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Background: Oral lichen planus (OLP) is a chronic inflammatory condition. Clinically, it is characterised by the presence of a white lace-like lesion on the buccal mucosa, tongue, and gingivae, with [...]

Results of a study on ocean currents in the Gulf of Mexico's Loop Current are presented. The use of Lagranian analysis revealed characteristics not observed with the Eulerian method. The Loop Current's meander formed a new ring, and a cyclonic eddy cleaved a western anticyclonic ring.

Here we demonstrate the microfabrication of deep (>25 [[micro]meter]) polymeric microstructures created by replica-molding polydimethylsiloxane (PDMS) from microfabricated Si substrates. The use of PDMS structures in microfluidics and biological applications is discussed. We investigated the feasibility of two methods for the microfabrication of the Si molds: deep plasma etch of silicon-on-insulator (SOI) wafers and photolithographic patterning of a spin-coated photoplastic layer. Although the SOI wafers can be patterned at higher resolution, we found that the inexpensive photoplastic yields similar replication fidelity. The latter is mostly limited by the mechanical stability of the replicated PDMS structures. As an example, we demonstrate the selective delivery of different cell suspensions to specific locations of a tissue culture substrate resulting in micropatterns of attached cells.

The incorporation of monolayers of cultured hepatocytes into an extracorporeal perfusion system has become a promising approach for the development of a temporary bioartificial liver (BAL) support system. In this paper we present a numerical investigation of the oxygen tension, shear stress, and pressure drop in a bioreactor for a BAL composed of plasma-perfused chambers containing monolayers of porcine hepatocytes. The chambers consist of microfabricated parallel disks with center-to-edge radial flow. The oxygen uptake rate (OUR), measured in vitro for porcine hepatocytes, was curve-fitted using Michaelis-Menten kinetics for simulation of the oxygen concentration profile. The effect of different parameters that may influence the oxygen transport inside the chambers, such as the plasma flow rate, the chamber height, the initial oxygen tension in the perfused plasma, the OUR, and Km was investigated. We found that both the plasma flow rate and the initial oxygen tension may have an important effect upon oxygen transport. Increasing the flow rate and/or the inlet oxygen tension resulted in improved oxygen transport to cells in the radial-flow microchannels, and allowed significantly greater diameter reactor without oxygen limitation to the hepatocytes. In the range investigated in this paper (10 [[micro]meter] < H < 100 [[micro]meter]), and for a constant plasma flow rate, the chamber height, H, had a negligible effect on the oxygen transport to hepatocytes. On the contrary, it strongly affected the mechanical stress on the cells that is also crucial for the successful design of the BAL reactors. A twofold decrease in chamber height from 50 to 25 [[micro]meter] produced approximately a fivefold increase in maximal shear stress at the inlet of the reactor from 2 to 10 dyn/[cm.sup.2]. Further decrease in chamber height resulted in shear stress values that are physiologically unrealistic. Therefore, the channel height needs to be carefully chosen in a BAL design to avoid deleterious hydrodynamic effects on hepatocytes.

The objective of this investigation was to gain a deeper understanding of the intracellular events that precede photolysis of cells. A model system, consisting of malignant melanoma cells pretreated with the calcium sensitive fluorescent dye, Fluo-3, was used to examine the intracellular calcium dynamics in single-cell photolysis experiments. Exposure of the cells to 632 nm laser light in the presence of photosensitizer, tin chlorin e6, resulted in a rise in intracellular calcium. The increase in intracellular calcium was blocked using a variety of calcium channel blocking agents, including verapamil, nifedipine, and nickel. Treatment with the channel blockers was also effective in either decreasing or eliminating cell death despite the presence of lethal doses of photosensitizer and irradiation. These results show that intracellular calcium rises prior to plasma membrane lysis, and that this early rise in intracellular calcium is necessary for membrane rupture.

Ice crystallization in biological cells are detected by coupling a water transport model that defines freeze-induced cell dehydration and a diffusion-limited crystal-growth model. Cooling rate and glycerol level during intracellular growth are investigated by the model. The model is based on nucleation variables and viscosity values that are obtained from mouse oocytes.

Successful protocols for cryopreservation of living cells can be designed if the physicochemical conditions to preclude intracellular ice formation (IIF) can be defined. Unfortunately, all attempts to predict the probability of IIF have met with very limited success. In this study, an analytical model is developed to predict ice formation inside mouse oocytes subjected to a freezing stress. According to the model, IIF is catalyzed heterogeneously by the plasma membrane (i.e., surface catalyzed nucleation, SCN). A local site on the plasma membrane is assumed to become an ice nucleator in the presence of the extracellular ice via its effects on the membrane. This interaction is characterized by the contact angle between the plasma membrane and the ice cluster. In addition, IIF is assumed to be catalyzed at temperatures below -30[degrees]C by intracellular particles distributed throughout the cell volume (i.e., volume catalyzed nucleation, VCN). In the present study, these two distinctly coupled modes of IIF, especially SCN, are applied to various experimental protocols from mouse oocytes. Excellent agreement between predictions and observations suggests that the proposed model of IIF is adequate., The effect of freezing stress on the cellular characteristics of mouse oocytes was investigated using an analytical model to elucidate intracellular ice formation (IIF). The results showed that IIF is catalyzed heterogenously by the plasma membrane, and a local site on the plasma membrane becomes an ice nucleator when exposed to extracellular ice. IIF is catalyzed by intracellular particles at temperatures below 30 degrees celsius.

Objective:To evaluate the survival outcomes of patients who underwent lateral temporal bone resection as treatment for metastatic skin cancers.Methods:A single-institute, retrospective chart review was carried out on patients who underwent lateral temporal bone resection between January 2000 and December 2012. Overall survival and disease-free survival rates were calculated.Results:Forty-seven patients underwent temporal bone resection for primary (n = 21) or recurrent (n = 26) malignancies. The majority of patients (95.4 per cent) had advanced disease (stage III or IV). Average patient follow-up duration was 45 months. The 5-year and 10-year overall survival rates were 40 per cent and 23 per cent respectively. The five-year disease-free survival rate was 28 per cent.Conclusion:Aggressive initial surgical resection is warranted in the treatment of these tumours. [ABSTRACT FROM PUBLISHER]

A piezo-driven pipette that includes a small amount of mercury to enhance efficiency is widely used for mouse intracytoplasmic sperm injec-tion (ICSI). Unfortunately, the use of toxic mercury is not permitted in hospital facilities and alternatives to mercury that enhance performance of the device do not work as well in the mouse. We have eliminated mercury toxicity and obtained acceptable ICSI efficiency using a modified conventional method. With this technique, oocyte survival, fertilization (number of 2-cell) and blastocyst rates were 77/126 (61.1%), 65/77 (84.4%), and 45/65 (69.2%), respectively. Eleven live pups were born from the transfer of thirty-two 2- to 4-cell embry-os to 2 surrogate mothers. This conventional method is efficient, simple, and does not need the assistance of piezo-driven devices. [ABSTRACT FROM AUTHOR]