Dietary Achievable Dose of Protocatechuic Acid, a Metabolite of Flavonoids, Inhibits High-Fat Diet-Induced Obesity in Mice

SCOPE

Protocatechuic acid (PCA), a gut microbiota metabolite of flavonoids, inhibits dietary obesity and increases uncoupling protein 1 (UCP1), a critical regulator responsible for adipose thermogenesis; however, these effects are achieved at dietary unachievable (pharmacological) dose. It evaluates whether dietary achievable dose of PCA inhibits adiposity by activating adipose thermogenesis.

METHODS AND RESULTS

Six-week-old male C57BL/6J mice are fed a high-fat diet (HFD) alone (control) or supplemented with 0.003% PCA w/w for 16 weeks. PCA consumption does not affect food intake but appreciably reduces body weight gain, improves insulin sensitivity, and attenuates hepatic steatosis. These effects are associated with no significant changes in the abundance of UCP1 in adipose tissues. Instead, PCA consumption increases the abundance and enzymatic activity of carnitine palmitoyltransferase 1 (the first rate-limiting enzyme in fatty acid oxidation) in the livers, inguinal white, and brown adipose tissues. Surprisingly, PCA at physiologically achievable dose does not affect the abundance and enzymatic activity of carnitine acyltransferase-1 expression and the capacity of fatty acid oxidation in 3T3-L1-derived white or brown adipocytes and human hepatoma HepG2 cells.

CONCLUSIONS

Dietary achievable dose of PCA attenuates HFD-induced adiposity, which is likely achieved by increasing fatty acid oxidation other than activating adipose thermogenesis.

Protocatechuic acid boosts continual efferocytosis in macrophages by derepressing KLF4 to transcriptionally activate MerTK

Macrophages clear apoptotic cells through a process called continual efferocytosis. We found that protocatechuic acid (PCA), a polyphenolic compound abundant in fruits and vegetables, increased the continual efferocytic capacity of macrophages and inhibited the progression of advanced atherosclerosis. PCA reduced the intracellular amounts of microRNA-10b (miR-10b) by promoting its secretion in extracellular vesicles, which led to an increase in the abundance of the miR-10b target Krüppel-like factor 4 (KLF4). In turn, KLF4 transcriptionally induced the gene encoding Mer proto-oncogene tyrosine kinase (MerTK), an efferocytic receptor for the recognition of apoptotic cells, resulting in increased continual efferocytic capacity. However, in naive macrophages, the PCA-induced secretion of miR-10b did not affect KLF4 and MerTK protein abundance or efferocytic capacity. In mice, oral administration of PCA increased continual efferocytosis in macrophages residing in the peritoneal cavities, thymi, and advanced atherosclerotic plaques through the miR-10b-KLF4-MerTK pathway. In addition, pharmacological inhibition of miR-10b with antagomiR-10b also increased the efferocytic capacity of efferocytic but not naive macrophages in vitro and in vivo. Together, these data describe a pathway that promotes continual efferocytosis in macrophages through miR-10b secretion and a KLF4-dependent increase in MerTK abundance, which can be activated by dietary PCA and which has implications for understanding the regulation of continual efferocytosis in macrophages.

Re-Visiting Antioxidant Therapy in Murine Advanced Atherosclerosis with Brussels Chicory, a Typical Vegetable in Mediterranean Diets

Brussels chicory, a typical vegetable in Mediterranean diets, has been recently reported to stabilize advanced atherosclerotic plaques in the brachiocephalic artery of apoE-deficient (Apoe-/-) mice. Herein, we investigated whether Brussels chicory can stabilize advanced plaques in the aorta via improving oxidative stress. Thirty week old Apoe-/- mice were fed the AIN-93G diet or supplemented with 0.5% freeze-dried Brussels chicory for twenty weeks. Aortic plaque size and stability, aortic relaxation, monocyte adhesion to aortic endothelium, free radicals, and enzymatic and non-enzymatic factors involved in free radical production and elimination in aorta and serum were measured. Brussels chicory consumption did not alter aortic plaque size, however, it stabilized aortic plaques, promoted aortic relaxation, and also inhibited monocyte adhesion to aortic endothelium. Moreover, this administration reduced oxidized LDL (ox-LDL) and 4-hydroxynonenal (4-HNE) content in aortic plaques, associated with inhibited aortic NADPH oxidase (NOX) and uncoupled endothelial nitric oxide synthase (eNOS)-mediated free radical production. However, Brussels chicory consumption did not appreciably alter aortic and serum superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities, aortic glutathione (GSH), as well as serum non-enzymatic antioxidants, such as bilirubin, uric acid, and GSH. Collectively, improved oxidative stress might contribute to the atheroprotective effect of Brussels chicory, supporting the prospect of the antioxidant therapy in advanced atherosclerosis progression.

[Expression of miR-17-5p in the plasma of patients with multiple myeloma and its role in tumorigenesis and development]

Objective: To investigate the expression of miR-17-5p in the plasma of patients with multiple myeloma (MM) and its role in tumorigenesis and development. Methods: Patients diagnosed with unidentified monoclonal gammopathy of undetermined significance (MGUS) or MM in Cancer Hospital of Zhengzhou University from April 2013 to April 2018 were enrolled, as well as 20 healthy volunteers. Reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression levels of miR-17-5p in plasma circulation and bone marrow mononuclear cells. There were 22 cases with newly diagnosed MM (NDMM), 11 cases with complete remission MM (CRMM) and 59 case with recurrent refractory MM (RRMM). The expression levels of miR-17-5p in each group were analyzed. The correlation analysis was used to evaluate the relationship between plasma miR-17-5p and the proportion of serum M protein and bone marrow plasma cells in patients with untreated multiple myeloma. Receiver operating characteristic (ROC) curve was used to evaluate the possibility of plasma miR-17-5p as a molecular marker related to MM diagnosis. After over expression or knockdown of miR-17-5p expression, CCK-8 method was used to detect the effect of miR-17-5p on the proliferation of MM cell line. The effect of miR-17-5p on the proliferation of MM cells was detected in nude mice subcutaneous tumorigenesis experiment. Results: The expression of miR-17-5p in bone marrow mononuclear cells in NDMM and RRMM group were higher than those in healthy volunteers [1.37 (0.47, 4.87), 2.68 (1.02, 5.02) vs 1.00 (1.00, 1.00), all P<0.05], and the expression levels of miR-17-5p in plasma were also higher than those in healthy control group [1.85 (0.92, 3.51), 2.79 (1.22, 5.04) vs 1.00 (1.00, 1.00), all P<0.05]. The expression of miR-17-5p in MM cell lines such as KMS-11, RPMI-8226, H929, MM-1R, U266B1 were higher than that in bone marrow mononuclear cells of healthy control group (3.96±0.68, 1.58±0.32, 3.51±0.55, 5.08±0.76, 3.22±0.75 vs 1.00±0, all P<0.05) ; Plasma miR-17-5p was positively correlated with the ratio of serum M protein and bone marrow plasma cells (r=0.50, P<0.05; r=0.60, P<0.01). ROC curve showed that the specificity was 0.591 and the sensitivity was 0.900 of plasma miR-17-5p as a molecular marker related to diagnosis (area under ROC curve=0.74, cut-off value: 0.491). CCK-8 results showed that over expression of miR-17-5p increased the proliferation of RPMI-8226 and NCI-H929 cell lines at 72 hours compared with the control group (1.37±0.11 vs 1.07±0.09, 2.14±0.09 vs 1.82±0.11, both P<0.05), and low expression of miR-17-5p reduced the proliferation of NCI-H929 and MM-1R cell lines at 72 hours compared with the control group (1.38±0.09 vs 1.83±0.11, 1.45±0.10 vs 1.73±0.09, both P<0.05). The subcutaneous tumorigenesis experiment in nude mice showed that the tumor volume of miR-17-5p over expression group was larger than that of the control group [(1 865±181) vs (1 389±227) mm3, P<0.05], and the tumor volume of miR-17-5p low expression group was smaller than that of the control group [ (1 006±171) vs (1 389±227) mm3, P<0.05]. Conclusion: miR-17-5p may play an oncogene role in MM cell lines as a plasma molecular marker related to the development of MM disease.

[Clinical study of mesenchymal stem cells from third-party donors in the treatment of refractory late onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplanation]

Objective: To examine the efficacy and safety of third-party bone marrow-derived mesenchymal stem cells (MSCs) in the treatment of refractory delayed hemorrhagic cystitis (LOHC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Twenty patients with refractory LOHC received conventional therapy combined with MSCs obtained from third-party donors' bone marrow (BM) . MSCs were given intravenously at a dose of 1 × 10(6) cells/kg once weekly until either the symptoms improved or no changes in LOHC were seen after continuous infusion four times. BK viruria (BKV) -DNA, JC viruria (JCV) -DNA, and CMV-DNA were detected by real-time quantitative PCR before and 8 weeks after the MSCs infusion. Results: ① Of the 20 patients with refractory LOHC, 15 were males, and 5 were females, and the median age was 35 (15-56) years. There were 5 cases of acute lymphoblastic leukemia (ALL) , 9 cases of acute myeloid leukemia (AML) , 5 cases of myelodysplastic syndrome (MDS) , and 1 case of maternal plasma cell like dendritic cell tumor (BPDCN) . There were 4 cases of HLA identical transplantation and 16 cases of HLA incomplete transplantation. ②The median number of MSC infusions for each patient was 3 (range: 2-8) . Seventeen patients achieved complete response, and one had a partial response after treatment. The overall response rate was 90%. Over a median follow-up period of 397.5 days (range 39-937 days) post-transplantations, 13 patients survived, and 7 died. The causes of death included aGVHD (1 case) , infections (5 cases) , and TMA (1 case) . ③The copy numbers of BKV-DNA and CMV-DNA in urine in the 8th week after MSCs infusion were significantly lower than those observed before treatment (11342.1×10(8) copies/L vs 5.2×10(8) copies/L, P=0.016; 3170.0×10(4) copies/L vs 0.2×10(4) copies/L, P=0.006, respectively) , while JCV-DNA did not significantly differ when compared to before treatment (P=0.106) . ④ No adverse reactions related to MSC infusion occurred in any of the 20 patients. Conclusion: Third-party bone marrow-derived MSC has significant efficacy and good safety in the treatment of refractory LOHC after allogeneic HSCT.

Terpene Lactucopicrin Limits Macrophage Foam Cell Formation by a Reduction of Lectin-Like Oxidized Low-Density Lipoprotein Receptor-1 in Lipid Rafts

SCOPE

Sustained inflammation promotes macrophage foam cell formation by promoting cholesterol influx and impairing cholesterol efflux. Terpene lactucopicrin, affluent in vegetables of the Asteraceae family (e.g., chicory, curly escarole, and lettuce) can inhibit atherogenesis in mice. However, it remains unknown whether and how lactucopicrin regulates macrophage foam cell formation.

METHODS AND RESULTS

Lactucopicrin at physiologically reachable concentrations inhibits oxidized low-density lipoprotein (oxLDL)-induced foam cell formation in inflammatory mouse bone marrow derived macrophages established by 50 pg mL^-1 of LPS, reachable level in patients with metabolic endotoxemia. This effect is not due to modulation of cholesterol efflux, but reliant on a reduction in lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1)-mediated cholesterol influx. Mechanistically, lactucopicrin does not affect LOX-1 expression, cellular oxidative stress, and exocytosis, known mechanisms regulating LOX-1 function in cholesterol influx. Strikingly, lactucopicrin selectively decreases LOX-1 content in lipid rafts, an effect responsible for the lactucopicrin effect on cholesterol influx. Moreover, ApoE^-/- mice fed a high fat diet supplemented with lactucopicrin for 12 weeks display fewer macrophage foam cells within atherosclerotic plaques relative to the control mice.

CONCLUSION

Lactucopicrin limits macrophage foam cell formation through a reduction of LOX-1 distribution in lipid rafts, thus contributing to its atheroprotective effect.

[Metabolism of New Psychoactive Substances 4F-MDMB-BUTINACA in Zebrafish]

Abstract

Objective To study the metabolic transformation pathways of 4F-MDMB-BUTINACA in vivo by establishing zebrafish models. Methods Six adult zebrafish were randomly divided into blank control group and experimental group, with three fish in each group. After the zebrafish in the experimental group were exposed to 1 μg/mL 4F-MDMB-BUTINACA for 24 h, they were transferred to clean water and cleaned three times, then pretreated for instrumental analysis. The zebrafish in blank control group were not exposed to 4F-MDMB-BUTINACA. Mass spectrometry and structural analysis of 4F-MDMB-BUTINACA and its metabolites were conducted by liquid chromatography-high resolution mass spectrometry and Mass Frontier software. Results A total of twenty-six metabolites of 4F-MDMB-BUTINACA were identified in zebrafish, including eighteen phase Ⅰ metabolites and eight phase Ⅱ metabolites. The main metabolic pathways of phase Ⅰ metabolites of 4F-MDMB-BUTINACA in zebrafish were ester hydrolysis, N-dealkylation, oxidative defluorination and hydroxylation, while the main metabolic pathway of phase Ⅱ metabolites was glucuronidation. Conclusion Metabolite Md24 （ester hydrolysis） and Md25 （ester hydrolysis combined with dehydrogenation） would be recommended to be potentially good biomarkers for abuse of 4F-MDMB-BUTINACA.

[Research Advances in the Monitoring of New Psychoactive Substances in Municipal Wastewater]

Abstract

In recent years, as the third-generation of drugs, new psychoactive substances （NPS） have expanded rapidly and become a serious concern for China's anti-drug prevention and control system. As a new drug monitoring technology in the current anti-drug field, wastewater analysis is an objective, real-time, accurate, convenient and effective drug monitoring method. In recent years, it has gradually been applied to the monitoring of NPS. This study summarizes wastewater sample collection, target stability research, wastewater sample pretreatment, wastewater sample analysis methods, target NPS consumption calculations and actual monitoring applications, with a view to the construction of a monitoring system for NPS in wastewater, real-time and accurate grasp of information on the use of NPS in cities, the reflection of the actual consumption of different types of NPS and consumption trends in a short period of time, and prediction of the development trend of abused use, which is of great significance for combating NPS crimes, serving and guaranteeing the personal safety of the people, and maintaining social stability.

[Research Progress on Metabolite Identification of Synthetic Cannabinoid New Psychoactive Substances]

Abstract

Synthetic cannabinoids are currently a class of new psychoactive substances with the largest variety and most abused. Metabolite identification research can provide basic data for monitoring synthetic cannabinoids abuse, which is the current research hotspot. The main trend of structural modification of synthetic cannabinoid is to replace the fluorine atom on pentyl indole or indazole cyclopentyl with hydrogen atom, which greatly improves the biological activity of the compound. The main metabolic reactions include hydroxylation, fluoropentyl oxidative, ester hydrolyze, amide hydrolysis. Liquid chromatography-high resolution mass spectrometry has become the preferred choice for the structural identification of metabolites. This review mainly summarizes research on metabolism software prediction and human hepatocyte model, human liver microsomes model, rat in vivo model, zebrafish model and fungus C. elegans model in metabolite identification based on the structure and classification of synthetic cannabinoids.

[Analysis and Application of Seven Common New Psychoactive Substances of Synthetic Cannabinoids in Hair]

Objective To establish a detection method for common new psychoactive substances of synthetic cannabinoids in hair with ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods In the 1 mL of internal standard methanol solution, 20 mg hair was added. After cryogenic grinding and ultrasonic extraction, the extract was separated by ACQUITY UPLC HSS T₃ column （100 mm×2.1 mm, 1.8 μm）. The mobile phase A was aqueous solution that composed of 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. The mobile phase B was acetonitrile. Electrospray ionization source in positive ion mode was used for data acquisition in multi-reaction monitoring （MRM） mode. Results The seven common new psychoactive substances of synthetic cannabinoids in hair had a good linear relationship within their respective linear ranges （r>0.99）, the limits of detection were 0.5-2 pg/mg, the limits of quantification were 1-5 pg/mg, the intra-day and inter-day precisions were 0.1%-12.6%, the intra-day and inter-day accuracies were 89.2%-110.7%, the recovery rates were 52.3%-93.3%, and the matrix effects were 19.1%-95.2%. Conclusion The established method has a simple sample preparation process and high sensitivity. It is suitable for qualitative and quantitative analysis of common new psychoactive substances of synthetic cannabinoids in hair.

Identification of Cannabis Sativa L. Based on rbcL Sequence

Abstract

Objective To assess the feasibility of the rbcL sequence of chloroplast DNA as a genetic marker to identify Cannabis sativa L. Methods The rbcL sequences in 62 Cannabis sativa L. samples, 10 Humulus lupulus samples and 10 Humulus scandens DNA samples were detected, and 96 rbcL sequences of the Cannabaceae family were downloaded from Genbank. Sequence alignment was performed by MEGA X software, the intraspecific and interspecific Kimura-2-Parameter （K2P） genetic distances were calculated, and the system clustering tree was constructed. Results The rbcL sequence length acquired by sequencing of Cannabis sativa L. and Humulus scandens were 617 bp and 649 bp, respectively, and two haplotypes of Cannabis sativa L. were observed in the samples. The BLAST similarity search results showed that the highest similarity between the sequences acquired by sequencing and Cannabis sativa L. rbcL sequences available from Genbank was 100%. The genetic distance analysis showed that the maximum intraspecific genetic distance （0.004 9） of Cannabis sativa L. was less than the minimum interspecific genetic distance （0.012 9）. The results of median-joining network and system clustering tree analysis showed that Cannabis sativa L. and other members of the Cannabaceae family were located in different branches. Conclusion The rbcL sequence could be used as a DNA barcode for identifying Cannabis sativa L., and combined with comparative analysis of the rbcL sequence and system cluster analysis could be a reliable and effective detection method for Cannabis sativa L. identification in forensic investigation.

Analysis Methods of Common Herbicides in Biological Material and Research Progress

Abstract

Herbicides are a kind of chemical or biological agents that can effectively destroy or inhibit weed growth. Because of the widespread and frequent use of herbicides, herbicide poisonings have often been reported. At present, the main species reported to have caused poisoning are paraquat, diquat, glyphosate, and glufosinate. The main instrumental analysis method is LC-MS. This paper reviews the research progress on analysis methods of common herbicides in biological material and their application, summarizes the sample pretreatment and instrumental analysis situation of qualitative and quantitative analysis of herbicides in biological material, and collects test data of actual poisoning cases, to provide reference for clinical diagnosis and treatment and forensic identification of herbicide poisoning.

Mass Spectrometry Imaging and Its Application in Forensic Toxicology

Mass spectrometry imaging （MSI） is a new imaging technology that can simultaneously detect and record the spatial distribution information of multiple molecules on the sample surface without labeling. The main principle of MSI is to combine mass spectrometry with imaging technology and irradiate the sample slice with ion beam or laser to ionize the molecules on its surface, obtain the mass spectrometry signal through the detector, convert the obtained data into pixel points by the imaging software, and then construct the spatial distribution image of the target compound on the tissue surface. The sample preparation for MSI include： sample collection and storage, tissue section, tissue pretreatment, selection and application of matrix. At present, this technology has been widely used in the fields of biomedicine, new drug development and proteomics, and its application in the field of forensic toxicology has also gradually attracted attention. This article reviews the principles and sample preparation process of MSI, describes the application of MSI in abused substances and metabolites of various material matrices, herbal mixtures, latent fingerprints, hair and animal and plant tissues, and discusses the prospects of the application of this technology in forensic toxicology, in order to provide ideas and references for the application of MSI technology in forensic toxicology.

The dual role of anti-viral therapy in the treatment of Coronavirus disease 2019

OBJECTIVE

Coronavirus disease 2019 (COVID-19) has become a worldwide public health emergency; unfortunately, there is currently no treatment for improving outcomes or reducing viral-clearance times in infected patients. The aim of the present study was to evaluate the efficacy of interferon (IFN) with or without lopinavir and ritonavir as antiviral therapeutic option for treating COVID-19 infection.

PATIENTS AND METHODS

The present study enrolled 148 patients that received either standard care, treatment with IFN alfa-2b, or IFN alfa-2b combined with lopinavir plus ritonavir. Viral testing was performed using Reverse-Transcription Polymerase Chain Reaction (RT-PCR).

RESULTS

There was no significant difference in the viral-clearance time at 28 days after treatment between patients receiving standard care and those receiving anti-viral treatments. However, the average viral-clearance time of patients receiving standard care (14 days) was shorter than that for patients receiving IFN alfa-2b or IFN alfa-2b combined with lopinavir plus ritonavir (15.5 or 17.5 days) (p<0.05). Patients treated with IFN alfa-2b within five days or IFN alfa-2b combined with lopinavir plus ritonavir after three days of symptoms exhibited shorter viral-clearance times than the other groups (p<0.05). Moreover, viral-clearance times were significantly longer in patients receiving standard care or anti-viral treatment 5 days after symptoms appeared than those of patients who received these treatments within five days of symptom onset (p<0.05).

CONCLUSIONS

Early symptomatic treatment is most critical for maximizing amelioration of COVID-19 infection. Anti-viral treatment might have complicated effect on viral-clearance.

[Influence of Halogenated Hydroxyl-Alkanes Inhalation Anesthetic on the Determination of Ethanol Content in Blood]

Objective To study the influence of halogenated hydroxyl-alkanes inhalation anesthetic on the determination of ethanol content in blood. Methods Halogenated hydroxyl-alkanes were analyzed by headspace gas chromatography with double column confirmatory detection method. The influence of halogenated hydroxyl-alkanes on determination of ethanol content in blood sample by headspace gas chromatography was explored under the different detection conditions of KB-BAC1/ KB-BAC2 and J&W DB-ALC1/DB-ALC2 gas chromatographic column. Results The retention time of sevoflurane and enflurane was similar to that of ethanol and tert butanol respectively when using the J&W DB-ALC1/DB-ALC2 gas chromatographic column, and interfered with the detection of ethanol content in blood; only J&W DB-ALC1 gas chromatographic column can separate the sevoflurane and ethanol components, so as to eliminate their influence on the detection of ethanol content in blood. When using KB-BAC1/KB-BAC2 gas chromatographic column, the retention time of sevoflurane, isoflurane and ethanol is similar, especially that of sevoflurane and ethanol, and sevoflurane obviously interferes with the determination of ethanol content in blood. Conclusion Halogenated hydroxy-alkanes interfere with determination of ethanol content in blood by headspace gas chromatography. The interference can be discriminated effectively by choosing the suitable chromatographic column and double column confirmatory detection.

Establishment and Its Application of UPLC-MS/MS Method for 20 Fentanyl-related Substances in Blood

Objective To establish an ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） rapid determination method for simultaneous analysis of 20 fentanyl-related substances in blood. Methods With fentanyl-D₅ as an internal standard, the blood was extracted by liquid-liquid extraction （LLE）, then separated with an ACQUITY UPLC HSS T₃ chromatographic column, and finally 20 fentanyl-related substances were simultaneously analyzed with multiple reaction monitoring （MRM） mode. Results The limits of detection （LOD） of all compounds were 0.02-0.03 ng/mL, and the limits of quantitation （LOQ） were 0.05-0.2 ng/mL. Within the mass concentration range of 0.05-40 ng/mL, 20 fentanyl-related substances had a good linear relationship, and correlation coefficients were larger than 0.99. The accuracy of the method was 87.69%-114.68% and the extraction recovery rate was 85.35%-101.80%, and no significant matrix effect was observed. The established method was successfully applied to the detection of sufentanil in rat blood after sufentanil was injected. Sufentanil could still be detected in blood of rats 10 h after sufentanil injection. Conclusion The established method has the advantages of simple pretreatment, high sensitivity and good selectivity, and can be used for the determination of fentanyl-related substances in forensic toxicology analysis.

Rapid Determination of Cocaine and Its Metabolite Benzoylecgonine in Hair by LC-MS/MS

OBJECTIVES

To establish a rapid determination method with LC-MS/MS for cocaine and its metabolite benzoylecgonine in hair.

METHODS

Deuterated internal standards （cocaine-D₃ and benzoylecgonine-D₈） were added to the decontaminated hair. After the extraction by ultrasonication with methanol, the compounds were separated by the Restek Allure PFP propyl column, and cocaine and benzoylecgonine were simultaneously analysed in multiple reaction monitoring mode.

RESULTS

The cocaine and benzoylecgonine in hair showed a good linearity in the range of mass fraction between 0.02 and 10.00 ng/mg with the limits of detection of 0.01 ng/mg.

CONCLUSIONS

The developed method is simple and rapid with a good selectivity, which is suitable for the determination of cocaine and its metabolite benzoylecgonine in hair.

[Effect of comprehensive schistosomiasis control strategy with focus on cattle and sheep removal in Junshan District, Yueyang City]

Objective To evaluate the effect of comprehensive schistosomiasis control measures with focus on total removal of cattle and sheep in Junshan District, Yueyang City. Methods The retrospective review and field survey were implemented in the pilot villages in Junshan District. The data of Schistosoma japonicum infection status of human, cattle, sheep and Oncomelania hupensis snails, and density of snails were gathered and modeled in the period of 2006 to 2016. Results The prevalence of schistosome infection in residents in the pilot villages decreased from 3.44% in 2006 to 0.59% in 2012 (F = 14.501, P = 0.013). After removal of all the cattle and sheep in 2013, the prevalence of schistosome infection in the residents decreased to zero in 2016 (F = 14.148, P = 0.033). The density of living snails decreased from 0.883 3/0.1 m² in 2006 to 0.308 8/0.1 m² in 2012 (F = 76.250, P = 0.005). Conclusion The comprehensive schistosomiasis control strategy with focus on cattle and sheep removal is remarkably effective.

[Identification of New Designer Benzodiazepine Diclazepam in Drug Facilitated Sexual Assault]

OBJECTIVES

To identify the new designer drugs which are totally unknown and not in the routine testing list by the technologies such as high-resolution mass spectrometry in drug facilitated sexual assault, in order to solve the problem in actual cases.

METHODS

The milky fluid from an actual case was extracted and analyzed using LC-QE, ¹H-NMR and GC-MS, respectively. The accurate masses and cluster ions isotope patterns of unknown compound were obtained by LC-QE. The molecular formula was confirmed as C₁₆H₁₂C₂N₂O based on the protons number of ¹H-NMR. The isomers diclazepam and 4-chlorodiazepam were separated and detected with GC-MS.

RESULTS

The new designer benzodiazepine as diclazepam in the milky fluid was identified. The results provided direct evidence for the investigation and qualitative analysis of such cases.

CONCLUSIONS

The combined application of various methods, including LC-QE, ¹H-NMR and GC-MS, can be used to detect unknown new psychoactive substances.

[Identification of Methamphetamine Abuse and Selegiline Use： Chiral Analysis of Methamphetamine and Amphetamine in Urine]

OBJECTIVES

To study the content variation of selegiline and its metabolites in urine, and based on actual cases, to explore the feasibility for the identification of methamphetamine abuse and selegiline use by chiral analysis.

METHODS

The urine samples were tested by chiral separation and LC-MS/MS method using CHIROBIOTIC™ V2 chiral liquid chromatography column. The chiral analysis of methamphetamine and amphetamine were performed on the urine samples from volunteers of selegiline use and drug addicts whom suspected taking selegiline.

RESULTS

After 5 mg oral administration, the positive test time of selegiline in urine was less than 7 h. The mass concentrations of R（-）-methamphetamine and R（-）-amphetamine in urine peaked at 7 h which were 0.86 μg/mL and 0.18 μg/mL and couldn't be detected after 80 h and 168 h, respectively. The sources of methamphetamine and amphetamine in the urine from the drug addicts whom suspected taking selegiline were analysed successfully by present method.

CONCLUSIONS

The chiral analysis of methamphetamine and amphetamine, and the determination of selegiline's metabolites can be used to distinguish methamphetamine abuse from selegiline use.

[The Role of Segmental Analysis of Clonazepam in Hair in Drug Facilitated Cases]

OBJECTIVES

To infer the frequency of dosage and medication history investigate of the victims in drug facilitated cases by the segmental analysis of clonazepam in hair.

METHODS

Freezing milling under liquid nitrogen environment combined with ultrasonic bath was used as sample pretreatment in this study, and liquid chromatography-tandem mass spectrometry was used for the segmental analysis of the hair samples collected from 6 victims in different cases. The concentrations of clonazepam and 7-aminoclonazepam were detected in each hair section.

RESULTS

Clonazepam and its metabolite 7-aminoclonazepam were detected in parts of hair sections from the 6 victims. The occurrence time of drug peak concentration was consistent with the intake timing provided by victims.

CONCLUSIONS

Segmental analysis of hair can provide the information of frequency of dosage and intake timing, which shows an unique evidential value in drug facilitated crimes.

[Evaluation of Brodifacoum-induced Toxicity by Metabonomics Approach Based on HPLC-TOF-MS]

OBJECTIVES

To analyse the metabolic changes in urine of rats with brodifacoum intoxication, and to reveal the molecular mechanism of brodifacoum-induced toxicity on rats.

METHODS

By establishing a brodifacoum poisoning rats model, the urine metabolic profiling data of rats were acquired using high performance liquid chromatography-time of flight mass spectrometry （HPLC-TOF-MS）. The orthogonal partial least squares analysis-discrimination analysis （OPLS-DA） was applied for the multivariate statistics and the discovery of differential metabolites closely related to toxicity of brodifacoum.

RESULTS

OPLS-DA score plot showed that the urinary metabolic at different time points before and after drug administration had good similarity within time period and presented clustering phenomenon. Comparing the urine samples of rats before drug administration with which after drug administration, twenty-two metabolites related to brodifacoum-induced toxicity were selected.

CONCLUSIONS

The toxic effect of brodifacoum worked by disturbing the metabolic pathways in rats such as tricarboxylic cycle, glycolysis, sphingolipid metabolism and tryptophan metabolism, and the toxicity of brodifacoum is characterized of accumulation effect. The metabonomic method based on urine HPLC-TOF-MS can provide a novel insight into the study on molecular mechanism of brodifacoum-induced toxicity.

[Determination of Sulfide Ion in Blood from Hydrogen Sulfide Poisoning Cases]

OBJECTIVES

To establish a gas chromatography-mass spectrometry （GC-MS） method for the determination of sulfide ion in blood and apply it to the practical cases.

METHODS

The 1, 3, 5-tribromobenzene was selected as an internal standard, and 0.2 mL blood sample was collected and analyzed using GC-MS after α-Bromo-2, 3, 4, 5, 6-pentafluorobenzyl bromide derivatization.

RESULTS

The mass concentration of sulfide ion in blood had good linearity in the range of 0.2-40 μg/mL with a limit of detection （LOD） of 0.05 μg/mL. The mass concentration of sulfide ion was less than 0.05 μg/mL in blank blood from different sources such as healthy subjects and dead cases. In 3 sulfide poisoning cases, sulfide ion was detected in the blood samples of 6 victims, and the mass concentration range was 1.02-3.13 μg/mL.

CONCLUSIONS

This study establishes a method for investigation of sulfide ion in blood which has been applied successfully to the cases of fatal sulfide poisonings.

Efficacy and safety of basiliximab in liver transplantation for patients with hepatitis B virus-related diseases: a single centre study

AIMS

We aim to evaluate the efficacy and safety of basiliximab in liver transplantation (LT) for patients with hepatitis B virus-related diseases.

METHODS

A total of 268 patients with hepatitis B virus-related diseases undergoing LT were enrolled and divided into two groups according to the usage of basiliximab. Total survival, the survival of high-risk patients defined by the posttransplant model for predicting mortality, acute rejection rate, biochemical parameters and other follow-up data were compared between the two groups.

RESULTS

Group Bas was composed of 131 patients who received basiliximab, and Group Triple enrolled the other 137 patients who did not. Between the two groups, there was no significant difference in the cumulative survival of patients without hepatocellular carcinoma (HCC) or in the cumulative survival of patients with HCC. For patients with benign end-stage liver diseases, Group Bas had more patients with a high risk of short- and medium-term mortality than Group Triple (22.81% vs. 8.85%, p = 0.017), but the survival curves of the two groups were not significantly different. The 1-year incidence of acute rejection was lower in Group Bas, although the difference was not significant (8.75% vs. 15.33%, p > 0.05). In both Group Bas and Group Triple, the level of serum creatinine (Scr) at 1 week posttransplantation was significantly lower than pretransplantation (61.00 vs. 88.50 μmol/l, p < 0.001; 61.50 vs. 74.00 μmol/l, p < 0.001; respectively). There was a significant difference in the pretransplantation Scr between the two groups (88.50 vs. 74.00 μmol/l, p = 0.005), but the values of Scr decreased to the same level 1 week (61.00 vs. 61.50 μmol/l, p > 0.05) and 4 weeks (61.00 vs. 59.00 μmol/l, p > 0.05) after transplantation. Significantly fewer recipients in Group Bas experienced hepatitis B relapse than in Group Triple (2/131 vs. 13/137, p = 0.006).

CONCLUSIONS

A basiliximab-induced immunosuppressive protocol is a safe regimen that achieves similar survival without increasing the acute rejection rate for LT recipients with hepatitis B virus-related diseases. For patients with benign end-stage liver diseases, this regimen reduces medium-term mortality in high-risk patients. This regimen remarkably improves renal function in the first month after LT and is correlated with a decreased hepatitis B recurrence rate in adult patients after LT.

Black hood assisted colonoscopy for detection of colorectal polyps: a prospective randomized controlled study

OBJECTIVE

Colonoscopy is considered as a standard method for detecting various kinds of colorectal polyps. However, conventional colonoscopy (CC) still has chances to miss some lesions. Some scholars have already reported that transparent hood assisted colonoscopy (THAC) can improve the detection rate of colorectal polyps. However, the efficacy of detection of colorectal polyps with black hood assisted colonoscopy (BHAC) is still unclear. In this study, BHAC was compared with CC for evaluating the efficacy of detection of colorectal polyps.

PATIENTS AND METHODS

Between Sep 2014 and Apr 2015, 542 patients underwent CC and meanwhile 534 patients underwent BHAC were enrolled into this prospective randomized controlled study. Comparison of baseline characteristics, cecal intubation time, withdrawal time, total number of detected polyps, detection rate of polyps, location, size, morphology and pathological diagnosis of polyps between these two groups was performed.

RESULTS

Cecal intubation time was significantly shorter in BHAC group than in CC group (6.31 ± 3.51 min vs. 7.05 ± 4.15 min, p = 0.002). The total number of detected polyps and detection rate of polyps were significantly higher in BHAC group than in CC group (349/65.36% vs. 264/48.71%, p = 0.004).

CONCLUSIONS

Compared with CC, BHAC could significantly improve the detection rate of colorectal polyps, and cecal intubation time was significantly reduced by BHAC.

DCD liver transplant infection: experience from a single centre in China

AIM

The purpose of our study was to evaluate the incidence, timing, location and risk factors for bacterial and fungal infections after donation after cardiac death (DCD) liver transplant and clearly delineate any relationship between infection and survival in DCD liver transplant recipients.

METHODS

We retrospectively reviewed 257 consecutive patients undergoing DCD liver transplant between October 2010 and May 2015 at our centre.

RESULTS

A total of 133 patients (51.8%) developed at least one bacterial or fungal infection episode. The predominant infection site was the respiratory tract, followed by the blood stream. Most of the infections occurred within the first week after liver transplant (61.9%). A recipient respiratory support time greater than 7 days (p = 0.041), post-transplant hospital time greater than 24 days (p = 0.002) and renal failure after DCD liver transplant (p = 0.039) were independent predictors of bacterial and fungal infection. The area under the receiver operating characteristic (ROC) curve (AUC) of the transplant infection risk assessment model was 0.788. The 1- and 3-year survival rates for recipients without infection were significantly increased compared with recipients with infection (96.1% and 89.0% vs. 81.5% and 75.9%, p = 0.007).

CONCLUSION

This is the first study that offers detailed data revealing the timing and incidence of bacterial and fungal infection among adult DCD liver transplant recipients. Bacterial and fungal infection occurs at a high rate during the first week after DCD liver transplant, especially in patients with prolonged respiratory support time and renal failure, and infection is related to increased hospital stay.

Efficacy of a quadruple therapy regimen for Helicobacter pylori eradication after partial gastrectomy

We aimed to evaluate the effectiveness and safety of bismuth-containing quadruple therapy plus postural change after dosing for Helicobacter pylori eradication in gastrectomized patients. We compared 76 gastric stump patients with H. pylori infection (GS group) with 50 non-gastrectomized H. pylori-positive patients who met the treatment indication (controls). The GS group was divided into GS group 1 and GS group 2. All groups were administered bismuth potassium citrate (220 mg), esomeprazole (20 mg), amoxicillin (1.0 g), and furazolidone (100 mg) twice daily for 14 days. GS group 1 maintained a left lateral horizontal position for 30 min after dosing. H. pylori was detected using rapid urease testing and histologic examination of gastric mucosa before and 3 months after therapy. Mucosal histologic manifestations were evaluated using visual analog scales of the updated Sydney System. GS group 1 had a higher prevalence of eradication than the GS group 2 (intention-to-treat [ITT]: P=0.025; per-protocol [PP]: P=0.030), and the control group had a similar prevalence. GS group 2 had a lower prevalence of eradication than controls (ITT: P=0.006; PP: P=0.626). Scores for chronic inflammation and activity declined significantly (P<0.001) 3 months after treatment, whereas those for atrophy and intestinal metaplasia showed no significant change. Prevalence of adverse reactions was similar among groups during therapy (P=0.939). A bismuth-containing quadruple therapy regimen plus postural change after dosing appears to be a relatively safe, effective, economical, and practical method for H. pylori eradication in gastrectomized patients.

Gastrointestinal stromal tumors: current translational research and management modalities

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. In recent years, detection of these subepithelial lesions has improved due to advances in endoscopic imaging techniques. Furthermore, developments in immunohistochemical technologies, allowing for reliable differentiation of GISTs from other subepithelial tumors, have improved the understanding of these lesions significantly. Alongside the emergence of these new technologies, clinical management of GISTs has progressed greatly in the last decade. However, major controversies still exist in various aspects of GIST management, such as diagnosis, treatment, and prognosis. This review article provides the current overview of the research status in the management of GISTs.

SKLB-163, a new benzothiazole-2-thiol derivative, exhibits potent anticancer activity by affecting RhoGDI/JNK-1 signaling pathway

Small-molecule inhibitors are an attractive therapeutic approach for most types of human cancers. SKLB-163, a novel benzothiazole-2-thiol derivative, was developed via computer-aided drug design and de novo synthesis. MTT assay showed it had potent anti-proliferative activity on various human cancer cells. Treatment of cancer cells with SKLB-163 induced obvious apoptosis and inhibited proliferation in vitro. SKLB-163 administered p.o. showed a marked antitumor activity in vivo. Proteomic techniques were employed to identify possible drug target proteins. The data showed molecular mechanism of action might be involved in downregulation of RhoGDI, which finally contributed to increased apoptosis and inhibited proliferation. These findings provided the potential value of SKLB-163 as a novel candidate antitumor drug.

Combined folate gene MTHFD and TC polymorphisms as maternal risk factors for Down syndrome in China

We examined whether polymorphisms in the methylenetetrahydrofolate dehydrogenase (MTHFD) and transcobalamin (TC) genes, which are involved in folate metabolism, affect maternal risk for Down syndrome. We investigated 76 Down syndrome mothers and 115 control mothers from Bengbu, China. Genomic DNA was isolated from the peripheral lymphocytes. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFD G1958A and TC C776G. The frequencies of the polymorphic alleles were 24.3 and 19.1% for MTHFD 1958A, 53.9 and 54.2% for TC 776G, in the case and control groups, respectively. No significant differences were found between two groups in relation to either the allele or the genotype frequency for both polymorphisms. However, when gene-gene interactions between these two polymorphisms together with previous studied C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene were analyzed, the combined MTHFR 677CT/TT and MTHFD 1958AA/GA genotype was found to be significantly associated with the risk of having a Down syndrome child [odds ratio (OR) = 3.11; 95% confidence interval (95%CI) = 1.07-9.02]. In addition, the combined TC 776CG and MTHFR 677TT genotype increased the risk of having a child with Down syndrome 3.64-fold (OR = 3.64; 95%CI = 1.28-10.31). In conclusion, neither MTHFD G1958A nor TC C776G polymorphisms are an independent risk factor for Down syndrome. However, the combined MTHFD/MTHFR, TC/MTHFR genotypes play a role in the risk of bearing a Down syndrome child in the Chinese population.

Embryonic-like stem cell derived from adult bone marrow: immature morphology, cell surface markers, ultramicrostructure and differentiation into multinucleated fibers in vitro

Embryonic-like stem cell (ELSC), expressing part of surface markers of human embryonic stem cells, may be a better candidate for cell therapy of degenerative muscular disease than mesenchymal stem cell (MSC). We isolated ELSC and MSC from bone marrow, respectively, and compared their differences in the characteristics and the capacity of myogenic differentiation. Results showed that ELSC could be isolated successfully from 3 adult bone marrow samples by using serum-free medium with 10ng/ml basic fibroblast growth factor (bFGF). At the same cell density, MSC could also be isolated from the same samples by using DMEM/F12 medium containing 10% new cattle serum. However, ELSC appeared as small, morphologically slenderer, upregulated expression of SSEA-4 and ultramicroscopically more immature than MSC derived from the same samples. Immunofluorescent staining and RT-PCR analysis showed ELSC weakly expressed Oct-4, Nanog-3 and Sox-2. Moreover, ELSC and MSC could be induced into long, multinucleated fibers expressing myogenin and myosin heavy chain (MHC) in myogenic differentiation medium, but by day 10, proportion of multinucleated fibers positive for MHC was respectively 25.0%+/-6.9% and 13.8%+/-7.6% in ELSC and MSC culture. These data suggest that bone marrow derived ELSC represent an ideal candidate for cell therapy of degenerative muscular disease.

[Abuse of "pheticol" and its interference to the analysis of methamphetamine]

The study was to eliminate interference from ephedrine in the analysis of methamphetamine. The extraction procedure for methamphetamine was modified to include an oxidation step (2 ml urine specimen was treated with 0.5 ml of 1 mol/L phosphate buffer (pH 6.8) and 0.5 ml 0.3 mol/L sodium periodate). Results showed that ephedrine could be oxidized in the presence of periodate ions into smaller fragments while leaving methamphetamine intact. It is recommended that specimens be treated with sodium periodate prior to extraction in order to eliminate any interference caused by ephedrine.

[Study of distribution and metabolism of methamphetamine in hair of guinea pig]

OBJECTIVE

To study the distribution and metabolism of methamphetamine in the hair of guinea pig.

METHODS

Determination of methamphetamine and its metabolite amphetamine in hair was performed by GC/MS and GC/NPD. Concentration-time course of methamphetamine and amphetamine in hair of guinea were recorded. Relationship between hair color, administrated dose and drug concentration in hair were also discussed.

RESULTS

The concentration of amphetamine is higher than the concentration of methamphetamine in the hair of guinea administrated a single dose or seven doses of methamphetamine. The concentration of methamphetamine and amphetamine were significantly related with administration dose and the incorporation rate into white and brown hair is much poorer than that of black hair.

CONCLUSION

Administration methods, dose and the color of hair affect the concentration of methamphetamine and amphetamine.

The stability of tetramine, morphine and meperidine in formalin solution

The stability of tetramine, morphine and meperidine in formalin solution is an important factor for drug analysis in forensic investigation. In this paper, the tissues (liver, kidney, lung and heart) from poisoned rabbits were immersed in 50 ml 10% formalin solutions for 4 months before examination. We compared the levels of tetramine, morphine, meperidine and the main metabolite normeperidine, measured by GC/NPD or GC-MS, in frozen rabbit tissues, formalin-fixed rabbit tissues, and formalin solution. There was a decrease in the levels of tetramine, morphine, meperidine in formalin-preserved tissues compared with the levels of these drugs in the frozen tissues. It is suggested that the formalin-fixed tissues and formalin solution should be analyzed at the same time to assure the accurate results.

[Detection of antidepressant and antipsychotic drugs in human hair and evaluation of the results]

The presence of therapeutic drugs in the hair of psychiatric patients was investigated, and the method for simultaneous determination of antidepressant and antipsychotic drugs by GC/NPD and GC/MS was also established. Eight different psychotroic drugs were detected from the hair of 32 subjects, and chlorpromazine and clozapine concentrations in the hair were found to be dependent on the dosage and the correlation coefficients were 0.8047 (P < 0.001, n = 16) and 0.7097 (P < 0.001, n = 16) respectively. Segmental analysis demonstrated that there was a correlation between the subject's drug exposure history and the distribution of drug along the hair shaft.

[Segmental analysis of hair from meperidine abusers and evaluation of the results]

Using meperidine abusers as subjects for this study, we detected in hair meperidine and its metabolites normeperidine, N-OCH3-meperidine and N-AC-meperidine. The content of meperidine and normeperidine of 60 abusers were 103 +/- 130 ng/mg and 117 +/- 143 ng/mg respectively. Meperidine was stably present in hair for at least 20 months. Normeperidine level decreased from hair root to tip. The segmental analysis of hair revealed that there were correlations between the drug abuse history and the distribution of drug along the hair shaft, and between the dose of meperidine and its content presented in hair.

[Determination of heroin metabolites in biological fluids, tissues and hair of heroin addicts using GC/MS-SIM]

Using GC/MS-SIM, we examined morphine distribution in human bodies of 2 delayed death cases and analyzed content of morphine and 6-acetylmorphine (MAM) in hair specimens of 7 cases. After hydrolysis and extraction, MOR and 6-MAM were derived with acetic anhydride or BSTFA and then the derivatives were qualitatively and quantitatively analyzed by GC/MS-SIM. The results indicated that urine, bile and liver were the best samples to reveal the heroin-related deaths. Hair analysis has its unique advantage for its long time of abusing monitor, compared to biological fluids.

[Study on the radioligand binding assay of cholecystokinin receptor in rat cerebral cortex]

A radioligand binding assay system for determining the characterization of CCK receptor is presented. Using Bolton-Hunter reagent, we prepared a biologically active, specific 125I-BH-CCK8. The iodination mixture was then transferred to a column of Sephadex G-25 and examined by silica thin layer chromatography. Its specific activity and radiochemical purity were 3.4 TBq/mmol and 96% respectively. Binding of 125I-BH-CCK8 to the membrane of rat cerebral cortex was rapid, reversible, time-temperature dependent, saturable and specific. The labeled CCK was shown to have biological activity as measured by the CCK receptor radioassay. Under our laboratorial conditions, the CCK binding required an hour to reach equilibrium at 4 degrees C. We chose polyethylene glycol 6,000 and gamma-globulin protein for the separation of B and F. Scatchard plot of CCK binding was linear with a Kd value of 1.098 nmol/L and Bmax of 197.5 fmol/mg protein. The results of this study support the stand-point that CCK may function as a regulatory peptide in brain and hence may be of use for clarifying the CCK receptor's function in central nervous system.

[Determination of metabolites of heroin in urine and discrimination of heroin abuse]

This article describes a sensitive method that detects morphine, 6-monoacetylmorphine, morphine-3-glucuronide and codeine in urine for qualifying the abuse of heroin. The analytes were extracted by solid phase C18. The limits of detection (LOD) for morphine and codeine were 50 ng/ml and 50 ng/ml, respectively. The RSD of morphine and codeine were 11.3% (n = 5), and 14.2% (n = 5) respectively. For urine, it does not need to be hydrolyzed before extracted, and for all analytes, also need not to be derivated. The difference ratio of morphine and codeine in the chromatography can be used to discriminate between the abuse of heroin and the administration of compound liquorice mixture.

[Analysis of penicillins in whole blood by reversed high-performance liquid chromatography]

A reversed-HPLC method was established to determinate penicillins in whole blood. Thiamphenicol as internal standard was added to 0.5 ml blood. Proteins in blood were precipitated with acetonitrile, then the separate supernatant was directly injected onto the chromatography column. The range of five penicillins' linearities was 0.9918 to 0.9996, their range of relative recovery was 91.75% to 107.33%, their CV was 3.56% to 9.85%. Effects of different storage temperatures on the stability of analytes and interference of other antibiotics were also studied.

[Zinc deficiency inhibited the proliferation and differentiation of rat osteoblast in vitro]

The effect of zinc deficiency on proliferation and differentiation of rat osteoblast was studied in vitro. The osteoblasts were isolated from the rat calvaria, and were subcultured in DMEM medium. Zinc deficiency model in cell culture was made by chelating zinc from the medium with a special chelator TPEN. Incorporation of 3H-thymidine was measured to show the DNA synthesis at different time point, and cell cycle was analyzed by flow cytometry. A histochemistry method was used to detect changes of osteoblast cytoskeleton. Incorporation of 3H-proline was measured to show the synthesis of collagen. Alkaline phosphatase activity (AKP) and osteocalcin content were measured by enzyme dynamics method and radioimmunoassay respectively. The results showed that the incorporation of 3H-thymidine in the zinc deficient group was significantly less than that in the control group at different time points. The cells were blocked at G2/M phase of cell cycle, which is related to the impairment of cytoskeleton. Collagen synthesis, osteocalcin content and AKP activity in the zinc deficient group were reduced significantly as compared with those in the control group. But no differences in all the measurements were observed between the control group and the group of zinc deficiency supplemented with zinc. Therefore, it was concluded that zinc deficiency inhibited the proliferation and differentiation of rat osteoblast in vitro.

The development of self-perceptions of ability and achievement goals and their relations in physical education

This study examined the development of self-perceptions of ability and achievement goals and their relationships in physical education. Three hundred and eight students in 4th, 8th, and 11th grades completed questionnaires assessing their goal orientations, conceptions of ability, and perceived competence in physical education. Analyses assessing grade-related changes in conceptions of ability and achievement goals showed that as the students progressed from grades 4 through 11, they were more likely to: (a) interpret ability as a stable capacity that may limit or increase the effect of effort on performance and (b) become ego-oriented. Analyses assessing relationships between variables of interest across grade level revealed that achievement goals were related to different conceptions of ability, students' self-ratings were significantly positively correlated to their teachers' ratings of their competence, and no consistent relationships emerged between achievement goals and perceived competence.

[Analysis and assessment of meperidine and normeperidine concentrations in urine]

In this study, urine concentrations of meperidine and normeperidine after a single therapeutic dose of meperidine in 5 healthy volunteers have been measured and compared the results to those in meperidine addicts. The results showed that there was a significant difference between two groups in the ratio of metabolite to parent drug. If can be concluded that the ratio should be aid in making a cause of meperidine injection.