6 research outputs found
In vitro anticariogenic effect of gallic acid against Streptococcus mutans
No full text445-451Involvement of Streptococcus mutans in the pathogenesis of dental caries among human populations is well established. Here, we studied the effect of gallic acid, a naturally occurring polyphenol on certain cariogenic activities of S. mutans. Gallic acid inhibited the glycosyltransferase activity, a key enzyme of sucrose metabolism by 27-36% in S. mutans. Minimal inhibitory concentration (MIC) of gallic acid (136 μg/mL) inhibited the growth of S.mutans by 50%. About 0.4 mM of the polyphenol reduced biofilm formation by 40%, hydrophobicity 60% and acid production 36% by the organism under in vitro growth conditions. Fluorescence microscopy revealed that in absence of gallic acid, the cells were present as clumps, however in the presence of gallic acid (68 µg/mL), they were well segregated due to the inhibition of biofilm formation. The present findings suggest that gallic acid has cariostatic activity against S. mutans, which may have potential application in prevention of dental caries
A comparative analysis of in-office vital 6% hydrogen peroxide activated charcoal tooth whitening treatment enhanced with an 810nm diode laser, compared to 35% hydrogen peroxide bleaching
No full textLaser dental bleaching is considered to be a contemporary approach to enhancing the in-office power bleaching procedure.
Objective
Investigate if laser enhanced 6% Hydrogen Peroxide (HP) solution is equivalent to 35% HP solution over a two-visit power bleaching treatment protocol. In a randomised double-blinded clinical trial, 43 patients were assigned to a group that received either the laser-enhanced 6% Hydrogen Peroxide (n=21) treatment, or the standard 35% Hydrogen Peroxide (n=22) treatment, over two visits, with a one-week interval. Activated charcoal HP paste was prepared for both groups. The laser enhanced 6% HP group received a dosage of 90 J/cm² per bleaching cycle using 810nm diode laser. Tooth colour was measured at the beginning and end of each session registering parameters L*, a* and b*, and tooth sensitivity. The calculated difference between these Parameters, ∆E, was the primary data focus. The mean ∆E over the treatment duration was used to answer the research question by a t-test to evaluate group differences at 5% significance level. The analysis revealed that the null hypothesis could not be rejected and the results were inconclusive. The observations expound the idea of an absorption enhancement mechanism, rather than a free radical activation, as the technique for improving bleaching outcomes
Rescue Thrombectomy for Early Hepatic Artery Thrombosis Using Stent Retriever in a Child Post Combined Deceased Donor Liver and Renal Transplant
No full textWe report this case of a 5-year-old child post combined liver and renal transplant for primary hyperoxaluria. Patient developed hepatic artery thrombosis on day 3 posttransplant that was managed by reexploration and reanastomosis of the hepatic artery. On day 4, the patient again developed hepatic artery thrombosis that failed to revascularize by surgical exploration and reanastomosis. Tissue plasminogen activator was injected into the hepatic artery intraoperatively to lyse any clot; however, no revascularization could be achieved. Subsequently, catheter angiogram confirmed no flow in the hepatic artery. A4 × 22 mm revive stent retriever was deployed across the site of occlusion and retrieved after 5 minutes of indwell time. Two such passes were made and complete recanalization of the hepatic artery was achieved. The hepatic artery remained patent as confirmed on serial Doppler images post intervention
Sparsity based Video Quality Assessment
No full textIn my research work, I developed a spatio-temporal objective quality algorithm to assess the perceptual
quality of natural videos in the Full-Reference (FR) as well as No-Reference (NR) settings. A common thread
running through a majority of Video Quality Assessment (VQA) algorithm is that spatio-temporal quality is
evaluated by pooling spatial and temporal quality that is measured independently. The proposed method is
holistic in the sense that we evaluate spatio-temporal quality using sparse spatio-temporal representations. In
other words, we do not pool independently measured spatial and temporal quality, but rather, jointly perform
the spatio-temporal quality assessment.
In this thesis, I present a novel Full-Reference (FR) video quality assessment (VQA) algorithm that op-
erates on the sparse representation coe
ffi
cients of local spatio-temporal (video) volumes. Proposed work is
motivated by the observation that the primary visual cortex of human visual system adopts a sparse coding
strategy to represent visual stimulus. We rely on the K-Singular Value Decomposition (K-SVD) algorithm
to construct spatio-temporal dictionaries for sparsely representing local spatio-temporal volumes of natural
videos. Then show that the sparse representation coe
ffi
cients of these local volumes possess excellent dis-
tortion discrimination properties. A family of dictionaries that span a wide range of spatio-temporal scales
is constructed. The distance between the sparse coe
ffi
cients of the reference and distorted videos over the
family of dictionaries serves as the feature representing perceptual quality. Support Vector Regression (SVR)
is used to learn the relation between this feature and Di
ff
erence Mean Opinion Score (DMOS). The proposed
algorithm delivers competitive performance over the LIVE standard definition (SD), EPFL standard definition
(SD) and the LIVE Mobile high definition (HD) databases.
Furthur, I also propose No-Reference (NR) video quality assessment (VQA) algorithm that operates on
the sparse representation coe
ffi
cients of local spatio-temporal volumes. Empirically demonstrate that the his-
togram of the sparse representations corresponding to each atom in the dictionary can be modelled well using
a Generalised Gaussian Distribution (GGD). Then show that the GGD model parameters are good features
for distortion estimation. The GGD model parameters corresponding to each atom of the dictionary form the
feature vector that is used to predict quality using Support Vector Regression (SVR). The proposed algorithm
delivers competitive performance over the LIVE SD, EPFL SD, LIVE HD and CSIQ video databases.
The proposed FR-VQA and NR-VQA algorithms are simple and computationally e
ffi
cient as compared
to other state-of-the-art FR-VQA as well as NR-VQA algorithms
Exploring ‘The House At Pooh Corner’ trough Stylistics and New Criticism Analysis
No full textThis project employs a Stylistic and New Criticism analysis in order to better understand the last chapter of A. A. Milne’s The House At Pooh Corner. Aspects of Child Orientated Criticism are also used to further the discussion of the findings. The combination of the two methods of analysis allowed for the examination of the style of language that is used as well as the themes and plot line presented in the text. Through textual analysis it can be determined, that the two approaches used in the text complete rather than contradict each other in the overall meaning-making process, as they do not differ in their chief preferences in general. Furthermore the use of Stylistics showed that Milne’s employs language in a way that makes the text favourable to be read out loud to children by adults. While New Criticism allowed for navigation of the various complexities found in the text. Lastly Child Orientated Criticism shows that the text can act as a shared place of Childness for both adults and children.This project employs a Stylistic and New Criticism analysis in order to better understand the last chapter of A. A. Milne’s The House At Pooh Corner. Aspects of Child Orientated Criticism are also used to further the discussion of the findings. The combination of the two methods of analysis allowed for the examination of the style of language that is used as well as the themes and plot line presented in the text. Through textual analysis it can be determined, that the two approaches used in the text complete rather than contradict each other in the overall meaning-making process, as they do not differ in their chief preferences in general. Furthermore the use of Stylistics showed that Milne’s employs language in a way that makes the text favourable to be read out loud to children by adults. While New Criticism allowed for navigation of the various complexities found in the text. Lastly Child Orientated Criticism shows that the text can act as a shared place of Childness for both adults and children
Appropriateness of antibiotic prescribing for urinary tract infection in the emergency department of a tertiary care hospital
No full textBackground: Urinary tract infections (UTIs) are frequently diagnosed in the Emergency Departments (EDs) in Saudi Arabia. Despite their prevalence, there is a lack of localized data on antibiotic prescribing practices for UTIs in EDs, hampering optimal patient care and antibiotic resistance management. Objective: This study aimed to evaluate the appropriateness of antibiotic prescriptions for UTI patients by examining adherence to treatment guidelines at a tertiary care ED in Saudi Arabia. Methods: A retrospective cohort analysis was performed in UTI patients with ≥18 years of age who were presented to the ED at a tertiary care hospital between January 2022 and January 2023. 179 patients were randomly selected for enrollment, and data related to their demographics, medical history, microbial isolation, administered antibiotics, and incidence of recurrent infections were collected. Results: Ciprofloxacin (38 %), Cefuroxime (26.8 %), and Nitrofurantoin (16.8 %) were the most prescribed antibiotics. The female population accounted for 87.3 % of UTI cases. Notably, 40.7 % lacked microbial growth or data. Inappropriateness was found in 55.3 % of selection, 27.9 % of dosing, and 38.5 % of treatment duration confined to antibiotics in UTI management. Moreover, complicated UTIs rather than duration and indication for antibiotic therapy were independent risk factors for the re-occurrence of UTIs. Conclusions: The study depicted an overall 44.7 % of appropriate antibiotic prescriptions in UTI patients. However, it also highlighted the necessity for tailored interventions and promotional efforts aimed at promoting the rational use of antibiotics in patients, thereby preventing resistance and treatment failure
