23 research outputs found

    Polymeric peptide pigments with sequence-encoded properties

    Get PDF
    Melanins are a family of heterogeneous polymeric pigments that provide ultraviolet (UV) light protection, structural support, coloration, and free radical scavenging. Formed by oxidative oligomerization of catecholic small molecules, the physical properties of melanins are influenced by covalent and noncovalent disorder. We report the use of tyrosine-containing tripeptides as tunable precursors for polymeric pigments. In these structures, phenols are presented in a (supra-)molecular context dictated by the positions of the amino acids in the peptide sequence. Oxidative polymerization can be tuned in a sequence-dependent manner, resulting in peptide sequence–encoded properties such as UV absorbance, morphology, coloration, and electrochemical properties over a considerable range. Short peptides have low barriers to application and can be easily scaled, suggesting near-term applications in cosmetics and biomedicine

    Periodontal infections and cardiovascular disease: Is it a mere association?

    Get PDF
    Abstract The oral cavity is a major site of chronic infection and inflammation, particularly periodontal or chronic gum diseases

    Polymeric peptide pigments with sequence-encoded properties

    Get PDF
    Melanins are a family of heterogeneous polymeric pigments that provide ultraviolet (UV) light protection, structural support, coloration, and free radical scavenging. Formed by oxidative oligomerization of catecholic small molecules, the physical properties of melanins are influenced by covalent and noncovalent disorder. We report the use of tyrosine-containing tripeptides as tunable precursors for polymeric pigments. In these structures, phenols are presented in a (supra-)molecular context dictated by the positions of the amino acids in the peptide sequence. Oxidative polymerization can be tuned in a sequence-dependent manner, resulting in peptide sequence–encoded properties such as UV absorbance, morphology, coloration, and electrochemical properties over a considerable range. Short peptides have low barriers to application and can be easily scaled, suggesting near-term applications in cosmetics and biomedicine

    Adjunctive Orthodontic Treatment with Lingual Orthodontic System

    Full text link
    The lingual orthodontic therapy though started in 1972, could not be popular till the beginning of 1990. In Nepal it does not have a history of more than a year. It is started in Dhulikhel Hospital for the first time in Nepal. Usually orthodontic therapy is meant for putting braces on the labial surface of the teeth which is called labial orthodontic system. Lingual orthodontic system is a purely invisible kind of orthodontic therapy in which braces are placed behind the teeth. The advantages of lingual orthodontic therapy are: invisibility, better biomechanics and improved patient compliance. On the other hand it is difficult to master and costlier than labial orthodontics. We have presented six adjunctive orthodontic cases treated by lingual system with the same end result comparable to labial orthodontic system. DOI: http://dx.doi.org/10.3126/kumj.v9i4.6351 Kathmandu Univ Med J 2011;9(4):306-9</jats:p

    Prevalence of palate-gingival groove in patients of Dhulikhel Hospital

    No full text
    Background: Palato-gingival groove is a rare developmental anomaly leading to pulpal and periodontal diseases. Radicular extensions of these grooves are areas for plaque accumulation which are difficult to clean. Its clinical and radiographic findings mimic endo-perio lesions leading to diagnostic dilemma, ineffective treatment attempts and treatment failures. Objectives: To investigate the prevalence of coronal and radicular palato-gingival groove in dental patients visiting Dhulikhel Hospital and its association with gingival disease. Methods: Patients (N=231) visiting dental out-patient department of Dhulikhel Hospital, were examined for the presence or absence of palato-gingival groove in maxillary anteriors. Loe and Silness Gingival index was also recorded for all the patients using University of North Caroline-15 periodontal probe. Chisquare test was used to test the association of the presence of palato-gingival groove and gingival disease. P value of &lt;0.05 was considered to be significant. Results: A total of 1362 maxillary anterior teeth were included in the study. The prevalence of coronal palatogingival groove among 1362 teeth was 6.6%. Coronal palato-gingival grooves were more common in females (56.6%) than in male (43.3%) patients. Prevalence of radicular groove was only 0.88% for lateral incisors and 0.2% for canines. There was no significant association between palate-gingival groove and gingival disease (P=0.91). Conclusion: The prevalence of palato-gingival groove is common in dental patients visiting Dhulikhel Hospital. Gingival disease is not significantly associated with palate-gingival groove. DOI: http://dx.doi.org/10.3126/jcmsn.v10i1.12765 Journal of College of Medical Sciences-Nepal, 2014, Vol.10(1); 32-36</p

    Tooth -A Potential Graft Material for Periodontal Regeneration?

    Full text link
    Use of tooth as a promising replacement substitute has been validated by various animal as well as human studies. Though widely used in GBR and Sinus grafting techniques, its use in periodontal intrabony defect is not documented. In the present case report, the tooth graft has been placed in periodontal intrabony defect. Post-operative CBCT after 26 weeks revealed homogeneous incorporation of tooth graft. Clinical parameters show bone fill. However; results with larger sample size could further validate the use of tooth graft in periodontal regeneration.</jats:p

    Slope stability analysis along the proposed Kathmandu-Hetauda Road with tunnel sections

    Full text link
    The proposed Kathmandu-Hetauda Road alignment passes through Thankot, Chitlang, Kulekhani, Bhimphedi, and Bhaisedobhan. It is the shortest as well as least hazardous route very suitable for a standard highway. It has the following three tunnel sections: the Thankot Tunnel (3.2 km long), the Kulekhani Tunnel (500 m long), and the Chisapani Tunnel (3.8 km long). The alignment passes through the Kathmandu Nappe, Upper Nawakot Group of the Lesser Himalaya, and the Siwaliks. It also crosses the Main Boundary Thrust and the Mahabharat Thrust, four major faults/shear zones, and a major fold axis.&#x0D; The areas of plane sliding, wedge sliding, and toppling are delimited on the basis of the study of discontinuities along the proposed alignment. The stability analysis show s that 60-75% of the total road length is stable, 20-30% is fair, 5- 15% is weak, and 2-5% is critical.</jats:p

    Deformation structures in central Nepal and their engineering geological significance

    Full text link
    Geological maps of the Helambu-Kathmandu area and Kathmandu-Hetauda area with their suitable cross-sections are presented. On the basis of the deformation history, the deformation structures recorded from the field study as well as from the air photo interpretations are classified as continuous and discontinuous deformation structures. All types of discontinuous deformation structures are considered as discontinuities. Discontinuities play decisive role in engineering geology breaking the continuity of the mechanical behaviour of the rockmass at different scales. On the basis of spacing, width, mineral fill and extent, the discontinuities are classified into seven orders. Such classification is essential and appropriate for rockmasses, which are heavily affected by intense tectonic deformation in the Himalaya, the Alps or corresponding orogens. The study area within central Nepal is having many engineering geological problems. Stability of the rock slopes and underground excavations are two major engineering geological problems to deal here with. Significance of the different order of discontinuities in the light of these engineering geological problems are discussed. Orientation of different order of discontinuities is an important parameter affecting blasting, span width, roof support and ground water flow and related problems in the proposed tunnels in the study area. Such structures are also important factor for the stability of the natural slopes and cut slopes.</jats:p
    corecore