The continuous emergence of SARS-CoV-2 variants as well as other potential future coronavirus has challenged the effectiveness of current COVID-19 vaccines. Therefore, there remains a need for alternative antivirals that target processes less susceptible to mutations, such as the formation of six-helix bundle (6-HB) during the viral fusion step of host cell entry. In this study, a novel high-throughput screening (HTS) assay employing a yeast-two-hybrid (Y2H) system was established to identify inhibitors of HR1/HR2 interaction. The compound IMB-9C, which achieved single-digit micromolar inhibition of SARS-CoV-2 and its Omicron variants with low cytotoxicity, was selected. IMB-9C effectively blocks the HR1/HR2 interaction in vitro and inhibits SARS-CoV-2-S-mediated cell-cell fusion. It binds to both HR1 and HR2 through non-covalent interaction and influences the secondary structure of HR1/HR2 complex. In addition, virtual docking and site-mutagenesis results suggest that amino acid residues A930, I931, K933, T941, and L945 are critical for IMB-9C binding to HR1. Collectively, in this study, we have developed a novel screening method for HR1/HR2 interaction inhibitors and identified IMB-9C as a potential antiviral small molecule against COVID-19 and its variants.

Objective:To summarize the clinical features of X-linked lymphoproliferative syndrome type 2 (XLP-2) , especially the cases with inflammatory bowel disease (IBD) as the clinical phenotype.Methods:The clinical features and the course of diagnosis and treatment of a XLP-2 patient with IBD as the primary phenotype at the Department of Gastroenterology of the Third Affiliated Hospital of Guangzhou Medical University in May 2021 were analyzed retrospectively. Key words of "X-linked lymphoproliferative syndrome type 2" , "X-linked inhibitor of apoptosis protein deficiency" , "hemophagocytic syndrome" were used to retrieve associated literatures in PubMed, CNKI and Wanfang database between January 2006 and October 2021. Associated literatures including the patients diagnosed as the XLP-2 were summarized and reviewed.Results:A total of 90 articles and 215 patients were included. Among them, 207 were males and 8 were females. There were 183 (85.1%) patients with age of diagnosis less than 14 years old. Hemophagocytic syndrome (55.3%, 119/215) , splenomegaly (27.0%, 58/215) and IBD (26.0%, 56/215) were the common clinical phenotypes. There were 56 patients with IBD as the clinical phenotype, including 52 males and 4 females. The average age of onset was 6.4 (0, 31.0) years old, the average age at diagnosis of IBD was 9.1 (0, 31.0) years old and the average age at diagnosis of XLP-2 was 10.8 (0, 41.0) years old. There were 49 of Crohn′s disease, 1 of ulcerative colitis and 6 of IBD unclassified. In the 56 patients with mutation of X-linked inhibitor of apoptosis protein ( XIAP) , nonsense mutations occurred in 26, missense mutations in 22 and deletion mutations in 8. In terms of treatment, 25 patients (44.6%) received hematopoietic stem cell transplantation, 8 (14.3%) received hormones, 11 (19.6%) received immunosuppressants, 27 (48.2%) received biologics, and 18 (32.1%) received 2 or more two biologics. Thirty-five patients were followed up for 8.46 (0.11, 34.00) years, 32 survived and 3 died. Conclusions:XLP-2 is an X chromosome recessive genetic disease, which is common in men and children. IBD is one of the common phenotypes. XLP-2 patients with IBD as phenotype mostly receive multiple drug treatments, and the disease has characteristics of refractory and delayed diagnosis. Early gene detection is of great significance for the differential diagnosis and early treatment of XIAP gene deficiency diseases.

Objective:To summarize the clinical features of X-linked lymphoproliferative syndrome type 2 (XLP-2) , especially the cases with inflammatory bowel disease (IBD) as the clinical phenotype.Methods:The clinical features and the course of diagnosis and treatment of a XLP-2 patient with IBD as the primary phenotype at the Department of Gastroenterology of the Third Affiliated Hospital of Guangzhou Medical University in May 2021 were analyzed retrospectively. Key words of "X-linked lymphoproliferative syndrome type 2" , "X-linked inhibitor of apoptosis protein deficiency" , "hemophagocytic syndrome" were used to retrieve associated literatures in PubMed, CNKI and Wanfang database between January 2006 and October 2021. Associated literatures including the patients diagnosed as the XLP-2 were summarized and reviewed.Results:A total of 90 articles and 215 patients were included. Among them, 207 were males and 8 were females. There were 183 (85.1%) patients with age of diagnosis less than 14 years old. Hemophagocytic syndrome (55.3%, 119/215) , splenomegaly (27.0%, 58/215) and IBD (26.0%, 56/215) were the common clinical phenotypes. There were 56 patients with IBD as the clinical phenotype, including 52 males and 4 females. The average age of onset was 6.4 (0, 31.0) years old, the average age at diagnosis of IBD was 9.1 (0, 31.0) years old and the average age at diagnosis of XLP-2 was 10.8 (0, 41.0) years old. There were 49 of Crohn′s disease, 1 of ulcerative colitis and 6 of IBD unclassified. In the 56 patients with mutation of X-linked inhibitor of apoptosis protein ( XIAP) , nonsense mutations occurred in 26, missense mutations in 22 and deletion mutations in 8. In terms of treatment, 25 patients (44.6%) received hematopoietic stem cell transplantation, 8 (14.3%) received hormones, 11 (19.6%) received immunosuppressants, 27 (48.2%) received biologics, and 18 (32.1%) received 2 or more two biologics. Thirty-five patients were followed up for 8.46 (0.11, 34.00) years, 32 survived and 3 died. Conclusions:XLP-2 is an X chromosome recessive genetic disease, which is common in men and children. IBD is one of the common phenotypes. XLP-2 patients with IBD as phenotype mostly receive multiple drug treatments, and the disease has characteristics of refractory and delayed diagnosis. Early gene detection is of great significance for the differential diagnosis and early treatment of XIAP gene deficiency diseases.

Objective:To construct a rat model of hypothalamic obesity by two point electrical damage to the ventromedial hypothalamus and arcuate nucleus.Methods:Twenty adult male SD rats of SPF grade were randomly divided into experimental group and sham operation group.A 25GA (0.45 mm) solid iron needle was used, the needle was coated with an insulating layer, and the tip exposed a 0.5 mm conductive area.With reference to The Rat Brain in Stereotaxic Coordinates and using the stereotactic instrument (AP: -2.6 mm, ML: ± 0.6 mm, DV: -9.6 mm) as the coordinate, 1.5 mA current was continuously applied for 25 s, the ventromedial nucleus (VMH) and arcuate nucleus (ARC) of bilateral brain in SD rats was damaged.During the experiment, the body weight(BW), food intake(FI) and water intake(WI) of the two groups were recorded regularly.The rats were sacrificed on the 28th day after the operation, and the changes of periprenal fat mass and body length were measured.The changes of liver and adipose tissue were detected by HE staining method, leptin by ELISA, leptin receptor(LEPR) by Western blot.Results:(1) The body weight of rats in the experimental group ((427.5±17.7)g) and weight gain ((208.5±14.8)g) were significantly increased compared with the rats in the control group((349.2±17.7)g), ((136.2±21.4)g)on the 28th day after operation ( t=7.661, 6.806, both P<0.001). (2) The daily food intake of rats in the experimental group ((44.2±6.6)g) on the 28th day after surgery was significantly higher than that in the control group ((23.0±3.6)g) ( t=6.918, P<0.001). There was no significant difference of the daily drinking water of rats between experimental group((37.5±12.1)ml) and the control group ((35.0±11.8)ml) ( t=0.361, P=0.726). (3) Perikidney fat mass of experimental group rats ((13.4±2.7)g) significantly increased 28 days after operation compared with control group rats((6.3±0.9)g)( t=4.250, P<0.05). The naso-anal length of experimental group((21.8±0.4)cm) was significantly decreased compared with the control group ((23.4±0.2)cm) ( t=-6.788, P<0.01). The Lee index of the experimental group (348.9±8.5) was significantly higher than that of the control group(305.5±4.3)( t=7.898, P<0.01). (4) The serum leptin content ((8 324.10±159.00)μg/L) of the experimental group rats at 28 days after surgery was significantly higher than that of the control group((2 705.31±407.10)μg/L) ( t=25.712, P<0.001). The lateral hypothalamus area (LHA) LEPR protein expression (1.3±0.1) in the experimental group was significantly higher than that in the control group (0.9±0.1) ( t=4.932, P<0.01). Conclusion:Two-point electrical damage to bilateral VMH and ARC of rats can establish hypothalamic obese rat model.

Objective:To compare long-term efficacy between watch and wait (W&W) strategy and total mesorectal excision (TME) in patients who were diagnosed with locally advanced rectal cancer (LARC) and attained clinical complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT).Methods:A retrospective cohort study was carried out. A total of 238 patients with stage II-III LARC exhibiting cCR after nCRT in Sun Yat-sen University Cancer Center from September 16, 2010 to January 9, 2018 were enrolled. Patients who were diagnosed with other malignant tumor within 5 years, did not receive regular follow-up in our center for more than 1 year and had no complete examination items after nCRT were excluded. Of 238 patients, 151 were male and 87 were female with a median age of 57 (27-83) years old. According to TNM stage, 61 cases were cII, 177 cases were cIII. Concurrent chemoradiotherapy (CCRT) was performed in 20 patients. CCRT plus induction/consolidated chemotherapy was performed in 218 patients. Intensity-modulated radiotherapy (IMRT) was applied to radiotherapy. The median radiation dose was 50 Gy/25 Fr for both the primary tumor and clinical target volumes, and the total dose was 45.0 to 50.6 Gy for 227 patients. In 27 patients, single-agent fluorouracil or capecitabine was used as concurrent chemotherapy. But in the other 211 patients, a combined regimen of oxaliplatin and fluorouracil or capecitabine was used. After nCRT, 59 and 179 patients received W&W (W&W group) and TME 6-12 weeks later (TME group), respectively. After the ending of treatment, patient was interviewed one time every 3 months and after 3 years, one time every six months. Overall survival (OS) rate, distant-metastasis-free survival (DMFS) rate, and local-recurrence-free survival (LRFS) rate were compared between two groups. The salvage treatment and sphincter preservation rate were analyzed. The survival curve was drawn with Kaplan-Meier method and evaluated by log-rank method.Results:In the cases treated with TME, the median interval from nCRT to surgery was 59 days. The postoperative pCR rate was 63.1%(113/179). The median follow-up time of the whole cohort was 41.8 (12.0-99.0) months. The 3-year and 5-year OS rates were 98.4% and 96.5%; the 3-year and 5-year LRFS rates were 96.5% and 96.5%; the 3- and 5-year DMFS rates were 91.0% and 87.9%, respectively. The 3-year OS rates in the W&W group and the TME group were 100% and 97.9%; the 5-year OS rates in W&W group and the TME group were 90.6% and 97.9% ( P=0.339); The 3-year local recurrence rate (LRR) in the W&W group was 12.9% (7 cases recurred within 2 years), which was significanthy higher then that in the TME group (0.6%, P=0.003). Salvage surgery was successful in 5/6 cases. After salvage surgery, LRFS rate was not significantly different between the two groups ( P=0.137). The 3-year DMFS rate in the W&W group and the TME group were 88.4% and 81.1%, whose difference was not significant ( P=0.593). Recurrence with simultaneous metastasis was seen in 3/7 cases of the W&W group. The sphincter was preserved in 89.8% (53/59) of patients in the W&W group, which was significantly higher than 73.7% (132/179) in the TME group ( P<0.001). When distance of tumor from the anal verge was ≤ 5 cm, the sphincter preservation rate (SPR) in the W&W group was 88.0% (44/50), which was significantly higher than the 54.4% (56/103) in the TME group ( P<0.001). Conclusions:W&W is safe and feasible for patients with LARC and cCR after nCRT. The results should be verified by further clinical trials.

Objective:To compare long-term efficacy between watch and wait (W&W) strategy and total mesorectal excision (TME) in patients who were diagnosed with locally advanced rectal cancer (LARC) and attained clinical complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT).Methods:A retrospective cohort study was carried out. A total of 238 patients with stage II-III LARC exhibiting cCR after nCRT in Sun Yat-sen University Cancer Center from September 16, 2010 to January 9, 2018 were enrolled. Patients who were diagnosed with other malignant tumor within 5 years, did not receive regular follow-up in our center for more than 1 year and had no complete examination items after nCRT were excluded. Of 238 patients, 151 were male and 87 were female with a median age of 57 (27-83) years old. According to TNM stage, 61 cases were cII, 177 cases were cIII. Concurrent chemoradiotherapy (CCRT) was performed in 20 patients. CCRT plus induction/consolidated chemotherapy was performed in 218 patients. Intensity-modulated radiotherapy (IMRT) was applied to radiotherapy. The median radiation dose was 50 Gy/25 Fr for both the primary tumor and clinical target volumes, and the total dose was 45.0 to 50.6 Gy for 227 patients. In 27 patients, single-agent fluorouracil or capecitabine was used as concurrent chemotherapy. But in the other 211 patients, a combined regimen of oxaliplatin and fluorouracil or capecitabine was used. After nCRT, 59 and 179 patients received W&W (W&W group) and TME 6-12 weeks later (TME group), respectively. After the ending of treatment, patient was interviewed one time every 3 months and after 3 years, one time every six months. Overall survival (OS) rate, distant-metastasis-free survival (DMFS) rate, and local-recurrence-free survival (LRFS) rate were compared between two groups. The salvage treatment and sphincter preservation rate were analyzed. The survival curve was drawn with Kaplan-Meier method and evaluated by log-rank method.Results:In the cases treated with TME, the median interval from nCRT to surgery was 59 days. The postoperative pCR rate was 63.1%(113/179). The median follow-up time of the whole cohort was 41.8 (12.0-99.0) months. The 3-year and 5-year OS rates were 98.4% and 96.5%; the 3-year and 5-year LRFS rates were 96.5% and 96.5%; the 3- and 5-year DMFS rates were 91.0% and 87.9%, respectively. The 3-year OS rates in the W&W group and the TME group were 100% and 97.9%; the 5-year OS rates in W&W group and the TME group were 90.6% and 97.9% ( P=0.339); The 3-year local recurrence rate (LRR) in the W&W group was 12.9% (7 cases recurred within 2 years), which was significanthy higher then that in the TME group (0.6%, P=0.003). Salvage surgery was successful in 5/6 cases. After salvage surgery, LRFS rate was not significantly different between the two groups ( P=0.137). The 3-year DMFS rate in the W&W group and the TME group were 88.4% and 81.1%, whose difference was not significant ( P=0.593). Recurrence with simultaneous metastasis was seen in 3/7 cases of the W&W group. The sphincter was preserved in 89.8% (53/59) of patients in the W&W group, which was significantly higher than 73.7% (132/179) in the TME group ( P<0.001). When distance of tumor from the anal verge was ≤ 5 cm, the sphincter preservation rate (SPR) in the W&W group was 88.0% (44/50), which was significantly higher than the 54.4% (56/103) in the TME group ( P<0.001). Conclusions:W&W is safe and feasible for patients with LARC and cCR after nCRT. The results should be verified by further clinical trials.

Objective To investigate the expression of peripheral programmed death (PD)-1hiCXCR5-CD4+T cells and its clinical significance in systemic lupus erythematosus (SLE). Methods Peripheral blood PD-1hiCXCR5-CD4+ T cells from 21 SLE patients and 16 healthy controls were examined by flow cytometry. The levels of serum anti-double-stranded deoxyribonucleic acid (dsDNA) antibodies were determined using immunoradiometric as-say. Data were analyzed with t test and Pearson's correlation test. Results The per-centages of PD-1hiCXCR5- cells within CD4+ T cell were significantly higher in SLE patients [(2.1 ±2.0)％] compared to normal controls [(0.3±0.3)％] (t=2.959, P<0.01). The percentages of PD-1hiCXCR5-cells within CD4+T cells in moderate to severe active SLE patients (3.0 ±2.0)％ was significantly increased compared to patients with mild or inactive (1.0±1.4)％(t=2.574, P<0.05) and normal controls (0.3±0.3)％ (t=5.149, P<0.01). The percentages of PD-1hiCXCR5- cells within CD4+ T cells from SLE patients were positively related with systemic lupus erythematosus disease activity index (SLEDAI) (r=0.475, P=0.0297). SLE patients in serum anti-dsDNA antibodies positive group (2.7±2.1)％displayed a higher percentage of PD-1hiCXCR5-cells within CD4+T cells than patients in serum anti-dsDNA antibodies negative group (0.6 ±0.5)％ (t=2.303, P<0.05). The percentages of PD-1hiCXCR5-cells within CD4+T cells from SLE patients were positively correlated with anti-dsDNA antibody titers. Conclusion The percentages of PD-1hiCXCR5- cells within CD4+ T cells from SLE patients are increased and are positively correlated with SLEDAI and anti-dsDNA antibody levels. Increased percentage of PD-1hiCXCR5-cells within CD4+T cells might play an important role in the pathogenesis of SLE.

Objective To explore the role of viral infection in the development of drug eruption in patients with HIV infection, and to evaluate the efficacy of antiviral treatment. Methods This study enrolled 87 HIV-positive patients, including 11 with and 76 without drug eruption, all of whom received highly active antiretroviral therapy(HAART). Clinical data on, baseline CD4+ and CD8+ T cell counts and CD4/CD8 ratio in these subjects were retrospectively analyzed. Results The severity of drug eruption was mild in the 11 HIV-positive patients, with a mean latency period of (14.00 ± 8.10)(range, 8 - 34)days. Of the 11 patients with drug eruption, 7 had liver function impairment, which was not in accordance with the severity of skin lesions. Drug eruption was controlled in all the 11 patients after anti-anaphylactic treatment without withdrawal of antiviral drugs. Compared with 75 HIV-positive patients without drug eruption, the 11 HIV-positive patients with drug eruption showed significantly increased baseline CD4 + T cell counts (493.00 ± 245.68 (range, 42 - 810)/μl vs. 347.81 ± 167.00 (range, 11 - 814)/μl, t = 647.50, P < 0.05), but decreased proportion of patients with baseline CD4+ T cell counts below the lower limit of normal(3/11 vs. 48/75(64.00%), X2 = 3.95, P < 0.05). There were no significant differences between 10 patients with drug eruption and 69 patients without drug eruption in the baseline CD8+ T cell count(1472.30 ± 858.55/μl vs. 1356.59 ± 684.06/μl, P > 0.05), CD4/CD8 ratio(0.40 ± 0.27 vs. 0.29 ± 0.16, P > 0.05), or percentage of patients with a CD4/CD8 ratio below the lower limit of normal (9/10 vs. 68/69 (98.55%), P >0.05). Conclusions The latency period of drug eruption seems to be long in HIV-positive patients receiving HAART, and mild drug eruption can be complicated by liver function impairment in the patients. Relatively high CD4 + counts may be a risk factor for the development and aggravation of drug eruption in HIV-positive patients.

Background Intracorneal macrophages play a critical role in corneal neovascularization (CNV)by secreting relative chemokines.But macrophages are characteristic by heterogeneity which has different biologic functions under different induction or stimulation from microenvironment.Objective This study was to detect the effects of chemokine (C-X3-C motif) ligand 1 (CX3CL1) and chemokine (C-C motif) ligand 2 (CCL2) on macrophages in vitro.Methods CNV was induced by corneal alkali burn in the left eyes of 20 male BALB/c mice aged 7-8 weeks.The CNV was evaluated under the slit lamp microscope 4 days after alkali burn,and then the corneal sections were prepared after mice were sacrificed.The expressions of CCR2 and CX3CR1 in the corneal specimens were detected by histo-fluorescence staining.Human peripheral blood mononuclear cells were separated using density gradient centrifugation and incubated in RPMI-1640 medium containing 10％ fetal bovine seruml(FBS) with 30 μg/L granulocyte-macrophage colony-stimulating factor (GM-CSF).The cells were divided into CD68 +CCR2 group and CD68+CX3CR1 group,and the percentage of the CX3CR1 and CCR2 expressions in the infiltrated macrophages of corneal specimens and human monocyte-derived macrophages was assayed by flow cytometry.The cultured cells were stimulated using human recombinant CX3CL1 and CCL2 proteins,and real-time PCR was used to detect the relative expressions of angiogenesis-related factors in macrophages.Results CNV was found in corneas 4 days after alkali burn and the CNV onsets from corneal limbus to central zone observed by a slit lamp.CCR2 and CX3CR1 were expressed in the F4/80-positive macrophages in alikali burned corneas.The macrophages grew for two weeks and appeared more dead cells in without GM-CSF group,but in GM-CSF induced group,the number of macrophages was increased.The percentage of CX3CR1-positive cells was 75％ and that of CCR2-positive cells was 45％.Real-time PCR showed that expression level of vascular endothelial growth factor (VEGF) mRNA increased and that ADAMTS-1 mRNA or TSP-1 mRNA decreased on macrophages after CCL2 stimulation,with significant differences in the 150 mg/L CCL2 group compared with the control group (t =-5.09,P =0.03 ; t =3.01,P =0.04 ; t =4.27,P =0.02).However,the VEGF mRNA expression decreased and ADAMTS-1 mRNA and TSP-1 mRNA increased after CX3CL1 stimulation,showing significant differences between the 150 mg/L CX3CL1 group and the control group (t=6.35,P=0.O2;t=-2.92,P=0.04; t=-3.81,P=0.03).Conclusions These results suggest that the macrophages have high heterogeneity.CCL2-and CX3CL1-expressing macrophages can regulate the expressions of angiogenesis-related factors.Macrophage chemokine signal may be a good target for treatment of neovascular ocular disease.

Objective:To investigate the correlation between plasma homocysteine (Hcy) concentration and transient ischemic attack (TIA) and traditional vascular risk factors.Methods:The plasma Hcy concentrations of 112 patients with TIA and 62 controls were measured by fluorescenee polarization immunoassay.Hcy concentrations and related risk factors were analyzed.Results:The risk of TIA was increased significantly in plasma Hcy concentration 10.0 to 14.9 μmol/L group(OR=2.450,95% CI 1.091 to 5.502) and≥15.0 μmol/L group(OR=5.169,95% CI 2.096 to 12.746) compared with plasma Hcy concentration＜10.0 μmol/L group.Using TIA as the dependent wariable,various vascular risk factors (including plasma Hcy concentration) as the independent variable,logistic regression was analyzed.The result showed that the risk of TIA was increased significantly in plasma Hcy concentration＞10.0 μmol/L group compared with plasma Hcy concentration＜10.0 μmol/L group(OR=3.150,95% CI 1.380 to 7.192).Conclusions:Plasma Hcy concentration is an independent risk factor for TIA.