Objective:To investigate the feasibility of a three-dimensional no new U-Net (3D nnU-Net) deep learning (DL) network for the automatic segmentation of colorectal cancer (CRC) based on abdominal CT images.Methods:This was a cross-sectional study. From January 2018 to May 2023, a total of 2180 primary CRC patients, confirmed by pathology at the Guangdong Provincial Hospital of Traditional Chinese Medicine (center 1, n=777), Nanfang Hospital, Southern Medical University (center 2, n=732), and Sun Yat-sen Memorial Hospital (center 3, n=671), were enrolled in this retrospective study. The baseline abdominal CT examination of each patient was conducted using CT equipment from 7 different models across 4 vendors, at the 3 centers, encompassing both the arterial phase (AP) and venous phase (VP). Two radiologists manually delineated the volume of interest to circumscribe the entire tumors in dual-enhanced phase CT images. The CT data of CRC patients from center 1 and center 3 were merged and divided into a training set ( n=1 159) and a validation set ( n=289) using a weighted random method with a ratio of 4∶1. The patients from center 2 were used as an independent external test set ( n=732). The 3D nnU-Net segmentation model was trained and tested. Using manually annotated label data as the benchmark, segmentation performance of the model was evaluated based on different phases and tumor locations. The segmentation coverage rate (SCR), Dice similarity coefficient (DSC), recall (REC), precision (PRE), F1-score, and 95% Hausdorff distance (HD 95) were calculated. The mean manual segmentation time and the mean automatic time were compared using independent samples t-test. Results:In the independent external test set, the performance of the 3D nnU-Net model based on the AP CT images was superior to that based on the VP CT images. On the AP images, the SCR, DSC, REC, PRE, F1-score, and HD 95 were 0.865, 0.714, 0.716, 0.736, 0.714, and 27.228, respectively; on the VP images, they were 0.834, 0.679, 0.710, 0.675, 0.679, and 29.358, respectively. The model achieved the best performance on right-sided colon cancer, with SCR, DSC, REC, PRE, F1-score, and HD95 on the AP CT images at 0.901, 0.775, 0.780, 0.787, 0.775, and 21.793, respectively. Next were left-sided colon cancer and rectal cancer, while the segmentation performance for transverse colon cancer was the worst (SCR, DSC, REC, PRE, F1-score, and HD 95 were 0.731, 0.631, 0.641, 0.630, 0.631 and 38.721, respectively). The automatic segmentation time on a single phase was (1.0±0.3) min, while the manual segmentation time was (17.5±6.0) min ( t=128.24, P<0.001). Conclusions:After training and validating on a dataset from multiple centers with various CT scanner vendors, the 3D nnU-Net DL model demonstrates the capability to automatically segment CRC based on abdominal CT images, while also showcasing commendable robustness and generalization ability.

Objective:To analyze the effect of chlorpyrifos on the expression of autophagy related proteins in rat hippocampal neurons, and to explore the role of autophagy in central nerve injury caused by acute chlorpyrifos poisoning.Methods:In October 2018, 35 male clean grade SD rats were randomly divided into 7 groups according to the observation time point, namely 0.5 d, 1 d, 2 d, 3 d, 5 d and 7 d groups and the control group, with 5 rats in each group. Each observation group was given 81.5 mg/kg chlorpyrifos by gavage, and the control group was given olive oil by gavage. The general conditions and poisoning symptoms of rats were observed continuously after exposure. The expressions of autophagy related proteins Beclin1, P62/SQSTM1 and LC3 in hippocampus were detected by Western blot. The cell morphology and LC3 expression in brain were observed by immunohistochemical staining.Results:Western blot results showed that compared with the control group, the expression of Beclin1 protein in hippocampal neurons of rats in the 1 d, 2 d, and 3 d groups increased, while the expression of P62/SQSTM1 protein in the 0.5 d, 1 d, and 2 d groups decreased, and the expression of LC3 protein was decreased in the 2 d group, and the differences were statistically significant ( P<0.05) . The results of immunohistochemistry showed that the hippocampal neurons of rats in the 5 d group were arranged disorderly, and some nuclei contours disappeared, especially in the 7 d group. The LC3 protein was expressed in the cytoplasm, and the expression level gradually increased, reaching a peak on the second day. Conclusion:The early activation of autophagy in rats with acute chlorpyrifos poisoning may be involved in chlorpyrifos induced hippocampal neuronal injury.

Objective:To analyze the effect of chlorpyrifos on the expression of autophagy related proteins in rat hippocampal neurons, and to explore the role of autophagy in central nerve injury caused by acute chlorpyrifos poisoning.Methods:In October 2018, 35 male clean grade SD rats were randomly divided into 7 groups according to the observation time point, namely 0.5 d, 1 d, 2 d, 3 d, 5 d and 7 d groups and the control group, with 5 rats in each group. Each observation group was given 81.5 mg/kg chlorpyrifos by gavage, and the control group was given olive oil by gavage. The general conditions and poisoning symptoms of rats were observed continuously after exposure. The expressions of autophagy related proteins Beclin1, P62/SQSTM1 and LC3 in hippocampus were detected by Western blot. The cell morphology and LC3 expression in brain were observed by immunohistochemical staining.Results:Western blot results showed that compared with the control group, the expression of Beclin1 protein in hippocampal neurons of rats in the 1 d, 2 d, and 3 d groups increased, while the expression of P62/SQSTM1 protein in the 0.5 d, 1 d, and 2 d groups decreased, and the expression of LC3 protein was decreased in the 2 d group, and the differences were statistically significant ( P<0.05) . The results of immunohistochemistry showed that the hippocampal neurons of rats in the 5 d group were arranged disorderly, and some nuclei contours disappeared, especially in the 7 d group. The LC3 protein was expressed in the cytoplasm, and the expression level gradually increased, reaching a peak on the second day. Conclusion:The early activation of autophagy in rats with acute chlorpyrifos poisoning may be involved in chlorpyrifos induced hippocampal neuronal injury.

Since December 2019, the corona virus disease 2019 (COVID-19) caused by the 2019 novel coronavirus (2019-nCoV) has been reported in Wuhan, Hubei Province. Almost 70% of patients susceptible to 2019-nCoV are over age of 50 years, with extremely large proportion of critical illness and death of the elderly patients. Meanwhile, the elderly patients are at high risk of osteoporotic fractures especially osteoporotic vertebral compression fractures (OVCF). During the prevention and control of COVID-19 epidemic, orthopedists are confronted with the following difficulties including how to screen and protect OVCF patients, how to accurately diagnose and assess the condition of OVCF patients with suspected or confirmed COVID-19, and how to develop reasonable treatment plans and comprehensive protective measures in emergency and outpatient clinics. In order to standardize the diagnosis and treatment of patients with OVCF diagnosed with COVID-19, the authors jointly develop this expert consensus. The consensus systematically recommends the standardized emergency and outpatient screening and confirmation procedures for OVCF patients with suspected or confirmed COVID-19 and protective measures for emergency and outpatient clinics. Moreover, the consensus describes the grading and classification of OVCF patients diagnosed with COVID-19 according to the severity of illness and recommends different treatment plans and corresponding protective measures based on the different types and epidemic prevention and control requirements.

Objective:To investigate the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in the lung tissue of rats with acute diquat (DQ) poisoning and the distribution of diquat in lungs.Methods:Fifty-four fasted male Wistar rats were randomized into control group ( n=6) and exposure group ( n=48) . According to the time point, the exposure group was divided into 2 h, 4 h, 12 h, 1 d, 3 d, 7 d, 11 d and 14 d groups with 6 rats in each group. Exposure groups were administered 11.55 mg/kg DQ (1 ml/100 g BW) by single-dose of intragastric administration, while the control group rats were given normal saline. The histopathological changes of lung tissue of rats in each group were observed. The expression of nrf2 in lung tissue was detected by immunohistochemistry, and the diquat concentration in lungs was determined by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS) . Results:In the exposure group, DQ was detected in lungs on 2 hours after poisoning. The concentration of DQ in lung tissue decreased gradually over time, and there was no accumulation in lung tissue. The histopathological changes of lung tissue were not obvious in the early stage of poisoning. The injury was the most serious on the 3rd day, a large number of inflammatory cells could be seen in alveolar cavity and lung stroma, and the pathological injury of lung tissue began to be alleviated on the 7th day. The results of immunohistochemistry showed that Nrf2 was mainly expressed in the nucleus of pulmonery cells. The expression of Nrf2 in the exposure group was significantly higher than the control group. The expression of Nrf2 increased significantly at the 12th hour ( P<0.05) , reached the peak on the 3rd day ( P<0.05) . There was no difference between the control group and the 14th day ( P>0.05) . Conclusion:There was no accumulation of DQ in the lung tissue for a long time, and there was a hysteresis in lung injury induced by redox reaction of DQ. Nrf2 was highly expressed in the lung tissue of rats with acute DQ poisoning, which was correlated with histopathology injury of lung tissue, suggesting that Nrf2 plays an important role in antagonizing acute lung injury induced by DQ.

Objective:To investigate the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in the lung tissue of rats with acute diquat (DQ) poisoning and the distribution of diquat in lungs.Methods:Fifty-four fasted male Wistar rats were randomized into control group ( n=6) and exposure group ( n=48) . According to the time point, the exposure group was divided into 2 h, 4 h, 12 h, 1 d, 3 d, 7 d, 11 d and 14 d groups with 6 rats in each group. Exposure groups were administered 11.55 mg/kg DQ (1 ml/100 g BW) by single-dose of intragastric administration, while the control group rats were given normal saline. The histopathological changes of lung tissue of rats in each group were observed. The expression of nrf2 in lung tissue was detected by immunohistochemistry, and the diquat concentration in lungs was determined by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS) . Results:In the exposure group, DQ was detected in lungs on 2 hours after poisoning. The concentration of DQ in lung tissue decreased gradually over time, and there was no accumulation in lung tissue. The histopathological changes of lung tissue were not obvious in the early stage of poisoning. The injury was the most serious on the 3rd day, a large number of inflammatory cells could be seen in alveolar cavity and lung stroma, and the pathological injury of lung tissue began to be alleviated on the 7th day. The results of immunohistochemistry showed that Nrf2 was mainly expressed in the nucleus of pulmonery cells. The expression of Nrf2 in the exposure group was significantly higher than the control group. The expression of Nrf2 increased significantly at the 12th hour ( P<0.05) , reached the peak on the 3rd day ( P<0.05) . There was no difference between the control group and the 14th day ( P>0.05) . Conclusion:There was no accumulation of DQ in the lung tissue for a long time, and there was a hysteresis in lung injury induced by redox reaction of DQ. Nrf2 was highly expressed in the lung tissue of rats with acute DQ poisoning, which was correlated with histopathology injury of lung tissue, suggesting that Nrf2 plays an important role in antagonizing acute lung injury induced by DQ.

AIM: To investigate the role of hydrogen sulfide (H_2S) in the cholecystokinin octapeptide (CCK-8) attenuating lipopolysaccharide (LPS)-induced lung injury. METHODS: A rat model of lung injury induced by intravenous injection of LPS was developed. Male Wistar rats were divided into normal control group, LPS group, LPS+CCK-8 group and CCK-8 group. Six hours after LPS injection, partial pressure of oxygen in the arterial blood (PaO_2), H_2S content and cystathionine-γ-lyase (CSE) activity in lung tissue were detected. The mRNA expression of CSE in lung tissue was determined by RT-PCR;the structure of lung tissues was observed under optical microscope. RESULTS: Compared to normal control rats, the LPS-treated rats had significantly decreased PaO_2 level, increased index of quantitative assessment (IQA) score, while H_2S content, CSE activity and the mRNA expression of CSE in lung tissue were significantly increased (all P<0.05). Administration of CCK-8 into LPS-treated rats increased the PaO_2 level and alleviated the degree of lung injury (measured by IQA score). In addition, CCK-8 decreased H_2S content, CSE activity, and the mRNA expression of CSE (all P<0.05). No significant difference of the above-mentioned parameters between CCK-8 group and normal control group was observed. CONCLUSION: CCK-8 reduces LPS-induced lung injury through inhibiting the generation of endogenous H_2S.

AIM: To study the signal pathway involved in up-regulation of LPS-induced HO-1 expression by CCK-8. METHODS: Forty-two SD rats were divided into 7 groups (six rats each) randomly as follows: control group, LPS group, LPS+SP600125 (JNK-specific inhibitor) group, CCK-8+LPS group, CCK-8+LPS+SP600125 group, CCK-8 group and CCK-8 +SP600125 group. Lungs from the rats in these 7 groups were excised 6 h after the agents were administered. HO-1 mRNA expression was examined by RT-PCR. The protein expression of HO-1 was detected by Western blotting and immunofluorescence flow cytometry (FCM). RESULTS: There were significant positive expression of HO-1 mRNA in LPS group compared to control group. CCK-8 enhanced LPS-induced HO-1 mRNA expression and CCK-8 alone induced HO-1 mRNA expression as well. The mRNA expressions of HO-1 in LPS group, CCK-8+LPS group and CCK-8 group were 3.01 (P<0.01), 5.88 (P<0.01) and 3.45 (P<0.01) times as many as that in control group, respectively. SP600125 inhibited the mRNA expression of HO-1 induced by CCK-8 and (or) LPS. The change of HO-1 protein expression was in accordance with that of HO-1 mRNA expression by Western blotting and immunofluorescence FCM. CONCLUSION: These results suggest that JNK/c-Jun signal pathway plays an important role in the up-regulation of LPS-induced HO-1 expression by CCK-8.

AIM: To explore the role of NO/ inducible nitric oxide synthase (iNOS) in the metabotromi glutamate receptor 2/3C (mGluR2/3) mediated-brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP), and to observe the influences of α-methyl- (4-tetrazolyl- phenyl) glycine (MTPG), an antagonist of mGluR2/3, on the expression of iNOS during the induction of brain ischemic tolerance. METHODS: Thirty-six Sprague-Dawley rats were subjected to four vessel occluding global brain ischemic model. Thionin staining and immunohistochemistry were used for neuropathological evaluation and assay of iNOS expression in the hippocampal CA1 subregion of the rats. RESULTS: In the sham group, weak expression of iNOS was detected. The expression of iNOS in the CIP and CIP+ischemic insult groups were increased significantly compared with that in the sham group. Administration of MTPG via lateral cerebral ventricle 20 min before CIP blocked the up-regulation of iNOS induced by CIP, but had no influence on the pyramidal neuron survival. However, in the MTPG+CIP+ischemic insult group, the expression of iNOS was extremely intensive compared to that in CIP and MTPG+CIP groups. Importantly, this up-regulation was accompanied with obvious delayed neuronal death. CONCLUSION: NO/iNOS pathway plays an important role in the process of mGluR2/3 mediated-brain ischemic tolerance induced by CIP.

Objective To investigate the changes of neuroglobin (Ngb) expression in the CA1 hippocampus after cerebral ischemia and the effect of limb ischemic preconditioning (LIP) on it in young and aged rats. Methods SD rats aged 3 months and 21-23 months with permanently occluding bilateral vertebral arteries were randomly divided into cerebral ischemic group and LIP + cerebral ischemic group, respectively. The expression of Ngb mRNA and protein in the hippocampus were investigated by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot methods. The profile of delayed neuronal death (DND) of pyramidal neurons in the hippocampus CA1 was evaluated by using thionin staining under light microscope by determining the neuronal density (ND) and histological grade (HG). Results Ngb mRNA and protein expressions were 0.16±0.02 and 0.32±0.07, 0.52±0.04 and 0.91±0.06, 0.09±0.01 and 0.22±0.08, 0.21±0.01 and 0.66± 0. 06 in young cerebral ischemia group, LIP + young cerebral ischemia group, aged cerebral ischemia group and LIP + aged cerebral ischemia group, respectively. The expressions of Ngb mRNA and protein after cerebral ischemia for 8 minutes in aged rats were decreased compared with those in the young rats which suffered an identical cerebral ischemia with the aged rats (P<0.05). LIP up-regulated Ngb mRNA and protein expressions in both young and aged rats which suffered cerebral ischemia (P<0.05). However, the up-regulation of Ngb expression in aged rats was significantly less than that in young rats (P<0.05). Neuropathological evaluation showed that ND was 38.8±10.9, 171.5±16.9, 21.2±12.2 and 102.7±15.4 in young cerebral ischemic group, LIP + young cerebral ischemic group, aged cerebral ischemic group and LIP + aged cerebral ischemic group, respectively. It showed that obvious DND of pyramidal neurons was found in young and aged rats after cerebral ischemia. Although LIP effectively protected the pyramidal neurons in the CA1 hippocampus against DND normally induced by ischemic insult, the neuroprotection of LIP for aged rats was less effective than that for young rats. Conclusions The expression of Ngb and the up-regulation effect of LIP on the expression in aged rats are significantly decreased compared to those in young rats when the rats suffer cerebral ischemia. These differences may be one of underlying reasons why the aged rats exhibit severe DND after cerebral ischemia and why the neuroprotective effect of LIP is less in the aged rats than that in the young rats.