Resonant transmission of light through surface plasmon structures

Plasmonics enables the realization of new optical components. Here, we report yet another plasmonic component based on a pair of surfaces displaying grating coupled plasmon enhanced transmission. We observe high quality factor transmission peaks as high as 100 through our plasmonic filter based on gratings obtained directly from optical storage disks. Wavelength and polarization dependent transmission is also demonstrated in the visible and infrared portions of the spectrum. The resonance wavelength of this filter can be tuned by simply changing the angle of incidence. Numerical calculations agree well with measurements. Our work can open up directions toward disposable optical components such as filters and polarizers. © 2009 American Institute of Physics

The Efficacy of Mesenchymal Stem Cell Transplantation in Caustic Esophagus Injury: An Experimental Study

Introduction. Ingestion of corrosive substances may lead to stricture formation in esophagus as a late complication. Full thickness injury seems to exterminate tissue stem cells of esophagus. Mesenchymal stem cells (MSCs) can differentiate into specific cell lineages and have the capacity of homing in sites of injury. Aim and Methods. We aimed to investigate the efficacy of MSC transplantation, on prevention of esophageal damage and stricture formation after caustic esophagus injury in rats. 54 rats were allocated into four groups; 4 rats were sacrificed for MSC production. Group 1, untreated controls (n: 10). Group 2, membrane labeled MSCs-treated rats (n: 20). Group 3, biodistribution of fluorodeoxyglucose labeled MSCs via positron emission tomography (PET) imaging (n: 10). Group 4, sham operated (n: 10). Standard caustic esophageal burns were created and MSCs were transplanted 24 hours after. All rats were sacrificed at the 21st days. Results. PET scan images revealed the homing behavior of MSCs to the injury site. The histopathology damage score was not significantly different from controls. However, we demonstrated Dil labeled epithelial and muscle cells which were originating from transplanted MSCs. Conclusion. MSC transplantation after caustic esophageal injury may be a helpful treatment modality; however, probably repeated infusions are needed

Phylogenetic, clinical, pathological and epidemiological characterization of feline coronavirus infections in cats, in Istanbul

IntroductionFeline coronavirus (FCoV) is a widespread viral infection affecting domestic and wild cats globally, with higher prevalence in young cats and multi-cat environments.MethodsIn this study, a total of 208 clinical samples (blood, fecal, ascitic fluid, pleural fluid, tissue) were collected between January 2018 and January 2020 from diseased cats. Clinical and demographic data were recorded, and hematobiochemical and molecular detection analyses were performed.ResultsA total of 189 blood samples (90.9%) were found seropositive for FCoV, while 79 fecal samples (38%) were found positive for FCoV RNA by real-time RT-qPCR. No significant association was found between FCoV-RNA positivity and age or gender, while a significant association was found with crossbreed cats (p < 0.05). Notable clinical signs included weight loss (47%), dullness (44%), respiratory distress (16%), vomiting (13%), ascites (13%), epileptic fits (13%), diarrhea (6%), and fever (5%). Fever, depression, diarrhea, and ascites were significantly more common in PCR-positive cats than in PCR-negative cats (p < 0.05). The relationship between FCoV-RNA positivity and hematobiochemical indices was variable. Elevated monocyte and neutrophil levels were observed in 51 and 29% of cases, respectively. Additionally, elevated ALT activity and bilirubinemia were detected in 19 and 28% of cats, respectively. Partial S gene nucleotide analysis showed a deletion of multiple nucleotides in all sequences obtained in the present study. Interestingly, these deletions were absent in all reference strains belonging to FCoV type 2. Among 68 FCoV strains, 42 formed a separate cluster with the reference strain (AY307020) during phylogenetic analysis. This cluster was further divided into several small sub-clusters. Several unique recombinant events and recombination signals were observed among partial S1 gene sequences. Notable histopathological findings included fibrinous serositis and pyogranulomatous inflammation in vital organs.DiscussionThis study provides comprehensive information on FCoV infections among cats in Turkey. The findings could significantly contribute to understanding the hematobiochemical manifestations, epidemiology, and risk factors associated with FCoV, ultimately aiding in the development of better prevention and treatment strategies. A continuous molecular surveillance program is required to understand the evolution and emergence of virulent strains of FCoV to design new antiviral therapies and vaccines

The Effect of Changes in Lower Incisor Inclination on Gingival Recession

Aim. Orthodontic treatment may promote development of recessions. The mechanism by which orthodontic treatment influences occurrence of recessions remains unclear. The aim of this study was to test the hypothesis that a change of mandibular incisor inclination promotes development of labial gingival recessions. Materials and Methods. The study sample comprised dental casts and lateral cephalograms obtained from 109 subjects before orthodontic treatment (Tb) and after orthodontic treatment (Ta). Depending on the change of lower incisor inclination during treatment, the subjects were divided into three groups: Retroclination (R), Stable Position (S), and Proclination (P). The presence of gingival recessions of mandibular incisors and clinical crown heights were assessed on plaster models. Results and Conclusions. From Tb to Ta, Inc_Incl showed a statistically significant change in the R, P, and S groups (p<0.05). Increase of clinical crown heights of the lower incisors (42, 4, and 31) was not statistically significant in any group. The only statistically significant intergroup difference was the greater increase of the clinical crown height of tooth number 32 in the P group in comparison with the R group (p=0.049). The change of lower incisor inclination during treatment did not lead to development of labial gingival recessions in the study sample