The beneficial effect of Radix Dipsaci total saponins on bone metabolism in vitro and in vivo and the possible mechanisms of action

The purpose of this study is to investigate the anti-osteoporotic effects of Radix Dipsaci total saponins (RTS). We showed that RTS was able to improve bone properties by either an increase of osteoblastic activity or a decrease in osteoclastic activity.

INTRODUCTION

Radix Dipsaci has long been used as an anti-osteoporotic drug. The present study investigates the anti-osteoporotic effects of RTS.

METHODS

Three-month-old female rats were randomly assigned into a sham-operated group (sham) and five ovariectomy (OVX) subgroups, namely, OVX with vehicle (OVX), OVX with 17β-ethinylestradiol (E(2)), and OVX with graded doses of RTS (50, 100, or 200 mg/kg/d). RTS and E(2) were administered orally, daily from 1 week after OVX treatment for 4 months. Bone mass, turnover, and strength were evaluated by dual-energy X-ray absorptiometry, biochemical markers, and the three-point bending test. The trabecular bone microarchitecture was assessed by microCT. In vitro experiments were performed to determine the potential molecular mechanisms of the anti-osteoporotic effect of RTS.

RESULTS

RTS prevented the loss of bone mass induced by OVX. The preventive effect on bone loss was primarily indicated by decreasing levels of bone turnover markers and confirmed by the changes in urinary calcium and phosphorus excretion. The treatment also enhanced the biomechanical strength of bone and prevented the deterioration of trabecular bone microarchitecture. RTS induced MC3T3-E1 and primary osteoblastic cell maturation and differentiation and increased bone formation by increasing BMP-2 synthesis. In addition, RTS inhibited osteoclastogenesis through an increase in osteoprotegrin and a decrease in NF-kB ligand expression in vitro.

CONCLUSIONS

RTS treatment can effectively suppress the loss of bone mass induced by OVX and in vitro evidence suggests this could be through actions on both osteoblasts and osteoclasts.

Reduction of blood loss from diagnostic sampling in critically ill patients using a blood-conserving arterial line system

STUDY OBJECTIVE

To demonstrate the utility of a new blood-conserving arterial line system in reducing blood loss associated with blood drawing in the critical care setting.

DESIGN

Prospective, randomized, crossover comparison between two arterial line systems.

SETTING

Medical intensive care unit (ICU); tertiary care teaching institution.

PATIENTS

Thirty-one patients who required invasive arterial blood pressure monitoring throughout their ICU course.

INTERVENTIONS

For ICU days 1 to 2, patients were randomized to receive either a conventional arterial line system or a new blood-conserving arterial line system. On ICU days 3 to 7, patients with a conventional arterial line were crossed over to the blood-conserving arterial line, and vice versa. Laboratory blood volumes, mixed discard volumes, and blood discard volumes were then recorded to document how much blood loss is associated with each aspect of the blood sampling process.

RESULTS

The mean total volume of blood sent to the laboratory for testing was 257.4 ml. As a result of "clearing the line" over the 7-day period, patients with the conventional arterial line system lost a mean volume of 340.2 ml of blood mixed with heparinized saline solution more than patients with the blood-conserving arterial line. In terms of the blood component of the blood-heparinized saline solution mixture, use of the conventional arterial line was associated with an average of 156.8 ml more blood discarded than with the blood-conserving arterial line.

CONCLUSION

The new blood-conserving arterial line system provides a simple and effective method for reducing blood loss related to diagnostic sampling in the critical care setting.

Clinical implications of left atrial appendage flow patterns in nonrheumatic atrial fibrillation

Left atrial appendage (LAA) function and flow patterns in 29 patients with chronic nonrheumatic atrial fibrillation were studied by transesophageal echocardiography. These 29 patients (16 men and 13 women; mean age, 63.8 years; range, 38 to 77 years) were classified into two groups according to different LAA flow patterns. Seventeen patients (group 1) had well-defined LAA emptying and filling Doppler flow signals, and the other 12 patients (group 2) had very low LAA flow signals. No significant differences were found in age, sex, mean duration of atrial fibrillation, left ventricular end diastolic dimension, and left ventricular ejection fraction between the two groups. However, group 2 patients had larger left atrial diameter (42.8 +/- 4.2 mm vs 36.6 +/- 8.8 mm; p < 0.05), lower LAA ejection fraction (26.4 +/- 15.2 percent vs 42.6 +/- 14.1 percent; p < 0.05), and lower LAA peak emptying velocity (0.13 +/- 0.03 m/s vs 0.36 +/- 0.16 m/s; p < 0.001). Higher incidence of LAA spontaneous echocardiographic contrast formation in group 2 patients (8/12 vs 1/17; p < 0.001) was noted. In conclusion, a subset of patients with nonrheumatic atrial fibrillation were found to have lower LAA blood flow and poorer LAA function. These patients had higher incidence of left atrial or LAA spontaneous echo contrast formation which had been proved previously to be a marker for future systemic thromboembolism.

Characteristics of accumulation of oral gram-positive bacteria on mucin-conditioned glass surfaces in a model system

Strains of Streptococcus, Actinomyces and Lactobacillus were grown on glass surfaces in semi-defined medium (pH 7.0) with mucin, at a dilution rate of D = 0.1 h-1, in a modified chemostat. The accumulation of cells followed four phases. In phase 1 (0-1 h), cells did not divide on the surfaces and adhesion accounted for rapid accumulation. Phase 2 (1-4 h) comprised adhesion and cell division, and accumulation slowed, cell number doubling times (Cdt) Streptococcus, 2.7 h to 8.6 h, Actinomyces, 2.3 h to 7.5 h and Lactobacillus, 3.6 h to 3.8 h. Cell division on surfaces accounted for accumulation in phase 3 (4 h to 12 h): Cdt Streptococcus, 1.7 h to 5.2 h, Actinomyces, 2.4 h to 7.5 h and Lactobacillus, 2.2 h to 7.2 h. The biofilm stabilized in Phase 4, Cdt 18.5 h to 90.2 h. The numbers (10(6) colony-forming units per cm2) of cells in stable biofilms were Streptococcus, 4.02 to 5.12, Actinomyces, 12.5 and 34.0 and Lactobacillus, 2.77. Accumulation increased (Cdt 0.9 h-2.7 h) when cells were exposed to glucose excess or high dilution rates and phase 2 of accumulation did not occur.

Clinical implications and factors related to left atrial spontaneous echo contrast in chronic nonvalvular atrial fibrillation

The mechanisms leading to formation of spontaneous echo contrast (SEC), a smoke-like echo on echocardiography, are still controversial. To further explore the clinical implications and factors related to SEC formation, the correlation among echocardiographic variables, hematologic parameters or platelet aggregability, and the occurrence of SEC was studied in 119 patients with chronic nonvalvular atrial fibrillation. There were 75 men and 44 women with a mean age of 65 +/- 10 years (range 38-88). Left atrial SEC was detected in 39 patients (33%) by transesophageal echocardiography. Patients with history of systemic embolism were more frequently found to have left atrial SEC and left atrial thrombus by univariate analysis. Multivariate analysis showed that left atrial SEC (p < 0.001) was the only independent predictor of history of systemic embolism. Age, sex, left atrial or left ventricular dimension, left ventricular ejection fraction, antiplatelet or anticoagulant therapy and the percentage of lone atrial fibrillation were not significantly different between patients with and without left atrial SEC. Among the hematologic parameters, higher hematocrit was found in patients with left atrial SEC, while white blood cell and platelet counts were comparable in both groups. Platelet aggregability with different concentrations of inducers, adenosine diphosphate and collagen, was evaluated by the turbidimetric method in 15 patients with left atrial SEC and in 42 patients without left atrial SEC who were not receiving antiplatelet or anticoagulant therapy. No significant difference was found in platelet aggregability using four inducer concentrations between two groups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

In vivo and in vitro modulation of intercellular adhesion molecule (ICAM)-1 expression by hypertonicity

Hepatic ischemia-reperfusion (I/R) is an important cause of organ dysfunction in the critically ill. With reperfusion, Kupffer cells release pro-inflammatory cytokines that promote endothelial cell (EC) expression of adhesion molecules such as intercellular adhesion molecule (ICAM)-1, facilitating neutrophil (PMN) infiltration. Studies suggest hypertonic saline (HTS) might exert beneficial effects on development of organ injury following shock on the basis of reduced PMN-EC interactions. We hypothesized that HTS alters expression of EC ICAM-1 and thus minimizes PMN-mediated injury. To test our hypothesis, we used an in vivo model of hepatic I/R and an in vitro model of activated EC. Rats underwent 30 min of hepatic ischemia after pretreatment with HTS (7.5% NaCl, 4cc/kg ia) or normal saline (NS). At 4 h reperfusion, plasma was taken for aspartate aminotransferase (AST) and liver tissue was harvested for assessment of hepatic ICAM-1 mRNA by Northern blot analysis. Human umbilical vein endothelial cells (HUVECs) were activated by lipopolysaccharide (LPS) and exposed to hypertonic medium (350-500 mOsM). HUVEC ICAM-1 protein was measured by cell ELISA and ICAM-1 mRNA by Northern blot analysis. HTS prevented hepatic I/R injury as measured by AST. AST of shams was 282.6+/-38.1 IU/L. I/R following NS pretreatment caused significant injury (AST 973.8+/-110.9 IU/L) compared to sham (SM) (P < 0.001). Pretreatment with HTS exerted significant protection following I/R with an AST of 450.9+/-56.3 IU/L (P < 0.05). There was no significant difference in AST levels between SM and HTS groups. Reduced hepatic injury after HTS and I/R was accompanied by inhibition of I/R-induced hepatic ICAM-1 mRNA expression compared to NS treated animals (P < 0.01). Similarly, hypertonicity inhibited HUVEC LPS-induced ICAM-1 protein (LPS: 1.86+/-0.19 absorbance units; 400 mOsM +/- LPS: 1.45+/-0.14 absorbance units; 450 mOsM + LPS: 1.02+/-0.19 absorbance units, P < 0.001) and mRNA expression. Thus, hypertonicity modulates endothelial ICAM-1 expression as one possible protective mechanism against I/R injury.

Physiological levels of beta-amyloid increase tyrosine phosphorylation and cytosolic calcium

The a beta peptide is a neurotoxic peptide that accumulates in the brains of Alzheimer patients, but is also present in body fluids at subnanomolar levels. The potential effects of these low levels of a beta are unclear. We now show that one such action is to increase tyrosine phosphorylation in PC12 cells and olfactory neuroblasts. Application of a beta 25-35 or a beta 1-40 induces a dose-dependent increase in the tyrosine phosphorylation in both whole cells and in vitro. The increase in tyrosine phosphorylation is both rapid and sensitive, being stimulated by picomolar doses of a beta and occurring within 1 min of application. Calcium imaging experiments provide further support for the role of tyrosine phosphorylation in the action of a beta. While a beta does not alter calcium metabolism under basal conditions, the addition of a beta induces a rapid increase in cytoplasmic calcium in olfactory neuroblasts that have been treated with the tyrosine phosphatase inhibitor, sodium orthovanadate or in PC12 cells treated with nerve growth factor. These responses could be blocked by the tyrosine kinase inhibitor, herbimycin. These calcium responses displayed an obligate requirement for the presence of matrix proteins. The identification of a rapid, sensitive assay for the action of a beta may facilitate investigations of its mechanism of action.

Substance P modulates human immunodeficiency virus replication in human peripheral blood monocyte-derived macrophages

Substance P (SP), a member of the tachykinin family of neuropeptides, is an important immunomodulator of lymphocyte and monocyte/macrophage function. We have examined the effects of SP on human immunodeficiency virus type 1 (HIV-1) infection of peripheral blood monocyte-derived macrophages (MDMs) in vitro. Human monocytes isolated by Ficoll gradient followed by adherence were maintained in vitro for 10 days and infected with HIV-1. The addition of SP resulted in a 2- to 8-fold-enhanced HIV-1 expression in the MDMs isolated from 7 of 13 healthy donors as determined by reverse transcriptase (RT) activity and p24 protein expression assays, as compared to control cultures incubated with HIV-1 alone. There was no correlation observed, however, between SP-stimulated TNF production and HIV-1 expression in MDMs obtained from a subset of these donors. These effects of SP on HIV-1 expression in MDMs in vitro may have in vivo implications relevant to modulation of monocyte/macrophage functions, to HIV-1 infection of monocytes/macrophages, and to the immunopathogenesis of HIV-1 infection.

Regulation of urease gene expression by Streptococcus salivarius growing in biofilms

The metabolism of urea by urease enzymes of oral bacteria profoundly influences oral biofilm pH homeostasis and oral microbial ecology. The purpose of this study was to gain insight into the regulation of expression of the low pH-inducible urease genes in populations of Streptococcus salivarius growing in vitro in biofilms and to explore whether urease regulation or the levels of urease expression in biofilm cells differed significantly from planktonic cells. Two strains of S. salivarius harbouring urease promoter fusions to a chloramphenicol acetyltransferase (cat) gene were used: PurelCAT, containing a fusion to the full-length, pH-sensitive promoter; or Pureldelta100CAT, a constitutively derepressed deletion derivative of the urease gene promoter. The strains were grown in a Rototorque biofilm reactor in a tryptone-yeast extract-sucrose medium with or without pH control. Both CAT and urease activities in biofilms were measured at 'quasi-steady state' and after a 25mM glucose pulse. The results showed that CAT expression in PurelCAT was repressed at relatively neutral pH values, and that expression could be induced by acidic pH after carbohydrate challenge. Biofilms of PurelCAT grown at low pH, without buffering, had about 20-fold higher CAT levels, and only a modest further induction could be elicited with carbohydrate pulsing. The levels of CAT in biofilms of PurelCAT grown in buffered medium were slightly higher than those reported for planktonic cells cultured at pH 7.0, and the levels of CAT in Purel-CAT growing at low pH or after induction were similar to those reported for fully induced planktonic cells. CAT activity in Pureldelta100CAT was constitutively high, regardless of growth conditions. Interestingly, urease activity detected in biofilms of the parent strain, S. salivarius 57.1, could be as much as 130-fold higher than that reported for fluid chemostat cultures grown under similar conditions. The higher level of urease activity in biofilms was probably caused by the accumulation of the stable urease enzyme within biofilm cells, low pH microenvironments and the growth phase of populations of cells in the biofilm. The ability of S. salivarius biofilm cells to upregulate urease expression in response to pH gradients and to accumulate greater quantities of urease enzyme when growing in biofilms may have a significant impact on oral biofilm pH homeostasis and microbial ecology in vivo. Additionally, S. salivarius carrying the pH-sensitive urease gene promoter fused to an appropriate reporter gene may be a useful biological probe for sensing biofilm pH in situ.

Low-protein diet improves meat quality of growing and finishing pigs through changing lipid metabolism, fiber characteristics, and free amino acid profile of the muscle

The objective of the study was to investigate the effect of feeding reduced CP, AA-supplemented diets on meat quality in growing and finishing pigs as well as the related mechanism. In experiment 1, 18 growing pigs (36.5 kg BW) were assigned randomly and fed 1 of 3 corn-soybean meal diets containing either 18% CP (normal protein, NP), 15% CP (low protein, LP), or 12% CP (very low protein, VLP). In experiment 2, 18 finishing pigs (62.3 kg BW) were allotted randomly into 1 of the following diets: 16% CP (NP), 13% CP (LP), or 10% CP (VLP). In both experiments, the LP and VLP diets were supplemented with crystalline AA to achieve equal content of standardized ileal digestible lysine, methionine, threonine, and tryptophan. At the end of each experiment, all pigs were slaughtered to collect longissimus dorsi muscle (LM) samples. Samples were used for determining meat quality, intramuscular fat (IMF) content, fatty acid composition, free AA profile, and expression of genes for myosin heavy chain isoforms. Results showed that growing and finishing pigs fed the LP diets increased (P < 0.05) redness value of LM, while finishing pigs fed the LP and VLP diets decreased (P < 0.05) the shear force values. Compared with the NP diet, growing and finishing pigs fed lower CP diets had higher (P < 0.05) contents of IMF and MUFA, and lower (P < 0.05) contents of PUFA. Besides, higher (P < 0.05) expression levels of type I and/or IIa muscle fibers were observed in LP diet-fed growing and finishing pigs, and greater concentrations of taurine and tasty AA in VLP diet-fed growing and finishing pigs. Taken together, our results indicate that low-protein diets could positively affect meat quality of growing and finishing pigs, and likely through regulation of IMF content and fatty acid composition, fiber characteristics, and free AA profile in the muscle.

G-33A mutation in the promoter region of thrombomodulin gene and its association with coronary artery disease and plasma soluble thrombomodulin levels

Thrombomodulin is an endothelial glycoprotein that decreases thrombin activity and activates protein C. A recent study has shown that G-33A promoter mutation of the thrombomodulin gene occurs particularly in Asians. In this study, we analyzed the distribution of G-33A mutation in the promoter region of the thrombomodulin gene in the Chinese population and determined whether the mutation might be a risk for coronary artery disease (CAD). In addition, the influence of this mutation on plasma soluble thrombomodulin levels in patients with CAD was also examined. We studied 320 consecutive patients (mean age 63 years; 73% men) with CAD and 200 age- and sex-matched control subjects. Screening for thrombomodulin G-33A promoter mutation was conducted using polymerase chain reaction, single-strand conformation polymorphism, and direct deoxyribonucleic acid sequencing. The frequency of the G-33A mutation (GA+AA genotypes) was significantly higher in the CAD group (23.8% vs 15.5%, odds ratio [OR] 1.70, p = 0.031). Multiple logistic regression analysis showed that the mutation was an independent risk factor (OR 1.81, p = 0.016) for CAD, as was hypertension (OR 1.44, p = 0.040), diabetes mellitus (OR 2.50, p <0.001), and smoking (OR 2.15, p <0.001). In CAD patients with GG genotype, the soluble thrombomodulin level increased with the extent of CAD (36 +/- 15 vs 47 +/- 18 vs 55 +/- 36 ng/ml in 1-, 2-, or 3-vessel CAD, p <0.001). However, in CAD patients with G-33A mutation, there was no difference between the levels of soluble thrombomodulin (39 +/- 17 vs 37 +/- 15 vs 42 +/- 18 ng/ml, p = NS) in 1-, 2-, or 3-vessel CAD. Our observations suggest that there is a significant association of the G-33A mutation in thrombomodulin gene with CAD, and this mutation may influence the soluble thrombomodulin levels in patients with CAD.

Activation of nuclear factor kappaB and induction of inducible nitric oxide synthase by Ureaplasma urealyticum in macrophages

Chronic lung disease (CLD) of prematurity is an inflammatory disease with a multifactorial etiology. The importance of Ureaplasma urealyticum in the development of CLD is debated, and steroids produce some improvement in neonates with this disease. In the present study, the capability of U. urealyticum to stimulate rat alveolar macrophages to produce nitric oxide (NO), express inducible nitric oxide synthase (iNOS), and activate nuclear factor kappaB (NF-kappaB) in vitro was characterized. The effect of NO on the growth of U. urealyticum was also investigated. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (> or =4 x 10(7) color-changing units/ml) stimulated alveolar macrophages to produce NO in a dose- and time-dependent manner (P<0.05). This effect was further enhanced by gamma interferon (100 IU/ml; P<0.05) but was attenuated by budesonide and dexamethasone (10(-4) to 10(-6) M) (P<0.05). The mRNA and protein levels of iNOS were also induced in response to U. urealyticum and inhibited by steroids. U. urealyticum antigen triggered NF-kappaB activation, a possible mechanism for the induced iNOS expression, which also was inhibited by steroids. NO induced by U. urealyticum caused a sixfold reduction of its own growth after infection for 10 h. Our findings imply that U. urealyticum may be an important factor in the development of CLD. The host defense response against U. urealyticum infection may also be influenced by NO. The down-regulatory effect of steroids on NF-kappaB activation, iNOS expression, and NO production might partly explain the beneficial effect of steroids in neonates with CLD.

Elevation of soluble adhesion molecules is associated with the severity of myocardial damage in acute myocardial infarction

In 20 patients with acute myocardial infarction, blood samples were taken to study the serial changes in the soluble intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin. Results indicated that soluble ICAM-1 increased significantly and persisted throughout the study period; however, soluble E-selectin was significantly elevated only transiently and decreased rapidly thereafter, and the VCAM-1 did not increase during entire study period. There was a significant correlation between the levels of ICAM-1, E-selectin 6 hours after admission, and peak creatine kinase level; the levels of ICAM-1 and E-selectin were also positively correlated with total leukocyte count at admission.

Stereotactic radiosurgery for primary trigeminal neuralgia using the Leksell Gamma unit

OBJECTIVE

Previous papers have reported Gamma Knife radiosurgery to be a safe, effective method for primary trigeminal neuralgia. Since November 1996, we have treated primary trigeminal neuralgia using the Leksell Gamma Knife at the Tianjin Medical University. The present study reports clinical results of Gamma Knife radiosurgery in the treatment of trigeminal neuralgia in 80 cases.

METHODS

The mean patient age was 67 years (range 32-92), the mean duration of facial pain was 7.6 years (range 1.5-29). The male:female ratio was 31:49. The right side of the face was involved in 45 patients (56.25%) and the left side in 30 cases (37.5%), with bilateral involvement in 5 cases (6.25%). Under local anesthesia, all patients underwent stereotactic MRI to identify the trigeminal nerve. A single isocenter, using a 4-mm collimator, was positioned at the sensory root of the trigeminal nerve entry zone of the pons, 4-6 mm from the brainstem surface, so that no more than the 20% isodose was administered to the brainstem. The maximum dose was between 70 and 90 Gy, with a mean of 75.6 Gy. For bilateral trigeminal neuralgia, two separate matrices were employed, and bilateral Gamma Knife radiosurgery was performed on the same day.

RESULTS

Follow-up ranged from 12 to 43 months (mean 23.7 months). Neurological evaluation indicated excellent response in 42 cases (52.5%), good response in 25 cases (31.25%), effective response in 8 cases (10%), so the total pain control rate was 93.75%. The latency from Gamma Knife surgery to pain relief ranged from 1 to 120 days (mean 22 days). Among the 75 patients 7 with pain control experienced pain recurrence 5-26 months after being completely free from pain. A second Gamma Knife radiosurgery was performed in 7 recurrent cases and 5 patients with treatment failure. A maximal dose ranging from 70 to 80 Gy was given (mean 74.2 Gy). After a mean follow-up of 18 months (8-33 months), 9 patients achieved excellent results, and 2 had good results. The latency interval to pain relief ranged from 1 to 120 days (mean 15 days). Nine patients developed new facial numbness, while no other complication appeared in the remainder of the patients.

CONCLUSIONS

Gamma Knife radiosurgery is a safe and effective method in the treatment of trigeminal neuralgia once diagnosis is established.

Flagellin-PAc fusion protein is a high-efficacy anti-caries mucosal vaccine

We previously demonstrated that an anti-caries DNA vaccine intranasally administered with recombinant flagellin protein as a mucosal adjuvant enhanced salivary IgA response and conferred better protection against caries. However, the relatively weak immunogenicity of DNA vaccines and the necessity for a large quantity of antigens remain significant challenges. Here, we fused the flagellin derived from E. coli (KF) and target antigen PAc containing the A-P fragment of PAc from S. mutans (rPAc) to produce a single recombinant protein (KF-rPAc). The abilities of KF-rPAc to induce rPAc-specific mucosal and systemic responses and protective efficiency against caries following intranasal immunization were compared with those of rPAc alone or a mixture of rPAc and KF (KF + rPAc) in rats. Results showed that KF-rPAc promoted significantly higher rPAc-specific antibodies in serum as well as in saliva than did an equivalent dose of rPAc alone or a mixture of KF + rPAc. Intranasal immunization of 8.5 µg KF-rPAc could achieve 64.2% reduction of dental caries in rats. In conclusion, our study demonstrated that flagellin and PAc fusion strategy is promising for anti-caries vaccine development, and KF-rPAc could be used as an anti-caries mucosal vaccine.

Clinical implications of left atrial appendage function: its influence on thrombus formation

This study evaluated the relation between left atrial appendage (LAA) function and LAA spontaneous echo contrast (SEC) or thrombus formation. Seventy-five patients (45 men and 30 women, aged 14-79 years) referred for transesophageal echocardiography (TEE) were examined for LAA area (maximal and minimal), LAA ejection fraction ([LAA maximal area--LAA minimal area]/LAA maximal area), LAA peak emptying velocity, and these patients were classified into three groups by different LAA blood flow patterns: Group 1--25 patients with well-defined biphasic configuration of LAA flow; Group 2--28 patients with multiphasic configuration of LAA flow; Group 3--22 patients with very low LAA blood flow and, sometimes, barely detected Doppler signal. All the 25 patients in Group 1 had a sinus rhythm during TEE study, while the other 50 patients in Groups 2 and 3 were in atrial fibrillation. The patients in Group 3 had the lowest LAA ejection fraction and the lowest peak emptying velocity of these three groups. LAA SEC was present in five of 28 patients in Group 2 and 14 of 22 patients in Group 3, but in none of 25 patients in Group 1 (P < 0.001). LAA thrombus was present in one of 25 patients in Group 1, two of 28 patients in Group 2, and seven of 22 patients in Group 3 (P < 0.05). In conclusion, this study found that patients with poor LAA function, which was represented by lower LAA ejection fraction and lower peak emptying velocity, had higher incidence of LAA SEC or thrombus formation.

Hazardous chemicals: psychological dimensions of the health sequelae of a community exposure in Texas

STUDY OBJECTIVE

A chemical spill from an oil refinery exposed the local community to more than 40,000 lb of highly toxic and corrosive hydrofluoric acid. A community based symptom prevalence study found an association between exposure and physical symptoms: the psychological impact of the disaster and its potential effect on the reporting of physical symptoms is examined here.

DESIGN

The study used a population based survey design consisting of two phases: phase I, the exposure phase, and, phase II, the symptom prevalence phase.

SUBJECTS

In phase I, information indicative of exposure was collected on 10,811 individuals in a door to door survey of a geographically defined area. In phase II, symptom prevalence information was gathered through in-person interviews with 2509 subjects selected from the phase I census in a sampling scheme that balanced across the exposure categories with regard to age, gender, and predisposition. The refusal rate in both phases was < 5%.

MEASUREMENT AND MAIN RESULTS

Stepwise logistic regression analyses were used to assess the relative predictive importance of psychological variables and hydrofluoric acid exposure in explaining the reported physical symptoms two years after the disaster. The findings show a linear relationship between the level of hydrofluoric acid exposure and the degree of psychological stress two years after the accident. High exposure had a long term (more than two years) impact on physical health for some self reported symptoms, even after controlling for the psychological impact. Some physical symptom reports, however, were better explained by psychological status than by exposure to hydrofluoric acid. The physical symptoms for which exposure was the major predictor were those for which the biological plausibility of a relationship with hydrofluoric acid exposure was direct.

CONCLUSIONS

Measures of psychological status should be included in symptom studies of health sequelae to man-made disasters so that the physical effects of exposure can be more accurately assessed.

Prognostic significance of elevated hemostatic markers in patients with acute myocardial infarction

OBJECTIVES

The purpose of this study was to determine whether the elevated levels of hemostatic markers in the early phase of myocardial infarction may serve as risk factors for subsequent cardiac mortality.

BACKGROUND

Increased plasma hemostatic markers were noted in acute myocardial infarction, indicating that the blood coagulation system is highly activated in those patients. However, there are few clinical data concerning the association between the elevated hemostatic markers and survival in patients with myocardial infarction.

METHODS

Blood samples were obtained from 64 patients (mean age 67 +/- 11 years; 49 male) with acute myocardial infarction within 12 h after the onset of symptoms and before the initiation of any antithrombotic treatment. We measured plasma concentrations of fibrinopeptide A (FPA), prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complex (TAT) using the enzyme-linked immunosorbent assay method, and examined the associations between the level of these markers and survival with Cox proportional hazards models.

RESULTS

The follow-up time was 27 +/- 17 months, and 19 patients died of cardiac causes during the follow-up. Univariate survival analysis identified Killip class IV (hazard ratio 4.86; 95% confidence interval [CI] 1.55-15.19), left ventricular ejection fraction (hazard ratio 0.94; 95% CI 0.90-0.99), FPA (hazard ratio 1.54; 95% CI 1.13-2.10), F1+2 (hazard ratio 2.03; 95% CI 1.17-3.53) and TAT (hazard ratio 1.88; 95% CI 1.27-2.79) as significant factors associated with cardiac mortality. In multivariate analyses, only FPA level (hazard ratio 1.84; 95% CI 1.03-3.30) and left ventricular ejection fraction (hazard ratio 0.93; 95% CI 0.88-0.98) were independent predictors of cardiac mortality.

CONCLUSIONS

Elevated FPA in the early phase of myocardial infarction identifies patients with increased risk for subsequent cardiac death. This association appears to be independent of residual left ventricular function after infarction.

No change of brain extracellular catecholamine levels after acute catechol-O-methyltransferase inhibition: a microdialysis study in anaesthetized rats

Catechol-O-methyltransferase inhibitors have been newly introduced as adjunct drugs to the levodopa/dopa decarboxylase inhibitor therapy in Parkinson's disease. When given alone, catechol-O-methyltransferase inhibitors seem to affect behaviour. We wanted to determine whether the concentrations of free amine would be increased by catechol-O-methyltransferase inhibition with tolcapone and underpin the positive behavioural effects. To this end, dopamine and noradrenaline levels were analyzed in the microdialysis perfusion fluid collected from several brain regions in chloral hydrate anaesthetized rats. We also analyzed the turnover rate of catecholamines in the brain after single doses of tolcapone and entacapone using the alpha-methyl-p-tyrosine method. On their own, tolcapone (at 10 or 30 mg/kg) did not elevate dopamine or noradrenaline levels in any brain region studied although the formation of catechol-O-methyltransferase-dependent metabolites was strongly reduced. Neither tolcapone nor entacapone (at 30 mg/kg) affected the turnover rate of catecholamines. It seems that catechol-O-methyltransferase inhibitors do not alter behaviour by elevating extracellular levels of free catecholamines levels but other explanations are needed.

Synergistic induction of IL-10 by hypertonic saline solution and lipopolysaccharides in murine peritoneal macrophages

BACKGROUND

Liver injury after ischemia/reperfusion is an important cause of morbidity in surgical patients. We have shown that the preconditioning of animals that were subjected to liver ischemia/reperfusion with hypertonic saline solution (HTS) prevented injury by inhibiting Kupffer cell tumor necrosis factor (TNF) production. We postulated that the induction of anti-inflammatory interleukin-10 (IL-10) by HTS might contribute to protection.

METHODS

Murine thioglycolate--elicited peritoneal exudative macrophages (PEMs) were used to model the effects of HTS on IL-10 release from Kupffer cells. Cells were preconditioned with 500 mOsm HTS (or isotonic saline medium) for 2 hours and then stimulated with lipopolysaccharide (LPS; 1 microg/mL) or vehicle for 4 hours under isotonic conditions. TNF-alpha and IL-10 were measured in the culture supernatant by enzyme-linked immunosorbent assay; TNF, IL-10, and SOCS-3 messenger RNA expression were assessed by Northern blot. NF-kappa B activation was examined by electrophoretic mobility shift assay and Western blot for I kappa B degradation.

RESULTS

In the absence of LPS, isotonic medium--and HTS-pretreated PEMs produced little IL-10 (24.9 +/- 66.0 and 0 pg/mL, respectively); however, stimulation of PEMs with LPS increased IL-10 (134.9 +/- 72.2 pg/mL). Preconditioning with HTS significantly augmented LPS-induced IL-10 production, resulting in a 2-fold increase in IL-10 compared with the isotonic solution LPS group (270.7 +/- 106.8 pg/mL; P <.01). HTS alone increased IL-10 mRNA levels and markedly augmented levels induced by LPS alone. To determine whether IL-10 accounted for HTS-induced TNF inhibition, cells from IL-10 knockout animals were studied. A lack of IL-10 did not reverse the inhibitory effect of HTS on LPS-induced TNF. NF-kappa B activation was the same in HTS-and isotonic solution--pretreated groups after LPS.

CONCLUSIONS

HTS augments IL-10 induction by LPS at the gene level. Although TNF is reduced, it is not causally related to increased IL-10 or altered NF-kappa B signaling. HTS might exert its beneficial effects by independently modulating pro- and anti-inflammatory molecules, accounting for the potent immunomodulation exerted by HTS in vivo.

Oily skin: specific features in Chinese women

BACKGROUND/PURPOSE

Inconsistent data are available on the various types of skin, their prevalence and characterization, particularly regarding Asian skins. This observation prompted to conduct a large study in China to assess the prevalence of oily skin and identify the specific factors related to that type of skin.

METHODS

The multicentre trial involved 1787 Chinese women in Shenyang, Harbin, Beijing, Chengdu and Suzhou, between 18 and 65 years of age. Data on history of acne, the presence of environmental factors and a detailed self-evaluation of the skin were collected using a standardized questionnaire. A clinical evaluation of facial skin oiliness was carried-out by a dermatologist at each centre. Sebum secretion was measured on the forehead using Sebumeter SM810. Statistical analysis (multiple correspondence analysis) of typology was conducted based on self-evaluation data.

RESULTS

According to self-evaluation data, oily skin prevalence in the overall Chinese population of the study was 25.6%. Self-evaluation results were quite consistent with sebum measurements and with clinical assessment by dermatologist. Parameters associated with oily skin were (i) shiny skin and a past history of acne, (ii) irregular menstruation, and (iii) highly reactive or sensitive skin. Moreover, a clear and significant link was noted between oily skin and the ingestion of spicy or sweet food. Lastly, sebum levels were found to be twice as high in Beijing as in the other cities and were correlated to higher oily skin prevalence.

CONCLUSION

The study demonstrated the capacity of women for proper self-evaluation of their skin type. It also suggests a potential link between nutritional factors such as spicy and/or sweet diets and oily skin as well as between sensitive and oily skin in this population.

Modulation of inflammation-induced changes in insulin-like growth factor (IGF)-I and IGF binding protein-1 by anti-TNF antibody

The aim of the present study was to characterize changes in the insulin-like growth factor (IGF) system produced by the nonbacterial nonendotoxic inflammatory agent zymosan and to determine whether these changes were mediated by enhanced production of tumor necrosis factor (TNF). Rats were injected intraperitoneally with either zymosan or saline and studied 18 h later. Animals were pretreated with either nonimmune IgG or neutralizing anti-TNF antibody 2 h before zymosan injection. Zymosan increased the plasma concentration of TNF alpha, and this was associated with a decrease (approximately 40%) in the IGF-I concentration in plasma, liver, heart, and brain. The IGF-I content was not altered in skeletal muscle and kidney. Zymosan also increased the concentration of IGF binding protein (BP)-1 in plasma (120%), liver (90%), and muscle (470%). Circulating TNF alpha was not detectable in rats injected with anti-TNF antibody before zymosan. The neutralizing antibody prevented the zymosan-induced reduction in IGF-I in plasma and blunted the decreased observed in liver, but did not alter the decrease in heart or brain. Anti-TNF antibody also attenuated (40-60%) the increased IGFBP-1 in plasma, liver, and muscle observed in zymosan-treated rats. We conclude that zymosan-induced inflammation not only decreases IGF-I in plasma and selected tissues, but also increases IGFBP-1 in plasma, liver, and muscle, and that these alterations are due in large part to the enhanced production of TNF alpha.