78 research outputs found
Magnetic Studies on Spinel Ferrite Nanoparticles and Bulk Samples Synthesized by Citrate Combustion Route
We report structural, microstructural and magnetic studies of ZnFe2O4, MnFe2O4 and mixed Mn-Ni-Zn ferrites in nanoparticles and bulk forms. Polycrystalline samples were prepared by citrate combustion synthesis, which resulted in homogeneous and nanograin powders. Particle sizes estimated from the XRD and SEM were found to be below 100 nm for the calcined powders (600 degrees C) and above 300 nm range for the sintered (1200 degrees C) samples. Substitution of Ni and Zn for Mn enhanced the saturation magnetization and coercivity, because of the redistribution between octahedral and tetrahedral iron sites. Curie temperature were found to be higher for the calcined powders as compared to corresponding sintered samples due to particle size effects
Microwave spin resonance investigation on the effect of the post-processing annealing of CoFe2O4 nanoparticles
A novel investigation on the finite-size effects on the spin resonance properties of cobalt ferrite (CoFe2O4) nanoparticles has been performed using a room temperature ferromagnetic resonance (FMR) technique. A single broad spectrum was obtained for the CoFe2O4 nanoparticle samples, which indicated that all the samples were showing ferromagnetic characteristics. An asymmetric FMR line shape with a hefty trailing section was obtained due to the high magneto-crystalline anisotropy in CoFe2O4 nanoparticles, which changed with the size distribution. The resonance field for the samples shifted to a higher value due to the increase in the magneto-crystalline anisotropy in the CoFe2O4 nanoparticles with an increase in size. A systematic change in the resonance field and line width was observed with the change in the size distribution of the particles. Initially, it decreased with an increase in the size of the particles and increased after the critical size range. The critical size range is the imprint of the shift of the magnetic domain from a single domain to multi domain. The line width increased at higher annealing temperatures due to the enhancement in the dipole-dipole interaction, which led to a higher spin concentration as well as magneto-crystalline anisotropy. Furthermore, the saturation magnetization (M-s) as well as 'M-r/M-s' increased from 37.7 to 71.4 emu g(-1) and 0.06 to 0.31, respectively. The highest coercivity (750.9 Oe) and anisotropy constant (4.62 x 10(4) erg cm(-3)) were found for the sample annealed at 700 degrees C, which can be corroborated by the literature as the critical annealing temperature at which CoFe2O4 nanoparticles shift from single domain nanoparticles to multi-domain nanoparticles. Post-processing annealing is critical in advanced processing techniques and spin dynamics plays a vital role in various interdisciplinary areas of applications
Exploratory study of macrophage polarization and spatial distribution in colorectal cancer liver metastasis: a pilot study
BackgroundThe liver is the most typical site of metastatic disease for patients with colorectal cancer (CRC), and up to half the patients with CRC will develop colorectal liver metastasis (CLM). Studying the tumor microenvironment, particularly macrophages and their spatial distribution, can give us critical insight into treatment.MethodsTen CLMs (five treatment-naĂŻve and five postâneoadjuvant chemotherapy) were stained with multiplex immunofluorescence panels against cytokeratins, CD68, Arg1, CD206, CD86, CD163, PD-L1, and MRP8-14. Densities of cell phenotypes and their spatial distribution in the tumor center and the normal liverâtumor interface were correlated with clinicopathological variables.ResultsM2 macrophages were the predominant subtype in both the tumor center and the periphery, with a relatively higher density at the periphery. The larger tumors, more than 3.9Â cm, were associated with higher densities of total CD68+ macrophages and CD68+CD163+ CD206neg and CD68+CD206+ CD163neg M2 macrophage subtypes. Total macrophages in the tumor periphery demonstrated significantly greater proximity to malignant cells than did those in the tumor center (p=0.0371). The presence of higher than median CD68+MRP8-14+CD86neg M1 macrophages in the tumor center was associated with poor overall survival (median 2.34 years) compared to cases with lower than median M1 macrophages at the tumor center (median 6.41 years) in univariate analysis.ConclusionThe dominant polarization of the M2 macrophage subtype could drive new therapeutic approaches in CLM patients
Allelopathic effect of Celtis australis on germination and growth parameters of some important food crops of the Garhwal Himalayas
Present study was conducted to assess the allelopathic effect of leaf and bark aqueous extracts of Celtis australis on Triticum aestivum, Hordeum vulgare, Brassica rapa, Lens culinaris and Vigna umbellate under In-vitro condition. Different leaf and bark aqueous extracts 5%, 10%, and 15% were used to irrigate the seeds of test crops. The results revealed that the concentration dependent significant (p=0.05) inhibitory effect of aqueous leaf and bark extracts on germination, root and shoot length of all the test crops. Among all the test crops Triticum aestivum was found most sensitive where the germination percentage was reduced down to 46.0% by the leaf extract (15%) as compared to control (82.3%), while the maximum inhibition in the root length of Lens culinaris (0.5 cm) by 10% leaf extract was observed as compare to control (8.2 cm). In shoot length maximum inhibitory effect was observed in Hordeum vulgare (3.5 cm) as compared to control (13.3 cm). Similarly, the bark extract showed the maximum inhibition in germination percentage of Lens culinaris (41.6%) at 15% concentration as compare to control (70.0%) while the maximum inhibition for the root length was recorded in Triticum aestivum (1.9 cm) at 15% concentration as compare to control (17.3 cm). In shoot length maximum inhibition was observed for Triticum aestivum (1.3 cm) at 10% extract level as compare to control (13.4 cm), while Vigna umbellate (5.5 cm) at 15% concentration showed stimulatory effect as compare to control (3.4 cm) exceptionally. Finally, it is concluded that Vigna umbellate exhibited the maximum tolerance against leaf and bark aqueous and might be a better option for intercropping with C. australis. However, the allelopathic effect on the other test crops can be minimized by removing the fallen leaves from the agricultural fields
Bleeding disorders in the tribe: result of consanguineous in breeding
<p>Abstract</p> <p>Objective</p> <p>To determine the frequency and clinical features of bleeding disorders in the tribe as a result of consanguineous marriages.</p> <p>Design</p> <p>Cross Sectional Study</p> <p>Introduction</p> <p>Countries in which consanguinity is a normal practice, these rare autosomal recessive disorders run in close families and tribes. Here we describe a family, living in village Ali Murad Chandio, District Badin, labeled as haemophilia.</p> <p>Patients & Methods</p> <p>Our team visited the village & developed the pedigree of the whole extended family, up to seven generations. Performa was filled by incorporating patients, family history of bleeding, signs & symptoms, and bleeding from any site. From them 144 individuals were screened with CBC, bleeding time, platelet aggregation studies & RiCoF. While for PT, APTT, VWF assay and Factor VIII assay, samples were kept frozen at -70 degrees C until tested.</p> <p>Results</p> <p>The family tree of the seven generations comprises of 533 individuals, 63 subjects died over a period of 20 years and 470 were alive. Out of all those 144 subjects were selected on the basis of the bleeding history. Among them 98(68.1%) were diagnosed to have a bleeding disorder; 44.9% patients were male and 55.1% patients were female. Median age of all the patients was 20.81, range (4 months- 80 yrs). The results of bleeding have shown that majority had gum bleeding, epistaxis and menorrhagia. Most common bleeding disorder was Von Willebrand disease and Platelet functional disorders.</p> <p>Conclusion</p> <p>Consanguineous marriages keep all the beneficial and adversely affecting recessive genes within the family; in homozygous states. These genes express themselves and result in life threatening diseases. Awareness, education & genetic counseling will be needed to prevent the spread of such common occurrence of these bleeding disorders in the community.</p
Modulation of Host miRNAs Transcriptome in Lung and Spleen of Peste des Petits Ruminants Virus Infected Sheep and Goats
Peste des petits ruminants (PPR) is one of the highly contagious viral disease, characterized by fever, sore mouth, conjunctivitis, gastroenteritis, and pneumonia, primarily affecting sheep and goats. Reports suggested variable host response in goats and sheep and this host response vis-a-vis the expression of microRNAs (miRNAs) has not been investigated. Here, miRNAs were sequenced and proteomics data were generated to identify the role of differentially expressed miRNA (DEmiRNA) in PPR virus (PPRV) infected lung and spleen tissues of sheep and goats. In lungs, 67 and 37 DEmiRNAs have been identified in goats and sheep, respectively. Similarly, in spleen, 50 and 56 DEmiRNAs were identified in goats and sheep, respectively. A total of 20 and 11 miRNAs were found to be common differentially expressed in both the species in PPRV infected spleen and lung, respectively. Six DEmiRNAsâmiR-21-3p, miR-1246, miR-27a-5p, miR-760-3p, miR-320a, and miR-363 were selected based on their role in viral infections, apoptosis, and fold change. The target prediction analysis of these six selected DEmiRNAs from the proteome data generated, revealed involvement of more number of genes in lung and spleen of goats than in sheep. On gene ontology analysis of host target genes these DEmiRNAs were found to regulate several immune response signaling pathways. It was observed that the pathways viz. T cell receptor signaling, Rap1 signaling, Toll-like receptor signaling, and B cell receptor signaling governed by DEmiRNAs were more perturbed in goats than in sheep. The data suggests that PPRV-induced miR-21-3p, miR-320a, and miR-363 might act cooperatively to enhance viral pathogenesis in the lung and spleen of sheep by downregulating several immune response genes. The study gives an important insight into the molecular pathogenesis of PPR by identifying that the PPRVâIzatnagar/94 isolate elicits a strong host response in goats than in sheep
Tspan8 is expressed in breast cancer and regulates E-cadherin/catenin signalling and metastasis accompanied by increased circulating extracellular vesicles
Tspan8 exhibits a functional role in many cancer types including pancreatic, colorectal, oesophagus carcinoma, and melanoma. We present a first study on the expression and function of Tspan8 in breast cancer. Tspan8 protein was present in the majority of human primary breast cancer lesions and metastases in the brain, bone, lung, and liver. In a syngeneic rat breast cancer model, Tspan8 tumours formed multiple liver and spleen metastases, while Tspan8 tumours exhibited a significantly diminished ability to metastasise, indicating a role of Tspan8 in metastases. Addressing the underlying molecular mechanisms, we discovered that Tspan8 can mediate upâregulation of Eâcadherin and downâregulation of Twist, p120âcatenin, and βâcatenin target genes accompanied by the change of cell phenotype, resembling the mesenchymalâepithelial transition. Furthermore, Tspan8 cells exhibited enhanced cellâcell adhesion, diminished motility, and decreased sensitivity to irradiation. As a regulator of the content and function of extracellular vesicles (EVs), Tspan8 mediated a severalâfold increase in EV number in cell culture and the circulation of tumourâbearing animals. We observed increased protein levels of Eâcadherin and p120âcatenin in these EVs; furthermore, Tspan8 and p120âcatenin were coâimmunoprecipitated, indicating that they may interact with each other. Altogether, our findings show the presence of Tspan8 in breast cancer primary lesion and metastases and indicate its role as a regulator of cell behaviour and EV release in breast cancer
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Stochastic flowering phenology in Dactylis Glomerata populations described by Markov chain modelling
Understanding the relationship between flowering patterns and pollen dispersal is important in climate change modelling, pollen forecasting, forestry and agriculture. Enhanced understanding of this connection can be gained through detailed spatial and temporal flowering observations on a population level, combined with modelling simulating the dynamics. Species with large distribution ranges, long flowering seasons, high pollen production and naturally large populations can be used to illustrate these dynamics. Revealing and simulating species-specific demographic and stochastic elements in the flowering process will likely be important in determining when pollen release is likely to happen in flowering plants. Spatial and temporal dynamics of eight populations of Dactylis glomerata were collected over the course of two years to determine high-resolution demographic elements. Stochastic elements were accounted for using Markov Chain approaches in order to evaluate tiller-specific contribution to overall population dynamics. Tiller-specific developmental dynamics were evaluated using three different RV matrix correlation coefficients. We found that the demographic patterns in population development were the same for all populations with key phenological events differing only by a few days over the course of the seasons. Many tillers transitioned very quickly from non-flowering to full flowering, a process that can be replicated with Markov Chain modelling. Our novel approach demonstrates the identification and quantification of stochastic elements in the flowering process of D. glomerata, an element likely to be found in many flowering plants. The stochastic modelling approach can be used to develop detailed pollen release models for Dactylis, other grass species and probably other flowering plants
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