A study on optical and thermal properties of natural polymer-based hemicellulose compounds.

Films of husks of Plantango ovate, Cydonia oblonga, Mimosa pudica, Cochlospermum religiosum were prepared, delignified without protein and cellulose content, and their optical properties were evaluated. UV-Vis, FTIR TGA analysis revealed that these natural materials have strong potential in fiber optics, contact lenses and human transplantation infrastructure applications, where there is need of efficient transparency, high thermal stability and good conductivity with minimum light absorption. These natural polymeric films possess significant direct and indirect optical band gap values and better optical conductivity than currently in use synthetic polymeric materials. The Refractive index of these films is also found high in the visible region in comparison to pure or composite metal-doped synthetic films. Urbach energy (Eu), Dispersion energy (Ed), Average oscillation wavelength (λ0), and oscillation strength(S0) of this hemicellulose based natural polymeric films were found to be appropriate for such optical materials which are green, organic, economical and compatible to human systems.

A functional magnetic resonance imaging investigation of visual hallucinations in the human striate cortex.

PURPOSE: Human beings frequently experience fear, phobia, migraine and hallucinations, however, the cerebral mechanisms underpinning these conditions remain poorly understood. Towards this goal, in this work, we aim to correlate the human ocular perceptions with visual hallucinations, and map them to their cerebral origins. METHODS: An fMRI study was performed to examine the visual cortical areas including the striate, parastriate and peristriate cortex in the occipital lobe of the human brain. 24 healthy subjects were enrolled and four visual patterns including hallucination circle (HCC), hallucination fan (HCF), retinotopy circle (RTC) and retinotopy cross (RTX) were used towards registering their impact in the aforementioned visual related areas. One-way analysis of variance was used to evaluate the significance of difference between induced activations. Multinomial regression and and K-means were used to cluster activation patterns in visual areas of the brain. RESULTS: Significant activations were observed in the visual cortex as a result of stimulus presentation. The responses induced by visual stimuli were resolved to Brodmann areas 17, 18 and 19. Activation data clustered into independent and mutually exclusive clusters with HCC registering higher activations as compared to HCF, RTC and RTX. CONCLUSIONS: We conclude that small circular objects, in rotation, tend to leave greater hallucinating impressions in the visual region. The similarity between observed activation patterns and those reported in conditions such as epilepsy and visual hallucinations can help elucidate the cortical mechanisms underlying these conditions. Trial Registration 1121_GWJUNG.

Cervical lymph node metastases in squamous cell carcinoma of tongue and floor of mouth.

Oral squamous cell carcinoma has high chances of cervical lymph node metastasis. This case series describes the distribution of cervical lymph nodes in 50 cases of squamous cell carcinoma of tongue and floor of mouth. The mean age was 47.28±10.5 years. Thirty positive metastatic lymph nodes were found; 90% occurring at level I-II mostly in T4 size but also in T1 and T2 cases. The distribution of involved lymph nodes in oral cancer affects the neck dissection extent and is, therefore, an important pre-operative feature.

Reconstruction of mandibular defects with autogenous bone grafts: a review of 30 cases.

BACKGROUND: Multitudes of options are available for reconstruction of functional and cosmetic defects of the mandible, caused by various ailments. At the present time, autogenous bone grafting is the gold standard by which all other techniques of reconstruction of the mandible can be judged. The purpose of this study was to evaluate the outcome of different osseous reconstruction options using autogenous bone grafts for mandibular reconstruction. METHODS: This Interventional study was conducted at Department of Oral and Maxillofacial Surgery, King Edward Medical University/Mayo Hospital Lahore, from January 2008 to July 2009 including one year follow-up. The study was carried out on thirty patients having bony mandibular defects. They were reconstructed with the autogenous bone grafts from different graft donor sites. On post-operative visits they were evaluated for outcome variables. RESULTS: Success rate of autogenous bone grafts in this study was 90%. Only 10% of the cases showed poor results regarding infection, resorption and graft failure. CONCLUSION: Autogenous bone grafts, non-vascularised or vascularised, are a reliable treatment modality for the reconstruction of the bony mandibular defects with predictable functional and aesthetic outcome.