Differentiating Simple Hepatic Cysts from Mucinous Cystic Neoplasms: Radiological Features, Cyst Fluid Tumour Marker Analysis and Multidisciplinary Team Outcomes

Background: Differentiating hepatic mucinous cystic neoplasms (MCNs) from simple hepatic cysts (SCs) preoperatively is a challenging task. Our aim was to determine whether radiological features on ultrasound scan (USS), CT or MRI, cyst fluid tumour markers, or multidisciplinary team (MDT) outcomes could differentiate MCN from SC. Methods: A retrospective review of radiological features, cyst fluid tumour marker levels and MDT outcomes in 52 patients was performed. Results: There were 13 patients with MCN, 38 with SC and one ciliated foregut cyst. MCNs were more often solitary (p = 0.006). Although no other individual radiological characteristic on USS, CT or MRI was predictive of MCN, MDT outcomes stating that a cyst was complex in nature were highly predictive (p = 0.0007). Cyst fluid carbohydrate antigen 19-9, carcino-embryonic antigen and cancer antigen 125 were unable to differentiate MCN from SC (p = 0.45, p = 0.49, and p = 0.73, respectively). Conclusions: MDT outcomes are of greatest value when trying to differentiate MCN from SC, as well as having a solitary cyst on imaging. Conventional cyst fluid tumour markers are unhelpful. All suspicious cystic liver lesions should be discussed pre-operatively by a hepatobiliary MDT to determine the most appropriate surgical approach

Concurrent Acquisition of a Single Nucleotide Polymorphism in Diverse Influenza H5N1 Clade 2.2 Sub-clades

Highly pathogenic Influenza A H5N1 was first identified in Guangdong Province in 1996, followed by human cases in Hong Kong in 1997. The number of confirmed human cases now exceeds 300, and the associated Case Fatality Rate exceeds 60%. The genetic diversity of the serotype continues to increase. Four distinct clades or sub-clades have been linked to human cases. The gradual genetic changes identified in the sub-clades have been attributed to copy errors by viral encoded polymerases that lack an editing function, thereby resulting in antigenic drift. We report here the concurrent acquisition of the same polymorphism by multiple, genetically distinct, clade 2.2 sub-clades in Egypt, Russia, and Ghana. These changes are not easily explained by the current theory of “random mutation” through copy error, and are more easily explained by recombination with a common source. This conclusion is supported by additional polymorphisms shared by clade 2.2 isolates in Egypt and Germany

Independent Ion Migration in Suspensions of Strongly Interacting Charged Colloidal Spheres

We report on sytematic measurements of the low frequency conductivity in aequous supensions of highly charged colloidal spheres. System preparation in a closed tubing system results in precisely controlled number densities between 1E16/m3 and 1E19/m^3 (packing fractions between 1E-7 and 1E-2) and electrolyte concentrations between 1E-7 and 1E-3 mol/l. Due to long ranged Coulomb repulsion some of the systems show a pronounced fluid or crystalline order. Under deionized conditions we find s to depend linearily on the packing fraction with no detectable influence of the phase transitions. Further at constant packing fraction s increases sublinearily with increasing number of dissociable surface groups N. As a function of c the conductivity shows pronounced differences depending on the kind of electrolyte used. We propose a simple yet powerful model based on independent migration of all species present and additivity of the respective conductivity contributions. It takes account of small ion macro-ion interactions in terms of an effectivly transported charge. The model successfully describes our qualitatively complex experimental observations. It further facilitates quantitative estimates of conductivity over a wide range of particle and experimental parameters.Comment: 32 pages, 17 figures, 2 tables, Accepted by Physical Review

Allergenicity of gutta-percha and the potential sensitization from latex products : (an animal study)

Thesis (M.S.D.)--Boston University, Henry M. Goldman School of Dental Medicine, 2003 (Endodontics).Includes bibliography (leaves 116-130).Introduced in dentistry more than 100 years ago, gutta-percha is the material of choice for root canal obturation, demonstrating minimal toxicity and tissue irritation. With the erupting incidences of latex allergies, there was a concern about the potential for immunoIogical cross-reactivity between gutta-percha and natural rubber latex. Gutta-percha is a rubber-like hydrocarbon derived from the sap of Payena and Palaquium gutta trees that are of the same botanical family as the Havea Brasiliensis trees that produce natural rubber latex. Gutta-percha is an isoprene polymer of a trans-arrangement, whose chemical composition is similar to the cis-polyisoprene of latex. One aim of this study was to test for this cross-reactivity. A total of twenty-two (22) female Dunkin-Hartley guinea pigs were divided into seven (7) groups. Two groups received latex implants subcutaneously, with one group getting a latex patch and the other getting a gutta-percha patch. Two groups received gutta-percha implants subcutaneously, with one group getting a latex patch and the other getting a gutta-percha patch. The remaining three groups were control groups. Two were negative controls, one receiving latex patches and the other receiving gutta-percha patches. The last group was the positive group receiving latex protein injected subcutaneously and latex paint on the skin of the animal. The implanted materials were left for fourteen (14) days before the patches were applied. The patches were placed for three (3) days before the animals were euthanised. Blood samples were drawn on days 1 and 14 (before placing the patches), day 14 six hours after placing the patches, and on day 15 and 16. After the animals were euthanised, tissue samples were obtained where the patches were applied and where the materials were implanted. H&E stained slides were prepared. The blood samples were analyzed by Western blot assay. The clinical, histological and immunological results indicated that there was no cross-reactivity between latex and gutta-percha. No detectable allerginicity for gutta-percha was observed however inflammatory reaction in tissue around implanted latex and gutta-percha was detected. It was concluded that the commercial gutta-percha tested did not contain the extractable proteins that can cross-react with latex. However if gutta-balata is added to the manufactured gutta-percha, caution should be considered when using this product to obturate root canals in latex-allergic patients

Design of an electrochemical micromachining machine

Electrochemical micromachining (μECM) is a non-conventional machining process based on the phenomenon of electrolysis. μECM became an attractive area of research due to the fact that this process does not create any defective layer after machining and that there is a growing demand for better surface integrity on different micro applications including microfluidics systems, stress-free drilled holes in automotive and aerospace manufacturing with complex shapes, etc. This work presents the design of a next generation μECM machine for the automotive, aerospace, medical and metrology sectors. It has three axes of motion (X, Y, Z) and a spindle allowing the tool-electrode to rotate during machining. The linear slides for each axis use air bearings with linear DC brushless motors and 2-nm resolution encoders for ultra precise motion. The control system is based on the Power PMAC motion controller from Delta Tau. The electrolyte tank is located at the rear of the machine and allows the electrolyte to be changed quickly. This machine features two process control algorithms: fuzzy logic control and adaptive feed rate. A self-developed pulse generator has been mounted and interfaced with the machine and a wire ECM grinding device has been added. The pulse generator has the possibility to reverse the pulse polarity for on-line tool fabrication.The research reported in this paper is supported by the European Commission within the project “Minimizing Defects in Micro-Manufacturing Applications (MIDEMMA)” (FP7-2011-NMPICT- FoF-285614)

The Effects of Cocaine on Different Redox Forms of Cysteine and Homocysteine, and on Labile, Reduced Sulfur in the Rat Plasma Following Active versus Passive Drug Injections

Received: 28 November 2012 / Revised: 19 April 2013 / Accepted: 6 May 2013 / Published online: 16 May 2013 The Author(s) 2013. This article is published with open access at Springerlink.comThe aim of the present studies was to evaluate cocaine-induced changes in the concentrations of different redox forms of cysteine (Cys) and homocysteine (Hcy), and products of anaerobic Cys metabolism, i.e., labile, reduced sulfur (LS) in the rat plasma. The above-mentioned parameters were determined after i.p. acute and subchronic cocaine treatment as well as following i.v. cocaine self-administration using the yoked procedure. Additionally, Cys, Hcy, and LS levels were measured during the 10-day extinction training in rats that underwent i.v. cocaine administration. Acute i.p. cocaine treatment increased the total and protein-bound Hcy contents, decreased LS, and did not change the concentrations of Cys fractions in the rat plasma. In turn, subchronic i.p. cocaine administration significantly increased free Hcy and lowered the total and protein-bound Cys concentrations while LS level was unchanged. Cocaine self-administration enhanced the total and protein-bound Hcy levels, decreased LS content, and did not affect the Cys fractions. On the other hand, yoked cocaine infusions did not alter the concentration of Hcy fractions while decreased the total and protein-bound Cys and LS content. This extinction training resulted in the lack of changes in the examined parameters in rats with a history of cocaine self-administration while in the yoked cocaine group an increase in the plasma free Cys fraction and LS was seen. Our results demonstrate for the first time that cocaine does evoke significant changes in homeostasis of thiol amino acids Cys and Hcy, and in some products of anaerobic Cys metabolism, which are dependent on the way of cocaine administration

Aggregation of Single Nucleotide Polymorphisms in a Human H5N1 Clade 2.2 Hemagglutinin

The evolution of H5N1 has attracted significant interest 1-4 due to linkages with avian 5,6 and human infections 7,8. The basic tenets of influenza genetics 9 attribute genetic drift to replication errors caused by a polymerase complex that lacks a proof reading function. However, recent analysis 10 of swine influenza genes identifies regions copied with absolute fidelity for more than 25 years. In addition, polymorphism tracing of clade 2.2 H5N1 single nucleotide polymorphisms identify concurrent acquisition 11 of the same polymorphism onto multiple genetic backgrounds in widely dispersed geographical locations. Here we show the aggregation of regional clade 2.2 polymorphisms from Germany, Egypt, and sub-Sahara Africa onto a human Nigerian H5N1 hemagglutinin (HA), implicating recombination in the dispersal and aggregation of single nucleotide polymorphisms from closely related genomes

Aggregation of Single Nucleotide Polymorphisms in a Human H5N1 Clade 2.2 Hemagglutinin

The rapid evolution of the H5N1 serotype of avian influenza has been explained by a mechanism involving the selection of single nucleotide polymorphisms generated by copy errors. The recent emergence of H5N1 Clade 2.2 in fifty countries, offered a unique opportunity to view the acquisition of new polymorphism in these evolving genomes. We analyzed the H5N1 hemagglutinin gene from a fatal human case from Nigeria in 2007. The newly emerged polymorphisms were present in diverse H5N1 isolates from the previous year. The aggregation of these polymorphisms from clade 2.2 sub-clades was not supported by recent random mutations, and was most easily explained by recombination between closely related sequences