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1.
Sensors (Basel) ; 24(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38339441

RESUMO

CdZnTe (CZT) is a new type of compound semiconductor that has emerged in recent years. Compared to other semiconductor materials, it possesses an ideal bandgap, high density, and high electron mobility, rendering it an excellent room-temperature composite semiconductor material for X-ray and γ-ray detectors. Due to the exceptional performance of CZT material, detectors manufactured using it exhibit high energy resolution, spatial resolution, and detection efficiency. They also have the advantage of operating at room temperature. CZT array detectors, furthermore, demonstrate outstanding spatial detection and three-dimensional imaging capabilities. Researchers worldwide have conducted extensive studies on this subject. This paper, building upon this foundation, provides a comprehensive analysis of CZT crystals and CZT array detectors and summarizes existing research to offer valuable insights for envisioning new detector methodologies.

2.
Appl Radiat Isot ; 199: 110867, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37300927

RESUMO

An effective standoff alpha radiation measurement of surface contamination method is of great importance in radioactive waste disposal and decommissioning of nuclear facilities, nuclear accident emergency response and nuclear security. Here, we build an optical system for the implementation of standoff alpha radiation measurement based on radioluminescence. We present the results of the detection efficiency calibrating of standoff alpha radioactive sources using simulation and experiment. At the same time, a numerical integration-based surface contamination measurement method is designed, computed, and validated through experiments and simulations. Finally, the minimum detectable surface activity of the method is given for different measurement conditions.

3.
Sci Rep ; 12(1): 9418, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676527

RESUMO

As essential high-end equipment for nuclear emergency monitoring, the portable HPGe γ spectrometer currently lacks supporting in-situ measurement methods, limiting its role and value in emergency missions. For this practical problem, this paper studies the measurement of ground surface radioactivity by portable HPGe γ spectrometer in nuclear emergency monitoring in view of the particularity of nuclear emergency source items. Firstly, the detection efficiency of point sources at different horizontal distances when the spectrometer is installed at the height of 1 m from the center of the detector to the ground is calculated. Secondly, the concept of effective contribution distance is defined and analyzed. Thirdly, the point source detection efficiency is obtained using the numerical integration method of calculation. Integrate to calculate the detection efficiency of the surface source, and then calculate the radioactive surface activity of the surface. Finally, the effectiveness of the method is verified through experiments.

4.
Ann Transl Med ; 10(10): 536, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35722385

RESUMO

Background: Hepatitis B virus (HBV) can encode microRNA-HBV-miR-3, which can be detected in both HBV-infected cell lines and peripheral blood exosomes of chronic hepatitis B (CHB) patients. This study was conducted to further evaluate its relationship with the current viral markers and their dynamics during antiviral therapy. Methods: We used Stem-loop real time quantitative PCR (RT-qPCR) to quantify HBV-miR-3 in the serum exosomes of CHB patients by extracting exosomes using the Supbio exosome separation kit and designing primers and Taqman probes specific for HBV-miR-3. We conducted a cross-sectional study and two cohort studies. In the cross-sectional study, 48 treatment-naive (TN) CHB patients were enrolled. In the nucleoside analogues (NAs) cohort study, 20 hepatitis B e antigen (HBeAg) negative CHB patients with negative HBV DNA on NA therapy were followed up for 96 weeks. In the NAs + pegylated interferon (Peg-IFN) cohort study, 40 patients with hepatitis B surface antigen (HBsAg) <1,500 IU/mL, negative HBV DNA, and HBeAg after NAs treatment were enrolled and were switched to Peg-IFN therapy for 48 weeks. HBV-miR-3 titers and other viral markers were detected at different time points. Results: HBV-miR-3 only existed in CHB patients with a concentration of 6.41±3.55 log10 copies/mL. HBV-miR-3 was positively correlated with HBV DNA, pregenomic RNA (pgRNA), and HBsAg. In the NAs cohort, HBsAg, pgRNA, and HBV-miR-3 levels showed little fluctuation during the 96 weeks of NA treatment (P>0.05). In the NAs + PEG-IFN cohort, HBsAg, pgRNA, and HBV-miR-3 levels declined significantly during the 48 weeks of sequential therapy (P<0.05). Conclusions: HBV-miR-3 was positively correlated with HBV DNA, pgRNA, and particularly HBsAg in TN CHB patients. Peg-IFN following NA therapy had a positive impact on HBsAg, pgRNA, and HBV-miR-3 decrease.

5.
Ann Transl Med ; 9(18): 1431, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733983

RESUMO

BACKGROUND: While serum hepatitis B surface antigens (HBsAg) play an important role in the diagnosis and assessment of treatment results of hepatitis B virus (HBV) infections, it remains unclear whether HBsAg levels normalized to hepatic parenchymal cell volume (HPCV) is a superior indicator of disease state. This study compared the absolute and HPCV-normalized serum HBsAg levels in hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with chronic hepatitis B (CHB). METHODS: Patients admitted to our institution with CHB were retrospectively included and categorized into the HBeAg-positive and HBeAg-negative groups. HPCV was calculated based on pathological examination of liver biopsy specimens and theory of sphere geometry. The difference between HBsAg levels and HBsAg normalized to HPCV, and also correlation between HBsAg levels and liver inflammation and fibrosis was analyzed. RESULTS: Absolute HBsAg levels (P=0.004), but not HPCV-normalized HBsAg levels (P=0.071) were significantly higher in HBeAg-positive patients compared to HBeAg-negative patients. In HBeAg-positive CHB patients, absolute HBsAg levels were positively correlated with liver inflammation grade (R=0.285, P=0.001) and hepatic fibrosis stage (R=0.351, P<0.001), as were HPCV-normalized HBsAg levels (R=0.640 and 0.742, both, P<0.001). However, in HBeAg-negative CHB patients, only HPCV-normalized HBsAg level were correlated with liver inflammation grade and hepatic fibrosis stage (R=0.640 and 0.785, both, P<0.001). CONCLUSIONS: HPCV-normalized serum HBsAg levels, rather than absolute HBsAg levels, were positively correlated with liver inflammation grade and hepatic fibrosis stage in both HBeAg-positive and HBeAg-negative CHB patients. Thus, HPCV-normalized HBsAg levels may more accurately reflect the pathological progress of CHB patients compared to absolute HBsAg levels.

6.
Ann Transl Med ; 9(5): 414, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33842635

RESUMO

BACKGROUND: The seroconversion of the hepatitis B antigen is the ideal outcome for long-acting interferon-pegylated interferon-α (Peg-IFN-α) treatment among patients with chronic hepatitis B (CHB). B-cell response plays an important role in the process of hepatitis B antigen clearance, but the specific mechanism by which B-cell improve hepatitis B virus (HBV) is still unclear. METHODS: A total of 103 CHB patients participated in this study. The patients received 24 weeks of Peg-IFN-α treatment. Flow cytometry was used to detect B-cell surface markers' cluster of differentiation cluster of differentiation CD19, CD24, and CD27 in the peripheral blood mononuclear cells (PBMCs) of CHB patients before and after 24 weeks of Peg-IFN-α treatment. RESULTS: After 24 weeks of Peg-IFN-α treatment, the content of memory B cells (CD19+CD27+) and effector B cells (CD19+CD38+) increased significantly. Further analysis showed that the clearance of the hepatitis B antigen was correlated with the change value, ΔT, of plasma cells before and after treatment. The B-cell subsets (CD19+CD24+; CD19+CD40+; CD19+CD40+; CD19+CD80+), was also tested and the results showed that CD19+CD24+ and CD19+CD80+ content also increased significantly after treatment. CONCLUSIONS: After Peg-IFN-α treatment, the B-cell subsets of CHB patients are remodeled. Thus, Peg-IFN-α treatment appears to play an important role in the remodeling of B cell subsets and the clearance of HBV antigens. The results of this study provide a theoretical basis and guidance for the clinical treatment of CHB.

7.
Clin Res Hepatol Gastroenterol ; 45(6): 101631, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33662775

RESUMO

OBJECTIVE: Radioiodine (Iodine-131, 131I) ablation is a standard treatment for differentiated thyroid cancer (DTC) after thyroidectomy. Hepatotoxicity is a rare side effect of 131I, and little information is available on the hepatotoxicity of 131I ablation for post-surgical DTC patients with hepatitis B virus (HBV) infection. METHODS: We performed a retrospective study of 94 post-surgical DTC patients between November 2012 and August 2015 in our hospital. All the patients had been screened for HBV infection and divided into HBV group and non-HBV group. Clinical data were compared between the two groups. RESULTS: 14 patients with HBV infection and 80 patients without HBV infection were analyzed. The baseline characteristics of the two groups had no statistical differences. Incidence of hepatotoxicity was higher in HBV group than in non-HBV group and HBV infection was confirmed as a risk factor of hepatotoxicity by univariate and multivariate regression analysis. CONCLUSION: Post-surgical DTC patients with HBV infection were prone to hepatotoxicity by 131I ablation treatment. Physicians should pay more attention to the liver function of patients at risk.


Assuntos
Adenocarcinoma , Doença Hepática Induzida por Substâncias e Drogas , Hepatite B , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Hepatite B/epidemiologia , Humanos , Radioisótopos do Iodo/toxicidade , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia
8.
Sensors (Basel) ; 22(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35009745

RESUMO

The detection of α particles is of great significance in military and civil nuclear facility management. At present, the contact method is mainly used to detect α particles, but its shortcomings limit the broad application of this method. In recent years, preliminary research on noncontact α-particle detection methods has been carried out. In this paper, the theory of noncontact α-particles detection methods is introduced and studied. We also review the direct detection and imaging methods of α particles based on the different wavelengths of fluorescence photons, and analyze the application and development of this method, providing an important reference for researchers to carry out related work.


Assuntos
Partículas alfa
9.
Ann Palliat Med ; 10(2): 1388-1395, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33183037

RESUMO

BACKGROUND: This study aimed to investigate the dynamic changes of serum HBV DNA and hepatitis B surface antigen (HBsAg) titers apportioned by the same hepatic parenchyma cell volume (HPCV) at different liver histological inflammation grades in the natural history of chronic hepatitis B (CHB). METHODS: The serum HBV DNA and HBsAg titers were detected by real-time polymerase chain reaction and electrochemiluminescence, separately, in CHB patients without any treatment. The serum HBV DNA levels and HBsAg titers apportioned by the same HPCV were figured out based on sphere geometry theory. In addition, the differences of HBV DNA levels and HBsAg titers apportioned by the same HPCV in different liver inflammation grades were further assessed based on statistical analysis. RESULTS: There was no difference of serum HBV DNA levels or HBsAg titers before apportioned by the same HPCV in liver inflammation grades 1-4, but significant differences were observed after apportion in CHB patients (HBV DNA: P=0.101; HBsAg: P=0.211 & HBV DNA apportioned by HPCV: P<0.001; HBsAg apportioned by HPCV: P<0.001). No correlation was observed between HBV DNA levels and liver inflammation grades (r=0.083, P=0.186), or between HBsAg titers and liver inflammation grades (r=0.083, P=0.078). A significant correlation was observed between HBV DNA levels apportioned by HPCV and liver inflammation grades (r=0.249, P<0.001), and obvious correlation of HBsAg titers apportioned by HPCV and liver inflammation grades was also found in CHB patients (r=0.554, P<0.001). CONCLUSIONS: These results suggest that the levels of serum HBV DNA and HBsAg apportioned by the same HPCV are correlated with the severity of liver histological inflammation grade in the natural history of CHB.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Tamanho Celular , DNA Viral , Vírus da Hepatite B/genética , Humanos , Inflamação
10.
World J Gastroenterol ; 21(9): 2739-45, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25759544

RESUMO

AIM: To investigate the dynamic changes of serum hepatitis B surface antigen (HBsAg) levels apportioned by the same hepatic parenchyma cell volume (HPCV), namely, hepatic cell quantities. METHODS: Serum HBsAg levels were detected by electrochemiluminescence and serum HBsAg levels apportioned by the same HPCV were figured out according to the theory of sphere geometry. HBsAg levels were compared among different liver inflammation grades, as well as different hepatic fibrosis stages. RESULTS: In hepatitis B e antigen-negative chronic hepatitis B, serum HBsAg levels in liver histological inflammation grades 1-4 were 3.66 ± 0.40, 3.74 ± 0.35, 3.74 ± 0.26 and 3.71 ± 0.34 log10 COI (cut off index), respectively, and there were no differences before apportion (P = 0.640). Serum HBsAg levels apportioned by the same HPCV were 5.57 ± 0.62, 5.98 ± 0.65, 6.59 ± 0.50 and 6.81 ± 0.84 log10 COI, respectively, and there were significant differences after apportion (P < 0.001). Serum HBsAg levels in hepatic fibrosis stages I-IV were 3.66 ± 0.43, 3.75 ± 0.33, 3.71 ± 0.28 and 3.75 ± 0.26 log10 COI, respectively, and there were no differences before apportion (P = 0.513). Serum HBsAg levels apportioned by the same HPCV were 5.53 ± 0.66, 5.98 ± 0.53, 6.29 ± 0.46 and 7.06 ± 0.48 log10 COI, respectively, and there were significant differences after apportion (P < 0.001). CONCLUSION: Serum HBsAg levels apportioned by the same HPCV (hepatic cell quantities), rather than serum HBsAg levels, increase with liver inflammation grades and hepatic fibrosis stages.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Cirrose Hepática/diagnóstico , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/complicações , Humanos , Fígado/patologia , Fígado/virologia , Cirrose Hepática/sangue , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Testes Sorológicos , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
11.
Zhonghua Gan Zang Bing Za Zhi ; 22(12): 895-9, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25654281

RESUMO

OBJECTIVE: To investigate the dynamic changes in serum levels of hepatitis B surface antigen (HBsAg) and their relation to hepatic parenchyma cell volume (hepatic cell quantity) at different grades of liver inflammation and stages of hepatic fibrosis in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. METHODS: Serum HBsAg levels were detected by electrochemilumineseence. Serum HBsAg levels were apportioned according to the hepatic parenchyma cell volume and compared among liver histological inflammation grade (1, 2, 3 and 4) and hepatic fibrosis stage ( I, II, III and IV), respectively. RESULTS: The levels of serum HBsAg among the four liver histological inflammation grades were:1:6,036.4+/-2,729.4 COI/ml; 2:6,704.6+/-2,457.5 COI/ml; 3:6,332.2+/-2,409.0 COI/ml; 4:6,226.2+/-2,716.0 COI/ml. There were no differences among the groups before apportion (Fbefore apportion=0.564, P=0.640).Serum HBsAg levels apportioned by the hepatic parenchyma cell volume among liver histological inflammation grades were:1:9,174.8+/-4,142.0 COI/ml; 2:10,743.1+/-3,950.3 COI/ml; 3:11,078.0+/-4 230.0COI/ml; 4:11,540.5+/-5,058.8 COI/ml. There were significant differences among the groups after apportion (Fafter apportion =27.354, P<0.001). Serum HBsAg levels among hepatic fibrosis stages were: I: 6,222.1+/-2,665.4 COI/mL; II: 6,706.8+/-2,623.8 COI/ml; III:6 004.5+/-2,625.5 COI/ml; IV:6,455.6+/-2,344.4 COI/ml. There were no differences among groups before apportion (Fbefore apportion=0.768, P=0.513).Serum HBsAg levels apportioned by the hepatic parenchyma cell volume (hepatic cell quantity) among hepatic fibrosis stages were: I :9 417.5+/-4,034.2 COI/ml; II :10,093.3+/-4,183.4 COI/ml; III:10,177.1+/-4,445.0 COI/ml; IV:12,166.6+/-4,418.5 COI/ml. There were significant differences among the groups after apportion (Fafter apportion=57.077, P<0.001). CONCLUSION: Serum HBsAg levels apportioned by the same hepatic parenchyma cell volume (hepatic cell quantity), rather than serum HBsAg levels, increased with hepatic pathological progress.


Assuntos
Hepatite B , Cirrose Hepática , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B , Hepatócitos , Humanos , Inflamação
12.
Zhonghua Gan Zang Bing Za Zhi ; 20(10): 742-5, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23207333

RESUMO

The aim of this study was to determine the dynamic expression profile of hepatitis B surface antigen (HBsAg) according to hepatic parenchyma cells' volume at different stages of liver fibrosis during the immune clearance phase. Eighty-nine patients with HBeAg-positive chronic hepatitis B (CHB) in the immune clearance stage were recruited for study. Each patient's serum HBsAg levels were detected by electrochemiluminescence. The serum HBsAg levels were apportioned according to hepatic parenchyma cells' volume at liver fibrosis stages 1, 2, 3, and 4 and compared by ANOVA. The unapportioned serum HBsAg levels (IU/mL) at liver fibrosis stages 1 (227.2+/-237.7), 2 (211.0+/-131.4), 3(300.1+/-144.6), and 4 (278.7+/-148.8) were not significantly different (all comparisons, P range: 0.061 to 0.759). However, when the serum HBsAg levels were apportioned by the same hepatic parenchyma cells' volume at liver fibrosis stages 1 (343.9+/-359.8), 2 (336.4+/-209.5), 3 (508.7+/-245.1), and 4 (525.2+/-274.8), the levels were significantly different (all comparisons, F = 3.045 and P = 0.033; stage 1 vs. 3, P = 0.041; stage 1 vs. 4, P = 0.046; stage 2 vs. 3, P = 0.028; stage 2 vs. 4, P = 0.034). During the immune clearance phase of chronic hepatitis B, increased HBsAg expression is associated with increased hepatic parenchyma cells' volume and progressive liver fibrosis stage.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Adolescente , Adulto , Tamanho Celular , Criança , Feminino , Hepatite B Crônica/patologia , Humanos , Fígado/citologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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