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1.
Commun Biol ; 7(1): 490, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654111

RESUMO

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.


Assuntos
Tomografia Computadorizada por Raios X , Animais , Camundongos , Colestase/diagnóstico por imagem , Colestase/patologia , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/patologia , Progressão da Doença , Masculino , Fígado/diagnóstico por imagem , Fígado/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Imageamento Tridimensional/métodos , Infarto/diagnóstico por imagem , Infarto/patologia
2.
J Pathol ; 263(2): 178-189, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38551075

RESUMO

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.


Assuntos
Hipertensão Portal , Cirrose Hepática Biliar , Veia Porta , Hipertensão Portal/patologia , Hipertensão Portal/fisiopatologia , Animais , Cirrose Hepática Biliar/patologia , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/fisiopatologia , Masculino , Humanos , Feminino , Veia Porta/patologia , Vênulas/patologia , Ratos , Adulto , Pressão na Veia Porta , Pessoa de Meia-Idade , Modelos Animais de Doenças , Fígado/patologia , Fígado/irrigação sanguínea , Ratos Sprague-Dawley , Ductos Biliares/patologia , Adulto Jovem , Adolescente
3.
Food Chem X ; 21: 101046, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38173902

RESUMO

Triploid loquats are divided into yellow- and white-fleshed cultivars. To better understand taste variations in triploid loquat fruits, we used a UPLC-ESI-QTRAP-MS/MS-based widely targeted metabolomic analysis to examine the metabolic composition of two different color fleshed triploid loquats with a sample size of 54 and external validation method within a confidence level of P<0.05. We identified key flavor-related differentially accumulated metabolites using the variable importance in projection (VIP) value (VIP ≥ 1.0) and fold change ≥ 2 or ≤ 0.5. Furthermore, the results of the HPLC analysis showed that white-fleshed loquats had a low malic acid content. We also performed the UPLC-MS/MS system to investigate the carotenoids contents and lipidome in four triploid cultivars. In the fruits of white-fleshed varieties, the carotenoids contents were significantly downregulated, but the contents of most glycerolphospholipids were increased. Our results reveal the metabolomic changes between the yellow- and white-fleshed cultivars.

4.
Talanta ; 270: 125617, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38176250

RESUMO

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 %.

5.
J Sep Sci ; 47(2): e2300686, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286732

RESUMO

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.

6.
Plants (Basel) ; 12(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37447109

RESUMO

Calcium-dependent protein kinases (CDPK) are known to mediate plant growth and development and respond to various environmental changes. Here, we performed whole-genome identification of CDPK families in cultivated and wild mei (Prunus mume). We identified 14 and 17 CDPK genes in P. mume and P. mume var. Tortuosa genomes, respectively. All 270 CPDK proteins were classified into four clade, displaying frequent homologies between these two genomes and those of other Rosaceae species. Exon/intron structure, motif and synteny blocks were conserved between P. mume and P. mume var. Tortuosa. The interaction network revealed all PmCDPK and PmvCDPK proteins is interacted with respiratory burst oxidase homologs (RBOHs) and mitogen-activated protein kinase (MAPK). RNA-seq data analysis of cold experiments show that cis-acting elements in the PmCDPK genes, especially PmCDPK14, are associated with cold hardiness. Our results provide and broad insights into CDPK gene families in mei and their role in modulating cold stress response in plants.

7.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240174

RESUMO

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.


Assuntos
Quinases de Proteína Quinase Ativadas por Mitógeno , Prunus , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Resposta ao Choque Frio/genética , Prunus/genética , Prunus/metabolismo , Genoma de Planta , Sequência de Aminoácidos , Alinhamento de Sequência , Plantas/metabolismo , Filogenia , Regulação da Expressão Gênica de Plantas
8.
Chemosphere ; 312(Pt 1): 137328, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36410500

RESUMO

Free ammonia (FAN) inhibition is commonly encountered during high solid anaerobic digestion (HSAD) of pig manure. The performance of HSAD is highly related to its operational water regime; however, little information is available regarding the dynamics of free ammonia with varied water regimes. In this work, four treatments were set with equal amount of water supply but varied addition frequencies, i.e. add once but at different times in treatments T1 and T2, add twice in T3 while it was three times in treatment T4. Results showed that the whole methanogenic process ran smoothly with the average methane gas production rate maintaining at 191.1 LCH4/kgVSadded. Although a higher methane gas production rate of 217.4 LCH4/kgVSadded was achieved in T1, one time water addition triggered a higher ammonia inhibition potential. Cumulative FAN release was 6.03 mgFAN/kgVSadded in T1 while the balance between FAN and ammonia tended to the fraction of FAN. In T4, cumulative FAN of 5.07 mgFAN/kgVSadded was evolved, which was lower than that in T1 but similar to the situation in T2. The lowest FAN was observed in T3, indicating that a moderate frequency of dilution might be conducive to alleviate free ammonia inhibition.


Assuntos
Amônia , Esterco , Suínos , Animais , Anaerobiose , Água , Metano , Reatores Biológicos
9.
Eur Radiol ; 33(6): 4082-4093, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36576546

RESUMO

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.


Assuntos
Atresia Biliar , Humanos , Lactente , Atresia Biliar/diagnóstico por imagem , Atresia Biliar/cirurgia , Portoenterostomia Hepática/métodos , Hiperplasia , Raios X , Tomografia Computadorizada por Raios X
10.
J Plast Reconstr Aesthet Surg ; 75(11): 4243-4248, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220742

RESUMO

PURPOSE: This study aimed to investigate the efficacy and safety of canalicular laceration repair using a novel bicanalicular silicone tube. METHODS: Retrospective and consecutive patients who underwent canalicular laceration repair using novel Runshi-RS bicanalicular silicone stents from January 2020 to February 2021 were included. The stent was placed for 3 months, and patients were followed up for more than 3 months after extubation. Demographics, causes of eyelid injuries, placement time and position of stent, and surgical outcomes at follow-up were recorded. Anatomical success was evaluated by diagnostic probing and irrigation of lacrimal passage, while functional success was evaluated by the patient's subjective symptoms of epiphora. RESULTS: This study included 43 patients with canalicular laceration. The median age was 43 years (3-75 years). The average duration of stent implantation was 12.9 weeks, and the follow-up time was 8.8 months. No complications were observed in any patients during operation and follow-up. After extubation, irrigation of the lacrimal passage in 43 eyes showed no obstruction, and the anatomical success rate was 100%. Overall, 39 patients (90.7%) had no subjective symptoms of epiphora. All patients got good cosmetic results. Furthermore, subgroup classification showed deep laceration group (distance from laceration to punctum>5 mm) accounted for 51.2%, and the functional success rate of the deep laceration group was lower than that of the shallow laceration group. CONCLUSION: Runshi-RS bicanalicular silicone stent achieved good anatomical (100%) as well as functional (90.7%) success and good cosmetic results (100%) in patients with canalicular laceration repair.


Assuntos
Traumatismos Oculares , Lacerações , Doenças do Aparelho Lacrimal , Aparelho Lacrimal , Lesões dos Tecidos Moles , Humanos , Adulto , Lacerações/cirurgia , Intubação , Estudos Retrospectivos , Aparelho Lacrimal/cirurgia , Doenças do Aparelho Lacrimal/etiologia , Doenças do Aparelho Lacrimal/cirurgia , Pálpebras/cirurgia , Pálpebras/lesões , Traumatismos Oculares/cirurgia , Silicones , Stents
11.
J Chromatogr A ; 1681: 463463, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36088776

RESUMO

Covalent organic frameworks (COFs) are divided into two-dimensional (2D) and three-dimensional (3D) structures according to the connection dimension of covalent bonds. 3D COFs have smaller pore size and larger surface area, which would facilitate the separation of small organic molecules with similar structures and properties in capillary electrochromatographic (CEC) separation. However, the application of 3D COFs in CEC is still in its early stages. Thus, 3D COFs (3D-IL-COF-1 and 3D-IL-COF-2) were synthesis by a new synthesis method in this work. The related characterization results confirmed that spherical 3D-IL-COFs formed by the accumulation of small polyhedral particles were successfully synthesized. Then, 3D-IL-COFs were introduced into the inner wall of capillary by in-situ growth method to prepare the 3D COFs coated capillaries for the first time. The electrochromatographic separation performance of the 3D-IL-COFs coated capillaries was investigated using the 3D-IL-COF-1 coated capillary as the model. The results indicate that the 3D-IL-COF-1 coated capillary with uniform coating exhibits a broad-spectrum separation capacity not only for acidic, basic and neutral analytes but also for neutral isomers, which shows that 3D-IL-COFs becomes an attractive potential stationary phase for electrochromatographic separation.

12.
Transl Vis Sci Technol ; 11(8): 1, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913417

RESUMO

Purpose: The purpose of this study was to evaluate the pathological involvement of erythropoietin (EPO) in experimental choroidal neovascularization (CNV) and its association with neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in the Chinese population. Methods: Treatment effect of recombinant EPO protein were assessed by human umbilical vein endothelial cell (HUVEC) proliferation, migration, and tube formation, and ex vivo choroid-sprouting ability. The effect of intravitreal injection of Epo siRNA against neovascularization was evaluated in the laser-induced CNV mouse model. In addition, the association of EPO variants with neovascular AMD and PCV was determined. Results: Exogenous supplementation of EPO significantly enhanced the migration and tube formation of HUVECs and promoted ex vivo choroid sprouting in mouse retinal pigment epithelium (RPE)-choroid-sclera complex culture. In the experimental CNV mouse model, Epo expression was found to be significantly upregulated by 3.5-folds in RPE-choroid-sclera complex at day 10 after laser induction as compared to the baseline. Immunofluorescence analysis showed that Epo was mainly expressed around the vascular endothelial cells in the RPE-choroid-sclera complex. Intravitreal injection of siRNA targeting Epo reduced 40% Epo expression and 40% CNV lesion areas as compared to the scramble control. However, EPO variants were not associated with neovascular AMD nor PCV in the Chinese population. Conclusions: This study revealed the promotion of human endothelial cell tube formation in vitro and choroid sprouting ex vivo by EPO, and the reduction of laser-induced CNV in vivo by Epo RNA interference. Translational Relevance: Targeting EPO could be a potential additional treatment for CNV-related diseases.


Assuntos
Doenças da Coroide , Neovascularização de Coroide , Eritropoetina , Degeneração Macular Exsudativa , Inibidores da Angiogênese , Animais , Doenças da Coroide/genética , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/genética , Eritropoetina/genética , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Lasers , Camundongos , Interferência de RNA , RNA Interferente Pequeno/genética , Acuidade Visual , Degeneração Macular Exsudativa/genética
13.
J Chromatogr A ; 1677: 463289, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35820229

RESUMO

Covalent organic frameworks (COFs) have great potential applications in chromatographic separation. So it is crucial to understand the relationship between the separation ability of COFs and their structures. Here we report a strategy to evaluate the separation ability of three 2D COFs and explore the relationship between separation ability and their molecular structures. The three 2D COFs (COF-LZU1, COF-42 and COF-LZU8) have one same building unit 1,3,5-triformylbenzene, while varied from the conjugated linking units and functional side-chains. They were used to construct coated capillary column for capillary electrochromatographic separation of same groups of phthalates. They exhibited different separation efficiencies. COF-42 and COF-LZU8 coated capillary columns provided good signal resolutions and high column efficiencies with high theoretical plate numbers. It is demonstrated that COFs with hydrazone unit and longer side-chains provided higher selectivity and resolutions for the phthalates separation. Molecular simulations and DFT calculations were further proceeded to explore the deep reason why the three COFs coated CEC displayed different separation ability based on the host-guest interactions on molecular level. This work highlights a new opportunity to select or design functional COFs and improve their efficiency in chromatographic separation based on host-guest chemistry.

14.
J Chromatogr A ; 1670: 462943, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35306370

RESUMO

Chiral covalent organic frameworks (CCOFs) have recently exhibited particularly promising potential as effective chiral stationary phases (CSPs) for open tubular capillary electrochromatography (OT-CEC) enantioseparation. However, it remains difficult to synthesis of CCOFs and preparation of CCOFs coated capillary under mild reaction conditions. In this work, we designed and fabricated a CCOF (CB-DA-COF) with high chemical stability and high specific surface area at room temperature. Then, through one-step in situ growth method, the chiral CB-DA-COF coated capillary was fabricated at room temperature for the first time. This method requires neither pre-modification to the capillary by organic molecular building units nor harsh reaction conditions, and the preparation time of the CCOF coating was significantly shortened (within 2 h). This chiral CB-DA-COF coated capillary showed excellent enantioseparation ability and stability. Under optimal conditions, rapid enantioseparation (within 5 min) could be achieved for six enantiomers including terbutaline, propranolol, phenylephrine, verapamil, norepinephrine and isoprenaline. And, no significant change was observed in enantioseparation efficiency after over 200 runs. The relative standard deviations (RSDs) of the analyte's migration time for intra-day, inter-day and column-to-column were within the range of 0.8-3.5% (n = 5), 1.5-4.7% (n = 3) and 4.3-8.3% (n = 3), respectively. In addition, the enantioseparation mechanism was studied, which indicated that binding energy between of enantiomers and chiral site were the main factors for enantioseparation.


Assuntos
Eletrocromatografia Capilar , Estruturas Metalorgânicas , Eletrocromatografia Capilar/métodos , Estruturas Metalorgânicas/química , Estereoisomerismo , Terbutalina
15.
Quant Imaging Med Surg ; 12(2): 979-991, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111599

RESUMO

BACKGROUND: Vascular changes in liver fibrosis can result in increased intrahepatic vascular resistance and impaired blood circulation. This can hinder the recovery from fibrosis and may eventually lead to portal hypertension, a major cirrhosis complication. This report proposed a volume-averaged Murray's deviation method to characterize intrahepatic circulation in the liver during fibrosis and its subsequent regression via X-ray phase-contrast computed tomography (PCCT). METHODS: Liver fibrosis was induced in 24 Sprague-Dawley rats by exposure to carbon tetrachloride (CCl4) for up to 10 weeks, after which, spontaneous regression commenced and continued until week 30. High-resolution three-dimensional (3D) imaging of the livers was performed with PCCT. The values of Murray's deviation based on the volume-averaged and the conventional diameter-based methods were compared. After that, the intrahepatic circulation at different stages of fibrosis was evaluated using the volume-averaged method. The increase in collagen during liver fibrosis was assessed by pathological analyses. RESULTS: A comparison of the 2 methods showed that with an increase in the number of diameter measurements, the value of Murrary's deviation obtained using the diameter-based method gradually approaches those of the volume-averaged method, with minimal variations. The value of Murray's deviation increased with the development of fibrosis. After reversal, the value rapidly decreased and approached that of the normal state in both the main branches (1.05±0.17, 1.17±0.21, 1.34±0.18, and 1.17±0.19 in the normal, moderate, severe, and regressive groups, respectively; P<0.05 between the severe group and other groups) and the small branches (1.05±0.09, 1.42±0.48, 1.79±0.57, and 1.18±0.28 in the normal, moderate, severe, and regressive group, respectively; P<0.05 between adjacent groups). An analysis of Murray's deviation and the pathological results showed that the vascular circulation in this disease model was consistent with the progression and recovery from fibrosis. CONCLUSIONS: This study showed the validity of the volume-averaged method for calculating Murray's deviation and demonstrated that it could accurately evaluate the blood circulation state of the liver during fibrosis and its subsequent regression. Thus, the volume-averaged method of calculating Murray's deviation may be an objective and valuable staging criterion to evaluate intrahepatic circulation during liver fibrosis.

16.
Eur J Radiol ; 148: 110178, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35091166

RESUMO

PURPOSE: Differentiating the intrahepatic vascular type is essential for the early diagnosis of liver fibrosis. X-ray phase-contrast computed tomography (PCCT) is a label-free, high-resolution imaging modality for imaging vascular networks in a whole liver lobe. This study explores the use of three-dimensional (3D) branching geometry to differentiate between the hepatic vein (HV) and portal vein (PV) in early-stage liver fibrosis with PCCT. METHOD: Bile duct ligation surgery was conducted in mice to induce early-stage liver fibrosis. The individual liver lobes of mice were imaged using PCCT, and morphological characteristics, including vascular diameter, cross-sectional area, eccentricity, branch angle, bifurcation index, area ratio and junction exponent, were investigated in 3D modality. These characteristics were used to differentiate the HV from the PV, and their performance was evaluated through receiver operating characteristic (ROC) curve analysis. RESULTS: PCCT revealed a 3D vascular structure of the liver lobes. For intact lobes, the differentiation method between the HV and PV using the junction exponent had an AUC of 0.99 (95% CI: 0.98-1.00). Moreover, the AUCs of the junction exponent for 15, 10, and 5 branches in dissected lobes for differentiation were 0.98 (95% CI: 0.94-1.00), 0.86 (95% CI: 0.73-0.99) and 0.82 (95% CI: 0.67-0.97), respectively. CONCLUSION: The method of 3D branching geometry using the junction exponent could differentiate the HV from PV in early-stage liver fibrosis via the PCCT, which provides the foundation for further analysis of liver fibrosis.


Assuntos
Imageamento Tridimensional , Cirrose Hepática , Animais , Imageamento Tridimensional/métodos , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Camundongos , Tomografia Computadorizada por Raios X/métodos , Raios X
17.
Graefes Arch Clin Exp Ophthalmol ; 260(1): 73-81, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34309768

RESUMO

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.


Assuntos
Membrana Epirretiniana , Degeneração Macular , Miopia Degenerativa , Membrana Basal/cirurgia , Membrana Epirretiniana/cirurgia , Fóvea Central , Humanos , Miopia Degenerativa/complicações , Miopia Degenerativa/diagnóstico , Miopia Degenerativa/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Tração , Acuidade Visual , Vitrectomia
18.
Chem Commun (Camb) ; 58(3): 403-406, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34897307

RESUMO

Herein, a novel chiral covalent organic framework, DA-TD COF, with good chemical/thermal stability was synthesized and used as a chiral stationary phase for open-tubular capillary electrochromatography enantioseparation. The DA-TD COF coated capillary exhibited excellent enantioseparation efficiency and its separation efficiency did not show an obvious decrease over 200 runs. Furthermore, the enantioseparation mechanism was studied.

19.
Med Phys ; 49(1): 393-410, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34854084

RESUMO

PURPOSE: High-resolution synchrotron radiation X-ray phase contrast microtomography (PC-µCT) images often suffer from severe ring artifacts, which are mainly caused by undesirable responses of detector elements. In the medical imaging field, the existence of ring artifacts can lead to degraded visual quality and can directly affect diagnosis accuracy. Thus, removing or at least effectively reducing ring artifacts is indispensable. METHOD: The existing ring artifacts removal algorithms mainly focus on two-dimensional (matrix-based) priors, and these algorithms fail to consider correlations hidden in sequential computed tomography (CT) images. This paper proposed a novel three-dimensional (tensor-based) ring artifacts removal algorithm for synchrotron radiation X-ray PC-µCT images. In the sinogram domain, ring artifacts manifest as vertical stripe artifacts. From an image decomposition perspective, a degraded sinogram can be decomposed into a stripe artifacts component and an underlying clean sinogram component. The proposed algorithm is designed to detect and remove stripe artifacts from a degraded sinogram by fully identifying the characteristics of the two components. Specifically, for the stripe artifacts component, tensor Tucker decomposition is used to describe its low-rank character. For the underlying clean sinogram component, spatial-sequential total variation regularization is adopted to enhance the piecewise smoothness. Moreover, the Frobenius norm term is further used to model Gaussian noise. An efficient augmented Lagrange multiplier method is designed to solve the proposed optimization model. RESULTS: The proposed method is evaluated utilizing both simulations and real data containing different ring artifacts patterns. In the simulations, the human chest CT images are used for evaluating the proposed method. We compare the peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and mean absolute error (MAE) results of our algorithm with the Naghia's method, the RRRTV method, the wavelet-FFT method, and the SDRSD-GIF method. The proposed method was also evaluated on real data from rat liver samples and rat tooth samples. Our proposed method outperforms the competing methods in terms of both qualitative and quantitative evaluation results. Additionally, the 3D visualization results were presented to make the ring artifacts removal effect more intuitive. CONCLUSION: The experimental results on simulations and real data clearly demonstrated that the proposed algorithm can significantly improve the quality of PC-µCT images compared with the existing popular algorithms, and it has great potential to promote the application of high-resolution imaging for visualizing biological tissues.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador , Algoritmos , Animais , Imagens de Fantasmas , Ratos , Microtomografia por Raio-X
20.
J Chromatogr A ; 1661: 462681, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34856505

RESUMO

Recently, covalent organic frameworks (COFs), owning to their excellent and unique properties, are attracting the attention of numerous researchers in some areas, especially the domain of chromatographic separation. However, the application of hydrazine linkages COFs in open-tubular capillary electrochromatography (OT-CEC) lies in the early stage at present. Herein, a well-crystallized hydrazine-linked COF (Tf-DHzOH) was synthesized successfully from 2,5-dihydroxyterephtalohydrazide and 1,3,5-triformyl-benzene. Tf-DHzOH was firstly regarded as a stationary phase material to prepare the Tf-DHzOH coated capillaries with different coating thickness by covalent bonding in this work. The characterization results showed that Tf-DHzOH was successfully synthesized. The separation performance and stability of the Tf-DHzOH coated capillary were evaluated by considering amino acids, sulfonamides, tetracyclines and benzene compounds as analytes. The relative standard deviations (RSDs) of separation time in the intra-day (n = 9), inter-day (n = 6), column-to-column (n = 3) and batch-to-batch (n = 3) were 0.76-4.97%, 1.59-5.94%1.78-8.72% and 1.66%-8.23%, respectively, the RSDs of peak areas were 1.90-5.16%, 1.73-5.24%, 1.26-7.33% and 3.77%-11.24%, respectively. It was confirmed that there was no visible change of separation efficiency after the Tf-DHzOH-coated capillary was used more than 200 runs. The results make clear that 2D hydrazine-linked COF (Tf-DHzOH) has superior potential as the stationary phase in OT-CEC for chromatographic separation.


Assuntos
Eletrocromatografia Capilar , Estruturas Metalorgânicas , Aminoácidos , Hidrazinas
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