Antimicrobial and Adjuvant Potencies of Di--alkyl Substituted Diazalariat Ethers.

Lariat ethers are macrocyclic polyethers-crown ethers-to which sidearms are appended. 4,13-Diaza-18-crown-6 having twin alkyl chains at the nitrogens show biological activity. They exhibit antibiotic activity, but when co-administered at with an FDA-approved antibiotic, the latter's potency is often strongly enhanced.

(Tryptophan) Amphiphiles Form Ion Conducting Pores and Enhance Antimicrobial Activity against Resistant Bacteria.

The compounds referred to as (tryptophan)s (BTs) have shown activity as antimicrobials. The hypothesis that the activity of these novel amphiphiles results from insertion in bilayer membranes and transport of cations is supported by planar bilayer voltage-clamp studies reported herein. In addition, fluorescence studies of propidium iodide penetration of vital bacteria confirmed enhanced permeability.

Antibiotic Potency against E. coli Is Enhanced by Channel-Forming Alkyl Lariat Ethers.

Several N,N'-bis(n-alkyl-4,13-diaza[18]crown-6) lariat ethers were found to significantly enhance the potency of rifampicin and tetracycline, but not erythromycin and kanamycin, against the non-pathogenic DH5α and K-12 strains of Escherichia coli when administered at levels below their minimum inhibitory concentrations (MICs). The enhancements in antibiotic potency observed for the lariat ethers ranged from three- to 20-fold, depending on the strain of E. coli, the antibiotic, and the lengths of the alkyl chains attached at the macroring nitrogen atoms.

Hydraphiles enhance antimicrobial potency against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis.

Hydraphiles are synthetic amphiphiles that form ion-conducting pores in liposomal membranes. These pores exhibit open-close behavior when studied by planar bilayer conductance techniques. In previous work, we showed that when co-administered with various antibiotics to the DH5α strain of Escherichia coli, they enhanced the drug's potency.

An aggressive systemic juvenile xanthogranuloma clonally related to a preceding T-cell acute lymphoblastic leukemia.

Juvenile xanthogranuloma (JXG) is a disorder of disputed origin thought to be related to the dermal/interstitial macrophage. A 5-year-old female presented with an aggressive systemic JXG that developed 5 months after the diagnosis of T-cell acute lymphoblastic leukemia (T-ALL). Examination of the T-cell receptor gamma (TCR-γ) rearrangement in T-ALL blasts, JXG infiltrated lymph node biopsies and micro-dissected JXG histiocytes revealed an identical bi-allelic TCR-γ rearrangement in all samples, thus providing evidence for a clonal relationship between T-ALL and JXG in this case.

[Solitary synchronous intraocular metastasis of a peripheral non-small cell lung cancer : A multidisciplinary approach with curative intention].

A solitary synchronous distant metastasis of newly diagnosed non-small cell lung cancer (NSCLC) occurs in only a small number of patients. The available literature suggests a significant rise in long-term survival for these patients when resection of the bronchial carcinoma and the metastasis are feasible and performed. To demonstrate a multidisciplinary concept, we present the case of a patient with a peripheral NSCLC and a solitary synchronous intraocular metastasis.

Cowpox virus infection in pet rat owners: not always immediately recognized.

Background: The aim of this article is to make physicians of all specialties aware of the possible variations of clinical course in human cowpox infection. This has been a matter of current interest since the detection of a first cluster of infections among owners of white pet rats in the Krefeld area in the spring of 2008. Two further cases arose in the Krefeld area in November 2008, and there have since been multiple further reports from various regions in Germany and the neighboring countries.

The Influence of Varied Amide Bond Positions on Hydraphile Ion Channel Activity.

Hydraphile compounds have been prepared in which certain of the amine nitrogens have been replaced by amide residues. The amide bonds are present either in the sidearm, the side chain, or the central relay. Sodium cation transport through phospholipid vesicles mediated by each hydraphile was assessed.

Correlation of bilayer membrane cation transport and biological activity in alkyl-substituted lariat ethers.

Dialkyldiaza-18-crown-6 lariat ethers having twin n-octyl, n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl, 1-oxodecyl and 1-oxododecyl side arms were prepared and studied. Cation transport in liposomes mediated by these compounds showed discontinuous activity that correlated with toxicity to the bacteria E. coli and B.

Hyperacute rejection in an ex vivo model of renal xenografting. Role of the mediator response and its pharmacologic manipulation by the specific platelet-activating factor antagonist WEB 2086BS.

The pharmacologic modulation of the platelet-activating factor antagonist WEB 2086BS on the release of metabolites of the arachidonic acid and the cytokine TNF alpha was investigated in an ex vivo xenograft model of hyperacute rejection. Pig kidneys were perfused for 60 min in a perfusion system with oxygenated heparinized human or autologous porcine blood, respectively. During autologous perfusion, no alterations in the mediator response could be detected, whereas xenogeneic perfusion induced progressive release of mediators.

Distribution of cell adhesion molecules (ICAM-1, VCAM-1, ELAM-1) in renal tissue during allograft rejection.

The tissue distribution of cellular adhesion molecules (CAMs) was studied in specimens from 10 normal human kidneys and in 52 biopsies from kidney allografts with cell-mediated rejection. In addition to the vascular presence of ICAM-1, a common finding in normal kidneys, expression of ICAM-1 on tubular cells was observed in 22 graft biopsies. Compared with normal kidneys, where VCAM-1 was present on Bowman's capsules and few proximal tubular cells, a markedly enhanced expression of VCAM-1 in numerous tubuli (including distal tubular segments) was observed in 51 graft biopsies.

Biophysical parameters of radiofrequency catheter ablation.

Radiofrequency catheter ablation has been shown to be an effective treatment for patients with accessory pathways in Wolff-Parkinson-White syndrome and other supraventricular tachycardias. However, the biophysical parameters used so far in vivo did not correlate to the size of myocardial lesions and provided no information about the myocardial wall contact of the electrode. In this study 104 radiofrequency applications were performed on excised pig myocardium in circulating heparinized pig blood as well as in blood alone, and root mean square (rms) voltage, root mean square current and phase angle were measured using a specially developed device.

[Importance of physical parameters for the effectiveness of radiofrequency catheter ablation].

Radiofrequency catheter ablation has been shown to be an effective form of treatment of accessory pathways in patients with WPW-syndrome and other supraventricular tachycardias. However, the biophysical parameters so far used in vivo neither correlated with the size of the myocardial lesion nor did they provide any information about contact of the electrode with the myocardial wall. In this study, 104 radiofrequency energy applications were performed on excised pig myocardium in circulating heparinized pig blood, and in blood alone, and root mean square (rms) voltage, current and phase angle were measured using a specially developed device.

Tumoral calcinosis of the ischium.

The authors report on a case of tumoral calcinosis of the ischium in a 63-year-old female. By means of this particular case a general review of the literature on pathogenesis, histological characteristics, the possible way of treatment and the prognosis of tumoral calcinosis is presented.

Vascular deposition of complement-split products in kidney allografts with cell-mediated rejection.

Complement activation in 73 renal transplant biopsies was investigated by indirect immunoperoxidase staining using MoAbs reactive with complement-split products. Intense deposition of complement fragments C4d and C3d in peritubular capillaries, indicating activation of the classical pathway, could be detected in the majority of transplanted kidneys with cell-mediated rejections. Abundant deposition of complement-split products was observed in 22 early biopsies from patients with high 'immunological risk' (i.

Carcinoma of the breast and heart transplantation: a case report.

A 35-year-old woman underwent heart transplantation in 1986 because of dilated cardiomyopathy that developed after mitral valve replacements in 1971, 1975, and 1982. Additionally, a carcinoma of the left breast was diagnosed in 1984, leading to mastectomy, and in 1985 a local recurrent tumor had to be resected. In 1988 her gallbladder was removed after repeated episodes of biliary colic.

Mediastinitis and mycotic aneurysm of the aorta after orthotopic heart transplantation.

After cardiac transplantation, bacterial mediastinitis is a rare but dangerous early complication. Of the 113 patients who underwent heart or heart-lung transplantation at our hospital from August 1981 to April 1989, 8 developed purulent mediastinitis. Treatment involved surgical débridment, local irrigation, drainage, and high-dose systemic antibiotics.

[Echocardiographic diagnosis of acute graft rejection in heart transplant patients under cyclosporin therapy].

Though endomyocardial biopsy has remained the gold standard for diagnosing acute cardiac rejection (AR), this invasive method does not provide adequate means for close monitoring of the rejection process. In order to assess the usefulness of M-Mode- and two-dimensional (2D) echocardiography for the noninvasive diagnosis of AR in heart transplant recipients on cyclosporin, 45 patients (mean age 40.6 +/- 8.