses. After mercerization with NaOH concentration > 10 %, it was observed that the increased stiffness of MBNC decreased several functional gene expressions of human vascular endothelial cells, and the pathological transformation of smooth muscle cells was inhibited. This study demonstrates physical surface structure of MBNC conduits will critically regulate functions and behaviors of vascular cells and it also provides important designing parameters to improve the long-term patency of BNC-based conduits.


Subject(s)
Blood Substitutes , Humans , Cellulose/chemistry , Endothelial Cells , Sodium Hydroxide , Prostheses and Implants
14.
Ground Water ; 61(2): 224-236, 2023 03.
Article in English | MEDLINE | ID: mdl-34859432

ABSTRACT

A thorough assessment of thermal properties in heterogeneous subsurface is necessary in design of low-temperature borehole heat exchangers (BHEs). A distributed thermal response test (DTRT), which combines distributed temperature sensing (DTS) with a conventional thermal response test (TRT), was conducted in a U-bend geothermal loop installed in an open borehole at the University of Illinois at Urbana-Champaign to estimate thermal properties by analyzing the thermal response of different geologic materials while applying a constant heat input rate. Fiber-optic cables in the DTRT were deployed both inside the U-bend geothermal loop and in the center of the borehole to improve the accuracy of calculated heat-loss rates and borehole temperature profile measurements. To assess the subsurface thermal conductivity during the heating phase of the DTRT, a single-source model and a multi-source model, both based on the infinite line source method, were developed using the borehole temperature data and temperatures inside and along the outside of the loop, separately. The two models returned similar thermal conductivity values. The multi-source modeling has the advantage of predicting the thermal conductivity of heterogeneous geologic materials from borehole temperature profiles during the DTRT heating phase. In addition, based on the distributed thermal conductivity measured in the borehole, estimates were made for both radial thermal impacts and the rate of heat loss in the BHE.


Subject(s)
Groundwater , Temperature , Hot Temperature , Geology
15.
Ground Water ; 61(2): 237-244, 2023 03.
Article in English | MEDLINE | ID: mdl-34913479

ABSTRACT

We present a novel integrated two-region model that couples simulation of local heat transfer processes in borehole heat exchangers (BHEs) with field-scale heat transport simulation using MT3DMS to fulfill the dynamic simulation of the borehole geothermal systems. This includes the prediction of subsurface thermal perturbation induced by BHEs, derivation of the U-pipe circulating fluid temperature profile within boreholes, and the evaluation of the ground source heat pump efficiency based on available time series of building heat load. In our approach, MT3DMS is the simulator for the two-dimensional field-scale heat transport, while new Python modules are developed to analytically solve the thermal transfer process within boreholes and interface iteratively with MT3DMS. A Python package for scripting MODFLOW-based code named Flopy is used to establish the MT3DMS numerical model. The proposed model is validated against analytical solutions and we demonstrate the application to more complex test problems with field-scale heterogeneity and pumping. Instructions are provided to access the source code and example problems which are available online.


Subject(s)
Groundwater , Hot Temperature , Models, Theoretical , Computer Simulation , Temperature
16.
Biomacromolecules ; 24(1): 201-212, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36441906

ABSTRACT

The treatment for corneal damage requires donor corneal transplantation, but there is a serious scarcity of donor corneas worldwide. In this study, we aimed to design a new artificial cornea with good cytocompatibility, excellent optical properties and suture resistance, and great moisturizing properties. A new bacterial nanocellulose (BNC) membrane with anisotropic mechanical properties and high light transmission was produced in a horizontal rotary drum reactor. However, as a potential material for artificial keratoplasty, the transparency and mechanical properties of the new BNC membrane were not satisfactory. Thus, hyaluronic acid (HA) was introduced in the BNC to synthesize the BNC/HA composite membrane by using 1,4-butanediol diglycidyl ether (BDDE) as the chemical cross-linking agent. The micro-morphology, light transmittance, mechanical properties, water content, moisture retention ability, and cytocompatibility of the composite membranes were further evaluated. HA was fixed in the BNC network by the ether bond, and the composite membrane was found to have excellent light transmittance (up to 95.96%). The composite membrane showed excellent mechanical properties, for instance, its tensile strength exceeded the human normal intraocular pressure (IOP) (1.33-2.80 kPa), the maximum burst pressure was about 130 kPa, 46-97 times that of the normal IOP, and its suture force was close to that of the human amniotic membrane (0.1 N). Based on the three-dimensional network scaffold of BNC and the high water absorption characteristics of HA, the artificial cornea had high water content and high moisture retention ability. The rabbit corneal stromal cells cultured in vitro showed that the artificial cornea substitute had excellent cytocompatibility. BDDE is the most frequently used cross-linker in most HA products in the current cosmetic medicine industry owing to its long-term safety records for over 15 years. Therefore, the BNC/HA composite hydrogel cross-linked with BDDE has great potential in artificial keratoplasty or ocular surface repair.


Subject(s)
Corneal Transplantation , Hyaluronic Acid , Animals , Humans , Rabbits , Hyaluronic Acid/chemistry , Cornea , Prostheses and Implants , Hydrogels/chemistry , Butylene Glycols/chemistry
17.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(11): 857-860, 2022 Nov 20.
Article in Chinese | MEDLINE | ID: mdl-36510723

ABSTRACT

Objective: To establish a purge and trap-gas chromatography-mass spectrometry method based on soil analysis model for the determination of six benzene homologues (benzene, toluene, ethylbenzene, m-xylene, p-xylene and o-xylene) in human blood. Methods: From September 2020 to May 2021, diatomite was used as a dispersant to add 2.0 ml blood sample and fully mixed. The sample was directly injected into the purging and collecting bottle after purging. The gas chromatography column was used for separation. The retention time locking was used for qualitative analysis and the selected ion scanning mode (SIM) was used for detection. The detection limit and recovery rate of the method were analyzed. Results: The linear range of the method for the determination of six benzene homologues in human blood was 0.02-10.00 ng/ml, the correlation coefficient was 0.9927-0.9968, the detection limit was 0.006-0.016 ng/ml, the recovery rate of sample spiking was 84.39%-102.41%, and the precision of the method was 3.06%-6.90%. Conclusion: Purge and trap-gas chromatography-mass spectrometry can simultaneously determine the contents of six benzene homologues in human blood. The pretreatment method is simple, time-saving, and the method has low detection limit, which provides a scientific basis for the detection of benzene homologues in human body.


Subject(s)
Benzene , Xylenes , Humans , Benzene/analysis , Gas Chromatography-Mass Spectrometry/methods , Xylenes/analysis , Benzene Derivatives/analysis , Toluene/analysis
18.
Zhonghua Zhong Liu Za Zhi ; 44(10): 1139-1145, 2022 Oct 23.
Article in Chinese | MEDLINE | ID: mdl-36319461

ABSTRACT

Objective: To investigate the impact of lung metastases on the prognosis of patients with gestational trophoblastic neoplasia (GTN). Methods: Patients with International Federation of Gynaecology and Obstetrics (FIGO) stage Ⅰ-Ⅲ GTN receiving primary chemotherapy in Peking Union Medical College Hospital between July 2014 and December 2018 were retrospectively analyzed and divided into group 1 with lung metastasis and group 2 without lung metastasis. The baseline characteristics and treatment outcomes of the two groups were compared. The optimal cut-off values of the diameter of largest lung nodule associated with recurrence were identified by receiver operating characteristic (ROC) curves. Logistic regression analyses were performed to identify risk factors for prognosis. Survival analysis was performed by Kaplan-Meier method and Log rank test. Results: Of the 381 GTN patients enrolled (216 with lung metastases and 165 without lung metastases), the pretreatment ß human chorionic gonadotrophin [median: 12 572 IU/L (1 832-51 594 IU/L) vs. 5 614 IU/L (559-26 140 IU/L), P=0.001] and FIGO score [median: 3 (1-6) vs. 2 (1-4), P=0.038] were significantly higher in patients with lung metastases than those without lung metastases. In patients with FIGO score≥5, the emergence of resistance (26.76% vs. 10.26%, P=0.036) and median number of chemotherapy courses to achieve complete remission [6 (6-8) vs. 5 (4-6), P<0.001] were significantly higher than patients with lung metastases. In patients with FIGO score 0-4, no significant difference was found in the treatment outcomes between the two groups(P=0.833). Among all patients with lung metastases, the ROC curve showed a sensitivity and specificity of 62.5% and 78.8%, respectively, for predicting recurrence when the length of the largest lung nodule was 1.6 cm, with an area under the curve (AUC) of 0.711 (95% CI: 0.550, 0.871, P=0.044). Multivariate logistic regression analysis suggested a significantly higher recurrence rate when the largest lung nodule was ≥1.6 cm (OR=7.394, 95% CI: 1.003, 54.520, P=0.049). The 1-year disease-free survival rate was significantly lower in patients with the largest lung nodule ≥1.6 cm than in patients with the nodule <1.6 cm (98.2% vs. 82.4%, P=0.001). Conclusions: Lung metastasis is associated with increased first-line chemotherapy resistance in patients with FIGO scores≥5. The diameter of the largest lung metastatic nodule ≥1.6 cm is an effective factor for predicting recurrence.


Subject(s)
Gestational Trophoblastic Disease , Lung Neoplasms , Pregnancy , Female , Humans , Retrospective Studies , Gestational Trophoblastic Disease/drug therapy , Gestational Trophoblastic Disease/pathology , Prognosis , Lung Neoplasms/drug therapy , Disease-Free Survival , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
19.
Polymers (Basel) ; 14(20)2022 Oct 17.
Article in English | MEDLINE | ID: mdl-36297946

ABSTRACT

Bacterial nanocellulose (BNC) has received great attention for application as an artificial blood vessel material. However, many results showed that pristine BNC could not perfectly meet all the demands of blood vessels, especially for rapid endothelialization. In order to improve the properties of small-caliber vessels, different concentrations of fish gelatin (Gel) were deposited into the 3D network tubes and their properties were explored. The BNC/Gel composite tubes were treated with glutaraldehyde to crosslink BNC and fish gelatin. Compared with pristine BNC tubes, the BNC/Gel tubes had a certain improvement in mechanical properties. In vitro cell culture demonstrated that the human endothelial cells (HUVECs) and human smooth muscle cells (HSMCs) planted on the internal walls of BNC/Gel tubes showed better adhesion, higher proliferation and differentiation potential, and a better anticoagulation property, as compared to the cells cultured on pristine BNC tubes. Whole-blood coagulation experiments showed that the BNC/Gel tube had better properties than the BNC tube, and the hemolysis rate of all samples was less than 1.0%, satisfying the international standards for medical materials. An increase in the content of fish gelatin also increased the mechanical properties and the biocompatibility of small-caliber vessels. Considering the properties of BNC/Gel tubes, 1.0 wt/v% was selected as the most appropriate concentration of fish gelatin for a composite.

20.
Carbohydr Polym ; 296: 119917, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36087973

ABSTRACT

Low-temperature two-step concentrated H2SO4 was discovered to be a solvent with high cellulose solubility [>300 g/L (17 wt%)], fast cellulose dissolution, high regeneration yield (>0.92 g/g), and cellulose being mouldable during regeneration. The superior performance was enabled by the much better compatibility of cellulose with lower concentrated H2SO4 at low temperature, compared with that of high concentrated H2SO4. The regenerated cellulose was characterized by mostly unchanged composition and highly tunable degree of polymerization (DP). The H2SO4 starting content, cotton fibre temperature, dissolution temperature, regeneration temperature, regeneration bath and storage time were factors determining the DP of regenerated cellulose, which could be equivalent to 4-90 % of the original cotton. These advantages of the solvent enabled versatile application in fabrication of extra strong cellulose hydrogels, manufacture of strong cellulose fibres, preparation of various homogenous composites which would be prepared with much more difficulty by using other solvents, and facile manufacture of cellooligosaccharides.


Subject(s)
Cellulose , Cellulose/chemistry , Polymerization , Solubility , Solvents/chemistry , Temperature
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