Esophagus ; Foreign Bodies ; Humans ; Infant ; Male

Actins ; analysis ; Animals ; Dimethylnitrosamine ; Immunohistochemistry ; Liver ; metabolism ; pathology ; Male ; Necrosis ; chemically induced ; pathology ; Rats ; Rats, Wistar ; Reticulin ; analysis ; Silver Staining

Objective To compare the infectivity between laboratory adapted human inununodefi- ciency virus(HIV-1) and primary HIV-1 isolates for different mucosal epithelial cell lines. Methods Mu-cosal epithelial cells Caco-2, T-84, HeLa and lymphocyte MT-4 were infected with laboratory adapted HIV-1 SF33 and 2 primary HIV-1 isolates (02010561, 02010141). Culture supernatant and cells were collected respectively on 3-4 days interval after virus inoculation. The former was tested for HIV-1 antigen P24 level and viral load, and the latter was tested for total viral DNA and integrated viral DNA. Results All 3 virus strains could infect MT-4 cells and integrate into their genome. Only HIV-1 SF33 could infect Caco-2 cells but could not integrate into their genomic DNA. Both HIV-1 SF33 and 02010561 infected HeLa cells but only integration of HIV-1 SF33 was detected. All the 3 HIV-1 strains infected T-84 cells but only the integra-tion of HIV-1 SF33 and 02010141 was observed. Conclusion Although laboratory adapted and primary HIV-1 strains are able to infect human mucosal epithelial cell lines, transient or productive infection estab-lished in different mucosal epithelial cells is dependent on the character of cells and virus strains.

Thienorphine is a chemically-new opioid developed in Beijing Institute of Pharmacology and Toxicology. To elucidate the chemical basis for the unique pharmacological effects of thienorphine, 15 derivatives were synthesized according to combinatorial chemistry and the structure-activity relationships of these compounds were studied. It is demonstrated that thienorphine is a potent long-acting partial agonist. N-Cyclopropylmethyl is responsible for the antagonist effect of thienorphine. More importantly, thiophene at the end of side chain is most likely the pharmacophore accounts for the long-lasting effect of thienorphine. Change of the connection of thiophene and the side chain does not result in changes in the antinociceptive activity.
Animals ; Buprenorphine ; analogs & derivatives ; pharmacokinetics ; pharmacology ; Combinatorial Chemistry Techniques ; Dose-Response Relationship, Drug ; Female ; Male ; Mice ; Mice, Inbred Strains ; Morphine ; pharmacology ; Rats ; Rats, Wistar ; Receptors, Opioid ; agonists ; Structure-Activity Relationship

OBJECTIVETo analyze the constituent proteins in donkey hide, the key ingredient for Ejiao, an important traditional Chinese medicine for the blood-related conditions, in hope to eventually decipher the biochemical mechanism behind Ejiao's prominent medicinal efficacy.

METHODTwo methods were employed to extract proteins in donkey skin. One used TriPure isolation reagent to extract the total proteins in donkey skin. Another used 1% sodium dodecyl sulfate (SDS) to heat the sample at 100 degrees C overnight. And then sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and capillary HPLC were used to analyze the component of proteins.

RESULTThere are not only collagen alpha1 (I) and collagen alpha2 (I), but also serum albumin in donkey skin. The content is over 25% in total proteins with the method of TriPure isolation reagent. The content of donkey serum albumin is up to 20% with the method of 1% SDS heating. And two bands, molecular weight are nearly 200 kDa,were found on 7.5% SDS-PAGE. Extracted these proteins to analyze with capillary HPLC, they were found to be the complex products of collagen and serum albumin of donkey.

CONCLUSIONDonkey serum albumin is a main protein component in the hide, which is a clue to expose is the effect of Ejiao on blood.

Animals ; Chromatography, High Pressure Liquid ; Collagen Type I ; analysis ; chemistry ; metabolism ; Collagen Type II ; analysis ; chemistry ; metabolism ; Drug Interactions ; Electrophoresis, Polyacrylamide Gel ; Equidae ; Molecular Weight ; Protein Binding ; Serum Albumin ; analysis ; chemistry ; metabolism ; Skin ; chemistry

OBJECTIVEThis study aimed at exploring the feasibility of using dried blood spots (DBS) to detect HIV drug resistance genotyping in China by comparing the results of drug resistance from DBS, plasma and whole blood samples.

METHODSBlood samples were collected from 39 AIDS patients from Anhui (10), Yunnan (13), Hunan (6) and Xinjiang (10) provinces and autonomous regions. The HIV strains that infected these patients covered all the major HIV-1 subtypes prevailing in China (B, CRF01_AE, CRF07_BC). HIV drug resistance genotyping assay was performed on DBS as well as on the whole blood and plasma samples from the same patients simultaneously by using an in-house nest RT-PCR method. Drug resistance levels were determined based on Stanford University HIV drug resistance database, and the results from these three types of samples were compared.

RESULTSThe percentages of successful amplification of protease and reverse transcriptase regions in the pol gene were 95% (37/39) from DBS, 92% (36/39) from whole blood and 100% (39/39) from plasma samples. The sequences from the three types of samples showed more than 99% identity.86% (31/36) of the DBS samples had the same set of drug resistance mutations as those which were detected from plasma samples. The differences probably resulted from mixed bases.

CONCLUSIONSThere was no major difference in detecting HIV drug resistance genotyping among DBS, plasma and whole blood samples. Therefore, DBS is useful for detection of HIV drug resistance genotyping and is particularly valuable in developing countries like China, especially in remote rural regions.

Dried Blood Spot Testing ; Drug Resistance, Viral ; genetics ; Feasibility Studies ; Genotype ; HIV Infections ; blood ; genetics ; virology ; HIV Seropositivity ; blood ; genetics ; virology ; HIV-1 ; drug effects ; genetics ; Humans ; Reverse Transcriptase Polymerase Chain Reaction ; Viral Load

Mammalian cells are prone to apoptosis when cultured in large scale for production of biopharmaceuticals. And this will reduce production duration and result in high cost of production. Apoptosis is triggered by various factors, and delicately regulated by a set of genes. Bcl-2, a component integrated in mitochondria membrane, is an important member of these genes. By maintaining the integrity of mitochondria membrane, Bcl-2 keeps cytochrome C from releasing into cytoplasm, and thus blocks the activation of caspases, and subsequent onset of apoptosis. Over-expression of Bcl-2 has proven to be useful in blocking apoptosis in various cell lines, including CHO, hybridoma, myeloma, lymphoma and insect cells. Ammonia, a metabolite of cultured cells, however, showed apparent pro-apoptosis activity. In living cells, ammonia can be utilized by glutamine synthetase (GS) to synthesize glutamine, and thus lower the concentration of ammonia in medium, and its negative effects. Glutamine is essential to living cells. If not added into medium, glutamine can only be synthesized by GS, which makes GS a qualified selection marker. This marker can be used for gene amplification by adding into medium increased concentration of MSX, an inhibitor of GS. In this study, we over-expressed Bcl-2 using GS amplification in a recombinant CHO cell line stably expressing human interferon-beta. The modified cell line, with higher expression of Bcl-2 and lower production of ammonia, exhibited good anti-apoptosis quality and higher interferon-beta production in continuous culture.
Animals ; Apoptosis ; genetics ; physiology ; Biopharmaceutics ; CHO Cells ; cytology ; metabolism ; Cricetinae ; Cricetulus ; Glutamate-Ammonia Ligase ; genetics ; metabolism ; Interferon-beta ; metabolism ; Models, Genetic ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism

Serum used widely in mammalian cell culture is also a potential source of bacterial, mycoplasmal and viral contaminations. In addition, the complex biological components in serum make harder the subsequent product recovery process. High cost, high batch variation and potential source limitation are among the other shortcomings. So serum-free or even protein-free medium are preferable for recombinant protein production. However, without serum to provide essential components such as hormones, growth factors and binding proteins, cells are easy to die. In this study, CHO-dhfr- cells were genetically engineered to make them adapted to IMEM, a protein-free medium, and resistant to apoptosis. The genes in choice are insulin-like factor (Igf-1), Bcl-2 and cyclin E. Bcl-2 is a mitochondrial membrane-integrated protein. It can block the release of cytochrome c by maintaining the integrity of mitochondrial membrane, and thus inhibit apoptosis. Igf-1 is similar both in structure and function to insulin, a growth factor added to serum-free medium to promote cell growth and is the only protein component in many currently used serum-free media. cyclin E is a cell cycle protein expressed continuously in G1 phase. When cyclin E accumulates to certain amount, cell cycle was driven to S phase. So cyclin E is a proliferation-promoting protein. By co-express Igf-1/Bcl-2 or Bcl-2/ cyclin E in CHO-dhfr- cells with a dicistronic expression vector, we constructed two cell lines: CHO-IB and CHO-BC. The high expression of each protein was confirmed by Western blot and flow cytometry. Apoptosis was analyzed by flow cytometry and DNA ladder detection, and the two cell lines were both found much more resistant to apoptosis induced by withdrawal of serum or addition of actinomycin D than the CHO-dhfr- parent cell. Cell proliferation assay by MTT method showed that the two cell lines proliferated much faster than CHO-dhfr- in IMDM medium without serum. Continuously culture assay proved that the two cell lines grow very well in IMEM protein-free medium supplemented with fibronectin and vitronectin to ease adherence. When compared to CHO-dhfr-, the two cell lines exhibited much more viable cell numbers and faster growth rate.
Animals ; Apoptosis ; CHO Cells ; Cloning, Molecular ; Cricetinae ; Cricetulus ; Culture Media ; Cyclin E ; genetics ; Genes, bcl-2 ; Insulin-Like Growth Factor I ; genetics

OBJECTIVETo evaluate the protective effect of N-acetylcysteine (NAC) on the intestinal barrier dysfunction in rats after extensive abdominal radiation with X ray.

METHODSTwenty-four Spraque-Dawley male rats were divided into normal control group (n=8), radiation group (n=8), and radiation+NAC group (300 mg/kg) (n=8). Radiation injury was induced by X ray with a single dose of 10 Gy. NAC was administered from 4 days before irradiation to 3 days after radiation. Three days after radiation, all the rats were euthanized. The terminal ileum was collected for crypt survival assay and ileal villi count. The tissue samples from mesenteric lymph nodes (MLN), spleen, and liver were harvested under sterile conditions for microbiological analysis and ileum samples were harvested for biochemical analysis. The blood levels of D-lactate, endotoxin and diamine oxidase (DAO) and the ileum samples levels of nitric oxide(NO) were also measured.

RESULTSRats in radiation+NAC group had a higher survival rate of intestinal crypt [(76.84+/-4.82)% vs (49.64+/-5.48)%, P<0.01], higher intestinal villus count [(8.56+/-0.68)/mm vs (4.02+/-0.54)/mm, P<0.01], lower NO concentration [(0.48+/-0.12) mumol/g vs (0.88+/-0.16) mumol/g, P<0.01], lower levels of D-lactate, endotoxin and DAO (P<0.05 or P<0.01), and significantly decreased enteric bacteria cultured from mesenteric lymph nodes and other tissues as compared with the radiation group (P<0.05 or P<0.01).

CONCLUSIONNAC protects the small intestine from radiation-induced injury maybe through the inhibition of NO in rats.

Acetylcysteine ; pharmacology ; Animals ; Dose-Response Relationship, Radiation ; Intestinal Mucosa ; drug effects ; metabolism ; microbiology ; Intestine, Small ; drug effects ; Male ; Nitric Oxide ; analysis ; Radiation Injuries ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley ; X-Rays ; adverse effects

Without serum to provide adherent factors, CHO-dhfr- cells grow in suspension when cultured in serum-free medium. Although this offers advantages in some applications, in most production systems adherent cell growth is preferable. Gene transfection, clonal selection and amplification can be easier for adherent cells; the density of immobilized cells is often higher than those in suspension culture, which results in a higher protein productivity; washout of cells by perfused medium during continuous fermentation can be avoided; for high-throughput microplate assays, adherent cells are preferred to facilitate medium changes and cell washing. It has been proved that purified vitronectin alone was able to mediate attachment and spreading of CHO cells in serum-free medium. So we constructed a tricistronic expression vector expressing Igf-1, Vitronectin and Bel-2 at the same time. The vector was transfected into CHO-dhfr- cells and one clone, namely CHO-IVB2, expressing high level of the three proteins was screened out by Western blot. The cell line showed similar apoptosis-resistant and serum-independent properties to CHO-IB, an engineered cell line constructed before. When cultured in IMEM protein-free medium without any components supplemented, CHO-IVB can grow adherently. The viable cell numbers and growth rate of CHO-IVB were much higher than CHO-IB, making CHO-IVB an apoptosis-resistant host for production of recombinant proteins which can grow adherently in protein-free medium.
Animals ; Apoptosis ; CHO Cells ; physiology ; Cell Adhesion ; Cell Line ; Cell Proliferation ; Cricetinae ; Cricetulus ; Culture Media, Serum-Free ; Flow Cytometry ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; biosynthesis ; Vitronectin ; genetics