Stem Cell Therapeutics: Exploring Newer Alternatives to Human Embryonic Stem Cells

Stem cells therapeutics has come a long way since stem cells and their potential was discovered for the first time. Intense research into cellular biology of stem cells has revealed that they possess immense potential for curing many human diseases. Research done in last couple of decades revealed that a particular class of stem cells called, “Human embryonic stem cells (HESCs)” possessed exceptional self-renewal and pluripotency properties. There ability to differentiate into specialized cell lineages of all three embryonic germ layers contributed further towards their popularity. However, in recent times HESCs have come under the cross-hairs of critics, politicians and religious groups due to certain technical and ethical concerns related to them. Such problems with HESCs research have forced stem cell researchers to start exploring the prospects of using alternatives to HESCs for regenerative medicine and therapeutics. In the present review, various sources of stem cells have been described, which in near future, have the potential to replace HESCs in regenerative medicine

Bounds for Rankin--Selberg integrals and quantum unique ergodicity for powerful levels

Let f be a classical holomorphic newform of level q and even weight k. We show that the pushforward to the full level modular curve of the mass of f equidistributes as qk -> infinity. This generalizes known results in the case that q is squarefree. We obtain a power savings in the rate of equidistribution as q becomes sufficiently "powerful" (far away from being squarefree), and in particular in the "depth aspect" as q traverses the powers of a fixed prime. We compare the difficulty of such equidistribution problems to that of corresponding subconvexity problems by deriving explicit extensions of Watson's formula to certain triple product integrals involving forms of non-squarefree level. By a theorem of Ichino and a lemma of Michel--Venkatesh, this amounts to a detailed study of Rankin--Selberg integrals int|f|^2 E attached to newforms f of arbitrary level and Eisenstein series E of full level. We find that the local factors of such integrals participate in many amusing analogies with global L-functions. For instance, we observe that the mass equidistribution conjecture with a power savings in the depth aspect is equivalent to the union of a global subconvexity bound and what we call a "local subconvexity bound"; a consequence of our local calculations is what we call a "local Lindelof hypothesis".Comment: 43 pages; various minor corrections (many thanks to the referee) and improvements in clarity and exposition. To appear in JAM

Sporadic Medullary Microcarcinoma in a Young Patient - A Rare Case

Sporadic medullary microcarcinoma of thyroid is a rare disease detected usually in 0.15% of all thyroid malignancy. We report a case of sporadic medullary microcarcinoma (MMC) of thyroid in a 24 year old male presenting as solitary thyroid nodule. There was no family history of medullary carcinoma of thyroid. Although medullary carcinoma in a familial setting have been reported, sporadic MMC is rare especially in a young patient

Oscillating magnetoresistance due to fragile spin structure in metallic GdPd3_3

Studies on the phenomenon of magnetoresistance (MR) have produced intriguing and application-oriented outcomes for decades--colossal MR, giant MR and recently discovered extremely large MR of millions of percents in semimetals can be taken as examples. We report here the investigation of oscillating MR in a cubic intermetallic compound GdPd$_3$, which is the only compound that exhibits MR oscillations between positive and negative values. Our study shows that a very strong correlation between magnetic, electrical and magnetotransport properties is present in this compound. The magnetic structure in GdPd$_3$ is highly fragile since applied magnetic fields of moderate strength significantly alter the spin arrangement within the system--a behavior that manifests itself in the oscillating MR. Intriguing magnetotransport characteristics of GdPd$_3$ are appealing for field-sensitive device applications, especially if the MR oscillation could materialize at higher temperature by manipulating the magnetic interaction through perturbations caused by chemical substitutions.Comment: 10 pages, 7 figures. A slightly modified version is published in Scientific Report

DAMPs and PDT-mediated photo-oxidative stress: exploring the unknown

Damage-associated molecular patterns (DAMPs) or cell death associated molecular patterns (CDAMPs) are a subset of endogenous intracellular molecules that are normally hidden within living cells but become either passively released by primary and secondary necrotic cells or actively exposed and secreted by the dying cells. Once released, DAMPs are sensed by the innate immune system and act as activators of antigen-presenting cells (APCs) to stimulate innate and adaptive immunity. Cancer cells dying in response to a subset of conventional anticancer modalities exhibit a particular composition of DAMPs at their cell surface, which has been recently shown to be vital for the stimulation of the host immune system and the control of residual disease. Photodynamic therapy (PDT) for cancer has long been shown to be capable of killing malignant cells and concomitantly stimulate the host immune system, properties that are likely linked to its ability of inducing exposure/release of certain DAMPs. PDT, by evoking oxidative stress at specific subcellular sites through the light activation of organelle-associated photosensitizers, may be unique in incorporating tumour cells destruction and antitumor immune response in one therapeutic paradigm. Here we review the current knowledge about mechanisms and signalling cascades leading to the exposure of DAMPs at the cell surface or promoting their release, the cell death mechanism associated to these processes and its immunological consequences. We also discuss how certain PDT paradigms may yield therapies that optimally stimulate the immune system and lead to the discovery of new DAMPs