Bipedicled fronto-occipital flap for reconstruction of postoncologic defects of the lateral scalp

Presented here are two clinical cases of extensive defects of the scalp secondary to surgical resection of invasive basal cell carcinoma on the parietal region, successfully treated by means of very large, bipedicled fronto-occipital flaps, based anteriorly on the supratrochlear-supraorbital vessels and posteriorly on the occipital and posterior auricular vessels. Considering both the location and the large size of the scalp defects, different surgical techniques are discussed and the potential use of bipedicled scalp flaps is considered, designed either sagittally or coronally as fronto-occipital or temporo-temporal flaps. The bipedicled fronto-occipital scalp flap is believed to represent a simple, secure, and useful reconstructive procedure for cutaneous coverage of extensive defects located on the lateral scalp.     

Differences in secondary structure of HAV-synthetic peptides induced by the sequential order of T- and B-cell epitopes

The present study was undertaken to examine the structural features of two peptide constructs designed on the basis of linear combination of B and T-cell epitopes in different orientations (BT and TB) that may be important to explain the differences in the elicited antihepatitis A virus immune response and in the interaction with biological model membranes. A CD study was carried out and the corresponding quantitative analysis of the experimental data was done using deconvolution computer programs. Moreover, fluorescence experiments were performed to analyze differences in the fluorescence emission spectra of both molecules. The main conformational difference by CD studies was obtained working in aqueous medium. Although the TB sequence adopted a preferably random coil structure, the BT peptide was best fitted with beta-type structures. These results are further supported by fluorescence studies. These findings have relevance for the design of synthetic immunopeptides.     

Validation of data collection for an American trypanosomiasis epidemiologic study in the State of Morelos, México]

The purpose of this paper is to show up the importance of the standardization concepts in American Trypanosomiasis epidemiological studies. The consistence in the measurement of some dwelling characteristics was evaluated. A validation of the Queretaro antigen for indirect hemagglutination reaction as a diagnostic test and the interobserver concordance for the serologic readings were also made. The observers were instructed in some sessions. The pretests were made in the laboratory with positive and negative sera, with sera from the studied population. Results show that the interobserver concordance after the instruction, for the dwelling variables ranged from 70% to 100%. Sensitivity of the Queretaro antigen was 100%, specificity 55%, the predictive value of a positive test 55%, and the predictive value of a negative test 93%. The interobserver concordance was 47%. The pretest and the pilot study are very important in getting the objectives of the principal study.     

Smaug/SAMD4A Restores Translational Activity of CUGBP1 and Suppresses CUG-Induced Myopathy

We report the identification and characterization of a previously unknown suppressor of myopathy caused by expansion of CUG repeats, the mutation that triggers Myotonic Dystrophy Type 1 (DM1). We screened a collection of genes encoding RNA–binding proteins as candidates to modify DM1 pathogenesis using a well established Drosophila model of the disease. The screen revealed smaug as a powerful modulator of CUG-induced toxicity. Increasing smaug levels prevents muscle wasting and restores muscle function, while reducing its function exacerbates CUG-induced phenotypes. Using human myoblasts, we show physical interactions between human Smaug (SMAUG1/SMAD4A) and CUGBP1. Increased levels of SMAUG1 correct the abnormally high nuclear accumulation of CUGBP1 in myoblasts from DM1 patients. In addition, augmenting SMAUG1 levels leads to a reduction of inactive CUGBP1-eIF2α translational complexes and to a correction of translation of MRG15, a downstream target of CUGBP1. Therefore, Smaug suppresses CUG-mediated muscle wasting at least in part via restoration of translational activity of CUGBP1.     

A comprehensive computational model of animal biosonar signal processing

Computational models of animal biosonar seek to identify critical aspects of echo processing responsible for the superior, real-time performance of echolocating bats and dolphins in target tracking and clutter rejection. The Spectrogram Correlation and Transformation (SCAT) model replicates aspects of biosonar imaging in both species by processing wideband biosonar sounds and echoes with auditory mechanisms identified from experiments with bats. The model acquires broadband biosonar broadcasts and echoes, represents them as time-frequency spectrograms using parallel bandpass filters, translates the filtered signals into ten parallel amplitude threshold levels, and then operates on the resulting time-of-occurrence values at each frequency to estimate overall echo range delay. It uses the structure of the echo spectrum by depicting it as a series of local frequency nulls arranged regularly along the frequency axis of the spectrograms after dechirping them relative to the broadcast. Computations take place entirely on the timing of threshold-crossing events for each echo relative to threshold-events for the broadcast. Threshold-crossing times take into account amplitude-latency trading, a physiological feature absent from conventional digital signal processing. Amplitude-latency trading transposes the profile of amplitudes across frequencies into a profile of time-registrations across frequencies. Target shape is extracted from the spacing of the object’s individual acoustic reflecting points, or glints, using the mutual interference pattern of peaks and nulls in the echo spectrum. These are merged with the overall range-delay estimate to produce a delay-based reconstruction of the object’s distance as well as its glints. Clutter echoes indiscriminately activate multiple parts in the null-detecting system, which then produces the equivalent glint-delay spacings in images, thus blurring the overall echo-delay estimates by adding spurious glint delays to the image. Blurring acts as an anticorrelation process that rejects clutter intrusion into perceptions.     

Coagulation activation in an experimental pneumonia model in malnourished mice

Malnutrition induces a decrease in immunity that affects the ability of the organism to deal with an infectious challenge. The clotting system is considered a branch of immunity and its activation is important in the pathogenesis of an infectious disease. This work was conducted to determine coagulation modifications in malnourished hosts before and during infection. Weaned mice were malnourished via a protein-free diet. Well-nourished control mice (WNC) consumed a balanced conventional diet. Malnourished mice (MN) and WNC were challenged intranasally with Streptococcus pneumoniae. Blood, bronchoalveolar lavages (BAL), and lung samples were taken at different times post infection. The results were that MN showed altered hemostatic tests and fibrin(ogen) deposits in the lung. Thus, an increase in thrombin-antithrombin complexes (TATc) in plasma and BAL was observed. In the MN group, infection induced a rise in TATc in plasma and BAL and increased plasma fibrinogen and fibrin(ogen) deposits in the lung. A decrease in activated protein C and antithrombin in BAL and an early decrease followed by an increase in plasma Factor VIII were also observed. Thus, malnourishment induced a procoagulant state increased by infection. This is the first work that presents results of an exhaustive study of coagulation in malnourished hosts before and during an infection.