Biomedical subjects

Xin Zhou

Publications and source records attributed to Xin Zhou.

At least 109 records · Page 6Linked to original sources

PubMed2004

Novel synthetic route to octasubstituted naphthalenes from four alkynes and one olefin unit via zirconacyclopentadienes and 1,2-diiodo-3,4,5,6-tetraalkylbenzene.

1,2,3,4-Tetrasubstituted benzene derivatives were prepared by the reaction of zirconacyclopentadienes with vinyl bromide in the presence of NiCl(2)(PPh(3))(2). 1,2-Diiodo-3,4,5,6-tetraalkylbenzenes were formed by treatment of 1,2,3,4-tetraalkylbenzenes with iodine and periodic acid in the presence of a catalytic amount of sulfuric acid. Reaction of the 1,2-diiodo-3,4,5,6-tetraalkylbenzenes with zirconacyclopentadienes in the presence of a stoichiometric amount of CuCl gave sterically crowded octasubstituted naphthalenes in moderate yields.

Journal Article↗

PubMed2004

Calculations on the octupolar molecules with enhanced two-photon absorption cross sections based on the Zn (II) and Cu (I) as centers.

The equilibrium geometries, electronic structures, as well as one- and two-photon absorption cross sections of a series of octupolar chromophores with Zn(2+) or Cu(+) as coordinate centers and 4,4'-bis(dibutylaminostyryl)-[2,2']-bis(bipyridyl) as ligands have been determined by using B3LYP/6-31G and ZINDO methods. These molecules are designed by controlled combination of two or three bipyridyl ligands with the metal centers. The results show that Zn(2+) is an effective template for the design of octupolar structures which enable it to form tetrahedral and octahedral coordinated complexes; while Cu(+) only exists in a tetrahedral coordinated complex, comparing the tetrahedral complex with Zn(2+) as the center with that of Cu(+) as the center, it is found that the complex with the Cu(+) center is a better two-photon absorption material than the former as far as the transparency/nonlinearity is concerned. Furthermore, for the same metal center of Zn(2+), both one- and two-photon absorptions of the tetrahedral complex are redshifted relative to those of the octahedral complex, is attributed to the spiroconjugation effect in the tetrahedral complex. Our theoretical findings are consistent with recent experimental observations and provide an important foundation for the design of improved transparency-nonlinearity two-photon absorption materials.

Journal Article↗

PubMed2004

Sulfotransferase 1A1 (SULT1A1) polymorphism and breast cancer risk in Chinese women.

BACKGROUND: Sulfonation catalyzed by sulfotransferase enzymes plays an important role in chemical defense mechanisms against various xenobiotics but also bioactivates carcinogens. A major human sulfotransferase, SULT1A1, catalyzes the sulfation of a variety of phenolic and estrogenic compounds. A functional polymorphism of the SULT1A1 gene has been implicated in a decreased activity and thermostability when the wild-type arginine (Arg) at codon 213 is substituted by a histidine (His). METHODS: We investigated the association between the His allele and the risk breast cancer in 213 cases and 430 matched controls in Chinese women, and the interaction between His allele and endogenous estrogen and dietary mutagens exposure factors were also determined by use of logistic regression analysis. RESULTS: There was no significant difference in genotypes between the cancer patients and control populations. However, the frequency of the His allele in cases (13.6%) were significant higher than that in controls (9.5%), P = 0.03. Compared with women carrying the Arg/Arg genotype, the adjusted odds ratio (OR) of Arg/His was 1.48 (95% CI = 0.59-3.31) and His/His was 2.28 (95% CI = 0.69-9.58), P trend was 0.04. The adjusted OR of Arg/His + His/His was 2.60 (95% CI = 1.12-6.05). His allele strengthen the effect of endogenous estrogen exposure with interaction index r > 1, and weaken the effect of heterocyclic amines and polycyclic aromatic hydrocarbons derived from dietary with interaction index r > 1, both were multiplicative interaction model. CONCLUSIONS: Our findings suggest that the SULT1A1 His allele was positively associated with the risk of breast cancer in Chinese women. And there was interaction between SULT1A1 polymorphism and related exposure factors.

Adult↗

PubMed2004

[Interaction of ApoE and LDL-R gene polymorphisms and alcohol drinking and smoking on coronary heart disease].

OBJECTIVE: To investigate the association between the ApoE and LDLR-R gene loci on coronary heart disease (CHD) and their interaction with alcohol drinking and smoking in Hans of Chinese. METHODS: A questionnaire survey of the behaviors of smoking and drinking, dietary custom, and anamnesis, was conducted among 146 cases of CHD, aged 64 +/- 11, and 340 controls, aged 63 +/- 12. Peripheral blood samples were collected and the total DNAs were extracted. The levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were examined. The ApoE genotype was identified by the method of multiplex amplification refractory mutation system and AvaII polymorphisms of the LDL-R gene were detected by using the method of polymerase chain reaction-restriction fragment length polymorphism. The interaction between the genes and alcohol drinking and smoking was analyzed by using multivariate logistic regression models. RESULTS: (1) Both the systolic blood pressure and diastolic blood pressure of the CHD patients (132 mm Hg +/- 21 mm Hg, and 81 mm Hg +/- 13 mm Hg, 1 mm Hg = 0.133 kPa) were significantly higher than those of the controls (123 mm Hg +/- 17 mm Hg and 77 mm Hg +/- 11 mm Hg, both P < 0.05). The level of TG was 1.6 +/- 0.9 mmol/L in the CHD group, significantly higher than that in the control group (1.4 +/- 0.8 mmol/L, P < 0.05). However, there was no difference in the levels of TC, LDL-C, and HDL-C between the 2 groups (all P > 0.05). (2) For the ApoE gene, the frequencies of E4/3 genotype and epsilon 4 allele were 24.0% and 13.4% respectively in the CHD group, both significantly higher than those in the control group (12.9% and 7.2% respectively, both P < 0.05). For the LDLR-AvaII locus, no difference was found in different genotypes between the CHD and control groups. However, the proportion of those with epsilon 4 locus and AvaII(+) locus simultaneously was 60% in the CHD group, significantly higher than in the control group (31.8%, P < 0.05). (3) After adjustment of confounding variables, such as age, sex, blood pressure, and body mass index, the binary logistic analysis showed a significant gene-environment interaction (P < 0.05). The OR value were: for epsilon 4-AvaII(+): 2.99 (95% CI: 1.36 approximately 6.66, P < 0.01), for epsilon 3-often drinking: 2.60 (95% CI: 1.35 approximately 5.02, P < 0.01), for epsilon 3-smoking 2.58 (95% CI: 1.16 approximately 5.71, P < 0.05), for epsilon 4-stopped smoking 3.12 (95% CI: 1.23 approximately 8.09, P < 0.05), for epsilon 4-smoking: 5.30 (95% CI: 1.21 approximately 23.22, P < 0.05), and for AvaII(+)-often drinking: 2.49 (95% CI: 1.12 approximately 5.52, P < 0.05) respectively. CONCLUSION: The carriers of epsilon 3, epsilon 4 or AvaII(+) alleles would have higher risk of suffering from CHD if they are drink alcohol or smoke heavily.

Adult↗

PubMed2004

Orientational orders of small anisotropic molecules confined in slit pores.

Based on a constant-pressure Monte Carlo molecular simulation, we have studied orientationally ordered transitions of small anisotropic molecules confined in two parallel hard walls. These molecules are modeled by the hard Gaussian overlap model. The molecular elongations of the chosen molecules are so small that the molecules cannot form stable liquid-crystal (LC) phases in the bulk. But in the slit pores, we found, while the distance between two walls of the pores decreases to the molecular scale, an orientationally ordered phase can form. It shows that even hard confining surfaces favor the alignment of the small anisotropic molecules. Thus we conclude that the required molecular elongation for forming LC phases will decrease in confinement. Our results indicate that some non-LC small molecules may form stable LC phases due to the inducement of confining surfaces.

Journal Article↗

PubMed2004

Orientational order in binary mixtures of hard Gaussian overlap molecules.

Based on a standard constant-pressure Monte Carlo molecular simulation, we have studied liquid crystal phases of binary mixtures of nonspherical molecules. The components of the mixtures are two types of hard Gaussian overlap (HGO) molecules. The first type of molecule has a small molecularelongation parameter (short HGO molecules) and cannot form stable liquid crystal phase in the bulk by themselves. The second type of molecule has a large elongation parameter (long HGO molecules) and can form a liquid crystal phase easily. In the mixtures, the short HGO molecules can form an orientationally ordered phase because the long HGO molecules form confining surfaces to induce the alignment of the short molecules. We also study the isotropic-nematic phase transition in different mixtures composed of short and long HGO molecules with different elongations and concentrations. The obtained result implies that small anisotropic molecules can show liquid crystal behavior.

Journal Article↗

PubMed2004

Blood lead levels of both mothers and their newborn infants in the middle part of China.

A cross-sectional investigation on maternal and umbilical blood lead levels in an urban area, an industrial town and a rural area of middle China is reported. Blood samples from 89 mothers during delivery, from the umbilical cords and from 105 non-pregnant women were collected. Self-administered questionnaires including the medical history and the pregnancy-related complaints were performed. After acid digestion, the whole blood lead levels were determined by a 180-80 flame atomic absorption spectrometer. The geometric mean for lead levels in blood of non-pregnant women was 66.9 microg/l (range: 25.0-201.0 microg/l) in the urban, 66.9 microg/l (range: 30.5-198.8 microg/l) in the industrial town, and 53.3 microg/l (range: 16.0-170.5 microg/l) in the rural area. The geometric mean of lead levels in blood of pregnant women at delivery both in the rural area (74.4 microg/l, range: 35.2-245.6 microg/l) and industrial town (65.9 micro/l, range: 20.0-172.0 microg/l) were higher than in the urban region (54.3 microg/l, range: 27.9-187.0 microg/l; p < 0.05). Compared with non-pregnant women at the same area, the blood lead levels of pregnant women was lower in urban (p < 0.05), but higher in rural areas (p < 0.05). The geometric mean for lead level in umbilical cord blood was significantly higher in rural (84.1 microg/l, range: 28.0-185.0 microg/l) than in the other areas (53.5 microg/l, range: 23.5-156.7 microg/l in the urban; 60.1 microg/l, range: 12.5-168.3 microg/l in the industrial town). The total geometric mean for lead level in cord blood was 69.0 microg/l (range: 12.5-185.0 microg/l), and 17.8% samples were above the blood lead threshold of health concern (> or =100 microg/l) for children (CDC, 1991), but the body weight and length of newborn babies have not been affected. The correlation between maternal and cord blood was 0.6805 (p < 0.01). Most of the pregnant women did not take the calcium supplements recommended during pregnancy. In conclusion, there were some lead burdens on both the mothers and their newborn babies in these areas. All possible measures should be taken to reduce the environmental lead exposure. It is also crucial that maternal nutrient intake, particularly calcium, should be sufficient.

Adult↗

PubMed2004

Development of an unbiased method for the estimation of liver steatosis.

BACKGROUND: Steatosis significantly contributes to an organ's transplantability. Livers with >30% fat content have a 25% chance of developing primary non-function (PNF). The current practice of evaluating a hematoxylin and eosin (H&E) stained donor biopsy by visual interpretation is subjective. We hypothesized that H&E staining of frozen sections fails to accurately estimate the degree of steatosis present within a given liver biopsy. To address this problem of evaluating steatosis in prospective donor organs, we developed a fast, user friendly computer methodology to objectively assess fat content based on the differential quantification of color pixels in Oil Red O (ORO) stained liver biopsies. METHODS: The accuracy of human visual estimation of fat content by H&E and ORO stains was compared with computer-based measurements of the same slides from 25 frozen sections of donor biopsies. RESULTS: Samples with a fat content >20% showed marked variation between human interpretation and computer analysis. There was also a significant difference in the human interpretation of fat based on the method of staining. This difference ranged from 3 to 37% with H&E. DISCUSSION: Use of ORO resulted in a more consistent estimation of liver steatosis compared with H&E, but human interpretations failed to correlate with computer measurements. Such differences in fat content estimations might result in the rejection of a potentially transplantable organ or the acceptance of a marginal one. Ideally, our protocol can rapidly be applied to clinical practice for accurate and consistent measurement of fat in liver sections for the ultimate purpose of increasing the number of successful transplantable organs.

Algorithms↗

PubMed2004

Induction of interleukin-8 in T84 cells by Vibrio cholerae.

The induction of interleukin-8 (IL-8) in vitro has been suggested to correlate with the reactogenicity of Vibrio cholerae vaccine candidates. V. cholerae vaccine candidate 638, a hemagglutinin protease/hap-defective strain, was recently reported to be well tolerated in human volunteers, suggesting a role for Hap in reactogenicity. We examined the role of hap in the induction of IL-8 in intestinal epithelial T84 cells. Wild-type V. cholerae strains 3038 and C7258 and a vaccine candidate strain, JBK70, induced levels of IL-8 similar to those of their isogenic hap mutants. Supernatant containing Hap did not stimulate IL-8 production at a variety of concentrations tested, suggesting that Hap itself does not induce IL-8 production. Furthermore, supernatant from CVD115, which had deletions of hap and rtxA (encoding repeats in toxin) and was derived from a reactogenic strain, CVD110, induced IL-8 production in T84 cells in a dose-dependent manner. The IL-8-stimulating activity of CVD115 culture supernatants was growth phase dependent and was strongest in stationary phase cultures. This IL-8 stimulator(s) was resistant to heat treatment but sensitive to proteinase. Protease activity in vitro did not correlate with the reactogenicity of V. cholerae vaccine candidates. Our data suggest that Hap is not an IL-8 inducer in T84 cells and that the IL-8 stimulator in the supernatant of V. cholerae culture may play a role in reactogenicity.

Cholera Vaccines↗

PubMed2004

Transcriptional responses of intestinal epithelial cells to infection with Vibrio cholerae.

Vibrio cholerae is a noninvasive enteric bacterium that causes the severe diarrheal disease cholera. Candidate cholera vaccines have been engineered by deleting genes encoding known virulence factors in V. cholerae; however, many of these attenuated strains were still reactogenic in human volunteers. In this study, DNA arrays were utilized to monitor the transcriptional responses of human intestinal epithelial cells (T84) to eight strains of V. cholerae, including attenuated, toxigenic, and environmental isolates. cDNA probes generated from host RNA samples were hybridized against low- and high-density gene arrays. V. cholerae induced the transcription of a variety of host genes and repressed the expression of a lower number of genes. Expression patterns were confirmed for certain genes by reverse transcriptase PCR and enzyme-linked immunosorbent assays. A core subset of genes was found to be differentially regulated in all experiments. These genes included genes involved in innate mucosal immunity, intracellular signaling, and cellular proliferation. Reactogenic vaccine strains induced greater expression of genes for certain proinflammatory cytokines than nonreactogenic strains. Wild-type and attenuated derivatives induced and repressed many genes in common, although there were differences in the transcription profiles. These results indicate that the types of host genes modulated by attenuated V. cholerae, and the extent of their induction, may mediate the symptoms seen with reactogenic cholera vaccine strains.

Chemokines↗

PubMed2004

Evaluation of the functional involvement of human immunodeficiency virus type 1 integrase in nuclear import of viral cDNA during acute infection.

Nuclear import of viral cDNA is a critical step for establishing the proviral state of human immunodeficiency virus type 1 (HIV-1). The contribution of HIV-1 integrase (IN) to the nuclear import of viral cDNA is controversial, partly due to a lack of identification of its bona fide nuclear localization signal. In this study, to address this putative function of HIV-1 IN, the effects of mutations at key residues for viral cDNA recognition (PYNP at positions 142 to 145, K156, K159, and K160) were evaluated in the context of viral replication. During acute infection, some mutations (N144Q, PYNP>KL, and KKK>AAA) severely reduced viral gene expression to less than 1% the wild-type (WT) level. None of the mutations affected the synthesis of viral cDNA. Meanwhile, the levels of integrated viral cDNA produced by N144Q, PYNP>KL, and KKK>AAA mutants were severely reduced to less than 1% the WT level. Quantitative PCR analysis of viral cDNA in nuclei and fluorescence in situ hybridization analysis showed that these mutations significantly reduced the level of viral cDNA accumulation in nuclei. Further analysis revealed that IN proteins carrying the N144Q, PYNP>KL, and KKK>AAA mutations showed severely reduced binding to viral cDNA but kept their karyophilic properties. Taken together, these results indicate that mutations that reduced the binding of IN to viral cDNA resulted in severe impairment of virus infectivity, most likely by affecting the nuclear import of viral cDNA that proceeds integration. These results suggest that HIV-1 IN may be one of the critical constituents for the efficient nuclear import of viral cDNA.

Active Transport, Cell Nucleus↗

PubMed2004

[A case-control study on the risk of female breast cancer in Wuhan area].

OBJECTIVE: To investigate the risk factors of female breast cancer and its potential alteration in Wuhan area. METHODS: A case-control study was conducted on 213 cases with histopathological diagnosis and 430 matched controls, using conditional logistic regression analysis. RESULTS: 28 factors such as educational level, history of benign breast disease, age at menarche, age at menopausal, meat and well-done meat intake, soy bean food, fruit, lactation time, body mass index (BMI), juvenile chest X-ray, psychological factor, were associated with breast cancer risk in one-way variance model. Multivariate conditional logistic regression analysis in total significant factors and subgroups showed that the risk factors of breast cancer would include high level education, psychological trauma, history of benign breast disease later age at menopause, more years of menstrual and more years of menstrual before giving first birth, high BMI, well-done meat intake and smoked food. Factors as later menarche, lactate longer, soybean food, fruit, drink tea habit were protective factors for breast cancer. Further breakdown of data showed some difference between premenopausal and postmenopausal women. Risks in premenopausal women were associated with history of benign breast disease, age of menarche, soybean food intake, whereas risks in postmenopausal women were related to age of menopausal, BMI, waist-hip ratio and fruit intake. Both psychological traumatic and duration of lactation were common pre-and postmenopausal risk and protective factors. CONCLUSIONS: Dietary habit and endogenous estrogen exposure related factors played important roles on women breast cancer in Wuhan area.

Adult↗

PubMed2004

[Influence of salbutamol inhalation during volume target pressure control ventilation on ventilation parameters in patients with respiratory failure].

OBJECTIVE: To compare the effects of volume target pressure control ventilation (VTPC) and volume control ventilation (VCV) on respiratory mechanics in patients with respiratory failure, and to investigate the effects of ventilated parameters after salbutamol inhalation. METHODS: Ten patients with mean age (68+/-5) years were intubated and mechanically ventilated for acute respiratory failure of diverse causes. After 30 minutes with VCV [tidal volume (VT) 8-10 ml/kg], measurements of respiratory mechanics were begun, and then the patients were ventilated with VTPC for 30 minutes. VCV and VTPC were repeated after salbutamol 600 microg inhalation. RESULTS: The static compliance (Cst) was (38.4+/-2.7) ml/cm H2O (1 cm H2O=0.098 kPa) and airway resistance (Raw) was (20.1+/-2.0) cm H2O x L(-1) x s(-1) in 10 patients. With the same tidal volume, peak inspiratory pressure (PIP) and mean inspiratory flow [VT/inflation time (Tinflate)]during VTPC were lower, but peak inspiratory flow (PIF) was significantly higher than that during VCV (all P<0.05). The same plateau pressure (Pplat) was observed during VCV as during VTPC, they were (22.1+/-0.9) cm H2O vs. (23.0+/-1.2) cm H2O. After salbutamol inhalation, PIP and Raw were significantly decreased in all patients (both P<0.05), but no changes were found in Cst and Pplat. PIF and peak expiratory flow (PEF) were increased much more during two modes than before inhalation (both P<0.05), but Tinflate was decreased (P<0.05). CONCLUSION: VTPC is a new mechanical ventilation mode in which closed-loop control theory is used. The airway pressure during VTPC is associated with Cst and not influenced by Raw.

Administration, Inhalation↗

PubMed2004

[Inhibition of human lung fibroblast proliferation and the mitogen activated protein kinase pathway by dexamethasone].

OBJECTIVE: To investigate the effects of dexamethasone on human lung fibroblast cell proliferation, cell cycles, and cell mitogen-activated protein kinases (MAPKs) passway. METHODS: Dexamethasone was used at various concentration in culture medium. Cell number was counted using a hemacytometer. Whole cell propidium iodide staining and flow cytometric analysis were performed to determine cellular DNA content. MAPK proteins and activation were tested by Western blot analysis with antibodies to c-Jun N-terminal kinase (JNK), phospho-JNK, extracellular signal-regulated kinase (ERK), phospho-ERK, p38 and phospho-p38. RESULTS: 1x10(-7) mol/L and 1x10(-6) mol/L dexamethasone suppressed the proliferation of lung fibroblast cells by 34% and 72%, respectively, than that of control. This suppression was dose-dependant. Dexamethasone suppressed cell cycle with accumulation of cells in G1/G0 stage. It increased from 81.9% to 90.1% compared with that of control. We did not find any apoptosis induced by dexamethasone for lung fibroblast cells. Using Western blot analysis, we found that dexamethasone resulted in decreased activity of ERK, but had no effects on JNK and p38. CONCLUSIONS: Dexamethasone may suppresses the proliferation of lung fibroblast cells, which is partly resulted from the facts that it can inhibit ERK activation in MAPK-signaling pathway but has little effect on JNK and p38 pathway. Dexamethasone may not induce lung fibroblast cell apoptosis directly.

Cell Cycle↗

PubMed2004

Expression of survivin mRNA in peritoneal lavage fluid from patients with gastric carcinoma.

BACKGROUND: Peritoneal dissemination is the most common pattern of metastasis in advanced gastric carcinoma with serosal invasion. In the present study, we reported the clinical relevance of a new diagnostic method involving RT-PCR, using survivin as the target gene, for the detection of free cancer cells in peritoneal washes. METHODS: Intraoperative peritoneal washes were obtained from 48 patients who underwent surgery for gastric cancer. RT-PCR analysis with primers specific for survivin and conventional cytological examinations were both performed. RESULTS: Survivin mRNA was not detected in any peritoneal wash samples from patients with benign disease, but was detected in 28 of 48 samples taken from patients with gastric cancer and in all metastatic nodules. Survivin expression in the peritoneal cavity significantly correlated with depth of cancer invasion, lymph node metastasis, and TNM stage. There were 92% of clinically evident peritoneal metastasis cases showed detectable survivin expression. The combination of survivin RT-PCR and cytological examination yielded positive results in 66.7% (32/48) of patients with gastric cancer, much higher than the results produced by cytological method alone. CONCLUSIONS: Survivin mRNA detected in peritoneal lavage fluid might indicate the presence of free cancer cells in the peritoneal cavity. The high sensitivity of the RT-PCR-based survivin assay suggests that survivin serves as a molecular marker for detecting peritoneal micrometastasis. Its ubiquitous expression in peritoneal cancer cells and metastatic nodules also suggests a promising future therapeutic strategy based on survivin inhibition for cases of gastric cancer involving peritoneal metastasis.

Adult↗

PubMed2004

[Influence of mixed grafting of autologous and allogeneic microskin on burn wound healing in rats].

OBJECTIVE: To observe the influence of mixed grafting of autologous and allogeneic microskin on burn wound healing. METHODS: Autologous microskin grafting (expansion rate 5:1) was employed as control. Autologous microskin mixed with the allogeneic microskin with the thickness of 0.3 mm and 0.6 mm, respectively, were designated as experimental groups 1 and 2 (EP1 and EP2). The wound healing rate, wound contraction rate, and histological changes were observed on the 2nd, 3rd and 4th weeks after the grafting. RESULTS: The wound healing rate in two experimental groups (94.58 +/- 3.99)% in EP1, and (95.28 +/- 1.93)% in EP2 was significantly higher than that in the control group (88.28 +/- 6.85)% at the end of the 2nd week after the grafting (P < 0.05) The wound healing rate in experimental group 2 (94.55 +/- 3.47)% was obviously higher than that in control (88.51 +/- 5.59)% and experimental group 1 (89.51 +/- 4.70)% at the end of the 3rd week after grafting (P < 0.05). There was no obvious difference in wound healing rate among the three groups at the end of the 4th week after grafting. Obvious lymphocytic infiltration was observed by histological examination between epidermis and dermis in the two experimental groups at the end of the 2nd week after grafting. But there was no obvious difference among the three groups 4 weeks after grafting. CONCLUSION: The wound healing could be improved by mixed skin grafting with appropriate quantity of allogeneic and autologous microskin. Furthermore, the wound contraction could be ameliorated if the thickness of allogeneic dermis was increased in the mixed grafting even with the same proportion of allogeneic to autologous microskin.

Animals↗

PubMed2004

[The dynamic changes of collagen fiber in quartz-induced pulmonary fibrosis in mice with picrosirius red plus polarized microscopy in vivo].

OBJECTIVE: To investigate the use value of picrosirius red staining plus polarized microscopy to observe the dynamic changes of collagen fiber in lung fibrosis in silicotic mice model. METHODS: The experimental mice were divided into control and quartz groups. 0.2 g/kg weight of quartz was injected intratracheally in quartz group. Lung tissues were collected at the 1st, 3rd, 5th, 7th, 14th and 28th day after injection respectively. Lung tissue slides were stained with picrosirius red. With the aid of polarized microscope, image analysis software, the distribution and change of type I and type III collagen could be qualitatively and quantitatively analyzed. Lung tissue hydroxyproline was determined by chloramines T method. RESULTS: In early stage the predominant increment was type III collagen, but in late stage type I was predominant. The contents of both type collagen tended to increase as postexposure time prolonged. The time course of the ratio of type I to type III showed increasing trend, and there was a statistical significance on day 28 (1.49 +/- 0.39 vs 0.59 +/- 0.24, P < 0.05). The total area of collagen was positively correlated with hydroxyproline concentration of lung tissue (r(2) = 0.928 5, P < 0.01). CONCLUSION: Picrosirius red staining combined with polarized microscopy and digital image processing is a useful method to elucidate collagen accumulation, distribution and subtype ratio in silicosis.

Animals↗

PubMed2004

Effect of peroxisome proliferator-activated receptor activators on tumor necrosis factor-alpha expression in neonatal rat cardiac myocytes.

OBJECTIVE: To investigate the effect of peroxisome proliferator-activated receptor-alpha (PPAR alpha) and PPAR gamma activators on tumor necrosis factor-alpha (TNFalpha) expression in neonatal rat cardiac myocytes. METHODS: Primary cultures of cardiac myocytes from 1- to 3-day-old Wistar rats were prepared, and myocytes were exposed to lipopolysaccharide (LPS) and varying concentrations of PPAR alpha or PPAR gamma activator (fenofibrate or pioglitazone). RT-PCR and ELISA were used to measure TNFalpha, PPAR alpha, and PPAR gamma expression in cultured cardiac myocytes. Transient transfection of TNFalpha promoter with or without nuclear factor-kappaB (NF-kappaB) binding site to cardiac myocytes was performed. RESULTS: Pretreatment of cardiac myocytes with fenofibrate or pioglitazone inhibited LPS-induced TNFalpha mRNA and protein expression in a dose-dependent manner. However, no significant changes were observed on PPAR alpha or PPAR gamma mRNA expression when cardiac myocytes were pretreated with fenofibrate or pioglitazone. Proportional suppression of TNFalpha promoter activity was observed when myocytes was transiently transfected with whole length of TNFalpha promoter (-721/+17) after being stimulated with LPS and fenofibrate or pioglitazone, whereas no change of promoter activity was observed with transfection of TNFalpha reporter construct in deletion of NF-kappaB binding site (-182/+17). CONCLUSIONS: PPAR alpha and PPAR gamma activators may inhibit cardiac TNFalpha expression but not accompanied by change of PPAR alpha or PPAR gamma mRNA expression. Therefore PPAR alpha and PPAR gamma activators appear to play a role in anti-inflammation. The mechanism may partly be involved in suppression of the NF-kappaB pathway.

Animals↗