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1.
During recent decades there has been a controversial discussion if comparable plasma level profiles which are rather constant or those which show a high peak are more efficient for the cure of gonorrhoea. So far, investigations in this field were not based on the Grasso apparatus. Although the findings with cefotiam and ceftizoxime do not allow to formulate a general hypothesis without any restriction, it can be stated that on the basis of an identical area under the antibiotic level time curve, 'peak concentration' profiles are more favourable.  相似文献   
2.
With topical treatment of skin diseases, the requirement of a high and reproducible drug uptake often still is not met. Moreover, drug targeting to specific skin strata may improve the use of agents which are prone to cause local unwanted effects. Recent investigations have indicated that improved uptake and skin targeting may become feasible by means of nanoparticular systems such as solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions (NE). Here we describe techniques to characterize drug loading to carrier systems and skin penetration profiles by using the lipophilic dye nile red as a model agent. Since the mode of drug association with the particle matrix may strongly influence the efficiency of skin targeting, parelectric spectroscopy (PS) was used to differentiate between matrix incorporation and attachment to the particle surface and fluorescence spectroscopy (FS) to solve dye distribution within NLC particles. Nile red was incorporated into the lipid matrix or the covering tensed shell, respectively, of SLN and NLC with all the lipids studied (Compritol, Precirol, oleic acid, Miglyol). In NLC, the dye was enriched in the liquid phase. Next, nile red concentrations were followed by image analysis of vertical sections of pigskin treated with dye-loaded nanoparticular dispersions and an oil-in-water cream for 4 and 8 h in vitro. Following the SLN dispersions, dye penetration increased about fourfold over the uptake obtained following the cream. NLC turned out less potent (相似文献   
3.
Both cefotiam and ceftizoxime stimulate the uptake of gonococci by polymorphonuclear granulocytes in vitro as can be seen by light microscopy. Although this already holds true of antibiotic concentrations lower than the minimum inhibitory concentration (MIC: 1/4 x) this effect is much more marked at concentrations highly exceeding the MIC (4000 x). As light microscopic investigation allows the analysis of large numbers of cells but no final judgement on actual bacterial engulfment definite phagocytosis is demonstrated by electron microscopy.  相似文献   
4.
A 25-year-old homosexual black male presented with asymmetrical perianal ulceration of uncertain clinical origin. Indepth microbiological examination revealed the combined presence of Haemophilus ducreyi and Treponema pallidum. The atypical clinical appearance may have been due to the changed immunological status of the host's being infected with Human Immunodeficiency Virus.  相似文献   
5.
Summary Although cryostat sections in general allow a distinction to be made between malignant melanomas and other pigmented lesions in clinically doubtful cases, the differential diagnosis may be difficult. The histological and cytological criteria taken into account can be classified as major, minor, and insufficient. Knowing the diagnostic value of each makes a conventionally established diagnosis safer. Variance analysis does not contribute to the problem but it can nevertheless be shown that the evaluation of six major criteria makes a quick and reliable cryostat section diagnosis possible. If these results are confirmed in a prospective study it would be a decisive step on the way to a quicker and safer cryostat section diagnosis of malignant melanoma, even for the less experienced histopathologist.The results published here were presented in part at the DDG meeting 1980 at Westerland/SyltWe are grateful to Miss Schubert, Institute of Biomathematics of the University of Munich, for the statistical evaluations  相似文献   
6.
Human defensins   总被引:7,自引:0,他引:7  
Antimicrobial peptides are small, cationic, amphiphilic peptides of 12–50 amino acids with microbicidal activity against both bacteria and fungi. The eukaryotic antimicrobial peptides may be divided into four distinct groups according to their structural features: cysteine-free -helices, extended cysteine-free -helices with a predominance of one or two amino acids, loop structures with one intramolecular disulfide bond, and -sheet structures which are stabilised by two or three intramolecular disulfide bonds. Mammalian defensins are part of the last-mentioned group. The mammalian defensins can be subdivided into three main classes according to their structural differences: the -defensins, -defensins and the recently described -defensins. Mammalian -defensins are predominantly found in neutrophils and in small intestinal Paneth cells, whereas mammalian -defensins have been isolated from both leukocytes and epithelial cells. Recently, two novel human -defensins, human beta-defensin-3 (HBD-3), and human beta-defensin-4 (HBD-4) have been discovered. Similar to HBD-1 and HBD-2, HBD-3 has microbicidal activity towards the Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and the yeasts Candida albicans and Malassezia furfur. In addition, HBD-3 kills Gram-positive bacteria such as Streptococcus pyogenes or Staphylococcus aureus, including multi-resistant S. aureus strains, and even vancomycin-resistant Enterococcus faecium. In contrast to HBD-1 and HBD-2, significant expression of HBD-3 has been demonstrated in non-epithelial tissues, such as leukocytes, heart and skeletal muscle. HBD-4 is expressed in certain epithelia and in neutrophils. Its bactericidal activity against P. aeruginosa is stronger than that of the other known -defensins. Here we present an overview of human antimicrobial peptides with some emphasis on their antifungal properties.J.J. Schneider and A. Unholzer contributed equally to this work  相似文献   
7.
Today, the term "normal skin pH" is understood to be the pH value of the surface of the skin of the lower arm of a healthy adult male Caucasian. Its mean value lies in the range 5.4-5.9. In most cases, it is determined by means of a flat glass electrode. The parameter "skin pH" depends mainly on the area of skin and on age, but it also depends to a lesser extent on sex, race and the time of day when values are determined.  相似文献   
8.
Summary The anti-inflammatory activity of hamamelis distillate has been evaluated with respect to drug concentration (0.64 mg/2.56 mg hamamelis ketone/100 g) and the effect of the vehicle (O/W emulsion with/without phosphatidylcholine (PC) in an experimental study. The effects were compared with those of chamomile cream, hydrocortisone 1% cream and 4 base preparations. Erythema was induced by UV irradiation and cellophane tape stripping of the horny layer in 24 healthy subjects per test. Skin blanching was quantified by visual scoring and chromametry. Drug effects were compared with one another and with an untreated control area, as well as with any action due to the vehicle.UV-induced erythema at 24 h was suppressed by low dose hamamelis PC-cream and hydrocortisone cream. Hydrocortisone appeared superior to both hamamelis vehicles, hamamelis cream (without PC) and chamomile cream. The latter preparation was also less potent than hamamelis PC-cream. Erythema 4 to 8 h after the stripping of the horny layer was suppressed by hydrocortisone (P0.05). Inflammation was also less pronounced following low dose hamamelis PC-cream and chamomile cream. Hamamelis PC-cream, however, appeared less potent than hydrocortisone. In general, visual scoring was more discriminatory than chromametry.The results have demonstrated an anti-inflammatory activity of hamamelis distillate in a PC-containing vehicle. A fourfold increase of drug concentration, however, did not produce an increase in activity.  相似文献   
9.
A novel plasmid of about 7.8 megadaltons (MDal) could be detected in a non-penicillinase-producing Neisseria gonorrhoeae strain isolated in Munich in 1987. As the strain showed no resistance against commonly used chemotherapeutic agents, at present the plasmid must be described as phenotypically cryptic.Corresponding author.  相似文献   
10.
Purpose. Pharmacodynamic characterization of topical glucocorticoids as prednicarbate (PC), its metabolites prednisolone 17-ethylcarbonate (PEC) and prednisolone (PD), betamethasone 17-valerate (BMV), beta-methasone (BM) and desoximetasone (DM) by evaluating their effects on epidermal and dermal cells. Synopsis of pharmacokinetic and pharmacodynamic studies, possibly explaining the improved benefit-risk ratio of prednicarbate. Methods. Isolated foreskin keratinocytes were used to investigate the influence on epidermal inflammatory processes, dermal fibroblasts of the same origin to study antiproliferative activities of glucocorticoids. Interleukins were measured by ELISA-assay, the influence on II-l-production also on mRNA-level by RNAse protection assay. Proliferation was assessed by 3H thymidine incorporation and biodegradation by HPLC/UV-absorption. Cell viability was controlled by MTT assay. Results. In keratinocytes, inflammation was induced by TNF, resulting in an increased II- l synthesis. This cytokine was particularly suppressed by PC and BMV, whereas PEC, PD, DM and BM were less potent (p 0.05). Since, however, the double ester PC is rapidly degraded in keratinocytes, a RNAse-protection assay of II-1 mRNA was performed allowing short incubation times and thus minimizing biodegradation effects. In agreement with the previous experiment, the antiinflammatory potency of native PC was confirmed. In fibroblasts, II-l and II-6 synthesis indicate proliferation and inflammation respectively. Whereas PC inhibited II- l and II-6 production in fibroblasts to a minor extent only, it was strongly reduced by the conventional glucocorticoids and PEC (p 0.05). The minor unwanted effect of PC on fibroblasts was also reflected by its low influence on cell proliferation as assayed by 3H thymindine incorporation. More pronounced antiproliferative features were observed with BM, PEC and espectially BMV. Conclusions. Correlating antiphlogistic effects in keratinocytes (suppression of II-l) with antiproliferative effects in fibroblasts (suppression of II-l and II-6), the improved benefit–risk ratio of PC compared to conventional glucocorticoids does not result only from distinct drug metabolism in the skin but also from a specific influence on the cytokine network.  相似文献   
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