Sleep disorders are becoming a social problem that poses a danger to human health and an obstacle to economic development.As an endogenous hormone,melatonin plays an important role in regulating circadian rhythm.Research has shown that exogenous melatonin holds promising prospects in the treatment of insomnia disorders and thus merits in-depth exploration and development.Given the close relationship between pharmacokinetic properties and drug efficacy as well as toxicity,this paper reviews the quantitative analysis methods for melatonin and its major metabolites,especially the pretreatment methods for biological samples and the related LC-MS/MS analysis methods.Studies related to the absorption,distribution,metabolism,excretion and drug-drug interactions of melatonin both in vivo and in vitro,as well as the level and species differences of endogenous melatonin are also outlined.Meanwhile,the druggability of melatonin and corresponding solutions are explored in the hope of providing data for the development of exogenous melatonin into novel sleep-regulating drugs.

OBJECTIVE To establish a liquid chromatography massspectrometry(LC-MS/MS)method for quantitatively determining the concentration of cepharanthine in rat plasma and tissue samples after intravenous injection of cepharanthine hydrochloride.METHODS ①The LC-MS/MS method was adopted.A Phenomenex C18(3.0 mm×50 mm,2.6 μm)column was employed with a mobile phase consisting of 0.05%formic acid-2 mmol·L-1 ammonium acetate-water solution and 0.1%formic acid-acetonitrile solution under gradient elution at a flow rate of 0.6 mL·min-1.The determination was performed using positive ion multiple reaction monitoring mode assays:cepharanthine(m/z:607.3→365.1)and buspirone(IS)(m/z:386.4→122.2).② Blood samples were collected from 6 SD rats at different time points following a single iv administration of cepharanthine to determine the concentration of the drug.The main pharmacokinetic parameters were calculated using a non-compartmental model.③72 SD rats were subjected to tissue distribution experiments after a single and multiple iv administra-tion of cepharanthine,and tissue samples were collected at six different time points(n=6)for the quanti-fication of drug concentrations.④ The whole blood plasma distribution ratio(Rb/p)of cepharanthine hydrochloride(7.5 mg·kg-1)in 3 SD rats was determined 2 h after iv administration.⑤The protein binding of cepharanthine to rat plasma and lung tissue homogenates was determined by equilibrium dialysis before the concentration of the free drug within the lungs was calculated.RESULTS ① An LC-MS/MS method for quantitatively determining cepharanthine in rat plasma and tissue homogenates was devel-oped,which demonstrated an excellent linear relationship(r2>0.999)within the concentration range of 2 to 1000 μg·L-1,with a lower limit of quantification at 2 μg·L-1.The obtained results met all the require-ments for accurate quantitative detection.②The main pharmacokinetic parameters of cepharanthine in rats following a single iv administration were as follows:C0=(686.91±238.43)μg·L-1,t1/2=(29.70±6.29)h,Vz=(62.70±7.93)L·kg-1,Vss=(62.55±11.28)L·kg-1,CL=(1.50±0.23)L·h-1·kg-1 and AUC(0-t)=(4.52±0.61)h·mg·L-1.③ Concentrations in tissues exceeded those in plasma after both a single and multiple iv administration,with the highest levels in the lung.The values of AUC(0-t)in lungs were(2 547.35±156.56)and(4 481.35±479.21)h·mg·L-1 after a single and multiple iv administration,respectively.④ The content of cepharanthine in blood cells was higher than that in plasma,and Rb/p was 3.5±0.8.⑤ After correction by the protein-binding rate,the minimum concentration of free drugs in the lungs(95.04 μg·L-1)exceeded the reported antiviral activity threshold against coronaviruses(EC50=60.67 μg·L-1).CONCLUSION An LC-MS/MS method has been established to rapidly and sensitively determine the concentration of cepharanthine in rat plasma and tissues.Following intravenous administration of ceph-aranthine hydrochloride,the pulmonary exposure level of the drug is significantly higher in plasma and other tissues,providing data for evaluating its in vivo pharmacological activities.

Sleep disorders are becoming a social problem that poses a danger to human health and an obstacle to economic development.As an endogenous hormone,melatonin plays an important role in regulating circadian rhythm.Research has shown that exogenous melatonin holds promising prospects in the treatment of insomnia disorders and thus merits in-depth exploration and development.Given the close relationship between pharmacokinetic properties and drug efficacy as well as toxicity,this paper reviews the quantitative analysis methods for melatonin and its major metabolites,especially the pretreatment methods for biological samples and the related LC-MS/MS analysis methods.Studies related to the absorption,distribution,metabolism,excretion and drug-drug interactions of melatonin both in vivo and in vitro,as well as the level and species differences of endogenous melatonin are also outlined.Meanwhile,the druggability of melatonin and corresponding solutions are explored in the hope of providing data for the development of exogenous melatonin into novel sleep-regulating drugs.

OBJECTIVE To establish a liquid chromatography massspectrometry(LC-MS/MS)method for quantitatively determining the concentration of cepharanthine in rat plasma and tissue samples after intravenous injection of cepharanthine hydrochloride.METHODS ①The LC-MS/MS method was adopted.A Phenomenex C18(3.0 mm×50 mm,2.6 μm)column was employed with a mobile phase consisting of 0.05%formic acid-2 mmol·L-1 ammonium acetate-water solution and 0.1%formic acid-acetonitrile solution under gradient elution at a flow rate of 0.6 mL·min-1.The determination was performed using positive ion multiple reaction monitoring mode assays:cepharanthine(m/z:607.3→365.1)and buspirone(IS)(m/z:386.4→122.2).② Blood samples were collected from 6 SD rats at different time points following a single iv administration of cepharanthine to determine the concentration of the drug.The main pharmacokinetic parameters were calculated using a non-compartmental model.③72 SD rats were subjected to tissue distribution experiments after a single and multiple iv administra-tion of cepharanthine,and tissue samples were collected at six different time points(n=6)for the quanti-fication of drug concentrations.④ The whole blood plasma distribution ratio(Rb/p)of cepharanthine hydrochloride(7.5 mg·kg-1)in 3 SD rats was determined 2 h after iv administration.⑤The protein binding of cepharanthine to rat plasma and lung tissue homogenates was determined by equilibrium dialysis before the concentration of the free drug within the lungs was calculated.RESULTS ① An LC-MS/MS method for quantitatively determining cepharanthine in rat plasma and tissue homogenates was devel-oped,which demonstrated an excellent linear relationship(r2>0.999)within the concentration range of 2 to 1000 μg·L-1,with a lower limit of quantification at 2 μg·L-1.The obtained results met all the require-ments for accurate quantitative detection.②The main pharmacokinetic parameters of cepharanthine in rats following a single iv administration were as follows:C0=(686.91±238.43)μg·L-1,t1/2=(29.70±6.29)h,Vz=(62.70±7.93)L·kg-1,Vss=(62.55±11.28)L·kg-1,CL=(1.50±0.23)L·h-1·kg-1 and AUC(0-t)=(4.52±0.61)h·mg·L-1.③ Concentrations in tissues exceeded those in plasma after both a single and multiple iv administration,with the highest levels in the lung.The values of AUC(0-t)in lungs were(2 547.35±156.56)and(4 481.35±479.21)h·mg·L-1 after a single and multiple iv administration,respectively.④ The content of cepharanthine in blood cells was higher than that in plasma,and Rb/p was 3.5±0.8.⑤ After correction by the protein-binding rate,the minimum concentration of free drugs in the lungs(95.04 μg·L-1)exceeded the reported antiviral activity threshold against coronaviruses(EC50=60.67 μg·L-1).CONCLUSION An LC-MS/MS method has been established to rapidly and sensitively determine the concentration of cepharanthine in rat plasma and tissues.Following intravenous administration of ceph-aranthine hydrochloride,the pulmonary exposure level of the drug is significantly higher in plasma and other tissues,providing data for evaluating its in vivo pharmacological activities.

Objective:To analyze the factors affecting delayed chemotherapy in children with Burkitt lymphoma (BL) and their influence on prognosis.Methods:Retrospective cohort study. Clinical data of 591 children aged ≤18 years with BL from May 2017 to December 2022 in China Net Childhood Lymphoma (CNCL) was collected. The patients were treated according to the protocol CNCL-BL-2017. According to the clinical characteristics, therapeutic regimen was divided into group A, group B and group C .Based on whether the total chemotherapy time was delayed, patients were divided into two groups: the delayed chemotherapy group and the non-delayed chemotherapy group. Based on the total delayed time of chemotherapy, patients in group C were divided into non-delayed chemotherapy group, 1-7 days delayed group and more than 7 days delayed group. Relationships between delayed chemotherapy and gender, age, tumor lysis syndrome before chemotherapy, bone marrow involvement, disease group (B/C group), serum lactate dehydrogenase (LDH) > 4 times than normal, grade Ⅲ-Ⅳ myelosuppression after chemotherapy, minimal residual disease in the interim assessment, and severe infection (including severe pneumonia, sepsis, meningitis, chickenpox, etc.) were analyzed. Logistic analysis was used to identify the relevant factors. Kaplan-Meier method was used to analyze the patients' survival information. Log-Rank was used for comparison between groups.Results:Among 591 patients, 504 were males and 87 were females, the follow-up time was 34.8 (18.6,50.1) months. The 3-year overall survival (OS) rate was (92.5±1.1)%,and the 3-year event-free survival (EFS) rate was (90.5±1.2)%. Seventy-three (12.4%) patients were in delayed chemotherapy group and 518 (87.6%) patients were in non-delayed chemotherapy group. The reasons for chemotherapy delay included 72 cases (98.6%) of severe infection, 65 cases (89.0%) of bone marrow suppression, 35 cases (47.9%) of organ dysfunction, 22 cases (30.1%) of tumor lysis syndrome,etc. There were 7 cases of chemotherapy delay in group B, which were seen in COPADM (vincristine+cyclophosphamide+prednisone+daunorubicin+methotrexate+intrathecal injection,4 cases) and CYM (methotrexate+cytarabine+intrathecal injection,3 cases) stages. There were 66 cases of chemotherapy delay in group C, which were common in COPADM (28 cases) and CYVE 1 (low dose cytarabine+high dose cytarabine+etoposide+methotrexate, 12 cases) stages. Multinomial Logistic regression analysis showed that the age over 10 years old ( OR=0.54,95% CI 0.30-0.93), tumor lysis syndrome before chemotherapy ( OR=0.48,95% CI 0.27-0.84) and grade Ⅲ-Ⅳ myelosuppression after chemotherapy ( OR=0.55,95% CI 0.33-0.91)were independent risk factors for chemotherapy delay.The 3-year OS rate and the 3-year EFS rate of children with Burkitt lymphoma in the delayed chemotherapy group were lower than those in the non-delayed chemotherapy group ((79.4±4.9)% vs. (94.2±1.1)%, (80.2±4.8)% vs. (92.0±1.2)%,both P<0.05). The 3-year OS rate of the group C with chemotherapy delay >7 days (42 cases) was lower than that of the group with chemotherapy delay of 1-7 days (22 cases) and the non-delay group (399 cases) ((76.7±6.9)% vs. (81.8±8.2)% vs. (92.7±1.3)%, P=0.002).The 3-year OS rate of the chemotherapy delay group (9 cases) in the COP (vincristine+cyclophosphamide+prednisone) phase was lower than that of the non-chemotherapy delay group (454 cases) ((66.7±15.7)% vs. (91.3±1.4)%, P=0.005). Similarly, the 3-year OS rate of the chemotherapy delay group (11 cases) in the COPADM1 phase was lower than that of the non-chemotherapy delay group (452 cases) ((63.6±14.5)% vs. (91.5±1.3)%, P=0.001). Conclusions:The delayed chemotherapy was related to the age over 10 years old, tumor lysis syndrome before chemotherapy and grade Ⅲ-Ⅳ myelosuppression after chemotherapy in pediatric BL. There is a significant relationship between delayed chemotherapy and prognosis of BL in children.

Objective To observe the effect of moxibustion of"Zusanli"and"Ganshu"on the intestinal flora of colorectal cancer cells liver metastasis in nude mice and its possible mechanism was explored.Methods HCT116-GFP colon cancer cells were inoculated by spleen injection,sixty SPF BALB/c male nude mice were divided into model control group,Pre-Mox group,Post-Mox group,Pre-Post-Mox group.Bilateral"Ganshu(BL18)"and"Zusanli(ST36)"acupoints were selected for moxibustion intervention for once a day for 10 minutes each time.the tumor formation rate,liver metastasis rate and the number of tumor of each group were calculated.Furthermore,16S rRNA analysis was used to assess their microbial diversity.Results Moxibustion intervention can significantly reduce the rate of liver metastasis,reduce the number of metastatic foci.Compared with the model control group,Lactobacillus_reuteri and Robinsoniella_peoriensis were significantly lower in Pre-Mox group(P<0.05).Lactobacillus_gasseri decreased significantly,Clostridium_cocleatum and Erysipelatoclostrdum_ramosum multiplex increased significantly in the Post-Mox group(P<0.01).Pre-Post-Mox mice had significantly decreased levels of Lactobacillus_gasseri,and Clostridium_cocleatum,Akkermansia_muciniphila and Clostridium_cocleatum were significantly increased(P<0.05).LEfSe Difference analysis showed that the Pre-Mox group was mainly changed by Coprobacillus;the Post-Mox group was marked by Muribaculaceae and erysipelas;the Pre-Post-Mox group took Verrucomicrobia,Akkermansia_muciniphila and erysipelas as signs.Conclusion Moxibustion could exert an inhibitory effect on CRC liver metastasis,especially the 5-week Pre-PostMox treatment showed the best inhibitory.The potential mechanism might rely on the alteration of microbiota diversity and composition.

Objective To observe the effect of moxibustion of"Zusanli"and"Ganshu"on the intestinal flora of colorectal cancer cells liver metastasis in nude mice and its possible mechanism was explored.Methods HCT116-GFP colon cancer cells were inoculated by spleen injection,sixty SPF BALB/c male nude mice were divided into model control group,Pre-Mox group,Post-Mox group,Pre-Post-Mox group.Bilateral"Ganshu(BL18)"and"Zusanli(ST36)"acupoints were selected for moxibustion intervention for once a day for 10 minutes each time.the tumor formation rate,liver metastasis rate and the number of tumor of each group were calculated.Furthermore,16S rRNA analysis was used to assess their microbial diversity.Results Moxibustion intervention can significantly reduce the rate of liver metastasis,reduce the number of metastatic foci.Compared with the model control group,Lactobacillus_reuteri and Robinsoniella_peoriensis were significantly lower in Pre-Mox group(P<0.05).Lactobacillus_gasseri decreased significantly,Clostridium_cocleatum and Erysipelatoclostrdum_ramosum multiplex increased significantly in the Post-Mox group(P<0.01).Pre-Post-Mox mice had significantly decreased levels of Lactobacillus_gasseri,and Clostridium_cocleatum,Akkermansia_muciniphila and Clostridium_cocleatum were significantly increased(P<0.05).LEfSe Difference analysis showed that the Pre-Mox group was mainly changed by Coprobacillus;the Post-Mox group was marked by Muribaculaceae and erysipelas;the Pre-Post-Mox group took Verrucomicrobia,Akkermansia_muciniphila and erysipelas as signs.Conclusion Moxibustion could exert an inhibitory effect on CRC liver metastasis,especially the 5-week Pre-PostMox treatment showed the best inhibitory.The potential mechanism might rely on the alteration of microbiota diversity and composition.

Various c-mesenchymal-to-epithelial transition (c-MET) inhibitors are effective in the treatment of non-small cell lung cancer; however, the inevitable drug resistance remains a challenge, limiting their clinical efficacy. Therefore, novel strategies targeting c-MET are urgently required. Herein, through rational structure optimization, we obtained novel exceptionally potent and orally active c-MET proteolysis targeting chimeras (PROTACs) namely D10 and D15 based on thalidomide and tepotinib. D10 and D15 inhibited cell growth with low nanomolar IC₅₀ values and achieved picomolar DC₅₀ values and >99% of maximum degradation (D_max) in EBC-1 and Hs746T cells. Mechanistically, D10 and D15 dramatically induced cell apoptosis, G1 cell cycle arrest and inhibited cell migration and invasion. Notably, intraperitoneal administration of D10 and D15 significantly inhibited tumor growth in the EBC-1 xenograft model and oral administration of D15 induced approximately complete tumor suppression in the Hs746T xenograft model with well-tolerated dose-schedules. Furthermore, D10 and D15 exerted significant anti-tumor effect in cells with c-MET^Y1230H and c-MET^D1228N mutations, which are resistant to tepotinib in clinic. These findings demonstrated that D10 and D15 could serve as candidates for the treatment of tumors with MET alterations.

ObjectiveTo develop a highly sensitive method for detection of mutation of FMS-like tyrosine kinase-3-tyrosine kinase domain(FLT3-TKD)of acute myeloid leukemia(AML)and apply to the monitor of minimal residual disease(MRD).MethodsRecombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed respectively and mixed at certain ratios.The obtained standard plasmids with mutation rates of 50%,1%,0.1% and 0% respectively were determined by restriction fragment length polymorphism(RFLP)in combination with Sanger method.The plasmid DNA standards and blood DNA standards,at various FLT3-D835Y mutation rates,were determined by the developed method to verify the sensitivity.The genomic DNA samples of patients with AML before and after treatment were determined by the developed method to monitor the MRD.ResultsSequencing proved that both the recombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed correctly.The sensitivity of developed method increased to 0.1% through Sanger method combined with digestion with EcoR Ⅴ/Xho Ⅰ and recovery of mutant fragments in determination of purified plasmid DNA and collected blood DNA samples.MRD was detected in the peripheral blood sample of a patients with AML in complete remission period by the developed method but not by Sanger method.ConclusionA highly sensitive method for detection of FLT3-TKD mutation was developed,which was of an important clinical significance in guiding the treatment of AML and monitoring the MRD in complete remission period.