Effect of Sucralfate on the Relative Bioavailability of Enrofloxacin and Ciprofloxacin in Healthy Fed Dogs

Background

Sucralfate impairs absorption of ciprofloxacin and other fluoroquinolones in humans, but no sucralfate–fluoroquinolone interaction has been reported in dogs. Veterinary formularies recommend avoiding concurrent administration of these medications, which might impact compliance, therapeutic success, and resistance selection from fluoroquinolones.

Objectives

To determine whether a drug interaction exists when sucralfate is administered to fed dogs concurrently with ciprofloxacin or enrofloxacin, and whether a 2 hour delay between fluoroquinolone and sucralfate affects fluoroquinolone absorption.

Animals

Five healthy Greyhounds housed in a research colony.

Methods

This was a randomized crossover study. Treatments included oral ciprofloxacin (C) or oral enrofloxacin (E) alone, each fluoroquinolone concurrently with an oral suspension of sucralfate (CS, ES), and sucralfate suspension 2 hours after each fluoroquinolone (C2S, E2S). Fluoroquinolone concentrations were evaluated using liquid chromatography with mass spectrometry.

Results

Drug exposure of ciprofloxacin was highly variable (AUC 5.52–22.47 h μg/mL) compared to enrofloxacin (AUC 3.86–7.50 h μg/mL). The mean relative bioavailability for ciprofloxacin and concurrent sucralfate was 48% (range 8–143%) compared to ciprofloxacin alone. Relative bioavailability of ciprofloxacin improved to 87% (range 37–333%) when sucralfate was delayed by 2 hours. By contrast, relative bioavailability for enrofloxacin and concurrent sucralfate was 104% (94–115%).

Conclusions and Clinical Importance

A possible clinically relevant drug interaction for the relative bioavailability of ciprofloxacin with sucralfate was found. No significant difference in bioavailability was documented for enrofloxacin with sucralfate. Further research is warranted in fasted dogs and clinical cases requiring enrofloxacin or other approved fluoroquinolones in combination with sucralfate.

TGF-β cytokines increase senescence-associated beta-galactosidase activity in human prostate basal cells by supporting differentiation processes, but not cellular senescence

The family of transforming growth factors betas (TGF-betas) comprises molecules involved in growth inhibition, stress-induced premature senescence, epithelial mesenchymal transition and differentiation processes. The aim of this study was to clarify the effect of long term exposure of human prostate basal cells to TGF-betas, which are found in high concentrations in prostatic fluid and areas of benign prostatic hyperplasia (BPH). Basal cell cultures established from prostate explants (n=3) were either grown into cellular senescence, or stimulated with TGF-beta1, beta2 and beta3. Similar to cellular senescence, TGF-beta stimulation resulted in an increase of SA-beta galactosidase (SA-beta-gal) activity, flattened and enlarged cell morphology, and down-regulation of the inhibitor of differentiation Id-1. TGF-beta-treated prostate epithelial cells neither showed terminal growth arrest nor induction of important senescence-relevant genes, such as p16(INK4A), IFI-6-16, IGFBP-3 or Dkk-3. Cells stained positive for cytokeratins 8/18, but did not express other lumenal markers, such as prostate-specific antigen and androgen-receptors. TGF-betas increased also the expression of the mesenchymal marker vimentin, indicating that basal epithelial cells underwent differentiation with lumenal and mesenchymal features. In contrast, in vitro-differentiated neuroendocrine-like cells from prostate organoide cultures, expressing chromogranin A and cytokeratin 18, strongly stained positive for SA-beta-gal. Thus, SA-beta-gal activity is not only a marker for senescence, but also for differentiation of human prostate epithelial cells. With regard to the in vivo situation, in addition to cellular senescence, TGF-beta could contribute to the increased number of SA-beta-gal positive epithelial cells in BPH.

Radiation induced effect of the vitamins C, E and beta-carotene on sanazole efficiency. A study in vitro

The effect of the vitamins C, E-acetate and beta-carotene on the sanazole (AK-2123) efficiency was investigated in vitro (E. coli bacteria AB 1157) under the influence of gamma-rays. The vitamins were applied with sanazole individually or in appropriate mixtures in airfree media as well as in media saturated with nitrous oxide (N2O) or air. The addition of vitamin C led in all cases to a very strong enhancement of the sanazole efficiency, namely: in airfree media to 2-fold, in the presence of N2O to 1.5-fold and in the presence of air to 2-fold. The influence of vitamin E-acetate and beta-carotene and mixtures of them depended on the respective gas used for saturation of the medium. An attempt was made to estimate the role of the reducing (e-aq, H-atoms) and oxidizing radicals (OH, O2.-) in respect to the influence of the sanazole activity. The results are of interest for the chemoradiation therapy of cancer.

Vascular and neuroendocrine components in altered blood pressure regulation after surgical repair of coarctation of the aorta

STUDY OBJECTIVE

To investigate potential vascular and neuroendocrine determinants of altered blood pressure (BP) regulation in patients previously operated on for aortic coarctation.

DESIGN, SETTING AND PATIENTS

We prospectively re-evaluated 45 patients operated on for aortic coarctation at Strasbourg University Hospital over a 13-year period. Four of these patients were less than 2 years old at the time of the operation and four were older than 20 years. Patient age and time since the operation were on average 21+/-13 years and 8+/-3 years, respectively. Surgery consisted of a resection with end-to-end anastomosis for 18 patients, angioplasty (8), prosthesis (4) or sub-clavian flap (15).

RESULTS

Despite repair of the coarctation, about 40% of the patients showed an abnormal BP status at rest. The majority of these patients had uncomplicated borderline hypertension. The orthostasis test as well as the BP circadian rhythm were frequently abnormal. While the ankle/arm systolic pressure index measured at rest was generally within the normal range, diminished carotid-femoral pulse wave velocity was observed. Plasma adrenaline and aldosterone levels were elevated in about 50% of the patients examined.

CONCLUSIONS

These new findings suggest that there are 'cause and effect' relationships between aortic structural and functional vascular abnormalities, and augmented plasma adrenaline and aldosterone in some patients after coarctation repair. These phenomena are likely to be involved in altered BP regulation and might result in recurrent hypertension.

Determination of Platinum-Group Elements (PGE) from catalytic converters in soil by means of docimasy and INAA

The nickelsulfide fire assay (docimasy) for the enrichment of platinum-group elements (PGEs) has been modified for the use with small samples and combined with instrumental neutron-activation analysis (INAA). This procedure has been applied to the determination of PGEs exhausted from catalytic converters and deposited in soil near the Wiesbadener Kreuz (highway A3, Frankfurt-Köln). Our results show a considerable enhancement of the Pt (up to 330 ng/g), Pd (6.6 ng/g) and Rh (7.5 ng/g) contents close to the highway.

Kinematics of the Zielke procedure (VDS) in scoliosis. Intraoperative measurements

The Zielke correction technique (VDS) has two parts, derotation and ventral convex-side compression. Both were studied by measurements made during and after the operation. Ventral derotation always creates lordosis. Lordosis can be maintained during compression by insertion of intervertebral bone blocks, or kyphosis created by omitting them.

Correction of the sagittal plane in idiopathic scoliosis using the Zielke procedure (VDS)

This paper reports a retrospective review of 91 patients with idiopathic thoracic scoliosis corrected by Zielke VDS instrumentation. The results were analysed to demonstrate the correction in all three planes. Satisfactory correction was obtained, and was particularly good in the sagittal and horizontal planes. There were no disadvantages from the thoracotomy.

[Local epidemic of neonatal listeriosis in Upper Austria--report of 20 cases]

In an 8 month period, 20 cases of listeriosis among neonates were seen in the Federal District of Upper Austria. The majority of mothers reported influenza-like symptoms at the end of pregnancy. 19 cases were early-onset-infections, 6 infants developed meningitis. Serotype 1/2a was isolated in 7 cases. All were of the same phage type. 15 neonates were successfully treated with aminopenicillin or penicillin. Treatment with cephalosporin was ineffective. 4 mainly premature infants died, 1 was stillborn. There is a strong likelihood of common origin for this prenatal epidemic infection. Because of this epidemic, we recommend a listeria-effective therapy for the early-onset sepsis of the neonate.