Antileukoprotease in human skin: an antibiotic peptide constitutively produced by keratinocytes

Antileukoprotease (ALP), also known as mucous protease inhibitor or secretory leukoprotease inhibitor, resembles one of the major antiproteases present in human body fluids. It is capable of preventing proteolytic degradation of extracellular matrix proteins by neutrophil-derived serine proteases. ALP was isolated from human callus and detected in supernatants of cultured human primary keratinocytes. ALP mRNA was constitutively expressed in keratinocytes and the expression was not significantly affected by TNF alpha or Interferon gamma stimulation. In microbicidal assays recombinant ALP exhibited antimicrobial activity against several human skin associated microorganisms like P. aeruginosa, S. aureus, S. epidermidis, and C. albicans, indicating that ALP may actively participate in mechanisms allowing homeostasis of bacterial and yeast colonization on human skin. Thus, ALP represents a major soluble serine protease inhibitor and antimicrobial agent expressed in human skin and seems to contribute to the high resistance of the epidermis against proteolysis and infections.     

Persistence of PCR-detectable Bacteroides distasonis from human feces in river water

To evaluate the persistence of PCR-detectable Bacteroides distasonis in surface water, whole human feces were dispersed into water from the Ohio River and incubated in flasks in the laboratory or in diffusion chambers in situ. Duplicate samples were taken daily, and material that pelleted at 16,000 x g was assayed by PCR. Persistence of PCR-detectable DNA from this anaerobe depended upon temperature and predation, two of the factors shown by others to influence the survival of aerobic bacteria detected by culture. B. distasonis was detected by PCR for at least 2 weeks at 4 degrees C but for only 4 to 5 days at 14 degrees C, 1 to 2 days at 24 degrees C, and 1 day at 30 degrees C. In filtered water or in the presence of cycloheximide, a eukaryotic inhibitor, persistence at 24 degrees C was extended by at least a week.     

Isolation of an atypical Pasteurella-like organism from guinea pig abscesses

The action of eserine of acetylcholinesterase (AchE) reversible inhibitor of frog muscle fibres membrane potential (MP) under various physico-chemical conditions in external solution was studied. The data obtained show that changes of external pH in any direction decrease the depolarisation of the membrane produced by eserine. The dose-effect curve is linear at pH 7, but it has saturation at pH 6 and pH 9. Dependence of the membrane depolarisation in the presence of eserine upon calcium ions concentration in external solution is S-shape. Protonophore 3C1CCP (carbonilcianamid-m-3C1-phenylhydrazon) depolarises the membrane further in the presence of eserine. Valinomycin under these conditions completely restores the MP. Evidence is obtained that eserine reduces potassium permeability of the muscle membrane. It is supposed that membrane-bound AchE is involved in the ionic permeability regulation of the muscle membrane at rest.     

Production of inflammatory mediators by human macrophages obtained from ascites

Ascites is a readily available source of human macrophages (M phi), which can be used to study M phi functions in vitro. We characterized the mediators of inflammation produced by human peritoneal M phi (hp-M phi) obtained from patients with portal hypertension and ascites. The production of the cytokines interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) was found to be lipopolysaccharide (LPS) concentration dependent (0-10 micrograms/ml) with a maximal production at 10 micrograms/ml and also dependent on the time of exposure to the stimulus (0-36 h). IL-1 beta, IL-6 and TNF-alpha production after LPS administration reached a plateau at 24 h. In vitro stimulation for 24 h with LPS does not influence the eicosanoid production from endogenous arachidonate. 13 min of exposure of the cells to the calcium ionophore A23187 gives a significant increase in eicosanoid production from both exogenous and endogenous arachidonate. The main eicosanoids produced are the 5-lipoxgenase products LTB4 and 5-hydroxyeicosatetraenoic acid (HETE). The increase in production of the other eicosanoids is not significant. The eicosanoid production depends on the stimulus concentration. The optimal A23187 concentration is 1 microM. Oxygen radical production was measured in the M phi by a flowcytometric method. The fluorescence intensity of phorbol 12-myristate 13-acetate stimulated and dihydro-rhodamine 123 loaded hp-M phi increases significantly after 15 min. We conclude that LPS stimulation of hp-M phi from liver disease results in similar production of IL-1 beta, IL-6 and TNF-alpha, but that the profile of the eicosanoid production of these M phi stimulated with LPS and A23187 differs from M phi of other origin and species.     

Production of beta-defensins by human airway epithelia

Human beta-defensins (HBDs) are antimicrobial peptides that may play a role in mucosal defense. Diminished activity of these peptides has been implicated in the pathogenesis of cystic fibrosis (CF) lung disease. We show that HBD-1 and HBD-2 mRNAs are expressed in excised surface and submucosal gland epithelia from non-CF and CF patients. The pro-inflammatory cytokine interleukin-1beta stimulated the expression of HBD-2 but not HBD-1 mRNA and peptide in primary cultures of airway epithelia. HBD-1 was found in bronchoalveolar lavage (BAL) fluid from normal volunteers, CF patients, and patients with inflammatory lung diseases, whereas HBD-2 was detected in BAL fluid from patients with CF or inflammatory lung diseases, but not in normal volunteers. Both HBD-1 and HBD-2 were found in BAL fluid in concentrations of several ng/ml, and both recombinant peptides showed salt-sensitive bactericidal activity. These data suggest that in the lung HBD-2 expression is induced by inflammation, whereas HBD-1 may serve as a defense in the absence of inflammation.     

Production of endothelin-1 by cultured human synoviocytes

Langerhans-cell histiocytosis (LCH) is a rare condition with a wide clinical spectrum and variable prognosis. Patients with multisystem LCH have been treated with a variety of agents but may develop resistant and progressive disease. Based on a preliminary encouraging report on the activity of 2 chlorodoxyadenosine in this disease, we administered this agent to a patient with LCH which was resistant to corticosteroids and etoposide. After 4 courses of treatment the patient achieved a complete remission which is currently ongoing for 12 months. 2 CdA appears to be effective in patients with resistant LCH and warrants investigation in previously untreated patients with poor risk disease.     

Lambdamycin, an antibiotic from Streptomyces glaucoachromogenes Prauser strain MET 31118

Lambdamycin-producing strains were detected by means of the BIP test method. The isolation technique and the physicochemical and biological properties of lambdamycin, an antibiotic produced by Streptomyces glaucoachromogenes, are described. Lambdamycin is a yellow-green pigment of the chromoglycoside type. Digitalose and fucose are the sugar components. The physicochemical properties of lambdamycin resemble those of chartreusin. However, the known biological activity is different. The antibiotic can be isolated from culture filtrates and from the mycelium by extraction with lower aliphatic alcohols. It can be purified by gel filtration methods. Lambdamycin displays antimicrobial activity, particularly against grampositive bacteria. Strains which produce enzymes inactivating different commercial antibiotics are also inhibited. Moreover, lambdamycin shows antiviral activity, as well as cancerostatic and ergotropic action in vitro and in vivo. The acute LD50 of lambdamycin in mice after 21 days was greater than 125 mg/kg when administered intraperitoneally.     

Blockade of the human cardiac K+ channel Kv1.5 by the antibiotic erythromycin

The Internet, as a global computer network, provides opportunities to make available multimedia educational materials, such as teaching files and image databases, that can be accessed using "World-Wide Web" client browser to provide continuing medical education. Since August, 1995, at the Institute of Radiology-University of Palermo, we developed a World-Wide Web server on the Internet to provide a collection of interactive radiology educational resources such as teaching files and image database for continuing medical education in radiology. Our server is based on a UNIX workstation connected to the Internet via our campus Ethernet network and reachable at the uniform resource locator (URL) address: http:/(/)mbox.unipa.it/approximately radpa/ radpa.html. Digital CT and MR images for teaching files and image database are downloaded through an Ethernet local area network from a GE Advantage Windows workstation. US images will be acquired on-line through a video digitizing board. Radiographs will be digitized by means of a Charge Coupled Device (CCD) scanner. To set up teaching files, image database and all other documents, we use the standard "HyperText Markup Language" (HTML) to edit the documents, and the Graphics Interchange Format (GIF) or Joint Photographic Expert Group (JPEG) format to store the images. Nine teaching files are presently available on the server, together with 49 images in the database, a list of international radiological servers, a section devoted to the museum of radiology hosted by our Institute, the electronic version of the Journal Eido Electa. In the first 12 months of public access through the Internet, 12,280 users accessed the server worldwide: 45% of them to retrieve teaching files; 35% to retrieve images from the database; the remaining 20% to retrieve other documents. Placing teaching files and image database on a World-Wide Web server makes these cases more available to residents and radiologists to provide continuing medical education in radiology.     

Amebicide activity of antiseptics and an antibiotic on 2 Acanthamoeba isolated from corneal ulcers

PURPOSE: To study the in vitro amoebicidal activity of antiseptics and antibiotics. METHODS: Antiseptics (hexamidine, chlorhexidine, picloxydine, PHMB, polyvidone iodine) and an antibiotic (colimycine) were tested on two Acanthamoeba isolates from corneal ulcers under soft contact lenses. The appearence of trophozo?ts and the increase of the number of cysts show their viability. RESULTS: Four antiseptics and colimycin proved to be active in vitro on the two Acanthamoeba isolates: hexamidin 0.1% after 3 to 6 hours incubation, picloxydin 0.05% after 1 to 3 hours incubation (Wilcoxon test, p < 0.05), chlorhexidin 0.02% after 3 hours (Wilcoxon test, p < 0.01), PHBM 0.02% after 3 hours (Wilcoxon test, p < 0.01) and colimycin 125,000 Ul/ml after 1 to 3 hours incubation. Polyvidone iodine proved ineffective. CONCLUSION: Our results confirm that hexamidin, chlorhexidin and PHMB have an amoebicidal activity on the two stains, and show that colimycine, which has already been tested, has also an amoebicidal activity; picloxydine is effective after 1 to 3 hours; there is a considerable variability which exists between the isolates and the sensitivity of the isolates is time-dependent. Medical polytherapy is therefore necessary especially if the sensitivity of the Acanthamoeba has not been tested.     

Sorbistin, a new aminoglycoside antibiotic complex of bacterial origin. II. Isolation and taxonomy of sorbistin-producing organism

The sorbistin-producing organism Pseudomonas sorbicinii nov. sp. has been isolated from a soil sample by psychrophilic pre-incubation technique. The organism resembles P. fluorescens in many respects but differs in some of the important physiological characteristics such as oxidase production, media specificity for the production of fluorescent pigment, and carbohydrate utilization pattern. The type strain No. D946-B83, has been deposited under the numbers ATCC 31086 and FERM-P 3328.     

Production of an Aluminium-Rich Magnesium Silicide Alloy from Atomized Powder

Abstract

Two material models are developed to estimate the effect of density on the static and cyclic fracture behaviour of a sintered steel. The models are based on the known micromechanisms of failure for each type of loading. Theoretical predictions are compared with previous experimental results taken from a companion paper (preceding). The two models successfully account for the variation of yield stress, ultimate tensile stress, and fracture toughness with density. They prove less successful in predicting the effect of density on fatigue crack propagation behaviour. PM/0198     

抗生素菌渣水热催化产油及其特性

探究了菌渣的水热液化转换成生物油燃料的过程。结果表明,抗生素菌渣在260 ℃、保留时间是135 min时,获得最大的生物油产率（28.01%）。通过6种不同的催化剂进行催化,加入催化剂后,生物油产率最大的是Na₂CO₃（36.06%）和NaOH（36.31%）。碱催化的生物油的含氮化合物的质量分数在41.16%～49.74%之间,而酸催化产生的生物油含氮化合物的量在57.62%～59.32%之间。通过调节催化剂Na₂CO₃、NaOH的添加量发现,在投加量为8%时,生物油含氮量均最低,Na₂CO₃和NaOH催化产生的生物油组分的含氮化合物质量分数分别为29.12%和35.67%。在催化剂投加量为10%时,对氧的脱除效果都最好,分别为32.12%和29.02%,此时产生的生物油的热值达到最大（达到33.3220和34.7320 MJ?kg?1）。      

Characterization of Toxoplasma gondii from the feces of naturally infected cats

Feces of 1,000 cats from a humane shelter in Columbus, Ohio, were examined microscopically for oocysts of Toxoplasma gondii and by inoculation into mice. From the first 541 cats examined, oocysts of Toxoplasma were found in the feces of seven cats but in none of the remaining 459 cats. Results of the dye test in these seven cats showed titers of antibody of less than 1:2 in four cats, and of 1:8, 1:6, and 1:32 in the remaining three cats. The pathogenicity and infectivity of oocysts and cysts of all seven strains were compared in mice after oral and intraperitoneal inoculations. Oocysts and cysts were more pathogenic when administered by the oral route than by the intraperitoneal route. The cysts were less pathogenic than the oocysts. Excellent cross-immunity between six of these seven feline strains and the M-7741 strain was deomonstrated in cats by the fact that oocysts were not shed in feces of cats challenged with cysts of homologous or heterologous strains.