A novel fluoropolymer as a protein delivery vector with robust adjuvant effect for cancer immunotherapy.

The inefficient treatment using protein-based nanovaccines is largely attributed to their inadequate immunogenicity. Herein, we developed a novel fluoropolymer (PF) via ring-opening polymerization and constructed a fluoropolymer-based nanovaccine for tumor immunotherapy. Due to the existence of fluoroalkyl chains, PF not only played a crucial role in tumor antigen delivery but also exhibited a remarkable adjuvant effect in enhancing the immunogenicity of nanovaccines. The nanovaccines formed by mixing PF with a model antigen ovalbumin (OVA) enhanced the uptake of antigen proteins by dendritic cells (DCs) and promoted the maturation and antigen presentation of DCs. Compared with free OVA, PF/OVA showed better efficacy in both pre-cancer prevention and tumor treatment. Furthermore, the proportion of CD4+ T and CD8+ T cells was significantly increased in lymph nodes and tumors of mice immunized with PF/OVA. Additionally, there was a great enhancement in the levels of key anti-tumor cytokines (TNF-α and IFN-γ) in the serum of the PF/OVA immunized mice. Our research has shown that fluoropolymer PF applied as a protein vector and adjuvant has great potential for the development of nanovaccines with robust immunogenicity.

[Relationship between atherogenic index of plasma and childhood asthma]. / è¡€æµ†è‡´åŠ¨è„‰ç¡¬åŒ–æŒ‡æ•°ä¸Žå„¿ç«¥æ”¯æ°”ç®¡å“®å–˜çš„ç›¸å ³æ€§åˆ†æž.

OBJECTIVES: To explore the relationship between atherogenic index of plasma (AIP) and childhood asthma. METHODS: This retrospective study included 86 children with asthma admitted to the Changzhou Second People's Hospital Affiliated to Nanjing Medical University from July 2020 to August 2022 as the asthma group and 149 healthy children undergoing physical examination during the same period as the control group. Metabolic parameters including total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and blood glucose, as well as general information of the children such as height, weight, body mass index, presence of specific dermatitis, history of inhalant allergen hypersensitivity, family history of asthma, and feeding history, were collected. Multivariable logistic regression analysis was used to study the relationship between AIP, triglycerides, and high-density lipoprotein cholesterol and asthma. The value of AIP, triglycerides, and high-density lipoprotein cholesterol for predicting asthma was assessed using receiver operating characteristic (ROC) curve analysis. RESULTS: The AIP and triglyceride levels in the asthma group were significantly higher than those in the control group, while high-density lipoprotein cholesterol was significantly lower (P<0.05). However, there was no significant difference in total cholesterol and low-density lipoprotein cholesterol between the two groups (P>0.05). Before and after adjusting for height, weight, presence of specific dermatitis, history of inhalant allergen hypersensitivity, family history of asthma, feeding method, and blood glucose, multivariable logistic regression analysis showed that AIP, triglycerides, and high-density lipoprotein cholesterol were associated with asthma (P<0.05). ROC curve analysis showed that the optimal cutoff value for predicting asthma with AIP was -0.333, with a sensitivity of 80.2%, specificity of 55.0%, positive predictive value of 50.71%, and negative predictive value of 82.85%. The area under the curve (AUC) for AIP in predicting asthma was significantly higher than that for triglycerides (P=0.009), but there was no significant difference in AUC between AIP and high-density lipoprotein cholesterol (P=0.686). CONCLUSIONS: AIP, triglycerides, and high-density lipoprotein cholesterol are all associated with asthma. AIP has a higher value for predicting asthma than triglycerides and comparable value to high-density lipoprotein cholesterol.

Protective effects of tanshinone â against cisplatin-induced nephrotoxicity in mice.

Objectives: Cisplatin (CDDP) is a highly effective chemotherapeutic agent, but its clinical application has been limited by nephrotoxicity. Tanshinone Ⅰ (T-I), a phenanthrenequinone compound extracted from the Chinese herb Danshen, has been used to improve circulation and treat cardiovascular diseases. The aim of this study was to investigate the protective effect of T-I on CDDP-induced nephrotoxicity in mice. Materials and Methods: The BALB/c mouse models of nephrotoxicity were established by a single intraperitoneal injection of 20 mg/kg CDDP on the first day of the experiment. Three hours prior to CDDP administration, the mice were dosed with 10 mg/kg and 30 mg/kg T-I for 3 consecutive days intraperitoneally to explore nephroprotection of T-I. Results: Treatment with T-I significantly reduced blood urea nitrogen and creatinine levels in serum observed in CDDP-administered mice, especially at a dose of 30 mg/kg. T-I at 30 mg/kg significantly decreased malondialdehyde levels and increased glutathione levels and the enzymatic activity of catalase in kidney tissue compared to CDDP. Additionally, T-I (30 mg/kg) significantly reversed the CDDP-decreased expression level of superoxide dismutase 2 protein in renal tissue. Histopathological evaluation of the kidneys further confirmed the protective effect of T-I. Conclusion: The findings of this study demonstrate that T-I can protect against CDDP-induced nephrotoxicity through suppression of oxidative stress.

Ras inhibitor farnesylthiosalicylic acid conjugated with IR783 dye exhibits improved tumor-targeting and altered anti-breast cancer mechanisms in mice.

Ras has long been viewed as a promising target for cancer therapy. Farnesylthiosalicylic acid (FTS), as the only Ras inhibitor has ever entered phase II clinical trials, has yielded disappointing results due to its strong hydrophobicity, poor tumor-targeting capacity, and low therapeutic efficiency. Thus, enhancing hydrophilicity and tumor-targeting capacity of FTS for improving its therapeutic efficacy is of great significance. In this study we conjugated FTS with a cancer-targeting small molecule dye IR783 and characterized the anticancer properties of the conjugate FTS-IR783. We showed that IR783 conjugation greatly improved the hydrophilicity, tumor-targeting and therapeutic potential of FTS. After a single oral administration in Balb/c mice, the relative bioavailability of FTS-IR783 was increased by 90.7% compared with FTS. We demonstrated that organic anion transporting polypeptide (OATP) and endocytosis synergistically drove the uptake of the FTS-IR783 conjugate in breast cancer MDA-MB-231 cells, resulting in superior tumor-targeting ability of the conjugate both in vitro and in vivo. We further revealed that FTS-IR783 conjugate could bind with and directly activate AMPK rather than affecting Ras, and subsequently regulate the TSC2/mTOR signaling pathway, thus achieving 2-10-fold increased anti-cancer therapeutic efficacy against 6 human breast cancer cell lines compared to FTS both in vivo and in vitro. Overall, our data highlights a promising approach for the modification of the anti-tumor drug FTS using IR783 and makes it possible to return FTS back to the clinic with a better efficacy.

[Analysis of epidemiological and clinical features of adenovirus infection in 80 children with acute respiratory tract infection].

By analyzing the epidemiological and clinical features of adenovirus in children with acute respiratory tract infection (ARTI), we provide a theoretical basis for early clinical diagnosis and treatment. Nasopharyngeal secretions were collected from 3480 children with ARTI, who were hospitalized at the No. 2 Hospital of Changzhou from January 2011 to December 2012. Adenovirus were detected using direct immunofluorescence assays. A total of 80 samples were positive for adenovirus (2.30%). The rate of adenovirus infection during 2011 was significantly higher than that in 2012, and the infection rate was higher in summer and autumn than in winter and spring. The infection rate was 1.14% among children aged < 1-year-old and the rates were higher among children in other age ranges. Adenovirus was found to be an important ARTI pathogen in children in Changzhou, mainly affecting children older than 1 year. ADV infections have various clinical presentations, but affected children tend to be severely ill with poor outcomes.

Synergism and rules of the new combination drug Yiqijiedu formulae (YQJD) on ischemic stroke based on amino acids (AAs) metabolism.

The use of combination drugs is considered to be a promising strategy to control complex diseases such as ischemic stroke. The detection of metabolites has been used as a versatile tool to reveal the potential mechanism of diverse diseases. In this study, the levels of 12 endogenous AAs were simultaneously determined quantitatively in the MCAO rat brain using RRLC-QQQ method. Seven AAs were chosen as the potential biomarkers, and using PLS-DA analysis, the effects of the new combination drug YQJD, which is composed of ginsenosides, berberine, and jasminoidin, on those 7 AAs were evaluated. Four AAs, glutamic acid, homocysteine, methionine, and tryptophan, which changed significantly in the YQJD-treated groups compared to the vehicle groups (P < 0.05), were identified and designated as the AAs to use to further explore the synergism of YQJD. The result of a PCA showed that the combination of these three drugs exhibits the strongest synergistic effect compared to other combination groups and that ginsenosides might play a pivotal role, especially when combined with jasminoidin. We successfully explored the synergetic mechanism of multi-component and provided a new method for evaluating the integrated effects of combination drugs in the treatment of complex diseases.

[Tanshinone IIA protects against triptolide-induced liver injury via Nrf2/ARE activation].

The aim of this study is to investigate the protection effect of tanshinone IIA (Tan) against triptolide (TP)-induced liver injury and the mechanisms involved. Acute liver injury was induced by intraperitoneal injection of TP (1 mg x kg(-1)) in mice. The activities of AST, ALT and LDH in serum and the levels of GSH, GST, GSH-PX, SOD, CAT and MDA in liver tissue were detected. The histopathological changes of liver tissues were observed after HE staining. Nrf2 translocation in liver tissue was detected by Western blotting, and real-time PCR was used to measure the expression levels of GCLC, NQO1 and HO-1 mRNA. The results showed that pretreatment with Tan significantly prevented the TP induced liver injury as indicated by reducing the activities of AST, ALT and LDH (P < 0.01). Tan pretreatment also prevented TP-induced oxidative stress in the mice liver by inhibiting MDA and restoring the levels of GSH, GST, SOD and CAT (P < 0.05). Parallel to these changes, pretreatment with Tan could attenuate histopathologic changes induced by TP. Furthermore, the results indicated that Tan pretreatment caused nuclear accumulation of Nrf2 as well as induction of mRNA expression of antioxidant response element (ARE)-driven genes such as GCLC, NQO1 and HO-1. These results indicated that Tan could protect against TP-induced acute liver injury via the activation of Nrf2/ARE pathway.

The G-quadruplex ligand, SYUIQ-FM05, targets proto-oncogene c-kit transcription and induces apoptosis in K562 cells.

CONTEXT: N'-(7-Fluoro-5-N-methyl-10H-indolo[3,2-b]quinolin-5-ium)-N,N-dimethylpropane-1,3-diamine iodide (SYUIQ-FM05) is a semi-synthetic derivative of cryptolepine which is from Cryptolepis sanguinolenta (Lindl.) Schlechter (Periplocaeae). This ligand inhibits telomerase activity by stabilizing the G-quadruplex structure and induces growth arrest in cancer cells. OBJECTIVE: The anticancer activity of SYUIQ-FM05 via inhibiting c-kit transcription was investigated in leukemic cells. MATERIALS AND METHODS: The cytotoxicity of SYUIQ-FM05 in K562 cells was evaluated using a cell viability assay and flow cytometry (FCM) at 0.4, 2.0, 10.0 and 20.0 nM. Under the same concentrations of SYUIQ-FM05 or 100 nM imatinib mesylate (IM), quantitative polymerase chain reaction (Q-PCR) investigated transcription of c-kit and bcl-2, and western blotting analyzed the expression levels of c-Kit, total mitogen-activated protein kinase kinases (MEKs), phospho-MEK (p-MEK), total extracellular regulated protein kinases (ERKs), phospho-ERK (p-ERK), Bcl-2 and Bax. RESULTS: SYUIQ-FM05 inhibited cellular growth with an IC(50) of 10.83 ± 0.05 nM in K562 cells. c-Kit transcription was suppressed 2.69-, 4.39-, 7.71- and 10.52-fold at 0.4, 2.0, 10.0 and 20.0 nM SYUIQ-FM05, respectively, which produced proportional loss of total c-Kit protein except IM. Both SYUIQ-FM05 and IM downregulated p-MEK and p-ERK. Furthermore, bcl-2 transcription was suppressed 1.58- and 1.86-fold at 10.0 and 20.0 nM SYUIQ-FM05, respectively, but 0.4 and 2.0 nM SYUIQ-FM05 had no effect. A decrease in Bcl-2 and an increase in Bax appeared in these treated cells. DISCUSSION AND CONCLUSION: These findings demonstrate that SYUIQ-FM05 could induce apoptosis in a leukemic cell line through inhibiting c-kit transcription, which supports the anticancer potency of SYUIQ-FM05 in c-Kit-positive leukemic cells.

[Schisandrin B protects against nephrotoxicity induced by cisplatin in HK-2 cells via Nrf2-ARE activation].

This study is to investigate the protection effect of schisandrin B (Sch B) against oxidation stress of HK-2 cells induced by cisplatin and the mechanisms involved. HK-2 cells were cultured and divided into different groups: solvent control group, cisplatin exposure group, positive group, Sch B treatment group. Cell viability and toxicity were evaluated by MTT and LDH assay. GSH level and SOD enzymes activities were also measured. DCFH-DA as fluorescence probe was used to detect ROS level by fluorescence microplate reader. Nrf2 translocation was detected by Western blotting. Real time Q-PCR was used to detect expressions of NQO1, HO-1 and GCLC mRNA level. The results showed that Sch B could significantly inhibit the decline of cell viability induced by cisplatin treatment (P < 0.05) and the protective effect was in a dose dependent manner. Furthermore, Sch B treatment significantly inhibited the increase of ROS level induced by cisplatin and reversed the decrease of GSH level (P < 0.05). When Sch B concentration was up to 5 micromol x L(-1), SOD enzyme activities were also enhanced significantly compared with that of the cisplatin group (P < 0.05). It was shown that Sch B could cause nuclear accumulation of Nrf2 in association with downstream activation of Nrf2 mediated oxidative response genes such as GCLC, NQO1 and HO-1. These results suggested Sch B could protect against the oxidative damage of HK-2 cells induced by cisplatin via the activation of Nrf2/ARE signal pathway.

Determination of HS270, a new histone deacetylase inhibitor, in rat plasma by LC-MS/MS--application to a preclinical pharmacokinetic study.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method has been developed and fully validated to determine HS270, a new histone deacetylase (HDAC) inhibitor, in rat plasma using SAHA as the internal standard (IS). After a single step liquid-liquid extraction with acetoacetate, analytes were subjected to LC-MS/MS analysis using positive electro-spray ionization (ESI(+)) under selected reaction monitoring mode (SRM). The chromatographic separation was achieved on a Hypurity C(18) column (50 mm × 2.1 mm, i.d., 5 µm). The MS/MS detection was conducted by monitoring the fragmentation of m/z 392.3→100.1 for HS270, m/z 265.1→232.1 for IS. The method had a chromatographic running time of 2.5 min and linear calibration curves over the concentrations of 0.5-1000 ng/mL. The recovery of the method was 70.8-82.5% and the lower limit of quantification (LLOQ) was 0.5 ng/mL. The intra- and inter-batch precisions were less than 15% for all quality control samples at concentrations of 1.0, 100.0, and 750.0 ng/mL. The validated LC-MS/MS method has successfully applied to a HS270 pharmacokinetic study after oral doses of 25, 50, 100, 200 mg/kg, and i.v. dose of 5 mg/kg to rats.

Development and validation of a highly rapid and sensitive LC-MS/MS method for determination of SZ-685C, an investigational marine anticancer agent, in rat plasma--application to a pharmacokinetic study in rats.

A sensitive and rapid method was developed and validated for the quantitative analysis of the novel anticancer agent SZ-685C in rat plasma using high-performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) in negative ion mode in order to support the following pre-clinical and clinical studies. SZ-685C and the internal standard (IS, emodin) were extracted from rat plasma by a simple liquid-liquid extraction technique using ethyl acetate as extraction solvent. Chromatographic separation was performed on an Elite Hypersil BDS C18 column (100 mm × 2.1 mm i.d., 3 µm). Elution was carried out using methanol/acetonitrile/2mM ammonium formate (pH 4) (80:15:5 (v/v/v)) at a flow-rate of 0.3 mL/min with a run time of 2.5 min. This assay was linear over a concentration range of 50-10,000 ng/mL with a lower limit of quantification of 50 ng/mL. The intra- and inter-batch precision was less than 15% for all quality control samples at concentrations of 100, 1000 and 7500 ng/mL. These results indicate that the method was efficient with a short run time and acceptable accuracy, precision and sensitivity. This method was successfully applied to explore pharmacokinetics of SZ-685C in rats after oral and intravenous administration of this agent. The absolute bioavailability is about 54.8-66.8% and the t(1/2) is 5.7-9.2h, these results provide basic information for further comprehensive pre-clinical research.

CYP4F2 rs2108622: a minor significant genetic factor of warfarin dose in Han Chinese patients with mechanical heart valve replacement.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * Genetic polymorphisms of VKORC1 and CYP2C9 are known to influence warfarin dosage. * Recent studies among Caucasians showed that polymorphisms of CYP4F2 also play a role in warfarin pharmacogenetics. * The contribution of CYP4F2 variants to the variability inwarfarin dose requirement in Chinese subjects remains to be investigated. WHAT THIS STUDY ADDS * This research was to study the effect of CYP4F2 variants on warfarin requirements in the Han Chinese population. * This study developed a multiple regression model including CYP2C9, VKORC1 3673G>A, CYP4F2 genotypes and age, weight, combination use of amiodarone which could explain 56.1% of the individual variability in warfarin dose CYP4F2 could explain 4% of the variance in warfarin dose. * We found that one novel genotypic polymorphism 5417G>T for Asp36Tyr, which was identified as an important marker of warfarin resistance, was absent in the Han Chinese population in our study. AIMS The objective of this study was to assess the effect of the CYP4F2 on the daily stable warfarin dose requirement in Han Chinese patients with mechanical heart valve replacement (MHVR). METHODS From March 2007 to November 2008, 222 Han Chinese MHVR patients were recruited in our study. VKORC1 3673G>A, 5417G>T, CYP2C9*3 and CYP4F2 rs2108622 were genotyped by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Polymorphisms of VKORC1 9041G>A were detected by direct sequencing. Multiple linear regression analysis was used to investigate the contribution of CYP4F2. RESULTS The CYP4F2 rs2108622 CT/TT group took a significantly higher stable warfarin dose (3.2 mg day(-1)) than the CC group (2.9 mg day(-1), 95% CI 0.2, 1.0, P= 0.033). The multiple linear regression model included VKORC1 3673G>A, CYP2C9, CYP4F2 genotypes and clinical characteristics. The model could explain 56.1% of the variance in stable warfarin dose in Han Chinese patients with MHVR. CYP4F2 contributed about 4% to the variance in the warfarin dose. There was no variation in the SNPs of VKORC1 5417G>T. CONCLUSION CYP4F2 is a minor significant factor of individual variability in the stable warfarin dose in Han Chinese patients with MHVR. The effect of CYP2C9 and VKORC1 genotypes on variability in the stable warfarin dose had also been confirmed.

[Association of INF-gamma/A+874T gene polymorphisms with respiratory syncytial virus bronchiolitis].

OBJECTIVE: A deficient interferon-gamma (IFN-gamma) response has been involved in the pathogenesis of severe respiratory syncytial virus (RSV) infection. Gene polymorphisms in IFN-gamma/A+874T have been associated with the susceptibility to asthma and might be related to disease severity of RSV infection. This study investigated the single nucleotide polymorphisms (SNPs) of IFN-gamma/A+874T in Han children in Wenzhou area and to explore the correlation between gene polymorphisms of IFN-gamma/A+874T and the susceptibility and disease severity of RSV bronchiolitis, as well as the effect of SNPs upon nasopharyngeal secretions (NPS) IFN-gamma and total serum IgE levels. METHODS: One hundred and fourteen hospitalized children with RSV bronchiolitis and 90 healthy controls were recruited. Sequence analysis was used for detecting the SNPs of IFN-gamma/A+874T. NPS IFN-gamma levels were measured using ELISA. Total serum IgE levels were assayed using the chemiluminescence method. RESULTS: IFN-gamma/A+874T gene polymorphisms were present in both the patient and the control groups. AA and AT genotypes were found in both groups, with a AA frequency of 82.5% vs 77.8% and a AT frequency of 17.5% vs 21.1% (p>0.05). The frequency of allele was 90.4% (A) and 9.6% (T) in the patient group, and 88.3% (A) and 11.7% (T) in the control group, respectively. There were no significant differences in the allele frequency between the two groups. Moreover, no difference was found both in NPS IFN-gamma and total serum IgE levels between AA and AT genotypes in the patient group. There were no significant differences in the variation of IFN-gamma/+874 between mild and moderate to severe cases. CONCLUSIONS: IFN-gamma/A+874T gene polymorphisms were present in Han children in Wenzhou area. Gene variations were not associated with the susceptibility and disease severity of RSV bronchiolitis as well as IFN-gamma and total serum IgE levels.

Simultaneous determination of mifepristone and monodemethyl-mifepristone in human plasma by liquid chromatography-tandem mass spectrometry method using levonorgestrel as an internal standard: application to a pharmacokinetic study.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously determine mifepristone and monodemethyl-mifepristone in human plasma using levonorgestrel as the internal standard (IS). After solid-phase extraction of the plasma samples, mifepristone, monodemethyl-mifepristone and the IS were subjected to LC-MS/MS analysis using electro-spray ionization (ESI) in the multiple reaction monitoring (MRM) mode. Chromatographic separation was performed on an XTERRA MS C(18) column (150 x 2.1 mm i.d., 5 microm). The method had a chromatographic run time of 4.5 min and linear calibration curves over the concentration ranges of 5-2000 ng/mL for mifepristone and monodemethyl-mifepristone. The recoveries of the method were found to be 94.5-103.7% for mifepristone and 70.7-77.3% for monodemethyl-mifepristone. The method had a lower limit of quantification (LLOQ) of 5.0 ng/mL and a lower limit of detection (LOD) of 1.0 ng/mL for both mifepristone and monodemethyl-mifepristone. The intra- and inter-batch precision was less than 15% for all quality control samples at concentrations of 10, 100 and 1000 ng/mL. These results indicate that the method was efficient with a short run time (4.5 min) and acceptable accuracy, precision and sensitivity. The validated LC-MS/MS method was successfully used in a pharmacokinetic study in healthy female volunteers after oral administration of 25 mg mifepristone tablet.

Archaeal diversity in acid mine drainage from Dabaoshan Mine, China.

Three acid mine drainage (AMD) samples collected from Dabaoshan Mine (Guangdong Province, China) were studied. In addition to physicochemical analyses, the diversity and community structures of the archaeal communities in these samples were described at the genetic level by amplified ribosomal DNA restriction analysis (ARDRA). Nine different ARDRA patterns were obtained from 146 clones and were studied as operational taxonomic units (OTUs), which were re-amplified and sequenced. Sequence data and phylogenetic analysis showed that most of the clones belonged to the Thermoplasmatales, and that archaea belonging to the Sulfolobales were absent. Only 1 OTU attributed to Ferroplasma was found and was observed to be abundant in all 3 samples. Eight OTUs were related to 2 new undefined groups in the Thermoplasmatales. Of the 8 OTUs, the clones in 2 similar units were isolated from samples collected from an abandoned sulfide mine (Huelva, Spain) and those in 5 similar units were isolated from samples collected from a closed copper mine (Tonglushan, China). These diversities were characterized by the reciprocal of Simpson's index (1/D) and correlated with the concentrations of ferrous ions and toxic ions in the AMD samples. The high temperature of the sampling sites was one of the factors that could explain why archaea belonging to the Thermoplasmatales were abundant in the analyzed AMD samples while those belonging to the Sulfolobales were absent.

Determination of levonorgestrel in human plasma by liquid chromatography-tandem mass spectrometry method: application to a bioequivalence study of two formulations in healthy volunteers.

A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to determine levonorgestrel in human plasma was developed and fully validated. After hexane-ethyl acetate (70:30, v/v) induced extraction from the plasma samples, levonorgestrel was subjected to LC/MS/MS analysis using electro-spray ionization. The MS system was operated in the selected reaction monitoring mode. Chromatographic separation was performed on a Hypersil BDS C18 column (i.d. 2.1x50 mm, particle size 3 microm). The method had a chromatographic running time of 2.0 min and linear calibration curves over the concentration ranges of 0.25-90 ng/mL for levonorgestrel. The lower limit of quantification of the method was 0.25 ng/mL for levonorgestrel. The intra- and inter-batch precision was 3.7-10.2 and 5.1-12.9%, respectively, for all quality control samples at concentrations of 0.5, 6.0 and 45.0 ng/mL. These results indicate that the method was efficient with a simple preparation procedure and a very short running time (2.0 min) for levonorgestrel compared with those methods reported in the literature and had high selectivity, acceptable accuracy, precision and sensitivity. The validated LC/MS/MS method was successfully used for a bioequivalence study of two tablet formulations of levonorgestrel in healthy volunteers.

Studies on quantitative analysis and automatic recognition of cell types of lung cancer.

Recognition of lung cancer cells is very important to the clinical diagnosis of lung cancer. In this paper we present a novel method to extract the structure characteristics of lung cancer cells and automatically recognize their types. Firstly soft mathematical morphology methods are used to enhance the grayscale image, to improve the definition of images, and to eliminate most of disturbance, noise and information of subordinate images, so the contour of target lung cancer cell and biological shape characteristic parameters can be extracted accurately. Then the minimum distance classifier is introduced to realize the automatic recognition of different types of lung cancer cells. A software system named "CANCER.LUNG" is established to demonstrate the efficiency of this method. The clinical experiments show that this method can accurately and objectively recognize the type of lung cancer cells, which can significantly improve the pathology research on the pathological changes of lung cancer and clinical assistant diagnoses.