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Biomedical subjects

S Bai

Publications and source records attributed to S Bai.

At least 55 records · Page 3Linked to original sources

[Study on the reversal of cancer multidrug resistance by Chinese medicine Fw13-te41 in nude mice].

We have reported that three reversal agents were sifted out from 32 Chinese galenicals through a series of cell culture tests. Among them, Fw13-te41 has the best effect of reversal cancer multidrug resistance (MDR) in vitro. In this study, the reversal action of Fw13-te41 in vivo was studied on the animal model of nude mice with human leukemia k562/ADR. Twenty SPF BALB/c-nu/nu nude mice with xenograft tumor were randomly divided into the control group (n = 6), VCR group [intraperitoneal (i.p.) VCR 250 micrograms/week, n = 5], VCR + Fw13-te41 group (i.p VCR 250 micrograms/week + Fw13-te41 0.2 ml/day, equivalent to crude drug 10 g/kg, n = 5), and Fw13-te41 group (i.p Fw13-te41 0.2 ml/day, equivalent to crude drug 10 g/kg, n = 4). After 18 days, the rate of tumor inhibition (RTI) of VCR group was 19.79%, but the RTI of VCR + Fw13-te41 group was as high as 86.95% (P < 0.05). There results demonstrate that the Chinese medicine Fw13-te41 has an evident reversal action of malignancy MDR in vitro and in vivo.

Animals↗

[Clinicopathological characteristics and surgical treatment of primary neurogenic tumors of the mediastinum].

OBJECTIVE: To study the clinical and histopathological characteristics, and surgical treatment of primary neurogenic tumors of the mediastinum. METHODS: The experience in diagnosis and treatment of 125 patients with primary neurogenic tumors of the mediastinum from Jan. 1965 to Dec. 1998 in our hospital was summarized. All patients were operated and pathologically confirmed. RESULTS: Primary neurogenic tumor accounted for 125(22.0%) of 568 patients with primary tumors of the mediastinum in the same period. The incidence of neurilemoma was 48.9% (61/125), neurofibroma 27.2% (34/125), ganglioneuroma 13.6% (17/125), and other rare tumors 10.4% (13/125, neurofibrosarcoma 4, ganglioneuroblastoma 3, chemodectoma 3, pheochromocytoma 2, and neuroblastoma 1). In this series, 78 patients did not have any subjective symptoms, and the tumors were found on routine physical checkup. In 117 patients, the tumors were located in the posterior mediastinum. In all bwt 2 patients, the tumor was resectable. The postoperative complication rate was 4.0% and operative mortality rate was 0.8%. The 3-year survival rate in patients with malignant tumors was 18.2%. CONCLUSION: The clinical characteristics and prognosis of primary neurogenic mediastinal tumors varies with their histopathology. Surgical operation is the first choice of treatment.

Adolescent↗

[Establishment of a heterologous graft model for human breast infiltrating duct carcinoma in nude mice].

A heterologous graft model for human breast infiltrating duct carcinoma is reported in this paper. The grafts derived from an infiltration duct carcinoma of a patient's right breast and her metastatic lymphnode mass were transplanted into the breast pads of nude mice in 1996, and the carcinoma masses were found in breast pads 31 days later. By now, the grafts of carcinoma have been transplanted into nude mice for 15 passages with a full success in 59 mice and with the biological characteristics of the original breast carcinoma. This heterologous graft model was established for the first time in China and the results suggest it be a good model for further research of breast carcinoma.

Animals↗

[Random amplified polymorphic DNA analysis on Curcuma wenuujin and C. sichuanensis].

OBJECTIVE: To discuss the problem of classifying Curcuma for Medical purposes. METHOD: RAPD was used to detect the DNA polymorphism within and among Curcuma wenyujin, C. sichuanensis and C. aromatica. RESULT: It is hard to differentiate between C. wenyujin and C. sichuanensis from the DNA level. The relationship between C. wenyujin and C. aromatica was also analyzed. CONCLUSION: Based on the morphological and chemical data, it is suggested that these two species should be combined into one and that classification based on peduncle central or peduncle lateral may not be right. This method will help to some degree to solve the problem of certifying the medicinal plant Curcuma.

Curcuma↗

[Association of VNTR region of the human serotonin transporter gene with bipolar disorder among the Han Chinese].

OBJECTIVE: The serotonin transporter gene (SERT) plays an important role in the serotonin uptake into neurons. This paper reports a population and association study among the Han Chinese. METHODS: DNA were extracted from peripheral blood samples of 50 patients with bipolar disorder (DSM-IIIR), 170 unrelated healthy Han Chinese individuals and 10 healthy trios for polymerase chain reaction. The VNTR locus was amplified and PCR products were separated on the 2% agrose gel. RESULTS: All the three alleles(9,10 and 12 copies of repeat unit) reported in other studies were observed in this study with frequency 0.0029, 0.0676 and 0.9294, respectively. Four genotypes distributed in Caucasian: 12/12, 12/10, 12/9 and 10/10 were also found in the Han Chinese population. A significant difference in the allele frequency between the Han Chinese and Caucasian populations was found(P 0.000000001). No disequilibrium was observed after checking the Hardy-Weinberg equilibrium (P=0. 9995). The hereditary stability of this locus in accordance with the rules of Mendelian inheritance was demonstrated in the analysis of ten trios. In addition, a significant increase of frequency of the allele 10 in female patients with bipolar disorder was found (P=0. 043). CONCLUSION: The data of association study might indicate a different mechanism of aetiology of bipolar disorder in male and female.

Asian People↗

Finite element formulation of biphasic poroviscoelastic model for articular cartilage.

The purpose of the present study was to develop a computationally efficient finite element model that could be useful for parametric analysis of the biphasic poroviscoelastic (BPVE) behavior of articular cartilage under various loading conditions. The articular cartilage was modeled as the BPVE mixture of a porous, linear viscoelastic, and incompressible solid and an inviscid and incompressible fluid. A finite element (FE) formulation of the BPVE model was developed using two different algorithms, the continuous and discrete spectrum relaxation functions for the viscoelasticity of the solid matrix. These algorithms were applied to the creep and stress relaxation responses to the confined compression of articular cartilage, and a comparison of their performances was made. It was found that the discrete spectrum algorithm significantly saved CPU time and memory, as compared to the continuous spectrum algorithm. The consistency analysis for the present FE formulation was performed in comparison with the IMSL, a commercially available numerical software package. It was found that the present FE formulation yielded consistent results in predicting model behavior, whereas the IMSL subroutine produced inconsistent results in the velocity field, and thereby in the strain calculation.

Algorithms↗

[Loss of heterozygosity on chromosome RB1.20 locus and p110RB1 protein state in squmous cell carcinomas of larynx].

OBJECTIVE: To study the RB1 gene in squamous cell carcinoma of larynx(ISCC) and to find clue for discovering and locating new suppressor gene. METHODS: Loss of heterozygosity (LOH) of microsatellite polymorphic sequence on chromosomes 13 at RB1.20 locus of 58 LSCC patients were analyzed. The p110RB1 protein state was detected by immunohistochemical staining using the polyclonal antibody to the RB1 products. RESULTS: It showed that 3 cases in the preinvasive stage (i.e. carcinoma in situ) had no any LOH on chromosome 13. Forty percent of the 55 invasive LSCC showed LOH at RB1.20 locus. By immunohistochemical staining p110RB1 protein negative reaction was observed in 8 LSCCs in which 6 cases associated with LOH at RB1.20 locus. CONCLUSIONS: RB1 gene was inactivated in some LSCCs. It is putative that there is another tumor suppressor gene on chromosome 13 near by RB1.20 locas. The inactivation of the genes at the chromosome 13q region including RB1 involved genesis and development of invasive LSCC.

Carcinoma, Squamous Cell↗

[Inferior pulmonary ligament spindle-shaped covering on the anastomotic orifice in the surgery of cardiac carcinoma: experience in 772 patients with no anastomotic leakage or stricture successively].

OBJECTIVE: To prevent anastomotic leakage and stricture after the resection of cardiac carcinoma. METHODS: Since complications are the main causes of postoperative death and poor living quality, we modified anastomotic method, and projected anastomotic orifice to be covered with inferior pulmonary ligament(IPL) in spindle shape. RESULTS: From March 1987 to December 1996, 772 cases of cardiac carcinoma underwent surgical treatment with this method and no anastomotic leakage and stricture developed. CONCLUSION: The IPL has strong ability to adhere and heal. Anastomotic orifice is covered tightly and safely. No forth row 13 needed in not introsed anastomotic orifice, thus preventing stricture, because of lung expanding, IPL adheres to anastomotic orifice tightly, making stump space disappeared. IPL possesses well tenacity and can be used easily.

Adult↗

[Loss of heterozygosity on chromosome 13 in squamous cell carcinomas of the larynx].

OBJECTIVE: To locate lost region of tumor suppressor gene on chromosome 13q in squamous-cell carcinoma of the larynx (LSCC) and to provide clues and evidence for discovering and locating new suppressor gene. METHODS: Loss of heterozygosity (LOH) on chromosomes 13 was analyzed in 58 LSCC patients. By microsatellite polymorphic sequences in loci D13S765 (13q13), RB 1.20 (13q14.2), D13s133 (13q14.3) and D13S318 (13q21) on chromosome 13 by PCR. RESULTS: There weren't any LOH on chromosome 13q in 3 cases with preinvasive LSCC. Forty-five percentage (24/53) of the 53 invasive LSCC cases showed LOH at one or more loci on chromosome 13q region. The highest perentage of LOH on chromosome 13q was 52% (22/53) at D13S765 locus. CONCLUSION: The deletion region on chromosome 13q was located near by D13S765 locus which is centrimeric to RB1. In this region there is suppressor gene, which related to the genesis and developement of LSCC, possibly including RB1. The inactivation of these suppressor gene may be related to the genesis and developement of invasive LSCC.

Carcinoma in Situ↗

[Effects of octacosanol in food physiological parameters in tail-suspended rats].

The purposes of the experiment were to observe the physiological effects of octacosanol in food on tail-suspended rats and to investigate the possibility of using octacosanol in health food for astronauts. 24 male Wistar rats were randomly divided into free action control, tail-suspension and tail suspension plus octacosanol (TSO) groups. Octacosanol was emulsified into water by supersound and given to TSO rats with a dosage of 25 mg/kg wt d. The results showed that octacosanol elevated the weight of thymus, improved biomechanical properties of the femur and improved membrane fluidity of red blood cell. It suggests that octacosanol can counteract some effects of simulated weightlessness on rats. Therefore, octacosanol may be added to natural foods to benefit the health of cosmonauts.

Aerospace Medicine↗

[Suppression of transforming growth factor beta 1 on malignant phenotype in HL-60 cells].

OBJECTIVE: To study the effect of transforming growth factor beta 1 on tumor cells. METHOD: HL-60 cells were transfected with transforming growth factor beta 1 expression vector by electroporation. Stable cell clones resistant to G 418 were obtained after 2-3 week growth with the drug-containing medium. A series of malignant phenotype were compared between transfected and untransfected HL 60 cells. RESULTS: The growth speed of HL-60 cells which overexpressed transforming growth factor beta 1 mRNA decreased significantly. Clonigenecity in soft agarase and tumor formation in athymic mice were lower than those untransfected HL-60 cells. CONCLUSION: Suppression effect of transforming growth factor beta 1 on malignant phenotype in HL-60 cells were demonstrated.

Animals↗

Augmentation of tumor metastasis by platelet-activating factor.

The effect of platelet-activating factor (PAF) on experimental pulmonary metastasis by the B16F10 murine melanoma and the possible involvement of PAF in the activities of tumor necrosis factor alpha (TNF-alpha) and interleukin 1alpha (IL-1alpha) in tumor metastasis were investigated. i.p. injection of PAF enhanced the lung colonization in a dose- and time-dependent manner. PAF enhanced lung colonization when it was administered after, but not before, B16F10 inoculation. Multiple injections of PAF were more effective than a single injection. Neutralization of endogenous PAF with PAF antagonist BN50739 decreased lung colonization, suggesting that endogenous PAF plays an important role in pulmonary metastases. A single i.p. injection of TNF-alpha or IL-1alpha caused a marked enhancement in lung colonization. TNF-alpha- and IL-1alpha-mediated enhancement in lung colonies was significantly inhibited by BN50739. These results demonstrate that PAF has a metastasis-enhancing effect and is a mediator of the metastatic activities of TNF-alpha and IL-1alpha.

Animals↗

Immunologic distribution of an organic anion transport protein in rat liver and kidney.

A Na(+)-independent organic anion transport protein was recently cloned from rat liver using a Xenopus laevis oocyte expression system [E. Jacquemin, B. Hagenbuch, B. Stieger, A.W. Wolkoff, and P.J. Meier, Proc. Natl. Acad. Sci. USA 91: 133-137, 1994]. Although expression of this protein is sufficient for cells to transport the organic anion bromosulfophthalein, little is known about its cell biology or biochemical characteristics. Northern blot analysis performed under high-stringency conditions revealed hybridization with RNA only from liver and kidney; transcripts appeared the same in these two organs. Within kidney, hybridization was greatest when RNA extracted from the outer medulla was used. Immunoblot analysis revealed that in liver, the transporter was enriched in 0.1 M Na2CO3-extracted membranes and sinusoidal plasma membrane preparations, consistent with its being an integral membrane protein. This 80-kDa protein migrated as a 65-kDa protein after treatment with N-glycanase. Immunomorphological examination of liver revealed basolateral plasma membrane localization. In 0.1 M Na2CO3-extracted membranes of kidney, the transporter migrated as an 83-kDa protein on nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). On reduction, it resolved into peptides of 33 and 37 kDa. SDS-PAGE migration of the liver protein was unaffected by reduction. Immunomorphological examination of kidney revealed apical plasma membrane localization in the S3 segment of the proximal tubule of the outer medulla. Differential processing and trafficking of this transporter in liver and kidney may have important functional and regulatory consequences.

Adenosine Triphosphate↗

Manuduction of adhesive ankylosis of the knee under anesthesia.

This paper reports 60 cases of adhesive ankylosis of the knee treated by manuduction under anesthesia. Excellent and good effects were achieved in 50 cases (83%), and normal function of the knee joint was maintained in 35 of the 40 cases followed up for more than one year.

Adolescent↗

[A study of LOH on chromosome 9p21 region D9S319 locus of laryngeal carcinoma].

Loss of Heterozygosity (LOH) on chromosome 9p21 (D9S319) from fifty-four laryngeal cancer patients has been examined by using the PCR technique of DNA microsatellite markers in this study. The results showed that the LOH on 9p21 was 100% present (2/2) in in situ carcinomas and 66% (29/44) in invasive carcinomas. Therefore, these results suggest that there is a tumor suppressor gene located on 9p21 region. Its inactivation was related to laryngeal carcinoma and it was an early event.

Carcinoma in Situ↗

Stable inducible expression of a functional rat liver organic anion transport protein in HeLa cells.

Recently we expression cloned a rat liver organic anion transport protein in Xenopus laevis oocytes (Jacquemin, E. Hagenbuch, B, Stieger, B., Wolkoff, A.W., and Meier, P.J.,(1994) Proc. Natl. Acad. Sci. U.S.A. 91, 133-137). In the present study, we have stably transfected the cDNA encoding this protein into HeLa cells by using a vector containing a zinc-inducible promoter. The parent cells have virtually no baseline transport of [35S]sulfobromophthalein, whereas the induced transfected cells express a novel 74-kDa protein and avidly transport this ligand. Transport by these cells is saturable (Km = 3.3 microM, Vmax = 257 pmol/min/mg protein), bidirectional, and highly temperature-dependent. In the presence of albumin, uptake of [35S]sulfobromophthalein requires the presence of extracellular Cl, whereas in the absence of albumin, this C1- dependence is not seen. These studies indicate that cellular uptake of sulfobromophthalein does not result from direct interaction with the plasma membrane lipid bilayer but rather requires the presence of a specific plasma membrane transporter.

Albumins↗

Basal promoter of the rat connexin 32 gene: identification and characterization of an essential element and its DNA-binding protein.

The connexin 32 (Cx32) gene, a member of a multigene family, is expressed preferentially in the liver. The basal promoter complex of the rat Cx32 gene was previously localized to a 146-bp region (map positions [mp] -179 to -34) immediately upstream of the first exon. To investigate the biochemical factors contributing to the basal promoter activity, nuclear protein-DNA complexes within this region (mp -177 to -106) were investigated by using a DNA mobility shift assay. Three DNA-protein binding activities, termed Cx32-B1, Cx32-B2, and Cx32-B3, were identified with nuclear protein extracts from hepatoma cell lines, HuH7 and FAO-1. However, only Cx32-B2 binding activity was detected in nuclear protein extract from normal rat liver tissue. This activity was significantly more abundant in rat liver tissue than in hepatoma cell lines and tissues from various other organs. By using methylation interference footprinting, the Cx32-B2 complex was localized to the region between mp -152 and -127 and a DNA probe containing this region bound to a 60-kDa protein in rat liver nuclear extracts. Mutation of two nucleotides in the Cx32-B2 binding site abrogated the formation of the Cx32-B2 protein-DNA complex and significantly reduced the transcriptional activity of the Cx32 promoter. These results indicate that the Cx32-B2 complex is an essential component of the rat Cx32 basal promoter and is likely a major factor in the preferential expression of this gene in the liver.

Animals↗