Search PubMed⌕ Search

Biomedical subjects

G Jost

Publications and source records attributed to G Jost.

At least 19 recordsLinked to original sources

Antiseptic efficacy of a low-dosed topical triclosan/chlorhexidine combination therapy in atopic dermatitis.

The topical application of triclosan as an antistaphylogenic antiseptic has proven beneficial in atopic dermatitis. Especially in lipophilic carriers, triclosan is applied in a concentration range between 1 and 5%, usually 2%. However, as a phenol, triclosan is not undisputed and may result in local exacerbation of the disease by eliciting irritative secondary reactions, especially in high concentrations. Chlorhexidine is also an antiseptic which is very effective against Staphylococci and nearly equivalent to triclosan with respect to its antistaphylogenic efficacy. In light of this, the combination of the two active substances in very low concentrations offers a possible option of using the additive effects of the two substances to minimize the risk of side effects. In a uniform W/O emulsion carrier alternatively containing 0.3% triclosan combined with 0.34% chlorhexidine dihydrochloride or 2.0% triclosan, the antibacterial efficacy against Gram-positive skin bacteria could be proven in a preclinical comparison with a reference preparation containing fusidic acid. Subsequently, the pathogen-reducing effect was examined in a clinical study of the influence on clinical severity in patients with atopic dermatitis. Both investigation methods showed that the two test preparations were slightly inferior to the reference preparation, but result in the same degree of pathogen reduction and improvement in the severity of existing atopic dermatitis in direct comparison. The overall results support the conclusion that a combination of triclosan and chlorhexidine in low concentrations as well as the existing antiseptic standard of a 2% triclosan preparation are suitable for pathogen reduction and thus for improving atopic dermatitis.

Adolescent↗

Resection of thoracic dumbbell neurinomas: single postero-lateral approach or combined posterior and transthoracic approach?

Dumbbell tumours are those with an intraspinal and a paraspinal component, connected through a frequently enlarged and eroded intervertebral foramen. Most dumbbell tumours are located in the thoracic spine, and most of them are schwannomas. The extraspinal tumour extension is usually larger than the intraspinal tumour part, but the intraspinal tumour component commonly causes the typical symptoms: local pain and symptoms from spinal cord compression in the thoracic spine. Diagnosis is best established by magnetic resonance imaging with and without contrast agent injection. Controversy exists as to whether to remove thoracic dumbbell tumours using a single posterior approach with posterolateral extension or using a combined posterior and transthoracic approach. We report the removal of a dumbbell neurinoma at T6/7 using a single posterior midline approach with laminectomy and costo-transversectomy and review the literature regarding the approaches to thoracic dumbbell tumours.

Humans↗

[Magnetic resonance spectroscopy of brain tumours].

Magnetic resonance spectroscopy facilitates non-invasive determination of metabolic changes in vivo. The main metabolites are the neuronal marker N-acetylaspartate (NAA), cholines reflecting membrane turnover, creatine, lactate, and mobile lipids. Primary brain tumours exhibit reduced NAA and increased choline resonances compared to normal brain, and these abnormalities increase with higher malignancy. Increasing choline resonances on follow-up studies correlate with tumour progression, whereas the reduction of initially increased choline resonances indicates a transition from viable tumour to necrotic tissue. Metastases as non-neuroectodermal tumours lack NAA, but demonstrate elevated choline, lactate and lipid resonances. Lymphomas are characterised by massively increased lipid resonances with markedly elevated choline. Prominent alanine resonances are often observed in meningioma. Cystic/necrotic lesions demonstrate elevated lactate regardless of their aetiology. The characteristic finding of prominent resonances from acetate, succinate, and alanine, of leucine, isoleucine and valine in untreated bacterial abscesses allows the differentiation of bacterial abscesses from cystic/necrotic brain tumours.

Biomarkers, Tumor↗

[Current use and possible future applications of the magnetization transfer technique in neuroradiology].

Magnetization transfer (MT) imaging is a special MR technique used for selective suppression of the MR signal of protons bound on macromolecules. The most important applications in neuroradiology are (1) detection of subtle changes in otherwise normal-appearing cerebral white matter, for instance in multiple sclerosis (MS), Wallerian degeneration, and hydrocephalus, (2) differentiation of white matter lesions with high signal on T (2)-weighted MR-images, like MS plaques, brain infarctions, and brain edema, (3) follow-up of cerebral white matter diseases using volumetric MT techniques, and (4) improvement in delineating of contrast enhancing brain lesions, such as cerebral metastases. We describe the physical rationale of the MT technique and present the most important current and possible future applications of MT imaging to answer clinical and scientific questions in neuroradiology.

AIDS Dementia Complex↗

[Comparison of a sulfate-free polyethylene glycol (PEG) solution with a standard solution for colonoscopy preparation].

In order to ameliorate the unpleasant salty taste of a standard PEG-electrolyte lavage solution and thus improving acceptance of colonoscopy cleansing, a new sulfate-free, low sodium PEG-solution has been developed as long as 10 years ago. Comparative studies regarding acceptance showed conflicting results. This study was intended to compare the standard solution L (Cololyt) with the sulfate-free solution S (Colo-Sol) on a prospective basis in a collective of average gastroenterology outpatients. The 144 patients who underwent colonoscopy ingested 1 liter of solutions L and S each on the evening before and another liter of the preferred solution (preference) in the morning of the day of examination. Moreover the taste of both solutions was rated (grading scale 0-10). Tolerance and efficacy were registered as well. Preference and thus acceptance presented very well-balanced. Solution L was preferred as frequent (by 50.7% of patients) as solution S (49.3%) which was originally claimed to be better tasting. The respective preferred solutions were rated equal with mean +/- SD values of 6.6 +/- 2.2 for L and 7.0 +/- 1.9 for S. Efficacy and tolerance did not differ from a clinical point of view.

Administration, Oral↗

Molecular analysis of ammonia oxidation and denitrification in natural environments.

This review summarizes aspects of the current knowledge about the ecology of ammonia-oxidizing and denitrifying bacteria. The development of molecular techniques has contributed enormously to the rapid recent progress in the field. Different techniques for doing so are discussed. The characterization of ammonia-oxidizing and -denitrifying bacteria by sequencing the genes encoding 16S rRNA and functional proteins opened the possibility of constructing specific probes. It is now possible to monitor the occurrence of a particular species of these bacteria in any habitat and to get an estimate of the relative abundance of different types, even if they are not culturable as yet. These data indicate that the composition of nitrifying and denitrifying communities is complex and apparently subject to large fluctuations, both in time and in space. More attempts are needed to enrich and isolate those bacteria which dominate the processes, and to characterize them by a combination of physiological, biochemical and molecular techniques. While PCR and probing with nucleotides or antibodies are primarily used to study the structure of nitrifying and denitrifying communities, studies of their function in natural habitats, which require quantification at the transcriptional level, are currently not possible.

Ammonia↗

[Colonic preparation with sodium phosphate. Prospective, randomized, placebo-controlled double blind study with various antiemetics].

UNLABELLED: The well established bowel cleansing method using a polyethylene glycol-based solution (Fordtran) is limited by the necessity of large volume intake, which proves difficult for many patients. Therefore, a new method using small volumes (2 x 90 ml) of oral sodium phosphate is employed more and more frequently. Its only disadvantage is the occurrence of considerable nausea or occasional vomiting in about 25% of patients. To ascertain whether nausea could be reduced, 426 patients were given an antiemetic (ondansetron, metoclopramide, cisapride) or placebo on a randomized, double-blind basis, one hour before sodium phosphate intake. RESULTS: sodium phosphate was well tolerated in 69.2% of the patients on placebo, 73.6% on cisapride, 76.5% on metoclopramide and 80.4% on ondansetron. Taking all four groups together, male patients exhibited much better tolerance (86.1%) than females (66.1%). Severe nausea and/or emesis was noted in 22.4% of patients on placebo, 21.7% on cisapride, 17% on metoclopramide and 14% on ondansetron. In over 90% of patients colon cleansing was rated as good to very good. This was largely independent of the severity of nausea. 129 patients who had undergone former polyethylene glycol-based lavage judged sodium phosphate to be more tolerable and easier to complete. Considering known contraindications (symptomatic congestive heart failure and/or renal failure), no serious adverse event was noted in any of the 426 patients investigated. In accordance with several recent studies, we consider sodium phosphate solution at present the procedure of choice for colon cleansing. Compared to Fordtran, patient acceptance is far better and cleansing quality superior. Routine antiemetic comedication for reducing possible nausea/vomiting is not worthwhile. On the other hand, this study confirms our former impression of enhanced colon cleansing after administration of an additional mild laxative before sodium phosphate, without interfering with patient acceptance.

Administration, Oral↗

Ciprofloxacin pharmacokinetics in burn patients.

Many drugs exhibit altered pharmacokinetic parameters in burn patients. We prospectively evaluated the pharmacokinetics of ciprofloxacin in eight burn patients with active infections. Each patient received a 400-mg dose of ciprofloxacin intravenously (i.v.) every 8 h, with each dose infused over 1 h by using a rate control device. Blood samples for analysis of plasma ciprofloxacin concentrations, determined by high-performance liquid chromatography, were obtained immediately predose, at the end of the infusion, and 1, 2, 3, 4, 5, 6, and 7 h after the end of the infusion. Urine was collected from 0 to 2, 2 to 4, and 4 to 8 h following the same dose, and an aliquot was saved for determination of the ciprofloxacin concentration. Urine was also collected for 24 h prior to this dose for measurement of creatinine clearance (CLCR). Pharmacokinetic parameters were estimated by noncompartmental analysis. Mean maximum and minimum plasma ciprofloxacin concentrations were 4.2 +/- 1.1 and 0.70 +/- 0.55 microgram/ml, respectively. Mean values for clearance (CL), renal clearance (CLR), volume of distribution, terminal elimination rate constant, half-life (t1/2), and area under the concentration-time curve (AUC) were 29.1 +/- 17.5 liters/h, 13.5 +/- 10.1 liters/h, 1.75 +/- 0.41 liters/kg, 0.222 +/- 0.098 h-1, 4.5 +/- 3.9 h, and 20.7 +/- 16.6 micrograms.h/ml, respectively. CL was higher and t1/2 was shorter than noted in previous studies of acutely ill, hospitalized patients. A good correlation was noted between creatinine clearance CL(CR) and both total ciprofloxacin CL (r = 0.85) and CLR (r = 0.84). A moderate inverse correlation was noted between percent body surface area burned and total ciprofloxacin CL (r = -0.55). An AUC/MIC ratio above 125 SIT-1 (where SIT is serum inhibitory titer), which has been strongly correlated with clinical response and time to bacterial eradication, was achieved in five of eight patients (63%) with a MIC of 0.25 microgram/ml. At a ciprofloxacin dosage of 400 mg i.v. every 12 h, an AUC/MIC ratio above 125 SIT-1 would have been achieved in only two of eight patients (25%). We conclude that ciprofloxacin CL is highly variable, but generally increased, in burn patients compared with that in acutely ill, general medical and surgical patients. Because of an increase in CL, a ciprofloxacin dosage of 400 mg i.v. every 8 h is more likely to produce the desired response in burn patients than the same dose given every 12 h.

Adolescent↗

[Helicobacter pylori eradication therapy with bismuth citrate/amoxycillin combination therapy].

The efficacy of a new combination preparation containing bismuth citrate and amoxicillin in one tablet was compared with the efficacy of bismuth citrate monotherapy in a randomised double-blind study on the eradication of Helicobacter pylori. The study involved 70 H. pylori positive (antrum biopsies showing a positive urease test) patients with non-ulcer dyspepsia and chronic gastritis. The treatment period was 14 days; 35 patients in group 1 received 2 tablets tid containing the bismuth citrate amoxicillin combination (BIAM tablet; 250 mg amoxicillin base and 120 mg bismuth); 35 patients in group 2 were treated with 2 tablets tid containing bismuth citrate (BI tablet; 120 mg bismuth). Total daily dose was therefore 1500 mg amoxicillin + 720 mg bismuth in group 1 patients resp. 720 mg bismuth in group 2 patients. 4 weeks after therapy H. pylori could not be histologically detected in the antrum of 22 patients (63%) in group 1 and 8 patients (24%) in group 2. Thus in group 1 (BIAM) a significantly higher eradication rate (p < 0.001) was shown than in group 2 (BI). Inflammation characterized by the infiltration of polymorphonuclear cells was significantly (p < 0.01) less pronounced in group 1 (BIAM) than in group 2 (BI) 4 weeks after the end of treatment. Gastrointestinal distress was quantified by evaluation of 13 different symptoms using a fourpoints scale at the beginning of the study and after 2 and 6 weeks. The sum of scores decreased by 81% in group 1 (BIAM) and 71% in group 2 (BI) after 6 weeks.

Adult↗

Subfascial lifting.

The authors demonstrate by anatomical dissection that inaccuracies made by classical anatomists have worried plastic surgeons for many years. They demonstrate that continuity between the parotid fascia and the fibrous platysma has not been recognized. In addition, anatomists in the past have not been aware that the platysma is a unique type of fasciomuscular layer because in contrast to conventional anatomical opinions, the platysma has no bony attachment to the mandible.

Face↗

[Use of polytetrafluoroethylene (Gore-Tex E-PTFE Soft Tissue Patch) for suspension of former facial paralysis and as reconstructive tissue].

The insertion of autogenous fascia lata to suspend the paralyzed cheek and lips remains one of the most widely practiced procedures in correction of long term paralysis of the lower facial muscles. For 34 months we used thin layers (1 mm) of expanded polytetrafluoroethylene (E-PTFE Gore-Tex Soft Tissue Patch) to replace autogenous fascia lata, in 20 patients, with satisfactory results. 13 patients were treated by classical techniques of insertion-suspensions of the paralyzed side with a perioral loop and slings of PTFE suspended to the zygomatic arch and the infraorbital rim, by way of nasolabial angle or rhytidectomy incisions. In 7 patients, an eyelid suspension was performed with PTFE by Arion's technique, but by replacing the classical silicon thread by E-PTFE and transposing the medial part of the temporalis muscle on the external canthus, and fixing the lateral end of the sling to the muscle. This technique assures a good corneal coverage with healing of the previous ulceration and allows a voluntary occlusion of the eyelids. The PTFE soft tissue is notably successful as an implant. This biocompatible material shows excellent tissue tolerance, the porous microstructure encouraging tissue attachment and infiltration. E-PTFE holds its shape, resists to infection, and permits a notably reduction of the hospitalization because it avoids a second surgical site. We have experience of the material as a reconstructive substance in 6 cases of either bone or subcutaneous deficits, where no other satisfactory solution was available. Is these cases our follow-up is 18 months.

Biocompatible Materials↗

Effect of liver function on the metabolism of prednisone and prednisolone in humans.

The systemic availability of total prednisone and unbound prednisolone, and the urinary excretion of 6 beta-hydroxyprednisolone, were measured after an oral dose of prednisone and an i.v. dose of prednisolone in 22 patients covering a wide range of liver function (galactose elimination capacity ranging from 3.3 mg/min X kg body wt to 9.2 mg/min X kg body wt). The area under the plasma concentration versus time curves of prednisolone and of prednisone decreased with increasing galactose elimination capacity. This dependency of the steroid concentrations on liver function was attributed to a decreased metabolic clearance and not to an increased systemic availability of the steroid given p.o. in patients with impaired liver function. The fractional excretion and the fractional clearance of 6 beta-hydroxyprednisolone declined with decreasing metabolic clearance rate of prednisolone or with decreasing galactose elimination capacity. Thus, the enzymes involved in the 6 beta-hydroxylation are not spared as liver function declines, and the exposure to the biologically active unbound prednisolone is increased in patients with impaired liver function in relation to the amount of prednisone or prednisolone administered.

Adult↗

Effect of dietary caffeine on airway reactivity in asthma.

The potential influence of dietary caffeine on bronchoprovocation challenges with carbachol was examined in 7 patients with asymptomatic asthma. In a double-blind fashion placebo or caffeine (6 mg/kg body weight; equivalent to approximately 4 cups of coffee) solved in orange juice was administered, and carbachol challenges were performed. The average peak serum concentration achieved 60 min after dosing was 7.6 +/- SD 2.1 mg/l. These caffeine levels did not produce any appreciable attenuation of the bronchoconstrictor response to carbachol inhalations. It thus appears that dietary caffeine is barely a cause of erroneous interpretations of bronchoprovocation challenges with carbachol.

Administration, Oral↗

[Nasal reconstruction using the Converse frontal flap or a Washio retroauricular flap. Technical notes].

14 cases of nasal reconstruction by the Converse Scalping Flap or the Washio Temporo-auricular flap technique, over three years, led us to point out details necessary to insure the quality of the results. In particular, the Converse Flap must be thin; it never needs bone neither cartilage reinforcement when used in reconstructions of the two inferior third of the nose. The pedicle weaning method described allows the replacement of the scalp on thirteenth day. New data for the Washio technique are as following: --The mastoidian skin and not the retro-auricular skin must be used; --The back-cut of the scalp follows the AC line dating from three fixed points: A = helix root B = end of incision on the frontal hairline vertically to the fronto-orbital suture, and AB = AC = BC. This new data seem to warrant the fiability of the Washio flap, however the latter cannot dethrone the Converse flap, king flap of medio-facial reconstructions.

Humans↗