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1.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 41(11): 825-831, 2023 Nov 20.
Article in Chinese | MEDLINE | ID: mdl-38073209

ABSTRACT

Objective: To analyze the disease burden and change trend of lung cancer attributable to chromium in Chinese population from 1990 to 2019, and to provide reference for the formulation of health policies and strategies of disease prevention and control. Methods: In October 2022, using the data and findings of the burden of disease, injury and risk factor published in the Global Burden of Disease Study 2019 (GBD 2019), the burden of lung cancer and its changes caused by occupational hexavalent chromium exposure in Chinese population from 1990 to 2019 were analyzed according to year and gender. The average age structure of the world population was used as the standard population to calculate standardized indicators, and then compared with the global population. Results: The incidence number, death number, disability adjusted life years (DALY) of lung cancer attributable to chromium in Chinese population of 2019 were 833 cases, 790 cases and 22118 person years, respectively. Compared with 1990 (257 cases, 277 cases, 8631 person years), the increase was 224.1%, 185.2%, 156.3%, higher than the global level (101.0%, 134.2%, 117.2%). The standardized morbidity, mortality and DALY rates of lung cancer attributable to chromium in Chinese population of 2019 were 0.059/100000, 0.056/100000 and 1.555/100000, which respectively increased by 169.7%, 137.4%, 113.3% in comparison with that of 1990 (0.022/100000, 0.023/100000 and 0.729/100000). The average annual percent changes were 18.8%, 15.1% and 13.5%, which were higher than the global level (5.7%, 8.4% and 7.0%). In 2019, the DALY caused by chromium-related lung cancer in the Chinese population accounted for 0.0058% (22118/382205568) of the all-cause disease burden in the Chinese population, and 51.8% (22118/42718) of the global population. In 2019, the disease burden of lung cancer attributable to chromium was higher in males than in females, the number of incidence, death and DALY were 576 cases (69.1%), 525 cases (66.5%) and 14717 person years (66.5%), respectively. Conclusion: In 2019, the proportion of disease burden caused by lung cancer attributable to chromium in the Chinese population is low, but it accounts for a high proportion of the global population burden of lung cancer attributable to chromium, and the standardized incidence, mortality and DALY rates show an increasing trend year by year from 1990 to 2019.


Subject(s)
Disabled Persons , Lung Neoplasms , Male , Female , Humans , Lung Neoplasms/epidemiology , Quality-Adjusted Life Years , Cost of Illness , China/epidemiology
2.
RSC Adv ; 8(2): 877-884, 2018 Jan 02.
Article in English | MEDLINE | ID: mdl-35538995

ABSTRACT

A highly crystalline nanosized spinel LiMn2O4/3DG composite cathode material for high rate lithium ion batteries was successfully prepared by mixing spinel LiMn2O4 particles with reduced graphene oxide (3DG). Spinel LiMn2O4 and reduced three-dimensional graphene oxide were synthesized using a hydrothermal method and freeze-drying technology, respectively. The structure, morphology and electrochemical performance of the synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge techniques. The results showed that the LiMn2O4/3DG composites exhibited excellent rate capability and stable cycling performance. The discharge capacity was 131 mA h g-1 and the capacity remains at 89.3% after 100 cycles at a 0.5 C rate, while the discharge capacity was 90 mA h g-1 at 10 C. Compared with spinel LiMn2O4 materials, the LiMn2O4/3DG composites showed obvious improvement in electrochemical performance.

3.
J Anim Sci ; 91(11): 5229-39, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24045481

ABSTRACT

Ovarian steroid hormones regulate follicular growth and atresia. This study aims to determine whether key ovarian sterol-regulatory genes are differentially expressed in Hu sheep under different short-term nutritional regimens. Estrus was synchronized using intravaginal progestagen sponges. The ewes were assigned randomly to 3 groups. On d 6 to 12 of their estrous cycle, the control (CON) group received a maintenance diet (1.0×M), the supplemented (SUP) group received 1.5×M, and the restricted (R) group received 0.5×M. On d 7 to 12, blood samples were taken. The sheep were slaughtered at the end of the treatment, and their organs and ovaries were collected. The plasma concentrations of urea (P<0.01), total cholesterol (P<0.01), low-density lipoprotein cholesterol (P<0.01), NEFA (P<0.01), FSH (P<0.05), and estradiol (P<0.05) increased with decreasing dietary intake, whereas plasma triglyceride (P<0.01) and triiodothyronine (T3) concentrations decreased (P<0.05). The ewes in the R group had higher spleen weight and percentage of spleen to BW and lower liver and small intestine weights and percentage of liver/stomach to BW than the SUP group ewes (P<0.05). Nutritional restriction decreased the cytochrome p450 (CYP17A1) and estrogen receptor 1 (ESR1) mRNA expression (P<0.05) and increased the cytochrome p450 aromatase (CYP19A1) mRNA expression (P<0.05) in follicles>2.5 mm. Follicle size affected the mRNA expression of very low density lipoprotein receptor (VLDLR), estrogen receptor 2 (ESR2), FSH receptor (FSHR), CYP17A1, and CYP19A1 (P<0.05). In conclusion, we suggest that a potential mechanism by which short-term negative energy balance inhibits follicular growth may involve responses to disrupted reproductive hormone concentrations and influenced the intrafollicular expression of CYP17A1, CYP19A1, and ESR1. This result may be due to increased plasma urea and lipid concentrations.


Subject(s)
Gene Expression Regulation/physiology , Gonadal Steroid Hormones/biosynthesis , Lipids/blood , Nutritional Status , RNA, Messenger/metabolism , Sheep/genetics , Animal Feed , Animal Nutritional Physiological Phenomena , Animals , Body Weight , Diet/veterinary , Estrus Synchronization , Female , Luteal Phase/physiology , Ovary/physiology , Progestins/administration & dosage , Progestins/pharmacology , RNA, Messenger/genetics , Sheep/blood , Sheep/metabolism , Urea/blood
4.
Genet Mol Res ; 12(2): 1490-500, 2013 May 06.
Article in English | MEDLINE | ID: mdl-23765956

ABSTRACT

Liver receptor homologue 1 (Lrh-1) is a member of the nuclear receptor belonging to the second subfamily of the nuclear receptor family 5A (NR5A), also named NR5A2, which is important for lipid homeostasis, embryogenesis, and regulation of aromatics. The present study aimed to understand the sequence of ovine Lrh-1 and the expression traits in reproductive organ tissues. Initially, we cloned Lrh-1 from the liver of Hu sheep through degenerate primer of reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. Characteristic functional domains of DNA binding and ligand binding, conserved among transcription factors of the nuclear receptor superfamily, were identified in Lrh-1 of Hu sheep. The Lrh-1 protein levels in the tissues detected by Western blotting correlated significantly with the transcript levels measured by quantitative real-time polymerase chain reaction (qRT-PCR). To understand the Lrh-1 expression change in the hypothalamus and hypophysis during the estrous cycle, we analyzed the expression pattern of Lrh-1 mRNA and protein by qRT-PCR and Western blotting, respectively. This analysis revealed that Lrh-1 expression in the hypothalamus was highest during the metestrus phase, while the Lrh-1 level was similar during other phases. In the hypophysis, the expression was significantly different during the 4 phases of the estrous cycle but highest during the estrus phase, significantly correlating with FSH concentration. These results indicate that Lrh-1 expression is correlated with gonadotropic hormone secretion, influencing follicular formation in the ovary.


Subject(s)
Gene Expression Regulation , Receptors, Cytoplasmic and Nuclear/genetics , Sheep/genetics , Amino Acid Sequence , Animals , China , Cloning, Molecular , Estrous Cycle , Female , Gene Expression Profiling , Hypothalamo-Hypophyseal System/metabolism , Liver/metabolism , Molecular Sequence Data , Oviducts/metabolism , Receptors, Cytoplasmic and Nuclear/blood , Receptors, Cytoplasmic and Nuclear/chemistry , Sequence Alignment , Sheep/blood , Sheep/classification
5.
Parasite Immunol ; 34(8-9): 404-11, 2012.
Article in English | MEDLINE | ID: mdl-22651670

ABSTRACT

Na-ASP-2 is a major protein secreted by infective third-stage larvae (L3) of the human hookworm Necator americanus upon host entry. It was chosen as a lead vaccine candidate for its ability to elicit protective immune responses. However, clinical development of this antigen as a recombinant vaccine was halted because it caused allergic reactions among some of human volunteers previously infected with N. americanus. To prevent IgE-mediated allergic reactions induced by Na-ASP-2 but keep its immunogenicity as a vaccine antigen, we designed and tested a genetically engineered fusion protein, Fcγ/Na-ASP-2, composed of full-length Na-ASP-2 and truncated human IgG Fcγ1 that targets the negative signalling receptor FcγRIIb expressed on pro-allergic cells. The chimeric recombinant Fcγ/Na-ASP-2 protein was expressed in Pichia pastoris and shared the similar antigenicity as native Na-ASP-2. Compared to Na-ASP-2, the chimeric fusion protein efficiently reduced the release of histamine in human basophils sensitized with anti-Na-ASP-2 IgE obtained from individuals living in a hookworm-endemic area. In dogs infected with canine hookworm, Fcγ/Na-ASP-2 resulted in significantly reduced immediate-type skin reactivity when injected intradermally compared with Na-ASP-2. Hamsters vaccinated with Fcγ/Na-ASP-2 formulated with Alhydrogel(®) produced specific IgG that recognized Na-ASP-2 and elicited similar protection level against N. americanus L3 challenge as native Na-ASP-2.


Subject(s)
Basophils/immunology , Histamine Release , Immunization , Immunoglobulin E/immunology , Immunoglobulin Fc Fragments/immunology , Necator americanus/immunology , Vaccination/methods , Animals , Antigens, Helminth/genetics , Antigens, Helminth/immunology , Cricetinae , Dogs , Gene Expression , Humans , Hypersensitivity/prevention & control , Immunoglobulin Fc Fragments/genetics , Immunoglobulins , Pichia/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Skin/pathology , Vaccination/adverse effects
6.
Theor Appl Genet ; 118(2): 313-25, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18853131

ABSTRACT

A set of 142 winter wheat recombinant inbred lines (RILs) deriving from the cross Heshangmai x Yu8679 were tried in four ecological environments during the seasons 2006 and 2007. Nine agronomic traits comprising mean grain filling rate (GFR(mean)), maximum grain filling rate (GFR(max)), grain filling duration (GFD), grain number per ear (GNE), grain weight per ear (GWE), flowering time (FT), maturation time (MT), plant height (PHT) and thousand grain weight (TGW) were evaluated in Beijing (2006 and 2007), Chengdu (2007) and Hefei (2007). A genetic map comprising 173 SSR markers and two EST markers was generated. Based on the genetic map and phenotypic data, quantitative trait loci (QTL) were mapped for these agronomic traits. A total of 99 putative QTLs were identified for the nine traits over four environments except GFD, PHT and MT, measured in two environments (BJ07 and CD07), respectively. Of the QTL detected, 17 for GFR(mean), 16 for GFR(max), 21 for TGW and 10 for GWE involving the chromosomes 1A, 1B, 2A, 2D, 3A, 3B, 3D, 4A, 4D, 5A, 5B, 6D and 7D were identified. Moreover, 13 genomic regions showing pleiotropic effects were detected in chromosomes 1A, 1B, 1D, 2A, 2B, 2D, 3A, 3B, 4B, 4D, 5B, 6D and 7D; these QTL revealing pleiotropic effects may be informative for a better understanding of the genetic basis of grain filling rate and other yield-related traits, and represent potential targets for multi-trait marker aided selection in wheat.


Subject(s)
Quantitative Trait Loci , Triticum/genetics , Chromosome Mapping , Chromosomes, Plant , Genetic Linkage , Genetic Markers , Inbreeding , Phenotype , Time Factors , Triticum/anatomy & histology , Triticum/growth & development
7.
Article in Chinese | MEDLINE | ID: mdl-12571934

ABSTRACT

OBJECTIVE: To verify the efficacy of abendazole emulsion, a new formulation of abendazole, in treatment of human cystic echinococcosis. METHODS: 212 patients with liver cystic echinococcosis were treated orally with albendazole emulsion at a daily dose of 10 mg/kg or 12.5 mg/kg for 3 to 12 months or over one year. The therapeutic efficacy was mainly evaluated by image feature examined with B ultrasound examination, a short-term efficacy at the completion of treatment and a long-term efficacy followed-up for 1-4 years. RESULTS: In 212 patients treated with albendazole emulsion at a daily dose of 10 mg/kg and 12.5 mg/kg, the average cure rate, improved rate and the rate of no avail were 74.5%, 99.1% and 0.9% respectively after termination of the treatment, and the average long-term rates were 83.1%, 89.3% and 0.6% respectively. Recurrence occurred in 18 patients(10.2%). The results indicated that the best efficacy was seen in patients treated with albendazole 12.5 mg/kg daily for 9 months. Better response was also found when the recurrent patients were re-treated with albendazole. CONCLUSION: The efficacy of albendazole emulsion on patients with liver cystic echinococcosis is much better than that of albendazole tablet or capsule and mebendazole. Meanwhile, the efficacy of albendazole emulsion is stable with less adverse effects. The results suggest that albendazole emulsion could be the drug of choice for treatment of cystic hydatid disease.


Subject(s)
Albendazole/therapeutic use , Anthelmintics/therapeutic use , Echinococcosis, Hepatic/drug therapy , Albendazole/administration & dosage , Anthelmintics/administration & dosage , Emulsions , Female , Follow-Up Studies , Humans , Male , Treatment Outcome
9.
Parasitol Today ; 16(3): 122-6, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10689333

ABSTRACT

The fight against schistosomiasis in China has been very effective in reducing the number of infections across the country. However, the drug of choice, praziquantel, has no prophylactic effect, which reduces its efficacy in high transmission areas. This situation has prompted efforts to find prophylactic compounds, the most promising of which is the drug artemether. In this article, Xiao Shuhua, Mark Booth and Marcel Tanner review the results of laboratory tests and field trials of artemether against schistosomiasis in China.


Subject(s)
Artemisinins , Schistosomiasis japonica/prevention & control , Schistosomicides/therapeutic use , Sesquiterpenes/therapeutic use , Animals , Artemether , China , Dogs , Rabbits , Schistosoma japonicum/drug effects , Schistosoma japonicum/growth & development
10.
Yi Chuan Xue Bao ; 27(12): 1080-3, 2000.
Article in Chinese | MEDLINE | ID: mdl-11209700

ABSTRACT

The barley chromosome in wheat was identified by genomic in situ hybridization (GISH) in which biotin labelled total genomic DNA of barley Betzes was used as probe and the unlabelled total DNA of common wheat Chinese Spring (CS) as blocking DNA. A series of wheat materials were tested as follows: two disomic alien substitution and monosomic alien addition lines, 2n = 43; two monosomic alien substitution lines, 2n = 42; seven disomic alien substitution lines, 2n = 42. RFLP probe psr131 on the short arm of the homologous group 2 was used to analyze the barley chromosome in wheat. The result indicated that there was a same band in barley Betzes and substitution line A5. The chromosome 2A of A5 was substituted by the chromosome 2H of barley. These materials will be useful in transferring the valuable genes in the chromosome 2H to wheat.


Subject(s)
Chromosomes , Hordeum/genetics , In Situ Hybridization , Polymorphism, Restriction Fragment Length , Triticum/genetics
11.
Article in English | MEDLINE | ID: mdl-12567467

ABSTRACT

OBJECTIVE: To obtain the genetic information on Necator americanus and to search for the purpose genes. METHODS: mRNA was isolated from the third stage larvae of Necator americanus maintained in hamsters. Double strand cDNA was synthesized and ligated to lambda ZAPII vector to construct the cDNA library. Expressed sequence tages (ESTs) were obtained by single pass sequencing of randomly isolated cDNA clones from the established library. RESULTS: A cDNA library of N. americanus was successfully constructed with high recombinant efficiency. The titer of unamplified library was 1 x 10(7). The insert size was about 750-3,000 bp. Of 11 ESTs obtained from the library, 7 have a significant homology with certain functional genes. CONCLUSION: A high quality and high representative cDNA library of N. americanus was constructed at the first time and some functional genes were identified from the library by ESTs.


Subject(s)
DNA, Complementary/genetics , Gene Library , Necator americanus/genetics , Animals , Cricetinae/parasitology , Expressed Sequence Tags , Larva/genetics , RNA, Messenger/genetics , RNA, Messenger/isolation & purification
12.
Article in Chinese | MEDLINE | ID: mdl-12567607

ABSTRACT

OBJECTIVE: To study the effect of artemether (Art) on phosphoglucomutase (GPM), aldolase (ALD), phosphoglycerate mutase (PGM) and enolase (ENO) of Schistosoma japonicum harbored in mice. METHODS: Mice infected with S. japonicum cercariae for 4-5 wk were treated ig with Art 100 mg/kg or 300 mg/kg and killed 24 h or 48 h after treatment for collection of worms. The activities of GPM, ALD, PGM and ENO in female and male worms were measured by the formation of NADPH or consumption of NADH. RESULTS: After the worms were exposed in vivo to Art 100 mg/kg for 24 h, the GPM, ALD, PGM and ENO activities in female worms were significantly decreased by 15%, 19%, 50% and 46%, respectively, while in male worms only the PGM and ENO activities were markedly decreased by 22% and 32%, respectively. Following exposure of the worms to Art 100 mg/kg for 48 h, the GPM and ALD activities in male worms were also significantly reduced by 21% and 18%, respectively, while the activities of GPM, ALD, PGM and ENO in female worms and those of PGM and ENO in male worms declined progressively with time. After the worms were exposed in vivo to Art 300 mg/kg for 24-48 h, all the activities of the above-mentioned enzymes in female and male worms declined significantly in a time-related pattern. CONCLUSION: Art showed an apparently inhibitory effect on GPM, ALD, PGM and ENO in female schistosomes.


Subject(s)
Artemisinins/pharmacology , Schistosoma japonicum/enzymology , Schistosomicides/pharmacology , Sesquiterpenes/pharmacology , Animals , Artemether , Female , Fructose-Bisphosphate Aldolase/metabolism , Male , Mice , Phosphoglucomutase/metabolism , Phosphoglycerate Mutase/metabolism , Phosphopyruvate Hydratase/metabolism
13.
Article in Chinese | MEDLINE | ID: mdl-12567696

ABSTRACT

OBJECTIVE: To study the effect of artemether on several enzymes involved in carbohydrate metabolism of Schistosoma japonicum. METHODS: Mice infected with Schistosoma japonicum cercariae for 4-5 weeks were administered intragastrically with artemether 300 mg/kg and killed 24-72 h after medication. The supernatant fluids of female and male worm homogenates were prepared for determining 9 essential enzymes of carbohydrate metabolism by using horizontal starchgel electrophoresis. RESULTS: The activities of 8 out of 9 enzymes (i.e. hexokinase, aldolase, glucosephophate isomerase, malate dehydrogenase, malic enzyme, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and mannose-6-phosphate isomerase) in female worms from artemether-treated mice were obviously inhibited 24-72 h after treatment. In male worms, only aldolase, mannose-6-phosphate isomerase and glucose 6-phosphate dehydrogenase were slightly inhibited. CONCLUSION: Artemether displayed apparent effects on the carbohydrate metabolism of female schistosomes.


Subject(s)
Artemisinins/pharmacology , Fructose-Bisphosphate Aldolase/metabolism , Hexokinase/metabolism , Schistosoma japonicum/enzymology , Schistosomicides/pharmacology , Sesquiterpenes/pharmacology , Animals , Artemether , Female , Malate Dehydrogenase/metabolism , Mannose-6-Phosphate Isomerase/metabolism , Mice , Phosphogluconate Dehydrogenase/metabolism , Schistosomiasis japonica/enzymology
15.
Yao Xue Xue Bao ; 35(10): 721-4, 2000 Oct.
Article in Chinese | MEDLINE | ID: mdl-11372434

ABSTRACT

AIM: To study the pharmacokinetics of epristeride (EPR) in rats and Beagle dogs. METHODS: The concentrations of EPR in biological samples were determined by an HPLC method with UV detection. RESULTS: The concentration-time curves in rat serum showed two peak concentrations after i.g. doses of 10, 20 and 40 mg.kg-1. The Tpeak1 and Tpeak2 were attained within 0.5-1 h and 3-4 h, respectively. The elimination half-life(T1/2 beta) was 2.43-3.14 h. The Tpeak and T1/2 beta in Beagle dogs were 1 h and 5 h, respectively. EPR was shown to be widely distributed to various tissues after i.g. dose of 20 mg.kg-1. The concentrations in most tissues at 3 h were higher than those of 6 h. The excretion of parent drug in urine amounted to only 0.09% of the dosage and in feces to 42.9% within 24 h after dosing. The biliary excretion were mainly metabolites and only 0.14% of parent drug of the dosage within 12 h. Plasma protein binding ratio of EPR was 92.3% at the concentration range of 50-3,000 ng.mL-1. CONCLUSION: The absorption of EPR was shown to be of first order processes at doses of 10-40 mg.kg-1, both the Cmax and AUC increased proportionally with the dosages. EPR was shown to be widely distributed to the various tissues and mainly eliminated via the feces and bile.


Subject(s)
Androstadienes/pharmacokinetics , Animals , Dogs , Half-Life , Male , Protein Binding , Rats , Rats, Wistar , Tissue Distribution
16.
Yao Xue Xue Bao ; 35(10): 770-3, 2000 Oct.
Article in Chinese | MEDLINE | ID: mdl-11372445

ABSTRACT

AIM: To study the pharmacokinetic properties of sodium bimetrondazole glycinate (CMNa) in animals. METHODS: The concentrations of CMNa and its metabolite metronidazole in biological samples were determined by an HPLC method with UV detection. RESULTS: The transformation studies in vitro indicated that the CMNa transformation rate and metronidazole generation rate in whole blood at 90 min were 91.8% and 67.3%, respectively. After single i.v. doses of 57.3, 171.9 and 515.7 mg.kg-1 CMNa in mice, the T1/2 beta of the parent drug was 0.5, 0.8 and 1.0 min, the T1/2 beta of metronidazole was 63.2, 68.2 and 64.3 min. After a single i.v. dose of 171.9 mg.kg-1 CMNa in rats, the levels of CMNa and metronidazole in various tissues were higher at 2 and 5 min. The urinary excretion of the parent drug and metronidazole were 8.4% and 16.7% of the dose, the biliary excretion were 11.5% and 5.1% and the fecal excretion were 0.14% and 0.03%, respectively. The average plasma protein binding ratio (PPBR) of CMNa was 14.2%. CONCLUSION: CMNa was rapidly metabolized into metronidazole in vivo. The levels of Cmax and AUC of the parent drug and metronidazole increased proportionally with increasing doses. CMNa and metronidazole were predominantly excreted with the urine and bile.


Subject(s)
Metronidazole/analysis , Metronidazole/pharmacokinetics , Radiation-Sensitizing Agents/pharmacokinetics , Animals , Female , Male , Metronidazole/analogs & derivatives , Mice , Rats , Rats, Sprague-Dawley
17.
Zhongguo Yao Li Xue Bao ; 20(8): 750-4, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10678112

ABSTRACT

AIM: To study the effect of artemether (Art) on phosphorylase (PP), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G-6-PDH), and adenosine triphosphatase (ATPase) of S japonicum. METHODS: Mice infected with S. japonicum cercariae for 32-38 d were treated i.g. with Art 100-300 mg.kg-1 and killed 24-72 h after treatment for collection of schistosomes. The activities of PP, LDH, and G-6-PDH were measured by the formation of NADH or NADPH. The activity of ATPase was measured by the rate of release of inorganic phosphate (Pi) from ATP at 37 degrees C. RESULTS: After infected mice were treated i.g. with Art 300 mg.kg-1 for 24-48 h, the activities of total PP and PPa (active form) increased markedly in both male and female worms, while PPb (inactive form) showed no or only a slight increase. At 24-72 h after the above-mentioned mice were treated i.g. with Art 100-300 mg.kg-1, the inhibitory rates of LDH and G-6-PDH were 9%-59% (male) and 41%-75% (female) as well as 22%-42% (male) and 74%-89% (female), respectively. When Art 300 mg.kg-1 was given to infected mice for 24 h, only the activity of Mg(2+)-ATPase showed marked inhibition in both male and female worms. At 48 h, the Ca(2+)-ATPase, Mg(2+)-ATPase, and Na(+)-K(+)-ATPase were all inhibited, the inhibitory rates of 17% (male) and 19% (female), 32% (male) and 48% (female) as well as 29% (male) and 44% (female), respectively. CONCLUSION: In schistosomes, the increase in the activity of AMP-independent PPa induced by Art may enhance the decomposition of glycogen and the inhibition of LDH by Art could reduce the formation of lactate. Moreover, Art exerts a potent inhibition on the G-6-PDH activity of the female S japonicum.


Subject(s)
Artemisinins , Glucosephosphate Dehydrogenase/metabolism , L-Lactate Dehydrogenase/metabolism , Phosphorylases/metabolism , Schistosoma japonicum/enzymology , Sesquiterpenes/pharmacology , Adenosine Triphosphatases/metabolism , Animals , Artemether , Female , Male , Mice , Schistosomicides/pharmacology
18.
EMBO J ; 17(21): 6359-67, 1998 Nov 02.
Article in English | MEDLINE | ID: mdl-9799243

ABSTRACT

SR proteins are a conserved family of splicing factors that function in both constitutive and activated splicing. We reported previously that phosphorylation of the SR protein ASF/SF2 enhances its interaction with the U1 snRNP-specific 70K protein and is required for the protein to function in splicing, while other studies have provided evidence that subsequent dephosphorylation can also be required for SR protein function, at least in constitutive splicing. We now show that the phosphorylation status of ASF/SF2 can differentially affect several properties of the protein. In keeping with a dynamic cycle of phosphorylation-dephosphorylation during splicing, ASF/SF2 phosphorylation was found to affect interaction with several putative protein targets in different ways: positively, negatively or not at all. Extending these results, we also show that, in contrast to constitutive splicing, dephosphorylation is not required for ASF/SF2 to function as a splicing activator. We discuss these results with respect to the differential protein-protein interactions that must occur during constitutive and activated splicing.


Subject(s)
Drosophila Proteins , Nuclear Proteins/metabolism , RNA Splicing/genetics , Adenosine Triphosphate/analogs & derivatives , Adenosine Triphosphate/metabolism , Animals , Cell Extracts , DNA-Binding Proteins/genetics , Drosophila/metabolism , Gene Products, tat/genetics , HeLa Cells , Humans , Insect Proteins/genetics , Phosphoproteins/metabolism , Phosphorylation , Protein Binding , RNA Precursors/genetics , RNA, Viral/genetics , RNA-Binding Proteins/metabolism , Recombinant Fusion Proteins/genetics , Ribonucleoproteins/metabolism , Serine-Arginine Splicing Factors , Splicing Factor U2AF
19.
Genes Dev ; 12(14): 2222-33, 1998 Jul 15.
Article in English | MEDLINE | ID: mdl-9679066

ABSTRACT

The SR proteins constitute a family of splicing factors, highly conserved in metazoans, that contain one or two amino-terminal RNA-binding domains (RBDs) and a region enriched in arginine/serine repeats (RS domain) at the carboxyl terminus. Previous studies have shown that SR proteins possess distinct RNA-binding specificities that likely contribute to their unique functions, but it is unclear whether RS domains have specific roles in vivo. Here, we used a genetic system developed in the chicken B cell line DT40 to address this question. Expression of chimeric proteins generated by fusion of the RS domains of heterologous SR proteins, or a human TRA-2 protein, with the RBDs of ASF/SF2 allowed cell growth following genetic inactivation of endogenous ASF/SF2, indicating that RS domains are interchangeable for all functions required to maintain cell viability. However, a chimera containing the RS domain from a related splicing factor, U2AF65, could not rescue viability and was inactive in in vitro splicing assays, suggesting that this domain performs a distinct function. We also used the DT40 system to show that depletion of ASF/SF2 affects splicing of specific transcripts in vivo. Although splicing of several simple constitutive introns was not significantly affected, the alternative splicing patterns of two model pre-mRNAs switched in a manner consistent with predictions from previous studies. Unexpectedly, ASF/SF2 depletion resulted in a substantial increase in splicing of an HIV-1 tat pre-mRNA substrate, indicating that ASF/SF2 can repress tat splicing in vivo. These results provide the first demonstration that an SR protein can influence splicing of specific pre-mRNAs in vivo.


Subject(s)
Nuclear Proteins/genetics , RNA Splicing , Alternative Splicing , Animals , Binding Sites , Cell Line , Chickens , Gene Products, tat/genetics , HIV-1/genetics , HeLa Cells , Humans , RNA Precursors , RNA, Messenger , RNA-Binding Proteins , Serine-Arginine Splicing Factors , tat Gene Products, Human Immunodeficiency Virus
20.
Zhongguo Yao Li Xue Bao ; 19(3): 279-81, 1998 May.
Article in English | MEDLINE | ID: mdl-10375745

ABSTRACT

AIM: To study the effect of artemether (Art) on glyceraldehyde-phosphate dehydrogenase (GAPDH), phosphoglycerate kinase (PGK), and pyruvate kinase (PK) of S japanicum. METHODS: Mice infected with schistosome cercariae for 32-38 d were treated ig with Art 100-300 mg.kg-1 and killed 24-72 h after medication for collection of schistosomes. The activities of GAPDH, PGK, and PK of the worms were determined by measuring the formation of NADH or consumption of NAD. The lactate content of the worms was also measured. RESULTS: After the infected mice were treated ig with Art 300 mg.kg-1 for 24 h, the inhibition rates of GAPDH were 13% (Male) and 21% (Female), and 48 h later the inhibition rates of the enzyme were 6% (Male) and 28% (Female). When Art 300 mg.kg-1 was given to infected mice for 24 h and 48 h, the inhibition rates of PGK were 60% (Male) and 48% (Female) as well as 75% (Male) and 62% (Female), respectively. Similar results were seen in PK activity. At 72 h after treatment the reduction rate of lactate content in Female worm was 72%, while that of Male was 48%. CONCLUSION: In the glycolytic pathway of both Male and Female schistosomes, PGK and PK activities were inhibited by Art. The GAPDH activity of Female worms was also susceptible to Art, While that of Male worms showed only temporary inhibition after treatment with Art. The Art reduced lactate content more in Female than in Male worms.


Subject(s)
Artemisinins , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Phosphoglycerate Kinase/metabolism , Pyruvate Kinase/metabolism , Schistosoma japonicum/enzymology , Schistosomicides/pharmacology , Sesquiterpenes/pharmacology , Animals , Artemether , Female , Lactic Acid/metabolism , Male , Mice , Schistosomiasis japonica/enzymology , Sex Factors
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