Fast by nature - how stress patterns define human experience and performance in dexterous tasks.

In the present study we quantify stress by measuring transient perspiratory responses on the perinasal area through thermal imaging. These responses prove to be sympathetically driven and hence, a likely indicator of stress processes in the brain. Armed with the unobtrusive measurement methodology we developed, we were able to monitor stress responses in the context of surgical training, the quintessence of human dexterity. We show that in dexterous tasking under critical conditions, novices attempt to perform a task's step equally fast with experienced individuals. We further show that while fast behavior in experienced individuals is afforded by skill, fast behavior in novices is likely instigated by high stress levels, at the expense of accuracy. Humans avoid adjusting speed to skill and rather grow their skill to a predetermined speed level, likely defined by neurophysiological latency.

Spatiotemporal reconstruction of the breathing function.

Breathing waveform extracted via nasal thermistor is the most common method to study respiratory function in sleep studies. In essence, this is a temporal waveform of mean temperatures in the nostril region that at every time step collapses two-dimensional data into a single point. Hence, spatial heat distribution in the nostrils is lost along with valuable functional and anatomical cues. This article presents the construction and experimental validation of a spatiotemporal profile for the breathing function via thermal imaging of the nostrils. The method models nasal airflow advection by using a front-propagating level set algorithm with optimal parameter selection. It is the first time that the full two-dimensional advantage of thermal imaging is brought to the fore in breathing computation. This new multi-dimensional measure is likely to bring diagnostic value in sleep studies and beyond.

Design and Development of Thermoreversible Ophthalmic In Situ Hydrogel of Moxifloxacin HCl.

Conventional eye drops show relatively low bioavailability due to poor precorneal contact time. In situ hydrogels are of great importance in providing sustained ocular drug delivery. By exhibiting elastic properties they resist ocular drainage of the drug leading to longer contact times. In the present study an in situ gelling thermoreversible mucoadhesive gel was formulated of an antibacterial agent, Moxifloxacin HCl using a combination of poloxamer 407 and poloxamer 188 with different mucoadhesive polymers such as Xanthan gum and Sodium alginate with a view to increase gel strength and bioadhesion force and thereby increased precorneal contact time and bioavailability of the drug. Formulations were evaluated for physical parameters like clarity, pH, spreadability, drug content, gelation temperature, gel strength, bioadhesion force and in vitro drug release study. Formulations were found transparent, uniform in consistency and had good spreadability within a pH range of 6.8 to 7.4. A satisfactory bioadhesion (3298 to 4130 Dyne/cm2) on the sheeps corneal surface and good gel strength (95 to 128 sec) was also observed. As the concentration of mucoadhesive polymers in the gel formulation increased, the rate of drug release decreased. The order of drug release was in order: Xanthan gum > Sodium alginate. It was concluded that a thermoreversible in situ gel of Moxifloxacin HCl can be formulated by combining with mucoadhesive polymers and used effectively as safe and sustained ocular drug delivery. This combination provided greater bioadhesion force and gel strength as compared to the thermoreversible polymers i.e., poloxamer 407 (PF 127) or 188 (PF 68) when used alone.

Studies on Poloxamer Based Mucoadhesive Insitu Ophthalmic Hydrogel of Moxifloxacin HCL.

Conventional eye drops shows relatively low bioavailability due to poor precorneal contact time. In situ hydrogels are of great importance in providing sustained ocular drug delivery due to their elastic properties hydrogels resist ocular drainage leading to longer contact times. In the present study an in situ gelling thermoreversible mucoadhesive gel was formulated of an antibacterial agent Moxifloxacin HCl using combination of poloxamer 407 and poloxamer 188 with different mucoadhesive polymers such as Xanthan gum and Sodium alginate with a view to increase in gel strength and bioadhesion force and thereby increase in precorneal contact time and there by increase in bioavailability of the drug. The formulations were evaluated for physical parameters like Clarity, pH, spreadability, drug content, gelation temperature, gel strength, bioadhesion force and in vitro drug release study. The formulated gels were transparent, uniform in consistency and had spreadability with a pH range of 6.8 to 7.4. A satisfactory bioadhesion (3298 to 4130 Dyne/cm(2)) on the sheep's corneal surface and good gel strength (95 to 128 sec) were also observed. As the concentration of mucoadhesive polymers in the gel formulation increases, the rate of drug release decreases. The order of drug release was Xanthan gum>Sodium alginate. It was concluded that a thermoreversible in situ gel formulation with Moxifloxacin HCl can be formulated by combining with mucoadhesive polymers and can effectively be used in safe and sustained ocular drug delivery with greater bioadhesion force and gel strength as compared to the thermoreversible polymers poloxamer 407 or 188 when used alone.

Modulation of lead toxicity by Spirulina fusiformis.

The modulatory effects of lead toxicity by Spirulina fusiformis (Oscillatoreaceae) were observed on the testes of Swiss albino mice at a dose of 800 mg/kg body weight. The Spirulina fusiformis was non-toxic at the dose given. A significant enhancement in the survival time was observed in the pre- and post-treated Spirulina group compared with the control (lead treated) group. Lead induced toxicity was also reduced in terms of testes weight, animal weight, tubular diameter in the pre Spirulina treated group. The modulatory effects of Spirulina may be attributed to the presence of the antioxidants, beta-carotene and SOD enzyme.

The biological approach to the radiotherapy of the oral cancers of South India.

Two-thirds of all cancers in South India are squamous cell carcinomas, of which 78% to 93% are late cases requiring radiotherapy. Oral cancers, which constitute the majority of these, provided an excellent clinical model for studies in radiotherapeutic biology. Their characteristics made them ideally suited for our clinical trials. The paper reviews the special biology of these lesions, the factors involved in their radiation non-response, the therapeutic postulations that suggested themselves, the implementation of these therapeutic protocols and the mixed story of failure and success that has marked the two decades of these studies. It discovers the fact that radiation response is not just a factor of tumor extent but involves several biological subtleties in both tumor and its host environment. It also discusses possible future approaches to bridge a gap of about 30% failure in these lesions, especially in the context of a poor economy.