Screening and detection of antimicrobials from Dai pharmaceuticals against clinical diseases by methicillin-resistant Staphylococcus aureus.

Oroxylum indicum is one of the valuable Dai pharmaceuticals; the dry seeds and bark of O. indicum were used to treat acute cough, sore throat and so on. Of the seven compounds from O. indicum were determined and obtained using the bioassay-guided method. Among them, compound 7 was obtained from the plant for the first time. Eight bacterial strains and one yeast fungi were exposed to the compounds. Minimum inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) or minimum fungicidal concentrations were determined according to the standard broth microdilution method. Baicalein (2) exhibited relative strong antibacterial activities with MIC of 8 µg ml-1 and MBC of 16 µg ml-1 against three MRSA strains of Staphylococcus aureus of SCCmec III type, whereas flavonoids 3, 5 and 7 showed some degree of activities against methicillin-susceptible S. aureus (MSSA, ATCC 25923). The findings may offer new evidence that why O. indicum was used widely in Dai peoples' life.

Growth and laser properties of Nd3+-doped Bi4Ge3O12 single-crystal fiber.

The Nd3+-doped Bi4Ge3O12 (BGO) single-crystal fiber (SCF) was successfully grown by the micro-pulling-down method with the resistance heating system. The fluorescence spectrum and transmission spectrum of the Nd:BGO SCF were measured. Excited by a continuous-wave 808-nm laser diode, a fluorescence peak around 1064 nm was observed. At an absorbed pump power of 15.25 W, the Nd:BGO SCF laser delivered a power of 3.37 W with a slope efficiency of 31.2%.

Molecular cloning and developmental expression of the vitellogenin gene in the endoparasitoid, Pteromalus puparum.

A cDNA of the vitellogenin (Vg) protein gene was isolated from the endoparasitoid Pteromalus puparum and characterized. The putative coding sequence was found to be 5634 bp long, encoding 1803 amino acids in a single open reading frame. The chemically determined N-terminal amino acid sequence of vitellin completely matched the deduced amino acid sequence that follows a putative signal peptide of 17 amino acid residues. The Vg mRNA was detected in the fat body of late female pupae, whereas the ovary and male fat body lacked the Vg transcript. The Vg mRNA level in the fat body depended significantly on the developmental stage, reaching the highest level 0 h after eclosion. The haemolymph Vg titre appeared 24 h after the appearance of Vg transcript. A positive correlation between the titre and transcript level of Vg in individual female wasps was found.

Honeybee (Apis cerana) foraging responses to the toxic honey of Tripterygium hypoglaucum (Celastraceae): changing threshold of nectar acceptability.

To investigate honeybee foraging responses to toxic nectar, honey was collected from Apis cerana colonies in the Yaoan county of Yunnan Province, China, during June, when flowers of Tripterygium hypoglaucum were the main nectar source available. Pollen analysis confirmed the origin of the honey, and high-performance liquid chromatography showed the prominent component triptolide to be present at a concentration of 0.61 mug/g +/- 0.11 SD. In cage tests that used young adult worker bees, significantly more of those provided with a diet of T. hypoglaucum honey mixed with sugar powder (1:1) died within 6 d (68.3%) compared to control groups provided with normal honey mixed with sugar powder (15.8%). Honeybees were trained to visit feeders that contained honey of T. hypoglaucum (toxic honey) as the test group and honey of Vicia sativa or Elsholtzia ciliata as control groups (all honeys diluted 1:3 with water). Bees preferred the feeders with normal honey to those with toxic honey, as shown by significantly higher visiting frequencies and longer imbibition times. However, when the feeder of normal honey was removed, leaving only honey of T. hypoglaucum, the foraging bees returned to the toxic honey after a few seconds of hesitation, and both visiting frequency and imbibition time increased to values previously recorded for normal honey. Toxic honey thus became acceptable to the bees in the absence of other nectar sources.

Protein tyrosine phosphatase interacting protein 51 (PTPIP51) is a novel mitochondria protein with an N-terminal mitochondrial targeting sequence and induces apoptosis.

Apoptosis is a genetically determined cell suicide program. Mitochondria play a central role in this process and various molecules have been shown to regulate apoptosis in this organelle. In the present study, we firstly identified that protein tyrosine phosphatase interacting protein 51 (PTPIP51) is a novel mitochondrial protein, which may induce apoptosis in HEK293T and HeLa cell lines. PTPIP51 transfection resulted in the externalization of phosphatidylserine (PS), activation of caspase-3, cleavage of PARP, and condensation of nuclear DNA. Further investigation revealed that PTPIP51 over-expression caused a decrease in mitochondrial membrane potential and release of cytochrome c, suggesting that it may be involved in a mitochondria/cytochrome c mediated apoptosis pathway. We also found that a putative TM domain near the N terminus of PTPIP51 is required for its targeting to mitochondria, as evidenced by the finding that deletion of the PTPIP51 TM domain prevented the protein's mitochondiral localization. Furthermore, this deletion significantly influenced the ability of PTPIP51 to induce apoptosis. Taken together, the results of the present study suggest that PTPIP51 is a mitochondrial protein with apoptosis-inducing function and that the N-terminal TM domain is required for both the correct targeting of the protein to mitochondria and its apoptotic functions.

[Stimulatory effect of chemokine-like factor 1 (CKLF1) on the growth of bone marrow cells].

OBJECTIVE: To investigate the activity of CKLF1 on the proliferation and differentiation of bone marrow cells. METHODS: Human low density bone marrow cells and mouse bone marrow cells were plated in 96-well microplate and supernatants from transfected COS-7 cell culture were added. The cell proliferation was assayed by MTT method after 5 days incubation. The enhancing effect of CKLF1 on the colony formation of human hematopoietic progenitor cells was identified in semi-solid culture. RESULTS: CKLF1 has obvious enhancing effect on both human and mouse bone marrow cells, it can stimulate the colony formation of human hematopoietic stem cells and has synergistic action with GM-CSF. CONCLUSION: CKLF1 can promote the proliferation and differentiation of bone marrow cells.

[Eukaryotic expression and in vitro tumor cell apoptosis-induced effect of human TRAIL].

OBJECTIVE: To explore the tumor cell apoptosis induced by the effect in vitro of eukaryotic expression of full-length TRAIL cDNA and its extracellular region. METHODS: The eukaryotic expression vectors for both forms of the cDNA acquired from the fetal heart cDNA library were constructed. After gene transfecting, the stable expression cell lines were obtained by G418 screening. RESULTS: The supernatants from tansfectants could induce apoptosis of different tumor cell lines in vitro, and an enhanced effect was observed by adding TFAR19 (TF-1 cell apoptosis-related protein 19), a novel apoptosis gene product discovered in our laboratory. CONCLUSION: Eukaryotic expression products of TRAIL can induce apoptosis of the tumor cells, and TFAR19 could enhance the effect on apoptosis of tumor cells.

[Helicobacter pylori in the dental plaque].

Helicobacter pylori (Hp) were detected in the dental plaque in 40 patients with peptic ulcer, chronic gastritis or gastric cancer with rapid urease test, anti-Hp fluorescein-labelled antibody staining, bacterial culture and electronic microscopy. At the same time, biopsy specimens from the gastric antrum of these patients were studied with WS staining and rapid urease test to detect Hp. The results show that a great lot of Hps is present in most of the patients' dental plaque. The morphological, biochemical and immunological characteristics of the Hp in the dental plaque are similar to those Hp in the gastric mucosa. The above results reveal that the Hp in the dental plaque may be identical with those in the stomach.

Pharmacokinetics and tissue distribution of human recombinant interleukin-2 in mice.

125I-labeled human recombinant interleukin-2 (125I-rIL-2) was prepared by iodogen method with rIL-2 and Na125I. Product was purified by Sephacryl S-200 gel filtration. Eluate fractions were identified by SDS-PAGE and compared with standard rIL-2. Radioactive 95% purified 125I-rIL-2 fractions were selected for pharmacokinetic study, with a specific activity of 56 PBq.mol-1. Concentration-time curves after iv 75, 530, 603, and 6767 ng of 125I-rIL-2/mouse were fitted to a 3-compartment model: with a fast distribution phase T1/2 of 2 min, a slow distribution phase T1/2 of 30-120 min, and a terminal elimination T1/2 of 6-15 h. AUC was linearly related to the dosage (r = 0.9998). Systematic clearances were independent of the dosages. SDS-PAGE of plasma and urine samples showed that radioactivities due to 125I-rIL-2 were 81 +/- 13% (n = 16) and 91 +/- 8% (n = 3, at 4 h), respectively. Levels of 125I-rIL-2 after im were lower than those after i.v., with bioavailability of 0.57. Time to peak concentration was about 1.1 h. The highest levels were seen at 15 min after i.v. in liver, bile and kidneys, the concentration gradients were blood > adrenals > plasma > lungs > thyroid > spleen > jejunum > mesenteric lymph nodes > jejunum contents > ovaries > heart > bladder > thymus > feces in colon > thigh skeletal muscle > testes > brain > fat. Peak concentration time in most tissues were found at 15 min, but at 4 h in the feces.(ABSTRACT TRUNCATED AT 250 WORDS)

Differentiation of Anopheles gambiae and An. arabiensis (Diptera: Culicidae) by ELISA using immunoaffinity-purified antibodies to vitellogenin.

Yolk proteins (vitellogenin and vitellin) proved to be excellent marker molecules for separating Anopheles gambiae Giles and An. arabiensis Patton, two morphologically indistinguishable members of the An. gambiae species complex. A rabbit polyclonal antibody directed against An. gambiae yolk proteins was made species-specific by removing immunoglobulins that crossreacted with An. arabiensis by immunoaffinity chromatography. The resultant antibody was 400 times more sensitive to An. gambiae and was employed as the secondary antibody in a modified double antibody "sandwich" ELISA, which also used monoclonal antibodies to anopheline vitellogenin as the primary or coating antibody. This ELISA easily differentiated soluble yolk protein samples from An. gambiae and An. arabiensis. A field study with 628 females of An. gambiae complex collected in western Kenya demonstrated that the ELISA results were 98.4% in agreement with the standard cytotaxonomic method.