Endoscopic sinus surgery for maxillary sinus mucoceles

BACKGROUND: Maxillary sinus mucoceles are relatively rare among all paranasal sinus mucoceles. With the introduction of endoscopic sinus surgical techniques, rhinologic surgeons prefer transnasal endoscopic management of sinus mucoceles. The aim of this study is to describe the clinical presentation of maxillary sinus mucoceles and to establish the efficacy of endoscopic management of sinus mucoceles. METHODS: Between 2003 and 2005, 14 patients underwent endoscopic sinus surgery for maxillary sinus mucocele. The presenting sign and symptoms, radiological findings, surgical management and need for revision surgery were reviewed. RESULTS: There were eight males and six females with an age range of 14 to 65. Ten patients complained of nasal obstruction, five of nasal drainage, five of cheek pressure or pain and one of proptosis of the eye and cheek swelling. The maxillary sinus and ipsilateral ethmoid sinus involvement on computed tomographic studies was seen in 4 patients. Four patients had history of endoscopic ethmoidectomy surgery for ethmoid sinusitis and one had Caldwell-Luc operation in the past. Ethmoidectomy with middle meatal antrostomy and marsupialization of the mucocele was performed in all patients. Postoperative follow-up ranged between 8 to 48 months. All patients had a patent middle meatal antrostomy and healthy maxillary sinus mucosa. No patients need revision surgery. CONCLUSION: The most common causes of mucoceles are chronic infection, allergic sinonasal disease, trauma and previous surgery. In 64% of the patients of our study cause remains uncertain. Endoscopic sinus surgery is an effective treatment for maxillary sinus mucoceles with a favorable long-term outcome

DMSO and Betaine Greatly Improve Amplification of GC-Rich Constructs in De Novo Synthesis

In Synthetic Biology, de novo synthesis of GC-rich constructs poses a major challenge because of secondary structure formation and mispriming. While there are many web-based tools for codon optimizing difficult regions, no method currently exists that allows for potentially phenotypically important sequence conservation. Therefore, to overcome these limitations in researching GC-rich genes and their non-coding elements, we explored the use of DMSO and betaine in two conventional methods of assembly and amplification. For this study, we compared the polymerase (PCA) and ligase-based (LCR) methods for construction of two GC-rich gene fragments implicated in tumorigenesis, IGF2R and BRAF. Though we found no benefit in employing either DMSO or betaine during the assembly steps, both additives greatly improved target product specificity and yield during PCR amplification. Of the methods tested, LCR assembly proved far superior to PCA, generating a much more stable template to amplify from. We further report that DMSO and betaine are highly compatible with all other reaction components of gene synthesis and do not require any additional protocol modifications. Furthermore, we believe either additive will allow for the production of a wide variety of GC-rich gene constructs without the need for expensive and time-consuming sample extraction and purification prior to downstream application

Visual gene developer: a fully programmable bioinformatics software for synthetic gene optimization

<p>Abstract</p> <p>Background</p> <p>Direct gene synthesis is becoming more popular owing to decreases in gene synthesis pricing. Compared with using natural genes, gene synthesis provides a good opportunity to optimize gene sequence for specific applications. In order to facilitate gene optimization, we have developed a stand-alone software called Visual Gene Developer.</p> <p>Results</p> <p>The software not only provides general functions for gene analysis and optimization along with an interactive user-friendly interface, but also includes unique features such as programming capability, dedicated mRNA secondary structure prediction, artificial neural network modeling, network & multi-threaded computing, and user-accessible programming modules. The software allows a user to analyze and optimize a sequence using main menu functions or specialized module windows. Alternatively, gene optimization can be initiated by designing a gene construct and configuring an optimization strategy. A user can choose several predefined or user-defined algorithms to design a complicated strategy. The software provides expandable functionality as platform software supporting module development using popular script languages such as VBScript and JScript in the software programming environment.</p> <p>Conclusion</p> <p>Visual Gene Developer is useful for both researchers who want to quickly analyze and optimize genes, and those who are interested in developing and testing new algorithms in bioinformatics. The software is available for free download at <it><url>http://www.visualgenedeveloper.net</url></it>.</p

Metabolomic and transcriptomic analysis of the rice response to the bacterial blight pathogen Xanthomonas oryzae pv. oryzae

Bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), gives rise to devastating crop losses in rice. Disease resistant rice cultivars are the most economical way to combat the disease. The TP309 cultivar is susceptible to infection by Xoo strain PXO99. A transgenic variety, TP309_Xa21, expresses the pattern recognition receptor Xa21, and is resistant. PXO99△raxST, a strain lacking the raxST gene, is able to overcome Xa21-mediated immunity. We used a single extraction solvent to demonstrate comprehensive metabolomics and transcriptomics profiling under sample limited conditions, and analyze the molecular responses of two rice lines challenged with either PXO99 or PXO99△raxST. LC–TOF raw data file filtering resulted in better within group reproducibility of replicate samples for statistical analyses. Accurate mass match compound identification with molecular formula generation (MFG) ranking of 355 masses was achieved with the METLIN database. GC–TOF analysis yielded an additional 441 compounds after BinBase database processing, of which 154 were structurally identified by retention index/MS library matching. Multivariate statistics revealed that the susceptible and resistant genotypes possess distinct profiles. Although few mRNA and metabolite differences were detected in PXO99 challenged TP309 compared to mock, many differential changes occurred in the Xa21-mediated response to PXO99 and PXO99△raxST. Acetophenone, xanthophylls, fatty acids, alkaloids, glutathione, carbohydrate and lipid biosynthetic pathways were affected. Significant transcriptional induction of several pathogenesis related genes in Xa21 challenged strains, as well as differential changes to GAD, PAL, ICL1 and Glutathione-S-transferase transcripts indicated limited correlation with metabolite changes under single time point global profiling conditions

Review On Development Of Natural Rubber/Nanoclay Nanocomposites

The advantages of nanocomposites containing single silicate layers uniformly dispersed in a polymer matrix were first demonstrated by researchers at Toyota in Japan, who developed nylon-6 nanocomposites and published in 1993. Polymer-nanoclay nanocomposites have attracted the attention of many researchers thereafter due to their outstanding mechanical and barrier properties. This concept is first applied to synthesis of plastics/nanoclay nanocomposites and then expanded to preparation of rubber/nanoclay nanocomposites, since few years later. The various types of synthetic rubbers, such as silicon rubber, nitrile rubber and epoxy rubber, were used to prepare nanocomposites using different techniques, namely, melt intercalation, in situ intercalative polymerization, exfoliationadsorption and template synthesis, etc. Natural rubber (NR) was also used to prepare nanocomposites using the same techniques but with some modifications in the last decade. Now a day’s nanocomposites are widely developed in NR latex industry to achieve required properties with minimum use of clay content. NR/nanoclay nanocomposites exhibit markedly improved properties when compared to pure NR or their traditional composites. Most notable properties are increased tensile properties, gas barrier properties and heat distortion temperature, resistance to small molecule permeation, increase in atomic oxygen resistance and retention of impact strength. Tensile strength and modulus were recorded in current research as enhanced by more than two times or even ten times. It was noticed that obtaining a fully exfoliated structure is not at the desired level. Nanoclay nanocomposites are considered as fully exfoliated when inter gallery distance is greater than 10 nm but it was not achieved in many research work. Establishment of exfoliated structures in nanocomposites prepared in industrial scale is the major challenge that NR industry faces at present. NR/nanoclay nanocomposites produced with existing techniques develop high property fluctuations. Therefore, it is necessary to develop a technique to minimize property fluctuations and to obtain a reliable NR based product. It is predicted by this review that co-coagulation technique is the most promising and potential technique to fulfill the requirements of developing a NR/nanoclay nanocomposite. Use of modified nanoclays like Organoclays will aid to obtain a reliable NR based product.IEEE IEEE Sri Lanka Section Robotics and Automation Section Chapter, IEEE Sri Lanka Sectio

Review on development of natural rubber/nanoclay nanocomposites

The advantages of nanocomposites containing single silicate layers uniformly dispersed in a polymer matrix were first demonstrated by researchers at Toyota in Japan, who developed nylon-6 nanocomposites and published in 1993. Polymer-nanoclay nanocomposites have attracted the attention of many researchers thereafter due to their outstanding mechanical and barrier properties. This concept is first applied to synthesis of plastics/nanoclay nanocomposites and then expanded to preparation of ubber/nanoclay nanocomposites, since few years later. The various types of synthetic rubbers, such as silicon rubber, nitrile rubber and epoxy rubber, were used to prepare nanocomposites using different techniques, namely, melt intercalation, in situ intercalative polymerization, exfoliationadsorption and template synthesis, etc. Natural rubber (NR) was also used to prepare nanocomposites using the same techniques but with some modifications in the last decade. Now a day’s nanocomposites are widely developed in NR latex industry to achieve required properties with minimum use of clay content. NR/nanoclay nanocomposites exhibit markedly improved properties when compared to pure NR or their traditional composites. Most notable properties are increased tensile properties, gas barrier properties and heat distortion temperature, resistance to small molecule permeation, increase in atomic oxygen resistance and retention of impact strength. Tensile strength and modulus were recorded in current research as enhanced by more than two times or even ten times. It was noticed that obtaining a fully exfoliated structure is not at the desired level. Nanoclay nanocomposites are considered as fully exfoliated when inter gallery distance is greater than 10 nm but it was not achieved in many research work. Establishment of exfoliated structures in nanocomposites prepared in industrial scale is the major challenge that NR industry faces at present. NR/nanoclay nanocomposites produced with existing techniques develop high property fluctuations. Therefore, it is necessary to develop a technique to minimize property fluctuations and to obtain a reliable NR based product. It is predicted by this review that co-coagulation technique is the most promising and potential technique to fulfill the requirements of developing a NR/nanoclay nanocomposite. Use of modified nanoclays like Organoclays will aid to obtain a reliable NR based product