[Identification and visualization of virus-like particles in peripheral blood mononuclear cells]

OBJECTIVE

PBMCs from patients with chronic hepatitis C were examined by electron microscopy (EM), immune EM (IEM) combined with immunohistochemistry to trace the infection and morphology of HCV in the PBMCs.

METHODS

The PBMCs from 28 patients with chronic hepatitis C were analyzed firstly for HCV RNA and HCV antigens by RT-PCR and immunohistochemistry respectively. The PBMCs with positive HCV RNA and HCV antigens were then observed by electron microscopy.

RESULTS

The positive rate of HCV RNA and HCV antigens were 77.27% (17/22) and 75.00% (21/28), respectively. Two types of polymorphic HCV-like particles with diameter of approximately 65 nm and 110 nm were observed in cytoplasmic vesicles of the PBMCs from HCV Ag positive patients. 10 patients with HCV Ag over expression were studied by electron microscopy and immune election microscopy. The budding phenomenon of the particles could be also visualized in the cytoplasmic vesicles of the PBMCs. Some ultrastructural changes showed an increased ratio of cytoplasm to nucleus and pyknosis of nucleus was also suggestive of the virus infection.

CONCLUSIONS

The EM study demonstrated the infection and replication of HCV in the PBMCs of chronic hepatitis C patients by morphology and morphogenesis.

p21WAF1/CIP1 antisense therapy radiosensitizes human colon cancer by converting growth arrest to apoptosis

Substantial evidence suggests that loss of cellular p21WAF1/CIP1 results in increased apoptotic killing by ionizing radiation. We hypothesized that a p21 antisense (AS) oligodeoxynucleotide (ODN) could be used to sensitize cancer cells to radiotherapy. In vitro treatment of colon cancer cells (HCT116/p21+/+) with p21 AS ODN (200 nM) led to inhibition of radiation-induced p21 expression (>95% inhibition, 0-30 Gy), resulting in a loss of G1 arrest and an enhancement of apoptosis to comparable levels and with similar kinetics to HCT116/p21-/- cells (approximately 60% apoptotic cells at 96 h after 10 Gy). In vivo, p21 AS ODN in combination with radiation (i.p. ODN for 6 days at 20 mg/kg/day and 15 Gy) increased apoptosis in s.c. p21+/+ tumors in nude mice to levels similar to those of p21-/- tumors (2-fold at 24 h postirradiation) and improved radiocurability of p21+/+ tumors to levels comparable to those of p21-/- tumors (p21+/+, two of eight cures versus p21-/-, two of nine cures). Our findings suggest that p21 AS treatment may be a rational approach to improve conventional radiotherapy outcomes.

Associations between socioeconomic status and cardiovascular risk factors in an urban population in China

INTRODUCTION

In developed countries socioeconomic status has been proven to be an important factor in the progression of cardiovascular disease. The present article reports the results of a cross-sectional assessment to investigate the association between socioeconomic status and cardiovascular risk factors in a Chinese urban population.

METHODS

In 1996, a behavioural risk factor survey was carried out in Tianjin, the third largest city in China. A sample of 4000 people aged 15-69 years, stratified by sex and 10-year age groups, was drawn randomly from urban areas of the city. The present study covers respondents aged 25-69 years (1615 men and 1592 women). Four socioeconomic indicators (education, occupation, income, and marital status), blood pressure, body mass index, and cigarette smoking were determined in the survey.

RESULTS

Educational level seemed to be the most important measure of the four socioeconomic indicators in relation to the cardiovascular risk factors in the study population. People with lower socioeconomic status had higher levels of cardiovascular risk factors. The association between socioeconomic status and cardiovascular risk factors was more consistent among women than men.

DISCUSSION

Our findings do not seem to differ from those observed in developed countries.

Single-strand conformation polymorphism analysis by capillary and microchip electrophoresis: a fast, simple method for detection of common mutations in BRCA1 and BRCA2

As a result of intensive studies on hereditary breast and ovarian cancers, two breast cancer susceptibility genes, BRCA1 and BRCA2, have been identified. In each gene, a small number of specific mutations have been found at relatively high frequency in certain ethnic populations. The mutations, 185delAG and 5382insC in BRCA1 and 6174delT in BRCA2, have been identified as common mutations in the Ashkenazi Jewish population, with a combined frequency of 2.0 to 2.5%. Women who have one of the above three common mutations are at a high risk of developing breast or ovarian cancer. Consequently, accurate and cost-effective detection of these three mutations may have important implications for risk assessment in susceptible women and men. In this report, we describe a fast and simple capillary electrophoresis (CE)-based method using a polymer network for screening the three common mutations in BRCA1 and BRCA2. Fluorescent dye-labeled primers (6-FAM-tagged) were used to amplify three DNA fragments of 258, 296, and 201 bp for detection of the 185delAG, 5382insC, and 6174delT mutations, respectively. After the PCR products were denatured, a single-strand conformation polymorphism (SSCP) profile could be obtained for each mutation in less than 10 min by CE in a polymer network. We demonstrate the potential provided by translating this assay to the microchip format where the SSCP analysis is complete in 120 s, representing only a fraction of the reduction in analysis time that can be achieved with microchip technology. The speed and simplicity of the SSCP methodology for detection of these mutations make it attractive for use in the clinical diagnostic laboratory.

Diverse behavioural defects caused by mutations in Caenorhabditis elegans unc-43 CaM kinase II

Calcium/calmodulin-dependent serine/threonine kinase type II (CaMKII) is one of the most abundant proteins in the mammalian brain, where it is thought to regulate synaptic plasticity and other processes. Activation of the multisubunit kinase by calcium is effectively cooperative and can persist long after transient calcium rises. Despite extensive biochemical characterization of CaMKII and identification of numerous in vitro kinase targets, little is known about its function in vivo. Here we report that unc-43 encodes the only Caenorhabditis elegans CaMKII. A gain-of-function unc-43 mutation reduces locomotory activity, alters excitation of three muscle types and lengthens the period of the motor output of a behavioural clock. Null unc-43 mutations cause phenotypes generally opposite to those of the gain-of-function mutation. Mutations in the unc-103 potassium channel gene suppress a gain-of-function phenotype of unc-43 in one tissue without affecting other tissues; thus, UNC-103 may be a tissue-specific target of CaMKII in vivo.

[The significance of detection of hepatitis C virus RNA in peripheral blood mononuclear cells of patients with chronic hepatitis C]

OBJECTIVE

To determine the role of peripheral blood mononuclear cells (PBMCs) in hepatitis C virus (HCV) infection.

METHODS

HCV RNA, HCV antigen and Fas antigen were detected in PBMCs of 22 patients with chronic hepatitis C, 21 renal dialysis patients with anti-HCV positive and 12 health blood donors as normal controls. All specimens were studied by electronic microscope (EM).

RESULTS

(1) The positive rate of HCV RNA in PBMCs of 22 patients with hepatitis C was 77.3% (17/22). (2) EM showed that HCV particles replicated in PBMCs of the patients with HCV infection, but not in the serum of patients with negative HCV RNA and healthy controls. (3) HCV RNA were positive both in the serum and PBMCs of 8 patients with HCV particles positive and had a close relationship with HCV antigen and Fas antigen. The expression of HCV and apoptosis were found in the cytoplasm of PBMCs in these 8 patients.

CONCLUSION

(1) Hepatitis C virus could replicate in PBMCs and produce infectious HCV particles. (2) HCV in PBMCs may act as the source of reinfection for HCV and lead to persistent infection and recurrence.

[Acute toxicity of Stephania cepharantha]

The acute toxicity of Stephania cepharantha was studied, LD50 of aqueous extract of its wet and dry root tuber oral were 41.4 g/kg and 22.9 g/kg respectively.

Apoptosis induction by a novel anti-prostate cancer compound, BMD188 (a fatty acid-containing hydroxamic acid), requires the mitochondrial respiratory chain

We recently developed a class of novel anti-prostate cancer compounds, cyclic hydroxamates that elicit a potent apoptotic response in many tumor cells cultured in vitro (D.G. Tang et al., Biochem. Biophys. Res. Commun., 242: 380-384, 1998). The lead compound, termed BMD188, induces programmed cell death in a variety of prostate cancer cells in vitro as well as in vivo (L. Li et al., Anticancer Res., 19: 51-70, 1999). BMD188 kills androgen-independent prostate cancer cells as well as prostate cancer cells with a multidrug-resistance phenotype. The apoptotic effect of BMD188 in prostate cancer cells does not depend on cell cycle, p53 status, or its purported target, arachidonate 12-lipoxygenase, but does require caspase activation and seems to involve mitochondria. To synthesize more specific and effective anti-prostate cancer hydroxamic acid compounds, it is important to understand their mechanism(s) of action. In the present study, we studied the role of mitochondrial respiratory chain (MRC) in BMD188-induced apoptosis in androgen-independent prostate cancer PC3 cells and compared its effect with that of staurosporine (STS), a widely used apoptosis inducer. Several lines of evidence indicate that BMD188-induced cell death depends on MRC: (a) the death could be significantly inhibited by several complex-specific respiration inhibitors; (b) respiration-deficient rho0 cells were more resistant than wild-type parent cells to apoptosis induction by BMD188; and (c) BMD188 induced a rapid increase in reactive oxygen species in mitochondria, an up-regulation of cytochrome c oxidase subunits, a biphasic alteration (i.e., an early hyperpolarization, followed by later hypopolarization) in the mitochondrial membrane potential (delta psi(m)), dramatic changes in mitochondrial morphology and distribution prior to caspase activation, and an abnormal proliferation of mitochondria at the ultrastructural level. By contrast, STS-induced PC3 apoptosis seemed not to depend on MRC. Taken together, the data suggest that the MRC represents a functional target for anti-prostate cancer hydroxamates.

Changes in blood pressure, body mass index, and salt consumption in a Chinese population

BACKGROUND

The prevalence of hypertension among the population of Tianjin is one of the highest in China. We attempted to assess the changes in blood pressure, body mass index, and salt consumption in Tianjin from 1989 to 1996.

METHODS

Two independent cross-sectional population surveys with the representative samples of 14,046 persons in 1989 and 2,000 persons in 1996 were carried out in Tianjin. A salt surveillance system was established with four salt consumption surveys (in 1992, 1993, 1994, and 1996) to estimate the changes in salt consumption at the household level.

RESULTS

From 1989 to 1996, the prevalence of hypertension and obesity decreased among people aged 45-64 years in both genders. Mean systolic blood pressure decreased significantly in women and leveled off in men. Diastolic blood pressure increased significantly. Body mass index remained unchanged. The unfavorable trends were mainly attributable to the negative changes in younger people (15-34 years) in both genders. There were no changes in salt consumption between 1992 and 1996 at the house level.

CONCLUSIONS

There was a favorable development in prevalence of hypertension and obesity among individuals in the age group of 45-64 years in the study population. Health education needs to pay more attention to young people.

The administration schedule of cyclin-dependent kinase inhibitor gene therapy and etoposide chemotherapy is a major determinant of cytotoxicity

Cyclin-dependent kinase inhibitors are potent suppressors of cell growth and have been proposed as targets for gene replacement therapy in cancer. Expression of either p16INK4a or p21WAF1 protected cells from the cytotoxic effects of the topoisomerase II inhibitor, etoposide. A lower level of p53 was induced in CDK inhibitor-expressing etoposide-exposed cells suggesting that protection may be due to lower levels of DNA damage in the growth arrested cells. Exposure of human osteosarcoma cells to either p16INK4a or p21WAF1 prior to and during etoposide therapy protected cells against etoposide-induced cell death. Infection of the cells by Ad-p16INK4a or Ad-p21WAF1 following exposure to etoposide resulted in loss of the protective effect with evidence of enhanced growth inhibition. The results suggest that the schedule of administration of DNA damaging etoposide chemotherapy and cell cycle inhibitory therapy is a major determinant of the resulting cytotoxicity.

Structural basis of multifunctional bovine mitochondrial cytochrome bc1 complex

The mitochondrial cytochrome bc1 complex is a multifunctional membrane protein complex. It catalyzes electron transfer, proton translocation, peptide processing, and superoxide generation. Crystal structure data at 2.9 A resolution not only establishes the location of the redox centers and inhibitor binding sites, but also suggests a movement of the head domain of the iron-sulfur protein (ISP) during bc1 catalysis and inhibition of peptide-processing activity during complex maturation. The functional importance of the movement of extramembrane (head) domain of ISP in the bc1 complex is confirmed by analysis of the Rhodobacter sphaeroides bc1 complex mutants with increased rigidity in the ISP neck and by the determination of rate constants for acid/base-induced intramolecular electron transfer between [2Fe-2S] and heme c1 in native and inhibitor-loaded beef complexes. The peptide-processing activity is activated in bovine heart mitochondrial bc1 complex by nonionic detergent at concentrations that inactivate electron transfer activity. This peptide-processing activity is shown to be associated with subunits I and II by cloning, overexpression and in vitro reconstitution. The superoxide-generation site of the cytochrome bc1 complex is located at reduced bL and Q*-. The reaction is membrane potential-, and cytochrome c-dependent.

Catecholamine synthesis is mediated by tyrosinase in the absence of tyrosine hydroxylase

Catecholamine neurotransmitters are synthesized by hydroxylation of tyrosine to L-dihydroxyphenylalanine (L-Dopa) by tyrosine hydroxylase (TH). The elimination of TH in both pigmented and albino mice described here, like pigmented TH-null mice reported previously (Kobayashi et al., 1995; Zhou et al., 1995), demonstrates the unequivocal requirement for catecholamines during embryonic development. Although the lack of TH is fatal, TH-null embryos can be rescued by administration of catecholamine precursors to pregnant dams. Once born, TH-null pups can survive without further treatment until weaning. Given the relatively rapid half-life of catecholamines, we expected to find none in postnatal TH-null pups. Despite the fact that the TH-null pups lack TH and have not been supplemented with catecholamine precursers, catecholamines are readily detected in our pigmented line of TH-null mice by glyoxylic acid-induced histofluorescence at postnatal day 7 (P7) and P15 and quantitatively at P15 in sympathetically innervated peripheral organs, in sympathetic ganglia, in adrenal glands, and in brains. Between 2 and 22% of wild-type catecholamine concentrations are found in these tissues in mutant pigmented mice. To ascertain the source of the catecholamine, we examined postnatal TH-null albino mice that lack tyrosinase, another enzyme that converts tyrosine to L-Dopa but does so during melanin synthesis. In contrast to the pigmented TH-null mice, catecholamine histofluorescence is undetectable in postnatal albino mutants, and the catecholamine content of TH-null pups lacking tyrosinase is 18% or less than that of TH-null mice with tyrosinase. Thus, these extraordinary circumstances reveal that tyrosinase serves as an alternative pathway to supply catecholamines.

Evidence for the head domain movement of the rieske iron-sulfur protein in electron transfer reaction of the cytochrome bc1 complex

The three-dimensional structure of the mitochondrial cytochrome bc1 complex suggests that movement of the extramembrane domain (head) of the Rieske iron-sulfur protein (ISP) may play an important role in electron transfer. Such movement requires flexibility in the neck region of ISP, since the head and transmembrane domains of the protein are rather rigid. To test this hypothesis, Rhodobacter sphaeroides mutants expressing His-tagged cytochrome bc1 complexes with cysteine substitution at various positions in the ISP neck (residues 39-48) were generated and characterized. The mutants with a single cysteine substitution at Ala42 or Val44 and a double cysteine substitution at Val44 and Ala46 (VQA-CQC) or at Ala42 and Ala46 (ADVQA-CDVQC) have photosynthetic growth rates comparable with that of complement cells. Chromatophore membrane and intracytoplasmic membrane (ICM) prepared from these mutants have cytochrome bc1 complex activity similar to that in the complement membranes, indicating that flexibility of the neck region of ISP was not affected by these cysteine substitutions. Mutants with a double cysteine substitution at Ala42 and Val44 (ADV-CDC) or at Pro40 and Ala42 (PSA-CSC) have a retarded (50%) or no photosynthetic growth rate, respectively. The ADV-CDC or PSA-CSC mutant ICM contains 20 or 0% of the cytochrome bc1 complex activity found in the complement ICM. However, activity can be restored by the treatment with beta-mercaptoethanol (beta-ME). The restored activity is diminished upon removal of beta-ME but is retained if the beta-ME-treated membrane is treated with the sulfhydryl reagent N-ethylmaleimide or p-chloromercuribenzoic acid. These results indicate that the loss of bc1 complex activity in the ADV-CDC or PSA-CSC mutant membranes is due to disulfide bond formation, which increases the rigidity of ISP neck and, in turn, decreases the mobility of the head domain. Using the conditions developed for the isolation of His-tagged complement cytochrome bc1 complex, a two-subunit complex (cytochromes b and c1) is obtained from all of the double cysteine-substituted mutants. This suggests that introduction of two cysteines in the neck region of ISP weakens the interactions between cytochromes b, ISP, and subunit IV.

Determination of zinc contents in rabbits with cerebral ischemia by NAA and ICP-AES

Cerebral ischemia is an important cerebral vascular disease, and zinc is a necessary trace element for humans. In this work, a cerebral ischemia model of rabbit was established by operation. The samples of brain and serum in the animal models were collected. The Zn contents in the samples were determined by neutron activation analysis and inductively coupled plasma-atomic emission spectrometry. The results show the Zn contents in brain decreased 2 mo after cerebral ischemia, and Zn contents in serum decreased even more obviously. In addition, a positive correlation of Zn contents between left and right cerebral hemispheres was observed, and the positive correlation between brain and serum was also observed. A test of Chinese medicine was also carried out in the work. Two Chinese medicines were fed to rabbits with cerebral ischemia in the experiments. The results showed they probably can prevent the decrease of Zn contents in serum.

Structure and reaction mechanisms of multifunctional mitochondrial cytochrome bc1 complex

The cytochrome bc1 complex from bovine heart mitochondria is a multi-functional enzyme complex. In addition to electron and proton transfer activity, the complex also processes an activatable peptidase activity and a superoxide generating activity. The crystal structure of the complex exists as a closely interacting functional dimer. There are 13 transmembrane helices in each monomer, eight of which belong to cytochrome b, and five of which belong to cytochrome c1, Rieske iron-sulfur protein (ISP), subunits 7, 10 and 11, one each. The distances of 21 A between bL heme and bH heme and of 27 A between bL heme and the iron-sulfur cluster (FeS), accommodate well the observed fast electron transfers between the involved redox centers. However, the distance of 31 A between heme c1 and FeS, makes it difficult to explain the high electron transfer rate between them. 3D structural analyses of the bc1 complexes co-crystallized with the Qu site inhibitors suggest that the extramembrane domain of the ISP may undergo substantial movement during the catalytic cycle of the complex. This suggestion is further supported by the decreased in the cytochrome bc1 complex activity and the increased in activation energy for mutants with increased rigidity in the neck region of ISP.

GIS-based measures of environmental equity: exploring their sensitivity and significance

In order to determine whether principles of environmental justice have been violated, a large number of empirical studies have been carried out to ascertain whether minority and low-income populations are disproportionately exposed to industrial pollution. This study provides a comparative evaluation of two commonly employed proximity measures in GIS-based environmental equity assessment, examining their influence on the results of the analysis, and proposes a methodology for evaluating the significance of these results. 1990 census data on population characteristics and data from the 1995 EPA's toxic release inventory (TRI) for the City of Minneapolis, MN are used. These results also allow a preliminary assessment of environmental equity/inequity in potential exposure to airborne toxic chemicals for racial minorities, poor people and children in Minneapolis. In the third part of the paper we develop and employ a geographic randomization methodology for assessing the significance of these results.

The role of income and education in food consumption and nutrient intake in a Chinese population

The purpose of this study was to investigate the role of socio-economic status in the transition of food consumption and nutritional status in a Tianjin population and to identify some related underlying nutritional problems in this population. A random representative sample of appproximately nine million people in Tianjin was obtained using the stratified multistage cluster sampling method. A total of 2236 eligible subjects (1096 men and 1140 women) aged between 15 and 64 years were enrolled in the autumn of 1992. Food weighing plus a three-day food record method were used to assess food consumption and nutrient intakes. The population was categorized into four income groups by average per capita income and three educational groups by years of education. There were marked differences in daily mean consumption of foods among groups with different income levels and educational attainment after adjustment for confounding factors. The low income and/or least education group consumed more cereals while the high income and/or most educated group consumed more fruit, milk and meat. Due to the differences in food consumption, intakes of protein, fat, riboflavin, calcium, selenium, zinc and vitamin E increased while intakes of carbohydrate and manganese decreased with increasing levels of income and education. Vitamin A, calcium and riboflavin intakes were low in all groups classified by either income or education. Vitamin A intake was lower in the low income group than in the other three groups but intakes of calcium and riboflavin were higher in the high income and/or the most educated group than in the other groups. Socio-economic status plays an important role in food consumption and nutritional status in this population. Low intakes of vitamin A, calcium and riboflavin exist in all socio-economic groups. However, higher income and/or educational attainment contribute to increased intakes of calcium and riboflavin. Higher income also relates to an increased intake of vitamin A.

The hypoxia-responsive transcription factor EPAS1 is essential for catecholamine homeostasis and protection against heart failure during embryonic development

Mice lacking the hypoxia-inducible transcription factor EPAS1 die at mid-gestation. Despite normal morphological development of the circulatory system, EPAS1-deficient mice display pronounced bradycardia. In addition to the vascular endothelium, EPAS1 is expressed intensively in the organ of Zuckerkandl (OZ), the principle source of catecholamine production in mammalian embryos. EPAS1-deficient embryos contained substantially reduced catecholamine levels. Mid-gestational lethality was rescued by administration of the catecholamine precursor DOPS to pregnant females. We hypothesize that EPAS1 expressed in the OZ senses hypoxia during mid-gestational development and translates this signal into an altered pattern of gene expression, leading to increases in circulating catecholamine levels and proper cardiac function.

Flexibility of the neck region of the rieske iron-sulfur protein is functionally important in the cytochrome bc1 complex

The crystal structure of the mitochondrial cytochrome bc1 complex suggests that movement of the extramembrane (head) domain of the Rieske iron-sulfur protein (ISP) is involved in electron transfer. Such movement requires flexibility in the neck region of ISP. To test this hypothesis, Rhodobacter sphaeroides mutants expressing His-tagged cytochrome bc1 complexes with altered ISP necks (residues 39-48) were generated and characterized. Mutants with increased rigidity of the neck, generated by a double-proline substitution at Ala-46 and Ala-48 (ALA-PLP) or by a triple-proline substitution of ADV at residues 42-44 (ADV-PPP), have retarded (50%) or no photosynthetic growth, respectively. However, the mutant with a shortened neck, generated by deleting ADV (DeltaADV), has a photosynthetic growth rate comparable to that of complement cells, indicating that the length of the ISP neck is less critical than its flexibility in support of photosynthetic growth. The DeltaADV and ALA-PLP mutant membranes have 10 and 30% of the cytochrome bc1 complex activity found in the complement membrane, respectively, whereas the ADV-PPP mutant membrane contains no cytochrome bc1 complex activity. The loss of cytochrome bc1 complex activity in the DeltaADV membrane is attributed to improper docking of the head domain of ISP on cytochrome b, as indicated by a drastic change in the EPR characteristics of the Rieske iron-sulfur cluster. The loss of cytochrome bc1 complex activity in the ALA-PLP and ADV-PPP mutant membranes results from the decreased mobility of the ISP head domain due to the increased rigidity of the ISP neck. The ALA-PLP mutant complex has a larger activation energy than the wild-type complex, suggesting that movement of the head domain decreases the activation energy barrier of the cytochrome bc1 complex. Using the conditions developed for the isolation of the His-tagged complement cytochrome bc1 complex, a two-subunit complex (cytochromes b and c1) was obtained from the DeltaADV and ADV-PPP mutants, indicating that mutations at the neck region of ISP weaken the interactions among cytochrome b, ISP, and subunit IV.

[Effect of TNF-alpha monoclonal antibody on tissue lipopolysaccharide-binding protein mRNA expression in rats after thermal injury]

OBJECTIVE

To explore the effects of tumor necrosis factor-alpha (TNF-alpha) monoclonal antibody (MAb) on tissue TNF-alpha and lipopolysaccharide-binding protein (LBP) mRNA expression, and multiple organ dysfunction in rats after thermal injury.

METHOD

24 male Wistar rats were subjected to a 35% total body surface area full-thickness thermal injury.

RESULT

The tissue TNF-alpha and LBP mRNA expressions of liver, lung, intestine, and kidney were markedly increased (P < 0.05 approximately equal 0.01) after thermal injury. Treatment with TNF-alpha MAb could significantly lower TNF-alpha mRNA expression of lung, intestine and kidney, but had no effect on liver TNF-alpha mRNA expression (P > 0.05). Similarly, the tissue LBP mRNA expression also decreased significantly (36.0% - 72.9%), and returned to normal in lung, intestine and kidney. In addition, biochemical parameters including GPT, TBiL, BUN, CK-MB, and LDH were markedly elevated after thermal injury, and decreased significantly after treatment with TNF-alpha MAb.

CONCLUSION

The increase of tissue TNF-alpha gene expression caused by thermal injury might be associated with a marked elevation of tissue LBP mRNA expression, which could contribute to the development of multiple organ dysfunction. The early use of TNF-alpha MAb seems to be effective in inhibiting significant LBP mRNA expression in various tissues and ameliorating multiple organ damage after major thermal injury.

[Clinical significance of detection of IL-2R for non-small cell lung cancer.]

BACKGROUND

To explore the clinical significance of SIL-2R of serum and IL-2R expression of cancer tissue in non-small cell lung cancer.

METHODS

SIL-2R levels in the serum and IL-2R expression in cancer tissues were detected in 42 non-small cell lung cancer by ELISA and immunohistochemistry respectively.

RESULTS

Serum SIL-2R level was significantly higher in lung cancer group than that in normal control group ( P < 0. 05) , and significantly higher in stage III, IV disease than that in stage I, II disease ( P < 0. 05) , but it was not associated with histological classification of the cancer ( P > 0. 05) . IL-2R expression was significantly higher in lung cancer tissue than that in normal lung tissue ( P < 0. 05) and was significantly higher in stage III, IV cancer than that in stage I, II cancer ( P < 0. 05) . But it was not related to cancer types ( P > 0. 05) .

CONCLUSIONS

The results suggest that detection of serum SIL-2R and IL-2R expression of the cancer tissue might be useful to predict stages of cancer and monitor the prognosis of patients with lung cancer.

[Preparation of acyclovir-polybutylcyanoacrylate-nanoparticles by emulsion polymerization method]

The aim of this study was to optimize the conditions and technology of preparing acyclovir-polybutylcyanoacrylate-nanoparticles (ACV-PBCA-NP) which has the diameter of about 100 nm and the shape of a sphere. The influential factors on sphericization were observed by single factor optimization. The preparation conditions and technology were optimized by the even design method. The contents of acyclovirin in acyclovir polybutyloganoacrylate nanoparticles were determined by HPLC. The optimum conditions and technology of preparing acyclovir polybutylcyanoacrylate nanoparticles were decided and put into use. The average diameter of the ACV-PBCA-NP thus prepared was 108.5 +/- 94.8 (n = 588). Its embedding ratio was 71.8%, and drug loading was 18.5%. The results suggest that the conditions and technology of preparing ACV-PBCA-NP presented in this paper are stable and practical.

Osteoarthrosis of the temporomandibular joint induced by intra-articular injection of lactate dehydrogenase: an experimental study in adult rabbits

OBJECTIVE

The purpose of this study was to establish an animal model of osteoarthrosis in the temporomandibular joint (TMJOA) by injecting lactate dehydrogenase (LDH) into the maxillary compartments of TMJs in adult rabbits.

METHODS

Adult New Zealand white rabbits were randomly divided into four groups (A through D) of five animals each. The A and B groups were used as a control. The maxillary compartments of the C and D group (TMJs) were injected with 0.1 mL of LDH in two different concentrations. The TMJ samples were analyzed histologically and with a scanning electron microscope four different times after injection.

RESULTS

The animals that had been injected with LDH at two different concentrations showed similar results. The TMJs had changes typical of OA in early to moderate stages. No pathologic changes could be found in the TMJs of the control groups.

CONCLUSIONS

The results suggest that LDH may be of use in establishing an animal model of TMJOA.

[Effects of ligustrazine on myocardium and coronary artery]

OBJECTIVE

To study the effects of ligustrazine on mechanical electricity in guinea pig ventricular papillary muscles and on contraction of pig coronary artery.

METHOD

Standard glass microelectrode technology; electrophysiological method; and blood vessel perfusion were used.

RESULT

1. ligustrazine(3-100 mumol/L) suppressed the action potential duration (APD) and the force of contraction (FC) of the fast action potentials (FAP), as well as the action potential amplitude (APA), APD, FC and the maximal upstroke velocity(Vmax) of the slow action potentials (SAP). 2. ligustrazine (3.0 mmol/L) induced SAP and contraction, but failed in beta-adrenoreceptor blocked muscles. Elevation of[Ca2+]o increased the action potential amplitude (APA). 3. ligustrazine(10(-5)-5 x 10(-3) mol/L) decreased the contractile response to high KCl in pig coronary artery.

CONCLUSION

Ligustrazine might affect the inward current of myocardial cells through beta-adrenoreceptor, and the diastolizing effect of ligustrazine on coronary artery might have nothing to do with the exciting beta-adrenoreceptor.