The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious impact on global public health and the economy. SARS-CoV-2 infiltrates host cells via its surface spike protein, which binds to angiotensin-converting enzyme 2 on the host cell membrane. As a result, small molecules targeting spike protein have emerged as a hotspot in anti-SARS-CoV-2 drug research. Activity screening is an important step in seeking small molecule drugs. Therefore, this article aims to review the biological activity evaluation methods of small molecule inhibitors targeting SARS-CoV-2 spike protein, with the goal of laying the foundation for the discovery of new anti-SARS-CoV-2 drugs.

Otolaryngology ; Periodicals as Topic ; Quality of Life ; Sickness Impact Profile

To establish a MacELISA method for the detection of IgM antibodies against Chikungunya virus (CHIKV), we prepared virus like particle (VLP) antigens of CHIKV using the whole structural protein C-E3-E2-6K-E1 encoding gene with a baculovirus expression system in Sf9 insect cells. The VLPs were purified and used to immunize Kunming mice. Then, polyclonal antibodies were purified from the samples of ascites with a protein G HiTrap SP column and labeled with horseradish peroxidase. A MacELISA method for the detection of IgM antibodies against CHIKV was assembled with goat anti-human IgM antibody, VLP antigens and an enzyme-labeled polyclonal antibody. The results were evaluated with a serum panel containing serum samples from laboratory-confirmed CHIK, HFRS patients, healthy donors, and commercially available CHIKV IgM as a quality control. It was shown that the MacELISA had a specificity of 99% (99/100), the coefficients of variation (CoV) within a plate were <10%, and the CoV of different ELISA plates in terms of the plate variation coefficient was <15%. A comparative analysis was performed to compare the current method against a commercial CHIKV IgM antibody detection kit for IIFA-IgM. The detection limit of MacELISA was significantly lower than that of the IIFA-IgM commercial kit (P< 0.0001). Here, we demonstrate that the VLP-based MacELISA is a promising tool for the early diagnosis and epidemiological investigation of CHIKV infection, with a high level of sensitivity and specificity for the detection of IgM antibodies against CHIKV.
Animals ; Antibodies, Viral ; blood ; Chikungunya Fever ; blood ; diagnosis ; virology ; Chikungunya virus ; immunology ; isolation & purification ; Enzyme-Linked Immunosorbent Assay ; methods ; Humans ; Immunoglobulin M ; blood ; Mice

Objective To compare the prophylactic efficacy of combination of ganciclovir and acy- clovir or acyclovir alone against cytomegalovirus pneumonia in renal transplant recipients.Methods A to- tal of 217 renal transplant recipient(124 men and 93 women;mean age,32 years;age range,16-72 years) were divided into 3 groups randomly.In 51 cases,acyclovir was taken orally at a dose of 400 mg,3/d,from the third d to 3 months after transplantation.In 74 cases,ganciclovir was administered at a dose of 250 mg/d intravenously from the 21st d to 27th d to replace Acyclovir.In 92 cases,no prophylaxis against eytomegalov- irus pneumonia was performed.All patients were followed 3 months after transplantation.Comparison of the incidence rates of cytomegalovirus pneumonia among the 3 groups was performed using Fisher's exact test. Results Cytomegalovirus pneumonia developed in 20 cases in the 3 groups,including 4 cases(5.4%) in combined use group,2 cases(3.9%)in acyclovir alone group,and 14 cases(15.2%)in control group. Significant difference existed between the 2 experimental and control groups(P＜0.05).However,no signifi- cant difference existed between the 2 experimental groups(P＞0.05).Of the 20 cases,17(85.0%)were cured,and 3 died of respiratory failure.Conclusions Ganciclovir and acyclovir have prophylactic effect a- gainst cytomegalovirus pneumonia in renal transplant recipients.These 2 medications are inexpensive,and the patients have good compliance.

OBJECTIVETo investigate the effect of enterostomy in treatment of locally advanced rectal carcinoma patients with combined chemoradiotherapy and operation.

METHODSClinical data from 51 cases of locally advanced rectal cancer patients treated with preoperative chemoradiotherapy and operation were analyzed.

RESULTSThirty-three patients (64.9%) got staging down of their cancer after preoperative chemoradiotherapy, and 21.6% of patients (11 cases) had complete pathologic response. Thirty-seven patients received enterostomy, including extraperitoneal sigmoidostomy (29 cases), defunctioning ileostomy (8 cases) and double colostomy (3 cases with colon obstruction during preoperative therapy). One case experienced parastomal hernia and one stomal stenosis and 2 cases parastomal infection after enterostomy. No death of enterostomy occurred.

CONCLUSIONColostomy can reduce the pressure of obstructed intestinal tract and contribute much to the preoperative chemoradiotherapy, ileostomy can protect the distal stoma from leakage in sphincter saving operation. Enterostomy could be selected when needed in the favor of locally advanced rectal cancer patients.

Adult ; Aged ; Chemotherapy, Adjuvant ; Combined Modality Therapy ; Enterostomy ; adverse effects ; methods ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Radiotherapy, Adjuvant ; Rectal Neoplasms ; pathology ; surgery ; therapy ; Rectum ; drug effects ; radiation effects ; surgery ; Treatment Outcome

BACKGROUNDVarious tissue engineering strategies have been developed to facilitate axonal regeneration after spinal cord injury. This study aimed to investigate whether neural stem cells (NSCs) could survive in poly(L-lactic-co-glycolic acid) (PLGA) scaffolds and, when cografted with Schwann cells (SCs), could be induced to differentiate towards neurons which form synaptic connection and eventually facilitate axonal regeneration and myelination and motor function.

METHODSNSCs and SCs which were seeded within the directional PLGA scaffolds were implanted in hemisected adult rat spinal cord. Control rats were similarly injured and implanted of scaffolds with or without NSCs. Survival, migration, differentiation, synaptic formation of NSCs, axonal regeneration and myelination and motor function were analyzed. Student's t test was used to determine differences in surviving percentage of NSCs. One-way analysis of variance (ANOVA) was used to determine the differences in the number of axons myelinated in the scaffolds, the mean latency and amplitude of cortical motor evoked potentials (CMEPs) and Basso, Beattie & Bresnahan locomotor rating scale (BBB) score. The χ(2) test was used to determine the differences in recovery percentage of CMEPs.

RESULTSNSCs survived, but the majority migrated into adjacent host cord and died mostly. Survival rate of NSCs with SCs was higher than that of NSCs without SCs ((1.7831 ± 0.0402)% vs. (1.4911 ± 0.0313)%, P < 0.001). Cografted with SCs, NSCs were induced to differentiate towards neurons and might form synaptic connection. The mean number of myelinated axons in PLGA + NSCs + SCs group was more than that in PLGA + NSCs group and in PLGA group ((110.25 ± 30.46) vs. (18.25 ± 3.30) and (11.25 ± 5.54), P < 0.01). The percentage of CMEPs recovery in PLGA + NSCs + SCs group was higher than in the other groups (84.8% vs. 50.0% and 37.5%, P < 0.05). The amplitude of CMEPs in PLGA + NSCs + SCs group was higher than in the other groups ((1452.63 ± 331.70) µV vs. (428.84 ± 193.01) µV and (117.33 ± 14.40) µV, P < 0.05). Ipsilateral retransection resulted in disappearance again and functional loss of CMEPs for a few days. But contralateral retransection completely damaged the bilateral motor function.

CONCLUSIONSNSCs can survive in PLGA scaffolds, and SCs promote NSCs to survive and differentiate towards neurons in vivo which even might form synaptic connection. The scaffolds seeded with cells facilitate axonal regeneration and myelination and motor function recovery. But regenerating axons have limited contribution to motor function recovery.

Animals ; Axons ; physiology ; Cells, Cultured ; Electrophysiology ; Female ; Fluorescent Antibody Technique ; Lactic Acid ; chemistry ; Nerve Regeneration ; physiology ; Neural Stem Cells ; cytology ; Polyglycolic Acid ; chemistry ; Pregnancy ; Rats ; Rats, Wistar ; Schwann Cells ; cytology ; Spinal Cord Injuries ; therapy ; Tissue Engineering ; methods ; Tissue Scaffolds ; chemistry

OBJECTIVETo study the regulatory mechanism of SATB1 repression in cells other than T cells or erythroid cells, which have high expression level of SATB1.

METHODSHeLa epithelial cells were treated with either histone deacetylase inhibitor (HDACi) trichostatin A (TSA) or DNA methylation inhibitor 5-Aza-C before detecting SATB1 expression. Luciferase reporter system was applied to measure effects of EZH2 on SATB1 promoter activity. Over-expression or knockdown of EZH2 and subsequent quantitative reverse transcription-polymerase chain reaction were performed to determine the effect of this Polycomb group protein on SATB1 transcription. Chromatin immunoprecipitation (ChIP) assay was applied to measure enrichment of EZH2 and trimethylated H3K27 (H3K27me3) at SATB1 promoter in HeLa cells. K562 cells and Jurkat cells, both having high-level expression of SATB1, were used in the ChIP experiment as controls.

RESULTSBoth TSA and 5-Aza-C increased SATB1 expression in HeLa cells. Over-expression of EZH2 reduced promoter activity as well as the mRNA level of SATB1, while knockdown of EZH2 apparently enhanced SATB1 expression in HeLa cells but not in K562 cells and Jurkat cells. ChIP assay Results suggested that epigenetic silencing of SATB1 by EZH2 in HeLa cells was mediated by trimethylation modification of H3K27. In contrast, enrichment of EZH2 and H3K27me3 was not detected within proximal promoter region of SATB1 in either K562 or Jurkat cells.

CONCLUSIONSATB1 is a bona fide EZH2 target gene in HeLa cells and the repression of SATB1 by EZH2 may be mediated by trimethylation modification on H3K27.

Azacitidine ; pharmacology ; Base Sequence ; Cell Line ; Chromatin Immunoprecipitation ; DNA Methylation ; DNA Primers ; DNA-Binding Proteins ; physiology ; Enhancer of Zeste Homolog 2 Protein ; Epigenesis, Genetic ; physiology ; Epithelium ; metabolism ; Gene Silencing ; Humans ; Hydroxamic Acids ; pharmacology ; Matrix Attachment Region Binding Proteins ; genetics ; Polycomb Repressive Complex 2 ; Reverse Transcriptase Polymerase Chain Reaction ; Transcription Factors ; physiology

OBJECTIVETo investigate whether α-hemoglobin stabilizing protein (AHSP), the α-globin-specific molecular chaperone, is regulated by erythroid transcription factor NF-E2.

METHODSWe established the stable cell line with NF-E2p45 (the larger subunit of NF-E2) short hairpin RNA to silence its expression. Western blot, real-time polymerase chain reaction, and chromatin immunoprecipitation (ChIP) analysis were performed to detect the expression of AHSP, the histone modifications at AHSP gene locus, and the binding of GATA-1 at the AHSP promoter with NF-E2p45 deficiency. ChIP was also carried out in dimethyl sulfoxide (DMSO)-induced DS19 cells and estrogen-induced G1E-ER4 cells to examine NF-E2 binding to the AHSP gene locus and its changes during cell erythroid differentiation. Finally, luciferase assay was applied in HeLa cells transfected with AHSP promoter fragments to examine AHSP promoter activity in the presence of exogenous NF-E2p45.

RESULTSWe found that AHSP expression was highly dependent on NF-E2p45. NF-E2 bound to the regions across AHSP gene locus in vivo, and the transcription of AHSP was transactivated by exogenous NF-E2p45. In addition, we observed the decrease of H3K4 trimethylation and GATA-1 occupancy at the AHSP gene locus in NF-E2p45-deficient cells. Restoration of GATA-1 in G1E-ER4 cells in turn led to increased DNA binding of NF-E2p45.

CONCLUSIONNF-E2 may play an important role in AHSP gene regulation, providing new insights into the molecular mechanisms underlying the erythroid-specific expression of AHSP as well as new possibilities for β-thalassemia treatment.

Base Sequence ; Blood Proteins ; genetics ; DNA Primers ; GATA1 Transcription Factor ; physiology ; Gene Expression Regulation ; physiology ; Gene Silencing ; HeLa Cells ; Humans ; Methylation ; Molecular Chaperones ; genetics ; NF-E2 Transcription Factor, p45 Subunit ; physiology ; Promoter Regions, Genetic ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo explore the effect of combined preoperative chemotherapy with radiotherapy on locally advanced lower rectal carcinoma.

METHODSThirty- five patients with locally advanced lower rectal carcinoma were received a new regimen of combined preoperative chemotherapy with radiotherapy. Routine fr action of radiation was given with total dose of 46 Gy,2 Gy per fraction,five ti mes a week. Patients received oxaliplatin 130 mg/m(2) (infusion) on day 1, plus leu novorin 200 mg/m(2) and 5- FU 500 mg/m(2)(intravenous bolus) from day 1 to day 3 eve ry 3 weeks for total two cycles before irradiation. Operation was performed 4 to 6 weeks later after neoadjuvant therapy.

RESULTSAfter neoadjuvant therapy,all patients underwent surgical resection with complete pathologic response in 7 patients,average tumor size decrease of in 34.4%, tumor stage decrease in 65.7% o f patients and nodal- negative change rate of 55.6%. Radical resection was per formed in 34 patients,in whom 18 patients received abdominoperineal resection(AP R) and 16 patients received sphincter- preserving surgery with 45.7% of anal preservation rate. One patient received palliative resection. No local recurrence occurred in all patients who received radical resection,but two cases had liver metastasis.

CONCLUSIONCombined preoperative chemotherapy with radiotherapy is a better neoadjuvant therapy for lower advanced rectal cancer,which can decrease tumor stage,improve resectability and anal sphincter preservation rate,therefore ,this new neoadjuvant therapy with tolerable toxicity will has a promising application in the clinical setting.

Adult ; Aged ; Chemotherapy, Adjuvant ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Neoadjuvant Therapy ; Neoplasm Staging ; Radiotherapy, Adjuvant ; Rectal Neoplasms ; pathology ; surgery ; therapy ; Treatment Outcome

OBJECTIVETo investigate the expression of guanylin in colorectal cancer.

METHODSThe expression of guanylin was examined by RT-PCR and semiquantitative analysis in 20 cases of colorectal cancer, and its relationship with clinical characteristics was analyzed.

RESULTSThe positive expression of guanylin in normal tissue (80%, 16/20) was significantly higher than that in tumor tissue (35%, 7/20) (P<0.01). The same result was found in the semiquantitative analysis of 14 cases with differential expression. Differential expression of guanylin in colorectal cancer was associate with TNM stage (P<0.05), not with sex, Borrmann type and degree of differentiation (all P>0.05).

CONCLUSIONThere is differential expression of guanylin in colorectal cancer, and this kind of differential expression is associated with tumor TNM stage.

Colorectal Neoplasms ; metabolism ; pathology ; Female ; Gastrointestinal Hormones ; metabolism ; Humans ; Male ; Middle Aged ; Natriuretic Peptides ; metabolism ; Neoplasm Staging