Effect of body hydration on renal function according to renographic findings in healthy children

The background and tasks of occupational health nurses in North Dakota vary considerably. Those entering the field have little or no previous exposure to occupational health nursing and must develop skill through seminars, corporate training or area associates. In most instances, the nurse represents the occupational safety and health program for the firm and must take on additional roles such as safety director or assistant plant manager. In addition, the occupational health nurse performs numerous in-plant medical services ranging from emergency medical care to counseling and education. The occupational health nurse in North Dakota generally does not record family histories, take throat cultures, take routine x-rays, make hospital or home visits nor perform air sampling or noise level measurements.     

An immune complex selective affinity column utilizing site-specific attachment of bovine conglutinin

Established leukemic cell lines have been useful models for studying the biology of leukemia. Analysis of the actions of differentiating agents on leukemic cell lines in vivo has been limited by an inability to unambiguously distinguish host hematopoietic elements from differentiated leukemic cells. In order to identify and quantify leukemic cells during in vivo studies, a derivative of the murine myelomonocytic leukemia cell line WEHI-3B D+, which stably expresses beta-galactosidase, was constructed utilizing retroviral vector gene transfer. This cell line, termed WEHI-3B D+/lacZ 2.8, demonstrated in vitro growth and differentiation properties similar to the parental cell line. WEHI-3B D+/lacZ 2.8 expressed high levels of beta-galactosidase following prolonged in vitro growth and following differentiation in suspension cultures and clonogenic assays. In vivo, WEHI-3B D+/lacZ 2.8 was leukemogenic and high level expression of beta-galactosidase was maintained. Quantification of tissue involvement with WEHI-3B D+/lacZ 2.8 leukemia was performed utilizing staining with the fluorogenic beta-galactosidase substrate fluorescein di-beta-galactoside and fluorescence-activated cell sorting analysis. In vivo differentiation efficiency following granulocyte colony-stimulating factor (G-CSF) administration was determined using a simultaneous nuclear and cytoplasmic staining procedure. Results indicate that treatment of mice inoculated with WEHI-3B D+/lacZ 2.8 cells with G-CSF administration causes detectable but limited differentiation.     

Nurse-midwifery service model in an academic environment

Chiral high performance liquid chromatography was used for the enantiometric separation of leucovorin. The optimal separation conditions recommended after optimizing the mobile phase composition, flow rate, and temperature are described. Achiral reversed-phase chromatographic method was applied for the simultaneous separation of methotrexate and leucovorin in clinical samples. Column-switching system including achiral short pre-column and chiral analytical column based on immobilized bovine serum albumin were used for simultaneous determination of leucovorin and methotrexate patients treated at the National Cancer Institute.     

Modeling of the time-dependency of in vitro drug cytotoxicity and resistance

For potential clinical extrapolation of in vitro findings, it is of interest to relate the measured effect of an anticancer agent to concentration and exposure time. The Hill model (A. V. Hill, J. Physiol., 40: iv-vii, 1910) is commonly used to describe pharmacodynamic (PD) effects, including drug-induced growth inhibition of cancer cells in vitro. The IC(X)n x T = k relationship, in which IC(X) is the concentration of agent required to reduce cell growth by X%, T is the exposure time, and n and k are estimable parameters, was first applied to bacterial disinfectant action and then was successfully used to model anticancer drug potency as a function of exposure time (D. J. Adams, Cancer Res., 49: 6615-6620, 1989). Our goal was to create a new global PD modeling paradigm to facilitate the quantitative assessment of the growth-inhibitory effect of anticancer agents as a function of concentration and exposure time. Wild-type human ovarian A2780 and ileocecal HCT-8 carcinoma cells and sublines that were resistant to cisplatin (A2780/CP3), doxorubicin (A2780/DX5B), and raltitrexed (RTX) (HCT-8/DW2) were exposed to various anticancer agents, cisplatin, doxorubicin, paclitaxel, trimetrexate, RTX, methotrexate, and AG2034, for periods ranging from 1 to 96 h. Cell growth inhibition was measured with the sulforhodamine B protein dye assay. Patterns of time-dependency of drug potency, slope of the concentration-effect curves, and relative degree of resistance were characterized. Empirical mathematical expressions were built into a global concentration-time-effect model. The global PD model was then fit to the concentration-time-effect data with iteratively reweighted nonlinear regression. Under specific treatment conditions, the examination of the slope and the shape of the concentration-effect curves revealed a large heterogeneity in drug response, e.g., shallow concentration-effect curve or double or triple Hill "roller coaster" concentration-effect curve. These patterns, which were observed at intermediate exposure times in parental and resistant cells for paclitaxel and trimetrexate or only in resistant HCT-8/DW2 cells for RTX, methotrexate, and AG2034, revealed mechanistic insights for the former cases but possible methodological artifacts for the latter cases. The comprehensive PD modeling of the cytotoxic effect of anticancer agents showed that it was possible to modulate drug effect, response heterogeneity, and drug resistance by altering the time of exposure to the agents. This approach will be useful for: (a) describing complex concentration-time-effect surfaces; (b) refining biological interpretations of data; (c) providing insights on mechanisms of drug action and resistance; and (d) generating leads for clinical use of anticancer drugs.     

On security of wireless sensor networks: a data authentication protocol using digital signature

Guaranteeing end-to-end data security in wireless sensor networks (WSNs) is important and has drawn much attention of researchers over past years. Because an attacker may take control of compromised sensor nodes to inject bogus reports into WSNs, enhancing data authenticity becomes a necessary issue in WSNs. Unlike PCREF (Yang et al. in IEEE Trans Comput 64(1):4–18, 2015) (LEDS, Ren et al. in IEEE Trans Mobile Comput 7(5):585–598, 2008), digital signature rather than message authentication polynomials (message authentication codes) is adopted by our protocol in en-route filtering. Keeping the advantages of clusters in PCREF and overcoming the drawbacks in LEDS, an enhanced and efficient cluster-based security protocol is proposed in this paper. The proposed protocol can guarantee end-to-end data authentication with the aid of digital signature and exhibits its effectiveness and efficiency through security analysis and performance analysis. Our analytical results show that the proposed protocol significantly outperforms the closely related protocols in the literature in term of security strength and protocol overhead.