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An achromatic linear polarization rotator based on a tandem-2ϕ-twisted nematic liquid crystal cell (tandem-2ϕ-TNLC cell, where 2ϕ represents the total twisted angle) is theoretically analyzed and experimentally demonstrated. The tandem-2ϕ-TNLC cell comprises two conventional ϕ-TNLC cells with the required arrangement that the LC director close to the last layer of the first ϕ-TNLC cell should be perpendicular to that close to the first layer of the second ϕ-TNLC cell. With such a simple combination, the TNLC performances are considerably improved. According to the experimental results and theoretical analyses by Jones Calculus, the tandem-2ϕ-TNLC polarization rotator with suitable parameters is achromatic and insensitive to the polarization plane of incident light. Such properties provide these polarization rotators with potential for practical applications. [ABSTRACT FROM AUTHOR]

Abstract  For this study, 68 plum samples were collected from 12 provinces of China. Low molecular weight RNAs were extracted and used for dot-blot, reverse transcription–polymerase chain reaction (RT-PCR), return–polyacrylamide gel electrophoresis, and biological indexing using cucumber. Results showed that 15 out of the 68 plum samples were positive for Hop stunt viroid (HSVd). Four positive samples were selected for cloning and sequence analysis. Results indicated that most HSVd sequences from the plum in China had 1–3 nucleotide changes from the closest HSVd in GenBank. In addition, the sample PB21 (cv. ‘Friar’) collected from Hebei province had one sequence with a 15-nt duplication (named HSVd D-15) at the 244/245 position in the lower central region. By biological indexing, cucumber seedlings, an indicator plant for HSVd, were inoculated with RNAs directly extracted from the original plum source (PB21, cv. ‘Friar’). Nucleotide sequencing analysis of the progeny showed that HSVd, but not HSVd-D15, was recovered from inoculated cucumbers. Although very unlikely, the possibility that this extra sequence was the result of a PCR artifact cannot be completely ruled out. [ABSTRACT FROM AUTHOR]

Fibrodysplasia ossificans progressiva (FOP) is a rare congenital disease with autosomal dominant transmission characterized by the presence of malformations of the big toes and of postnatal progressive heterotopic endochondral osteogenesis. We report the case of 3-year-old girl with dysplasia of the first metatarsal bones and progressive heterotopic ossificans of the right thigh due to previous diphtheria–tetanus–pertussis immunizations and several inappropriate surgical interventions. Direct sequence analysis identified a 617G–A nucleotide mutation in the patient but not in her parents or brother. Pedigree analysis suggests that a de novo mutation in the ACVR1 gene is responsible for the disease in this family. This is the first report of the results of a mutation analysis in a sporadic case of FOP in a Taiwanese patient. [ABSTRACT FROM AUTHOR]

Artificial recombinant receptors may be useful for selectively targeting imaging and therapeutic agents to sites of gene expression. To evaluate this approach, we developed transgenes to express highly on cells a single-chain antibody (scFv) against the hapten 4-ethoxymethylene-2-phenyl-2-oxazoline-5-one (phOx). A phOx enzyme conjugate was created by covalently attaching phOx molecules to polyethylene glycol (PEG)-modified β-glucuronidase. Cells expressing phOx scFv but not control scFv receptors were selectively killed after exposure to β-glucuronidase derivatized with phOx and PEG (phOx-βG-PEG) and a glucuronide prodrug (p-hydroxy aniline mustard β-D-glucuronide, HAMG) of p-hydroxyaniline mustard. Targeted activation of HAMG produced bystander killing of receptor-negative cells in mixed populations containing as few as 10% phOx-receptor-positive cells. Functional phOx scFv receptors were stably expressed on B16-F1 melanoma tumors in vivo. Treatment of mice bearing established phOx-receptor-positive tumors with phOx-βG-PEG and HAMG significantly (P≤.0005) suppressed tumor growth as compared with treatment with βG-PEG and HAMG or prodrug alone. phOx was unstable in the serum, suggesting alternative haptens may be more suitable for in vivo applications. Our results show that therapeutic agents can be targeted to artificial hapten receptors in vitro and in vivo. The expression of artificial receptors on target cells may allow preferential delivery of therapeutic or imaging molecules to sites of transgene expression. [ABSTRACT FROM AUTHOR]