[The pharmacognostical identification of peel of Gymnema sylvestre].
This paper reported the descriptions, microscopic UV and TLC identification of peel of Gymnema sylvestre.
Apocynaceae↗
Biomedical subjects
X Pan
Publications and source records attributed to X Pan.
[Detection of gangliosides in human milk with a high performance thin layer chromatography (HPTLC)].
OBJECTIVES: To determine the ganglioside composition in human milk during lactation, and to evaluate the biological significance. METHODS: The gangliosides extracted from 68 milk samples were examined with a high performance thin layer chromatography (HPTLC). RESULTS: The concentration of total lipid bound sialic acid was 7.8-10.4 microliters/ml. Four gangliosides were found and designated as GM3, GD3, GX1 and GX2, respectively. GX1 and GX2, which had not been described previously, were tentatively assumed to be gangliosides of the c-pathway because they did not react to the GA1 antibody after sialidase treatment. GD3 and GM3 were the major gangliosides in human milk (accounted for 50%-65%). CM3 decreased sharply at eight days postpartum. Both GM3 and GD3 changed significantly during lactation (GM3, r = 0.65, P < 0.01; GD3, r = -0.58, P < 0.01). CONCLUSIONS: Four gangliosides, GM3, GD3, GX1 and GX2 were found in human milk. Both GM3 and GD3 changed significantly during lactation.
Adult↗
[The effect of EB virus bhrfl gene expressing on the topoisomerase I expression in nasopharyngeal carcinoma cell line].
OBJECTIVE: To study the effect of bhrfl expressing on the topoisomerase I expression in nasopharyngeal carcinoma cell line CNE2. METHODS: bhrfl recombinant expressing vector was constructed and used to transfect the nasopharyngeal carcinoma cell line CNE2. The CNE2 cells were then tested for changes of the topoisomerase I expression and anti-apoptotic ability under the treatment of camptothecin. RESULTS: bhrfl expressing could enhance the topoisomerase I expression in CNE2 cells, that in end reduced cell sensitivity to camptothecin increased cell survival span and decreased apoptotic rate(P < 0.01). CONCLUSION: By increasing the expression of topoisomerase I, bhrfl expressing can enhance the resistance of CNE2 cells to apoptosis induced by camptothecin.
Antineoplastic Agents, Phytogenic↗
[UV photolysis mechanism of CCl4 and CHCl3 in water].
The photolysis mechanism of CCl4 and CHCl3 in water was studied by using transient absorption spectra. The results showed that aqueous CCl4 was dissociated into CCl3 and Cl radicals by 248 nm laser, and CHCl3 was dissociated into CHCl2 and Cl radicals after adding C6H6. The radicals CCl3 and CHCl2 were able to react with O2 to form CCl3O2 and CHCl2O2 respectively, or to form C2Cl6 and C2H2Cl4 without O2. The rate coefficients of some reactions were obtained.
Carbon Tetrachloride↗
[The role of beta3-adrenergic receptor Trp/Arg mutation in childhood obesity].
OBJECTIVE: To understand with greater clearness the role of beta3- adrenergic receptor Trp/Arg mutation in childhood obesity. METHODS: One hundred and seventy-seven children, aged 6-12 years, were selected. The genotype was detected by restricted fragment length polymorphism, the children's dietaries were surveyed by a 3-day recalling and recording method. Their height, weight were measured, and the data on their living habits were collected from their parents. RESULTS: The intake of total amount of food and energy of obese children were higher in children with Trp/Trp genotype, but there was no difference between the obese and non-obese children with Trp/Arg genotype. Among children with the Trp/Arg genotype, obese children were less active and did less exercise, they slept more, but there was no difference among children with Trp/Trp genotype. CONCLUSION: The children with beta3-AR Trp/Arg mutation may become obese because of the low energy metabolism; less active and exercise may increase the risk of obesity.
Child↗
[The Immunophenotypical features of t (8; 21) (q22; q22) acute myeloid leukemia].
OBJECTIVE: To study the predictive value of immunophenotypical features in t (8; 21) (q22; q22) acute myeloid leukemia (AML). METHODS: Morphological/cytochemical, flow cytometric immunophenotyping, cytogenetic analyses (MIC) and RT-PCR were performed in 294 previously untreated AML. RESULTS: (1) In 294 AML patients, t (8; 21) AML were 21.8% (64); in AML-M(2), t (8; 21) AML were 54.7%; and in t (8; 21) AML, AML-M(2) were 81.3%. (2) Compared with control group, CD(19) and CD(34) expressions were higher, and CD(33) expression was lower (P < 0.001) in t (8; 21) AML. (3) If the cut-off value of CD(19) positive was >or= 20%, CD(19) positive rate was 13.6% (40/294) in AML, and 50% (32/64) and 3.5% (8/230) (P < 0.001) in t (8; 21) AML and control group. (4) CD(19)(+) and/or CD(34)(+) t (8; 21) AML accounted for 90.6% (58/64) of t (8; 21) AML and CD(19)(-)/CD(34)(-) for 9.6% (6/64). CONCLUSION: In t (8; 21) AML, especially M(2)/t (8; 21), CD(19) and CD(34) expressions were high. CD(19) was one of predictive markers of t (8; 21) AML.
Adolescent↗
[Detection of TT virus DNA and sequence analysis of TTV gene in sera from young children in Nanjing].
OBJECTIVE: To investigate the prevalence of TTV genomes in young children from Nanjing and establish the PCR method for detecting TTV DNA. METHODS: A hemi-nested polymerase chain reaction (PCR) assay was established to detect TTV DNA in 110 young children and two PCR-amplified products were sequenced and the data were analyzed with the computer programs. RESULTS: TTV DNA was detected in 14 out of 110 children, and 222 bp sequences of 2 isolates from the children were analyzed. Compared with representative of published isolates, they have the nucleotide identity of 93.7%-98.6% with TX011. CONCLUSIONS: The infection rate of TTV in children is 12.73%, and 2 isolates from children belong to subgroup G1b. Our results indicates that TTV could be transmitted via other pathway besides hematogenous one, and TTV could be carried by healthy population.
Base Sequence↗
[Clinical application of Targis veneers].
OBJECTIVE: The aim of this study was to evaluate the Targis material in the form of veneers. METHODS: Nineteen patients treated with 91 Targis veneers were involved in this study, and the clinical evaluation on veneers was conducted at the time of recall. The evaluation parameters included marginal adaptation, marginal discoloration, surface texture and color match. The periodontal status of all teeth with veneers was evaluated by gingival bleeding index and plaque index before and after the treatment. RESULTS: The mean observation period for the veneers was 14.6 months. Four veneers failed due to fracture, three because of debond, one because of discoloration. The cumulative rate of success was 91.2%. There was no significant difference in gingival bleeding index before and after treatment, but the plaque index significantly decreased after the treatment. CONCLUSION: The clinical results of Targis are satisfactory.
Adult↗
[Clinical studies on sternocleidomastoid myoperiosteal flap for cervical tracheal reconstruction].
OBJECTIVE: To introduce the experience of repairing the defect of cervical trachea wall by using the sternocleidomastoid myoperiosteal flap after the anterior or posterior wall of cervical trachea was invaded by cervical neoplasm. METHOD: Between 1989 to 1998 the sternocleidomastoid myoperiosteal flap was applied in 12 patients with different diseases, among which 3 cases were thyroid carcinoma 5 cases were laryngeal carcinoma, 4 cases were cervical esophageal carcinoma. RESULT: The operation was successful. 12 patients were decannuated and had normal exercise tolerance. The time from reconstruction to decannulation was ranging from 20 days to 6 months. CONCLUSION: The sternocleidomastoid myoperiosteal flap is an ideal transplant for cervical tracheal reconstruction.
Adolescent↗
[Measurement of microvessel density in laryngeal carcinoma and its clinical significance].
OBJECTIVE: To determine the microvessel density (MVD) in laryngeal carcinoma and its clinical significance. METHOD: Thirty-eight tumor specimens were selected from laryngeal cancer patients from January, 1994 to March, 1996. Histological sections of the tumors were stained immunohistochemically for factor VIII. Using light microscopy, we counted microvessels per 400 x field in the most active areas of tumor angiogenesis. RESULT: 1. The tumor blood vessels, composed of only one layer of endothelium were mainly distributed heterogeneously in the interstitial tissue of laryngeal carcinoma with irregular lumen, poorly developed structure. 2. The MVD in the cancer tissues were statistically higher than that in peritumoral tissues (P < 0.01). 3. The MVD in the cancer tissues in group of patients with metastasis to cervical lymphonodes were statistically higher than in group without metastasis (P < 0.01), the MVD in the cancer tissues in group of advanced cases (III, IV stages) were statistically higher than that in group of early cases (I, II stages, P < 0.01). 4. There was no statistically difference in MVD in the cancer tissue between supraglottic and glottic laryngeal carcinoma patients (P > 0.05). 5. There was no statistically difference in MVD in the cancer tissue among the G1, G2 and G3 group (P > 0.05). CONCLUSION: The laryngeal cancer blood vessels have some characteristics that don't appear in normal vessels. It is suggested that tumor angiogenesis can promote tumor growth and metastasis and MVD may be a new prognostic indicator of laryngeal carcinoma.
Adult↗
[Surgical management of subglottic carcinoma].
OBJECTIVE: To explore the surgical management and evaluate the effect on patients with subglottic cancer. METHODS: Fourteen cases with subglottic carcinoma were treated surgically from 1989 to 1998. There were T1-2N0 lesions in 5 cases, T3N0-2 lesions in 3 cases and T4N0-1 lesions in 6 cases. Eleven cases underwent partial laryngectomy and three cases underwent total laryngectomy. The defects of larynx were reconstructed by using uni-pedicled or bi-pedicled stemohyoid myofascial flap, platysma myocutaneous flap, sternocleidomastoid myoperiosteal flap, thyroid perichondral flap and epiglottis flap accordingly. Unilateral neck dissection was performed on 4 cases and bilateral on one. RESULTS: The function of phonation had been restored in all cases except in 3 patients who underwent total laryngectomy. Seven out eleven(63.6%) were decannulated. The swallowing function was restored in all patients. In all cases the 3 and 5 year survival rates were 78.6%(11/14) and 63.6% (7/11), respectively. CONCLUSIONS: The conservative surgery can be used for the majority of the subglottic carcinoma if the lesions were entirely resected. The proficiency in surgical methods is crucial for the preservation of laryngeal function.
Adult↗
[Preservative surgery of medial wall pyriform sinus cancer].
OBJECTIVE: To study the surgical methods and functional outcome of preservative surgery for medial wall pyriform sinus cancer. METHODS: Seventy-one patients with medial wall pyriform sinus cancer, who were treated surgically between 1985 and 1997, were reviewed. Of the 71 cases, 49 underwent preservative surgery, and 22 total laryngectomy. Preservative surgical procedure was defined as follows: 1. Extent of resection: Supraglottic horizontal partial laryngectomy and resection of medial wall of pyriform sinus were performed in patients without fixation of the true vocal cord, and the section extended to paraglottic space, partial lateral wall of pyriform sinus, preepigottic space, superior-posterior of thyroid cartilage in those with restrained vocal cord motility. Supracricoid hemilaryngopharyngectomy and resection of medical wall and partial lateral wall of pyriform sinus were practiced in those with fixed hemilarynx. Cricoid ring and cervical esophagus were removed partially if the pyriform sinus apex was involved. 2. Reconstruction: Larynx: the remains of epiglottis, perichondrium of thyroid cartilage, the infrahyoid muscular fascia, and the platysmal flap were utilized to restore the defects of larynx. Pyriform sinus: Suturing the remaining pharyngeal mucosa directly to cover the wound if the defect was relatively small. For the large defect produced by extended resections, the pectoralis major myocutaneous flap and deltopectoral flap were used. 3. Surgical treatment of cervical lymphaden: Sixty five out of the 71 cases (91.5%) underwent neck dissection. Of which ipsilateral neck dissection were done in 39 cases, and bilateral neck dissection in 26 cases. 4. All patients received postoperative radiotherapy with doses of 60-75 Gy. RESULTS: In the group of preservative surgery the 3- and 5-year survival rates were 63.4% and 49.6% respectively, whereas those in the total laryngectomy group were 52.4% and 42.4% respectively. Of the 49 cases with preservative surgery, 71.4% (35/49) had all laryngeal functions restored and 28.6% (14/49) partially restored. CONCLUSION: Despite the fact that the medial wall pyriform sinus cancer tends to have laryngeal invasion, preservative surgery can be practiced for the majority of the cases with the lesions entirely removed.
Adult↗
The roles of mutS, sbcCD and recA in the propagation of TGG repeats in Escherichia coli.
A 24 triplet TGG.CCA repeat array shows length- and orientation-dependent propagation when present in the plasmid pUC18. When TGG(24) is present as template for leading-strand synthesis, plasmid recovery is normal in all strains tested. However, when it acts as template for lagging-strand synthesis, plasmid propagation is seriously compromised. Plasmids carrying deletions in the 5' side of this sequence can be isolated and products carrying 15 TGG triplets do not significantly interfere with plasmid propagation. Mutations in sbcCD, mutS and recA significantly improve the recovery of plasmids with TGG(24) on the lagging-strand template. These findings suggest that TGG(24) can fold into a structure that can interfere with DNA replication in vivo but that TGG(15) cannot. Furthermore, since the presence of the MutS and SbcCD proteins are required for propagation interference, it is likely that stabilisation of mismatched base pairs and secondary structure cleavage are implicated. In contrast, there is no correlation of triplet repeat expansion and deletion instability with predicted DNA folding. These results argue for a dissociation of the factors affecting DNA fragility from those affecting trinucleotide repeat expansion-contraction instability.
Adenosine Triphosphatases↗
Interaction of H2 with Si(001)-(2 x 1): solution of the barrier puzzle.
The sticking probability of H2 on Si(001) is immeasurably small at room temperature, indicating the presence of a large energy barrier to adsorption. Surprisingly, the final state energy distributions of H2 molecules desorbing from Si(001) show no signs of having traversed such a barrier, in apparent contradiction with microscopic reversibility. Here we report experimental and theoretical evidence resolving this long-standing puzzle. Adsorption and desorption proceeding along two distinct, microscopically reversible pathways can explain all observations.
Journal Article↗
Microwave-assisted extraction of glycyrrhizic acid from licorice root.
In the present study, a microwave-assisted extraction (MAE) technique has been developed for the extraction of glycyrrhizic acid (GA) from licorice root. Various experimental conditions, such as extraction time, different ethanol and ammonia concentration, liquid/solid ratios, pre-leaching time before MAE and material size for the MAE procedure were investigated to optimize the efficiency of the extraction. Under appropriate MAE conditions, such as extraction times of 4-5min, ethanol concentrations of 50-60% (v/v), ammonia concentrations of 1-2% (v/v) and liquid/solid ratios of 10:1(ml/g), the recovery of GA from licorice root with MAE was equivalent with conventional extraction methods. Those methods include extraction at room temperature (ERT), the traditional Soxhlet extraction, heat reflux extraction and ultrasonic extraction. Due to the considerable savings in time and solvent, MAE was more effective than the conventional methods. This novel method is suitable for fast extraction of GA from licorice root.
Journal Article↗
Pleiotropic resistance to diverse antimalarials in actinomycin D-resistant Plasmodium falciparum.
The development and spread of multidrug-resistant Plasmodium falciparum are major health concerns. The molecular mechanisms of multidrug resistance, including resistance to many quinoline-based antimalarials, are largely unknown. In this study, we report on the isolation and partial characterization of actinomycin D (actD)-resistant P. falciparum (3D7(R)/actD2.3) from a chloroquine-susceptible strain, 3D7. The stepwise selection of an actD-resistant clone (3D7(R)/actD2.3) led to the isolation and cloning of P. falciparum that grew in the presence of 2 ng/mL of actD. The parental isolate (3D7) did not grow in the presence of a 10-fold lower drug concentration (0.2 ng/mL). The latter estimate of parasite growth was determined by direct counting of parasites in infected red blood cells. Estimates of drug resistance levels to actD, using a [(3)H]hypoxanthine uptake and incorporation method, showed a 3-fold difference in the IC(50) between 3D7 and 3D7(R)/actD2.3. Interestingly, 3D7(R)/actD2.3 P. falciparum parasites were less sensitive to several antimalarials (chloroquine, mefloquine, quinidine, and artemisinin) and to the mitochondrial specific dye Rhodamine 123. Drug transport studies using [(3)H]actD showed that 3D7(R)/actD2.3 accumulated less drug than 3D7. Moreover, the accumulation of [(3)H]actD was energy dependent. To determine if Pfmdr1 expression, previously implicated in drug resistance to certain antimalarials, mediated the resistance phenotype of 3D7(R)/actD2.3, Pfmdr1 levels in 3D7 and 3D7(R)/actD2.3 were compared by Southern and northern blot analyses. Our results revealed no differences in Pfmdr1 copy number or mRNA levels between 3D7 and 3D7(R)/actD2.3. Furthermore, comparison of Pfmdr1 sequences between 3D7 and 3D7(R)/actD2.3 showed no differences. In addition, verapamil, which reverses P-glycoprotein-mediated drug resistance in mammalian cells, did not reverse the resistance of 3D7(R)/actD2.3 to actD or chloroquine. Taken together, the findings of this study demonstrated that in vitro selection of P. falciparum for resistance to actD leads to decreased sensitivity to diverse drugs and that this pleiotropic drug resistance is associated with reduced drug accumulation not mediated by Pfmdr1.
ATP Binding Cassette Transporter, Subfamily B, Mem↗
NMR structure of activated CheY.
The CheY protein is the response regulator in bacterial chemotaxis. Phosphorylation of a conserved aspartyl residue induces structural changes that convert the protein from an inactive to an active state. The short half-life of the aspartyl-phosphate has precluded detailed structural analysis of the active protein. Persistent activation of Escherichia coli CheY was achieved by complexation with beryllofluoride (BeF(3)(-)) and the structure determined by NMR spectroscopy to a backbone r.m.s.d. of 0.58(+/-0.08) A. Formation of a hydrogen bond between the Thr87 OH group and an active site acceptor, presumably Asp57.BeF(3)(-), stabilizes a coupled rearrangement of highly conserved residues, Thr87 and Tyr106, along with displacement of beta4 and H4, to yield the active state. The coupled rearrangement may be a more general mechanism for activation of receiver domains.
Amino Acid Sequence↗
Inhibition of xanthine oxidase by liquiritigenin and isoliquiritigenin isolated from Sinofranchetia chinensis.
The methanol extract of the stem of Sinofranchetia inhibited the activity of xanthine oxidase in vitro. Bioassay-guided purification led to the isolation ofliquiritigenin and isoliquiritigenin as the main xanthine oxidase inhibitors. This inhibition of enzyme activity was found to be dose dependent, with an IC50 value of approximately 49.3 microM for liquiritigenin and 55.8 microM for isoliquiritigenin. Lineweaver-Burk transformation of the inhibition data indicated that the inhibition was of a mixed type for both liquiritigenin and isoliquiritigenin. For liquiritigenin, the Ki and K(I) were determined to be 14.0 microM and 151.6 microM, respectively. For isoliquiritigenin, the Ki and K(I) were determined to be 17.4 microM and 81.9 microM, respectively. These results suggest that these natural products could be used to treat conditions where the inhibition of xanthine oxidase is warranted.
Animals↗