Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly. Wet AMD includes typical choroidal neovascularization (CNV) and polypoidal choroidal vasculopathy (PCV). The etiology and pathogenesis of CNV and PCV are not well understood. Genome-wide association studies have linked a multifunctional serine protease, HTRA1, to AMD. However, the precise role of HTRA1 in AMD remains elusive. By transgenically expressing human HTRA1 in mouse retinal pigment epithelium, we showed that increased HTRA1 induced cardinal features of PCV, including branching networks of choroidal vessels, polypoidal lesions, severe degeneration of the elastic laminae, and tunica media of choroidal vessels. In addition, HTRA1 mice displayed retinal pigment epithelium atrophy and photoreceptor degeneration. Senescent HTRA1 mice developed occult CNV, which likely resulted from the degradation of the elastic lamina of Bruch's membrane and up-regulation of VEGF. Our results indicate that increased HTRA1 is sufficient to cause PCV and is a significant risk factor for CNV.A dvanced age-related macular degeneration (AMD) can be classified into wet AMD and geographic atrophy (1, 2). Wet AMD includes the typical choroidal neovascularization (CNV) and polypoidal choroidal vasculopathy (PCV). CNV is caused by the growth of new blood vessels from the choroid into the subretinal pigment epithelium (RPE) and subretinal spaces, whereas PCV is caused by inner choroidal vessel abnormalities (3). PCV has two key features on indocyanine green angiography (ICGA): polypoidal vascular dilations and a network of branching abnormal choroid vessels (4). Both CNV and PCV can lead to recurrent serous exudation and hemorrhages (5). The etiology and pathogenesis of CNV and PCV are largely unknown.Numerous genetic association studies have shown that chromosome 10q26 is a major candidate region associated with the susceptibility of several types of AMD (6, 7), including PCV (8-10). The linkage peak was refined to two neighboring genes, HTRA1 (11, 12) and ARMS2 (or LOC387715) (13). HTRA1 is a multifunctional serine protease that is ubiquitously expressed in mammalian tissues (14, 15) but ARMS2 is primate-specific, with a proposed function in mitochondria (13, 16), extracellular matrix (17), or as a noncoding RNA (18). Variants in this region are in strong linkage disequilibrium (11-13, 16). There are three major competing hypotheses attributing increased risk of AMD to (i) increased HTRA1 (11, 12), (ii) decreased ARMS2 (16), or (iii) both increased HTRA1 and decreased ARMS2 (19). However, a series of studies on the influence of AMD-associated polymorphisms on the expression of ARMS2 and HTRA1 have yielded widely conflicting results (12,16,(18)(19)(20)(21)(22)(23)(24). As a result, the functional involvement of either HTRA1 or ARMS2 in AMD remains uncertain, despite strong genetic evidence (18,22). To clarify the role of HTRA1 in AMD pathogenesis, we transgenically expressed human HTRA1 in mouse RPE. We showed that increased HTRA1 is ...

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Exact solutions are obtained for a collective model of two identical two-level atoms interacting with a quantized bimodal field with intensity-dependent coupling terms in a lossless cavity. A unitary transformation method is used to solve the time-dependent problem that also gives the eigensolutions of the interaction Hamiltonian. The atomic population dynamics and the dynamics of the photon statistics of the two cavity modes are studied. We present evidence of cooperative effects.

In the present paper, the eigenfunctions and eigenvalues of the Hamiltonian of the interacting system have been obtained in two generalized Jaynes Cummings models separately, one in which the transition are mediated by two different modes of photon in the ladder configuration and the other involving two mode multi-photon interaction between the field and the atom. Effect of intensity dependent coupling between the field and the atom in both the above-mentioned cases have been investigated. Graphical features of the time dependence of population inversion have been analyzed when one of the field modes is prepared initially in a coherent state while the other one in a vacuum state.The unitary transformation method presented here for the special case of exact resonance not only solves the time-dependent problem but also provides the eigensolutions of the interacting Hamiltonian at the same time.Keywords Jaynes-Cummings (J-C) model · Rotating wave approximation (RWA) · Unitary operatorT · Two-mode ladder model · Two-mode k-photon interaction (2k interaction) ladder model · Intensity dependent coupling · Atomic population inversion W (t)

BackgroundAffordability, acceptability, accommodation, availability, and accessibility are the five most important dimensions of access to health services. Seventy two percent of the Indian population lives in semi-urban and rural areas. The strong mismatched ratio of hospitals to patients, rising costs of health care, rapidly changing demographics, increasing population, and heightened demands in pricing for technological health care usage in emerging economies necessitate a unique health delivery solution model using social media. A greater disease burden lies in the health care delivery in developing country like India. This is due to the lack of health care infrastructure in the majority of semi-urban and rural regions. New techniques need to be introduced in these regions to overcome these issues. In the present scenario, people use social media from business, automobiles, arts, book marking, cooking, entertainment, and general networking. Developed and advanced countries like the United States have developed their communication system for many years now. They have already established social media in a number of domains including health care. Similar practice incidences can be used to provide a new dimension to health care in the semi-urban regions of India.ObjectiveThis paper describes an extended study of a previous empirical study on the expectations of social media users for health care. The paper discusses what the users of social media expect from a health care social media site.MethodsMultiple regression analysis was used to determine the significance of the affect of four factors (privacy, immediacy, usability, and communication) on the usage of health care social media. Privacy, immediacy, usability, and communication were the independent variables and health care social media was the dependant variable.ResultsThere were 103 respondents who used the online questionnaire tool to generate their responses. The results from the multiple regression analysis using SPSS 20 showed that the model is acceptable, with P=.011, which is statistically significant on a P<.05 level. The observed F value (2.082) in ANOVA was less than the given value in the F table (2.61), which allowed us to accept the hypothesis that the independent variables influence the dependant variable. The users of social media in India expect that they can best utilize social media through emergency service information. They want to be able to learn the operations of the social media site quickly and expect to know about health camps and insurance collaborations. However, people like to become friends with people with similar interests based on their interests identified.ConclusionsHealth care social media requires intelligent implementation in developing economies. It needs to cater to the expectations of the users. The people in India, especially those in urban and semi-urban regions, are very interested in accepting the system.

Red Blood Cells (RBCs)-derived particles are an emerging group of novel drug delivery systems. The natural attributes of RBCs make them potential candidates for use as a drug carrier or nanoparticle camouflaging material as they are innately biocompatible. RBCs have been studied for multiple decades in drug delivery applications but their evolution in the clinical arena are considerably slower. They have been garnering attention for the unique capability of conserving their membrane proteins post fabrication that help them to stay non-immunogenic in the biological environment prolonging their circulation time and improving therapeutic efficiency. In this review, we discuss about the synthesis, significance, and various biomedical applications of the above-mentioned classes of engineered RBCs. This article is focused on the current state of clinical translation and the analysis of the hindrances associated with the transition from lab to clinic applications.

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A Gaussian laser beam propagating through collisional plasma heats the electrons non-uniformaly, creating a depressed density duct via ambipolar diffusion. As the beam propagates through the self-made duct its size shrinks due to self-focusing, and marginal rays begin to play a role. This effect is incorporated by expanding the eikonal up to fourth power in r. The radial intensity profile of the laser becomes less steep than Gaussian.