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Study design: Systematic review. Objectives: The overall incidence of intramedullary spinal cord tumors (IMSCT) remains low and clinical trials or standardized treatment strategies are missing. Therefore, multiple animal-based xenograft models (AXM) have been developed to foster preclinical research efforts on IMSCT. We constructed a systematic literature review to summarize and compare all AXM for IMSCT, published until April 16, 2018. Methods: The review was conducted using 4 independent research databases following the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. Studies were included, if they reported on surgical transplantation of tumor cells or tumor tissue to the spinal cord. Methodological study quality was assessed according to the SYRCLE (systematic review center for laboratory animal experimentation) risk of Bias tool. Results: Systematic search yielded 20 publications dealing with AXM for IMSCT. In summary, 4 tumor entities were analyzed in 23 experiments using ~337 animals, mainly investigating glioblastoma or gliosarcoma biology. Studies varied regarding the use of engrafted animals, surgical techniques and tumor burden. Most commonly authors used heterotopic, transdural injection of immortalized brain tumor cell lines (1 × 105in 5 µl) into the thoracic spinal cord of immunocompromised rats. Quality assessment demonstrated an unclear risk of bias in most cases. Conclusion: Although different AXM for IMSCT have been described so far, one rat model is technically feasible, enables robust experiments and demonstrates reproducible results. However, there is a need for new AXM using orthotopic engraftment of patient-derived tumor cells and for genetically engineered animal models.

Rice (Oryza sativaL.) milling yield is a key export and domestic grain quality trait whose genetic control is poorly understood. To identify genomic regions influencing grain quality, quantitative trait locus (QTL) mapping was performed for quality‐related traits including head‐rice yield (HR) in 205 recombinant inbred lines (RILs) derived from a cross of L‐204, a high‐HR long‐grain cultivar, with 01Y110, a low‐HR advanced breeding line with high yield potential in the temperate U.S. rice‐growing region. In replicated trials planted in California during 2007–2008, four QTLs carrying the HR‐increasing allele from L204 and three from 01Y110 were consistently expressed. Multi‐QTL models accounted for 30% of genetic variation for HR and up to 58% for other quality‐related traits. Measures of kernel damage, though correlated with HR, were poor predictors of HR. Heading time, kernel dimension, apparent amylose content, and other highly heritable traits showed no correlation with HR. Stable QTLs for HR are likely to be revealed best by multienvironment experiments employing larger population sizes or more direct measurement of kernel structure and development traits involved in kernel breakage.

Abstract: Abundant, codominant simple sequence repeats (SSRs) markers can be used for constructing genetic linkage maps and in marker-assisted breeding programs. Enrichment methods for SSR motifs were optimized with the ultimate aim of developing numerous loci in flowering dogwood (C. florida L.) genome. Small insert libraries using four motifs (GT, CT, TGG, and AAC) were constructed with C. florida ‘Cherokee Brave’ deoxyribonucleic acid (DNA). Colony polymerase chain reaction (PCR) of 2,208 selected clones with three primers we reported previously indicated that 47% or 1,034 of the clones harbored one of the four targeted SSR motifs. Sequencing the putative positive clones confirmed that nearly 99% (1,021 of 1,034) of them contained the desired motifs. Of the 871 unique SSR loci, 617 were dinucleotide repeats (70.8%), and 254 were trinucleotide or longer repeats (29.2%). In total, 379 SSR loci had perfect structure, 237 had interrupted, and 255 had compound structure. Primer pairs were designed from 351 unique sequences. The ability of the 351 SSR primer pairs to amplify specific loci was evaluated with genomic DNA of ‘Appalachian Spring’ and ‘Cherokee Brave’. Of these primers, 311 successfully amplified product(s) with ‘Cherokee Brave’ DNA, 21 produced weak or faint products, and 19 did not amplify any products. Additionally, 218 of the 311 primers pairs revealed polymorphisms between the two cultivars, and 20 out of 218 primers detected an average of 13.7 alleles from 38 selected Cornus species and hybrids. These SSR loci constitute a valuable resource of ideal markers for both genetic linkage mapping and gene tagging of flowering dogwood.

Aflatoxins are toxic and carcinogenic polyketide metabolites produced by fungal species, including Aspergillus flavusand A. parasiticus. The biosynthesis of aflatoxins is modulated by many environmental factors, including the availability of a carbon source. The gene expression profile of A. parasiticuswas evaluated during a shift from a medium with low concentration of simple sugars, yeast extract (YE), to a similar medium with sucrose, yeast extract sucrose (YES). Gene expression and aflatoxins (B1, B2, G1, and G2) were quantified from fungal mycelia harvested pre- and post-shifting. When compared with YE media, YES caused temporary reduction of the aflatoxin levels detected at 3-h post-shifting and they remained low well past 12 h post-shift. Aflatoxin levels did not exceed the levels in YE until 24 h post-shift, at which time point a tenfold increase was observed over YE. Microarray analysis comparing the RNA samples from the 48-h YE culture to the YES samples identified a total of 2120 genes that were expressed across all experiments, including most of the aflatoxin biosynthesis genes. One-way analysis of variance (ANOVA) identified 56 genes that were expressed with significant variation across all time points. Three genes responsible for converting norsolorinic acid to averantin were identified among these significantly expressed genes. The potential involvement of these genes in the regulation of aflatoxin biosynthesis is discussed.

Medicinal plants have become extremely popular in the United States as botanical supplements, herbal medicines and sources of lead compounds for pharmaceutical development. It is estimated that in 1997 Americans used or consumed 5.1 billon dollars worth of herbal medicines. For the protection of consumers, authentication of medicinal plants is a critical issue. Ideally, authentication should occur from the harvesting of the plant material to the final product. Unfortunately there is no single or superior method to assure 100 percent authentication during the entire process, but the goal can be achieved through the application of a variety of different methodologies. The whole process starts with good voucher specimens that act as reference material and to prove chain of custody. Macroscopic and microscopic examinations can be used as rapid and inexpensive identification techniques. Chemical analysis is by far the best method for the detection of contaminants and can be an excellent method for plant identification. Each of these methodologies has limitations and more analytical methods are needed to assist in the authentication process. Molecular biology offers an assortment of techniques that can be very useful for authentication of medicinal plants. This review covers various aspects of authentication methods, with special emphasis on molecular biology techniques.

Recentin vitrostudies have shown that the periventricular subependymal zone (SEZ) of the rodent brain is capable ofde novogeneration of neurons and glia. There is less information available on neurogenesis in the adult human brain, and no study has shown the clonal generation of neurons and glia fromin vitro-generated “neurospheres.” Here we describe the isolation of proliferative stem/progenitor cells within neurospheres from two different regions, the SEZ and the hippocampus, from surgical biopsy specimens of adult (24–57 years) human brain. Using light and electron microscopy; immunocytochemistry for a variety of neuronal, glial, and developmental (including extracellular matrix; ECM) markers; and the reverse transcriptase polymerase chain reaction to demonstrate different gene transcripts found in neurospheres, it is shown that the adult human brain harbors a complex population of stem/progenitor cells that can generate neuronal and glial progeny under particularin vitrogrowth conditions. These methods also show that these neurospheres contain both neurons and glia and demonstrate regional similarities at the mRNA level, indicating common stem/progenitor cell types within two different neurogenic regions of the adult human brain. In addition to the synthesis of developmentally regulated molecules such as the ECM protein tenascin-C, a variety of other genes (e.g.,Pax 6) and proteins (e.g., Bcl-2) involved in cell survival and differentiation are expressed by adult human brain neurospheres.

The structure and function of several C1 alleles have been investigated molecularly and the importance of C1 promoter sequences for gene expression was studied using transient transformation assays. The C1 mutants analyzed were the overexpressing allele C1-S, the light-inducible allele c1-p, the null recessive allele c1-n, and the Ds element-induced allele c1-m1. Nucleotide sequence analysis of the alleles revealed a number of differences, predominantly located at the 3' end of the gene. The promoter sequences of the C1 alleles investigated so far (including wild-type and the dominant inhibitor C1-I allele) are almost identical except for two short footprint-like sequences (Box I and Box 11) close to the putative CAAT box. Northern blot experiments and transient expression in particle gun experiments indicate that these sequences may be correlated with the different expression patterns of the alleles in the aleurone of maturing and germinating kernels.

Two receptor element alleles (vp-rcy and bz-rcy) that respond to the trans-active element (Cy) controlling Mutator activity were used to analyze the strength of trans-active signals from Cy elements derived from a Mutator active line. Evidence is presented that the Mutator population tested consists mainly of a class of weak Cy elements designated as Cy:Mu. When Cy:Mu element are present in only a few copies, the strength of the combined transposition signal is weak. It is only when these active elements have a high copy number that the overall transposition signal is sufficiently strong enough to elicit a high frequency of transposition events. This study seeks to investigate the nature of the trans-active signal from Cy:Mu elements. The implication of these results for molecular studies is discussed.

Zusammenfassung Nach einleitenden theoretischen Erläuterungen über das Wesen der kieferorthopädischen Behandlungsmethode nach Balters werden die Formen des Bionators mit einigen Modifikationsmöglichkeiten beschrieben.

Zusammenfassung Im Rahmen der jährlich stattfindenden klinischen Untersuchungen Musterungspflichtiger wurden die Gebißverhältnisse der Jahrgänge 1951/52 bei drei Gruppen 17- bis 18jähriger Jugendlicher eruiert und statistisch ausgewertet. Studenten wiesen eine höhere Kariesanfälligkeit auf als die übrigen Jugendlichen der Land- und Stadtbevölkerung. Die Häufigkeit der Parodontalerkrankungen und der Dysgnathien nimmt in der Reihenfolge Land-, Stadtjugend und Studenten ab. Ohne wesentliche Abweichung zwischen den drei untersuchten Gruppen beträgt die Rate der naturgesunden Gebisse durchschnittlich 2,02%. Die Beziehungen zwischen den Merkmalen und Gruppen haben wir nach allgemeinstomatologischen und kieferorthopädischen Gesichtspunkten analysiert.