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Background: The survival of patients with high-risk, refractory, relapsed, or metastatic solid tumors remains dismal. A poly(ADP-ribose) polymerase (PARP) inhibitor could be effective for the treatment of pediatric solid tumors with defective homologous recombination., Methods: This open-label, multicenter phase 1 clinical trial evaluated the safety, tolerability, and efficacy of olaparib, a PARP inhibitor, in pediatric patients with refractory solid tumors to recommend a dose for Phase 2 trials. Olaparib (62.5, 125, and 187.5 mg/m 2 twice daily) was administered orally every day (1 cycle = 28 days) using a standard 3 + 3 dose-escalation design. Patients aged 3-18 years with recurrent pediatric solid tumors were eligible. Pharmacokinetic and pharmacodynamic analyses were performed., Results: Fifteen patients were enrolled and received olaparib monotherapy, which was well tolerated. The recommended phase 2 dose for daily administration was 187.5 mg/m 2 twice daily. Pharmacokinetics were dose proportional. The area under the concentration-time curve from 0 to 12 h and the peak plasma concentration for 187.5 mg/m 2 twice daily in children were comparable to previous data obtained in a 200-mg, twice-daily cohort and lower than those in the 300-mg twice-daily cohort in adults. Pharmacodynamic studies demonstrated substantial inhibition of PARP activity. Two partial responses were observed in patients with Wilms tumor and neuroblastoma., Conclusions: This report is the first clinical trial to describe the use of a PARP inhibitor as monotherapy in children. Olaparib was well tolerated, with preliminary antitumor responses observed in DNA damage response-defective pediatric tumors., Lay Summary: This Phase 1 trial evaluated the efficacy and safety of olaparib in patients with refractory childhood solid tumors. Olaparib was well tolerated, achieving objective response in 2/15 patients. The DNA damage response was attenuated in nearly one-half of advanced neuroblastoma patients, demonstrating the utility of the PARP inhibitor. The results support further investigation of olaparib as a new treatment for DNA damage-response or repair-defective pediatric cancers., (© 2022 American Cancer Society.)

We have developed a novel technique for constructing microarrays of transfected mammalian cells on or in extracellular matrix (ECM) hydrogels by transfer printing from patterned poly(ethylene glycol) (PEG)-oleyl surfaces. A mixed solution of small interfering RNA (siRNA) and a transfection reagent was spotted on PEG-oleyl-coated glass slides using an ink-jet printer, and the cells were then transiently immobilized on the patterned transfection mixtures. After overlaying an ECM hydrogel sheet onto the immobilized cells, the cells sandwiched between the glass slide and the hydrogel sheet were incubated at 37°C for simultaneous transfection of siRNA into cells and adhesion of cells to the hydrogel sheet. Transfer of the adhered, transfected cells was completed by peeling off the hydrogel sheet. The knockdown of a model gene in the transferred cell microarray by the transfected siRNA was successfully confirmed. Transfected cell microarrays were also embedded within three-dimensional ECM hydrogels. In the three-dimensional hydrogel, the inhibition effect of siRNA on cancer cell invasion was evaluated by quantifying the size of cell clusters on the microarrays. These results indicate that transfection of cell microarrays on or in a biological matrix is a promising technique for high-throughput screening of disease-related genes by direct observation of cellular phenomena in a physiologically relevant environment., (© 2013 Wiley Periodicals, Inc.)

Development of the techniques for fabricating three-dimensional tissues still poses significant challenges for tissue engineering. We used hydrogels obtained from phenol-substituted amylopectin (AP-Ph) as templates for preparing multicellular spherical tissues (MSTs) and endothelialized curved tubular structures in type I collagen gel. AP-Ph hydrogel microparticles of diameter 200 µm and fibers of diameter 500 µm disappeared within hours of soaking in a serum-containing medium. HeLa cells and human endothelial cells were enclosed in the microparticles and hydrogel fibers, respectively, and then embedded in Ca-alginate microcapsules or the collagen gel. The enclosed cells were released in cavities formed by hydrogel degradation in the serum-containing medium. The released HeLa cells in the spherical cavities grew and formed MSTs, eventually filling the cavities. The spherical tissues were easily harvested by liquefying the Ca-alginate hydrogel microcapsule membrane by chelation using sodium citrate. The released endothelial cells grew on the tubular cavity surfaces and formed tubular structures. An endothelial cell network was formed by cell migration into the collagen gel. These results demonstrate the potential of serum-degradable AP-Ph hydrogels in constructing three-dimensional tissues., (Copyright © 2012 Wiley Periodicals, Inc.)

Background and Purpose: Glutamate excitotoxicity may be involved in ischaemic injury to the CNS and some neurodegenerative diseases, such as Alzheimer's disease. Donepezil, an acetylcholinesterase (AChE) inhibitor, exerts neuroprotective effects. Here we demonstrated a novel mechanism underlying the neuroprotection induced by donepezil., Experimental Approach: Cell damage in primary rat neuron cultures was quantified by lactate dehydrogenase release. Morphological changes associated with neuroprotective effects of nicotine and AChE inhibitors were assessed by immunostaining. Cell surface levels of the glutamate receptor sub-units, NR1 and NR2A, were analyzed using biotinylation. Immunoblot was used to measure protein levels of cleaved caspase-3, total NR1, total NR2A and phosphorylated NR1. Immunoprecipitation was used to measure association of NR1 with the post-synaptic protein, PSD-95. Intracellular Ca(2+) concentrations were measured with fura 2-acetoxymethylester. Caspase 3-like activity was measured using enzyme substrate, 7-amino-4-methylcoumarin (AMC)-DEVD., Key Results: Levels of NR1, a core subunit of the NMDA receptor, on the cell surface were significantly reduced by donepezil. In addition, glutamate-mediated Ca(2+) entry was significantly attenuated by donepezil. Methyllycaconitine, an inhibitor of alpha7 nicotinic acetylcholine receptors (nAChR), inhibited the donepezil-induced attenuation of glutamate-mediated Ca(2+) entry. LY294002, a phosphatidyl inositol 3-kinase (PI3K) inhibitor, had no effect on attenuation of glutamate-mediated Ca(2+) entry induced by donepezil., Conclusions and Implications: Decreased glutamate toxicity through down-regulation of NMDA receptors, following stimulation of alpha7 nAChRs, could be another mechanism underlying neuroprotection by donepezil, in addition to up-regulating the PI3K-Akt cascade or defensive system.

We report the case of a 32-year-old patient who presented with catatonic stupor during the course of acute aseptic encephalitis involving the right frontotemporal area. Flumazenil-PET performed during the stupor indicated decreased benzodiazepine receptor binding in the right frontotemporal area where glucose metabolism was preserved as revealed by FDG-PET. An injection of diazepam immediately ameliorated catatonic symptoms and reduced widespread high amplitude slow EEG activities with right frontotemporal predominance. Compared with a SPECT study performed a week earlier, there was no abnormal right-sided anteriorly predominant cerebral hyperperfusion after injection of diazepam. While neither flumazenil- nor FDG-PET could be repeated, and with the caveat that generalized convulsions occurred initially and epilepsia partialis continua was present for two weeks starting on the 23rd day after illness onset, these findings suggest that in our case the presentation with catatonic stupor may be related to impairment of the cortical GABAergic inhibitory system.

Occipital neuralgia is a pain syndrome which may usually be induced by spasms of the cervical muscles or trauma to the greater or lesser occipital nerves. We report a patient with occipital neuralgia followed by facial herpes lesion. A 74-year-old male experienced sudden-onset severe headache in the occipital area. The pain was localized to the distribution of the right side of the greater occipital nerve, and palpation of the right greater occipital nerve reproduces the pain. He was diagnosed with occipital neuralgia according to ICHD-II criteria. A few days later, the occipital pain was followed by reddening of the skin and the appearance, of varying size, of vesicles on the right side of his face (the maxillary nerve and the mandibular nerve region). This was diagnosed as herpes zoster. This case represents a combination of facial herpes lesions and pain in the C2 and C3 regions. The pain syndromes can be confusing, and the classic herpes zoster infection should be considered even when no skin lesions are established.