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Marjolin ulcers are malignant neoplasia developing in chronic open wounds and pathological scars. A definitive diagnosis is made by histological examination of permanent sections. Frozen section biopsy has been widely used for intraoperative diagnosis and evaluation of surgical excision safety margins. This preliminary study aims to discuss the reliability of a simpler and faster method -- intraoperative cytology -- in the diagnosis of Marjolin ulcers.Touch or scrape smears of 76 Marjolin ulcers from 22 patients were assessed, and features were compared to the histological appearance of permanent sections.Cytology revealed squamous cell carcinoma (SCC) in 45 ulcers from 11 patients. Histology confirmed SCC in 48 ulcers from 12 patients. No false-positive and one false-negative results were found. Cytology was found to have a 98.7% accuracy, 98% sensitivity and 100% specificity in the intraoperative diagnosis of Marjolin ulcers.Cytology is a fast and reliable alternative in the intraoperative diagnosis of Marjolin ulcers.

Aim: The sites of haematopoiesis during human ontogeny can be correlated to the sites where haematopoiesis occurs in vertebrate phylogeny. As haematopoiesis has been described in the diencephalon and pituitary gland of water-inhabiting vertebrates we wanted to find out whether such a phenomenon also occurs in human embryos. Material and Methods: Paraffin-embedded specimens from the diencephalon and pituitary gland of human embryos at the 7th to 22nd gestational week and from adults were investigated by conventional histology and immunohistology for the presence of haematopoietic cells. Results: Cellular accumulations predominantly of erythroid and megakaryocytic lineage were identified in the floor of the developing diencephalon of the 7th/8th gestational week. At the older developmental stages of the 18th to 22nd gestational week loose aggregates of haematopoietic cells within the leptomeningeal spaces adjacent to the hypophyseal infundibulum were detected in 2 out of 7 cases analyzed. Conclusions: As it has been proposed that lymphohaematopoietic clusters occasionally occur within the brain in bone marrow-less vertebrates as a response to noxious agents, we speculate that this temporal appearance of haematopoietic cell clusters within the diencephalon floor in early human ontogeny could also be due to fetal immunomodulations.

Corticotropin-releasing factor agonists exert inhibitory effects in stomach functions possibly through peripheral routes. We have previously reported the expression of Urocortin (Ucn) I, an endogenous ligand of both CRF receptor types CRF(1) and CRF(2), in the human stomach. We examined CRF(1) and CRF(2) expression in the same tissue. Using RT-PCR, CRF(2) but not CRF(1) transcripts were detected in RNA extracts from normal human stomach. In addition, immunohistochemical analysis revealed receptor protein in epithelial gastric cells. In order to investigate the biological role of CRF(2) in these cells, an in vitro model was established, using the gastric cancer cell line AGS transiently transfected to express functional CRF(2). The effect of the CRF(2) endogenous ligands CRF, Ucns I and II on the growth parameters of the AGS/CRF(2) was examined. After 1 day of exposure, all three ligands reduced the degree of apoptosis (16%-19%, n = 9, P < 0.05) compared to non-treated controls and this effect was observed for 3 days of treatment. No such effect was detected in non-transfected cells, suggesting mediation through CRF(2) receptors. Administration of CRF, Ucns I and II had no effect on the proliferation rate of AGS/CRF(2) cells or on the release of PGE(2) by them. Our results demonstrate CRF(2) expression in the human gastric mucosa and indicate a physiological role of this receptor type in regulating apoptosis, an important parameter of gastric cell regeneration. Paracrine effects exerted by locally expressed endogenous ligands, such as Ucn I, support a significant role of the peripheral CRF system in gastric physiology. J. Cell. Physiol. 209: 905-911, 2006. (c) 2006 Wiley-Liss, Inc.

AIM The effectiveness and safety of ibutilide (IB) use in patients receiving amiodarone or propafenone for atrial flutter (AFL) and atrial fibrillation (AF) were compared to IB alone. METHODS AND RESULTS In 104 consecutive patients with AF (65%) or AFL (35%), receiving amiodarone (n = 46), propafenone (n = 30), or no specific antiarrhythmic drug (n = 28), IB was given for cardioversion. Fifteen patients in amiodarone group were loaded with 1.2 g intravenously before IB administration. The mean duration of arrhythmia episode was 23 +/- 65 days, while 85% of patients had structural heart disease. The left ventricle ejection fraction was 57 +/- 10% and the left atrium size was 4.2 +/- 0.6 cm. The conversion efficacy did not differ among groups (62% for amiodarone vs 55% for propafenone vs 64% for IB alone). The QTc intervals were significantly prolonged, at 10 minutes and 30 minutes after IB administration, in amiodarone group (from 449 +/- 88 to 496 +/- 92 ms, 508 +/- 52 ms; P = 0.001) and in the group where IB was used alone (from 434 +/- 45 to 517 +/- 74 ms, 492 +/- 65 ms; P < 0.001), while it remained unchanged in propafenone group (from 464 +/- 52 to 471 +/- 80 ms, 489 +/- 93 ms; P = 0.536). The only predictor of conversion was the presence of AFL (P = 0.009). Five patients developed ventricular tachycardias after IB administration (two in propafenone, one in amiodarone, and two in IB group). CONCLUSIONS The use of IB in patients receiving amiodarone or propafenone for AFL or AF is equally effective and safe as the use of IB alone. The presence of AFL is the stronger predictor factor for cardioversion.

Coexistence of B- and T-cell lymphoid malignancies has been reported sporadically.A 68-year-old woman developed a lymphoid neoplasm in the large intestine and a second lymphoid neoplasm in the esophagus, 24 months after the diagnosis of the first lymphoma. Immunophenotypic analyses were consistent with extranodal marginal zone B-cell mucosa-associated lymphoid tissue type (MALT type) and peripheral T-cell unspecified lymphomas in the large intestine and the esophagus, respectively. The molecular analysis confirmed the B-clonal genotype of the first lymphoma, and disclosed a biclonal genotype of the second one (composite T- and B-cell lymphoma). No evidence of Epstein-Barr virus (EBV) association was shown in either tumor.B- and T-cell neoplasms represent two distinct malignancies rather than progression of the same neoplastic clone.

Aim: Polymorphous low grade adenocarcinoma of the salivary glands (PLGA) is a low grade neoplasm that predominantly occurs in the minor salivary glands. In this site is amenable to biopsy and histologic diagnosis. However, experience with cytological findings in these tumors is limited. We describe the cytology of this entity. Experimental design: Touch imprint cytology of a primary parotid PLGA is specified and correlated with histology. Results: Smears were hypercellular showing branching papillae, sheets and clusters of uniform cells with bland nuclei, dispersed chromatin and no nucleoli. The cells had a scant to moderate amount of eosinophilic cytoplasm. They formed tubular structures containing hyaline globules. Conclusions. The cytologic differential diagnosis of PLGA includes adenoid cystic carcinoma, pleomorphic adenoma, and monomorphic adenoma. PLGA should be considered in the differential diagnosis of head and neck tumors, where the cytology suggests on of the above mentioned tumors, even when the clinical findings (involvement of a major salivary gland, lymph node metastasis) is not typical of PLGA.

Aim: To determine the immunoreactivity of pancreatic-polypeptide (PP) during the development of the human fetal pancreas and ductal pancreatic adenocarcinoma, given that, PP positive cells were demonstrated either into its embryonic anlage or into pancreatic cancer. Methods: Tissue sections from 15 pancreatic fetal specimens, and equal number of ductal adenocarcinoma specimens, were assessed. Results: The density of positive cells in the primitive exocrine ductal epithelium and endocrine epithelium was significantly higher than the relevant density in the neoplastic pancreatic tissue of mixed (ductal – endocrine) and pure ductal type (p1=0.001, p2

Aim: The maturation of most T- lymphocyte precursors takes place within the meshwork of thymic epithelial cells. Different steps of this process can be defined by immunologic phenotyping. The prothymocytes are positive for the terminal deoxynucleotidyl transferase (TdT) and give rise to cortical thymocytes, which express CD1, CD2, CD3, CD5, and both CD4 and CD8. These CD4 and CD8 double-positive cortical thymocytes differentiate into two lineages: CD4+ or CD8+ lymphocytes of the thymic medulla, by the tenth week of gestation. Our study points towards the determination of the CD8 cytotoxic/suppressor capacity of the fetal thymus in Down’s syndrome. Experimental design: A quantitative comparison of T-lymphocytes (CD3, CD4, and CD8) in the thymic parenchyme in embryos after voluntary abortion during 2nd trimester of gestation and embryos with Down’s syndrome, respectively, was performed. Results: Our results showed: 1) A statistically significant depletion in the total number of T-cells (CD3 positive) in the cases of embryos with Down’s syndrome over those after voluntary abortion, during the second trimester of gestation (p

Στην παρούσα μελέτη αποδείξαμε ότι τα επίπεδα του ΝΟ (όπως αυτά αντανακλώνται μέσω του προσδιορισμού του ΝΟχ) είναι αυξημένα στους ασθενείς με κίρρωση και κυρίως στους ασθενείς με ΗΕ. Το γεγονός ότι τα αυξημένα επίπεδα του ΝΟχ στην ΗΕ είναι ανεξάρτητα από τη βαρύτητα της ηπατικής νόσου μας κάνει να πιστεύουμε ότι αυτή η διέγερση της παραγωγής του ΝΟ συμμετέχει ενεργά στην παθογένεια της ΗΕ και δεν αποτελεί απλώς μία ακόμα μεταβολική διαταραχή της κίρρωσης. Σε αρκετές μελέτες έχει αναφερθεί η επαγωγή της σύνθεσης του ΝΟ στην κίρρωση από κυτταροκίνες (IL-1, IL-6, TNF-a), αντιπροσωπεύοντας μία φλεγμονώδη κατάσταση που ίσως περιλαμβάνει υποκλινικές λοιμώξεις. Σε αυτή τη μελέτη χρησιμοποιήσαμε ως αδρό δείκτη φλεγμονής τα επίπεδα CRP και αποκλείσαμε όλους τους ασθενείς με κλινικές ή απεικονιστικές ενδείξεις λοίμωξης ή καρκίνου. Τα αποτελέσματα της στατιστικής ανάλυσης επιβεβαίωσαν τη σημαντική συσχέτιση μεταξύ επιπέδων CRP, επιπέδων ΝΟχ και παρουσίας ΗΕ. Όμως, τα επίπεδα της CRP, σε αντίθεση με αυτά του ΝΟχ και της αμμωνίας, δεν αποτελούν προγνωστικό δείκτη για την παρουσία της ΗΕ. Γεγονός είναι ότι δεν είναι ξεκάθαρο αν τα επίπεδα της CRP αντανακλούν υποκλινικές λοιμώξεις ή απλά αντιπροσωπεύουν τη γενικότερη φλεγμονή της διεργασίας της ηπατικής κίρρωσης. Τέλος, θεωρήσαμε χρήσιμο να εκτιμήσουμε τη χρησιμότητα του προσδιορισμού των επιπέδων του ΝΟχ και της αμμωνίας στην κλινική πράξη. Καταλήξαμε ότι οι ανώτερες φυσιολογικές τιμές για το ΝΟχ ήταν 148μmol/L και για την αμμωνία 75μg/dl, έχοντας παρόμοια ευαισθησία και ειδικότητα. Ο συνδυασμός ΝΟχ-αμμωνίας ως ενιαίο διαγνωστικό μοντέλο οδήγησε σε σημαντική ενίσχυση της ειδικότητας, της PPV και της PLR σε σύγκριση με τη χρησιμοποίηση καθενός ξεχωριστά. Τελικά, ο προσδιορισμός των επιπέδων ΝΟχ συγχρόνως με τα επίπεδα αμμωνίας θα μπορούσε να συμβάλει στην αξιόπιστη διάγνωση της ΗΕ.Συμπεράσματα Με τη μελέτη αυτή αποδείξαμε ότι τα επίπεδα ΝΟχ και αμμωνίας είναι αυξημένα σε ασθενείς με ηπατική κίρρωση και ΗΕ. Επιπλέον, αποδείξαμε ότι τα επίπεδα του ΝΟχ σχετίζονται καλύτερα με την βαρύτητα της ΗΕ από ό,τι αυτά της αμμωνίας. Παρά το γεγονός ότι το ΝΟ και η αμμωνία αποτελούν τους βασικούς κρίκους της παθογένειας της ΗΕ, πρόσθετοι παράγοντες, όπως φλεγμονώδεις διεργασίες, ίσως να σχετίζονται με την εμφάνισή της. Τέλος, πιστεύουμε ότι ο προσδιορισμός των επιπέδων του ΝΟχ στην κλινική πράξη μπορεί να συμβάλει ουσιαστικά στη διάγνωση της ΗΕ.

Brucellosis is a zoonotic infection with a worldwide distribution, endemic in the Mediterranean region, and is associated with high morbidity in humans [1,2]. Osteoarticular complications are the most common focal complications of Brucella spp. infection [3]. These complications commonly affect the axial skeleton, with vertebral spondylitis accounting for 35%–50% of all osteoarticular complications [4–6]. Estimates of the incidence of spondylitis range from 9% to 31% [4,5]. While lumbar spine involvement is the most common, cervical involvement is a rare, but more severe, complication, accounting for 8.3% of cases of vertebral osteomyelitis in a recent study [4]. We present a case of brucellar spondylitis with paravertebral mass in the cervical segment that resulted in neurological deficits.

The adsorption of the neutral macromonomeric surfactant Tween-80 from electrolyte solutions on a polarized mercury electrode was studied by means of differential capacitance measurements of the ele...

Background Acute exercise may exert deleterious effects on the cardiovascular system through a variety of pathophysiological mechanisms, including increased platelet activation. However, the degree of exercise-induced platelet activation in untreated hypertensive (UH) individuals as compared with normotensive (NT) individuals has yet to be established. Furthermore, the effect of antihypertensive treatment on exercise-induced platelet activation in essential hypertension (EH) remains unknown. Methods Study 1 consisted of 30 UH and 15 NT subjects. UH subjects who received treatment were included in study 2 and were followed-up after a 3-month treatment period with an angiotensin II receptor blocker (ARB; valsartan). Circulating monocyte-platelet aggregates (MPA) and platelet P-selectin were measured as platelet activation markers at baseline, immediately after a treadmill exercise test, and 10, 30, and 90 minutes later. Results Maximal platelet activation was observed at 10 minutes after peak exercise in both groups. In UH subjects, MPA levels remained increased at 30 minutes after peak exercise, despite BP fall to baseline levels. MPA levels were significantly higher in UH subjects than NT subjects at maximal exercise and at 10 and 30 minutes of recovery. Post-treatment MPA levels increased significantly only at 10 minutes into recovery and were similar to those of NT subjects. Conclusions Acute high-intensity exercise exaggerates platelet activation in untreated patients with EH compared with NT individuals. Angiotensin II receptor blockade with adequate BP control greatly improves exercise-induced platelet activation in EH. Further studies are needed to clarify whether this phenomenon depends purely on BP lowering or benefits also from the pleiotropic effects of ARBs.

The electrochemical studies on a glassy carbon electrode in acetonitrile solutions of dinuclear copper(I) complexes with the general formula [Cu(tmtp)(L)Br]2, where tmtp = tri-m-tolylphosphine and L = pyridine-2-thione (pyridine-2-thione (py2SH), 1,3-thiazolidine-2-thione (tzdtH), benz-1,3-imidazoline-2-thione (bzimtH2) and quinoline-2-thione (quintH) have been carried out. The monitoring of the peak position versus scan rate combined with semi-empirical calculations on model compounds provide a suitable method for the characterization of the nature of the bridge formed between the two copper atoms, which may be either sulphur or halogen.

Background Spontaneous bacterial peritonitis (SBP) is historically caused by Gram-negative bacteria (GNB) almost exclusively Enterobacteriaceae. Recently, an increasing rate of infections with Gram-positive cocci (GPC) and multidrug-resistant (MDR) microorganisms was demonstrated. Aims To assess possible recent changes of the bacteria causing SBP in cirrhotic patients. Methods We retrospectively recorded 47 cases (66% males) during a 4-year-period (2008–2011). Results Twenty-eight (60%) patients had healthcare-associated infections while 15 (32%) received prophylactic quinolone treatment. GPC were found to be the most frequent cause (55%). The most prevalent organisms in a descending order were Streptococcus spp (n = 10), Enterococcus spp (n = 9), Escherichia coli (n = 8), Klebsiella pneumonia (n = 5), methicillin-sensitive Staphylococcus aureus (n = 4) and coagulase-negative Staphylococcus spp (n = 3). Nine of the isolated bacteria (19%) were MDR, including carbapenemase-producing K. pneumonia (n = 4), followed by extended-spectrum beta-lactamase-producing E. coli (n = 3) and Pseudomonas aeruginosa (n = 2). MDR bacteria were more frequently isolated in healthcare-associated than in community-acquired infections (100% vs 50%, P = 0.006), in patients receiving long-term quinolone prophylaxis (67% vs 24%, P = 0.013) and in those with advanced liver disease as suggested by higher MELD score (28 vs 19, P = 0.012). More infections with GNB than GPC were healthcare-associated (81% vs 42%, P = 0.007). Third-generation cephalosporin resistance was observed in 49% and quinolone resistance in 47%. Conclusions GPC were the most frequent bacteria in culture-positive SBP and a variety of drug-resistant microorganisms have emerged. As a result of high rates of resistance in currently recommended therapy and prophylaxis, the choice of optimal antibiotic therapy is vital in the individual patient.

In this work a new geophysical methodology is presented which is able to detect any displacements of buried electrodes that are permanently installed in boreholes. These displacements can seriously affect the quality of the measurements and the subsequent resistivity inversion image. The exact knowledge of the electrode displacements will either help in correcting the electrode coordinates and the geometric factors of the measurements associated with these electrodes or just to reject all corresponding erroneous measurements. During this method pole-pole type measurements are conducted, where the current is injected in every buried electrode in the borehole and the potential is measured on a number of electrodes that are spread out along a line on the ground surface. A finite-difference least-squares non-linear inversion algorithm with damping constraints has been developed in an effort to recover the accurate coordinates of the borehole electrodes. Although a priori resistivity model resulted by a surface ERT or by any other geological and geophysical information can be used to constrain the optimization algorithm it is also shown that that the lack of this knowledge does not affect the resulting electrode positioning. The validity and effectiveness of the approach was tested through synthetic modeling and real data.

The dependence of the differential capacitance (C) of the electrode double layer of a hanging mercury drop electrode in bis (2-ethylhexyl) sodium sulfosuccinate (AOT) solutions on electrode potential (E) and time is measured using three-dimensional phase sensitive ac voltammetry. This methodology, possessing a very wide time window that permits a detailed study of the adsorption phenomena, is based on the reconstruction of C vs E curves, sampled after many phase-sensitive ac chronoamperometric experiments. The shape of these curves allows an estimation of the structure of the layer of AOT molecules absorbed at the electrode surface. AOT molecules form micelles in bulk solutions and they also associate in the charged interface under the strong influence of the electric field into surface aggregates which depend on their concentration and applied potential. The presence of AOT micelles in the bulk solution can be linked with the appearance of a surface film at potentials more negative than those corresponding to a condensed film linked with a capacitance value slightly higher than that normally attributed to a compact layer. The whole phenomenon is proved to be very dependant upon time.

The surgical management of aortic regurgitation in a patient with aortitis is potentially of high risk, especially if it is a reoperation. We present the case of a 59-year-old man for whom coronary artery bypass surgery was not feasible due to structural abnormalities of the aorta and hybrid management was applied. The histopathological examination showed aortitis. One year later, the same patient developed severe aortic regurgitation. In order to minimize the surgical risk of the reoperation we considered all the surgical options. The modified Bentall procedure still seems to be the gold standard in these cases.

The adsorption of sodium dodecylsulphate from aqueous electrolytic solutions on a polarized mercury electrode was studied by means of differential capacitance measurements over a wide range of concentration and potential, and in the presence of different supporting electrolytes with different ionic strengths. An interpretation of the differential capacitance vs. applied potential curves is given, based on theoretical treatments developed previously. It is shown that at concentrations below the cmc, two-dimensional aggregates are formed on the electrode surface within a polarization region which is bounded by two capacitance peaks at extreme positive and negative polarizations. This film is not particularly stable and is transformed into a compact layer at polarizations close to the potential of maximum adsorption, resulting in a capacitance pit. With increasing bulk concentration the aggregation process extends across the interphase and at least two layers of aggregates—micelles are formed at concentrations around and above the cmc. This three-dimensional aggregation is characterized by the appearance of deformed and/or split capacitance peaks which determine the polarization region where this phenomenon occurs.

The adsorption of a cationic micelle—forming surfactant, cetyl—dimethyl-benzylammonium chloride, and of a neutral surfactant, Tween 80 R , from aqueous electrolyte solutions on a polarized mercury electrode was studied by means of differential capacitance measurements in order to examine the influence of the structure and charge of the adsorbate on interfacial micellization. For both surfactants, deformed capacitance peaks were recorded, accompanied by capacitance plateaux. These are sufficient criteria for the occurrence of a two- or three-dimensional aggregation process of the adsorbate molecules within the electrical double layer. The adsorption behaviour of cetyl-dimethyl-benzylammonium cations shows striking similarities with that of sodium dodecylsulphate. Their aggregates on the electrode surface collapse to a compact layer at potentials negative of the ecm and a polylayer is formed under favourable conditions at far negative or positive polarizations respectively. Since these adsorbates have quite different structures, these similarities are attributed to their ionic character. In contrast, the surface aggregates of Tween 80 R do not collapse to a compact layer but are stable over an extended potential range, forming two micellar plateaux. Finally, general conclusions of our theoretical and experimental studies on micellization at charged interphases are also presented.

The penetration of a jet of fluid into a traversal moving stream is a basic configuration of a wide range of engineering applications, such as film cooling and V/STOL aircrafts. This investigation examines experimentally the effect of blowing ratio of fans in crossflow, and numerically, the effect of the swirl velocity of jets in crossflow, downstream of the injection hole. The experimental results indicated an agreement with typically straight jets in crossflow (no vorticity), illustrating that the trace of the jet, remains close to the wall and subsequently enhance cooling at low blowing ratios in the case of turbine blade applications. However, the rotation of the jet results in an imparity between the two parts of the counter rotating vortex pair and as a consequence, the injected fluid not only bends in the direction of the main stream but also diverts in the direction of the rotation in order to conserve its angular momentum. The induction of the swirl velocity on the injected jet destructs one of the two parts of the kidney vortex, which entrains fluid from the crossflow to the jet promoting the mixing between the two fluids while the trace of a swirled jet remains closer to the wall downstream of the injection hole. Finally, the use of contrarotating jet or fan configurations reduces the wall shear stress in a very great extent, leading to better thermal protection of turbine blades, as well as cancels out the yaw torques of each fan separately, resulting in better flight control of typical lift surface. [DOI: 10.1115/1.4002099]

The optimal management of post-intubation tracheal stenoses is surgical reconstruction of the airway. Stenting of the trachea using silastic T-tubes or one of the various types of tracheal stents are the alternative ways to surgical reconstruction for the management of post-intubation tracheal stenoses. The early and long-term results of 11 patients with post-intubation tracheal stenosis, who underwent tracheal stenting with self-expandable metallic stents (SEMSs), are presented.Twelve patients (10 men, mean age: 47.8±20.4 years) with post-intubation tracheal stenosis were referred for tracheal stenting with SEMS (2000-2004). In three cases, the upper tracheal stenosis extended within the subglottic larynx. Stenting was successful in 11 patients, while, in one patient with involvement of the subglottic larynx, the attempt to insert the stent failed. Follow-up time varied from 6 to 96 months, and it was made with virtual and fiberoptic bronchoscopy.Immediate relief of obstructive symptoms was observed in all the 11 patients, where an SEMS was successfully inserted. Stent dislodgement occurred shortly after the procedure in two patients, and it was treated with insertion of a new stent in the first case and a stent-on-stent insertion in the second. Good patency of the stent was observed in three patients for 60-96 months. Three patients with good patency of the stent died from other reasons 24-48 months after stent insertion. Four patients developed obstructive granulation tissue at the ends of the stent after 12-43 months, requiring further treatment with thermal lasers and/or tracheostomy. One patient underwent stent removal and successful laryngotracheal reconstruction 6 months after stent insertion.The application of SEMS in post-intubation tracheal stenoses results in immediate improvement of obstructive symptoms without significant perioperative complications. SEMSs have the potential risks of migration and of granulation tissue formation at the end of the stent. SEMS should be applied only in strictly selected patients with post-intubation tracheal stenosis, who are considered unfit for surgery and/or with limited life expectancy.

An application of classical the thermodynamics is made in the case of surface phase transitions occurring throughout a charged interphase. This kind of surface phase transitions characterizes the aggregation of micelle-forming surfactants within the interphase formed between electrolyte solutions and an ideally polarized electrode, at least at concentrations higher than the critical micelle concentration

The adsorption of cetyl-dimethyl-benzyl ammonium chloride (CDBACI) from aqueous electrolytic solutions on the polarized mercury electrode is studied by means of a recently developed methodology which allows the reconstruction of differential capacitance (C) vs electrode potential (E) curves at various time periods (t). This methodology, which results in C-E-t surfaces and is therefore named Three-Dimensional AC Voltammetry, allows the simultaneous inspection of the time and potential dependence of adsorption processes on mercury. The micelle-forming character of CDBACl in bulk solutions is coupled with the interesting behavior of tetraalkylammonium cations on mercury, leading to extremely rich adsorption behavior with both potential and time variation. This behavior involves compact-layer formation, surface-aggregate formation, and polylayer formation. Some qualitative interpretations for the changes which take place in the adsorption layer in the presence of CDBACl are proposed and discussed.

Three-dimensional phase-sensitive ac voltammetry is proposed as an alternative approach to the study of adsorption from aqueous solutions on mercury with respect to both applied potential and time. The entire curve of differential capacitance C versus applied potential E for various time periods is constructed from isochronous C – E data sampled during many ac phase-sensitive chronoamperometric experiments. The method is used to study the adsorption of sodium dodecyl sulphate from a premicellar solution on a mercury electrode. It is found that the development of the adsorbed film is characterized by strong kinetic effects. These effects are attributed to (a) short time diffusion-controlled processes, (b) phase changes leading to the formation of a compact layer at intermediate polarizations and (c) long time processes due to micellar formation on both sides of the compact layer. The above processes can be distinguished by means of capacitance transients, which are also presented and discussed.

The conductance of dilute solutions of sulfamic acid in water-methanol, water-ethanol and water-isopropanol mixture were measured at 25 °C. The experimental data were processed using the Lee and Wheaton equation to evaluate the limiting conductance Λ0 and association constant Ka. The lowest dielectric constant for each type of water-alcohol mixture was about 20.

OBJECTIVE To report a case of hyperchloremic metabolic acidosis in a patient with beta thalassemia major secondary to treatment with deferasirox due to iron overload. CASE SUMMARY A 58-year-old white female with beta thalassemia major was admitted with fever, fatigue, abnormal liver function test results, and hyperchloremic metabolic acidosis (lactate dehydrogenase 494 U/L, aspartate aminotransferase 167 U/L, alanine aminotransferase 250 U/L, γ-glutamyl transferase 102 U/L, total bilirubin 3.79 mg/dL, direct bilrubin 2.37, potassium 3.3 mEq/L, PO2 81.4 mm Hg, PCO2 29.4 mm Hg, HCO3 16 mEq/L, pH 7.35, chloride 116 mEq/L, anion gap 7.5 mEq/L). Twenty-five days before admission the patient decided to discontinue treatment with deferoxamine for chronic iron overload and continue treatment with oral deferasirox 1500 mg/day. Despite extended clinical and laboratory examination, no obvious cause of fever, hepatitis, or hyperchloremic metabolic acidosis was revealed. Diagnosis was compatible with tubular dysfunction, drug-induced hepatitis, and hypersensitivity reaction due to deferasirox. All pathological findings were fully reversible and our patient had an excellent outcome. DISCUSSION The presence of tubular dysfunction should be considered in any patient with otherwise unexplained hyperchloremic metabolic acidosis. In our patient, other potential causes of metabolic hyperchloremic acidosis were ruled out. Toxic effects of deferasirox are probably caused by chelation of mitochondrial iron, leading to adenosine triphosphate depletion in tubular epithelial cells. Use of the Naranjo probability scale revealed that the adverse reaction was probable. CONCLUSIONS Kidney toxicity may be a major issue in the management of patients receiving deferasirox. Our case indicates a potential risk of renal toxicity with the presence of tubular dysfunction and hyperchloremic metabolic acidosis in patients undergoing treatment with deferasirox.

Background The objectives of the present study were to test the hypothesis that hepatocyte regenerating activity induced by radiofrequency ablation (RFA) of the liver is attenuated when performed under Pringle maneuver, and to investigate the potentially protective effect of mesna prophylactic administration. Materials and Methods Wistar rats were subjected to liver RFA (group RFA), RFA plus Pringle maneuver for 30min (group RFA + P), RFA plus Pringle plus mesna (400mg/kg, per os, 3h prior to operation) (group RFA + P+M), Pringle only (group P), or sham operation (group S) after midline laparotomy. At 1h, liver oxidative state (glutathione to glutathione disulfide ratio–GSH/GSSG) and nuclear factor κB (NF-κB) activity were assessed in liver specimens. At 1, 3, and 6h, the levels of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured in blood serum. At 24h, 48h, 1wk, and 3 wk, the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured in blood serum and the histopathologic profile and hepatocyte mitotic activity were assessed in liver specimens. Results Mitotic activity was low but sustained in groups RFA and RFA + P+M, more intense in group P, while suppressed in group RFA + P. Histopathologic profile was deteriorated with lesions being more intense in group RFA + P but significantly less severe in group RFA + P+M. Oxidative stress was equally induced in all experimental groups. NF-κB was activated in groups RFA, RFA + P, and P, but not in group RFA + P+M. IL-6 and TNF-α serum levels were increased; the levels were significantly higher in group RFA + P, while lower in group RFA + P+M. Serum transaminases levels were increased during the first 48h. Conclusions Hepatocyte regenerating activity is suppressed following liver RFA under Pringle maneuver. Prophylactic administration of mesna preserves hepatocyte regenerating capacity by attenuating acute inflammatory response and minimizing hepatic tissue injury in the non-ablated liver parenchyma.

Background Prolonged sedation with propofol at high doses may lead to fatal multi-organ dysfunction, know as propofol infusion syndrome. We tested the hypothesis that propofol plus remifentanil co-administration attenuates propofol tolerance to its sedative effect and assessed if such an effect has an impact on propofol toxicity in rabbits under prolonged mechanical ventilation. Materials and Methods Eighteen healthy male rabbits were mechanically ventilated and received propofol (group P, n = 6), propofol plus remifentanil (group PR, n = 6), or remifentanil plus sevoflurane (group RS, n = 6) in order to be kept under sedation (group P) or sedation/analgesia (groups PR and RS) for up to 48h. Initial propofol and remifentanil infusion rates (IRs) were adjusted, if needed, to maintain the desired level of sedation and analgesia, respectively (groups P and PR). In group RS, remifentanil was infused at IRs equivalent to those of group PR. Propofol IRs were recorded, propofol concentrations were measured in the arterial plasma, and blood biochemical parameters and organ histopathology were assessed. Results Animals survived for 29-36h in group P and 22-38h in group PR (100% mortality rate). Tolerance was developed to propofol's sedative effect. The onset of tolerance was delayed and its magnitude was decreased in group PR compared with group P. Propofol was accumulated in the systemic circulation. Propofol clearance rate was gradually decreased. Arterial lactate, and serum aspartate aminotransferase (AST), lactate dehydrogenase (LDH), bilirubin, cholesterol, triglycerides, and creatine kinase (CK) levels were increased. The heart, lungs, liver, gallbladder, kidneys, urinary bladder, and skeletal muscles were seriously injured in groups P and PR. In group RS, mortality was 0%, while there was only mild injury of the lungs, liver, gallbladder, kidneys, and urinary bladder. Conclusions Although propofol tolerance is attenuated in propofol plus remifentanil receiving rabbits under prolonged mechanical ventilation, fatal multi-organ injury occurs resembling human propofol infusion syndrome.

A potentiostat and a drop knocker have been interfaced to a Macintosh2 computer, using Labview2 for the programming of the interface. The whole system can perform the functions of a pulse polarograph. Digital storage of the experimental data permits baseline substraction and digital filtering at the end of the experiment.

The electrochemical reduction of o -benzoquinone dioxime ( o -BQD) at a Pt/Bi(upd) electrode was studied in aqueous acid solutions. The reduction follows the ECECE mechanism, where the chemical reactions are the dehydration of unstable hydroxylamine intermediates. The ECECE sequence was characterized by means of cyclic, rotating-disc and ring-disc voltammetry. The exact rate constants were determined by means of an iterative method using chronoamperometric data.

The possibility of three dimensional electrochemistry being implemented in a routine use for elucidation of electrochemical reactions using computerized instrumentation has been studied. Three dimensional voltammograms based on chronoamperometric data have been used for the elucidation of the kinetics and mechanism of the reduction and oxidation processes of tetrahydroxy-1,4-benzoquinone. The study was carried out in aqueous 0.5 M HClO 4 , solutions on Pt and Pt/M(upd) (M == Tl, Bi) electrodes. The present results are compared with those reported previously which were obtained employing rotating-disc and ring-disc techniques and the applicability of the proposed method is confirmed by these results.

Summary Background Results of several studies published since 1999 suggest that primary hyperaldosteronism (also known as Conn's syndrome) affects more than 10% of people with hypertension; however, such a high prevalence has also been disputed. Experts generally agree that resistant hypertension has the highest prevalence of primary hyperaldosteronism, on the basis of small studies. We aimed to assess the prevalence of primary hyperaldosteronism in a large group of patients with resistant hypertension. Methods Patients with resistant hypertension (blood pressure >140/90 mm Hg despite a three drug regimen, including a diuretic) who attended our outpatient clinic were assessed for primary hyperaldosteronism. Serum aldosterone and plasma renin activity were determined and their ratio was calculated. Patients with a positive test (ratio >65·16 and aldosterone concentrations >416 pmol/L) underwent salt suppression tests with intravenous saline and fludrocortisone. Diagnosis of primary hyperaldosteronism was further confirmed by the response to treatment with spironolactone. Findings Over 20 years, we studied 1616 patients with resistant hypertension. 338 patients (20·9%) had a ratio of more than 65·16 and aldosterone concentrations of more than 416 pmol/L. On the basis of salt suppression tests, 182 (11·3%) patients had primary hyperaldosteronism, and response to spironolactone treatment further confirmed this diagnosis. Hypokalaemia was seen only in 83 patients with primary hyperaldosteronism (45·6%). Interpretation Although the prevalence of primary hyperaldosteronism in patients with resistant hypertension was high, it was substantially lower than previously reported. On the basis of this finding, we could assume that the prevalence of primary hyperaldosteronism in the general unselected hypertensive population is much lower than currently reported. Thus, the notion of an epidemic of primary hyperaldosteronism is not supported. Funding None.

The aim of the study was to determine the importance of genetic polymorphisms of glutathione-S-transferase T1 and M1 and cytochrome P1A1 genes in the development of cervical intraepithelial neoplasia in Greek women. This was a prospective, case-control study conducted by the Cervical Pathology and Colposcopy Unit of a University Ob/Gyn Department from 1999 to 2003. Cervical smears from 114 controls without any cytological and/or colposcopical evidence of cervical pathology and from 166 women with history of cervical intraepithelial neoplasia (56 CIN I, 54 CIN II and 56 CIN III) were examined with polymerase chain reaction for the above-mentioned genetic polymorphisms, taking also in mind their smoking attitudes. Statistical analysis was performed to detect any association between the null genotype of GSTM1 and GSTT1 genes and the CYP1A1 m1 polymorphism and the severity of cervical intraepithelial neoplasia. The distributions of the GSTT1 and GSTM1 wild-type genotypes were 57.48 and 39.75%, respectively. No woman with homozygous GSTT1 and GSTM1 null/null genotype was identified. CYP1A1 m1 polymorphism frequency was 24.49%. No woman with homozygous CYP1A1 m1/m1 genotype was detected as well. No significant difference in the frequencies of the GSTM1 and GSTT1 null alleles, and the CYP1A1 m1 polymorphism, was found between cases and controls. After application of Mantel-Haenszel chi procedure, there was no linear severity of the lesion and the frequency of these polymorphisms. According to our results, glutathione-S-transferase T1 and M1 and cytochrome P1A1 genetic polymporphisms do not appear to be a risk factor for cervical disease irrespective of smoking habits.

Metastatic tumors make up approximately one percent of all oral malignancies. Such tumors may present in the jaw bones and oral soft tissues. The commonest oral site is the mandible.This is a retrospective study of four cases of metastatic tumors of the jaws seen at the Oral-Maxillofacial Department, General University Hospital of Alexandroupolis, Thrace, Greece from 1989 to 2005, representing 1% of all histologically confirmed malignant tumors at the hospital.Two cases originated from the thyroid gland, one was from the esophagus, and one from the liver. Three metastases occurred in the mandible and one in the maxilla. The oral symptoms were similar to odontogenic infections or to benign neoplasms.In view of the resemblance in the presentation of metastases and other tumors affecting the jaws, a high index of clinical suspicion is advocated to ensure early, multidisciplinary care of hosts.

Background Radiofrequency ablation (RFA) of the liver leads to reduction of liver parenchymal volume. We sought to evaluate the regenerative response of the liver following RFA. Materials and Methods Thirty healthy New Zealand white rabbits were subjected to a single session liver RFA using a cool-tip electrode after midline laparotomy. The regenerative process of the liver was assessed at various time-points (0 h, 48 h, 1 wk, 3 wk, 10 wk) in terms of computed tomography-based liver volume measurements, histological examination, hepatocyte mitotic activity, and serum biochemistry. Results According to computed tomography-measurements, intact liver volume was gradually restored to the initial liver volume by the 10th week, while liver ablated volume was confined down to 50% of the initial ablated volume. At histology, inflammation, edema, and hepatocellular necrosis in the intact liver parenchyma, noted at 48 h, started to regress by 1 wk. Mitotic activity, initiated by 48 h, was substantially increased at 1 wk and remained high up to the 10th week. Serum transaminase levels were elevated up to 1 wk. Conclusions Liver RFA triggers a slow but sustained regenerative response of the liver with subsequent delayed restoration of parenchymal volume, while the ablated volume is gradually condensed.

Hysteroscopic guided or first generation endometrial ablation methods include transcervical endometrial resection, and rollerball and laser ablation. These techniques have been shown to be effective and safe alternatives to hysterectomy for dysfunctional uterine bleeding resulting in reduction in menstrual blood loss and dysmenorrhoea, correction of anaemia and improvement in quality of life. Compared with hysterectomy, treatment is associated with lower morbidity, shorter hospitalisation and faster recovery, and reduced treatment costs. As a result, the 1st generation ablation techniques are recognized as the "gold standard" ablation methods. There are many similarities between the three techniques with respect to surgical principles and effectiveness. Certainly, menstrual improvement and patient satisfaction are similar with all three methods. In contrast, the complication profile of the three techniques is different, but surgical experience is arguably a much more important arbiter of patient safety than the technique itself.

Background. Injury to major retroperitoneal vessels is the most catastrophic complication of laparoscopy. Knowledge of the site of the aortic bifurcation prior to inserting the umbilical port would be expected to reduce the risk of this type of injury. The aim of the study is to determine the feasibility of identifying the aortic bifurcation by palpation prior to the operation. Methods. We studied 100 patients undergoing laparoscopic surgery or laparotomy. After prepping and draping, the operating surgeon felt for the aortic bifurcation to determine its position in relation to the umbilicus. We then related our findings to the height, weight, and body mass index of the patient. Results. The aorta could not be palpated in 15% of cases, including almost 2/3 of women who were obese (body mass index >30). In the remaining 85% cases, where the aorta was palpable, the bifurcation was above the level of the umbilicus in 30 (35%) cases, at the umbilicus in 45 (53%) cases, and below in 10 (12%) cases. We did not find any significant effect of body mass index, height, or weight on the level of the aortic bifurcation by palpation. No vascular injury occurred in the laparoscopic cases during the study. Conclusions. The aortic bifurcation is palpable in the majority of women undergoing surgery, including 93% of those with a low or normal body mass index who are at higher risk of vascular injury. We recommend the routine palpation for the aortic bifurcation as a simple means to reduce the risk of injury to a major retroperitoneal vessel.

A S L D A b st ra ct s diagnosed with chronic hepatitis B (ICD-9-CM codes 070.2 and 070.3) at our institution during 2011-2014. In addition to patient demographics, characteristics of chronic hepatitis B and treatment patterns were examined. The chi-square test and multivariate logistic model were used in statistical analysis. Results: Our study sample of 111 chronic hepatitis B patients included 66 Asians, 18 African Americans, and 27 other races, with mean age of 46.7 (standard deviation 12.6), 61.3% female, 2.7% with family history of HCC, and 3.6% cirrhotic. Eighteen patients (16.2%) reported at least occasional alcohol use and 49 patients (44.1%) were treated with an anti-HBV medication, mainly tenofovir (n=36) followed by entecavir (n=9). Fifty two patients (46.8%) were deemed at high risk for HCC per the AASLD guideline, of which 51 patients (98.1%) underwent or were recommended to undergo an imaging study (ultrasound, CT or MRI) at their most recent visit. Use of anti-HBV medication was positively associated with age and cirrhosis (both p

Imprint cytology may provide a fast and accurate method for intraoperative screening of sentinel lymph nodes, so a decision can be made regarding whether to perform axillary clearance during primary surgery. If the findings are negative, in many cases axillary dissection can be omitted.128 sentinel nodes from a cohort of 87 patients that had been identified using technetium-99m nanocolloid as a radioactive tracer and Patent blue dye were dissected for rapid Diff-Quick stained touch preparations. Intraoperative evaluation of sentinel node status by imprint cytology was correlated with histopathological results of permanent sections. Tumor-negative nodes in routine paraffin sections were further investigated with the employment of an anti-cytokeratin antibody.36 of all sentinel nodes harbored metastases in the paraffin sections, of which 32 were identified by imprint cytology (sensitivity 88.8%). 3 sentinel nodes were positive by imprint cytology and negative by histopathology of the paraffin sections. Comparison of the results of the touch preparations with the final histopathology (hematoxylin-eosin and anticytokeratin antibody stains) demonstrated a sensitivity of 83.3% and a negative predictive value of 92.5%. The specificity and positive predictive value were 100% each.Touch imprint cytology is potentially useful for intraoperative evaluation of sentinel lymph nodes in breast cancer patients.

The impact of the light illumination on the drain current of polycrystalline silicon thin-film transistors is studied in this work. The increase of the output current as a result of raised light intensity is modeled, based on measured experimental data for different V/sub ds/, V/sub gs/ values and transistor sizes W/L. The proposed model has been verified against the measurements and the simulated output characteristics give a good approximation in the sub-threshold region.

The adnexa frequently hinder access to the pelvic side wall during laparoscopic surgery for endometriosis. An innovative tactic can facilitate dissection.

The sites of haematopoiesis during human ontogeny can be correlated to the sites where haematopoiesis occurs in vertebrate phylogeny. As haematopoiesis has been described in the diencephalon and pituitary gland of water-inhabiting vertebrates we wanted to find out whether such a phenomenon also occurs in human embryos.Paraffin-embedded specimens from the diencephalon and pituitary gland of human embryos at the 7th to 22nd gestational week and from adults were investigated by conventional histology and immunohistology for the presence of haematopoietic cells.Cellular accumulations predominantly of erythroid and megakaryocytic lineage were identified in the floor of the developing diencephalon of the 7th/8th gestational week. At the older developmental stages of the 18th to 22nd gestational week loose aggregates of haematopoietic cells within the leptomeningeal spaces adjacent to the hypophyseal infundibulum were detected in 2 out of 7 cases analyzed.As it has been proposed that lymphohaematopoietic clusters occasionally occur within the brain in bone marrow-less vertebrates as a response to noxious agents, we speculate that this temporal appearance of haematopoietic cell clusters within the diencephalon floor in early human ontogeny could also be due to fetal immunomodulations.