Research progress in pharmacokinetics and therapeutic drug monitoring of tyrosine kinase inhibitors in the treatment of gastrointestinal stromal tumors / 中国药房

Tyrosine kinase inhibitors （TKIs） represent a class of small-molecule targeted drugs that improve the survival time of patients with gastrointestinal stromal tumor （GIST）. Imatinib， sunitinib， regorafenib， ripretinib， and avapritinib are commonly used TKIs in the clinical treatment of various types of GIST. This article provides a comprehensive review of the pharmacokinetics and therapeutic drug monitoring （TDM） of these five drugs， finding that there is significant individual variability in the pharmacokinetics of these drugs. Among them， the absorption of imatinib， regorafenib， and avapritinib are influenced by food intake. Imatinib should be taken with meals and 200 mL of water， regorafenib is taken with a low-fat meal， while avapritinib is taken on an empty stomach. TKIs are mainly metabolized by cytochrome P450 3A4 （CYP3A4）， and when used in combination with CYP3A4 inducers or inhibitors， drug exposure levels will significantly change； apart from metabolic enzymes， the exposure levels of TKIs are also influenced by interactions with the transporter proteins P-glycoprotein and breast cancer resistance protein. Currently， research on TDM for TKIs is still in the exploratory stage， with a substantial amount of literature reporting the effective concentrations of imatinib， sunitinib and regorafenib. However， the precise relationship between exposure levels and efficacy/ toxicity needs further exploration. Currently， there is a lack of research on the correlation between exposure levels and efficacy/ toxicity of ripretinib and avapritinib. It is recommended to implement TDM in patients taking these drugs and explore their therapeutic window in combination with pharmacokinetic models. The commonly used methods for clinical TDM of TKIs include immunoassay， chromatography， and surface-enhanced Raman spectroscopy， providing a technical basis for clarifying the therapeutic window of TKIs.

Method establishment and clinical practice for concentration determination of caffeine and its metabolites in urine / 中国药房

OBJECTIVE To establish a method for concentration determination of caffeine and its three metabolites， theophylline， paraxanthine and theobromine in urine， and apply it in clinical practice. METHODS Using caffeine-13C3-d3 as internal standard （IS）， and the urine samples were protein precipitated with acetonitrile； HPLC-MS/MS method was adopted to determine the concentrations of caffeine and its three metabolites. The determination was performed on Waters ACQUITY UPLC® BEH HILIC column with mobile phase consisting of 60 mmol/L ammonium acetate （A）-acetonitrile （B） （gradient elution） at the flow rate of 0.5 mL/min. The column temperature was set at 38 ℃ ， and the sample size was 2 μL. The electrospray ionization detection was operated in a positive mode by multiple reaction monitoring. The detection ions for quantitative analysis were m/z 195.1→110.0 for caffeine， m/z 181.1→124.0 for theophylline， m/z 181.1→124.0 for paraxanthine， m/z 181.1→138.0 for theobromine， and m/z 198.1→ 140.1 for IS. The above method was used to determine the concentrations of caffeine and its three metabolites in the urine of 19 infants with apnea of prematurity （AOP）. RESULTS The linear ranges of mass concentration of caffeine， theophylline， paraxanthin and theobromine were 0.200-200， 0.050-50.0，0.050 0-50.0， and 0.100-100 μg/mL， respectively. The lower limits of quantification were 0.200， 0.050， 0.050 and 0.100 μg/mL （r＞0.990）， respectively. RSDs of intra-day and intra- day precision were not above 10.37%， and matrix factors were 85.68%-109.90%； extraction recoveries were 93.53%-109.40% （RSD≤15%）， and RSDs of stability tests were all lower than 15%. The concentrations of caffeine and its three metabolites in the urine of 19 cases were （27.346±7.951）， （0.351±0.223）， （0.428±0.395） and （0.472±0.374） μg/mL， respectively. CONCLUSIONS The established HPLC-MS/MS method is simple， sensitive and can be used for the determination of caffeine and its three metabolites in urine samples of AOP.

Clinical evidence-based guideline for the diagnosis and treatment of anterior cruciate ligament injury (2022 version) / 中华创伤杂志

The anterior cruciate ligament (ACL) injury is a common sports injury that has a significant impact on knee function and patients′ mobility. With the popularity of national fitness campaign in China, the incidence of ACL injury is increasing year by year. Currently, there still lacks clinical standards or guidelines on how to choose appropriate treatment methods, surgical plans and rehabilitation protocols for ACL injury. In order to timely reflect the new treatment concept of ACL injury, standardize its diagnosis and treatment and improve the curative effect, the Sports Medicine Society of Chinese Research Hospital Association and the Editorial Board of Chinese Journal of Trauma organized domestic orthopedic and sports medicine experts to formulate the "clinical evidence-based guideline for the diagnosis and treatment of anterior cruciate ligament injury (2022 version)" based on the level of evidence-based medicine and in compliance with the principle of scientificity, practicability and advancement. The present guideline includes 12 recommendations for the diagnosis, treatment and rehabilitation of ACL injury in order to provide guidance and assistance for the clinical diagnosis and treatment of ACL injury in China.

Establishment and application of a method for the determination of plasma protein binding rate of imatinib and its metabolite / 中国药房

OBJECTIVE To establish a method for the determination of plasma protein binding rate of imatinib and its metabolite（N-desmethyl imatinib ）and apply it to patients with gastrointestinal stromal tumor （GIST）.METHODS Using imatinib - d8 as the internal standard ，after being deproteinized methanol ，the sample was determined by equilibrium dialysis combined with liquid chromatography -tandem mass spectrometry . The free concentrations of imatinib and its metabolites in plasma of GIST patients were detected by the same method . RESULTS The protein binding rates of imatinib with albumin ，α1-acid glycoprotein and globulin at 120 ng/mL and 4 000 ng/mL were （92.5±1.0）% and（91.7±0.4）%，（56.6±2.0）% and（62.6±2.6）%，（56.3±3.1）% and （68.0±8.6）% ，respectively. The protein binding rates of N-desmethyl imatinib with albumin ，α1-acid glycoprotein and globulin at 60 ng/mL and 2 000 ng/mL were （90.6±3.5）% and（91.3±1.5）%，（54.1±5.1）% and（63.7±1.3）%，（56.2±7.6）% and（67.5±7.3）%，respectively. Compared with the low concentration group of imatinib （120 ng/mL）and its metabolite （60 ng/mL），the plasma protein binding rate of high concentration of imatinib （4 000 ng/mL）and its metabolite （2 000 ng/mL）with α1-acid glycoprotein and globulin was significantly increased （P＜ Δ基金项目 国家自然科学基金资助项目（No.81503160）；江苏省 0.05），but there was no signifi -cant difference with albumin 卫生健康发展研究中心 2021年度开放课题（No.JSHD2021004）；江苏 （P＞0.05）. In blank plasma ，the protein binding rates of imatinib（4 000 ng/mL）at high concentration and its metabolites（2 000 ng/mL）were significantly lower than those of low （120， 60 ng/mL） and medium （750， 375 ng/mL）concentration （P＜0.01）. Average protein binding rates of imatinib and its metabolite in plasma of GIST patients were （99.0±0.3）% and（99.2±0.3）%，respectively；the correlation coefficients between the concentrations of imatinib and its metabolites and the protein binding rates were －0.298 5 and －3.332 3，respectively（all P＜0.05）. CONCLUSIONS The method for determining the plasma protein binding rates of imatinib and its metabolites is successfully established . The plasma protein binding rates of imatinib and its metabolites in patients with GIST are negatively correlated with drug concentration .

Simultaneous determination of acetaminophen and oxycodone in human plasma by LC–MS/MS and its application to a pharmacokinetic study / 药物分析学报

A simple and rapid liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was de-veloped and validated for simultaneous determination of acetaminophen and oxycodone in human plasma. Acetaminophen-d4 and oxycodone-d3 were used as internal standards. The challenge en-countered in the method development that the high plasma concentration level of acetaminophen made the MS response saturated while the desired lower limit of quantification (LLOQ) for oxycodone was hard to reach was well solved. The analytes were extracted by protein precipitation using acetonitrile. The matrix effect of the analytes was avoided by chromatographic separation using a hydrophilic C18 column coupled with gradient elution. Multiple reaction monitoring in positive ion mode was performed on tandem mass spectrometer employing electrospray ion source. The calibration curves were linear over the concentration ranges of 40.0–8000 ng/mL and 0.200–40.0 ng/mL for acetaminophen and oxycodone, respectively. This method, which could contribute to high throughput analysis and better clinical drug monitoring, was successfully applied to a pharmacokinetic study in healthy Chinese volunteers.

Construction of Recombinant Adenovirus Vector Expressing Mouse SPINK5 Gene and Its Curative Effect on Skin Lesions in Atopic Dermatitis Mice / 中国医科大学学报

Objective To construct a recombinant adenovirus vector expressing mouse SPINK5 gene,and observe its curative effect on the skin lesions in atopic dermatitis mice model. Methods By recombining DNA technology,the sequence of mouse SPINK5 gene was cloned into adeno?virus shuttle plasmid. Then it was transformed into HEK 293 cells with the adenoviral backbone plasmid to obtain the recombinant adenovirus. A mouse model of atopic dermatitis was established by system and local sensitization of Balb/c mice with ovalbumin . The effect of recombinant adeno?virus on the lesions of atopic dermatitis mice model was observed. Results The SPINK5 over?expressing adenovirus vector and atopic dermatitis mice model were successfully constructed. After 2 weeks of adenovirus?mediated SPINK5 gene intracutaneous injection,the redness and edema of lesions of AD model mice were obvious relieved. The pathological detection indicated that epidermal thickness and prickle cell layer ,inflammatory cell infiltration significant decreased accompanied with the model blank control. Conclusion The adenovirus?mediated SPINK5 gene had signifi?cant therapeutic effect to the atopic dermatitis mice model ,which provided a laboratory basis of application of SPINK5 gene product to therapy atopic dermatitis.

A Chinese multi-center study on the significance of monitoring imatinib plasma concentration in patients with gastrointestinal stromal tumor before and after administration / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the factors which may influence the imatinib plasma concentration in Chinese patients with gastrointestinal stromal tumor(GIST), and to illuminate the significance of monitoring imatinib plasma concentration in adjuvant therapy for patients with GIST.</p><p><b>METHODS</b>A cross-sectional study with 60 GIST patients who accepted the imatinib therapy after surgery was conducted. They were respectively administrated in 10 domestic hospitals from December 2014 to April 2016, including The First Affiliated Hospital of Nanjing Medical University(n=28), The Affiliated Hospital of Nantong University(n=9), The Affiliated Hospital of Xuzhou Medical College(n=6), Nanjing Drum Tower Hospital(n=5), The Second Affiliated Hospital of Nanjing Medical University (n=2), Jingling Hospital (n=2), The Second People's Hospital of Lianyungang(n=2), Shandong Provincial Hospital(n=2), Jiangsu Province Tumor Hospital(n=2), and The First Affiliated Hospital of Zhejiang University(n=2). Some specific time points for collecting blood sample before and after taking imatinib were determined, then liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was used for monitoring imatinib plasma concentration in patients with GIST. Linear regression analysis was used for the correlation analysis of imatinib plasma concentration with dosage, clinicopathologic feature and side effect.</p><p><b>RESULTS</b>Patients who could not tolerate 400 mg imatinib per day(n=3) received 300 mg per day. There was no significant difference in imatinib plasma concentration between patients with 300 mg and those with 400 mg imatinib(n=53)(P=0.527). However, the imatinib plasma concentration in patients with 600 mg imatinib per day (n=4) was significantly higher as compared to those with 400 mg(P=0.000). Linear regression analysis indicated a negative correlation between the imatinib plasma concentration in patients with 400mg imatinib per day for 90 days continuously and body surface area(R=0.074, P=0.035), but no significant correlations of with age, creatinine clearance and serum albumin concentration were observed (all P>0.05). The differences in imatinib plasma concentration were not statistically significant between patients of different gender and those taking proton-pump inhibitor (PPI) or not (both P>0.05). Difference in imatinib plasma concentration between patients with different surgery was significant (P=0.026). Compared to patients who underwent wedge resection, enterectomy and other surgeries, the imatinib plasma concentration of patients with subtotal gastrectomy or total gastrectomy decreased significantly (all P<0.05). After 90 days of taking imatinib continuously, linear regression analysis revealed a negative correlation between imatinib plasma concentration in patients with 400 mg imatinib per day and white blood cell count (R=0.103, P=0.013), and a positive correlation with serum alanine aminotransferase (ALT) concentration (R=0.076, P=0.033).</p><p><b>CONCLUSIONS</b>The imatinib plasma concentration in patients with larger body surface area, subtotal gastrectomy or total gastrectomy may be lower. For these patients, dosage of imatinib should be considered to increase in order to achieve effective plasma concentration. Excessive imatinib plasma concentration can result in some side effects, such as decrease of white blood cells and liver damage. Therefore, it is significant for receiving optimal clinical therapeutic efficacy to monitor imatinib plasma concentration, adjust imatinib dosage timely and keep imatinib plasma concentration in effective and safe range.</p>

Identification of mutation in the ?-L-iduronidase gene (IDUA) in Hurler syndromes in Chinese populations / 中国病理生理杂志

AIM: To investigate the mutation type in the IDUA gene of Liaoning district mucopolysaccharidosis I (MPS-I) patients. METHODS: The mutation type and polymorphism site in the IDUA gene of Liaoning district MPS-I patients were detected by PCR-RFLP, SSCP and DNA sequencing. RESULTS: ① There is a new mutation (1278-g-a) in the IDUA gene of Liaoning district MPS-I patients. ② There is no the common mutation (W402X and Q70X) of European patients and the common mutation (R89Q) of Japanese patients in the 10 families we studied. CONCLUSION: The mutation type in the IDUA gene of Liaoning district MPS-I patients is different from that of other countries and districts.

The mutation of ?-L-iduronidase gene for mucopolysaccharidosis type I in Liaoning district populations / 中国病理生理杂志

AIM: To investigate the mutatation type and polymorphism site in the ?-L-iduronidase (IDUA) gene of Liaoning district MPS-I patients. METHODS: The mutation type and polymorphism site in the IDUA gene of Liaoning district mucopolysaccharidosis type I (MPS-I) patients were detected by PCR-SSCP and DNA sequencing. RESULTS: ① 2 new mutations: R363H, 880+g-c in the IDUA gene of Liaoning district MPS-I patients were found. ② There were 3 polymorphism sites: R105Q、L118 and A361T in the IDUA gene of Liaoning district MPS-I patients. CONCLUSIONS: The mutation type in the IDUA gene of Liaoning district MPS-I patients is different from that of other countries and districts, while the polymorphism site in the IDUA gene of Liaoning district MPS-I patients is the same as that of other countries. [