Giant Ossifying Lipoma of the Hand: A Case Report and Review of Literature.

Lipomas are one of the most common benign tumors of the body, characterized by a slow-growing, painless mass that rarely causes symptoms. Bone metaplasia among the mature adipose cells, however, is a rare condition called osteolipoma. In this article, we present a case report of a 61-year-old lady with a giant osteolipoma of the hand. After a surgical extirpation, she showed a fast recovery, and no recurrence during the two-year follow-up period was observed. We aimed to make a literature review of this pathology, discussing the symptoms, diagnosis, and management of this rare condition.

The Effect of Post Deposition Treatment on Properties of ALD Al-Doped ZnO Films.

In this paper, aluminum-doped zinc oxide (ZnO:Al or AZO) thin films are grown using atomic layer deposition (ALD) and the influence of postdeposition UV-ozone and thermal annealing treatments on the films' properties are investigated. X-ray diffraction (XRD) revealed a polycrystalline wurtzite structure with a preferable (100) orientation. The crystal size increase after the thermal annealing is observed while UV-ozone exposure led to no significant change in crystallinity. The results of the X-ray photoelectron spectroscopy (XPS) analyses show that a higher amount of oxygen vacancies exists in the ZnO:Al after UV-ozone treatment, and that the ZnO:Al, after annealing, has a lower amount of oxygen vacancies. Important and practical applications of ZnO:Al (such as transparent conductive oxide layer) were found, and its electrical and optical properties demonstrate high tunability after postdeposition treatment, particularly after UV-Ozone exposure, offers a noninvasive and easy way to lower the sheet resistance values. At the same time, UV-Ozone treatment did not cause any significant changes to the polycrystalline structure, surface morphology, or optical properties of the AZO films.

Fabrication and spectroscopic characterization of graphene transparent electrodes on flexible cyclo-olefin substrates for terahertz electro-optic applications.

We demonstrate graphene on flexible, low-loss, cyclo-olefin polymer films as transparent electrodes for terahertz electro-optic devices and applications. Graphene was grown by chemical vapor deposition and transferred to cyclo-olefin polymer substrates by the thermal release tape method as layers on an approximate area of 4 cm2. The structural and electromagnetic properties of the graphene samples as well as their spatial variation were systematically mapped by means of µRaman, terahertz time-domain and mid-infrared spectroscopy. Thanks to the small thickness and very low intrinsic absorption of the employed substrates, both high transmittance and conductivity were recorded, demonstrating the suitability of the technique for the fabrication of a new class of transparent and flexible electrodes working in the terahertz spectrum.

Flexible light valves using polymer-dispersed liquid crystals and TiO2/Ag/TiO2 multilayers.

The era of flexible optoelectronics demands development of wearable and bendable structures, foldable touch screens, paper-like displays, and curved and flexible solid-state lighting devices. Here, we demonstrate the fabrication of highly flexible light valves using polymer-dispersed liquid crystal (PDLC) and TiO2/Ag/TiO2 transparent conductive films. TiO2/Ag/TiO2 multilayers were prepared by magnetron sputtering technique on polyethylene terephthalate (PET) substrates at room temperature. By keeping the equivalent TiO2 layers and varying the deposition time of the Ag layer, proper metal nanograins on TiO2 planar plane were formed, providing the best tradeoff between the transmittance, sheet resistance and bending ability. The results are validated by numerical simulations that suggest the best match between the deposition time and individual layer thickness. Based on the performed characteristics of TiO2/Ag/TiO2/PET structures, several flexible light valves are fabricated and characterized. The sheet resistance values of TiO2/Ag/TiO2/PET remain unchanged over 1000 bending cycles. The measured driving voltage and response time values open great potential of TiO2/Ag/TiO2/PET for integration into next-generation ITO-free flexible and stretchable devices.

Molecular Characterization of Verbascum anisophyllum (Scrophulariaceae) Genetic Resources Through Inter-Simple Sequence Repeat (ISSR) Markers.

Verbascum (Mullein) flowers are highly valued as natural remedy for various respiratory diseases. Verbascum anisophyllum Murb. is a Balkan endemic, protected by law and included in the Bulgarian Red Data Book as "Critically Endangered". Thus, a strict conservation policy and a reliable evaluation of its genetic resources are required, considering its narrow distribution range and the increasing risk from destruction of its habitats. Here, we used Inter-simple sequence repeat (ISSR) markers to characterize the genetic diversity and to assess the genetic differentiation between the existing populations of VerbascUM anisophyllum in Bulgaria. The level of genetic diversity found herein clearly indicates a long-term potential for adaptability of this endangered plant. Our findings provide important knowledge of population genetic structure of this species, thus representing a strategy for its efficient conservation and utilization.

Effects of a recombinant gene expression on ColE1-like plasmid segregation in Escherichia coli.

BACKGROUND: Segregation of expression plasmids leads to loss of recombinant DNA from transformed bacterial cells due to the irregular distribution of plasmids between the daughter cells during cell division. Under non-selective conditions this segregational instability results in a heterogeneous population of cells, where the non-productive plasmid-free cells overgrow the plasmid-bearing cells thus decreasing the yield of recombinant protein. Amongst the factors affecting segregational plasmid instability are: the plasmid design, plasmid copy-number, host cell genotype, fermentation conditions etc. This study aims to investigate the influence of transcription and translation on the segregation of recombinant plasmids designed for constitutive gene expression in Escherichia coli LE392 at glucose-limited continuous cultivation. To this end a series of pBR322-based plasmids carrying a synthetic human interferon-gamma (hIFNγ) gene placed under the control of different regulatory elements (promoter and ribosome-binding sites) were used as a model. RESULTS: Bacterial growth and product formation kinetics of transformed E. coli LE392 cells cultivated continuously were described by a structured kinetic model proposed by Lee et al. (1985). The obtained results demonstrated that both transcription and translation efficiency strongly affected plasmid segregation. The segregation of plasmid having a deleted promoter did not exceed 5% after 190 h of cultivation. The observed high plasmid stability was not related with an increase in the plasmid copy-number. A reverse correlation between the yield of recombinant protein (as modulated by using different ribosome binding sites) and segregational plasmid stability (determined by the above model) was also observed. CONCLUSIONS: Switching-off transcription of the hIFNγ gene has a stabilising effect on ColE1-like plasmids against segregation, which is not associated with an increase in the plasmid copy-number. The increased constitutive gene expression has a negative effect on segregational plasmid stability. A kinetic model proposed by Lee et al. (1985) was appropriate for description of E. coli cell growth and recombinant product formation in chemostat cultivations.

Purification and refolding of recombinant human interferon-gamma in urea-ammonium chloride solution.

A method for purification and refolding of recombinant human interferon-gamma (hIFNgamma) from inclusion bodies is described. It includes the following steps: (i) solubilization of inclusion bodies in 7.4 M guanidinium hydrochloride; (ii) purification of the denatured hIFNgamma by hydrophobic chromatography on Octyl-Sepharose column (one step elution with 6 M urea/1 M ammonium chloride); (iii) refolding of the partly purified protein in 0.75 M urea, 20 mM Tris-HCl, pH 8.2; (iv) purification of the refolded protein by CM-Sepharose chromatography. The protein thus obtained is characterized by the following general parameters: yield 1.0 mg/g wet cell mass; purity >99%; specific activity 2x10(8)IU/mg; stability - more than two years as a lyophilized powder and more than two months in solution at 4 degrees C.

Liquid chromatography method for simultaneous analysis of amino acids and biogenic amines in biological fluids with simultaneous gradient of pH and acetonitrile.

A liquid chromatography method for simultaneous analysis of amino acids, polyamines, catecholeamines and metanephrines in human body fluids after derivatization with 9-fluorenylmethyloxycarbonyl chloride was developed. The chromatographic behavior of analytes at different pH of mobile phase was studied. Successful baseline resolution of all analyzed compounds was achieved using simultaneous gradient of pH and organic modifier in reverse phase mode of HPLC within 36 min. The repeatability of the proposed procedure in respect of retention time and peak area, expressed as RSD, ranges from 0.06 to 1.64% and 0.4 to 7.6%, respectively. The method linearity in the range of 1-200 microM for amino acids and in the range of 0.1-20 microM for polyamines, catecholeamines and metanephrines was found to be with correlation coefficients higher than 0.994. The limit of quantification (LOQ) was assessed to be in the range of 2.6-10 pmol for amino acids and 2-4 pmol for polyamines, catecholeamines and metanephrines.

Simultaneous analysis of amino acid and biogenic polyamines by high-performance liquid chromatography after pre-column derivatization with N-(9-fluorenylmethoxycarbonyloxy)succinimide.

A high-performance liquid chromatography method for the simultaneous analysis of amino acids and biogenic polyamines, using a new procedure for pre-column derivatization of amino groups with N-(9-fluorenylmethoxycarbonyloxy)succinimide is described. The separation of 20 amino acids and 4 biogenic polyamines was achieved within 32 min on a sequence of three short (50 mm) reversed-phase C18, 5 microm columns by elution buffers based on dibutylamine phosphate. The method linearity, calculated for each amino acid and polyamine, has a correlation coefficient higher than 0.991, in concentrations ranging from 0.2 to 50 microM, except for spermine and methionine, where the correlation coefficients were r = 0.984 and r = 0.979, respectively. The stability of derivatives in acidified samples at 4 degrees C and room temperature was demonstrated. The limit of quantitation was estimated to be around 50 pM in 50 microl sample injection. The repeatability of the method, expressed as R.S.D., ranged from 1.1 to 6.7%. The presented method was applied for the quantitation of amino acid and polyamine contents in beer, wine, and cell culture samples, using 2-aminoheptanoic acid or 1,7-diaminoheptane as internal standard.