The effect of low dose diclofenac sodium administered locally on heterotopic bone formation in rats

Summary The effect of a low dose of diclofenac sodium, administered locally, on heterotopic bone formation in rats was investigated. Heterotopic bone was induced by implantation of demineralised bone matrix into the gluteal muscles. Diclofenac was released continuously for 2 weeks from micro-osmotic pumps for each demineralised bone implant in the rats. Each had a control implant in the opposite gluteal muscle to which saline was released in the same way. The yield of new woven bone was determined after 4 weeks by measuring the ash-weights of the implants. Those of the diclofenac samples were significantly decreased compared to the controls. These results suggest that a low dose of diclofenac given locally decreases heterotopic bone formation in rats.

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Résumé L'effet, sur la formation d'os hétérotopic d'une petite dose de diclofenac sodium administrée localement a été étudié chez le rat. Les ossifications hétéropiques ont été crées par l'implantation d'une matrice osseuse déminéralisée dans le muscle fessier des rats. Le diclofenac (0,2 microgramme par ml) a été délivré de façon continue pendant 2 semaines par des pompes micro-osmotiques (200 l) au niveau du fragment d'os déminéralisé. Chaque animal a eu un fragment d'os déminéralisé de contrôle placé dans le muscle fessier contro-latéral et au niveau duquel une solution saline (0,9% NaCl) a été administrée de la même façon. La formation d'os nouveau a été déterminée après 4 semaines par la mesure du poids des fragments osseux réduits en cendres. Le poids des cendres des échantillons traités au diclofenac est significativement plus faible que celui des contrôles (p inférieur à 0,05). Nos résultats indiquent qu'une faible dose de diclofenac administrée localement, décroit expérimentalement la formation d'os hétérotopic chez le rat.

     

Electrophysiological indices of acute effects of ethanol on involuntary attention shifting

Dose-related effects of ethanol (placebo, 0.30, and 0.60 g/kg) on behavioral and event-related brain potential (ERP) indices of involuntary attention shifting of audition were investigated. ERPs were recorded from 11 healthy social drinkers during a forced-choice reaction-time (RT) task. Subjects were presented with 100 and 200 ms tones (P = 0.50 for each) with a constant inter-stimulus interval (ISI) of 1 s. The task was to press either of two buttons, depending on the tone duration. The majority of the tones (“standards”) were of 700 Hz (P = 0.82). Occasionally, however, the frequency of the tones changed, deviating either slightly (750 Hz), moderately (900 Hz), or widely (1200 Hz; P = 0.06 for each) from the standard frequency. In accordance with previous findings, the task-irrelevant frequency deviations prolonged the RT. This RT prolongation was attenuated by alcohol with the 0.3 g/kg dose, thus suggesting less distraction by irrelevant stimulus deviations under the influence of ethanol. Furthermore, the P3a, reflecting involuntary attention shifting, was suppressed by alcohol even with the 0.3 g/kg dose. These findings demonstrate a detrimental effect of alcohol on involuntary attention shifting, evident with doses considerably smaller than previously described, and still juridically acceptable in road traffic in most countries. Received: 19 December 1997/Final version: 26 May 1998     

Alcohol reduces prefrontal cortical excitability in humans: a combined TMS and EEG study.

The effects of alcohol (0.8 g/kg) on the prefrontal cortex were studied in nine healthy subjects using the technique of transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG). A total of 120 magnetic pulses were delivered with a figure-of-eight coil to the left prefrontal cortex at the rate of 0.4-0.7 Hz. The EEG was recorded simultaneously with 60 scalp electrodes (41 electrodes were used for analysis); the TMS-evoked activation was estimated by the area under the global mean field amplitude (GMFA) time curve. TMS caused changes in EEG activity lasting up to 270 ms poststimulus. Alcohol decreased GMFA at 30-270 ms poststimulus (713+/-303 vs 478+/-142 microV ms; p=0.007). Alcohol-induced differences were most pronounced at anterior electrodes. These results suggest that alcohol reduces the excitability in the prefrontal cortex.     

Antibodies against copper-oxidised and malondialdehyde-modified low density lipoproteins in pre-eclamptic pregnancies

Objective To measure auto-antibodies against oxidatively modified low density lipoprotein (LDL) in pre-eclamptic pregnancies using two different techniques.
Design Clinical study comparing pre-eclamptic and normal pregnancies.
Setting Tampere University Hospital, Finland.
Population Twenty-one primigravidae with pre-eclampsia and 13 healthy, normotensive primigravidae as controls.
Methods The serum titers of antibodies against both malondialdehyde-modified and copper-oxidised LDL (MDA-LDL and copper-ox LDL) were analysed and related to parameters reflecting the severity of pre-eclampsia.
Results There was a positive correlation (   r = 0.58  ) between antibodies against MDA-LDL and copper-ox LDL in women with pre-eclampsia but not in healthy pregnant controls. The antibody levels against copper-ox LDL, but not against MDA-LDL, were higher in women with pre-eclampsia than in women with a normal pregnancy (   P < 0.01  ). While the antibody titers against copper-ox LDL did not correlate with any parameter reflecting the severity of pre-eclampsia, those against MDA-LDL showed a positive correlation with the level of diastolic blood pressure (   r = 0.54  ) and a negative correlation with platelet count (   r = 461  ) in women with pre-eclampsia.
Conclusions There are increased titers of serum autoantibodies against copper-oxidised LDL in pre-eclampsia, which may reflect enhanced lipid peroxidation involving circulating lipoproteins.     

Delivery and stability of LHRH and Nafarelin in human skin: the effect of constant/pulsed iontophoresis.

Poor absorption and stability of peptides are the major obstacles concerning the development of therapeutically relevant iontophoretic devices for the transdermal delivery of peptides. The present study examined the impact of constant and pulsed (direct/alternating) current profiles on the transport and stability of two decapeptides LHRH and Nafarelin. The stability of these peptides was studied in a physiological buffer solution, with electrical current, and when the peptide solution was exposed to the stratum corneum or to the epidermal/dermal side of human skin. Pulsed direct current profile was shown to be the most efficient in transporting both LHRH and Nafarelin across the human epidermis. Furthermore, the percentage of intact LHRH in the receiver phase was slightly higher when a pulsed current profile was used. Both the peptides were stable in a physiological buffer and under the influence of current, but LHRH was degraded especially in contact with the dermal side of the skin. Altogether five hydrolytic degradation products of LHRH were observed, and they were identified by LC-ESI/MS and LC-ESI/MS/MS. No degradation products of Nafarelin were observed. It is concluded that the pulsed direct current profile may provide at least a partial solution for the transdermal delivery of peptides in terms of improved transport efficacy and peptide stability.     

Associations of urban air particulate composition with inflammatory and cytotoxic responses in RAW 246.7 cell line

Epidemiological studies show heterogeneities in the particulate pollution-related exposure–effect relationships among cardiorespiratory patients, but the connection to chemical composition and toxic properties of the inhaled particles is largely unknown. To identify the chemical constituents and sources responsible for the diverse inflammatory and cytotoxic effects of urban air, fine (PM_2.5–0.2) and coarse (PM_10–2.5) particulate samples were collected during contrasting air pollution situations. We exposed mouse RAW 246.7 macrophages for 24?hrs to PM_2.5–0.2 and PM_10–2.5 samples from six European cities. The concentrations of proinflammatory cytokines (IL-6, TNFα), chemokine (MIP-2), and nitric oxide were measured from the cell culture medium, and the cytotoxicity was assayed. Spearman’s correlations between the chemical constituents and cellular responses were analyzed. In the PM_2.5–0.2 size range, the tracers of photo-oxidation of organics in the atmosphere (oxalate, succinate, malonate), some transition metals (Ni, V, Fe, Cu, Cr), and insoluble soil constituents (Ca, Al, Fe, Si) correlated positively with the response parameters. In contrast, the tracers of incomplete biomass (monosaccharide anhydrides) and coal (As) combustion, and polycyclic aromatic hydrocarbons (PAHs), had negative correlations with the inflammatory activity. The compositions of PM_10–2.5 samples were more uniform and there were only occasional high correlations between the chemical constituents, endotoxin, and the response parameters. The present results suggest that the local sources of incomplete combustion and resuspended road dust are important producers of harmful fine particulate constituents that may, however, operate via diverse toxicity mechanisms. The results agree well with our recent findings in the mouse lung.     

The expression of cyclooxygenase-1 and -2 in proliferative endometrium and endometrial adenocarcinoma

BACKGROUND. The activity of cyclooxygenase-2 (COX-2) is increased in inflammation and in several cancer types. We investigated the expression of COX-2, cyclooxygenase-1 (COX-1), nitric oxide synthase-2 (NOS-2) and nitric oxide synthase-3 (NOS-3) in normal proliferative and secretory human endometrium, and in endometrial adenocarcinoma. METHODS. Human endometrium was collected at hysterectomy. Seven samples were in proliferative and 11 samples in secretory stage. Twelve specimens from endometrial carcinoma were collected, as well. Immunohistochemistry was used to investigate the expression of COX-1, COX-2, NOS-2 and NOS-3. RESULTS. COX-2 immunostaining was detected in most specimens of normal proliferative glandular epithelium (86%) and of endometrial carcinomas (92%). COX-2 staining was often detected in cancer cells on the border areas of the tumour and on the areas of invasive growth. Staining for COX-2 was seen in proliferative glands usually only in the basal layer of the endometrium. NOS-2 was usually absent or negligible in proliferative endometrial glands and also in the cancer cells of endometrial adenocarcinomas. No staining for either COX-2 or NOS-2 was seen in specimens of secretory glandular epithelium. The expression of the constitutive COX-1 and NOS-3 was negligible or weak in the glandular epithelium of proliferative and secretory endometrium and in endometrial cancer cells. CONCLUSIONS. The expression of the inducible COX-2 but not of COX-1 is stimulated in the glandular epithelium of proliferative endometrium and in the cancer cells of human endometrial adenocarcinoma, in particular in those in the borders of carcinoma and spreading into lymphatic vessels.     

Monitoring of gliomas in vivo by diffusion MRI and 1H MRS during gene therapy‐induced apoptosis: interrelationships between water diffusion and mobile lipids

The measurement of water diffusion by diffusion‐weighted MRI (DWI) in vivo offers a non‐invasive method for assessing tissue responses to anti‐cancer therapies. The pathway of cell death after anti‐cancer treatment is often apoptosis, which leads to accumulation of mobile lipids detectable by ¹H MRS in vivo. However, it is not known how these discrete MR markers of cell death relate to each other. In a rodent tumour model [i.e. ganciclovir‐treated herpes simplex thymidine kinase (HSV‐tk) gene‐transfected BT4C gliomas], we studied the interrelationships between water diffusion (Trace{D}) and mobile lipids during apoptosis. Water diffusion and water‐referenced concentrations of mobile lipids showed clearly increasing and interconnected trends during treatment. Of the accumulating ¹H MRS‐visible lipids, the fatty acid ? CH ?CH ? groups and cholesterol compounds showed the strongest associations with water diffusion (r² = 0.30; P < 0.05 and r² = 0.48; P < 0.01, respectively). These results indicate that the tumour histopathology and apoptotic processes during tumour shrinkage can be interrelated in vivo by DWI of tissue water and ¹H MRS of mobile lipids, respectively. However, there is considerable individual variation in the associations, particularly at the end of the treatment period, and in the relative compositions of the accumulating NMR‐visible lipids. The findings suggest that the assessment of individual treatment response in vivo may benefit from combining DWI and ¹H MRS. Absolute and relative changes in mobile lipids may indicate initiation of tumour shrinkage even when changes in tissue water diffusion are still small. Conversely, greatly increased water diffusion probably indicates that substantial cell decomposition has taken place in the tumour tissue when the ¹H MRS resonances of mobile lipids alone can no longer give a reliable estimate of tissue conditions. Copyright © 2008 John Wiley & Sons, Ltd.     

Diagnostic tools in respiratory tract infections: use and comparison with Finnish guidelines

The objectives of this prospective epidemiological study were to describe the diagnosis and treatment of respiratory tract infections by Finnish general practitioners and to compare current practice with national evidence-based guidelines. All patients (n = 4386) seeking primary care for a respiratory tract infection for the first time in 30 health centres during 1 week in November 1998 participated in the study. The main outcome measures were the amounts and types of diagnostic tests used and antimicrobials prescribed. Tympanometry was used in 1% of patients with acute otitis media. Ultrasonography, sinus radiography or both were used in 80% of cases of sinusitis and antigen detection or culture for Streptococci in 57% of throat infections. In acute bronchitis, a chest radiograph was taken in 5% of cases and the CRP level determined in 8%. The corresponding figures for pneumonia were 49% and 39%. In pneumonia and throat infection, diagnostic testing was statistically significantly associated with the use of antimicrobials, but not in otitis, sinusitis or acute bronchitis. Diagnostic tests were underused in respiratory tract infections compared to evidence-based recommendations.     

Quantitative ADME Proteomics – CYP and UGT Enzymes in the Beagle Dog Liver and Intestine

Pharmaceutical Research - Beagle dogs are used to study oral pharmacokinetics and guide development of drug formulations for human use. Since mechanistic insight into species differences is needed...