CARBON-14 LABELING AND BIOLOGICAL ACTIVITY OF THE TUMOR-LOCALIZING DERIVATIVE OF HEMATOPORPHYRIN

Abstract— Carbon-14-labeled hematoporphyrin ([¹⁴C]HP) was synthesized by two methods, (i) Using an in vitro avian whole-blood system, [¹⁴C]protoheme was obtained biosynthetically by incorporating [⁴C]aminolevulinic acid into the porphyrin ring structure. Subsequently, the [¹⁴C]protoheme was converted to [⁴C]HP by standard procedures, (ii) By adopting several well-characterized chemical reactions, deuteroporphyrin was treated with [¹⁴C]acetyl chloride, giving [¹⁴C]diacetyl deuteroporphy-rin which was readily reduced and hydrolyzed to [¹⁴C]HP (with thecarbon–14 label on the hydroxyethyl side-chains). These two methods are simple and afford good yields of [¹⁴C]HP with moderate to high specific activities. The [¹⁴C]HP was then treated with acetic acid/sulfuric acid followed by sodium hydroxide to give [¹⁴C]HPD. Upon gel- and ultra-filtration, the [¹⁴C]HPD was enriched in the so-called tumor-localizing fraction of HPD, giving [¹⁴C]PII with specific activities of 0.4 Ci/mol (biosynthesis) and 10 Ci/mol (chemical synthesis). These [¹⁴C]PII preparations were equivalent with respect to chromatographic and spectrophotometric characteristics, as well as tumoricidal photodynamic activity in the DBA/2 Ha-DD mouse: SMT-F tumor system, to the unlabeled commercial product Photofrin^? II. The distribution of [¹⁴C]PII in mouse tissues was in close agreement to that previously reported, after adjustment for dose, for [¹⁴C]HPD biosynthetically labeled in vivo (Gomer and Dougherty, 1979), as well as for Photofrin^? II, where tissue levels were determined spectrophotometrically after extraction (Dougherty and Mang, unpublished).     

Graphene as membrane for encapsulation of yeast cells: protective and electrically conducting

Graphene sheets (chemically reduced), a high modulus and high thermal and electrically conductive material are coupled with yeast cells to form an encapsulating inorganic functional layer. The coupling of the high modulus sheets with the cells increases their stability to osmotic stresses. The sheets also allow the direct visualization of the cells in an electron microscope.     

One-pot efficient synthesis of dimeric, trimeric, and tetrameric BODIPY dyes for panchromatic absorption

One-pot Knoevenagel self-condensation reaction of β-formyl BODIPY dye bearing a formyl group at 2-position offered dimeric, trimeric and tetrameric BODIPY dyes containing a formyl capping end group, exhibiting panchromatic absorption.     

Enantioselective syntheses of (+)-sertraline and (+)-indatraline using lithiation/borylation-protodeboronation methodology

The lithiation/borylation-protodeboronation of a homoallyl carbamate was applied to the synthesis of (+)-sertraline and (+)-indatraline. Due to the presence of the alkene, significant modifications of the methodology were required (use of 12-crown-4, TMSCl, H(2)O), or a solvent switch to CHCl(3), to achieve high yields and high selectivities.     

Development and validation of a highly sensitive LC-MS/MS method for simultaneous quantitation of acetyl-CoA and malonyl-CoA in animal tissues

A highly sensitive and specific LC‐MS/MS method was developed for simultaneous estimation of acetyl co‐enzyme A (ACoA) and malonyl co‐enzyme A (MCoA) in surrogate matrix using n‐propionyl co‐enzyme A as an internal standard (IS). LC‐MS/MS was operated under the multiple reaction‐monitoring mode using the electrospray ionization technique. Simple acidification followed by dilution using an assay buffer process was used to extract ACoA, MCoA and IS from surrogate matrix and tissue samples. The total run time was 3 min and the elution of both analytes (ACoA, MCoA) and IS occurred at 1.28 min; this was achieved with a mobile phase consisting of 5 mM ammonium formate (pH 7.5)–acetonitrile (30:70, v/v) delivered at a flow rate of 1 mL/min on a monolithic RP‐18e column. A linear response function was established for the range of concentrations 1.09–2187 and 1.09–2193 ng/mL for ACoA and MCoA, respectively. The intra‐ and inter‐day precision values for ACoA and MCoA met the acceptance as per FDA guidelines. ACoA and MCoA were stable in a battery of stability studies viz. bench‐top, auto‐sampler and long‐term. The developed assay was used to quantitate ACoA and MCoA levels in various tissues of rat. Copyright © 2011 John Wiley & Sons, Ltd.     

Investigation of dielectric properties of newly prepared β-phase polyvinylidene fluoride–barium titanate nanocomposite films

In the present investigation nanocomposite films were prepared by solution casting method with β-phase Polyvinylidene fluoride (PVDF) as a polymer matrix and barium titanate as a filler which was prepared using Ti(IV) triethanolaminato isopropoxide and hydrated barium hydroxide as precursors and tetra methyl ammonium hydroxide (TMAH) as a base. The XRD, FTIR, SEM shows that the fillers in nanocomposites were homogeneous and well dispersed. The dielectric constant and dissipation factors studied in the experimental range of nanocomposites were found to be around 7 and 0.03 respectively which may be very good material to be explored for novel capacitors.     

A critical remark on “Fixed point theorems for occasionally weakly compatible mappings”

In the present paper, we show that under contractive conditions, the existence of a common fixed point and occasional weak compatibility are equivalent conditions. We also show that contractive conditions employed by Jungck and Rhoades [Fixed point theorems for occasionally weakly compatible mappings, Fixed Point Theory 7(2) (2006) 287–296; Fixed Point Theory 9 (2008) 383–384 (erratum)] do not provide a nontrivial setting for the application of occasional weak compatible mappings. Finally, we improve the results of Jungck and Rhoades by employing a proper setting.     

Influence of electrical and optical losses on fundamental solar-cell parameters

Summary We present here an analysis of the dependence of the light-generated current on the current at maximum power in lossy solar cells. that is, cells with both series and shunt resistances present simultaneously — that is, a real cell. It is essentially seen that this dependence is highly sensitive to series resistance. However, for cells with series resistance of the order of 3 Ω, ϖI _g/ϖI _mp=1. We also look at the influence of TiO_x antireflection coatings on the open-circuit voltage and short-circuit current in silicon solar cells.

---

Riassunto Si presenta un'analisi della dipendenza della fotocorrente dalla corrente di massima potenza nelle celle solari quando sono contemporaneamente presenti le resistenze serie e di shunt. Su tale dipendenza influisce molto la resistenza serie. Tuttavia, se questa è dell'ordine di 3 Ω, è ϖI _g/ϖI _mp=1. Si studia anche l'influenza di rivestimenti antiriflettenti di TiO_x sulla tensione di circuito aperto, sulla corrente di circuito aperto e sulla corrente di corto circuito nelle celle di silicio.

---