Antibody-drug conjugates (ADCs) are antitumor drugs composed of monoclonal antibodies and cytotoxic payload covalently coupled by a linker. Currently, 15 ADCs have been clinically approved worldwide. More than 100 clinical trials at different phases are underway to investigate the newly developed ADCs. ADCs represent one of the fastest growing classes of targeted antitumor drugs in oncology drug development. It takes advantage of the specific targeting of tumor-specific antigen by antibodies to deliver cytotoxic chemotherapeutic drugs precisely to tumor cells, thereby producing promising antitumor efficacy and favorable adverse effect profiles. However, emergence of drug resistance has severely hindered the clinical efficacy of ADCs. In this review, we introduce the structure and mechanism of ADCs, describe the development of ADCs, summarized the latest research about the mechanisms of ADC resistance, discussed the strategies to overcome ADCs resistance, and predicted biomarkers for treatment response to ADC, aiming to contribute to the development of ADCs in the future.

Objective To explore the correlation between HbA1c level and carotid plaque stability in type 2 diabetes mellitus(T2DM)patients.Methods From October 2018 to October 2020,100 T2DM patients who visited our hospital and underwent carotid artery ultrasound examination with a plaque thickness greater than 1.5 mm were included in this study.According to HbA1c levels,they were divided into HbA1c≤7%group(n=21),7%9%group(n=51).Results The FPGs of the 7%9%groups were higher than that of the HbA1c≤7%group(P<0.01).The plaque thickness gradually increased from group HbA1c≤7%,7%9%groups(P<0.01),and the proportion of high-level enhancement in the overall,proximal,middle,and distal segments of the plaque increased in sequence(P<0.05 or P<0.01).Pearson correlation analysis showed that HbA1c,FPG,and 2 hPG were positively correlated with plaque thickness and length(P<0.05).Spearman correlation analysis showed that HbA1c was positively correlated with the smoothness of the plaque surface,the presence of extremely low echogenicity within the plaque,and the overall,proximal,central,and distal enhancement intensity of the plaque(P<0.05).Conclusion HbA1c can not only evaluate the blood glucose control of T2DM patients,but also has a certain correlation with the stability of carotid plaque,with a trend of poorer plaque stability as HbA1c increases.

Amyloidosis is a metabolic disease characterized by the deposition of amyloidogenic fibrils in multiple organs, which causes structural disorders, leading to a decline in organ function and in the case of myocardial involvement, damage to the structure and function of the heart, which is the main cause of mortality. However, the disease is often misdiagnosed or underdiagnosed due to its insidious onset and lack of specificity in clinical manifestations. 99Tc m-pyrophosphate (PYP) SPECT is a noninvasive test that can not only identify cardiac amyloid deposits at an early stage but also provide a useful tool for the diagnosis of cardiac amyloidosis. This article briefly describes the traditional screening methods for cardiac amyloidosis, outlines their limitations, and focuses on the clinical diagnostic value of 99Tc m-PYP SPECT in cardiac amyloidosis.

OBJECTIVE To study the improvement effect and mechanism of Gastrodia elata active ingredient 3，4- dihydroxybenzaldehyde （3，4-DD） on oxygen-glucose deprivation/reoxygenation（OGD/R） injury in rat primary brain microvascular endothelial cells （BMECs）-rat adrenal chromaffin cells PC12 co-culture system. METHODS The co-culture model of BMECs and PC12 cells was replicated in the Transwell chamber， and divided into control group， model group， butylphthalide group （positive control group， 0.1 mmol/L） and 3，4-DD group （0.1 μmol/L）. OGD/R injury model of the co-culture system was induced in those groups except for the control group. After preventively intervention in BMECs with relevant medicine or culture medium for 24 h， cell transendothelial electronic resistance （TEER） value， lactate dehydrogenase （LDH） activity， brain-derived neurotrophic factor （BDNF） level and mRNA expressions of TrkB， Plc-γ， Map-2， GAP-43 in PC12 cells was detected. RESULTS Compared with the control group， TEER of the co-culture model， LDH activity and BDNF level of PC12 cells were decreased significantly in the model group （P＜0.01）， while mRNA expressions of TrkB， Plc-γ， Map-2 and GAP-43 in PC12 cells were increased significantly （P＜0.01）. Compared with the model group， TEER of the co-culture model， LDH activity， BDNF level， and the mRNA expressions of TrkB， Plc-γ， Map-2 and GAP-43 in PC12 cells were increased significantly in the 3，4-DD group and butylphthalide group （P＜0.05 or P＜0.01）. CONCLUSIONS 3，4-DD can relieve the damage of neuronal OGD/R by acting on BMECs， the mechanism of which may be associated with activating the BDNF/TrkB signaling pathway.

ObjectiveTo compare the effects of topical application of Modified Sanhuang Powder （加味三黄散， MSP） combined with cold compression versus cold compression alone on swelling and pain after knee arthroscopy through a retrospective cohort study. MethodsMedical records of 134 patients with knee arthroscopy-induced knee swelling and pain were divided into non-exposure group （51 cases） and exposure group （83 cases） based on whether they used MSP for external application after surgery. The non-exposure group received simple cold compression therapy in addition to functional exercise and routine treatment after surgery， while the exposure group received topical MSP on the basis of what were given in the non-exposure group. The Visual Analog Scale （VAS） scores were compared between the two groups before and 7 days after treatment， and knee swelling measurements were taken before and 3， 5， and 7 days after treatment. The clinical effective rate was compared between the two groups. ResultsThe VAS scores in both groups were lower after treatment （P＜0.05）， and the exposure group had lower scores than the non-exposure group （P＜0.05）. On the 3rd， 5th， and 7th days of treatment， the scores on swelling at 2 cm above the superior pole of the patella， at the midline of the patella， and 5 cm below the inferior pole of the patella significantly decreased after treatment in both groups （P＜0.05）， and the exposure group had lower scores than the non-exposure group （P＜0.05）. The total clinical effective rate in the exposure group was 91.56% （76/83）， which was higher than 78.43% （40/51） in the non-exposure group （P＜0.05）. ConclusionTopical application of MSP combined with cold compression is effective in relieving postoperative swelling and pain after knee arthroscopy and is superior to cold compress alone.

COVID-19 has swept globally and Pakistan is no exception.To investigate the initial introductions and transmissions of the SARS-CoV-2 in Pakistan,we performed the largest genomic epidemiology study of COVID-19 in Pakistan and generated 150 complete SARS-CoV-2 genome sequences from samples collected from March 16 to June 1,2020.We identified a total of 347 mutated positions,31 of which were over-represented in Pakistan.Meanwhile,we found over 1000 intra-host single-nucleotide variants(iSNVs).Several of them occurred concurrently,indicating possible interactions among them or coevolution.Some of the high-frequency iSNVs in Pakistan were not observed in the global population,suggesting strong purifying selections.The genomic epidemiology revealed five distinctive spreading clusters.The largest cluster consisted of 74 viruses which were derived from different geographic locations of Pakistan and formed a deep hierarchical structure,indicating an extensive and persistent nation-wide transmission of the virus that was probably attributed to a signature mutation(G8371T in ORF 1ab)of this cluster.Further-more,28 putative international introductions were identified,several of which are consistent with the epidemiological investigations.In all,this study has inferred the possible pathways of introduc-tions and transmissions of SARS-CoV-2 in Pakistan,which could aid ongoing and future viral surveillance and COVID-19 control.

Objective:To evaluate the effects of vaccine switch on the levels of neutralizing antibody (NA) of poliovirus in children aged<12 years.Methods:Subjects aged<12 years from 9 districts in Fujian province were chosen by stratified cluster and complete random sampling method. Blood samples were collected for testing NA of poliovirus by microcell neutralization.Results:A total of 2 134 subjects aged<12 years were selected. The positive rate of NA against PVⅠand Ⅲ were 98.64% and 95.83%; and geometric mean titers (GMTs) were 1∶259.35 and 1∶105.14, respectively. The GMTs presented a trend of decreasing as age increased. Compared to trivalent oral poliovirus vaccine (tOPV), bivalent oral poliovirus vaccine (bOPV) and inactivated poliovirus vaccine (IPV) induced higher GMTs of NA against poliovirusⅠand Ⅲ respectively. Among 182 children aged<5 years, the positive rate of NA against PVⅠ, Ⅱ, Ⅲ were 97.25%, 76.37% and 92.86%. There were statistical differences among the three types ( χ2=44.44, P=0.000). The rate of NA against PVⅡwas significantly lower than those ofⅠand Ⅲ (Ⅱ vs. I: χ2=34.65, P=0.000; Ⅱ vs. Ⅲ: χ2=18.99, P=0.000). And the GMTs of NA against PV Ⅰ, Ⅱ, Ⅲ were 1∶368.96、1∶23.06 and 1∶183.10, which were significantly different ( F=156.54, P=0.000). The GMT of PVⅠwas the highest, PV Ⅲ was the second, PVⅡ was lowest (pairwise comparison showed values of P all were 0.000). The analysis of general linear model showed that the interval between the date of last immunization and the date of sample collection would affect the GMTs of PVⅠand Ⅲ, different vaccine models would affect only the GMT of PV Ⅰ. The age maybe was a confounding factor. But no factors would affect the GMT of PV Ⅱ. Conclusions:After the vaccine switch, the level of NA against PVⅠand PV Ⅲ were still maintaining high level, but the level of PVⅡamong children<5 years was at relatively low level, which indicated that the surveillance should be strengthened.

Objective:To study the genomic sequence of Coxsackievirus A8 (CV-A8) associated with hand, foot and mouth disease (HFMD) from 2013 to 2018 in China and to analyze the genetic evolution of each coding region of the full-length genome.Methods:The genome sequences of 11 CV-A8 strains isolated from patients with HFMD in different regions of China from 2013 to 2018 were determined. Sequence alignment and genetic evolution analysis were performed by Sequencher 5.0 and MEGA 7.0 software, etc.Results:Sequence alignment showed that the genome length of 11 CV-A8 strains ranged from 7 393 bp to 7 400 bp. There was no base insertion or deletion in the coding region compared with the prototype strain, but there were individual base insertion or deletion in the non-coding region. The nucleotide and amino acid similarities in the VP1 region of 11 CV-A8 strains were 78.3%-98.6% and 92.6%-99.7%, respectively, and the nucleotide and amino acid sequences identities with the CV-A8 prototype strain were 78.3%-98.2% and 92.6%-99.7%, respectively. Based on the phylogenetic analysis of VP1 region sequences, the CV-A8 can be divided into five genotypes: A, B, C, D and E. The 11 CV-A8 strains in this study belonged to genotypes C (1 strain), D (2 strains) and E (8 strains). The nucleotide and amino acid similarities of 11 CV-A8 full-length genomes were 81.3%-98.8% and 95.9%-99.5%, respectively. The phylogenetic tree of the P2 region showed that the eight E genotypes CV-A8 had the closest evolutionary distance with CV-A4, CV-A14, and CV-A16. The phylogenetic tree of the P3 region showed that the eight E genotypes CV-A8 had a close evolutionary distance with CV-A5, CV-A16, CV-A14 and CV-A4.Conclusions:The 11 CV-A8 stains in this study showed significant intra-genotype diversity in capsid region and recombinant diversity in non-capsid region which indicated that CV-A8 quasispecies were still undergoing dynamics variation. CV-A8 may become an important pathogen of HFMD and the monitoring of CV-A8 needs to be further strengthened.

Objecve To observe the clinical effect and safety of the Chinese medicine syndrome differentiation combined with HAART for the ADC(acquried immune deficiency syndrom dementia complex). Methods A total of 80 patients with ADC were divided into the treatment group and control group based on random number table, 40 in each group. The patients in the control group were treated by highly active anti-retrovital therapy (HAART). The patients in the treatment group were treated with TCM treatment on the based of the control group. Both groups received the treatment for 3 months.These outcomes were measured: TCM syndrome integral, mini mental state examination(MMSE), daily behavior scale(ADL), change of clinical stage, and adverse reactions. Results The effect rate of treatment group was 82.5%, which was significant higher than 65% of the control group (χ2=8.115,P=0.024). After the treatment, the ADL integral of the treatment group (37.69 ± 5.31vs.33.67 ± 5.16;t=2.528,P=0.021) was significantly higher than that before the treatment; and the ADL integral of the control group(36.96 ± 5.52vs.34.54 ± 4.98;t=2.747,P=0.027) was significantly higher than that before the treatment.But there was no significant difference between the two groups after the treatment (t=2.003,P=0.139). After the treatment, the MMSE integral of the treatment group (24.76 ± 4.43 vs.19.97 ± 5.46;t=1.006,P=0.013) was significantly higher than that before the treatment; the MMSE integral of the control group(24.65 ± 4.36 vs. 20.11 ± 4.87;t=1.035,P=0.014) was significantly higher than that before the treatment. But there was no significant difference between the two groups after the treatment (t=0.953, P=0.347).There was no significant difference between the two groups in the clinical stage change (phase1χ2=1.231,P=0.954; phase2χ2=2.726,P=1.053). There was no adverse reaction in the two groups during the treatment.Conclusions The Traditional Chinese medcine combined with HAART was better than HAART alonein the treatment of ADC.

AIM: To investigate the apoptosis and molecular mechanism of human hepatocellular carcinoma HepG2 cells induced by ginsenoside Rh4.METHODS: Human hepatocellular carcinoma HepG2 cells were treated with ginsenoside Rh4 at doses of 10, 20 and 40 μmol/L, and the inhibitory effect of ginsenoside Rh4 on HepG2 cell viability was measured by MTT assay.The apoptotic rate of HepG2 cells was analyzed by flow cytometry.The morphological changes of the HepG2 cells were observed by Hoechst 33258 and TUNEL staining.The expression of apoptosis-related proteins Bax, Bcl-2, caspase-3 and caspase-9 was determined by Western blot.RESULTS: Ginsenoside Rh4 promoted apoptosis of HepG2 cells in a dose-dependent manner.TUNEL and Hoechst 33258 staining showed that the cells appeared obvious shrinking, swelling and rupture after treated with ginsenoside Rh4 for 24 h.The results of Western blot showed that with the increasing concentrations of ginsenoside Rh4, the expression of pro-apoptotic proteins Bax, cleaved caspase-3 and caspase-9 increased, while anti-apoptotic protein Bcl-2 decreased gradually.CONCLUSION: Ginsenoside Rh4 induces apoptosis of human hepatocellular carcinoma HepG2 cells, and the main mechanism may be related to down-regulation of Bcl-2 and up-regulation of Bax, cleaved caspase-3, and caspase-9.