Although teniposide(VM26)is widely used in the treatment of lymphoma,its poor water sol-ubility,low bioavailability and systemic toxicities still limit its clinical application.Nano-delivery systems are effective in increasing the bioavailability and reducing the toxicity of VM26,but there is an urgent need to overcome the problem of its non-specific targeting.Therefore,in this paper,we designed and constructed a hyaluronic acid-modified teniposide-targeted nano-delivery system(VM26-TNDS),and characterised its drug encapsulation rate,particle size and zeta potential.We also investigated the effects of VM26-TNDS on B-cell lymphoma cells with different expression of CD44 receptor,in terms of cellular targeting,inhibitory effect of proliferation,and induction of apoptosis and necrosis.The results showed that the drug encapsulation efficiency of VM26-TNDS exceeded 85％,and its liquid formulation could be stably stored at 4 ℃ for more than 6 months without precipitation.Based on CD44 receptor expression,Granta-519(high expression),Raji(medium-low expression)and SU-DHL-4(almost no expression)were screened for cellular experiments.Compared with VM26-NDS,the targeted modification could effec-tively reduce the uptake of VM26-TNDS by RAW264.7 and increase the uptake of VM26-TNDS by CD44 receptor-expressing lymphoma cells.The inhibitory proliferative effect and apoptotic necrosis-inducing a-bility of VM26-TNDS were stronger than those of VM26-NDS for Granta-519 and Raji cells,whereas there was no significant difference in the inhibitory effect on proliferation and ability to induce apoptosis and necrosis between VM26-NDS and VM26-TNDS in SU-DHL-4 cells,reflecting the targeting advantage for VM26-TNDS,as expected.However,its toxic effect on B-cell lymphoma cells only reflected the targeting advantage at some concentrations(0.25 μmol/L and 0.5 μmol/L),which met the expectation.The a-bove results indicate that a teniposide-targeted nano-delivery system,VM26-TNDS,has been successfully prepared in this study.VM26-TNDS improves the delivery efficiency of VM26 by targeting human B-cell lymphoma cells expressing the CD44 receptor,thus killing human B-cell lymphoma cells more effectively and overcoming the problem of non-specific targeting in drug delivery to improve the therapeutic effect.Its biological therapeutic effects and mechanisms still need to be proved by more in vitro and in vivo ex-perimental evidence.

Although teniposide(VM26)is widely used in the treatment of lymphoma,its poor water sol-ubility,low bioavailability and systemic toxicities still limit its clinical application.Nano-delivery systems are effective in increasing the bioavailability and reducing the toxicity of VM26,but there is an urgent need to overcome the problem of its non-specific targeting.Therefore,in this paper,we designed and constructed a hyaluronic acid-modified teniposide-targeted nano-delivery system(VM26-TNDS),and characterised its drug encapsulation rate,particle size and zeta potential.We also investigated the effects of VM26-TNDS on B-cell lymphoma cells with different expression of CD44 receptor,in terms of cellular targeting,inhibitory effect of proliferation,and induction of apoptosis and necrosis.The results showed that the drug encapsulation efficiency of VM26-TNDS exceeded 85％,and its liquid formulation could be stably stored at 4 ℃ for more than 6 months without precipitation.Based on CD44 receptor expression,Granta-519(high expression),Raji(medium-low expression)and SU-DHL-4(almost no expression)were screened for cellular experiments.Compared with VM26-NDS,the targeted modification could effec-tively reduce the uptake of VM26-TNDS by RAW264.7 and increase the uptake of VM26-TNDS by CD44 receptor-expressing lymphoma cells.The inhibitory proliferative effect and apoptotic necrosis-inducing a-bility of VM26-TNDS were stronger than those of VM26-NDS for Granta-519 and Raji cells,whereas there was no significant difference in the inhibitory effect on proliferation and ability to induce apoptosis and necrosis between VM26-NDS and VM26-TNDS in SU-DHL-4 cells,reflecting the targeting advantage for VM26-TNDS,as expected.However,its toxic effect on B-cell lymphoma cells only reflected the targeting advantage at some concentrations(0.25 μmol/L and 0.5 μmol/L),which met the expectation.The a-bove results indicate that a teniposide-targeted nano-delivery system,VM26-TNDS,has been successfully prepared in this study.VM26-TNDS improves the delivery efficiency of VM26 by targeting human B-cell lymphoma cells expressing the CD44 receptor,thus killing human B-cell lymphoma cells more effectively and overcoming the problem of non-specific targeting in drug delivery to improve the therapeutic effect.Its biological therapeutic effects and mechanisms still need to be proved by more in vitro and in vivo ex-perimental evidence.

Objective:To investigate the action mechanism of formononetin(FN)in regulating T helper type 1(Th1)cell dif-ferentiation and macrophage polarization through JAK/STAT signaling pathways in a mouse model of experimental autoimmune prostati-tis(EAP).Methods:Forty non-obese diabetic(NOD)male mice were randomly divided into four groups:normal control,EAP model control,low-dose FN(LFN,50 mg/kg)and high-dose FN(HFN,100 mg/kg).The EAP model was established in the latter three groups by subcutaneous injection of prostate antigens(PAgs)combined with complete Freund's adjuvant(CFA).After modeling,the mice in the LFN and HFN groups were treated intragastrically with FN at 50 and 100 mg/kg/d,respectively,and those in the nor-mal and model controls groups with carboxymethylcellulose sodium(CMC-Na).At 42 days after treatment,all the animals were killed and relevant tissues collected for observation of the pathological changes in the prostate tissue by HE staining,detection of Th1 cell dif-ferentiation and macrophage polarization in the prostate by immunofluorescence double staining(labeling CD4 and interferon-γ[IFN-γ],inducible nitric oxide synthase[iNOS]and CD206),measurement of the ratio of Th1 cells/macrophages in the spleen by flow cy-tometry and the levels of IFN-γ and tumor necrosis factor-α(TNF-α)in the serum by ELISA,and determination of the expressions of phosphorylated(p)-Janus kinase(JAK)1,JAK1,p-JAK2,JAK2,p-signal transducer and activator of transcription(STAT1)in the prostate tissue by Western blot.Results:Compared with the model controls,the mice treated with low-and high-dose FN exhibited more orderly arrangement of glandular epithelial cells,significantly reduced prostatic tissue inflammation scores(P＜0.05),and de-creased proportion of Th1 cells and expression of M1 macrophages(P＜0.05),but increased expression of M2 macrophages in the prostate and spleen tissues(P＜0.05).Besides,the levels of inflammatory cytokines IFN-γ(P＜0.05)and TNF-α(P＜0.05)in the serum of the mice in the LFN and HFN groups were remarkably reduced,and so were the ratios of p-JAK1/JAK1,p-JAK2/JAK2 and p-STAT1/STAT1 in the prostate tissues at the molecular level(P＜0.05),indicating the therapeutic effect of FN on EAP by regu-lating JAK/STAT signaling pathways,promoting inflammation resolution,and restoring immune balance.Conclusion:FN alleviates EAP by inhibiting JAK/STAT signaling pathways and regulating Th1 cell differentiation and macrophage polarization.

A quartz crystal microbalance(QCM)-systematic evolution of ligands by the exponential en-richment(SELEX)technique was developed to screen out aptamers with high affinity for arsenic(Ⅲ).A random single strand DNA library was designed and fixed on the mercaptoethylamine-modified crystal plate with arsenic(Ⅲ)as the target,and the free aptamer was captured in the solution,and the QCM-SELEX screening method was constructed.After 6 rounds of screening,the secondary library was se-quenced with high throughput method,and the 6S1 dissociation coefficient Kd value was 0.36 μmol/L based on QCM resonance frequency.Using 6S1 as a probe,the QCM biosensor was constructed for the detection of arsenic(Ⅲ).The sensor has a good linear relationship in the range of 0.01 μmol/L～0.2μmol/L,and the detection limit of arsenic(Ⅲ)is 5.2 nmol/L(3σ),indicatinggood selectivity.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Recently,inductively coupled plasma mass spectrometry(ICP-MS)has shown great potential in the quantitative analysis of biomolecules due to its high sensitivity,high accuracy,anti-interference ability and multi-element detection capability.Elemental tags enable specific labeling of target biomolecules with element-reporter groups,playing a critical role in the performance of bioanalysis using ICP-MS.Antibodies are highly specific to antigens on cell surfaces and are one of the most commonly used targeted delivery vehicles.Traditional random chemical coupling methods are difficult to control the coupling sites and loading numbers of element reporters,which lead to heterogeneity of antibody conjugates,affecting the specific recognition and binding ability of antibodies and antigens,and thus reducing the targeting ability and quantitative accuracy.To solve these issues,site-specific coupling of antibodies with element reporter was studied in this work.By using peptide-mediated affinity labeling technology,a short chain DNA was specifically labeled to immunoglobulin G(IgG)antibody K248,and then DNA base complementary pairing was used to realize accurate assembly of monoclonal antibodies and Eu-modified phage MS2 capsid,resulting in the preparation of highly sensitive and selective element tags.This method overcame the heterogeneity problem of element tags caused by random coupling,and ensured the targeting specificity,affinity and signal amplification ability of element tags.The element tag prepared here showed a specificity to bind/label with epidermal growth factor receptor(EGFR)biomarker on the surface of cancer cells,realizing single cancer cell analysis using ICP-MS.

Acanthamoeba is an opportunistic pathogen that causes Acanthamoeba keratitis, granulomatous amoebic encephalitis, and other cutaneous diseases. The life cycle of Acanthamoeba consists of 2 stages of trophozoites and cysts. Under adverse environmental conditions, Acanthamoeba encysts, while the conditions become favorable for growth, it reverts to the trophozoite form. Acanthamoeba excystation is crucial for its proliferation and can lead to recurrent infections after incomplete treatment. To identify the factors involved in excystation, A. castellanii was subjected to either encystation- or excystation-inducing conditions, and gene expression profiles were compared using mRNA sequencing. A. castellanii samples were collected at 8 h intervals for analysis under both conditions. Differentially expressed gene analysis revealed that 1,214 and 1,163 genes were upregulated and downregulated, respectively, by more than 2-fold during early excystation. Five genes markedly upregulated in early excystation (ACA1_031140, ACA1_032330, ACA1_374400, ACA1_275740, and ACA1_112650) were selected, and their expression levels were confirmed via real-time PCR. Small interfering RNA (siRNA) targeting these 5 genes was transfected into Acanthamoeba and gene knockdown was validated through real-time PCR. The silencing of ACA1_031140, ACA1_032330, ACA1_374400, and ACA1_112650 inhibited excystation and suggested that these genes might be essential for excystation. Our findings provide valuable insights for suppressing Acanthamoeba proliferation and recurrence.

Acanthamoeba is an opportunistic pathogen that causes Acanthamoeba keratitis, granulomatous amoebic encephalitis, and other cutaneous diseases. The life cycle of Acanthamoeba consists of 2 stages of trophozoites and cysts. Under adverse environmental conditions, Acanthamoeba encysts, while the conditions become favorable for growth, it reverts to the trophozoite form. Acanthamoeba excystation is crucial for its proliferation and can lead to recurrent infections after incomplete treatment. To identify the factors involved in excystation, A. castellanii was subjected to either encystation- or excystation-inducing conditions, and gene expression profiles were compared using mRNA sequencing. A. castellanii samples were collected at 8 h intervals for analysis under both conditions. Differentially expressed gene analysis revealed that 1,214 and 1,163 genes were upregulated and downregulated, respectively, by more than 2-fold during early excystation. Five genes markedly upregulated in early excystation (ACA1_031140, ACA1_032330, ACA1_374400, ACA1_275740, and ACA1_112650) were selected, and their expression levels were confirmed via real-time PCR. Small interfering RNA (siRNA) targeting these 5 genes was transfected into Acanthamoeba and gene knockdown was validated through real-time PCR. The silencing of ACA1_031140, ACA1_032330, ACA1_374400, and ACA1_112650 inhibited excystation and suggested that these genes might be essential for excystation. Our findings provide valuable insights for suppressing Acanthamoeba proliferation and recurrence.

Acanthamoeba is an opportunistic pathogen that causes Acanthamoeba keratitis, granulomatous amoebic encephalitis, and other cutaneous diseases. The life cycle of Acanthamoeba consists of 2 stages of trophozoites and cysts. Under adverse environmental conditions, Acanthamoeba encysts, while the conditions become favorable for growth, it reverts to the trophozoite form. Acanthamoeba excystation is crucial for its proliferation and can lead to recurrent infections after incomplete treatment. To identify the factors involved in excystation, A. castellanii was subjected to either encystation- or excystation-inducing conditions, and gene expression profiles were compared using mRNA sequencing. A. castellanii samples were collected at 8 h intervals for analysis under both conditions. Differentially expressed gene analysis revealed that 1,214 and 1,163 genes were upregulated and downregulated, respectively, by more than 2-fold during early excystation. Five genes markedly upregulated in early excystation (ACA1_031140, ACA1_032330, ACA1_374400, ACA1_275740, and ACA1_112650) were selected, and their expression levels were confirmed via real-time PCR. Small interfering RNA (siRNA) targeting these 5 genes was transfected into Acanthamoeba and gene knockdown was validated through real-time PCR. The silencing of ACA1_031140, ACA1_032330, ACA1_374400, and ACA1_112650 inhibited excystation and suggested that these genes might be essential for excystation. Our findings provide valuable insights for suppressing Acanthamoeba proliferation and recurrence.

Acanthamoeba is an opportunistic pathogen that causes Acanthamoeba keratitis, granulomatous amoebic encephalitis, and other cutaneous diseases. The life cycle of Acanthamoeba consists of 2 stages of trophozoites and cysts. Under adverse environmental conditions, Acanthamoeba encysts, while the conditions become favorable for growth, it reverts to the trophozoite form. Acanthamoeba excystation is crucial for its proliferation and can lead to recurrent infections after incomplete treatment. To identify the factors involved in excystation, A. castellanii was subjected to either encystation- or excystation-inducing conditions, and gene expression profiles were compared using mRNA sequencing. A. castellanii samples were collected at 8 h intervals for analysis under both conditions. Differentially expressed gene analysis revealed that 1,214 and 1,163 genes were upregulated and downregulated, respectively, by more than 2-fold during early excystation. Five genes markedly upregulated in early excystation (ACA1_031140, ACA1_032330, ACA1_374400, ACA1_275740, and ACA1_112650) were selected, and their expression levels were confirmed via real-time PCR. Small interfering RNA (siRNA) targeting these 5 genes was transfected into Acanthamoeba and gene knockdown was validated through real-time PCR. The silencing of ACA1_031140, ACA1_032330, ACA1_374400, and ACA1_112650 inhibited excystation and suggested that these genes might be essential for excystation. Our findings provide valuable insights for suppressing Acanthamoeba proliferation and recurrence.