Oral mucosal conditions and some related factors in 140 Uygur centenarians

OBJECTIVE

To investigate the condition of the oral mucosae in Xinjiang Uygur centenarians and explore some related factors.

METHODS

The oral mucosae and mucosal exfoliative cells of 140 Xinjiang Uygur centenarians were examined. Saliva and blood were collected from some centenarians. Salivary immunoglobulins (IgA, IgM, IgG), complements (C3 and C4), nitrous oxide (NO), 10 trace elements, serum sex hormones, thyroid hormones and osteocalcin (OST) were analysed using immunoglobulin, complement and NO kits, an ionochromatophotometer, and the kits for sex hormones and thyroid hormones, and fluorescence enzyme-linked immunosorbent assay, respectively.

RESULTS

Most centenarians (64.29%) had normal labial, buccal, palatal and gingival mucosae. The abnormal changes in mucosae were mainly vascular nevus patches and senile plaques. Their mucosal exfoliative cells showed similar characteristics to those in elderly Han. The centenarians who had normal mucosae had higher level of the trace element molybdenum (Mo) in their saliva than who had abnormal mucosae (P < 0.01).

CONCLUSION

The oral mucosal condition of Uygur centenarians was generally good. The abnormal changes in oral mucosae of the centenarians were lesions not harmful to health and may be related to the lower level of Mo in their saliva.

Smad6 as a transcriptional corepressor

Smad6 and Smad7, a subgroup of Smad proteins, antagonize the signals elicited by transforming growth factor-beta. These two Smads, induced by transforming growth factor-beta or bone morphogenetic protein (BMP) stimulation, form stable associations with their activated type I receptors, blocking phosphorylation of receptor-regulated Smads in the cytoplasm. Here we show that Smad6 interacts with homeobox (Hox) c-8 as a transcriptional corepressor, inhibiting BMP signaling in the nucleus. The interaction between Smad6 and Hoxc-8 was identified by a yeast two-hybrid approach and further demonstrated by co-immunoprecipitation assays in cells. Gel shift assays show that Smad6, but not Smad7, interacts with both Hoxc-8 and Hoxa-9 as a heterodimer when binding to DNA. More importantly, the Smad6-Hoxc-8 complex inhibits interaction of Smad1 with Hoxc-8- and Smad1-induced transcription activity. These data indicate that Smad6 interacts with Hox transcription factors as part of the negative feedback circuit in the BMP signaling pathway.

1H dynamic nuclear polarization in supercritical ethylene at 1.4 T

(1)H dynamic nuclear polarization (DNP) has been measured in supercritical ethylene in the pressure range 60-300 bar in an external field of 1.4 T. A single-cell sapphire tube was used as a high-pressure cell, and powdered 1,3-bisdiphenylene-2-phenyl allyl (BDPA) free radicals were added and distributed at the wall of the cell. At all pressures the dominant DNP mechanism was a positive Overhauser enhancement, caused by proton-electron contact interactions at the fluid/solid radical interface. The observed enhancements varied from 12 at 60 bar to 17 at 300 bar. Besides the Overhauser enhancement, small solid state and thermal mixing enhancements also were observed, indicating that part of the ethylene was adsorbed at the radical surface for a prolonged time. The impacts of the experimental conditions on the Overhauser enhancement factors are discussed, and enhancements of at least 40-60 are estimated when the EPR saturation factor and the leakage factor become maximal. These data indicate that DNP-enhanced NMR has the potential of extending the impact of NMR in research areas involving supercritical fluids.

[Reactivation of denatured lysozyme with immobilized molecular chaperones GroE]

The molecular chaperones GroEL and GroES were expressed in recombinant E. coli and purified by anion exchange chromatography. The renaturation of the denatured lysozyme with the free and immobilized GroEL/ES or GroEL was studied. We show here that using free GroEL alone could reactive the denatured lysozyme up to a relative activity of over 90%. The immobilized GroEL was also effective for promoting lysozyme refolding. Moreover, the optimal temperature (i.e., 37 degrees C) and (pH(i.e., 6 to 8) for the immobilizde GroEL-facilitated lysozyme refolding operation were determined. Under the optimal condition, the activity of lysozyme could be recovered up to 85%. In addition, the immobilized GroEL was repeatedly used five times without loss of its renaturation ability, indicating its potentiality to be used in practical downstream bioprocesses.

[Study on the inhibition of nude mice transplantation tumor growth by telomerase ribozyme]

OBJECTIVE

To explore whether telomerase ribozyme could inhibit the growth of nude mice transplantation tumor.

METHODS

A xenograft human-nude mouse model was constructed. A total of 24 mice were divided into 4 groups, namely, the saline control(Group 1), the blank plasmid control(Group 2), the 20 microg/mouse/day p(XJ-neo-teloRZ)(Group 3) and the 30 microg/mouse/day p(XJ-neo-teloRZ)(Group 4). All plasmids were packaged by lipofectamine and used for subcutaneous, continuous infusions over 14 days. Tumor measurements and observations of animal behavior were recorded daily. On completion of the study, the mice were killed by cervical dislocation and their organs were removed, weighed, and stored in formaldehyde for histological examination. The telomerase activities of tumor tissues of each group were also detected.

RESULTS

The telomerase ribozyme effectively inhibited the telomerase activities of tumor tissues and promoted the apoptosis of tumor cells. The in vivo studies showed a significant decrease in tumor size in mice treated with p(XJ-neo-teloRZ) when compared to the mice treated with controls. Furthermore, the in vivo effect of p(XJ-neo-teloRZ) was dose dependent.

CONCLUSION

Telomerase ribozyme is a powerful telomerase inhibition agent; probably it could be effective in tumor gene therapy.

[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.

[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.

Simple and rapid assay for acetaminophen and conjugated metabolites in low-volume serum samples

The use of marker compounds for estimating drug metabolic capacity or pharmacokinetic parameters is common in the biological sciences. Often small laboratory animals are used and thus sample size is a limiting concern. In this report, we describe an assay we developed for measuring the concentration of acetaminophen and its conjugated metabolites in low-volume serum samples. Acetaminophen and metabolites were removed from 10 microl serum samples by a single-step 6% (v/v) perchloric acid deproteination using theophylline as internal standard. Samples were separated in a pH 2.2 sodium sulfate-acetonitrile mobile phase at a flow-rate of 1.5 ml/min on a 15 cm octadecylsilyl column at room temperature. Analytes were detected at a wavelength of 254 nm. The resulting chromatograms showed no interfering peaks from endogenous serum components. The concentration ranges measured were 1.56-200 microg/ml for acetaminophen and acetaminophen sulfate and 3.91-500 microg/ml for acetaminophen glucuronide. The assay was linear in the range of concentrations analyzed. The intra-day and inter-day coefficient of variation ranged from 0.4 to 8.2% and 0.2 to 12.3% for acetaminophen, 0.5 to 12.9% and 0.3 to 16.1% for acetaminophen glucuronide, and 0.4 to 8.1% and 0.2 to 14.3% for acetaminophen sulfate, respectively. Results from the experiments show that acetaminophen and its conjugated metabolites can easily and reproducibly be measured in low-volume serum samples and thus may offer an additional method to measure these compounds when the volume of biological samples may be limited.

Tentative association of the serotonin transporter with schizophrenia and unipolar depression but not with bipolar disorder in Han Chinese

The serotonin transporter gene (SERT) plays an important role in the serotonin uptake into neurons. Recently, several polymorphisms including a variable-number-tandem-repeat (VNTR) in the second intron and an insertion/deletion polymorphism (5-HTT linked polymorphic region, 5-HTTLPR) were identified and reported to be associated with a variety of mental illnesses, including major depression, bipolar disorder, anxiety-related traits, and autism. In our study, we performed an association study between the SERT VNTR polymorphism and schizophrenia (n = 260), bipolar disorder (n = 137), and unipolar depression (n = 33) in the Han Chinese. A large group of ethnically matched control individuals (n = 362) were also genotyped. Allele 12 of the VNTR polymorphism was associated with schizophrenia (P = 0.007) and unipolar depression (P = 0.011). Bipolar disorder was not associated with the VNTR (P = 0.93). Thus, we conclude that the SERT VNTR polymorphism may be a risk factor for both schizophrenia and unipolar depression, but not for bipolar disorder, in the Han Chinese.

Tentative novel mechanism of the bystander effect in glioma gene therapy with HSV-TK/GCV system

Although many works support gap junctional intercellular communication (GJIC) having a close relation to bystander cell killing in herpes simplex virus thymidine kinase (HSV-TK) gene and ganciclovir (GCV) treatment, our previous work suggested that other factors involved in bystander effect besides GJIC exist. To confirm our primary work, we evaluated the mode of the bystander cell (C6) co-cultured with TK-positive cells (TF10.2) in our designed "insert plates" in which two cell lines could be separated but share the same medium. Another method that we used was adding the supernatant from the medium of GCV-treated TF10.2 cells to the wild type C6. Growth inhibition of the bystander cells was observed despite the absence of GJIC. In addition, apoptotic cell death of TK+ cells and bystander cells was obvious. These studies suggested that other pathways besides cell-cell contacts may play a role in bystander cell killing; the factors released from TK-positive cells could induce apoptosis of bystander cells.

[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.

[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.

[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.

[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.

Two new polyacetylenes from Artemisia eriopoda

The aerial parts of Artemisia eriopoda (Compositae) afforded two new C (17)-polyacetylenes. Based on their IR, UV, EIMS, (1)H- and (13)C-NMR (DEPT) spectral data, the structures were elucidated to be (1,8 E,13 Z,16)-heptadecatetraene-4,6-diyne-3,11,12-triol and (1,8 E,12 E,14 Z)-heptadecatetraene-4,6-diyne-3,11-diol.

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.

[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.

[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.

[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.