Phenytoin penetration into brain after administration of phenytoin or fosphenytoin

Paraneoplastic pemphigus (PNP) is an autoimmune blistering disease that occurs in association with underlying neoplasms. PNP patients develop characteristic autoantibodies directed against multiple antigens, mostly identified as members of the plakin family of cytoplasmic proteins (desmoplakin I and II, bullous pemphigoid antigen I, envoplakin, and periplakin). HD1/plectin, another member of the plakin family, has not previously been detected in the characteristic PNP antigen complex, which may relate to practical difficulties associated with its large size (molecular weight approximately 500 kDa). In this study, a combination of immunoprecipitation and immunoblot is used to demonstrate that HD1/plectin is also recognized by sera from PNP patients. Thirteen of 16 PNP sera tested were positive for HD1/plectin compared with none of 43 control sera (11 pemphigus vulgaris, 11 pemphigus foliaceus, 11 bullous pemphigoid, and 10 normal individuals). Combined with our recent finding that desmoglein 3 and desmoglein 1 are cell surface target antigens in PNP, this demonstration of plectin/HD1 as another component of the antigen complex in PNP confirms that PNP is an autoimmune disease against desmoglein and plakin family molecules.     

South-east asian ovalocytic (SAO) erythrocytes have a cold sensitive cation leak: implications for in vitro studies on stored SAO red cells

South-east Asian ovalocytosis (SAO) results from the heterozygous presence of an abnormal band 3, which causes several alterations in the properties of the erythrocytes. Although earlier studies suggested that SAO erythrocytes are refractory to invasion in vitro by the malarial parasite Plasmodium falciparum, a more recent study showed that fresh SAO cells were invaded by the parasites, but became resistant to invasion on storage because intracellular ATP was depleted more rapidly than normal. Here we show that SAO red cells are much more leaky to sodium and potassium than normal red cells when stored in the cold. This leak was much less marked when the cells were stored at 25 or 37 degreesC. Incubation for 3.5 h at 37 degreesC of cold-stored SAO red cells did not restore sodium and potassium to normal levels, probably because the depleted ATP level in cold-stored SAO red cells is further reduced with incubation at 37 degreesC. The increased leakiness of SAO red cells is non-specific and extends to calcium ions, taurine, mannitol and sucrose. These results suggest that SAO red cells undergo a structural change on cooling. Since many of the reports describing altered properties of SAO red cells have used cells which have been stored in the cold, these results need re-evaluation using never-chilled SAO red cells to assess whether the cells have the same abnormal properties under in vivo conditions.     

Constant-frequency sliding-mode and PI linear controllers for powerrectifiers: a comparison

Constant-frequency sliding-mode and linear proportional integral (PI) cascaded controllers (internal current loop and external output voltage control loop) for 12-pulse thyristor rectifiers are designed, using new models and convenient assumptions, and their performances compared. The use of sliding-mode control on line-commutated power converters implies the use of fixed-frequency sliding-mode design, originating steady-state errors. These are eliminated using a higher order switching function, with fourth-order Bessel polynomial coefficients, to minimize the response time and to eliminate the overshoot in the reaching mode. Comparisons are made using simulations (MATLAB/SIMULINK blocks) and experimental results. The sliding-mode controllers, as well as the PI controllers, need almost the same hardware and present no steady-state errors and no output voltage overshoots. Besides allowing a faster dynamics than the PI controllers, the proposed sliding-mode approach provides a new, nonlinear theoretical frame for solving the control problem of power rectifiers with output filters     

High-pressure destruction kinetics of Listeria monocytogenes on pork

OBJECTIVE: To define the incidence of complications of endotracheal intubation and the factors associated with these complications. STUDY DESIGN: During a 22-month period, 227 intubated infants weighing <1,501 g were followed prospectively in a neonatal intensive care unit. Detailed records of events associated with airway management were kept after every intubation, in addition to clinical data. RESULTS: Eleven infants (4.8%) developed respiratory stridor after extubation which was treated with either systemic corticosteroids, racemic epinephrine and/or reintubation for respiratory failure. Four infants were submitted for bronchoscopy, mild subglottic stenosis with tracheal edema was found in 1 patient, granulation tissue and airway edema were noted in 3 infants. Traumatic intubation, prolonged ventilation, multiple intubations and bacterial colonization of the endotracheal tube were the factors associated with postextubation stridor. CONCLUSIONS: Subglottic stenosis is an infrequent complication of endotracheal intubation with current airway management of very-low-birth-weight infants. Less severe complications are still common, but they are usually amenable to clinical treatment. Bronchoscopy should be performed selectively only in infants with clinical evidence of airway obstruction after extubation.     

Evaluation of enzyme-linked immunosorbent assay for the diagnosis of Helicobacter pylori infection in children from different age groups with and without duodenal ulcer

BACKGROUND: Myocardial ischemia induced by 5-fluorouracil (5-FU) is a relatively rare, but potentially serious, occurrence. Some case reports have indicated that recurrent ischemia may be prevented if 5-FU is resumed after pretreatment with antianginal therapy. METHODS: A 54-year old woman was diagnosed with stage IIA squamous cell carcinoma of the anus. Treatment with concurrent radiation and chemotherapy (mitomycin-C and 5-FU) was initiated with curative intent. RESULTS: The patient had no evidence of underlying coronary artery disease based on history, physical examination or ECG. Approximately 48 h after initiation of 5-FU infusion the patient developed anginal pain associated with ECG changes compatible with ischemia. After resolution of ischemia and ruling out of myocardial infarction, coronary arteriography demonstrated normal coronary arteries. In an attempt to prevent myocardial ischemia, calcium channel blocker and nitrate therapy was started, but anginal pain with ECG change recurred when 5-FU was resumed. This necessitated selection of an alternative chemotherapy regimen. CONCLUSIONS: Even in the presence of normal coronary arteries, antianginal therapy may not preclude the occurrence of potentially serious 5-FU induced myocardial ischemia. For patients who experience 5-FU-induced myocardial ischemia, development of alternative chemotherapy regimens should be considered.     

Retrofitting of industrial olefin polymerization plants: producing broad MWDs through multiobjective periodic operation

The drop‐in of metallocene catalysts (MCs) in existing industrial polymerization plants is the current goal of most polymer producers. However, the narrow molecular weight distribution (MWD) of the polymers produced by MCs prevent them of moving into commodities market dominated by conventional Ziegler–Natta catalysts, where ease of processing is an essential property. Broader MWDs may be obtained through mixing of different MCs or blending of different resins, but resin‐compatibility problems and complex undesirable catalyst interactions pose technological problems that have yet to be solved. For these reasons, modern olefin polymerization plants have to work with both catalysts to respond to market demands, resulting in costly operations of grade/catalyst change. In this article, we describe how periodic control of short residence‐time reactors operating with an MC (Me₂Si(2‐Me‐Benz[e]Ind)₂ZrCl₂/MAO) can lead to polymers with broad MWD and, consequently, to high processability. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 437–452, 2000     

Aflatoxin production in three selected samples of triticale,wheat and rye grown in Argentina

Little is known about mycotoxin contamination of triticale, a hybrid resulting from crossing wheat and rye. The purpose of the present work was to evaluate triticale as a substrate for aflatoxin accumulation in comparison with its parents. Aflatoxin (B₁, B₂, G₁ and G₂) accumulation curves were obtained for the three substrates inoculated with Aspergillus parasiticus NRRL 2999 and incubated at 25 °C and water activity 0.925 for 10 weeks. Wheat and triticale were poor substrates for aflatoxin production. Rye was more prone than the other substrates to fast colonisation by A parasiticus and accumulated larger aflatoxin quantities over the whole incubation period. The maximum aflatoxin concentration in rye (11 840 µg kg⁻¹) was significantly larger (p < 0.05) than those obtained in wheat (2150 µg kg⁻¹) and triticale (2850 µg kg⁻¹). © 2000 Society of Chemical Industry     

Heat–Moisture Treatment on Pinhão Starch Impacts the Properties of the Biodegradable Films

Using non-conventional starch can benefit the industry since it can present different properties. It also can lead to new properties upon physical modification, which improves its derivate film properties. Therefore, the aim of this work is to evaluate the heat–moisture treatment (HMT) on pinhão starch and its effectiveness in film properties. After isolation using water as a solvent, the pinhão starch is treated by HMT for 16 h at 110 °C. Native and HMTed starches are used to produce biodegradable films. Pinhão starch and starch films chemical and physical properties are properly characterized. The HMT causes some changes in short-range ordered structures, reduces the relative crystallinity, and shifts the pinhão starch from C-type to A-type. Also, HMT decreases the peak viscosity and the breakdown, and improves thermal stability. These starch changes upon HMT reduces water vapor permeability, increases tensile strength, and elongation at the break of pinhão starch films. Desirable changes in starch and film properties are achieved by physically modifying pinhão starch using HMT, which is a promising alternative to chemical modifications.     

Synergy in Cystic Fibrosis Therapies: Targeting SLC26A9

SLC26A9, a constitutively active Cl⁻ transporter, has gained interest over the past years as a relevant disease modifier in several respiratory disorders including Cystic Fibrosis (CF), asthma, and non-CF bronchiectasis. SLC26A9 contributes to epithelial Cl⁻ secretion, thus preventing mucus obstruction under inflammatory conditions. Additionally, SLC26A9 was identified as a CF gene modifier, and its polymorphisms were shown to correlate with the response to drugs modulating CFTR, the defective protein in CF. Here, we aimed to investigate the relationship between SLC26A9 and CFTR, and its role in CF pathogenesis. Our data show that SLC26A9 expression contributes to enhanced CFTR expression and function. While knocking-down SLC26A9 in human bronchial cells leads to lower wt- and F508del-CFTR expression, function, and response to CFTR correctors, the opposite occurs upon its overexpression, highlighting SLC26A9 relevance for CF. Accordingly, F508del-CFTR rescue by the most efficient correctors available is further enhanced by increasing SLC26A9 expression. Interestingly, SLC26A9 overexpression does not increase the PM expression of non-F508del CFTR traffic mutants, namely those unresponsive to corrector drugs. Altogether, our data indicate that SLC26A9 stabilizes CFTR at the ER level and that the efficacy of CFTR modulator drugs may be further enhanced by increasing its expression.