Antimicrobial and cytotoxic activity of silver nanoparticles synthesized from two haloalkaliphilic actinobacterial strains alone and in combination with antibiotics.

AIMS: Presently, the effective antimicrobial agents have been limited by the emergence of microbial strains with multidrug resistance and biofilm formation potential. In the present study, we report remarkable antimicrobial activity of silver nanoparticles (AgNPs) synthesized from Streptomyces calidiresistens IF11 and IF17 strains, including inhibition of biofilm formation and synergistic effect of AgNPs and antibiotics against selected bacteria and yeasts. Cytotoxic effect of AgNPs on mammalian cell lines was also evaluated. METHODS AND RESULTS: Analysis of biosynthesized AgNPs by Fourier Transform Infrared Spectroscopy and transmission electron microscopy revealed their spherical shape, small size in the range of 5-50 and 5-20 nm, respectively, as well as the presence of capping agents. Study of antimicrobial activity of AgNPs against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Candida albicans and Malassezia furfur evaluated by minimum inhibitory concentration (MIC) and minimum biocidal concentration (MBC) assays revealed that MICs of AgNPs from IF11 and IF17 strains against bacteria and yeasts were found to be in the range of 16-128 and 8-256 µg ml-1 , while MBCs were in the range of 48-192 and 32-256 µg ml-1 respectively. AgNPs inhibited biofilm formation of microbial strains, which was tested by using crystal violet stain. The highest synergistic effect determined by fractional inhibitory index of AgNPs with antibiotic (kanamycin or tetracycline) was found against Staph. aureus; while in case of yeasts, M. furfur showed highest sensitivity to AgNPs-ketoconazole combination (FIC = 0·12). The cytotoxic activity of AgNPs towards HeLa and 3T3 cell lines was studied by MTT assay. The IC50 of AgNPs estimated against mouse fibroblasts was found to be 8·3 and 28·3 µg ml-1 and, against HeLa cell line, 28·5 and 53·8 µg ml-1 respectively. CONCLUSIONS: It can be concluded that AgNPs synthesized from S. calidiresistens IF11 and IF17 strains have potential as an effective antimicrobial and cytotoxic agent, especially when used in combination with antibiotics/antifungal agents. SIGNIFICANCE AND IMPACT OF THE STUDY: This study indicates potential application of biogenic silver nanoparticles as an antimicrobial agent in nanomedicine.

Evaluation of cytotoxicity, immune compatibility and antibacterial activity of biogenic silver nanoparticles.

The study was focused on assessment of antibacterial activity, cytotoxicity and immune compatibility of biogenic silver nanoparticles (AgNPs) synthesized from Streptomyces sp. NH28 strain. Nanoparticles were biosynthesized and characterized by UV-Vis spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, nanoparticle tracking analysis system and zeta potential. Antibacterial activity was tested against Gram-positive and Gram-negative bacteria; minimal inhibitory concentration was recorded. Cytotoxicity was estimated using L929 mouse fibroblasts via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Biocompatibility of AgNPs was performed using THP1-XBlue™ cells. Biogenic AgNPs presented high antibacterial activity against all tested bacteria. Minimum inhibitory concentration of AgNPs against bacterial cells was found to be in range of 1.25-10 µg/mL. Silver nanoparticles did not show any harmful interaction to mouse fibroblast cell line, and no activation of nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) cells was observed at concentration below 10 µg/mL. The half-maximal inhibitory concentration (IC50) value was established at 64.5 µg/mL. Biological synthesis of silver can be used as an effective system for formation of metal nanoparticles. Biosynthesized AgNPs can be used as an antibacterial agent, which can be safe for eukaryotic cells.

[Karyometry of BBN-induced precancerosis of the urothelium : An experimental analysis]. / Karyometrie BBN-induzierter Präkanzerosen des Urothels : Eine experimentelle Analyse.

BACKGROUND: The morphology of experimental precancerous lesions of the urinary bladder has been interpreted quite differently by various authors. OBJECTIVES: The aim of this investigation was to quantify these lesions by karyometry and, thus, to gain a more reliable understanding of the process. MATERIALS AND METHODS: A total of 60 Wistar rats were fed with N­butyl-N-(4-hydroxybutyl)nitrosamine (BBN) at a concentration of 0.05 % in their drinking water to induce preneoplastic changes of the urothelium. After the second week of BBN exposition, 6 animals were killed every 2 weeks up to week 20. Smears of the scraped off urothelium of 3 urinary bladders of each group were analyzed cytologically and karyometrically. RESULTS: BBN exposition led to statistically significant changes of the karyometric values using the χ2 test to differentiate the control animals from the ones that had ingested BBN and the 2­week groups from each other. These changes consisted mainly in significant deviations of the size of the nuclear area within the different groups. CONCLUSION: Morphological and karyometrical analysis showed that biologically relevant stages in the development of chemically induced urothelial precancerous lesions could be realized much earlier than had been assumed in recent publications. Karyometric analysis offered a valid basis to describe the early morphologic alterations of carcinogenesis.

Study of silver nanoparticles synthesized by acidophilic strain of Actinobacteria isolated from the of Picea sitchensis forest soil.

AIMS: In the present work the acidophilic actinobacteria strain was used as a novel reducing agent for the cheap, green and single-step synthesis of nanostructure silver particles. Structural, morphological and optical properties of the synthesized nanoparticles have been characterized by spectroscopy, dynamic light scattering and electron microscopy approach. The antimicrobial activity of silver nanoparticles against clinical strains such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis and Salmonella infantis alone and in combination with antibiotics were studied. METHODS AND RESULTS: The crystalline and stable biosynthesized silver nanoparticles ranged in size from 4 to 45 nm and were mostly spherical in shape being characterized evolving several analytical techniques. The bioAgNPs inhibited growth of most bacterial strains. The highest antimicrobial activity was observed against Ps. aeruginosa (10 mm), followed by Staph. aureus, B. subtilis and Pr. mirabilis (all 8 mm). The lower activity was noticed for E. coli and Kl. pneumoniae (6 and 2 mm, respectively). Moreover, the synergistic effect of bio(AgNPs) with various commercially available antibiotics was also evaluated. The most significant results were observed for bio(AgNPs) combined with tetracycline, kanamycin, ampicillin and neomycin, followed by streptomycin and gentamycin against E. coli, Salm. infantis and Kl. pneumoniae. The most resistant bacteria to commercial antibiotics was Pr. mirabilis. CONCLUSION: The Streptacidiphilus sp. strain CGG11n isolated from acidic soil can be used to efficiently synthesize the bioactive nanoparticles using inexpensive substances in an eco-friendly and nontoxic manner. The present work provides helpful insight into the development of new antimicrobial agents with the synergistic enhancement of the antibacterial mechanism against pathogenic micro-organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: The synthesized silver bionanoparticles from Streptacidiphilus sp. strain CGG11n possess potent inhibitory effect that offers valuable contribution to pharmaceutical associations.

Acidophilic actinobacteria synthesised silver nanoparticles showed remarkable activity against fungi-causing superficial mycoses in humans.

Superficial mycoses are limited to the most external part of the skin and hair and caused by Malassezia sp., Trichophyton sp. and Candida sp. We report extracellular biosynthesis of silver nanoparticles (AgNPs) by acidophilic actinobacteria (SF23, C9) and its in vitro antifungal activity against fungi-causing superficial mycoses. The phylogenetic analysis based on the 16S rRNA gene sequence of strains SF23 and C9 showed that they are most closely related to Pilimelia columellifera subsp. pallida GU269552(T). The detection of AgNPs was confirmed by visual observation of colour changes from colourless to brown, and UV-vis spectrophotometer analysis, which showed peaks at 432 and 427 nm, respectively. These AgNPs were further characterised by nanoparticle tracking analysis (NTA), Zeta potential, Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The FTIR analysis exhibited the presence of proteins as capping agents. The TEM analysis revealed the formation of spherical and polydispersed nanoparticles in the size range of 4-36 nm and 8-60 nm, respectively. The biosynthesised AgNPs were screened against fungi-causing superficial mycoses viz., Malassezia furfur, Trichophyton rubrum, Candida albicans and C. tropicalis. The highest antifungal activity of AgNPs from SF23 and C9 against T. rubrum and the least against M. furfur and C. albicans was observed as compared to other tested fungi. The biosynthesised AgNPs were found to be potential anti-antifungal agent against fungi-causing superficial mycoses.

Schistosoma japonicum infection and rectal carcinoid tumour: underreported coincidence or neglected association?

Schistosoma japonicum infection associated with a rectal carcinoid in an asymptomatic 44-year-old female from the Philippines is described. A systematic review of the literature could not identify similar reports, suggesting a rare coincidence. However, epidemiological data on the frequency of both conditions as well as published results of a colorectal screening programme from China indicate that underreporting of this concurrence is likely. Moreover, several studies suggest a causal link between schistosomiasis caused by S. japonicum and more common gastrointestinal malignancies such as colorectal carcinoma. Hence the presented case and the apparent neglect of this observation in the current literature allow speculation on a role of S. japonicum in the pathogenesis of rare gastrointestinal neoplasms such as carcinoid tumours as well. Future reports on similar observations could help to determine the need for systematic investigations and are strongly encouraged.

Rapid identification of Helicobacter pylori by capillary electrophoresis: an overview.

Helicobacter pylori can cause gastritis and peptic ulcers and is directly associated with the development of gastric cancer. There are many types of diagnostic methods used to identification H. pylori (invasive and non-invasive), but these methods usually require time-consuming and laborious procedures and therefore are not capable of fast diagnosis in cases of emergency. This contribution describes the new achievements, interdisciplinary significance and some future directions in the application of capillary electrophoresis for determination of H. pylori.

[Phenprocoumon-induced liver failure]. / Phenprocoumon-induziertes Leberversagen.

HISTORY: A 61-year-old woman was referred because of painless jaundice, laboratory tests having indicated hepatitis with impaired liver functions. For the past two years she had been taking phenprocoumon because she had atrial fibrillation. INVESTIGATIONS: Serological tests largely excluded infectious, autoimmune or metabolic etiology, so that the diagnosis of drug-induced hepatic disease was made. Liver biopsy showed necrotic liver cells and mild inflammatory reaction. TREATMENT AND COURSE: A perforating duodenal ulcer required urgent surgical intervention, after which liver functions further deteriorated. The patient having refused liver transplantation she was treated symptomatically (oral vitamin K. lactulose, diuretics), phenprocoumon was discontinued and her condition slowly improved. She was discharged after two months. At subsequent examination she was symptom-free, the INR was 1.41, transaminases were normal and ultrasound merely showed a slightly inhomogeneous internal structure. CONCLUSION: Phenprocoumon can cause liver damage even when the drug has been taken for prolonged periods without any problems. A careful history about previously administered drugs should be taken in any case of hepatitis of uncertain etiology.

Application of the Weibull distribution to describe the vertical distribution of cesium-137 on a slope under permanent pasture in Luxembourg.

The application of solutions of the Advection-Dispersion-Equation (ADE) for soil profiles is sometimes questionable. An alternative method, based on the Weibull distribution, has been developed, which can approximate the vertical distribution of radiocesium (137Cs) and allows extrapolation to account for the complete inventory. The structure of the equation allows simple parameters describing the soil depth profile to be derived. Reliable estimates of the total 137Cs inventory can help to explain the lateral distribution. This equation was used to analyse the 137Cs-activities of Chernobyl fall-out measured on a slope under permanent pasture in Luxembourg.

[Severe cholestasis with kidney failure from anabolic steroids in a body builder]. / Schwere Cholestase mit Nierenversagen durch Anabolika bei einem Bodybuilder.

HISTORY AND ADMISSION FINDINGS: A 28-year-old body builder was admitted because of jaundice. For 80 days, until 3 weeks before hospitalization, he had been taking moderately high doses of anabolic steroids: metandienone (methandienone), 10-50 mg daily by mouth, and stanozolol, 50 mg intramuscularly every other day. Physical examination was unremarkable except for yellow discoloration of the skin and sclerae. INVESTIGATIONS: Bilirubin concentration was raised to 4.5 mg/dl, cholestasis enzymes were normal, while transaminase activities were raised. Liver biopsy was compatible with cholestasis induced by anabolic steroids. TREATMENT AND COURSE: Although the steroids had been discontinued, the patient's general condition deteriorated over 7 weeks. Serum bilirubin rose up to a maximum of 77.9 mg/dl. In addition renal failure developed with a creatinine concentration of 4.2 mg/dl. The patient's state improved simultaneously with the administration of ursodeoxycholic acid and the biochemical values gradually reached normal levels after several weeks. CONCLUSION: Anabolic steroids can cause severe cholestasis and acute renal failure. In this case there was a notable temporal coincidence between the administration of ursodeoxycholic acid and the marked clinical improvement.

Oral budesonide and ursodeoxycholic acid for treatment of primary biliary cirrhosis: results of a prospective double-blind trial.

BACKGROUND & AIMS: Ursodeoxycholic acid (UDCA) is used for treatment of primary biliary cirrhosis. Previous studies showed that, compared with UDCA monotherapy, bile salts plus prednisolone had no further effect on laboratory data but improved liver histology. Thirty percent of these patients had prednisolone-related side effects. Budesonide is a glucocorticoid with a high receptor affinity and a high first-pass metabolism. In this study we investigated whether budesonide and UDCA are superior to UDCA monotherapy. METHODS: A 2-year prospective, controlled double-blind trial was performed. Twenty patients (mainly with early-stage disease) were treated with UDCA at a dose of 10-15 mg/kg daily in addition to 3 mg budesonide 3 times daily (group A), and 19 patients (1 dropped out for personal reasons) were treated with UDCA plus placebo (group B). Liver biopsy specimens were taken before, after 12 months, and at the end of study. Glucose tolerance tests, serum cortisol levels, and adrenocorticotropin-stimulated cortisol secretion were assessed at regular intervals. Bone mass density was measured by dual-energy photon absorptiometry. RESULTS: Compared with pretreatment values, liver enzyme and immunoglobulin M and G levels decreased significantly in both groups. Improvement in group A was significantly more pronounced (P < 0.05) than in group B. Titers of antimitochondrial antibodies did not change. In group A, the point score of liver histology improved by 30.3%; in group B, it deteriorated by 3.5% (P < 0.001). Changes in bone mineral density after 2 years were -1.747% in group A and -0.983% in group B (P = 0.43). Budesonide had little influence on the hypothalamic-pituitary-adrenal axis. One patient in group A had budesonide-related side effects; in 3 patients in group B, complications of liver disease developed. CONCLUSIONS: Combination therapy with UDCA and budesonide is superior to UDCA and placebo.

[Miliary pneumonia after the intravesical BCG therapy of a superficial urothelial carcinoma of the bladder]. / Miliare Pneumonie nach intravesikaler BCG-Therapie eines oberflächlichen Urothelkarzinoms der Harnblase.

HISTORY AND ADMISSION FINDINGS: A multilocular superficial epithelial carcinoma (T1G3) and carcinoma in situ (Cis G3) of the bladder were resected transurethrally followed by intravesical instillation of BCG. The initial cycle of BCG administration had been free of complication, but then high fever, fatigue, cough and dyspnoea had developed with subsequent BCG maintenance treatment. Physical examination on admission revealed fever, clearly reduced general condition, and increased breath sounds with fine rales in the upper and middle lobes. INVESTIGATIONS: A clearly raised erythrocyte sedimentation rate (86 mm/h) and a CRP level at the upper limit of normal (13.6 mg/dl) indicated marked inflammatory reaction. The chest radiogram showed diffuse miliary opacities. Mycobacteria were not demonstrated in either gastric juice or bronchial secretion. TREATMENT AND COURSE: As BCG-induced miliary pneumonia was diagnosed, triple tuberculostatic treatment was commenced (ethambutol, 1200 mg/d; rifampicin, 600 mg/d; isoniazid, 300 mg/d). Nonetheless his condition deteriorated further. When prednisolone, 40 mg/d was added the symptoms improved rapidly. The tuberculostatic drugs were continued for 6 months. All symptoms had disappeared after 4 months. CONCLUSION: Miliary pneumonia is a rare complication of intravesical BCG installation of a superficial bladder cancer. As living bacteria cannot be excluded as the cause, triple tuberculostatic treatment must be started at once. If this fails to bring about improvement, additional steroid medication is recommended.

[Necrotizing hepatitis after taking herbal remedies]. / Nekrotisierende Hepatitis nach Einnahme pflanzlicher Heilmittel.

HISTORY AND CLINICAL FINDINGS: Two unrelated women, aged 39 and 42 years, had been admitted (at different times) to hospital because of "recurrence of an aetiologically uncertain acute hepatitis". Both patients had a history of acute hepatitis with GPT concentration of 796 and 755 U/l, respectively. Each of them had experienced recurrences of hepatitis, each of them preceded by taking herbal remedies as alternative medication, containing kava or common (or lesser) celandine, respectively. In each patient physical examination had been unremarkable. INVESTIGATIONS: Maximal values of GPT in the two patients were 422 and 350 U/l, respectively. Viral, autoimmune and metabolic causes of the hepatitis were excluded. In each of them liver biopsy revealed the picture of acute necrotizing hepatitis. DIAGNOSIS, TREATMENT AND COURSE: As it was suspected that the hepatitis was medication-induced, the intake of the mentioned herbal preparations was stopped. The liver function tests quickly became normal. CONCLUSION: In view of the rapid response to their withdrawal, a causal connection between intake of the herbal preparations and the recurrences of acute hepatitis is the most likely explanation in both cases.

Production of B-group vitamins by Azospirillum spp. grown in media of different pH at different temperatures.

Studies were carried out on B-group vitamin (thiamine, biotin, nicotinic acid, riboflavin, pantothenic acid) production by 3 strains of Azospirillum (one derived from coniferous ectomycorrhizae and two--from sporocarps of ectomycorrhizal fungi) grown in media of different pH (5.5, 6.5, 7.5) at different temperatures (10 degrees C, 20 degrees C, 26 degrees C). Riboflavin was produced in largest amounts by all the strains studied; biotin was not detected in culture filtrates at all. Qualitative-quantitative composition of vitamins in post culture liquids of azospirilla depended on the temperature of growth, pH of the medium and on the strain studied. Thiamine was synthesized in largest quantities at pH 5.5 by all strains of Azospirillum--independently of the temperature of growth. In media of higher pH this vitamin was detected in considerably smaller amounts or was not detected at all. The smallest quantities--and the smallest numbers of vitamins produced were observed at temperature 10 degrees C and pH 5.5.

Melanocytic neuroendocrine carcinoma of the thymus.

A neuroendocrine carcinoma of the thymus with an ectopic adrenocorticotropic hormone (ACTH) syndrome and melanocytic differentiation is described. ACTH, neuron-specific enolase (NSE) and S-100 protein were identified in the tumor by immunocytochemistry. Neurosecretory granules and melanosomes could be demonstrated in different cell populations by electronmicroscopy. The clinicopathologic findings are presented. The literature is briefly discussed.

[Intestinal lipodystrophy (M. Whipple). Synopsis of radiology, endoscopy and histology]. / Intestinale Lipodystrophie (M. Whipple). Synopsis von Radiologie, Endoskopie und Histologie.

The case of a 48 years old man with intestinal lipodystrophy (Whipple's disease) is clinically, roentgenologically, endoscopically and histologically documented. The diagnosis was established by endoscopic biopsy and laparatomy. The patho-histologic changes of the mucosa of the proximal small bowel are pathognomonic. Roentgenologically the characteristic mucosal and lymphadenoid changes can be demonstrated as well as the extent of the process.

Generic composition and physiological and cultural properties of heterotrophic bacteria isolated from soil, rhizosphere and mycorrhizosphere of pine (Pinus silvestris L.).

Among the bacteria studied Arthrobacter globiformis was predominating in the root zone, while in the non-rhizosphere soil most numerous were Bacillus circulans and A. globiformis. Ammonifiers were more numerous among the root zone bacteria than among the root free soil organisms. The reverse was noted with bacteria capable of hydrolysing starch, cellulose, pectin and chitin.

Metabolic activity of bacteria isolated from soil, rhizosphere and mycorrhizosphere of pine (Pinus silvestris L.).

Casamino acids were found to be the best substrate for bacteria isolated from soil, rhizosphere and mycorrhizosphere of pine. Most active with this substrate were however the root zone bacteria. Glucose was oxidized similarly by the bacteria isolated from the three sources.