Acid-fast bacteria as causative agents of skin and soft tissue infections: case presentations and literature review

Acid-fast bacteria can be implicated in skin and soft tissue infections. Diagnostic identification can be challenging or not feasible by routine laboratory techniques, especially if there is no access to the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technology. Here, we present two cases of skin and soft tissue infections caused by two different acid-fast bacteria, Nocardia brasiliensis and Mycobacterium marinum. They both grew on Löwenstein–Jensen medium, Sabouraud agar medium and blood agar medium. Both bacteria appeared acid-fast by Ziehl–Neelsen stain and Gram-positive by Gram stain. The identification was performed by MALDI-TOF MS and gene analysis. N. brasiliensis and nontuberculous mycobacterium M. marinum represent rare pathogens that cause severe skin and soft tissue infections. Failure to identify the causative agent and subsequent inappropriate or inadequate treatment may lead to severe complications or even disseminated disease, especially in immunocompromised individuals

The Acute Environment, Rather than T Cell Subset Pre-Commitment, Regulates Expression of the Human T Cell Cytokine Amphiregulin

Cytokine expression patterns of T cells can be regulated by pre-commitment to stable effector phenotypes, further modification of moderately stable phenotypes, and quantitative changes in cytokine production in response to acute signals. We showed previously that the epidermal growth factor family member Amphiregulin is expressed by T cell receptor-activated mouse CD4 T cells, particularly Th2 cells, and helps eliminate helminth infection. Here we report a detailed analysis of the regulation of Amphiregulin expression by human T cell subsets. Signaling through the T cell receptor induced Amphiregulin expression by most or all T cell subsets in human peripheral blood, including naive and memory CD4 and CD8 T cells, Th1 and Th2 in vitro T cell lines, and subsets of memory CD4 T cells expressing several different chemokine receptors and cytokines. In these different T cell types, Amphiregulin synthesis was inhibited by an antagonist of protein kinase A, a downstream component of the cAMP signaling pathway, and enhanced by ligands that increased cAMP or directly activated protein kinase A. Prostaglandin E2 and adenosine, natural ligands that stimulate adenylyl cyclase activity, also enhanced Amphiregulin synthesis while reducing synthesis of most other cytokines. Thus, in contrast to mouse T cells, Amphiregulin synthesis by human T cells is regulated more by acute signals than pre-commitment of T cells to a particular cytokine pattern. This may be appropriate for a cytokine more involved in repair than attack functions during most inflammatory responses

Investigation of volatile components in greek wines and distillates - production of medicinal wines using plants of the genus Sideritis

One of the aims of the present thesis was the analysis of the volatile components in wines produced from greek monovarietal cultivars. XAD-4 resin was finally selected for the extraction of volatiles after preliminary experimentation with several other techniques. The separation and identification of the compounds was carried out with Gas Chromatography-Mass Spectroscopy (GC/MS). Differentiation of the red wines, originating from the same geographical region, was attempted based on their flavour profile as well as discrimination of red varieties cultivated in different areas. The same procedure was applied for white wines. In addition to the wines, the volatile composition of greek distillates (tsipouro) from a Muscat-type variety (Hamburg) was also studied. Another research field of the present thesis was the phytochemical investigation of two endemic plants, namely Sideritis euboea and Sideritis clandestina subsp. clandestina, widely known in Greece as mountain tea. These plants are not thoroughly studied, even though they have been used traditionally for the treatment of the flu. Nine (9) chemical compounds were isolated and identified from the hydro-alcoholic extract of S. euboea, two of which, have never been found before in the genus. Similarly, seven (13) chemical compounds were isolated and identified from the dichloromethane and methanolic extract of S. clandestina subsp. clandestina two of which, have never been reported previously as constituents of the genus. In the last part of the thesis an effort was made to produce medicinal wines, according to an old remedy of Dioskorides, by combining Sideritis extract with greek sweet wines separately. Aroma profile screening of the corresponding wines revealed that several bioactive plant constituents, had been extracted in the wine matrix.Ένας από τους στόχους της διατριβής ήταν η μελέτη των πτητικών συστατικών οίνων που προέρχονται από ελληνικές ποικιλίες. Για την ανάκτηση των πτητικών αξιολογήθηκαν διάφορες μέθοδοι από τις οποίες τελικά επιλέχθηκε η εκχύλιση μέσω προσροφητικής ρητίνης XAD-4. Ο διαχωρισμός και η ταυτοποίηση διεξήχθη με την τεχνική της Αέριας Χρωματογραφίας με Φασματομετρία Μαζών (GC-MS). Για τους ερυθρούς οίνους, που προέρχονταν από την ίδια περιοχή, έγινε καταγραφή του προφίλ των πτητικών τους και μια πρώτη προσπάθεια διαφοροποίησης τους. Επιπλέον, έγινε σύγκριση οίνων της ίδιας ποικιλίας που προέρχονται από διαφορετικές περιοχές. Ανάλογα αξιολογήθηκαν και οι λευκοί οίνοι. Εκτός από τις ελληνικές ποικιλίες οίνων μελετήθηκαν αποστάγματα, τσίπουρα, που προέρχονταν από την ποικιλία Μοσχάτο Αμβούργου. Ένα άλλο πεδίο έρευνας της παρούσας διατριβής αποτέλεσε η φυτοχημική μελέτη δύο ενδημικών φυτών, του Sideritis euboea και του Sideritis clandestina subsp. clandestina, γνωστών στην Ελλάδα ως τσάι του βουνού. Πρόκειται για δύο φυτά της ελληνικής χλωρίδας, άμεσα συνυφασμένα με την αντιμετώπιση του κοινού κρυολογήματος, τα οποία δεν έχουν μελετηθεί επαρκώς. Από το υδατοαλκοολικό εκχύλισμα του S. euboea απομονώθηκαν και ταυτοποιήθηκαν εννέα φυσικά προϊόντα, δύο από τα οποία δεν έχουν απομονωθεί ξανά από το γένος. Αντίστοιχα, από το διχλωρομεθανολικό και μεθανολικό εκχύλισμα του S. clandestina subsp. clandestina απομονώθηκαν δεκατρία φυσικά προϊόντα, δύο από τα οποία απομονώνονται για πρώτη φορά από το γένος. Στο τελευταίο κεφάλαιο της διατριβής έγινε δοκιμαστική παραγωγή βιολειτουργικών οίνων, βασισμένων σε μια αρχαία συνταγή από τον Διοσκορίδη, συνδυάζοντας φυτά του γένους Sideritis με ελληνικούς γλυκούς οίνους. Η καταγραφή τέλος του αρωματικού προφίλ των βιολειτουργικών οίνων έδειξε ότι σημαντικά βιοενεργά μόρια εκχυλίζονται από τα φυτά στους οίνους

Epidemiological markers of pseudomonas aeruginosa

A total of 70 P. aeruginosa strains were isolated during a one year period at the University Hospital of Patras Medical School and typed by various methods. Antimicrobial susceptibility testing distinguished between susceptible and multi-resistant strains revealing a high level (18,5%) of resistance. Serotyping by International Antigenic Typing system (IATS) antisera was succesfull. A specific Ο serotype was detected in all tested strains. Non typable or polyagluttinating strains were not observed. The predominant serotype was 0:12 followed by 0:6, 0:3, 0:11 and 0:7. The majority of multiresistant strains belonged to 0:12 serotype. Strains of identical serotype were not further differentiated by lipopolysaccharide and whole cell protein electrophoretic profile. Plasmid profiles coupled with restriction endonuclease analysis revealed a common pattern in all tested strains. A common plasmid of 23kb size was present in all isolates examined, propably being a cryptic plasmid. Our results suggest that all typing systems for P. aeruginosa have merits and limitations and serotyping by IATS antisera remain the most reproducible and simple method. The combination of serotyping and a molecular biology method is the most succesfull typing system.Στο Πανεπιστημιακό Μικροβιολογικό Εργαστήριο του Γενικού Νοσοκομείου Πατρών απομονώθηκαν στη διάρκεια ενός έτους 70 στελέχη P. aeruginosa τα οποία τυποποιήθηκαν με καθιερωμένες και μη μεθόδους. Το αντιβιόγραμμα διεχώρισε αδρά σε ευαίσθητα και πολυανθεκτικά στελέχη αποκαλύπτοντας υψηλό ποσοστό πολυανθεκτικών στελεχών (18,5%). Η χρήση αντιορών του συστήματος IATS κατέταξε όλα τα στελέχη σε συγκεκριμένο ορότυπο χωρίς να παρατηρηθούν πολυσυγκολλώμενα ή μη τυποποιούμενα στελέχη. Τα πολυανθεκτικά στελέχη ανήκαν κατά πλειοψηφία στον ορότυπο 12. Επικρατούντες ορότυποι στο σύνολο των στελεχών ήσαν κατά σειρά συχνότητος 12, 6, 3, 11 και 7. Η ηλεκτροφόρηση λιποπολυσακχαριτών και ολικών πρωτεϊνών με αποδιατακτικούς παράγοντες (SDS-PAGE) δεν συνέβαλε στην ομαδοποίηση στελεχών του ιδίου οροτύπου λόγω ποικιλίας και πολυπλοκότητας της ηλεκτροφορητικής εικόνας. Η ηλεκτροφόρηση πλασμιδίων πριν και μετά την επίδραση με EcoR1, έδειξε κοινή ηλεκτροφορητική εικόνα σε όλα τα στελέχη, ένα πλασμίδιο 23kb που μεταφέρει πιθανότατα χαρακτήρα μη εκφραζόμενο στο φαινότυπο. Η χρήση αντιορών του συστήματος IATS παραμένει η απλούστερη, αποδοτικότερη και πλέον αναπαραγώγιμη μέθοδος τυποποιήσεως της P. aeruginosa, σε συνδυασμό με μεθόδους μοριακής βιολογίας

Effect of a Teucrium polium L. extract on the growth and fatty acid composition of Saccharomyces cerevisiae and Yarrowia lipolytica

Aqueous Teucrium polium extract slightly inhibits the growth of Saccharomyces cerevisiae (K-i=0.029 [g/l](-1)) and Yarrovia lipolytica (K-i=0.061 [g/l](-l)). However, this extract causes important changes in the unsaturation degree (Delta/mol) of the cellular lipids. It moreover favours the increase of the linolenic acid concentration and the decrease of the oleic one in both species

Pseudomonas aeruginosa Slime Glycolipoprotein Is a Potent Stimulant of Tumor Necrosis Factor Alpha Gene Expression and Activation of Transcription Activators Nuclear Factor κB and Activator Protein 1 in Human Monocytes

Pseudomonas aeruginosa, an opportunistic pathogen, causes infections associated with a high incidence of morbidity and mortality in immunocompromised hosts. Production of tumor necrosis factor alpha (TNF-α), primarily by cells of monocytic lineage, is a crucial event in the course of these infections. During in vivo infections with P. aeruginosa, both lipopolysaccharide (LPS) and extracellular slime glycolipoprotein (GLP) produced by mucoid and nonmucoid strains are released. In the present study, we sought to explore the relative contributions of these two bacterial products to TNF-α production by human monocytes. To this end, fresh human monocytes and THP-1 human monocytic cells were stimulated with P. aeruginosa LPS or GLP. GLP was found to be a more potent stimulus for TNF-α production (threefold higher) by human monocytes than LPS. Moreover, its effect was comparable to that of viable bacteria. Quantitative mRNA analysis revealed predominantly transcriptional regulation. Electrophoretic mobility shift assays and transfection assays demonstrated activation of NF-κB and activator protein 1 (AP-1). NF-κB activation by GLP was rapid and followed the same time course as that by viable bacteria, suggesting that bacteria could directly activate NF-κB through GLP. Moreover P. aeruginosa GLP induced the formation of AP-1 complex with delayed kinetics compared with NF-κB but much more efficiently than the homologous LPS. These results identify GLP as the most important stimulant for TNF-α production by human monocytes. Activation of NF-κB and AP-1 by P. aeruginosa GLP may be involved not only in TNF-α induction but also in many of the inflammatory responses triggered in the course of infection with P. aeruginosa

Immunohistochemical analysis of cellular infiltrate and gamma interferon, interleukin-12, and inducible nitric oxide synthase expression in leprosy type 1 (reversal) reactions before and during prednisolone treatment.

The effects of prednisolone treatment on the cellularity and cytokine (gamma interferon, interleukin-12, and inducible nitric oxide synthase) profiles of leprosy skin type 1 (reversal) reactions were studied using immunohistochemistry. Skin biopsies were taken from 15 patients with leprosy type 1 (reversal) reactions at days 0, 7, 28, and 180 after the start of steroid treatment. Prednisolone treatment had little effect at day 7, but by day 28 significant decreases were found in cytokine levels. Some patients maintained cytokine production at days 28 and 180. These results illustrate the strong Th1 profile of type 1 reactional lesions, the slow response to steroid therapy, and continuing activity at 180 days