Nacre extract restores the mineralization capacity of subchondral osteoarthritis osteoblasts.

Osteoarthritis (OA) is the most common cause of joint chronic pain and involves the entire joints. Subchondral osteoarthritic osteoblasts present a mineralization defect and, to date, only a few molecules (Vitamin D3 and Bone Morphogenetic Protein2) could improve the mineralization potential of this cell type. In this context, we have tested for the first time the effect of nacre extract on the mineralization capacity of osteoblasts from OA patients. Nacre extract is known to contain osteogenic molecules which have demonstrated their activities notably on the MC3T3 pre-osteoblastic cell line. For this goal, molecules were extracted from nacre (ESM, Ethanol Soluble Matrix) and tested on osteoblasts of the subchondral bone from OA patients undergoing total knee replacement and on MC3T3 cells for comparison. We chose to investigate the mineralization with Alizarin Red staining and with the study of extracellular matrix (ECM) structure and composition. In a complementary way the structure of the ECM secreted during the mineralization phase was investigated using second harmonic generation (SHG). Nacre extract was able to induce the early presence (after 7 days) of precipitated calcium in cells. Raman spectroscopy and electron microscopy showed the presence of nanograins of an early crystalline form of calcium phosphate in OA osteoblasts ECM and hydroxyapatite in MC3T3 ECM. SHG collagen fibers signal was present in both cell types but lower for OA osteoblasts. In conclusion, nacre extract was able to rapidly restore the mineralization capacity of osteoarthritis osteoblasts, therefore confirming the potential of nacre as a source of osteogenic compounds.

Melissa officinalis extract induces apoptosis and inhibits proliferation in colon cancer cells through formation of reactive oxygen species.

PURPOSE: Efficient strategies for the prevention of colon cancer are extensively being explored, including dietary intervention and the development of novel phytopharmaceuticals. Safe extracts of edible plants contain structurally diverse molecules that can effectively interfere with multi-factorial diseases such as colon cancer. In this study, we describe the antiproliferative and proapoptotic effects of ethanolic lemon balm (Melissa officinalis) leaves extract in human colon carcinoma cells. We further investigated the role of extra- and intracellular reactive oxygen species (ROS). METHODS: Antitumor effects of lemon balm extract (LBE) were investigated in HT-29 and T84 human colon carcinoma cells. Inhibition of proliferation was analyzed by DNA quantification. The causal cell cycle arrest was determined by flow cytometry of propidium iodide-stained cells and by immunoblotting of cell cycle regulator proteins. To investigate apoptosis, cleavage of caspases 3 and 7 was detected by immunoblotting and fluorescence microscopy. Phosphatidylserine externalization was measured by Annexin V assays. Mechanistic insights were gained by measurement of ROS using the indicator dyes CM-H2DCFDA and Cell ROX Green. RESULTS: After 3 and 4 days of treatment, LBE inhibited the proliferation of HT-29 and T84 colon carcinoma cells with an inhibitory concentration (IC50) of 346 and 120 µg/ml, respectively. Antiproliferative effects were associated with a G2/M cell cycle arrest and reduced protein expression of cyclin dependent kinases (CDK) 2, 4, 6, cyclin D3, and induced expression of cyclin-dependent kinase inhibitor 2C (p18) and 1A (p21). LBE (600 µg/ml) induced cleavage of caspases 3 and 7 and phosphatidylserine externalization. LBE-induced apoptosis was further associated with formation of ROS, whereas quenching of ROS by antioxidants completely rescued the colon carcinoma cells from LBE-induced apoptosis. CONCLUSIONS: Lemon balm (Melissa officinalis) extract inhibits the proliferation of colon carcinoma cells and induces apoptosis through formation of ROS. Taken together, LBE or subfractions thereof could be used for the prevention of colon cancer.

Comparison between intact and bioactive parathyroid hormone assays in patients with severe heart failure.

OBJECTIVES: Parathyroid hormone (PTH) is a major systemic calcium-regulating hormone. Recent evidence has suggested that measurement of PTH might provide complementary information for the diagnosis and risk stratification of patients with heart failure (HF). The aim of our study was to compare intact and bioactive PTH assays in patients with severe heart failure. DESIGN AND METHODS: The following measurements were carried out in blood samples from 73 patients with severe heart failure: bioactive PTH (1-84) assay, intact PTH assay, non-PTH (1-84), 25-hydroxyvitamin D, B-type natriuretic peptide (BNP), N-terminal proBNP (Nt-proBNP), Galectin-3 and high sensitive troponin T (hsTnT). RESULTS: The correlation between intact and bioactive PTH assays was very high in HF patients. However, the bioactive PTH concentrations were lower than those measured with the intact assay. Intact and bioactive PTH as well as non-PTH (1-84) was significantly and positively correlated to BNP, Nt-proBNP, and galectin-3 but not to hsTnT. The strongest relationships with these cardiac biomarkers and with cardiovascular death were observed with the bioactive PTH assay. CONCLUSIONS: The PTH concentrations obtained with intact and bioactive assays are not comparable in patients with severe HF. The specificity of PTH assays might therefore impact on the potential diagnosis and prognosis values of PTH testing in patients with heart failure.

Serial analysis of gene expression in the southern cattle tick following acaricide treatment of larvae from organophosphate resistant and susceptible strains.

Organophosphate resistant and susceptible tick larvae from laboratory strains of the southern cattle tick, Rhipicephalus (Boophilus) microplus were exposed to low doses of the organophosphate (OP) acaricide, coumaphos. Serial analysis of gene expression (SAGE) was used to analyse differential gene expression in response to OP treatment and to compare the responses of OP-treated and -untreated resistant and susceptible tick larvae. An R. microplus Gene Index was used as an EST database to identify genes which corresponded to SAGE tags whose abundance changed in response to acaricide exposure. Relative quantitative RT-PCR was used to confirm the differential expression results from the SAGE experiments. Of particular interest is a SAGE tag which corresponds to a cytochrome P450-like EST in the Gene Index which was more abundant in untreated OP resistant larvae compared to untreated OP susceptible larvae. This SAGE tag was also more abundant in OP resistant larvae treated with OP compared to OP susceptible larvae treated with OP.

Identification of calconectin, a calcium-binding protein specifically expressed by the mantle of Pinctada margaritifera.

Nacre or mother-of-pearl in the shell of Pinctada margaritifera is composed of 95-99% calcium carbonate and 1-5% organic matrix. In this study, we developed an original technique to characterize the genes differentially expressed in nacre-forming cells (NFC) by combining suppression subtractive hybridization (SSH), to establish a cDNA subtractive library, with rapid amplification of cDNA ends (RACE)-PCR. Seventy-two specific cDNA sequences have been obtained so far. These include a protein containing two EF-hand Ca2+-binding domains which was completely sequenced after amplification by RACE-PCR. Its specific expression as well as the specificity of the SSH method was confirmed by semi-quantitative RT-PCR on NFC and mantle cells.

[Long-term results of alumina-on-alumina total hip arthroplasty]. / Résultats à long terme du couple de frottement alumine/alumine sur 98 prothèses de hanche cimentées.

PURPOSE OF THE STUDY: Mechanical failure in total hip arthroplasty is usually related to aseptic loosening itself related to wear particles as seen with polyethylene bearings. Alumina has bee proposed to avoid wear problems. In vitro and mid-term clinical studies have shown tribological advantages but early acetabular fixation remains an issue. Since alumina-on-alumina bearings are currently used with new fixation techniques, updated evaluations of older series are informative regarding the long-term tolerance of alumina in vivo. MATERIAL AND METHODS: We investigated 104 consecutive alumin-on-alumina cemented total hip arthroplasties (Cervaer-Osteal, Roissy, France) implanted 20 years ago in 81 patients (from 1979 to 1983). A32-mm alumina femoral head was used. The alumina acetabular socket and the titanium femoral stem were cemented. The Postel-Merle-d'Aubigne score was used for clinical evaluation. Radiological wear and development of osteolysis or loosening were noted for establishing actuarial curves. When accessible, histological samples from revision procedures were analyze. RESULTS: Six infected cases were not taken into account for data analysis. The average follow-up was 11 years, reaching 18 years in 38 cases. Twenty-three hips were revised for changing 23 acetabular sockets, 12 femoral heads, and one femoral stem. We noted one femoral head fracture, 24 definite acetabular loosenings, 12 probable acetabular loosenings, and 3 definite femoral loosenings. Radiological acetabular osteolysis was present in 4 cases, always limited to De Lee zone 1, and associated with loosening. Radiological wear was below eye detection. Periprosthetic tissue showed non-specific histological reactions to cement particles. Survival rate at 20 years was 62.8% [49.3-76.2%], in terms of revision 57.1% [42.5-71.7%] and 95.2% [89.9-100%] in terms of definite acetabular and femoral loosening. DISCUSSION: Besides the high rate of cemented fixation failure of the socket, loosened and non-loosened cases showed an excellent long-term tolerance of the alumina-on-alumina bearing with normal wear and osteolysis. This may also have protected the femoral component from complications. This study confirms in vivo the long-term tribological benefit of the alumina-on-alumina bearing in total hip arthroplasty and suggests that acetabular fixation should be improved to achieve full benefit.

Influence of highly active antiretroviral therapy on micronutrient profiles in HIV-infected patients.

OBJECTIVES: To assess micronutrient variations in HIV/AIDS patients before and after HAART (highly active antiretroviral therapy). METHODS: We evaluated the nutritional status and micronutrients in 44 patients over 3 years. The first nutritional evaluation was conducted in 1995 before HAART, the second was conducted in 1998 when most patients received HAART. RESULTS: Thirty-four (77%) of the patients were intravenous drug users. In 1995, 35 (80%) were receiving antiretroviral therapy, but none had a protease inhibitor. A comparison made between patients in the group with CD4 <250/mm(3) (group A) and patients in the group with CD4 >250/mm(3)(group B) revealed significantly lower levels of plasma selenium concentrations (p < 0.05). In group A women, zinc was significantly lower than in men of the same group (p < 0.05). On the contrary, selenium plasma concentrations were significantly lower in group A men than in group A women (p < 0.05). No significant differences were noted for other micronutrients. In 1998, when most patients were treated with HAART, differences between the two groups were no more significant, neither for selenium nor for zinc matched with sex. Micronutrient values did not significantly differ between patients with viral load below 5,000 copies/ml and patients with viral load above 5,000 copies/ml. Patients treated with HAART had practically no weight loss. Although patients who did not receive HAART had a good immune status, the mean weight loss was up to 4.6 kg. CONCLUSIONS: Selenium and zinc deficiencies are dependent on immune status and sex in HIV/AIDS patients. Other micronutrients do not seem to be influenced by the immune status in these patients. HAART reduces selenium and zinc deficiencies and may help avoid weight loss independently of the CD4 cell count.

Therapeutic use of selected herbs.

An increasing number of people in the United States are using herbs for health promotion and specific symptom management. Herbs are used to initiate healing through synergistic responses unlike the specific properties of pharmaceuticals. Anecdotal data comprise much of the popular information available about herbs. Scientific studies of the efficacy and safety of herbs, although on the rise, are less available than other drug trials. Clinicians need an appropriate knowledge base for dealing with patients who take herbal preparations as well as the ability to confidently include herbal preparations in their formulary. In this article, five common herbs are reviewed. The effects, clinical studies, side effects, and dosing regimens for aloe vera, arnica, black cohosh, evening primrose oil, and saw palmetto are described.

Dose-related hemodynamic and electrocardiographic effects of the calcium promoter BAY y 5959 in the presence or absence of congestive heart failure.

OBJECTIVES: The aim of this study was to assess the cardiovascular effects of BAY y 5959, a calcium promoter modulating myocardial calcium channels, in the presence or absence of congestive heart failure. BACKGROUND: There is still a clinical need for short-term administration of intravenous positive inotropes. BAY y 5959 was developed as a new approach to increase myocardial performance by selectively enhancing calcium influx in the myocytes. METHODS: Forty-one patients (21 without and 20 with congestive heart failure) were studied in an open label, dose-ranging study. Hemodynamic variables (including left ventricular [LV] angiography) and plasma samples were obtained at baseline and after 20 min of intravenous infusion of BAY y 5959 at doses ranging from 0.25 to 4.5 microg/kg body weight per min. RESULTS: In both study groups, BAY y 5959 produced dose-dependent increases in the indexes of inotropic state, without affecting isovolumetric relaxation rate. The magnitude of the response was comparable in patients with or without heart failure (average 38% increase in maximal first derivative of LV pressure [dP/dt max] at plasma levels of 100 microg/liter). BAY y 5959 also induced mild but statistically significant bradycardia and significantly decreased end-systolic volume while producing a leftward shift of the pressure-volume loop. Mean aortic pressure was unaffected at doses up to 3.0 microg/kg per min, and cardiac index improved in patients with heart failure at doses of 2.0 microg/kg per min (+23%, p < 0.05). However, at a dose of 4.5 microg/kg per min, mean aortic pressure and LV systolic wall stress increased, suggesting systemic vasoconstriction. The QT interval was also prolonged significantly at most doses. CONCLUSIONS: BAY y 5959 exhibits positive inotropic effects in patients with and without heart failure. The optimal response--combining bradycardia, reduced preload and improved cardiac output--appeared to be achieved at a dose of approximately 2.0 microg/kg per min. The impact of QT prolongation with regard to potential antiarrhythmic or proarrhythmic effects is unclear at this time.

Dietary prevention of osteoporosis.

Osteoporosis is a major health problem facing women and men, and the number of people affected is likely to increase substantially as the population ages. The gold standard for treatment has always been prevention. This article reviews therapeutic options, with an emphasis on nutrition; outlines current recommendations for calcium and vitamin D throughout the life span; and discusses food and supplemental sources of calcium. Guidelines are given for identifying high- and low-risk patients, and appropriate interventions are highlighted.

Treatment of Pseudomonas aeruginosa-infected orthopedic prostheses with ceftazidime-ciprofloxacin antibiotic combination.

Indwelling device infections are associated with considerable morbidity and extremely high cost. Pseudomonas aeruginosa is the most frequent gram-negative etiologic agent associated with infections of indwelling catheters and foreign body implants. It is generally agreed that eradication of infection in the presence of a foreign body requires removal of the foreign body. Using a combination of ceftazidime and ciprofloxacin, we cured nine of nine patients with P. aeruginosa-infected osteosynthetic material and four of five patients with hip and knee prostheses without removing the foreign material. Follow-up was for a mean of 21 months (range, 6 to 60 months). Some patients experienced minor side effects (arthralgia in one patient and rash in another patient). We conclude that this combination is effective and safe and should be useful in the treatment of P. aeruginosa-infected orthopedic implants.

Theophylline pharmacokinetics and metabolism in rabbits following single and repeated administration of Capsicum fruit.

Pharmacokinetics and metabolism of theophylline were studied in three groups of male rabbits, after intravenous administration (12 mg/kg), with and without oral ground Capsicum fruit suspension. Compared with control values, plasma theophylline half-life of distribution and of elimination, areas under plasma curves, clearance and volume of distribution did not show any significant difference. On the contrary, the elimination rate constant (k1,0) is significantly different (0.01 < P < 0.05) after a single dose of capsicum and remained unchanged after a repeated dose. Concerning the metabolism of theophylline in rabbits, the results showed that the oral administration of a single dose of Capsicum fruit suspension does not significantly affect the urinary excretion of theophylline and its metabolites--1,3-dimethyluric acid (1,3-DMU) and 1-methyluric acid (1-MU). On the other hand, after a repeated dose of Capsicum fruit for 7 days, the quantity of 1-MU was significantly reduced (0.01 < P < 0.05). In conclusion, it was found that a single dose of Capsicum fruit could affect pharmacokinetic parameters of theophylline (k1,0), while a repeated dose affected the metabolic pathway of xanthine oxidase.

Effects of nisoldipine therapy on myocardial perfusion and neuro-hormonal status in patients with severe ischaemic left ventricular dysfunction.

The effects of nisoldipine on regional myocardial perfusion and neuro-hormonal status were assessed in a double-blind, placebo-controlled study of 32 patients. All patients had ischaemic left ventricular dysfunction, with a left ventricular ejection fraction between 25% and 35%; per protocol, they were stratified according to concomitant use of ACE inhibitors. After baseline measurements at rest, including single photon emission computed tomography (SPECT) with Tc-MIBI, plasma neuro-hormones (norepinephrine, renin, arginine vasopressin, atrial natriuretic peptide) and echocardiography, the patients were randomized to nisoldipine (core coat tablet, 20 mg once daily; n = 16) or placebo (n = 16). Measurements were repeated after 8 weeks. SPECT data were analysed qualitatively (visual comparison by blinded observer) and quantitatively to derive an index of hypoperfusion representing the percentage of the left ventricular mass with Tc-MIBI activity below normal. At baseline, all patients had left ventricular areas with reduced Tc-MIBI uptake and 29 patients also had increases in plasma neuro-hormones. With nisoldipine, the extent of hypoperfusion (quantitative analysis) was reduced in 8/14 patients vs only 2/14 patients with placebo (P = 0.046, 2-tailed test). The benefit of nisoldipine was similar in patients with or without ACE inhibitor therapy and was also confirmed by the visual analysis of the data. Further, none of the neuro-hormones examined was significantly modified by nisoldipine. Thus, chronically underperfused areas are present at rest in patients with ischaemic left ventricular dysfunction, and nisoldipine significantly improved Tc-MIBI uptake in these areas without evidence of detrimental changes in plasma neuro-hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Nisoldipine in severe ischaemic left ventricular dysfunction.

The use of calcium antagonists in patients with severe dysfunction is controversial because agents like verapamil, diltiazem and nifedipine have been shown to worsen or precipitate congestive heart failure. However, successive improvements in our understanding of the clinical pharmacology of these drugs, of their pharmacokinetics and of their action on several neuro-humoral regulatory mechanisms have led to a continuous improvement of the molecules available. Promising results have been obtained with nisoldipine in patients with ischaemic left ventricular dysfunction (improved exercise tolerance, improved diastolic filling probably related to a relative improvement of chronically ischaemic areas) and other studies are exploring the effects of the combination of nisoldipine with an ACE-inhibitor. Soon, these trials should tell us if there is a real clinical benefit in the use of this agent not only to improve symptoms but also to slow down progression of the ventricular dysfunction.

[Treatment of eruptive rickettsioses. Review of the literature from the microbiology to the clinic]. / Traitement des rickettsioses éruptives. Revue de la littérature de la microbiologie à la clinique.

The authors review the literature concerning the treatment of rickettsiosis including Rocky Mountain spotted fever, Mediterranean spotted fever, murine typhus, and Scrub typhus. They report in vitro antibiotic susceptibilities of the causing organisms and in vivo activity on animal models. They also report their clinical experience and these of the literature in the treatment of rickettsiosis.

Analysis of the mechanisms underlying the changes in left ventricular filling dynamics during oral nisoldipine therapy in patients with anterior myocardial infarction.

The aim of this study was to clarify the mechanisms responsible for the increase in early filling rate observed during oral nisoldipine therapy in patients with ischaemic left ventricular (LV) dysfunction. For that purpose, the global and regional LV function was analysed before and after 2 months of double-blind monotherapy with nisoldipine (10 mg twice daily) or a placebo, in 17 patients with a previous anterior myocardial infarction. The baseline LV ejection fraction ranged from 34-51% and no patient had heart failure. Compared to the placebo, nisoldipine significantly lowered LV systolic pressure and end-diastolic pressure (-3 mmHg vs +6 with the placebo; P less than 0.01) and the LV pressure at the time of mitral opening (-2.0 +/- 3.4 mmHg vs +3.5 +/- 3.0; P less than 0.01). Despite this reduction in driving pressure, the global LV early peak filling rate improved with nisoldipine only and this improvement was related to a selective increase in expansion rate of the anterior areas, from 1010 +/- 360 to 1339 +/- 496 mm2.s-1 (P less than 0.001). The time to regional peak filling rate (-8%; P less than 0.01), the asynchrony of diastolic wall motion and the regional ejection fraction (33 +/- 10 to 38 +/- 12%; P less than 0.001) also improved in the anterior areas with nisoldipine but not with the placebo. In contrast, in the inferior, control zones, the regional ejection fraction and filling rate remained unchanged, both when compared to baseline and to the placebo.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of prolonged nisoldipine administration on the "hibernating" myocardium.

To assess the effects of nisoldipine on chronically underperfused myocardial areas ("hibernating myocardium"), the global and regional left ventricular (LV) function was analyzed before and after 2 months of double-blind monotherapy with nisoldipine (10 mg twice daily) or placebo in 17 patients with a previous anterior myocardial infarction. The baseline LV ejection fraction ranged from 34 to 51%, and no patient had heart failure. Compared to placebo, nisoldipine significantly lowered the LV systolic pressure and end-diastolic pressure (-3 vs. +6 mmHg with placebo; p < 0.01) and the LV pressure at the time of mitral valve opening (-2.0 +/- 3.4 vs. +3.5 +/- 3.0 mm Hg; p < 0.01). Despite this reduction in driving pressure, the global LV early peak filling rate improved only with nisoldipine and this improvement was related to a selective increase in the expansion rate of the anterior areas, from 1,010 +/- 360 to 1,339 +/- 496 mm2/s (p < 0.001). The time to regional peak filling rate (-8%; p < 0.01), the asynchrony of diastolic wall motion, and the regional ejection fraction (33 +/- 10 to 38 +/- 12%; p < 0.001) also improved in the anterior areas with nisoldipine but not with placebo. In contrast, in the inferior control zones, the regional ejection fraction and filling rate remained unchanged, both when compared to baseline and to placebo. In conclusion, prolonged nisoldipine therapy had no significant effect on the normal myocardium but improved systolic and diastolic function in hypokinetic areas.(ABSTRACT TRUNCATED AT 250 WORDS)

Ureaplasma in semen and IVF.

Ureaplasma urealyticum (U.U.) screening has been systematically performed in tests carried out before IVF cycles. In 42% of the cases (306 couples), at least one partner presented a monomicrobian U.U. infection. U.U. infection of at least one fraction of the split ejaculate was observed in 32% of the cases and found in similar proportions at the prostatic and seminal vesicle levels. The U.U.-infected group presented a similar number of cytological abnormalities to the noninfected samples. However, there was a significant reduction in the pregnancy rate after embryo transfer in the infected group whereas U.U. did not alter fertilization parameters, embryo retrieval or pregnancy rates per puncture. The preliminary results of a complementary prospective study (70 couples) point to the likely role of sexually transmitted Ureaplasma at the endometrial level.

Changes in myocardial metabolism during therapy in patients with chronic stable angina: a comparison of long-term dosing with propranolol and nicardipine.

The long-term effects of antianginal therapy on coronary blood flow and myocardial metabolism were studied in 35 patients with chronic stable angina. Arterial and coronary sinus blood samples and coronary blood flow measurements were obtained before and after 1 month of oral administration of propranolol or of the calcium antagonist nicardipine. When the data obtained at a fixed heart rate (10% to 15% above the pretreatment sinus rhythm) were compared, no significant differences were evidenced between the propranolol and the nicardipine groups. Coronary blood flow and myocardial oxygen uptake were unchanged with both drugs. Myocardial lactate uptake increased in 11 patients of the propranolol group (from -2 +/- 42 to 66 +/- 47 mumol/min, p less than .001) and in 11 patients of the nicardipine group (from 0 +/- 36 to 31 +/- 29 mumol/min, p less than .001). In these 22 patients, the increase in lactate uptake was accompanied by reductions in uptake of free fatty acids and by a decrease in the coronary sinus concentration of thromboxane B2 from 131 +/- 87 to 61 +/- 32 pg/ml (p less than .01), whereas the transcardiac release of prostacyclin increased. None of these changes in free fatty acids or in prostanoid handling were observed in the nine patients (five in the propranolol and four in the nicardipine group) in whom lactate uptake was not augmented. During pacing-induced tachycardia, the metabolic effects of the two drugs appeared different. Myocardial lactate uptake decreased more in the patients receiving propranolol than in those receiving nicardipine and the combined productions of alanine and glutamine rose by 3.2 +/- 5.8 mumol/min in the propranolol group while it decreased by 3.1 +/- 8.2 mumol/min in the nicardipine group (p less than .025 propranolol vs nicardipine). In conclusion, long-term antianginal therapy with propranolol or nicardipine improved several markers of myocardial ischemia in approximately two-thirds of the patients. Although the changes observed at low heart rates were similar with the two drugs, the data also suggest that better metabolic protection is provided by the calcium antagonist during pacing-induced tachycardia.