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Investigates the role of template in enzymatic synthesis of conducting polyaniline. Mechanistic role of the template in the reaction; Preparation of water soluble conducting polyaniline using a novel template-guided enzymatic approach; Intercalation of the micelle systems between the sulfonated styrene headgroups of the micelles.

Pyogenic granuloma is thought to represent an exuberant tissue response to a local irritation or trauma. It is a reactional response to constant minor trauma and it might be related to hormonal changes. Clinically, these lesions usually present as single nodules or sessile papules with smooth or lobulated surfaces. These may be seen in any size, from a few millimetres to several centimetres. Pyogenic granuloma of the oral cavity is known to involve the gingiva more commonly (75% of all the cases). An extragingival occurrence of pyogenic granuloma is rare. This paper has described an extragingival pyogenic granuloma which occurred on the upper labial mucosa in a 30 years old female patient. [ABSTRACT FROM AUTHOR]

Severe pulmonary hypertension in a teenager with end-stage renal disease on chronic hemodialysis via arteriovenous access is reported. Clinical presentation included persistent volume overload and pericardial effusion. Serial hemodynamic data obtained at cardiac catheterization confirmed the diagnosis. In addition, detailed biochemical and imaging data (echo- Doppler, computed tomography of chest, computed tomographic pulmonary angiography, VQ lung scan, etc.) were obtained to find out the mechanism. The exact cause of pulmonary hypertension remains unclear, and a multi- factorial mechanism is postulated. This rare case is presented to highlight the role of aggressive dialysis, pericardiocentesis, and use of sildenafil and bosentan in the management. [ABSTRACT FROM AUTHOR]

Objectives: Pericoronitis of mandibular third molars is commonly encountered in our day to day practice. Most of the case extraction becomes mandatory. This study was carried out to find the incidence of periodontitis on the distal aspect of the second molar adjacent to impacted third molar. Materials and Methods: A total of 400 patients were included in the study. Patient selection was randomly done. Whoever came with a chief complaint of pain in the third molar area were included in the study. They were evaluated both clinically and radiographically with an orthopantomogram. Patients' age, gender, type of impaction, presence or absence of bone loss, type of bone loss, and presence or absence of caries was evaluated radiographically and noted. Results: Periodontitis was observed in 39% of the cases and caries in 26% of the cases. Conclusions: These percentages are alarming and could be used to prophylactically extract the impacted third molars and thereby promoting the oral health of the individual. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about a study which reveals the predictive role of endoscopy in dysphagia with associated symptoms.

Both adenosine (ADO) and ATP dependent potassium (KATP) channels have been shown to be involved in arteriolar dilations in response to repetitive muscle contraction. A single muscle contraction can produce a dilatory response characterized by an initial, rapid dilation followed by a secondary, prolonged dilation using specific skeletal muscle stimulation parameters. To investigate the role of ADO and KATP channels in the secondary dilation we stimulated 4-5 skeletal muscle fibres in the anaesthetized hamster cremaster preparation in situ and measured the change in diameter of arterioles (max. diameter approx. 40um) at the site of overlap with the stimulated muscle fibres before and after a single contraction (250ms train duration) at 4, 20 and 60Hz stimulus frequencies. Muscle fibres were stimulated prior to and following 30min incubation with xanthine amine congener (XAC, ADO receptor antagonist, 10-6M) or glibenclamide (GLIB, KATP channel inhibitor, 10-5 M). A significant secondary dilation between 20-40s was not observed at 4Hz. A significant secondary dilation was observed between 20-40s at 20 and 60 Hz (1.3+/-0.1um and 1.1+/-0.1um respectively) which was significantly decreased by XAC (0.2+/-0.1um and 0.3+/-0.1um) and GLIB (0.4+/-0.1um and 0.3+/-0.1um). Therefore both ADO and KATP channels appear to be involved in the secondary dilation in response to a single muscle contraction. [ABSTRACT FROM AUTHOR]

In the current study, we investigated windows for enhanced learning of cognitive skills during adolescence. Six hundred thirty-three participants (11-33 years old) were divided into four age groups, and each participant was randomly allocated to one of three training groups. Each training group completed up to 20 days of online training in numerosity discrimination (i.e., discriminating small from large numbers of objects), relational reasoning (i.e., detecting abstract relationships between groups of items), or face perception (i.e., identifying differences in faces). Training yielded some improvement in performance on the numerosity-discrimination task, but only in older adolescents or adults. In contrast, training in relational reasoning improved performance on that task in all age groups, but training benefits were greater for people in late adolescence and adulthood than for people earlier in adolescence. Training did not increase performance on the face-perception task for any age group. Our findings suggest that for certain cognitive skills, training during late adolescence and adulthood yields greater improvement than training earlier in adolescence, which highlights the relevance of this late developmental stage for education. [ABSTRACT FROM AUTHOR]

Most arthroscopic rotator cuff repairs utilize suture passing devices placed through arthroscopic cannulas. These devices are limited by the size of the passing device where the suture is passed through the tendon. An alternative technique has been used in the senior author's practice for the past ten years, where sutures are placed through the rotator cuff tendon using percutaneous passing devices. This technique, dubbed the global percutaneous shuttling technique of rotator cuff repair, affords the placement of sutures from nearly any angle and location in the shoulder, and has the potential advantage of larger suture bites through the tendon edge. These advantages may increase the area of tendon available to compress to the rotator cuff footprint and improve tendon healing and outcomes. The aim of this study is to describe the global percutaneous shuttling (GPS) technique and report our results using this method. The GPS technique can be used for any full thickness rotator cuff tear and is particularly useful for massive cuff tears with poor tissue quality. We recently followed up 22 patients with an average follow up of 32 months to validate its usefulness. American Shoulder and Elbow Surgeons scores improved significantly from 37 preoperatively to 90 postoperatively (P<0.0001). This data supports the use of the GPS technique for arthroscopic rotator cuff repair. Further biomechanical studies are currently being performed to assess the improvements in tendon footprint area with this technique. [ABSTRACT FROM AUTHOR]

Enzymes, being remarkable catalysts, are capable of accepting a wide range of complex molecules as substrates and catalyze a variety of reactions with a high degree of chemo-, stereo- and regioselectivity in most of the reactions. Biocatalysis can be used in both simple and complex chemical transformations without the need for tedious protection and deprotection chemistry that is very common in traditional organic synthesis. This current review highlights the applicability of one class of biocatalysts viz.“lipases” in synthetic transformations, the resolution of pharmaceutically important small molecules including polyphenols, amides, nucleosides and their precursors, the development of macromolecular systems (and their applications as drug/gene carriers), flame retardants, polymeric antioxidants and nanocrystalline solar cells, etc. [ABSTRACT FROM AUTHOR]

Management of the unstable shoulder after a failed stabilization procedure can be difficult and challenging. Detailed understanding of the native shoulder anatomy, including its static and dynamic restraints, is necessary for determining the patient's primary pathology. In addition, evaluation of the patient's history, physical exam, and imaging is important for identifying the cause for failure after the initial procedure. Common mistakes include under-appreciation of bony defects, failure to recognize capsular laxity, technical errors, and missed associated pathology. Many potential treatment options exist for revision surgery, including open or arthroscopic Bankart repair, bony augmentation procedures, and management of Hill Sachs defects. The aim of this narrative review is to discuss in-depth the common risk factors for post-surgical failure, components for appropriate evaluation, and the different surgical options available for revision stabilization. Level of evidence Level V. [ABSTRACT FROM AUTHOR]

A simple, Rapid and Reproducible HPLC method has been developed for the estimation of Mesalamine in bulk drug and its Pharmaceutical dosage forms using RP C18 column. The mobile phase consists of Acetonitrile and water in the ratio of 60:40v/v and was pumped at a flow rate of 0.6ml/min at 25±1oc. The detection was carried out at 330nm and the calibration curve was linear in the range of 20-100μg/ml, Retention time was found to be 3.09min for run time of 5min. The method was statistically validated for its linearity, Precision and accuracy. Intra and Inter-day variation study was carried out and found to be less than 3% showing reasonable precision of the assay method. Parameters of validation obtained prove the accuracy of the method and its applicability for the determination of Mesalamine in tablet dosage formulations. [ABSTRACT FROM AUTHOR]

Background: Osteosarcomas are the most common solid malignant bone tumors, but little is known of their origin. The embryonal rest hypothesis views cancer cells as arising from committed progenitor stem cells in each tissue. Adult tissue contains primitive stem cells that retain the ability to differentiate across dermal lines, raising the possibility that the stem cell of origin of cancers may be from a more primitive stem cell than a progenitor.Questions/purposes: Can osteosarcoma cells, when cultured under conditions used for multipotent stem cells, be induced to differentiate into multiple phenotypes, including those of the three different dermal lineages: mesodermal, ectodermal, and endodermal?Methods: One rat and one human osteosarcoma cell line were cultured and treated with concentrations of 0, 10(-10), 10(-9), 10(-8), 10(-7), and 10(-6) mol/L dexamethasone for 5 weeks. Seventeen phenotypes were assayed either by tissue-specific histochemical stains or antibodies to tissue-specific proteins. Each phenotype was tested across all dexamethasone concentrations for each cell line and each phenotype was tested in three separate experiments with induction by dexamethasoneResults: Rat osteosarcoma (ROS) 17/2.8 and human osteosarcoma cell line U-2 show the appearance of cells that have markers for (1) mesodermal phenotypes such as bone, cartilage, skeletal muscle, and endothelial cells, (2) ectodermal phenotypes such as astrocytes, oligodendrocytes, neurons, and keratinocytes, and (3) an endodermal phenotype, hepatocytes. This indicates osteosarcomas are composed, at least in part, of primitive stem cells capable of differentiating into tissues from all three dermal lineages.Clinical Relevance: If osteosarcomas arise from primitive stem cells, then treatment of osteosarcomas with exogenous differentiation agents may cause the stem cells to differentiate, thus halting their proliferation and stopping tumor growth. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented referring to the complications faced in the surgery for peptic ulcer disease by surgeons.

Invasion is the hallmark of malignant tumors, and is responsible for the bad prognosis of the untreated cancer patients. The search for anti-invasive treatments led us to screen compounds of different classes for their effect in an assay for invasion. Thirty-nine new compounds synthesized in the present study along with 56 already reported compounds belonging mainly to the classes of lactones, pyrazoles, isoxazoles, coumarins, desoxybenzoins, aromatic ketones, chalcones, chromans, isoflavanones have been tested against organotypic confronting cultures of invasive human MCF-7/6 mammary carcinoma cells with embryonic chick heart fragments in vitro. Three of them (a pyrazole derivative, an isoxazolylcoumarin and a prenylated desoxybenzoin) inhibited invasion at concentrations as low as 1 μM; instead of occupying and replacing the heart tissue within 8 days, the MCF-7/6 cells grew around the heart fragments and left it intact, when treated with these compounds. At the anti-invasive concentration of 1 μM, the three compounds did not affect the growth of the MCF-7/6 cells, as shown in the sulforhodamine B assay. Aggregate formation on agar was not stimulated by any of the three anti-invasive compounds, making an effect on the E-cadherin/catenin complex improbable. This is an invasion suppressor that can be activated in MCF-7/6 cells by a number of other molecules. Our data indicate that some polyphenolic and heterocyclic compounds are anti-invasive without being cytotoxic for the cancer cells. [Copyright &y& Elsevier]

Eleven (±)-5/6/7-acetoxy-4-aryl-3,4-dihydrocoumarins have been synthesised in two steps starting from the coupling of cinnamic acid/substituted cinnamic acid with appropriate phenols, followed by acetylation in 50–83% overall yields. All hydroxy- and acetoxycoumarins were unambiguously identified on the basis of their spectral data. Candida antarctica lipase-catalysed deacetylation of these racemic acetoxydihydrocoumarins in dioxane occurred with moderate enantioselectivity. This is one of the rare examples of resolution using phenolic ester moiety as a remote handle for chiral recognition by a lipase. [Copyright &y& Elsevier]

The selectivity of Candida antarctica lipase has been demonstrated and employed in the manipulation of a diastereotopic furanose diol as the key step in the synthesis of a novel bicyclo 3-amino-3-deoxy furanose derivative, which is an important intermediate for the synthesis of bicyclic analogs of AZT. The asymmetrization of the diol has been achieved with preferred formation of a monoacylated product with 100% diastereoselectivity. An efficient synthesis of an intermediate in the synthesis of amino derivatized bicyclonucleosides is also described, two such novel compounds containing cycloamino residues have been prepared. [Copyright &y& Elsevier]

Poly(4-hydroxybenzyl alcohol) was synthesized enzymatically starting with 4-hydroxybenzyl alcohol using hydrogen peroxide as the oxidizing agent in methanol and 0.01 M phosphate buffer (pH 7.0) mixture (1:1, v/v) and at room temperature (25°C). Polymerization reaction was catalyzed by horseradish peroxidase (HRP). The polymer formed was characterized by UV-Vis, FT-IR, 1H and 13C-NMR spectroscopic studies, which revealed that HRP catalyzed polymer is composed of a mixture of phenylene and oxyphenylene units and alcoholic hydroxyl groups are not participating in the polymerization. The resulting poly(4-hydroxybenzyl alcohol) contains pendant primary hydroxyl groups which provide an opportunity to further functionalize the polymer. The post-functionalization of enzymatically synthesized polymers with photoresponsive chromophores provides new molecularly engineered materials that are useful in photonics and sensor applications. [ABSTRACT FROM AUTHOR]

Polyanilines (PANI) were synthesized from peroxidase-catalyzed polymerization of aniline with and without the presence of a template in the aqueous buffer solution of pH 4.3. The template used was poly(vinylphosphonic acid) (PVP). Solid-state 13C and 15N CP/MAS NMR techniques were applied to characterize the structure of polyaniline in its self-doped conducting, dedoped base, and redoped conducting form of PANI. The charge distribution along the polymer backbone in the protonated form of the polyaniline is also discussed. The structural features exhibited by a template assisted enzymatically synthesized PANI is the result of linear 1,4-coupling of aniline moiety while the PANI synthesized in the absence of template contains both 1,2- and 1,4-coupled products. Solid-state NMR studies on the enzymatically-synthesized polyaniline with the aid of template (PANI-PVP) confirmed the formation of a linear polymer chain containing alternate benzenoid-quinoid repeat units. The dedoped form is in the emeraldine base state of the polyaniline. The structural features in the spectra of the PANI synthesized without a template are quite different. Solid-state NMR data suggest that the PANI synthesized without aid of the template contains structures having C-C and C-N-C coupled products indicating the presence of branching in the polymer chain. [ABSTRACT FROM AUTHOR]

Actinomycosis of esophagus is uncommon. Herpes simplex virus, cytomegalovirus, candidiasis, tuberculosis, and other fungal infections are the commonly reported infections in both immunocompromised and immunocompetent patients. We report a case of esophageal actinomycosis in an end-stage renal disease patient. A 28-year-old lady, known case of systemic lupus erythematosus, hepatitis B virus infection with end-stage renal disease on regular maintenance hemodialysis since 5 years presented with history of epigastric pain and odynophagia for 1 week. Her upper gastrointestinal endoscopic examination revealed extensive necrotic areas with membrane in the esophagus. Histopathology revealed actinomycotic colonies and bacterial clumps. She was treated with intravenous penicillin followed by oral ampicillin for 6 months. She showed marked clinical improvement, and repeat endoscopy showed healing of ulceration and no evidence of actinomycosis. [ABSTRACT FROM AUTHOR]

Discusses the helical conformational specificity of enzymatically synthesized water-soluble conducting polyaniline nanocomposites. Synthesis of the chiral conducting polymer nanocomposites with the use of a biocatalytic route; Optoelectronic properties of the nanocomposites; Role of the enzyme HRP during polymerization.