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In the present day knowledge, there is an massive requisite of developing appropriate data communication interfaces for real time embedded systems. Field Programmable Gate Array (FPGA) gives various means, which can be programmed for constructing an effective embedded unit. The FPGA configuration is generally specified using a hardware description language (HDL). VHDL (VHSIC hardware description language) is a hardware description language used in electronic design automation to explain digital and mixed-signal structures such as field programmable gate arrays (FPGA) and integrated circuits. This work proposes a technique to design and implement a 32 bit ALU which is a digital circuit that performs arithmetic and logical operations on Xilinx ISE using VHDL.

In the present study, we have designed a laser-induced fluorescence (LIF) based instrumentation and developed a sensitive methodology for the effective separation, visualization, identification and analysis of proteins on a single platform. In this method, intrinsic fluorescence spectra of proteins were detected after separation on 1 or 2 dimensional Sodium Dodecyl Sulfate-Tris(2-carboxyethyl)phosphine (SDS-TCEP) polyacrylamide gel electrophoresis (PAGE) and the data were analyzed. The MATLAB assisted software was designed for the development of PAGE fingerprint for the visualization of protein after 1- and 2-dimensional protein separation. These provided objective parameters of intrinsic fluorescence intensity, emission peak, molecular weight and isoelectric point using a single platform. Further, the current architecture could differentiate the overlapping proteins in the PAGE gels which otherwise were not identifiable by conventional staining, imaging and tagging methods. Categorization of the proteins based on the presence or absence of tyrosine or tryptophan residues and assigning the corresponding emission peaks (309-356 nm) with pseudo colors allowed the detection of proportion of proteins within the given spectrum. The present methodology doesn't use stains or tags, hence amenable to couple with mass spectroscopic measurements. This technique may have relevance in the field of proteomics that is used for innumerable applications.

Polymers with a cyclic topology exhibit a range of unique and potentially useful physical properties, including reduced rates of degradation and increased rates of diffusion in bulk relative to linear analogs. However, the synthesis of high purity cyclic polymers and verification of their structural purity remain challenging. The copper-catalyzed azide–alkyne “click” cyclization route toward cyclic polymers has been widely used, due to its synthetic ease and its compatibility with diverse polymer backbones. Yet unoptimized click cyclization conditions have been observed to generate oligomeric byproducts. In order to optimize these cyclization conditions, and to better understand the structure of the higher molecular weight oligomers, these impurities have been isolated and characterized. Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI–ToF) MS is a particularly valuable characterization tool and was used to determine that the high molecular weight impurities are predominantly cyclic oligomers. It should also be noted that the rapid analysis and small analyte requirements of this MS technique make it particularly attractive as a general tool for elucidating polymer architecture.

In spite of many efforts for early detection of breast cancer, there is still lack of technology for immediate implementation. In the present study, the potential photoacoustic spectroscopy was evaluated in discriminating breast cancer from normal, involving blood serum samples seeking early detection. Three photoacoustic spectra in time domain were recorded from each of 20 normal and 20 malignant samples at 281nm pulsed laser excitations and a total of 120 spectra were generated. The time domain spectra were then Fast Fourier Transformed into frequency domain and 116.5625 - 206.875 kHz region was selected for further analysis using a combinational approach of wavelet, PCA and logistic regression. Initially, wavelet analysis was performed on the FFT data and seven features (mean, median, area under the curve, variance, standard deviation, skewness and kurtosis) from each were extracted. PCA was then performed on the feature matrix (7x120) for discriminating malignant samples from the normal by plotting a decision boundary using logistic regression analysis. The unsupervised mode of classification used in the present study yielded specificity and sensitivity values of 100% in each respectively with a ROC - AUC value of 1. The results obtained have clearly demonstrated the capability of photoacoustic spectroscopy in discriminating cancer from the normal, suggesting its possible clinical implications.

The method is used to register the laryngeal behavior indirectly by measuring change in the electrical impedance across the throat during speak or voice. In this Electroglottography (EGG) signal acquisition, the electrodes are made of steel. They have the form of rectangles covering an area of 10.75 cm2. It is designed as a ring electrode encircling each of the two other electrodes. The electrodes are mounted on a flexible band whose length is adjusted to hold the electrodes in a steady position and to still allow the subject to comfortably speak and breathe naturally. The electrodes are mounted on a small holder which is pressed against the throat by hand. A signal generator supplies an AC sinusoidal current usually ranging from 2 MHz. The RF carrier signal is amplitude modulated by the modulating speech/ voice signal and the demodulated signal is extracted. The variations in the signal correspond to the vocal fold abduction/laryngeal movement. For normal and pathology conditions, the results are recorded. These values form a feature vector, which reveals information regarding pathology. Principal Component Analysis technique (PCA) is used for classification, giving successful results for the specific data set considered.

In this study, we present the evaluation of two new ternary ligand (99m)Tc complexes [(99m)Tc(HYNIC tetramer)(tricine)(L)] [L=isonicotinic acid (ISONIC) and 2,5-pyridinedicarboxylic acid (PDA)] as potential radiotracers for tumor imaging. Athymic nude mice bearing MDA-MB-435 human breast cancer xenografts were used to evaluate their biodistribution and metabolic properties. Solution stability data showed that [(99m)Tc(HYNIC tetramer)(tricine)(L)] (L=ISONIC and PDA) had significant decomposition (14% and 35%, respectively) at 6 h in the absence of excess ISONIC or PDA coligand. Biodistribution data clearly showed that [(99m)Tc(HYNIC tetramer)(tricine)(PDA)] had a much lower uptake in most organs of interest than [(99m)Tc(HYNIC tetramer)(tricine)(ISONIC)] during the 2-h study period. Results from metabolism studies revealed that approximately 50% of [(99m)Tc(HYNIC tetramer)(tricine)(ISONIC)] remained intact in fecal samples at 120 min postinjection, whereas only 10% of [(99m)Tc(HYNIC tetramer)(tricine)(PDA)] remained intact in fecal samples. The extent of metabolism correlated well with radiotracer solution stability. The results from this and our previous studies clearly demonstrated that coligands [trisodium triphenylphosphine-3,3',3''-trisulfonate (TPPTS), ISONIC and PDA] have a significant impact on the tumor uptake, excretion kinetics and metabolism of the (99m)Tc-labeled cyclic RGDfK tetramer. Among the three radiotracers evaluated in this tumor-bearing animal model, [(99m)Tc(HYNIC tetramer)(tricine)(TPPTS)] remained the best with respect to blood clearance, tumor uptake and target/background ratios.

This report presents synthesis and evaluation of the 64Cu-labeled triphenylphosphonium (TPP) cations as new radiotracers for imaging tumors by positron emission tomography. Biodistribution properties of 64Cu-L1, 64Cu-L2, 64Cu-L3, and 99mTc-Sestamibi were evaluated in athymic nude mice bearing U87MG human glioma xenografts. The most striking difference is that 64Cu-L1, 64Cu-L2, and 64Cu-L3 have much lower heart uptake (0.6% ID/g) than 99mTc-Sestamibi ( approximately 18% ID/g) at30 min p.i. Their tumor/heart ratios increase steadily from approximately 1 at 5 min p.i. to approximately 5 at 120 min p.i. The tumor/heart ratio of 64Cu-L3 is approximately 40 times better than that of 99mTc-Sestamibi at 120 min postinjection. Results from in vitro assays show that 64Cu-L1 is able to localize in tumor mitochondria. The tumor is clearly visualized in the tumor-bearing mice administered with 64Cu-L1 as 30 min postinjection. The 64Cu-labeled TPP/TPA cations are very selective radiotracers that are able to provide the information of mitochondrial bioenergetic function in tumors by monitoring mitochondrial potential in a noninvasive fashion.

Integrin alphavbeta3 plays a critical role in tumor angiogenesis and metastasis. Radiolabeled RGD peptides that are integrin alphavbeta3-specific are very useful for noninvasive imaging of integrin expression in rapidly growing and metastatic tumors. In this study, we determined the binding affinity of E{E[c(RGDfK)]2}2 (tetramer) and its 6-hydrazinonicotinamide conjugate (HYNIC-tetramer) against the binding of 125I-echistatin to the integrin alphavbeta3-positive MDA-MB-435 breast cancer cells. The athymic nude mice bearing MDA-MB-435 xenografts were used to evaluate the potential of ternary ligand complex [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] (TPPTS = trisodium triphenylphosphine-3,3',3' '-trisulfonate) as a new radiotracer for imaging breast cancer integrin alphavbeta3 expression by single photon emission computed tomography (SPECT). It was found that the binding affinity of tetramer (IC50 = 51 +/- 11 nM) was slightly higher than that of its dimeric analogue (IC50 = 78 +/- 27 nM) and is comparable to that of the HYNIC-tetramer conjugate (IC50 = 55 +/- 11 nM) within the experimental error. Biodistribution data showed that [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] had a rapid blood clearance (4.61 +/- 0.81 %ID/g at 5 min postinjection (p.i.) and 0.56 +/- 0.12 %ID/g at 120 min p.i.) and was excreted mainly via the renal route. [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] had high tumor uptake with a long tumor retention (5.60 +/- 0.87 %ID/g and 7.30 +/- 1.32 %ID/g at 5 and 120 min p.i., respectively). The integrin alphavbeta3-specificity was demonstrated by co-injection of excess E[c(RGDfK)]2, which resulted in a significant reduction in tumor uptake of the radiotracer. The metabolic stability of [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] was determined by analyzing urine and feces samples from the tumor-bearing mice at 120 min p.i. In the urine, about 20% of [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] remained intact while only approximately 15% metabolized species was detected in feces. SPECT images displayed significant radiotracer localization in tumor with good contrast as early as 1 h p.i. The high tumor uptake and fast renal excretion make [99mTc(HYNIC-tetramer)(tricine)(TPPTS)] a promising radiotracer for noninvasive imaging of the integrin alphavbeta3-positive tumors by SPECT.

The current study reports the photoacoustic spectroscopy-based assessment of breast tumor progression in a nude mice xenograft model. The tumor was induced through subcutaneous injection of MCF-7 cells in female nude mice and was monitored for 20 days until the tumor volume reached 1000 mm3. The tumor tissues were extracted at three different time points (days 10, 15, and 20) after tumor inoculation and subjected to photoacoustic spectral recordings in time domain ex vivo at 281 nm pulsed laser excitations. The spectra were converted into the frequency domain using the fast Fourier transformed tools of MATLAB® algorithms and further utilized to extract seven statistical features (mean, median, area under the curve, variance and standard deviation, skewness and kurtosis) from each time point sample to assess the tumor growth with wavelet principal component analysis based logistic regression analysis performed on the data. The prediction accuracies of the analysis for day 10 versus day 15, day 15 versus day 20, and day 10 versus day 20 were found to be 92.31, 87.5, and 95.2%, respectively. Also, receiver operator characteristics area under the curve analysis for day 10 versus day 15, day 15 versus day 20, and day 10 versus day 20 were found to be 0.95, 0.85, and 0.93, respectively. The ability of photoacoustic measurements in the objective assessment of tumor progression has been clearly demonstrated, indicating its clinical potential.

We describe a rare case of type B thoracic aortic dissection resulting from a forceful sneeze in a 57-year-old man. The presenting clinical features were not typical and consisted of pleuritic chest pain and breathlessness following a forceful sneeze. There was no haemodynamic compromise. The diagnosis was made incidentally when he underwent a CT pulmonary angiography as part of pulmonary embolism work-up.

The authors describe a case of platypnoea orthodeoxia syndrome in an 83-year-old man with a fenestrated atrial septal defect and severe coronary artery disease. The patient had been admitted to hospital six times in the previous year with acute breathlessness, attributed to paroxysmal atrial fibrillation. The patient’s symptoms resolved completely following surgical repair of the defect and coronary artery bypass grafting.

The surface modification of deep-cavity cavitands has been demonstrated by using the azide-alkyne “click” coupling to attach dendritic macromolecules or linear polymers onto their periphery. The resulting set of macromolecular cavitands exhibited tuneable solubility yet retained the ability to encapsulate guest molecules.

Recent advances in the resolving power of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) enable the detailed characterization of linear homopolymers, and in particular provide invaluable data for the determination of their end-group functionalities. With the growing importance of macromolecular coupling reactions in building complex polymer architectures, the ability to accurately monitor end-group transformations is becoming increasingly important for synthetic polymer chemists. This tutorial demonstrates the application of MALDI-TOF MS in determining both end-group functionalities and their transformations for linear homopolymers. Examples of both polycaprolactone and polystyrene are examined, and the strengths and weaknesses of various approaches to data analysis are given.

A new macrocyclic chelator, 6,6',6''-(1,4,7-triazonane-1,4,7-triyl)tris(methylene)tris(5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one) (H3NOKA), was synthesized from the reaction of 1 equiv of 1,4,7-triazacyclononane (TACN) and 3 equiv of kojic acid (KA) in the presence of excess formaldehyde. The reaction of H 3NOKA with metal salt forms complexes M(NOKA) (M = Ga, In, and Fe) and Cu(HNOKA). H 3NOKA and its complexes, M(NOKA) (M = Ga, In, and Fe) and Cu(HNOKA), have been characterized by IR, UV/vis, ESI-MS, and elemental analysis. Structures of Ga(NOKA), Fe(NOKA), and Cu(HNOKA) were determined by X-ray crystallography. In the solid state, Ga(NOKA) and Fe(NOKA) are isostructural with the distorted octahedral geometry. In contrast, Cu(HNOKA) has the distorted square-pyramidal coordination geometry in which NOKA is pentadentate with three amine-N and two enolate-O atoms bonding to Cu(II) and one of three 3-hydroxy-4-pyrone chelating arms remaining free and protonated. The cyclic voltammogram of Fe(NOKA) exhibits a quasi-reversible redox wave at E(1/2) = -0.53 mV from the Fe(III)(NOKA)/Fe(II)(NOKA)(-) couple, whereas Cu(HNOKA) shows an irreversible one-electron reduction of Cu(II)(HNOKA)/Cu(I)(HNOKA)(-) at E(pc) = -0.87 V. These low redox potentials indicate that Fe(III) in Fe(NOKA) and Cu(II) in Cu(HNOKA) are preferentially stabilized by NOKA. The variable-temperature (1)H NMR spectral data show that Ga(NOKA) is more rigid than that of In(NOKA) in the solution. The results from this study suggest that the C-substituted NOKA derivatives might be useful as bifunctional chelators for (68)Ga-labeling of small biomolecules, while the corresponding N-substituted analogues are probably more suitable for preparation of the (64)Cu-based target-specific radiotracers.

The method is used to register the laryngeal behavior indirectly by measuring change in the electrical impedance across the throat during speak or voice. The RF carrier signal is amplitude modulated by the modulating speech/ voice signal and the dc component from the demodulated signal is extracted. The variations in the dc component corresponds to the vocal fold abduction/laryngeal movement. For normal and pathology conditions the results are recorded. These values form a feature vector which reveal information regarding pathology. Then a classical multilayer feed forward neural network with back propagation algorithm is employed to serve as a classifier of the feature vector, giving 100% successful results for the specific data set considered.