The influence of different CT scanning protocols on AI detection efficiency and radiation dose of solid nodules in chest phantom / 中华放射医学与防护杂志

Objective:To investigate the radiation dose and detection efficiency of artificial intelligence (AI) system for solid nodules in chest phantom with different scanning protocols.Methods:A total of 60 simulated nodules with different CT values and diameters were uniformly placed in each lung lobe and lung segment of the anthropomorphic chest phantom. GE Revolution evo CT was used to scan the chest phantom. 64 groups of images with different scanning parameters were collected at the tube voltage of 80, 100, 120, 140 kV, different noise indexes (NI 10-40 with interval 2), and other fixed parameters. The detection result of simulated nodules were recorded on AI software, and the detection rate and false detection rate were calculated, respectively, for different shapes of nodules. The mean volume CT dose index (CTDI vol) and dose length product (DLP) of each scan were recorded. Results:There were no statistically significant differences in the detection rate and false detection rate of spherical nodules and irregular nodules at different tube voltages( P > 0.05), but there were and statistically significant with different noise indices ( F=10.57, 17.77, 9.33, P < 0.001). Different tube voltages had no statistical significance for CTDI vol and DLP ( P > 0.05), while different noise indices had statistical significance for CTDI vol and DLP ( F=59.87, 60.92, P < 0.001). The detection rates of nodules were moderately or weakly correlated with noise indices, CTDI vol and DLP ( r=0.43, 0.56, -0.58, -0.78, P<0.05), but no correlation with tube voltage ( P>0.05). Conclusions:Scanning protocol has an impact on AI detection efficiency of pulmonary nodules. Reasonable scanning parameters should be selected according to different image quality requirements in clinical practice.

Effects of organ dose modulation technique on image quality and radiation dose in sinus CT scanning / 中华放射医学与防护杂志

Objective:To investigate the effects of organ dose modulation (ODM) on image quality and radiation dose to lens during sinus CT scanning.Methods:The GE Revolution EVO CT was used to scan the anthropomorphic head with ODM turned off as the control group and ODM turned on as the observation group. With different parameter combinations of tube voltage (140, 120, 100 kV), noise index (N17, N18), pitch (0.531, 0.969 at 20 cm collimation width, 0.516, 0.984 at 40 mm collination width), 24 series of images were acquired respectively. The tube current (mA) valuesat the anterior (A), left (L), posterior (P) and right (R) positions, volume CT dose index (CTDI vol) and dose length product (DLP) were recorded. Average CT values (AV), standard deviation (SD), signal-to-noise ratio (SNR), contrast to noise ratio (CNR) and image quality factor (FOM) of ROI were calculated. Double blind method was used to evaluate the edge sharpness, soft tissue level, noise and artifact on a subjective scale of 3 points. Results:For the combinations of different scanning parameters, the radiation dose of the observation group was lower than that of the control group. The tube current attheposition A for the observation group was lower than that of the control group, and the difference was statistically significant ( t=2.28, P<0.05). The differences oftube currentsatposotions of L, P and R, CTDI vol and DLP values in twogroupswere not statistically significant ( P>0.05). There were no significant differences in SD, SNR, CNR and FOM between the two groups of images ( P>0.05). There were no significant differences in the subjective scores of edge sharpness, soft tissue gradation, noise and artifacts between the two groups ( P>0.05). Conclusions:ODM technique can effectively reduce the radiation dose of eye lens without decompromising the image quality, which could meet the requirements of diagnosis, and accord with the principle of radiological protection optimization.

Study on image quality optimization of abdominal digital radiography with different additional filters / 中华放射医学与防护杂志

Objective:To investigate the effect of different additional filters on the image quality and radiation dose in abdominaldigital radiography (DR).Methods:Retrospective analysis was performed on 10 cases of abdominal DR from December 2020 to January 2021 in Fuxing Hospital, and the average mAs was calculated. Using automatic exposure control (AEC) technology, a polymethyl methacrylate (PMMA) slab of the corresponding thickness (18 cm) at the same output of above mAs was confirmed and used as the attenuator to simulate the abdomen. The phantom of CDRAD 2.0 and 17 slices of 10 mm thick PMMA plates (total thickness 18 cm) were placed on the bed. The additional filters were selected as no additional filter, 2 mmAl, 0.1 mmCu+ 1 mmAl, 0.1 mmCu+ 2 mmAl respectively. The AEC levels were selected at -2, -1, 0, 1, and 2 respectively. The images were collected and analyzed by using CDRAD 2.0 software to obtain the image quality factor (IQF inv). The incident air kinetic energy on the surface of the PPMA was measured for each exposure, and PCXMC software was used to estimate the organ dose and effective dose, and a comparative analysis was made. Results:The skin incident doses at no additional filter, 2 mmAl, 0.1 mmCu+ 1 mmAl, 0.1 mmCu+ 2 mm Al were (0.546 1±0.200 8), (0.376 2±0.133 8 ), (0.285 3±0.100 1) and (0.289 9±0.099 2) mGy, respectively. The estimated effective doses were (79.63±29.24)×10 -3, (71.05±25.56)×10 -3, (63.58±22.18)×10 -3 and (67.64±23.11)×10 -3 mSv, respectively. The gonadal doses were (0.058 1±0.020 8), (0.050 0±0.018 0), (0.044 8±0.015 6) and (0.047 7±0.016 3) mGy.The IQF inv values were 4.70±0.61, 4.80±0.84, 4.60±0.55, 4.60±0.60, respectively. There were linear correlations between the effective dose and the skin incident dose under different additional filtration, and the effective doses increased with the increase of the incident doses. The dose was lowest at the addition filtration of 0.1 mmCu+ 1 mmAl. There was no significant difference in the IQF inv between groups( P>0.05). Conclusions:The optimal additional filtration for abdominal DR was 0.1 mmCu+ 1 mmAl with the image quality meeting the requirements of clinical diagnosis, the radiation dose reduced reasonably, and the objective of the optimization of radiographic parameters achieved.

Intermedin1-53 inhibits collagen synthesis induced by angiotensinⅡin cadiac fibroblasts of rats / 基础医学与临床

Objective To investigate collagen metabolism modulation of Intermedin 1-53 ( IMD1-53 ) on angiotensin Ⅱ( AngⅡ)-induced rat cardiac fibroblasts .Methods SD neonatal rat cardiac fibroblasts were cultured and divided them into control group, AngⅡ +different concentrations IMD1-53 groups.ⅠandⅢcollagen expression in cardiac fibroblasts were measured by Westem blot , IMD1-53 receptor-like receptor ( calcitonin receptor-like receptor , CRLR) and transforming growth factor-β( TGF-β) mRNA expression were exammed by real-time PCR.Results IMD1-53 significantly inhibited AngⅡ-induced collagen synthesis in cardiac fibroblasts , and this effect was more ob-vious with the increase of IMD 1-53 ( P<0.01 ,P<0.05 ) .Similar phenomenon was recorded in TGF-βexpression in cardiac fibroblasts ( P<0.05 ) .Conclusions IMD1-53 inhibited collagen synthetic in cardiac fibrosis induced by AngⅡ, down-regulated TGF-βexpression.These may relate to IMD1-53 anti myocardial fibrosis.

Effects of Chronic Mild Stress in Female Bax Inhibitor-1-Gene Knockout Mice

OBJECTIVE: The anti-apoptotic protein Bax inhibitor-1 (BI-1) is a regulator of apoptosis linked to endoplasmic reticulum (ER) stress, and BI-1-/- mice exhibit increased sensitivity to tissue damage. The purpose of this study was to investigate the role of BI-1 in the pathogenesis of chronic mild stress (CMS)-induced depression-like behaviors in BI-1-/- mice. METHODS: We delivered CMS for 2 or 6 weeks in BI-1-knockout and wild-type mice. Control groups of BI-1-knockout and wild-type mice were left undisturbed. The measured parameters were sucrose consumption at weeks 1, 2, 3, 4, 5, and 6, spontaneous locomotion, and a forced swimming test (FST) at weeks 2 and 6. RESULTS: Significant decreases in sucrose consumption and increases in immobility time in the FST were observed in both stress groups compared with the non-stress groups. Interestingly, at week 2, but not at week 6, BI-1-/--stress mice showed less sucrose intake and greater immobility time than did BI-1+/+-stress mice. CONCLUSION: These results suggest that BI-1 may play role in protecting against the depressogenic effects of CMS in the short term, but not in the long term. Further study is required to deepen understanding of the role of BI-1 in protecting against depression.

Effects of Aripiprazole and Haloperidol on Fos-like Immunoreactivity in the Prefrontal Cortex and Amygdala

OBJECTIVE: Aripiprazole, a dopamine system stabilizer, shows efficacy against both negative symptoms and positive symptoms in patients with schizophrenia. The aim of this study was to investigate the effects of aripiprazole and haloperidol on c-FOS expression in rat brain. METHODS: Aripiprazole (1, 10 and 30 mg/kg, i.p.) and haloperidol (0.1 and 1 mg/kg, i.p.) were administered to adult Male Sprague-Dawley rats. After 2 h of drug or vehicle administration, the rats were killed and their brains were removed and perfused with fixative, then cut into 40 microm slices on a freezing microtome. Brain regions of interest were the medial prefrontal cortex (mPFC), the nucleus accumbens core and shell (NAC-C and NAC-S), the hippocampus (CA1, CA3 and DG), the central amygdala (Ce), the basolateral amygdala (BL) and the temporal cortex (Tc). Immunohistochemistry was performed to label cell bodies containing c-FOS. RESULTS: The administration of aripiprazole at all doses (1, 10 or 30 mg/kg) resulted in greater Fos-like immunoreactivity (FLI) in the investigated brain areas, as compared to the vehicle. Comparable increases in FLI were demonstrated in the NAC-C and NAC-S in response to both aripiprazole and haloperidol treatment. The administration of haloperidol (0.1 or 1 mg/kg) also resulted in greater FLI in the investigated brain areas, except the mPFC, where no changes were observed. In the Ce and BL, a significant increase in Fos-positive neurons was observed only with 0.1 mg/kg of haloperidol. CONCLUSION: Both aripiprazole and haloperidol increased FLI in limbic areas, which are considered important targets of antipsychotic drugs. The differential action of aripiprazole on FLI in the amygdala and mPFC as compared to haloperidol may be a good way to differentiate atypical from typical antipsychotics.

Potential infections of H5N1 and H9N2 avian influenza do exist in Guangdong populations of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Southeast China is one of the sites of influenza origin. During 2003--2004, nine avian influenza outbreaks took place in Guangdong Province. But no human case was reported. To examine the status of potential human infection by human influenza (H1N1, H3N2) and avian influenza (H5N1, H7N7, H9N2) in the avian influenza epidemic area of Guangdong Province, China, we conducted a seroepidemiologic survey in the people of this area from April to June of 2004.</p><p><b>METHODS</b>Three out of 9 H5N1 avian influenza affected poultry areas in Guangdong were randomly selected, and the population living within 3 kilometers of the affected poultries were chosen as the survey subjects. One thousand two hundred and fourteen people were selected from 3 villages at random. Human and avian influenza antibody titers were determined by hemagglutination-inhibition (HI) test and microneutralization test (MNT).</p><p><b>RESULTS</b>The positive rate of antibody to H5N1 was 3.03% in the occupational exposure group and 2.34% in general citizens group; that of H9N2 was 9.52% in the occupational exposure group and 3.76% in the general citizens group. Moreover one case in the occupational exposure group was positive for H7N7. One year later, all previously positive cases had become negative except for one H5N1-positive case.</p><p><b>CONCLUSION</b>The observations imply that H5N1 and H9N2 avian influenza silent infections exist in Guangdong populations.</p>

Change of Nuclear Factor-?B Signaling Pathway Alteration in Neonatal Rats with Early Hypoxic-Ischemic Reperfusion Brain Damage / 实用儿科临床杂志

Objective To explore the changes of genes associated with the nuclear factor of kappa B(NF-?B) signaling pathway in neonatal rats with early hypoxic-ischemic reperfusion brain damage(HIRBD).Methods Twenty-four SD rats at age of 7 days,with male to female of 1212,were randomized into normal control group(group A,n=8),hypoxic-ischemia reperfusion for 2 h(group B,n=8) and hypoxic-ischemia reperfusion for 4 h(group C,n=8).The tissues of hippocampus were taken for complete RNA extraction.Gene chip inspection and biological signal analysis technique were used to detect the expression of 113 involved signal molecules of NF-?B pathway.Results Compared with group A,the up-regulated expression was found in Chemokine(C-C motif) ligand 2,Dual specificity phosphatase 1,FBJ osteosarcoma oncogene(Fos) and Toll-like receptor 9.Whereas the expressions of Caspase-1,8,Mitogen-activated protein kinase kinase 6,Mitogen activated protein kinase 3 and Ras homolog gene family member a from Ras-gene famimly was found down-regulated in group B.The up-regulated expression was in Fos,IL-1? and Toll-like receptor 6,but that of down-regulation was found in Caspase-1,Extracellular matrix protein 1,Lysophosphatidic Acid G-protein-coupled receptor 2,Mucosa associated lymphoid tissue lymphoma translocation gene 1,Inhibitor of kappa B kinase epsilon and Ras homolog gene family member c.Conclusions At the early stage of HIRBD,the Toll-like receptors may induce NF-?B activation,leading to the coordinated induction of multiple genes,which is involved in inflammatory,apoptosis and cell proliferation.Genes induced by NF-?B are responsible for the physiopathological process of early brain damage in neonatal rats with HIRBD.