Methods for Silk Property Analyses across Structural Hierarchies and Scales.

Silk from silkworms and spiders is an exceptionally important natural material, inspiring a range of new products and applications due to its high strength, elasticity, and toughness at low density, as well as its unique conductive and optical properties. Transgenic and recombinant technologies offer great promise for the scaled-up production of new silkworm- and spider-silk-inspired fibres. However, despite considerable effort, producing an artificial silk that recaptures the physico-chemical properties of naturally spun silk has thus far proven elusive. The mechanical, biochemical, and other properties of pre-and post-development fibres accordingly should be determined across scales and structural hierarchies whenever feasible. We have herein reviewed and made recommendations on some of those practices for measuring the bulk fibre properties; skin-core structures; and the primary, secondary, and tertiary structures of silk proteins and the properties of dopes and their proteins. We thereupon examine emerging methodologies and make assessments on how they might be utilized to realize the goal of developing high quality bio-inspired fibres

Regge behaviour of distribution functions and t and x-evolutions of gluon distribution function at low-x

In this paper t and x-evolutions of gluon distribution function from Dokshitzer-Gribov-Lipatov-Altarelli-Parisi(DGLAP) evolution equation in leading order(LO) at low-x, assuming the Regge behaviour of quark and gluon at this limit, are presented. We compare our results of gluon distribution function with MRST 2001, MRST 2004 and GRV '98 parameterizations and show the compatibility of Regge behaviour of quark and gluon distribution functions with perturbative quantum chromodynamics(PQCD) at low-x. We also discuss the limitations of Taylor series expansion method used earlier to solve DGLAP evolution equations, in the Regge behaviour of distribution functions.Comment: 19 pages, 7 figure

Biodegradable Eri silk nanoparticles as a delivery vehicle for bovine lactoferrin against MDA-MB-231 and MCF-7 breast cancer cells

This study used the Eri silk nanoparticles (NPs) for delivering apo-bovine lactoferrin (Apo-bLf) (~2% iron saturated) and Fe-bLf (100% iron saturated) in MDA-MB-231 and MCF-7 breast cancer cell lines. Apo-bLf and Fe-bLf-loaded Eri silk NPs with sizes between 200 and 300 nm (±10 nm) showed a significant internalization within 4 hours in MDA-MB-231 cells when compared to MCF-7 cells. The ex vivo loop assay with chitosan-coated Fe-bLf-loaded silk NPs was able to substantiate its future use in oral administration and showed the maximum absorption within 24 hours by ileum. Both Apo-bLf and Fe-bLf induced increase in expression of low-density lipoprotein receptor-related protein 1 and lactoferrin receptor in epidermal growth factor (EGFR)-positive MDA-MB-231 cells, while transferrin receptor (TfR) and TfR2 in MCF-7 cells facilitated the receptor-mediated endocytosis of NPs. Controlled and sustained release of both bLf from silk NPs was shown to induce more cancer-specific cytotoxicity in MDA-MB-231 and MCF-7 cells compared to normal MCF-10A cells. Due to higher degree of internalization, the extent of cytotoxicity and apoptosis was significantly higher in MDA-MB-231 (EGFR+) cells when compared to MCF-7 (EGFR-) cells. The expression of a prominent anticancer target, survivin, was found to be downregulated at both gene and protein levels. Taken together, all the observations suggest the potential use of Eri silk NPs as a delivery vehicle for an anti-cancer milk protein, and indicate bLf for the treatment of breast cancer

Impact of tranexamic acid on coagulation parameters in patients undergoing total knee replacement surgeries under tourniquet: an observational study

Background: A growing body of evidence has shown Tranexamic Acid (TXA) is effective in decreasing perioperative blood loss and transfusion requirements in both primary and revision joint arthroplasty. TXA is a synthetic drug which limits blood loss through inhibition of fibrinolysis and clot degradation. It helps reduce requirement of colloids and crystalloids and hence provides better haemodynamic stability. The aim of this study was to detect the effect of tranexamic acid on coagulation parameters and effect on bleeding in knee replacement surgeries performed under tourniquet.Methods: Patients undergone surgeries of Total Knee Replacement (TKR) performed under tourniquet were included in the study. A single dosage of 20 mg/kg per body weight of tranexamic acid was administered after application of a tourniquet. Three times blood sample was collected, and coagulation parameters were recorded and compared. The first sample was collected at the time of TXA injection and application of a tourniquet, second after 4 hours and third after 24 hours post TXA injection. Coagulation parameters noted were analyzed using Statistical analysis by SPSS software. All parameters were compared in relation to baseline i.e. at the time of TXA injection.Results: On comparison of demographic profile, morbidity, sofa score and hemodynamic parameters there was the insignificant difference (P > 0.05). Repeated measures of ANOVA at 95% Confidential Interval P value was 0.000 which is less than the significant level that is 0.05 so that value of Platelet Function (PF), Activated Coagulation Time (ACT) and Clot Rate (CR) at 0 hrs, 04 hrs and 24 hrs was statistically significant. Correlation between blood loss and difference of the value of ACT at 0 hrs and 04 hrs is a small negative correlation but statistically nonsignificant (P value is 0.359).Conclusions: After TXA administration there is a change in coagulation parameters like an Activated Coagulation Time (ACT), Platelet Function (PF), and Clot Rate (CR) measured at three intervals, hence it can be a guide to detect early derangement in the coagulation profile in a patient undergoing knee replace surgery. TXA correlation between blood loss with changes in parameters of coagulation i.e. ACT, PF and CR were noted but not significant

Lowering solar mixing angle in inverted hierarchy without charged lepton corrections

In the present work, the inverted hierarchical neutrino mass model which is characterised by opposite CP parity in the first two mass eigenvalues $(m_1,-m_2,m_3)$, is studied in order to lower the predicted value of solar mixing angle $\tan^2\theta_{12}$, from the tri-bimaximal mixing (TBM), without sacrificing the conditions of maximal atmospheric mixing angle and zero reactor angle. The present attempt is different from the earlier approach where the correction from the charged lepton mass matrix is included in the leptonic mixing matrix to lower the prediction on solar mixing angle. The lowering of the solar mixing angle without charged lepton correction, can be obtained through the variation of the input value of a flavour twister term present in the texture of neutrino mass matrix having a 2-3 symmetry. The present analysis agrees with the latest experimental bounds on neutrino mass parameters and also represents an important result on the survival of the inverted hierarchical neutrino mass models having opposite CP parity in the first two eigenvalues.Comment: 10 pages, two figures. Accepted for publication in Journal of Physics G:Nuclear and Particle Physic

Deviation from tri-bimaximal mixings in two types of inverted hierarchical neutrino mass models

An attempt is made to explore the possibility for deviations of solar mixing angle ($\theta_{12}$) from tri-bimaximal mixings, without sacrificing the predictions of maximal atmospheric mixing angle ($\theta_{23}=\pi/4$) and zero reactor angle ($\theta_{13}=0$). We find that the above conjecture can be automatically realised in the inverted hierarchical neutrino mass model having 2-3 symmetry, in the basis where charged lepton mass matrix is diagonal. For the observed ranges of $\bigtriangleup m^2_{21}$ and \bigtriangleup m^2_{23], we calculate the predictions on $\tan^2\theta_{12}=0.5, 0.45, 0.35$ for different input values of the parameters in the neutrino mass matrix. We also observe a possible crossing over from one type of inverted hierarchical model having same CP parity (Type-IHA) to other type having opposite CP parity (Type-IHB). Such neutrino mass matrices can be obtained from the canonical seesaw formula using diagonal form of Dirac neutrino mass matrix and non-diagonal texture of right-handed Majorana mass matrix, and may have important implications in model building using discrete as well as non-abelian symmetry groups.Comment: 13 pages, 7 figure

Regge behaviour of distribution functions and evolution of gluon distribution function in Next-to-Leading order at low-x

Evolution of gluon distribution function from Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equation in next-to-leading order (NLO) at low-x is presented assuming the Regge behaviour of quarks and gluons at this limit. We compare our results of gluon distribution function with MRST2004, GRV98LO and GRV98NLO parameterizations and show the compatibility of Regge behaviour of quark and gluon distribution functions with perturbative quantum chromodynamics (PQCD) at low-x.Comment: 12 pages, 4 figure

Pathology of co-contamination of mycotoxins in poultry farms of Aizawl district of Mizoram

The study was conducted to investigate the naturally occurring pathology of co-contamination of mycotoxins in poultry farms in Aizawl, Mizoram. During the investigation, different chicken farms (n=73) were surveyed for occurrence of disease and mortality. The feed samples collected from affected farms were tested for the presence of aflatoxin, ochratoxin and zearalenone by ELISA kits. The dead birds were subjected to necropsy. Visceral organs from the dead birds were processed for histopathological studies. Fourteen feed samples, out of 49 tested (28.5%) were found affected by co-contamination with aflatoxin, ochratoxin and zearalenone. In this study, the mean level of aflatoxin, ochratoxin and zearalenone was 13.49693 ppb, 4.296286 ppb and 81.74543 ppb, respectively. Clinical signs were ruffled feathers, depression, dullness, huddling, poor growth, anorexia. Necropsy revealed pathological lesions in visceral and lymphoid organs. Histopathological findings were inflammations, degenerative, and necrotic lesions in liver and kidneys. A perusal of available literature did not reveal any study on the presence of co-contamination of Mycotoxicosis in poultry and poultry feed in Aizawl

Obesity-induced insulin resistance in human skeletal muscle is characterised by defective activation of p42/p44 MAP kinase

Insulin resistance (IR), an impaired cellular, tissue and whole body response to insulin, is a major pathophysiological defect of type 2 diabetes mellitus. Although IR is closely associated with obesity, the identity of the molecular defect(s) underlying obesity-induced IR in skeletal muscle remains controversial; reduced post-receptor signalling of the insulin receptor substrate 1 (IRS1) adaptor protein and downstream effectors such as protein kinase B (PKB) have previously been implicated. We examined expression and/or activation of a number of components of the insulin-signalling cascade in skeletal muscle of 22 healthy young men (with body mass index (BMI) range, 20–37 kg/m2). Whole body insulin sensitivity (M value) and body composition was determined by the hyperinsulinaemic (40 mU. min−1.m−2.), euglycaemic clamp and by dual energy X-ray absorptiometry (DEXA) respectively. Skeletal muscle (vastus lateralis) biopsies were taken before and after one hour of hyperinsulinaemia and the muscle insulin signalling proteins examined by western blot and immunoprecipitation assay. There was a strong inverse relationship between M-value and BMI. The most striking abnormality was significantly reduced insulin-induced activation of p42/44 MAP kinase, measured by specific assay, in the volunteers with poor insulin sensitivity. However, there was no relationship between individuals' BMI or M-value and protein expression/phosphorylation of IRS1, PKB, or p42/44 MAP kinase protein, under basal or hyperinsulinaemic conditions. In the few individuals with poor insulin sensitivity but preserved p42/44 MAP kinase activation, other signalling defects were evident. These findings implicate defective p42/44 MAP kinase signalling as a potential contributor to obesity-related IR in a non-diabetic population, although clearly multiple signalling defects underlie obesity associated IR