Search

Aim: To see whether prophylactic central compartment dissection is recommended for advanced papillary thyroid cancer or as part of selective neck node dissection. Central compartment dissection is a technically demanding surgical procedure and carries a higher incidence of complications. The present retrospective case-control study analysed the impact of prophylactic central compartment dissection on the long-term outcome of advanced (N0-T3/T4) papillary thyroid cancer. Materials and methods: Case records of patients operated on for papillary thyroid cancer from 2005 to 2010 were reviewed and patients with Tumour stage 3–4 and N0 nodal status were included in the study. The institutional protocol was to perform total thyroidectomy with central compartment dissection during the early phase of the study period (2005 to 2008) but this strategy was shifted to total thyroidectomy alone during the latter phase. Fifty-five patients were included in the study and 29 of the cohort had total thyroidectomy with prophylactic central compartment dissection as the primary surgery and the remaining 26 had a total thyroidectomy as the primary surgical procedure. Result: Patients were followed up for a median duration of 115 months and found to have no significant difference in the incidences of loco-regional recurrences between the groups. (n:4 (14%) Vs n: 3 (12%) p =.463). The disease-free survival and overall survival were not significantly different in the groups. There was a trend to an increase in the incidence of permanent hypoparathyroidism in patients who had central compartment dissection. Conclusion: Prophylactic central compartment dissection did not influence the 10-year outcome of advanced node-negative papillary thyroid cancers. [ABSTRACT FROM AUTHOR]

An experiment was conducted under the ICAR-All India Coordinated Research Project on Fruits to study the high density planting (HDP) and nutrient requirement of banana at six research centres across the country, including Bhubaneswar (Orissa), Gandevi (Gujarat), Jalgaon (Maharashtra), Jorhat (Assam), Kannara (Kerala) and Mohanpur (West Bengal) to enable higher productivity of banana and profit to farmers. Objective of this study was to explore the possibility of increasing productivity through intervention of only per unit plant population (through planting system) and level of nutrition, but without any interference to the regional choices of variety (e.g. choice variety Nendran for Kerala or Martaman for West Bengal), production system (mono/poly- clone, single/multi-year plantation, and POP of respective states), for which national productivity ranges are much skewed also. Results indicated that intervention of only plant density could increase productivity of banana within the existing system of production and choice of variety of different region or states. The experiment was laid out in RBD with four planting densities (S1P2, S1P3, S2P2and S2P3, where S1=2m x3m, S2=1.8m x3.6m, P2=2 suckers/hill, P3=3 suckers/hill), three nutrition levels (F1, F2and F3, which is 100%, 75% and 50% of RDF) and one with region-specific conventional planting density and nutrition (100% of RDF) practices as control. The results of this experiment showed that HDP (S1P3, 5000 plants / ha) in banana, accommodating three suckers per hill at 2m x 3m spacing increased productivity over the conventional system at the Bhubaneswar, Gandevi, Jorhat, Kannara and Mohanpur centres. The increase in productivity due to HDP (5,000/ha) over control was 28.9% (RDF 25%) to 50.6% (RDF 100%) at Bhubaneswar, 15.2% (RDF 25%) to 21.9% (RDF 100%) at Gandevi, 4.0% (RDF 25%) to 7.4% (RDF 100%) at Jorhat, 33.5%(RDF 25%) to 43.5% (RDF 100%) at Kannara and 46.5%(RDF 25%) to 79.0% (RDF 100%) at Mohanpur. The nutrient requirement under HDP was 100% RDF at Kannara, 75% RDF at Bhubaneswar and Mohanpur and 50% RDF at Gandevi and Jorhat centres, which indicates a saving in cost of fertilizer input by 25% -50%. It is therefore, recommended for HDP (5000 plants/ha) in banana, accommodating three suckers per hill at 2m x 3m (6.6 ft x 3.8 ft) spacing with 50% RDF in the agro-climatic regions of Gandevi and Jorhat, with 75% RDF in the agro-climatic regions of Bhubaneswar and Mohanpur and with 100% RDF in the agro-climatic region of Kannara in order to ensure higher productivity and profit to farmers. [ABSTRACT FROM AUTHOR]

Human Dual-specificity tyrosine (Y) Regulated Kinase 1A (DYRK1A) is encoded by a dosage dependent gene whereby either trisomy or haploinsufficiency result in developmental abnormalities. However, the function and regulation of this important protein kinase are not fully understood. Here, we report proteomic analysis of DYRK1A in human cells that revealed a novel role of DYRK1A in DNA double-strand breaks (DSBs) repair, mediated in part by its interaction with the ubiquitin-binding protein RNF169 that accumulates at the DSB sites and promotes homologous recombination repair (HRR) by displacing 53BP1, a key mediator of non-homologous end joining (NHEJ). We found that overexpression of active, but not the kinase inactive DYRK1A in U-2 OS cells inhibits accumulation of 53BP1 at the DSB sites in the RNF169-dependent manner. DYRK1A phosphorylates RNF169 at two sites that influence its ability to displace 53BP1 from the DSBs. Although DYRK1A is not required for the recruitment of RNF169 to the DSB sites and 53BP1 displacement, inhibition of DYRK1A or mutation of the DYRK1A phosphorylation sites in RNF169 decreases its ability to block accumulation of 53BP1 at the DSB sites. Interestingly, CRISPR-Cas9 knockout of DYRK1A in human and mouse cells also diminished the 53BP1 DSB recruitment in a manner that did not require RNF169, suggesting that dosage of DYRK1A can influence the DNA repair processes through both RNF169-dependent and independent mechanisms. Human U-2 OS cells devoid of DYRK1A display an increased HRR efficiency and resistance to DNA damage, therefore our findings implicate DYRK1A in the DNA repair processes. [ABSTRACT FROM AUTHOR]

Objective: Polyhydramnios places increased tension on the fetal membranes and should conceptually be associated with an increased need for tissue remodeling to prevent premature rupture of membranes (PROM). Herein we use polyhydramnios as a model to study the association of the collagenase class of matrix metalloproteinases (MMPs) with tissue remodeling during pregnancy. Methods: Amniotic fluids were collected by transabdominal amniocentesis from women with polyhydramnios and from women with normal amniotic fluid volume at second trimester, third trimester and at term. Fluids were assayed for MMP-1 and MMP-13 (collagenase-1 and 3) using ELISA. The concentrations in polyhydramnios were compared with subjects undergoing amniocentesis with normal amniotic fluid volume. Statistical comparisons were made using Scheffes method for correction in multiple means comparison. P of -0.05 was considered statistically significant. Results: MMP-1 and MMP-13 are present in the amniotic fluid at all stages of pregnancy. The concentrations of these MMPs were significantly elevated in the polyhydramnios samples independent of gestational age. Conclusion: Polyhydramnios is associated with increased amniotic fluid concentrations of MMP-1 and MMP-13 suggesting their role in tissue remodeling. [ABSTRACT FROM AUTHOR]

We report on the analysis of temperature-dependent current–voltage characteristics and impedance measurements of electrochemically doped poly(3-methylthiophene) devices at different doping levels. The extent of doping is carefully tailored such that only the bulk-limited transport mechanism prevails. A transition from exponentially distributed trap-limited transport to trap-free space-charge-limited current is observed in current–voltage conduction upon increasing the doping. The obtained trap densities (3.2  ×  1016 cm−3 and 8.6  ×  1015 cm−3) and trap energies (31.7 meV and 16.6 meV) for different devices signify the variation in disorder with doping, which is later supported by impedance measurements. Impedance–frequency data for various devices can not be explained using the parallel resistance–capacitance (RC) model in the equivalent circuit. However, this was established by incorporating a constant phase element Q (CPE) instead of the capacitance parameter. It should be emphasized that low doping devices in particular are best simulated with two CPE elements, while the data related to other devices are fitted well with a single CPE element. It is also observed from evaluated circuit parameters that the spatial inhomogeneity and disorder are the cause of variability in different samples, which has an excellent correlation with the temperature-dependent current–voltage characteristics. [ABSTRACT FROM AUTHOR]

The valence band electronic structure of GeSe single crystals has been investigated using angle resolved photoemission spectroscopy (ARPES) and x-ray photoelectron spectroscopy. The experimentally observed bands from ARPES, match qualitatively with our LDA-based band structure calculations along the Γ–Z, Γ–Y and Γ–T symmetry directions. The valence band maximum occurs nearly midway along the Γ–Z direction, at a binding energy of −0.5 eV, substantiating the indirect band gap of GeSe. Non-dispersive features associated with surface states and indirect transitions have been observed. The difference in hybridization of Se and Ge 4p orbitals leads to the variation of dispersion along the three symmetry directions. The predominance of the Se 4pz orbitals, evidenced from theoretical calculations, may be the cause for highly dispersive bands along the Γ–T direction. Detailed electronic structure analysis reveals the significance of the cation–anion 4p orbitals hybridization in the valence band dispersion of IV–VI semiconductors. This is the first comprehensive report of the electronic structure of a GeSe single crystal using ARPES in conjugation with theoretical band structure analysis. [ABSTRACT FROM AUTHOR]

Electric field activated charge transport is studied in the metal/polymer/metal device structure of electropolymerized polypyrrole down to 10 K with varying carrier density and disorder. Disorder induced nonlinear behaviour is observed in polypyrrole devices grown at room temperature which is correlated to delocalization of states. The slope parameter of current–voltage characteristics (in log–log scale) increases as the temperature decreases, which indicates the onset of stronger field dependence. The field dependence of mobility becomes dominant as the carrier density decreases. The sharp dip in differential conductance indicates the localization of carriers at low temperatures which reduces the effective number of carriers involved in the transport. [ABSTRACT FROM AUTHOR]

Intense electron beam generation studies were carried out using polymer velvet as a cathode material. The typical electron beam parameters were 250 kV, 15 kA, 100 ns, with a few hundred A cm[?]2 current density. The cathode plasma expansion velocity and the effective initial emission area have been calculated using the perveance data. It was found that the gap closure velocity and the initial emission areas vary randomly on a shot-to-shot basis. In comparison with a graphite cathode, the gap closure velocity of the velvet cathode is less for lower diode gaps, but is much higher for the larger accelerating gaps. One-way analysis of variance was employed to examine the statistical correlation between the diode voltage, current, plasma velocity and the effective emission area for various diode gaps and for two different cathode materials. It was shown that the mean diode voltage, current, plasma velocity and the effective emission area are different for graphite and velvet cathodes whereas the statistical variations of diode voltage and plasma expansion velocities are not cathode material dependent. However, the mean effective emission area is cathode material dependent as are the variances. [ABSTRACT FROM AUTHOR]

Ultrathin layers of polypyrrole (PPy) were electrochemically grown between microelectrodes on a Si/SiO2 substrate. Conducting nanolayers of PPy are directly grown onto ultrathin discontinuous gold (Au) film between the microelectrodes, with thicknesses in the range 10-100 nm. The system therefore forms a novel (PPy/Au) nanocomposite conductor. Atomic force microscopy (AFM) imaging and conductivity measurements indicate that at all thicknesses a relatively uniform film is formed but with significant roughness that reflects the roughness of the metallic island layer. In PPy/Au films with thickness [?]10 nm, the small barriers around the gold islands dominate the conduction, and as the film thickness increases to 100 nm the intrinsic conductivity of highly doped PPy dominates the charge transport. [ABSTRACT FROM AUTHOR]