1,25-Dihydroxyvitamin D3 increases the growth-promoting activity of autocrine epidermal growth factor receptor ligands in keratinocytes

Topical treatment of normal skin with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] or its synthetic analogs results in enhanced keratinocyte proliferation. Autocrine growth factors belonging to the epidermal growth factor (EGF) family play a major role in controlling keratinocyte proliferation. 1,25-(OH)2D3 enhanced the autonomous proliferation of HaCaT human keratinocytes in the absence of exogenous growth factors. Autonomous and 1,25-(OH)2D3-stimulated proliferations were inhibited by a specific inhibitor of EGF receptor (EGFR) tyrosine kinase, an EGFR-neutralizing antibody, heparin, the heparin antagonist hexadimethrine, and the proteoglycan sulfation inhibitor chlorate. These results indicate the involvement of proteoglycan-dependent EGFR ligands. The initial events in EGFR (i.e. ErbB1) mitogenic signal transduction are dimer formation with another ErbB protein and tyrosine cross-phosphorylation. By immunoprecipitation followed by Western blotting we showed that ErbB1/ErbB3 heterodimers are the major mitogenic signaling entity in 1,25-(OH)2D3-stimulated cells. 1,25-(OH)2D3 did not affect the levels of the proteoglycan-dependent EGFR ligands amphiregulin and heparin-binding EGF nor the synthesis of proteoglycans, as assessed by 35S labeling and ion exchange chromatography. 1,25-(OH)2D3 caused a marked increase in the cellular contents of ErbB1, ErbB2, and ErbB3 proteins. The increase in ErbB proteins that mediates signal transduction by EGFR ligands can account for the stimulatory effect of 1,25-(OH)2D3 on autonomous keratinocyte proliferation.     

Bioinspired peptide nanotubes as supercapacitor electrodes

Bioinspired materials offer new routes in nanotechnology. These materials are composed from chemically synthesized biomolecules and inspired by natural biological structures. They are self assembled into highly ordered nanostructures (nanotubes, nanospheres, etc.) from elementary building blocks of biological origin such as peptide and proteins. We developed a new technique of physical vapor deposition of peptide nanotubes (PNT) and applied it to electrochemical energy storage devices—supercapacitors (SC). In this work, aligned and homogenously distributed diphenylalanine PNT have been used to modify carbon electrodes for SC devices. Electrochemical properties of PNT coatings of different density and height, modifying carbon electrodes have been studied. We have found that aligned PNT arrays significantly increase the double layer capacitance of the carbon electrodes. The found enlargement of the PNT-modified electrode capacitance has been ascribed to increasing of usable electrode surface area of the carbon electrodes coated by PNT. We show that the critical factor of the accumulation process of the electrolyte ions at the PNT-modified electrode surface is a wetting process of the PNT nanoscale hydrophilic channels by aqueous electrolyte.     

Reconfigurable manufacturing systems: Principles,design, and future trends

Reconfigurable manufacturing systems (RMSs), which possess the advantages of both dedicated serial lines and flexible manufacturing systems, were introduced in the mid-1990s to address the challenges initiated by globalization. The principal goal of an RMS is to enhance the responsiveness of manufacturing systems to unforeseen changes in product demand. RMSs are costeffective because they boost productivity, and increase the lifetime of the manufacturing system. Because of the many streams in which a product may be produced on an RMS, maintaining product precision in an RMS is a challenge. But the experience with RMS in the last 20 years indicates that product quality can be definitely maintained by inserting in-line inspection stations. In this paper, we formulate the design and operational principles for RMSs, and provide a state-of-the-art review of the design and operations methodologies of RMSs according to these principles. Finally, we propose future research directions, and deliberate on how recent intelligent manufacturing technologies may advance the design and operations of RMSs.     

Complexes of Ir(III)-octaethylporphyrin with peptides as probes for sensing cellular O2

Ir(III)-porphyrins are a relatively new group of phosphorescent dyes that have potential for oxygen sensing and labeling of biomolecules. The requirement of two axial ligands for the Ir(III) ion permits simple linkage of biomolecules by a one-step ligand-exchange reaction, for example, using precursor carbonyl chloride complexes and peptides containing histidine residue(s). Using this approach, we produced three complexes of Ir(III)-octaethylporphyrin with cell-penetrating (Ir1 and Ir2) and tumor-targeting (Ir3) peptides and studied their photophysical properties. All of the complexes were stable and possessed bright, long-decay (unquenched lifetimes exceeding 45 μs) phosphorescence at around 650 nm, with moderate sensitivity to oxygen. The Ir1 and Ir2 complexes showed positive staining of a number of mammalian cell types, thus demonstrating localization similar to endoplasmic reticulum and ATP- and temperature-independent intracellular accumulation (direct translocation mechanism). Their low photo- and cytotoxicity allows intracellular oxygen to be probed.     

Active and passive tobacco smoke exposure: a comparison of maternal and child hair cotinine levels.

The objective of this study was to compare tobacco smoke exposure in mothers and their healthy children less than 3 years old using hair cotinine (HC) levels as an objective long-term measure of exposure. Hair samples were obtained from mother/child pairs recruited from the Columbus Children's Hospital Primary Care Center, and were analyzed by radioimmunoassay to compare HC levels. Mothers were both self-reported smokers and nonsmokers. Contributing and confounding variables were assessed based on questionnaires completed by participants. Exclusion criteria for children were prematurity and presence of chronic cardiopulmonary disease. Hair samples and questionnaires were obtained from 104 mother/child pairs. Child and maternal HC levels were correlated for both self-reported maternal smokers (R2 = .13, p < .013) and self-reported maternal nonsmokers (R2 = .54, p < 001). Child HC levels were higher than maternal HC levels (1.18 ng/mg vs. .78 ng/mg, p < .001). Children of nonsmokers had higher HC levels than their mothers (.77 ng/mg vs. .35 ng/mg, p < .001), while HC levels of smokers and their children were no different (1.91 ng/mg vs. 1.92 ng/mg, p = .978). The relationship between child and maternal HC did not differ by child age, gender, or race. In conclusion, environmental tobacco smoke exposure in young children as reflected by HC is higher than expected based on prior studies of biomarkers and passive tobacco smoke exposure in adult nonsmokers.     

Are there sex differences in neuropsychological functions among patients with schizophrenia?

OBJECTIVE: Studies of sex differences in neuropsychological performance in schizophrenia report inconsistent results, due in part to methodological artifacts. The study presented here was specifically designed to examine sex differences in neuropsychological performance. It was hypothesized that schizophrenic women would exhibit fewer neuropsychological deficits than schizophrenic men and that their performance would be more similar to that of normal women than schizophrenic men's performance would be to that of normal men. METHOD: Thirty-one outpatients with DSM-III-R-defined schizophrenia were systematically sampled from an extensive service network serving a large urban catchment area for seriously mentally ill persons. Twenty-seven normal comparison subjects were matched within sex on the basis of age, parental socioeconomic status, ethnicity, and handedness. An extensive neuropsychological test battery was administered, and multivariate analysis of variance was used to test for the effects of sex and group and sex-by-group interactions. RESULTS: Male patients were significantly impaired across all functions in comparison with normal male subjects and on tests of attention, verbal memory, and executive functions in comparison with female patients. Female patients performed significantly worse than female normal comparison subjects only on tests of attention, executive functions, visual memory, and motor functions. CONCLUSIONS: The findings suggest that women with schizophrenia may be less vulnerable to particular cognitive deficits, especially those involving verbal processing, than schizophrenic men.     

HPLC analysis of the natural scale insect,madder and indigoid dyes

A linear gradient elution method has been applied to the HPLC analysis of plant and scale insect red anthraquinonoid mordant dyes and molluscan blue and red-purple indigoid vat dyes. The method enables the use of the same elution program for the determination of different chemical classes of dyes. In addition, it significantly shortens the retention times of natural anthraquinonoid dyes over those previously published. For the first time a new dye, probably dibromoindirubin, has been detected in the Murex trunculus sea snail. The dye families investigated include the ones most often found on ancient textiles and shards from dyeing vessels in Israel and other regions.     

Imipenem-resistant Ps. aeruginosa bacteraemia in cancer patients: risk factors, clinical features and outcome

Ninety nine patients with 101 bacteraemic episodes due to Ps. aeruginosa (PA) within 6 years were divided into two groups according to their resistance to imipenem-91 due to imipenem sensitive (ISPA) and 10 due to resistant (IRPA). Risk factors, the clinical course and the outcome were evaluated and compared. Acute leukaemia, prolonged neutropenia, previous therapy with amikacin, third generation of cephalosporins, imipenem and prophylaxis by quinolones were significantly more frequently associated with IRPA. Imipenem resistant PA bacteraemia were associated with higher incidence of septic shock (40% vs 19.8%, p < 0.02) and death (33.3%) than ISPA bacteraemias. Since 1992, when first IRPA appeared, the incidence of imipenem resistance increased tenfold, and in 1994, up to 10% of PA causing bloodstream infections in cancer patients in our center were imipenem resistant. (Tab. 3, Ref. 8.).     

Is saliva suitable for therapeutic monitoring of anticonvulsants in children: an evaluation in the routine clinical setting

The acute response of pig skin to treatment with high energy carbon ions (plateau region) at the Gesellschaft für Schwerionenforschung (GSI, Darmstadt, Germany) was compared with changes after 200 kV x-irradiation. Carbon doses isoeffective to the x-ray doses were computed with a recently established model for calculation of the biological effect of heavy ions. Clinical changes and physiological symptoms (blood flow, erythema, trans-epidermal water loss, skin hydration) were scored. The parameters analyzed were maximum and mean values of each symptom during days 24 to 70 after irradiation, and the quantal endpoints for the establishment of dose effect curves were the median values of these. With exception of the maximum change in the red blood cell concentration (p < 0.02) no significant differences could be found in the response to x-rays and RBE-corrected heavy ions. These results indicate that the model is valid for the calculation of biological effects of 12C-ions (plateau region) and may at least for epidermis be applied to treatment planning.     

A self-correcting active pixel sensor using hardware and software correction

Active pixel sensor (APS) CMOS technology reduces the cost and power consumption of digital imaging applications. We present a highly reliable system for the production of high-quality images in harsh environments. The system is based on a fault-tolerant architecture that effectively combines hardware redundancy in the APS cells and software correction techniques.