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Background: The inhibitory effects of N-(4-hydroxyphenyl)-retinamide (4HPR) on tumorigenesis and tumor growth may result from its ability to induce apoptosis (programmed cell death). Since antioxidants inhibit 4HPR-induced apoptosis, experiments were planned to determine whether the levels of reactive oxygen species increase in cells undergoing apoptosis after exposure to 4HPR. Methods: Cells of the human cervical carcinoma cell line C33A and normal human cervical epithelial cells were treated with 4HPR and analyzed for survival, induction of apoptosis, generation of reactive oxygen species, and expression of the apoptosis-related proteins Bcl-2 and Bax. Results: Treatment with 4HPR decreased C33A cell number by inducing apoptosis in a time- and dose-dependent fashion. DNA fragmentation typical of apoptosis was observed in cells exposed to 4HPR at concentrations of 3 [mu]M or higher for 6-24 hours. The generation of reactive oxygen species was enhanced by 1.85-fold to 4.5-fold after a 1.5-hour treatment with 0.4-10 [mu]M 4HPR. Pyrrolidine dithiocarbamate, an oxygen radical scavenger, suppressed the rate of generation of reactive oxygen species and inhibited 4HPR-induced apoptosis. 4HPR failed to modulate cellular levels of the Bcl-2 and Bax proteins. N-(4-Methoxyphenyl)-retinamide, the major 4HPR metabolite, and several other retinoids that bind to nuclear retinoic acid receptors or retinoid X receptors failed to enhance the generation of reactive oxygen species and to induce apoptosis. 4HPR was much less effective in generating reactive oxygen species and in inducing apoptosis in normal human cervical epithelial cells than in C33A cervical carcinoma cells. Conclusions: Enhancement of the generation of reactive oxygen species may be involved in apoptotic pathway induction by 4HPR. [J Natl Cancer Inst 1997;89:1191-8]

The development of protein-polymer complexes using protein cages is garnering attention as a strategy to overcome challenges that relate to immunogenicity and protease degradation. We propose the use of thermoresponsive polymers such as poly(N-isopropylacrylamide) (PNIPAM) to form ferritin-polymer complexes through non-covalent interactions. Ferritin is observed to be released from the complexes after 1–2 days incubation at 37 °C.The formation of Ferritin-PNIPAM complexes has been achieved by the introduction of PNIPAM binding peptides to ferritin which results in non-covalent interactions with PNIPAM. Electron microscopy characterization confirms the formation of the complexes. Temperature-induced/phase-transition-mediated protein release demonstrates the potential applications of the complexes as a protein delivery platform.

The adult cerebral cortex can adapt to environmental change. Using monocular deprivation as a paradigm, we find that rapid experience-dependent plasticity exists even in the mature primary visual cortex. However, adult cortical plasticity differs from developmental plasticity in two important ways. First, the effect of adult, but not juvenile monocular deprivation is strongly suppressed by administration of barbiturate just prior to recording visual evoked potentials, suggesting that the effect of adult experience can be inactivated acutely. Second, the effect of deprivation is less persistent over time in adults than in juveniles. This correlates with the known decline in CREB function during maturation of the visual cortex. To compensate for this decline in CREB function, we expressed persistently active VP16-CREB and find that it causes adult plasticity to become persistent. These results suggest that in development and adulthood, the regulation of a trans-synaptic signaling pathway controls the adaptive potential of cortical circuits.

The mechanism by which cancer cells become resistant to cis-Diamminedichloroplatinum (II) (cDDP) is not completely understood. To investigate the molecular markers involved in the cDDP resistance, we compared the gene expression profiles between a head and neck squamous cell carcinoma (HNSCC) line sensitive to cDDP and its cDDP-resistant variant. Both a fluorescent differential display and a cDNA microarray analysis were applied to distinguish the gene profiles between KB, a human HNSCC line, and its cDDP-resistant variant (KB/cDDP). These results were confirmed by Northern blot analysis. One up-regulated gene, glycoprotein hormone α-subunit, and two down-regulated genes coding membrane proteins, human folate receptor and tumor-associated antigen L6, were identified in KB/cDDP cells. Our findings suggest that development of the cDDP-resistant phenotype is accompanied by alternations of gene expression including a glycoprotein hormone and membrane proteins. These gene products could be new molecular markers for resistance to cDDP. © 2003 Wiley Periodicals, Inc. Head Neck 25: 187–193, 2003

Fibroblast growth factor (FGF)-1 modulates various brain functions, such as the hypothalamic control of feeding. In the rat, we examined the effect of intracerebroventricularly infused FGF-1 on the hypothalamic expression of tenascin-C, a selective mediator of neuron-glial interaction. In situhybridization revealed little tenascin-C mRNA expression in control brains, but greatly increased expression in ependymal cells around the third ventricle in the FGF-1-infused rats. Reverse transcription-linked PCR analysis of hypothalamic mRNA revealed an FGF-1-induced expression not of the shortest isoform of tenascin-C, but of the long isoforms (with additional fibronectin type III-domain insertions). Quantitative analysis by real time PCR revealed that this induction was transient and dose-dependent. Specific modulation of hypothalamic neuron–glial interactions by tenascin-C may mediate FGF-1-induced feeding suppression.

We detected in the brain and then cloned two novel, short forms of human and mouse fibroblast growth factor (FGF)-5 mRNA, which were designated human FGF-5S (hFGF-5S) and mouse FGF-5S (mFGF-5S), respectively. Genomic analysis indicated that mFGF-5S and authentic mFGF-5 mRNAs were transcribed from a single gene; hFGF-5S and mFGF-5S mRNAs were generated by excluding the second exon of the respective FGF-5 genes, and the alternatively spliced mRNAs encoded for 123- and 121-amino acid proteins, respectively. Indeed, a neuron-like cell line expressing mFGF-5S mRNA secreted a protein of the expected size and with FGF-5 antigenicity. In PC12 cells, expression of hFGF-5 or exposure to hFGF-5 protein induced differentiation. Neither expression of hFGF-5S, alone, nor co-expression of hFGF-5S with hFGF-5 induced significant differentiation. At high concentrations, hFGF-5S protein partially antagonized FGF-5 activity, whereas by itself, hFGF-5S exerted very weak neurotrophic activity. hFGF-5S protein binds to FGF receptor (FGFR)-1 on PC12 transfectants and partially inhibits hFGF-5-induced tyrosine phosphorylation of FGFR-1 and an FGFR substrate, but it also induces phosphorylation by itself. These results suggest that FGF-5S is a naturally expressed partial agonist/antagonist of FGF-5 neurotrophic activity in the brain and that its effects are exerted in part at the level of the receptor.

Clinical data indicate that the recurring herpes simplex virus (HSV) from oro‐labial lesions is HSV subtype 1 and that the virus from genital lesions is HSV‐2. This suggests that HSV‐1 and HSV‐2 reside in latent forms in the trigeminal ganglia and sacral ganglia, respectively. However, the distribution of latent HSV‐1 and HSV‐2 infections in human spinal ganglia has not been fully examined. This report concerns the application of polymerase chain reaction (PCR) and in situ hybridization (ISH) to such a study. By using PCR and employing the respective primers, HSV‐1 and HSV‐2 DNAs were detected in 207 of 524 samples from 262 spinal ganglia (from the cervical to the sacral ganglia) examined on both sides. The percentages of HSV‐1 and HSV‐2 detected in a given set of ganglia were similar, indicating an absence of site preference. By ISH, few but positive hybridization signals were detected evenly in sacral ganglia sections. The data suggest that regional specificity of recurrent HSV infections is not due to regional distribution of latent virus, but that local host factors may be important for recurrences. J. Med. Virol. 52:136–142, 1997. © 1997 Wiley‐Liss, Inc.

No abstract.

Varicella‐zoster virus (VZV) reactivation without cutaneous vesicles (zoster sine herpete) has been demonstrated in 8 to 25% of patients with acute peripheral facial palsy (APFP) by serological methods. To make an early diagnosis of zoster sine herpete, VZV DNA in oropharyngeal swabs from patients with APFP was examined by the polymerase chain reaction (PCR). VZV DNA was detected in oropharyngeal swabs from 6 of 36 (17%) patients with APFP by PCR. VZV DNA was detected in the oropharyngeal swabs from the six patients at their initial visit (2 to 4 days after the onset of APFP), while the anti‐VZV IgM and IgG antibody titers were not increased significantly. In contrast, VZV DNA was undetectable in the oropharyngeal swabs at the time when the VZV specific antibody response appeared. These results indicate that detection of VZV DNA in oropharyngeal swabs by PCR is more useful than currently available serological assays for the early diagnosis of zoster sine herpete in patients with APFP. J. Med. Virol. 52:316–319, 1997.© 1997 Wiley‐Liss, Inc.

The pollution of water environments is a worldwide concern. Not only marine pollution by plastic litter, including microplastics, but also the spillage of water-soluble synthetic polymers in wastewater have recently gained increasing attention due to their potential risks to soil and water environments. However, conventional methods to identify polymers dissolved in water are laborious and time-consuming. Here, we propose a simple approach to identify synthetic polymers dissolved in water using a peptide-based molecular sensor with a fluorophore unit. Supervised machine learning of multiple fluorescence signals from the sensor, which specifically or nonspecifically interacted with the polymers, was applied for polymer classification as a proof of principle demonstration. Aqueous solutions containing different polymers or multiple polymer species with different mixture ratios were identified successfully. We found that fluorophore-introduced biomolecular sensors have great potential to provide discriminative information regarding water-soluble polymers. Our approach based on the discrimination of multiple optical signals of water-soluble polymers from peptide-based molecular sensors through machine learning will be applicable to next-generation sensing systems for polymers in wastewater or natural environments.

Varicella‐zoster virus (VZV) becomes latent in the sensory ganglia after primary infection and VZV DNA has been found in human trigeminal, thoracic, and geniculate ganglia. In this study, human vestibular and spiral ganglia, which do not receive innervation from the skin, were examined for VZV DNA using the polymerase chain reaction. VZV DNA was detected in 2 of 10 (20%) vestibular ganglia and in 2 of 10 (20%) spiral ganglia from five adults. VZV DNA was undetectable in either type of ganglion from a newborn and from two of the five adults. These two adults were VZV seronegative. The results indicate that VZV becomes latent in several types of sensory ganglion after primary infection and suggest the possibility that reactivation of the virus from the vestibular and spiral ganglia may cause disorders in the labyrinth. J. Med. Virol. 51:214–216, 1997.© 1997 Wiley‐Liss, Inc.

To better understand the pathogenesis of idiopathic sudden hearing loss (ISHL), the possibility of latent virus infection in the spiral ganglion cell was considered. Only few spiral ganglion cells showed positive viral antigen after systemic guinea pig-specific cytomegalovirus (GPCMV) inoculation indicating the absence of hearing loss but the possibility of a subsequent latent infection. By using a modern molecular biological technique we have detected the herpes simplex virus type-1 (HSV-1) DNA in human spiral ganglia. The concept of establishing viral latency in the spiral ganglion cells with periods of reactivation fits with the clinical picture seen in ISHL, even though the mechanism of reactivation still remains unclear.