Surface modification of polydimethylsiloxane by the cataractous eye protein isolate.

Polydimethylsiloxane (PDMS), even though widely used in microfluidic applications, its hydrophobic nature restricts its utility in some cases. To address this, PDMS may be used in conjunction with a hydrophilic material. Herein, the PDMS surface is modified by plasma treatment followed by cross-linking with the cataractous eye protein isolate (CEPI). CEPI-PDMS composites are prepared at three pH and the effects of CEPI on the chemical, physical, and electrical properties of PDMS are extensively investigated. The cross-linking between PDMS and the protein are confirmed by FTIR, and the contact angle measurements indicate the improved hydrophilic nature of the composite films as compared to PDMS. Atomic Force Microscopy results demonstrate that the surface roughness is enhanced by the incorporation of the protein and is a function of the pH. The effective elastic modulus of the composites is improved by the incorporation of protein into the PDMS matrix. Measurements of the dielectric properties of these composites indicate that they behave as capacitors at lower frequency range while demonstrating resistive characteristics at higher frequency. These composites provide preliminary ideas in developing flexible devices for potential applications in diverse areas such as energy storage materials, and thermo-elective wireless switching devices.

Preliminary experience with diffuse correlation spectroscopy in acute ischemic stroke neurointerventional procedures.

BACKGROUND: Diffuse correlation spectroscopy (DCS) is a non-invasive optical technique that enables continuous blood flow measurements in various organs, including the brain. DCS quantitatively measures blood flow from temporal fluctuations in the intensity of diffusely reflected light caused by the dynamic scattering of light from moving red blood cells within the tissue. METHODS: We performed bilateral cerebral blood flow (CBF) measurements using a custom DCS device in patients undergoing neuroendovascular interventions for acute ischemic stroke. Experimental, clinical, and imaging data were collected in a prospective manner. RESULTS: The device was successfully applied in nine subjects. There were no safety concerns or interference with the standard angiography suite or intensive care unit workflow. Six cases were selected for final analysis and interpretation. DCS measurements with photon count rates greater than 30 KHz had sufficient signal-to-noise to resolve blood flow pulsatility. We found an association between angiographic changes in cerebral reperfusion (partial or complete reperfusion established in stroke thrombectomy cases; temporary flow arrest during carotid artery stenting) and those observed intraprocedurally with CBF measurements via DCS. Limitations of the current technology included sensitivity to the interrogated tissue volume under the probe and the effect of local changes in tissue optical properties on the accuracy of CBF estimates. CONCLUSION: Our initial experience with DCS in neurointerventional procedures showed the feasibility of this non-invasive approach in providing continuous measurement of regional CBF brain tissue properties.

Non-invasive low-cost deep tissue blood flow measurement with integrated Diffuse Speckle Contrast Spectroscopy.

Diffuse Correlation Spectroscopy (DCS) is a widely used non-invasive measurement technique to quantitatively measure deep tissue blood flow. Conventional implementations of DCS use expensive single photon counters as detecting elements and optical probes with bulky fiber optic cables. In recent years, newer approaches to blood flow measurement such as Diffuse Speckle Contrast Analysis (DSCA) and Speckle Contrast Optical Spectroscopy (SCOS), have adapted speckle contrast analysis methods to simplify deep tissue blood flow measurements using cameras and single photon counting avalanche detector arrays as detectors. Here, we introduce and demonstrate integrated Diffuse Speckle Contrast Spectroscopy (iDSCS), a novel optical sensor setup which leverages diffuse speckle contrast analysis for probe-level quantitative measurement of tissue blood flow. iDSCS uses a standard photodiode configured in photovoltaic mode to integrate photon intensity fluctuations over multiple integration durations using a custom electronic circuit, as opposed to the high frequency sampling of photon counts with DCS. We show that the iDSCS device is sensitive to deep-tissue blood flow measurements with experiments on a human forearm and compare the sensitivity and dynamic range of the device to a conventional DCS instrument. The iDSCS device features a low-cost, low-power, small form factor instrument design that will enable wireless probe-level measurements of deep tissue blood flow.

Peritraumatic distress in Southern Indian inhabitants during second wave COVID-19 pandemic: A community-level survey.

Introduction: As coronavirus disease 2019 (COVID-19) is a new disease which has ruining and dismantling the harmony of people internationally, its development and spread, creates turmoil, nervousness and dread among worldwide. Aim: To evaluate seriousness of peritraumatic problems among southern Indian inhabitants during the COVID-19 pandemic. Methodology: A referral sampling technique was continued until a sufficient sample size was reached, while this self-administered survey catches insights about depression, fears, psychological change, evasion cognitive change, and collectively quantifies the stress on a scale of 0-60. Expressive factual examinations were utilized to sum up clear cut information and inferential measurable investigations included Chi-square tests and Pearson's correlations were done. Results: The study included only those participants who understood English and had access to the internet. Inconsequential outcomes were found among gender in which both male and female members frequently showed apprehension and nervousness about COVID-19. 44.8% tried not to watch the news on COVID-19 as they were excessively frightened and make frenzy to family members. 90.9% of participants with lower education levels were more stressed over the thought of getting COVID-19 when showing manifestations related with the novel corona virus, which was statistically significant. Conclusion: The current assessment shows that almost all the study participants have felt restless, uncomfortable and terrified of watching the news whilst stressed over appearances related with COVID-19 due to their greater access to information.

Nanoencapsulation as a Promising Platform for the Delivery of the Morin-Cu(II) Complex: Antibacterial and Anticancer Potential.

Nanoencapsulation has emerged as a promising approach for the effective delivery of poorly aqueous soluble compounds. The current study focuses on the preparation of human serum albumin (HSA)-based nanoparticles (NPs) and poly lactic-co-glycolic acid (PLGA)-based nanoparticles for effective delivery of the morin-Cu(II) complex. The NPs were analyzed based on different parameters such as particle size, surface charge, morphology, encapsulation efficiency, and in vitro release properties. The average particle sizes were found to be 214 ± 6 nm for Mor-Cu-HSA-NPs and 185 ± 7.5 nm for Mor-Cu-PLGA-NPs. The release of the morin-Cu(II) complex from both the NPs (Mor-Cu-HSA-NPs and Mor-Cu-PLGA-NPs) followed a biphasic behavior, which comprises an early burst release followed by a sustained and controlled release. The resulting NPs also exhibit free radical scavenging activity confirmed by a standard antioxidant assay. The antibacterial activities of the NPs were investigated using a disk diffusion technique, and it was observed that both the NPs showed better antibacterial activity than morin and the morin-Cu(II) complex. The anticancer activities of the prepared NPs were examined on MDA-MB-468 breast cancer cell lines using a cytotoxicity assay, and the mode of cell death was visualized using fluorescence microscopy. Our results revealed that NPs kill the cancer cells with greater efficiency than free morin and the morin-Cu(II) complex. Thus, both HSA-based NPs and PLGA-based NPs can act as promising delivery systems for the morin-Cu(II) complex and can be utilized for further biomedical applications.

Comparison of functional activation responses from the auditory cortex derived using multi-distance frequency domain and continuous wave near-infrared spectroscopy.

Significance: Quantitative measurements of cerebral hemodynamic changes due to functional activation are widely accomplished with commercial continuous wave (CW-NIRS) instruments despite the availability of the more rigorous multi-distance frequency domain (FD-NIRS) approach. A direct comparison of the two approaches to functional near-infrared spectroscopy can help in the interpretation of optical data and guide implementations of diffuse optical instruments for measuring functional activation. Aim: We explore the differences between CW-NIRS and multi-distance FD-NIRS by comparing measurements of functional activation in the human auditory cortex. Approach: Functional activation of the human auditory cortex was measured using a commercial frequency domain near-infrared spectroscopy instrument for 70 dB sound pressure level broadband noise and pure tone (1000 Hz) stimuli. Changes in tissue oxygenation were calculated using the modified Beer-Lambert law (CW-NIRS approach) and the photon diffusion equation (FD-NIRS approach). Results: Changes in oxygenated hemoglobin measured with the multi-distance FD-NIRS approach were about twice as large as those measured with the CW-NIRS approach. A finite-element simulation of the functional activation problem was performed to demonstrate that tissue oxygenation changes measured with the CW-NIRS approach is more accurate than that with multi-distance FD-NIRS. Conclusions: Multi-distance FD-NIRS approaches tend to overestimate functional activation effects, in part due to partial volume effects.

Depression, suicidal ideation, and suicidal behaviors among dental students of Neo-state capital region in India.

BACKGROUND: The challenges of dental education place students at high risk of stress. Because dental education is a highly demanding and challenging course, placing heavy demands on the mental resources of the students, making them vulnerable to high levels of stress, this study aimed to determine the prevalence of depression, suicidal ideation, and suicidal behaviors in dental students. MATERIALS AND METHODS: A descriptive cross-sectional study was done on a convenience sample of 388 dental students in a teaching dental institution. Data were collected using standard, prevalidated, self-administered questionnaires (Patient Health Questionnaire-9 and Suicidal Behaviours Questionnaire-Revised [SBQ-R]). Analysis was done using SPSS version 20. Descriptive statistics, Chi-square test, and logistic regression were performed. RESULTS: At least half of the students were in major depression with different levels of severity. When students from different years were analyzed, majority from each year fell under II and III categories (P < 0.001). Most of the students reported that they do not have any suicidal ideation or behavior (SBQ-R). Nearly 16% of the students either presented the threat of suicidal attempt or likelihood of suicidal behavior in future. Almost 13% of the dental students thought of killing themselves in the past year for at least two times. Around 16% of them expressed to someone about their thought of committing suicide. CONCLUSION: Even though depression and suicidal tendencies were not prominent in dental students, there is a need to shed light on those who responded positively and take necessary reforms to relieve academic stress.

Oral healthcare-seeking behavior and perception of oral health and general healthcare among WHO indexed age groups in East-Coast India.

INTRODUCTION: In a country where 30,570 dentists graduate per year, it is staggering to acknowledge that only 10% of dentists serve the rural people, who constitute around 68.8% of the country's population. AIM: To find out the oral healthcare-seeking behavior, profile, and pattern in Tenali Mandal among WHO recommended index age groups. MATERIALS AND METHODS: A cross-sectional, multilocality, single-visit study was done to acknowledge the oral healthcare-seeking behavior, profile, and pattern in Tenali Mandal, Guntur, Andhra Pradesh. There are 9 villages, 2 peri-urban, and 1 town present in the Tenali Mandal and the study was conducted following the National Pathfinder Survey. RESULTS: Around 35.4% of the study participants utilized dental services while most of them sought care in the last 1-6 months (23.4%) and the main reason for the last dental visit was tooth pain (13.1%), followed by decayed tooth without pain (6.9%). Dental care-seeking behavior among the age group of 12 years was 1.611 times more when compared to 65-74 years age group which was statistically significant (P ≤ 0.010). For dental care-seeking behavior among gender, the males utilized 0.982 times less when compared to females which was not statistically significant (P ≤ 0.881), while for the place of residence, urban place was 2.707 times more utilizing the services when compared to rural place which was statistically significant (P ≤ 0.001). CONCLUSION: The results of the study indicates that the barriers of oral healthcare-seeking behavior among dental health conditions poses public health problems in the study area, as well as it is an important baseline indicator against which target for oral health improvement can be set and monitored.

Biodegradable protein films from gallic acid and the cataractous eye protein isolate.

Films have been prepared from the natural antioxidant gallic acid and a proteinaceous source, the discarded emulsion obtained after cataract surgery referred to as the cataractous eye protein isolate (CEPI). Fourier transform spectroscopy (FTIR) and SDS PAGE studies confirmed the crosslinking of gallic acid with CEPI. The cross-section and surface of films were further characterized by scanning electron microscopy (SEM). The decrease in crystallinity of the films was confirmed by X-ray diffraction studies. The thermal property of the films is enhanced by the addition of gallic acid as evidenced from the Thermogravimetric analysis (TGA) studies. Films having 2% (w/w) gallic acid exhibited the maximum tensile strength of 2.88 ±â€¯0.32 MPa comparable to other cross-linked films such as soy, casein, canola based protein films. The light barrier property of the films improved with incorporation of gallic acid. The cross-linked films were degraded by the application of the enzyme trypsin. The films also showed good antioxidant properties as determined from the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The gallic acid incorporated nontoxic CEPI films are biodegradable and possess appreciable mechanical properties and could find use in diverse applications including pharmaceuticals.

Tuning the mechanical and physicochemical properties of cross-linked protein films.

Films derived from natural sources such as proteins provide an advantage over synthetic films due to their noncytotoxicity, biodegradability, and vast functionality. A new protein source gained from the cataractous eye protein isolate (CEPI) obtained after surgery has been investigated for this purpose. Glycerol has been employed as the plasticizer and glutaraldehyde (GD) as a cross-linker. Fourier transform infrared spectroscopy was employed to characterize the films. Nanoindentation and thermogravimetric analyses reveal improved mechanical and thermal properties of the cross-linked films. The films with 20% (w/w) GD exhibited properties such as the highest modulus and low water solubility. It is possible to tune the properties based on the extent of cross-linking. All the films were completely degraded by the enzyme trypsin. The similarity of these films was checked by using the prepared films as a delivery vehicle for a model compound, ampicillin sodium. The encapsulation efficiency was found to be 74%, and in vitro release studies showed significant amounts of drug release at physiological pH. This study will help us understand how the properties of protein films can be tuned to obtain the desired physicochemical properties. These biodegradable protein films could find use in pharmaceutical industries as delivery carriers.

Flavonoid loaded nanoparticles as an effective measure to combat oxidative stress in Ribonuclease A.

Flavonoids like quercetin and myricetin serve as naturally occurring antioxidants but their bioactivity is limited due to low aqueous solubility and oxidation under physiological conditions. In this current study, the antioxidant activity of quercetin and myricetin loaded chitosan nanoparticles during the induced oxidation of Ribonuclease A (RNase A) has been compared with the corresponding free flavonoids. Oxidation of RNase A leads to intermolecular dityrosine (DT) bond formation which shows a characteristic fluorescence emission around 405 nm. Although both quercetin and myricetin loaded nanoparticles initially exhibit lower antioxidant property compared to the free flavonoids, however, with increase in oxidant concentration over time the DT fluorescence showed greater increase for free flavonoids in comparison to the nanoparticles. The polyphenol loaded nanoparticles are also found to be effective in preventing bacterial cell damage in oxidizing medium. The slow release of flavonoids from the nanoparticles is responsible for their prolonged antioxidant effect in the oxidizing medium unlike the free flavonoids which are exhausted almost completely in the initial phase.

Glycation of human γB-crystallin: A biophysical investigation.

Glycation of ocular lens proteins plays a vital role in the development of diabetic cataract. In order to investigate the role of glycation in cataractogenesis, the extent of glycation of human γB-crystallin was determined by an in vitro glycation study in a solution of high glucose content for upto 28days. The glycated protein has been purified and the formation of advanced glycation end products (AGEs) has been monitored spectroscopically. Size exclusion chromatographic studies showed that the covalent intermolecular crosslinking in the dimer formed was not due to disulfide bond formation. MALDI-TOF spectroscopy was employed to determine the number of glucose moieties attached to the protein due to glycation.

An insight into the interaction of phenanthridine dyes with polyriboadenylic acid: spectroscopic and thermodynamic approach.

Interaction of two phenanthridine dyes, namely ethidium bromide (EB) and propidium iodide (PI) with polyriboadenylic acid was investigated using various spectroscopic techniques. They were found to bind only with the single stranded form of the polymer, while no affinity was observed for the double stranded form. Enhanced binding observed for PI compared to EB may be attributed to the presence of external alkyl chain in PI. Thermodynamic studies showed negative enthalpy and negative entropy changes for the binding of both the dyes. Salt dependent studies revealed a lesser electrolytic contribution compared to the nonelectrolytic contribution to the total Gibbs free energy change in each case. This indicated importance of hydrophobic and van der Waal's interaction for the binding process. Overall, the binding data and detail energetics of interaction presented here would be helpful in the design of phenanthridine based molecules that interact with specific RNA structure.

Predicting herbicides concentrations in paddy water and runoff to the river basin.

This study was conducted to investigate the dissipation pattern and runoff of herbicides to the river basin from the paddy fields. Pesticide paddy field model (PADDY) was applied to predict herbicide concentration in paddy fields. A field study was conducted in a paddy farm of Higashi Hiroshima City, Hiroshima Prefecture, Japan in the year of 2003 paddy season. The herbicides were mefenacet, thiobencarb, and bensulfuron methyl. The sample water was analyzed by using gas chromatography and HPLC after solid phase extraction. Predicted dissipation rate of thiobencarb in paddy water was higher (DT50 = 4.36) than that measured, with a lower k value (-0.069). Two weeks after application no thiobencarb was detected in the drainage channel and down stream. In the down stream, thiobencarb was detected until 3 d after application, with a range of 0.02% to 0.08% of applied herbicide. The predicted dissipation rate (k) and half-life (DT50) of mefenacet was not significantly different from that of measured. In the drainage channel, upstream and downstream mefenacet was found during the whole study period. In downstream, the maximum concentration of mefenacet was present 0.61% of applied in the paddy field on 3DAH. The dissipation rate (k) of BSM varied from -0.0860 to -0.1059 to with half-life (DT50) 3.5 and 2.84 d. In upstream water, no BSM was detected except trace amounts (0.01 microg/L) at 3 d after application. However, in the drainage channel 8%, 6% and 1.58% of applied BSM was present at 0, 1 and 3 d after application respectively. In the down stream, the highest concentration was 1.06%, shortly after application.