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Koel Chaudhury, Vishu Kumar, Jayaprakash Kandasamy, Sourav RoyChoudhurySchool of Medical Science and Technology, Indian Institute of Technology, Kharagpur, West Bengal, IndiaAbstract: Nanotechnology has considerably accelerated the growth of regenerative medicine in recent years. Application of nanotechnology in regenerative medicine has revolutionized the designing of grafts and scaffolds which has resulted in new grafts/scaffold systems having significantly enhanced cellular and tissue regenerative properties. Since the cell–cell and cell-matrix interaction in biological systems takes place at the nanoscale level, the application of nanotechnology gives an edge in modifying the cellular function and/or matrix function in a more desired way to mimic the native tissue/organ. In this review, we focus on the nanotechnology-based recent advances and trends in regenerative medicine and discussed under individual organ systems including bone, cartilage, nerve, skin, teeth, myocardium, liver and eye. Recent studies that are related to the design of various types of nanostructured scaffolds and incorporation of nanomaterials into the matrices are reported. We have also documented reports where these materials and matrices have been compared for their better biocompatibility and efficacy in supporting the damaged tissue. In addition to the recent developments, future directions and possible challenges in translating the findings from bench to bedside are outlined.Keywords: regenerative medicine, nanomedicine, nanotechnology

BACKGROUND/PURPOSE: The purpose of this prospective study was to review the operative findings, treatment strategies, as well as the results of management of 46 consecutive cases of jejunoileal and colonic atresia, managed over a 2-year period. MATERIALS AND METHODS: There were 42 patients with jejunoileal atresia (JIA) and 4 with colonic atresia (CA). The 4 group types were: type I-membranous (n=20), type II- blind ends separated by a fibrous cord (n=6), type IIIa- blind ends with a V-shaped mesenteric defect (n=10), type IIIb- apple-peel atresia (n=4) and type IV- multiple atresias (n=6). Primary surgery for JIA consisted of resection with a single anastomosis (n=37), anastomosis after tapering jejunoplasty (n=3), multiple anastomosis (n=1) and a Bishop-Koop ileostomy (n=1). For CA, resection with primary anastomosis was performed. A single end-to-oblique anastomosis after adequate resection of dilated proximal bowel, was the preferred surgical procedure. In the absence of facilities for administering TPN, early oral/nasogastric (NG) tube feeding was encouraged. In patients with anastomotic dysfunction, conservative treatment of the obstruction followed after its resolution by gradually increased NG feeds, was the preferred treatment protocol. RESULTS: Late presentation or diagnosis with hypovolemia, electrolyte imbalance, unconjugated hyperbilirubinemia (n=25) and sepsis (n=6), were significant preoperative findings. After resection and anastomosis, significant shortening of bowel length was seen in 16 patients (34.7%). Postoperative complications included an anastomotic leak (n=3), a perforation proximal to the anastomosis in 1 and anastomotic dysfunction in 5 patients. Full oral or NG tube feeding was possible only by the 13th to 31st postoperative day (POD), after the primary surgery in patients with anastomotic dysfunction and those undergoing reoperation. Overall, 38 patients survived (82.6%). Mortality was highest in patients with type IIIb or type IV JIA. CONCLUSIONS: Despite lack of ideal facilities for neonatal intensive care and administration of TPN, good results were achieved in the management of JIA and CA by following these principles: (1) adequate preoperative resuscitation, (2) meticulous surgical technique and a standardized surgical protocol, (3) early recognition of postoperative complications and their management by a uniform protocol and (4) wherever possible, early institution of oral or NG feeds, preferably by breast milk.

Accurate simulation of electronic excitations and deexcitations are critical for complementing complex spectroscopic experiments and can provide validation to theoretical approaches. Using a generalized framework, we contrast the accuracy and validity of orbital-constrained and linear-response approaches that build upon Kohn-Sham density functional theory (DFT) to simulate emission spectra of electronic origin and propose an efficient approximation, named many-body x-ray emission spectroscopy or MBXES, for simulating such processes. We show analytically as well as with computed examples that for electronic (de)excitation leading to an appreciable change in polarization (i.e., density rearrangement), the adiabatic approximation in a response-based formalism will be inadequate for the calculation of oscillator strength. Thus, such a change (e.g., in the net electrostatic dipole moment of a finite system) can be used as a metric for evaluating the applicability of the adiabatic response-based approach and can be particularly valuable in x-ray emission spectroscopy. On the other hand, MBXES, the flexible method introduced in this paper, can compute oscillator strengths accurately at a much lower computational expense on the basis of two DFT-based self-consistent field calculations. Using illustrative examples of emission spectra, the efficacy of the MBXES method is demonstrated by comparison with its parent theory, orbital-optimized DFT, and with experiments.

Background: Genetic instability of chromosome 11 is a frequent event in many solid tumours, including head and neck squamous cell carcinoma (HNSCC). Aims: To perform allelic imbalance analysis of cytogenetically [...]

A staged combustor concept for reducing pollutant emissions is currently under investigation. A numerical study was performed to investigate the chemically reactive flow with liquid spray injection for staged combustion. The staged combustor consists of an airblast atomizer fuel injector, a rich burn section, a converging connecting pipe, a quick mix zone, a diverging connecting pipe and a lean combustion zone. For computational efficiency, the combustor was split into two subsystems, i.e., the fuel nozzle/rich burn section and the quick mix/lean burn section. The current study investigates the effect of varying the mass flow rate split between the swirler passages for an equivalence ratio of 2.0 on fuel distribution, temperature distribution, and emissions for the fuel nozzle/rich burn section of a staged combustor. It is seen that optimizing these parameters can substantially improve combustor performance and reduce combustor emissions. The optimal mass flow rate split for reducing NOx emissions based on the numerical study was the same as found by experiment.