Obliteration of portal venules contributes to portal hypertension in biliary cirrhosis.

The effects of the obliteration of portal venules (OPV) in cirrhotic portal hypertension are poorly understood. To investigate its contribution to portal hypertension in biliary cirrhosis and its underlying mechanism, we evaluated OPV using two-dimensional (2D) histopathology in liver explants from patients with biliary atresia (BA, n = 63), primary biliary cholangitis (PBC, n = 18), and hepatitis B-related cirrhosis (Hep-B-cirrhosis, n = 35). Then, three-dimensional (3D) OPV was measured by X-ray phase-contrast CT in two parallel models in rats following bile duct ligation (BDL) or carbon tetrachloride (CCl4) administration, representing biliary cirrhosis and post-necrotic cirrhosis, respectively. The portal pressure was also measured in the two models. Finally, the effects of proliferative bile ducts on OPV were investigated. We found that OPV was significantly more frequent in patients with biliary cirrhosis, including BA (78.57 ± 16.45%) and PBC (60.00 ± 17.15%), than that in Hep-B-cirrhotic patients (29.43 ± 14.94%, p < 0.001). OPV occurred earlier, evidenced by the paired liver biopsy at a Kasai procedure (KP), and was irreversible even after a successful KP in the patients with BA. OPV was also significantly more frequent in the BDL models than in the CCl4 models, as shown by 2D and 3D quantitative analysis. Portal pressure was significantly higher in the BDL model than that in the CCl4 model. With the proliferation of bile ducts, portal venules were compressed and irreversibly occluded, contributing to the earlier and higher portal pressure in biliary cirrhosis. OPV, as a pre-sinusoidal component, plays a key role in the pathogenesis of portal hypertension in biliary cirrhosis. The proliferated bile ducts and ductules gradually take up the 'territory' originally attributed to portal venules and compress the portal venules, which may lead to OPV in biliary cirrhosis. © 2024 The Pathological Society of Great Britain and Ireland.

In situ growth of imine-based covalent organic framework as stationary phase for open-tubular capillary electrochromatographic separation.

Designing advanced stationary phases to improve separation efficiency is essential in capillary electrochromatography. Due to their outstanding performance, covalent organic frameworks have recently demonstrated considerable promise in the field of separation science. Herein, an open-tubular capillary electrochromatography method was reported using porous imine-based covalent organic framework with sufficiently available interaction sites as stationary phase. The imine-based covalent organic framework coated capillary was easily prepared via an in situ growth method at room temperature, and its separation performance was evaluated, indicating the high separation efficiency for three types of analytes, including herbicides, polybrominated dibenzofurans, and bisphenols. Moreover, the imine-based covalent organic framework coated capillary showed good reproducibility and stability, with intraday (n = 3), interday (n = 3), and column-to-column (n = 3) relative standard deviations of retention time and peak areas of less than 5%. The separation efficiency of the coated capillary remained unchanged even after 200 runs and the maximum theoretical plates reached up to 85 595 N/m for 4,4'-ethylidenebisphenol. It was predicted that the imine-based covalent organic framework stationary phase would be a strong contender for chromatographic separation with high efficiency.

Insight into microvascular adaptive alterations in the Glisson system of biliary atresia after Kasai portoenterostomy using X-ray phase-contrast CT.

OBJECTIVES: To investigate microvascular alterations in the Glisson system of biliary atresia (BA) patients after Kasai portoenterostomy (KP) using three-dimensional (3D) virtual histopathology based on X-ray phase-contrast CT (PCCT). METHODS: Liver explants from BA patients were imaged using PCCT, and 32 subjects were included and divided into two groups: KP (n = 16) and non-KP (n = 16). Combined with histological analysis and 3D visualization technology, 3D virtual histopathological assessment of the biliary, arterial, and portal venous systems was performed. According to loop volume ratio, 3D spatial density, relative surface area, tortuosity, and other parameters, pathological changes of microvasculature in the Glisson system were investigated. RESULTS: In the non-KP group, bile ducts mostly manifested as radial multifurcated hyperplasia and twisted into loops. In the KP group, the bile duct hyperplasia was less, and the loop volume ratio of bile ducts decreased by 13.89%. Simultaneously, the arterial and portal venous systems presented adaptive alterations in response to degrees of bile duct hyperplasia. Compared with the non-KP group, the 3D spatial density of arteries in the KP group decreased by 3.53%, and the relative surface area decreased from 0.088 ± 0.035 to 0.039 ± 0.015 (p < .01). Deformed portal branches gradually recovered after KP, with a 2.93% increase in 3D spatial density and a decrease in tortuosity from 1.17 ± 0.06 to 1.14 ± 0.04 (p < .01) compared to the non-KP group. CONCLUSION: 3D virtual histopathology via PCCT clearly reveals the microvascular structures in the Glisson system of BA patients and provides key insights into the morphological mechanism of microvascular adaptation induced by biliary tract dredging after KP in BA disease. KEY POINTS: • 3D virtual histopathology via X-ray phase-contrast computed tomography clearly presented the morphological structures and pathological changes of microvasculature in the Glisson system of biliary atresia patients. • The morphological alterations of microvasculature in the Glisson system followed the competitive occupancy mechanism in the process of biliary atresia.

Genome-Wide Identification of the MAPK and MAPKK Gene Families in Response to Cold Stress in Prunus mume.

Protein kinases of the MAPK cascade family (MAPKKK-MAPKK-MAPK) play an essential role in plant stress response and hormone signal transduction. However, their role in the cold hardiness of Prunus mume (Mei), a class of ornamental woody plant, remains unclear. In this study, we use bioinformatic approaches to assess and analyze two related protein kinase families, namely, MAP kinases (MPKs) and MAPK kinases (MKKs), in wild P. mume and its variety P. mume var. tortuosa. We identify 11 PmMPK and 7 PmMKK genes in the former species and 12 PmvMPK and 7 PmvMKK genes in the latter species, and we investigate whether and how these gene families contribute to cold stress responses. Members of the MPK and MKK gene families located on seven and four chromosomes of both species are free of tandem duplication. Four, three, and one segment duplication events are exhibited in PmMPK, PmvMPK, and PmMKK, respectively, suggesting that segment duplications play an essential role in the expansion and evolution of P. mume and its gene variety. Moreover, synteny analysis suggests that most MPK and MKK genes have similar origins and involved similar evolutionary processes in P. mume and its variety. A cis-acting regulatory element analysis shows that MPK and MKK genes may function in P. mume and its variety's development, modulating processes such as light response, anaerobic induction, and abscisic acid response as well as responses to a variety of stresses, such as low temperature and drought. Most PmMPKs and PmMKKs exhibited tissue-specifific expression patterns, as well as time-specific expression patterns that protect them through cold. In a low-temperature treatment experiment with the cold-tolerant cultivar P. mume 'Songchun' and the cold-sensitive cultivar 'Lve', we find that almost all PmMPK and PmMKK genes, especially PmMPK3/5/6/20 and PmMKK2/3/6, dramatically respond to cold stress as treatment duration increases. This study introduces the possibility that these family members contribute to P. mume's cold stress response. Further investigation is warranted to understand the mechanistic functions of MAPK and MAPKK proteins in P. mume development and response to cold stress.

Efficiency comparison with fovea-sparing internal limiting membrane peeling and complete internal limiting membrane peeling for treating myopic traction maculopathy.

PURPOSE: To explore whether the efficacy of fovea-sparing internal limiting membrane peeling (FS-ILMP) is better than that of complete internal limiting membrane peeling (ILMP). METHODS: This retrospective clinical study included 34 cases (34 eyes) with myopic traction maculopathy collected from June 2017 to February 2019. Twenty-three-gauge (23-G) pars plana vitrectomy (23G PPV) was performed on all patients. In the FS-ILMP group, 18 eyes retained the internal limiting membrane (ILM) of about 1 to 1.5 papillary diameter centered on fovea centralis, while in the standard ILMP group, the ILM was completely removed from 16 eyes. The best corrected visual acuity (BCVA), central foveal thickness (CFT), and other indexes were collected before and 6 months after surgery. RESULTS: There was no significant difference in baseline clinical characteristics between the two groups. CFT and BCVA were significantly improved in both FS-ILMP and standard ILMP group, but the postoperative BCVA of the FS-ILMP group was significantly better than that of the standard ILMP group (P < 0.001). Two cases of subretinal effusion in macula were recorded in the FS-ILMP group, and three eyes in the standard ILMP group developed macular holes after surgery. Although both treatments relieved the mechanical traction of macular fovea, the patients in the FS-ILMP group showed better clinical outcomes in various aspects. CONCLUSION: These results improved our understanding of the clinical application of vitrectomy combined with preservation of ILM upon the fovea centralis, which might lay a foundation for in-depth study on the treatment of myopic traction maculopathy.

Insight into Bile Duct Reaction to Obstruction from a Three-dimensional Perspective Using ex Vivo Phase-Contrast CT.

Background Biliary obstruction leads to an increase in biliary pressure within the biliary system, which induces the morphologic adaptation of the biliary tree. Purpose To observe and to quantify the morphologic characteristics of the adaptation in a bile duct ligation rat model and verify it in patients with biliary atresia in a three-dimensional (3D) manner using x-ray phase-contrast CT. Materials and Methods A bile duct ligation model was induced in 40 male Sprague-Dawley rats, which were divided into five groups: the control group (no ligation) and groups 2, 4, 6, and 8 weeks after bile duct ligation (eight animals in each group). Liver tissue samples (approximately 1.8 cm in length and 1.3 cm in height) were imaged by using phase-contrast CT and compared with histologic analysis. With a combination of phase-contrast CT and 3D visualization technology, the entire biliary system and the intrahepatic vascular system were quantitatively analyzed according to downstream, midstream, and upstream domains based on bile duct volume, surface area, and other parameters. Additionally, liver explant tissues from 28 patients with biliary atresia were studied to determine the impact of biliary tract reconstruction. Results To offset the increased biliary pressure within the biliary system, the ductular reaction in the downstream, midstream, and upstream domains manifested as dilatation, spiderweb-like looping, and interconnected honeycomb-like patterns, respectively. The most severe ductular reaction occurred in the upstream domain, and the relative surface area (mean, 0.02 µm-1 ± 0.01, 0.04 µm-1 ± 0.01, 0.07 µm-1 ± 0.02, and 0.10 µm-1 ± 0.02 for the 2-8-week groups, respectively; P < .01 among the groups) and volume fraction of ductules (mean, 16.54% ± 4.62, 19.69% ± 6.41, 26.92% ± 5.82, and 38.34% ± 10.36 for the 2-8-week groups, respectively; P < .01 among the groups except between the 2- and 4-week groups [P = .062]) significantly increased over time. In patients with biliary atresia, it was observed that both fibrosis and proliferative ductules regressed after successful biliary tract reconstruction following Kasai portoenterostomy. Furthermore, ductular reaction was accompanied by a progressive increase in the arterial supply but a loss of portal blood supply. Conclusion X-ray phase-contrast CT with three-dimensional rendering of the biliary system in a bile duct ligation rat model provides key insights into ductular reaction or biliary self-adaptation triggered by increased biliary pressure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Vannier and Wang in this issue.

Dual-path deep learning reconstruction framework for propagation-based X-ray phase-contrast computed tomography with sparse-view projections.

Propagation-based X-ray phase-contrast computed tomography (PB-PCCT) can serve as an effective tool for studying organ function and pathologies. However, it usually suffers from a high radiation dose due to the long scan time. To alleviate this problem, we propose a deep learning reconstruction framework for PB-PCCT with sparse-view projections. The framework consists of dual-path deep neural networks, where the edge detection, edge guidance, and artifact removal models are incorporated into two subnetworks. It is worth noting that the framework has the ability to achieve excellent performance by exploiting the data-based knowledge of the sample material characteristics and the model-based knowledge of PB-PCCT. To evaluate the effectiveness and capability of the proposed framework, simulations and real experiments were performed. The results demonstrated that the proposed framework could significantly suppress streaking artifacts and produce high-contrast and high-resolution computed tomography images.

Comparison of microstructural imaging of the root canal isthmus using propagation-based X-ray phase-contrast and absorption micro-computed tomography.

Clear and complete microstructural imaging of the root canal isthmus is an important part of pathological investigations in research and clinical practice. X-ray micro-computed tomography (µCT) is a widely used non-destructive imaging technique, which allows for distortion-free three-dimensional (3D) visualisation. While absorption µCT typically has poor contrast resolution for observing the root canal isthmus, especially for weak-absorbing tissues, propagation-based X-ray phase-contrast imaging (PBI) is a powerful imaging method, which in its combination with µCT (PB-PCµCT) enables high-resolution and high-contrast microstructural imaging of the weak-absorbing tissues in samples. To investigate the feasibility and ability of PB-PCµCT in microstructural imaging of the root canal isthmus, conventional absorption µCT and PB-PCµCT experiments were performed. The two-dimensional (2D) and 3D comparison results demonstrated that, compared to absorption µCT, PB-PCµCT has the ability to image the root canal isthmus more clearly and completely, and thus, it has great potential to serve as a valuable tool for biomedical and preclinical studies on the root canal isthmus.

Pretarsal orbicularis oculi muscle tightening with skin flap excision in the treatment of lower eyelid involutional entropion.

BACKGROUND: To evaluate a modified technique for involutional entropion correction in a retrospective cohort study. METHODS: The patients with involutional entropion eyelid were corrected by tightening the pretarsal orbicularis oculi muscle and excising the excess skin of the lower eyelid. The patients received correction surgery from April 2013 to March 2019 were followed up for more than 6 months postoperatively. The outcome measures included the complications and the recurrence rates. RESULTS: Total 152 patients (169 eyes) were included. The mean follow-up period was 29.6 months (range: 6-36 months). Postoperative ectropion (over-correction) was observed in 1 patient with 1 eyelid (0.59%); yet, no further surgery was needed for this patient. Recurrence of entropion was found in 1 patient (0.59%). The patient with recurrent entropion received repeated surgery with the same method and achieved a good eyelid position. CONCLUSIONS: This study demonstrated that tightening the pretarsal orbicularis oculi muscle and excising the excess skin of the lower eyelid could be an effective surgical method to correct lower eyelid involutional entropion. This method is technically easy with a low recurrence rate and not associated with significant complications in Asians.

Chiral Fluorescent Silicon Nanoparticles for Aminopropanol Enantiomer: Fluorescence Discrimination and Mechanism Identification.

As an important chiral molecule for the preparation of levofloxacin, the optical purity of L-aminopropanol has a crucial effect on the pharmacology and pharmacodynamics of levofloxacin. Therefore, it is of great significance to discriminate D-aminopropanol and L-aminopropanol. In this paper, an effective aminopropanol enantiomer recognition method was established on the basis of the chiral fluorescent silicon nanoparticles (SiNPs) probe. The chiral fluorescent SiNPs were fabricated via a one-step aqueous solution synthesis strategy, which avoided multiple steps, pressurizing operation, and time-consuming postmodified procedures. Significantly, D-aminopropanol could significantly enhance the fluorescence of the chiral SiNPs, while L-aminopropanol could not affect the fluorescence of the chiral SiNPs. This could have occurred because of the stronger interaction between the chiral SiNPs and D-aminopropanol than that of L-aminopropanol. Thus, the rapid and selective recognition of the aminopropanol enantiomer was ideally realized. The mechanism of the chiral SiNPs recognizing aminopropanol was simulated by density functional theory quantum mechanical calculations. Interestingly, this was also proved by the separation of aminopropanol enantiomer using this chiral SiNPs-modified silica column in normal phase liquid chromatography. To the best of our knowledge, this is the first time that the chiral fluorescent SiNPs were synthesized and used to detect the aminopropanol enantiomer successfully. This work will inspire additional syntheses of chiral silicon nanomaterials and other nanomaterials with excellent properties and will enable application of chiral nanomaterials to other fields.

CPNE1 predicts poor prognosis and promotes tumorigenesis and radioresistance via the AKT singling pathway in triple-negative breast cancer.

Elevated expression of Copine 1 (CPNE1) has been observed in multiple cancers; however, the underlying mechanisms by which it affects cancer cells are unclear. We aimed to study the effect of CPNE1 on the tumorigenesis and radioresistance of triple-negative breast cancer (TNBC). Quantitative real-time polymerase chain reaction was used to detect the expression of CPNE1 in TNBC tissues and cell lines. Western blot, immunohistochemistry, and immunofluorescence were used to investigate the levels of CPNE1, p-AKT, AKT, cleaved caspase-3, cleaved PARP1, and γ-H2AX. Cell viability and apoptosis were measured by CCK-8 and flow cytometry, respectively. CPNE1 was overexpressed in TNBC tissues and cell lines and was associated with tumor size, distant metastases, and survival rates of patients with TNBC. Moreover, function study shows that CPNE1 promoted cell viability and inhibited cell apoptosis in vitro and inhibited the radiosensitivity of TNBC. Importantly, inactivation of AKT signaling inhibited the tumorigenesis and radioresistance mediated by CPNE1 in TNBC cells. In vivo xenograft study also shows that CPNE1 knockdown inhibited tumor growth and promoted cell apoptosis. Overall, our findings suggest that CPNE1 promotes tumorigenesis and radioresistance in TNBC by regulating AKT activation and targeted CPNE1 expression may be a strategy to sensitize TNBC cells toward radiation therapy.

In situ fabrication of 3D COF-300 in a capillary for separation of aromatic compounds by open-tubular capillary electrochromatography.

Two-dimensional (2D) COFs have been successfully applied for various applications, such as capillary electrochromatography (CEC). Compared with 2D COFs, three-dimensional (3D) COFs have higher surface area and lower density, which should have superior potential as the separation medium in CEC. However, the 3D COFs on the inner wall of capillary is hard to fabricate in situ. Up to date, the application of 3D COFs in open-tubular capillary electrochromatography (OT-CEC) is still considered a challenge. For the first time the COF-300-coated capillary was prepared by in situ growth (COF-300 was made from terephthalaldehyde and tetra-(4-anilyl)-methane) on OT-CEC. Benzene, methylbenzene, styrene, ethylbenzene, naphthalene, 1-methylnaphthalene, and propylbenzene were used to evaluate the performance of the COF-300-coated capillary by OT-CEC. For three consecutive runs, the intraday relative standard deviations (RSDs) of migration time and peak areas were 0.1-0.4% and 2.5-8.3%, respectively. The interday RSDs of migration time and peak areas were 0.2-0.5% and 1.0-10.8%, respectively. Five groups of aromatic co mpounds were used to further study the separation mechanism, which indicated that hydrophobic interaction and size selection interaction are the main factors. It should be noted that the COF-300-coated capillary can be used for more than 140 runs with no observable changes of the separation efficiency. Graphical abstract The 3D COF-300-coated capillary was prepared by in situ growth for OT-CEC. Six groups of aromatic compounds were separated by 3D COF-300-coated capillary. Size selection and hydrophobic interaction affect the migration time of analytes.

Three-dimensional visualization of fibrous tissues in cirrhotic rats via X-ray phase-contrast computed tomography with iodine staining.

To accurately characterize cirrhosis, knowledge of the 3D fibrous structures is essential. Histology is the gold standard in cirrhosis screening, but it mainly provides structural information in 2D planes and destroys the 3D samples in the process. The aim of this study was to evaluate the potential of X-ray phase-contrast computed tomography (PCCT) with iodine staining for the 3D nondestructive visualization of internal structural details in entire cirrhotic livers with histopathologic correlation. In this study, cirrhotic livers induced by carbon tetrachloride (CCl4) in rats were imaged via PCCT and then histopathologically processed. Characteristics of the cirrhosis, i.e. abnormal nodules surrounded by annular fibrosis, were established and a 3D reconstruction of these structures was also performed via PCCT. Fibrosis area, septal width and nodular size were measured and the correlation for these quantitative measurements between PCCT and histopathologic findings was analyzed. The results showed that fibrous bands, small nodules and angio-architecture in cirrhosis were clearly presented in the PCCT images, with histopathologic findings as standard reference. In comparison with histopathology, PCCT was associated with a very close value for fibrosis area, septal width and nodular size. The quantitative measurements showed a strong correlation between PCCT and histopathology. Additionally, the 3D structures of fibrous bands and microvasculature were presented simultaneously. PCCT provides excellent results in the assessment of cirrhosis characteristics and 3D presentation of these feature structures compared with histopathology. Thus, the technique may serve as an adjunct nondestructive 3D modality for cirrhosis characterization.

A new in-line X-ray phase-contrast computed tomography reconstruction algorithm based on adaptive-weighted anisotropic TpV regularization for insufficient data.

In-line X-ray phase-contrast computed tomography (IL-PCCT) is a valuable tool for revealing the internal detailed structures in weakly absorbing objects (e.g. biological soft tissues), and has a great potential to become clinically applicable. However, the long scanning time for IL-PCCT will result in a high radiation dose to biological samples, and thus impede the wider use of IL-PCCT in clinical and biomedical imaging. To alleviate this problem, a new iterative CT reconstruction algorithm is presented that aims to decrease the radiation dose by reducing the projection views, while maintaining the high quality of reconstructed images. The proposed algorithm combines the adaptive-weighted anisotropic total p-variation (AwaTpV, 0 < p < 1) regularization technique with projection onto convex sets (POCS) strategy. Noteworthy, the AwaTpV regularization term not only contains the horizontal and vertical image gradients but also adds the diagonal image gradients in order to enforce the directional continuity in the gradient domain. To evaluate the effectiveness and ability of the proposed algorithm, experiments with a numerical phantom and synchrotron IL-PCCT were performed, respectively. The results demonstrated that the proposed algorithm had the ability to significantly reduce the artefacts caused by insufficient data and effectively preserved the edge details under noise-free and noisy conditions, and thus could be used as an effective approach to decrease the radiation dose for IL-PCCT.

Phase-contrast computed tomography: A correlation study between portal pressure and three dimensional microvasculature of ex vivo liver samples from carbon tetrachloride-induced liver fibrosis in rats.

OBJECTIVE: Microvascular changes in liver fibrosis are considered as an important pathophysiological characteristic. Now, there is a lack of high-resolution three-dimensional (3D) imaging methods for observing the microvasculature throughout the entire livers. This study aims to investigate the 3D microvascular changes in the whole fibrotic livers via X-ray phase-contrast computed tomography (PCCT) and explore the correlations between portal pressures and microvascular changes in liver fibrosis progression. METHODS: Twenty-three fibrotic rats were imaged ex vivo using PCCT. Morphological changes of the microvasculature were characterized using tortuosity, texture features of the vascular inner wall, fractal dimension (FD) and Murray's deviation (MD), and quantitative changes were evaluated by microvascular density (MVD). The degree of liver fibrosis was assessed by histochemistry, and the portal pressure of each rat was measured before euthanasia. RESULTS: Using PCCT, subtle vascular structures in fibrotic livers were revealed in the 3D modality, and the qualitative description and quantitative evaluation of microvascular changes showed important differences during the progression of liver fibrosis. Moreover, microvascular changes, including tortuosity, texture features of the vascular inner wall, MD and MVD, exhibited good correlations with the fibrosis area (R ≥ 0.729, P < 0.001) and portal pressure (R ≥ 0.715, P < 0.001) in the development of fibrosis. CONCLUSIONS: PCCT technique demonstrates outstanding potential for 3D visualization of microvasculature in liver fibrosis. Microvascular changes in fibrotic livers may serve as a new surrogate histopathological marker in evaluating portal pressures or prognosing portal hypertension.

In silico toxicity evaluation of dioxins using structure-activity relationship (SAR) and two-dimensional quantitative structure-activity relationship (2D-QSAR).

Prediction of pEC50 values of dioxins binding with the aryl hydrocarbon receptor (AhR) is of great significance for exploring how dioxins induce toxicity in human body and evaluating their environmental behaviors and risks. To reveal the factors that influence the toxicity of dioxins, provide more accurate mathematical models for predicting the pEC50 values of dioxins, and supplement the toxicity database of persistent organic pollutants, qualitative structure-activity relationship (SAR) and two-dimensional quantitative structure-activity relationship (2D-QSAR) were used in this study. The research objects in this study were 60 organic compounds with pEC50 values and 162 compounds without pEC50 values, which included polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo-p-dioxins (PCDDs), and polybrominated dibenzo-p-dioxins (PBDDs). The qualitative structure-activity relationship (SAR) was performed first and concluded that halogen substitutions at any of the 2, 3, 7, and 8 sites increased the pEC50 value of the compound. Moreover, two-dimensional quantitative structure-activity relationship (2D-QSAR) models were established by employing multiple linear regression (MLR) method and artificial neural network (ANN) algorithm to investigate the factors affecting the pEC50 values of dioxins molecules. MLR was used to establish the well-understood linear model and ANN was used to establish a more accurate non-linear model. Both models have good fitting, robustness, and predictive ability. Importantly, the ability of dioxins binding to AhR is mainly determined by molecular descriptors including E1m, SM09_AEA (dm), RDF065u, F05 [Cl-Cl], and Neoplastic-80. In addition, the pEC50 values of the 162 dioxins without toxicity data were predicted by MLR and ANN models, respectively.

An iterative image reconstruction algorithm combined with forward and backward diffusion filtering for in-line X-ray phase-contrast computed tomography.

In-line X-ray phase-contrast computed tomography (IL-PCCT) can reveal fine inner structures for low-Z materials (e.g. biological soft tissues), and shows high potential to become clinically applicable. Typically, IL-PCCT utilizes filtered back-projection (FBP) as the standard reconstruction algorithm. However, the FBP algorithm requires a large amount of projection data, and subsequently a large radiation dose is needed to reconstruct a high-quality image, which hampers its clinical application in IL-PCCT. In this study, an iterative reconstruction algorithm for IL-PCCT was proposed by combining the simultaneous algebraic reconstruction technique (SART) with eight-neighbour forward and backward (FAB8) diffusion filtering, and the reconstruction was performed using the Shepp-Logan phantom simulation and a real synchrotron IL-PCCT experiment. The results showed that the proposed algorithm was able to produce high-quality computed tomography images from few-view projections while improving the convergence rate of the computed tomography reconstruction, indicating that the proposed algorithm is an effective method of dose reduction for IL-PCCT.

Rapid and in-situ preparation COFs coated capillary by adsorption method for the separation and determination of phthalate ester using CEC.

As a novel class of stationary phase materials, covalent organic frameworks (COFs) have shown great promise in open-tubular capillary electrochromatography. However, the current preparation of COFs coating capillaries heavily relies on tedious and time-consuming covalent bond methods. In this work, a novel, simple and rapid adsorption method was developed for fabrication of TPB-DMTP COF (fabricated from 1,3,5-tris(4-aminophenyl)benzene (TPB) and 2,5-dimethoxyterephthalaldehyde (DMTP)) coated capillary. Due to the crystallization process of the COF is greatly shortened because pre-modification capillary does not require silane coupling agent, this method enables the rapid preparation of COFs-coated capillaries. The organic molecular building units only need 25 min to form a stable COFs coating on the inner wall of a capillary by this method. To our knowledge, this is the shortest method for preparing COFs coated capillary up to now. The performance of the TPB-DMTP COF coated capillary was evaluated by using phthalate esters as model analytes. The results demonstrated that the TPB-DMTP COF coated capillary has excellent repeatability and stability. The relative standard deviations (RSDs) of the analyte's retention time of intra-day, inter-day and column-to-column were in the range of 0.05 %-0.27 %, 0.31 %-0.63 % and 0.31 %-0.88 %, respectively. And, no significant changes were observed in separation efficiency and retention time after over 200 runs. Finally, the TPB-DMTP COF coated capillary was applied for the determination of phthalates in marketed plastic bag and the recovery ranged from 88.0 % to 114.0 %.

Chiral-induced covalent organic framework as novel chiral stationary phase for chiral separation using open-tubular capillary electrochromatography.

As a novel class of chiral stationary phase (CPS) material, chiral covalent organic frameworks (CCOFs) have already shown great promise in open-tubular capillary electrochromatography (OT-CEC) for chiral separation. The synthesis methods of CCOFs used in OT-CEC mainly include bottom-up, post modification and chiral induction. The CCOFs synthesized by bottom-up and post modification strategies already have lots of applications in capillary electrochromatography, however, the chiral-induced synthesized via an asymmetric catalytic strategy has not yet been reported for using as the chiral stationary phase (CPS) in OT-CEC or even in chromatographic separation. Herein, the chiral-induced COF (Λ)-TpPa-1 was synthesized by asymmetric catalytic synthesis and coated on the inner surface of a capillary by an in-situ growth strategy as the CPS for chiral drug separation. The baseline separation of six enantiomers was achieved within 14 min, with a high-resolution (Rs) range from 1.85 to 6.75. Moreover, the resolution and migration time of the capillary keep stable within 160 runs, showing its superior stability and repeatability. This research provides a new idea for the development and application of novel CPS materials in the field of capillary electrochromatography separation, also shows the new application of chiral induced COFs. Furthermore, the chiral-induced CCOFs can be easily applied to other chromatographic separation fields, exhibiting its extensive application value in chiral analysis separation.

Multiscale X-ray phase-contrast CT unveils the evolution of bile infarct in obstructive biliary disease.

Bile infarct is a pivotal characteristic of obstructive biliary disease, but its evolution during the disease progression remains unclear. Our objective, therefore, is to explore morphological alterations of the bile infarct in the disease course by means of multiscale X-ray phase-contrast CT. Bile duct ligation is performed in mice to mimic the obstructive biliary disease. Intact liver lobes of the mice are scanned by phase-contrast CT at various resolution scales. Phase-contrast CT clearly presents three-dimensional (3D) images of the bile infarcts down to the submicron level with good correlation with histological images. The CT data illustrates that the infarct first appears on day 1 post-BDL, while a microchannel between the infarct and hepatic sinusoids is identified, the number of which increases with the disease progression. A 3D model of hepatic acinus is proposed, in which the infarct starts around the portal veins (zone I) and gradually progresses towards the central veins (zone III) during the disease process. Multiscale phase-contrast CT offers the comprehensive analysis of the evolutionary features of the bile infarct in obstructive biliary disease. During the course of the disease, the bile infarcts develop infarct-sinusoidal microchannels and gradually occupy the whole liver, promoting the disease progression.