Effect of the shear rate and residence time on the lysis of AC16 human cardiomyocyte cells via surface acoustic waves.

The efficient breakage of one cell or a concentration of cells for releasing intracellular material such as DNA, without damaging it, is the first step for several diagnostics or treatment processes. As the cell membrane is easy to bend but resistant to stretching, the exposure of the cell to a shear rate during a short period of time can be sufficient to damage the membrane and facilitate the extraction of DNA. However, how to induce high shear stresses on cells in small microliter volumes samples has remained an elusive problem. Surface acoustic waves operating at high frequencies can induce acoustic streaming leading to shear rates sufficient to cell lysis. Lysis induced by acoustic streaming in sessile droplets has been investigated in the past from the lysis efficiency point of view. However, the effects of the velocity field and shear rate induced by acoustic streaming on the lysis process remain unexplored. Here, we study the lysis of AC16 human cardiomyocytes in microliter droplets under the effect of the shear rate induced by acoustic streaming. It is identified that for a given shear rate, the extracted DNA is also affected by the actuation period which can be attributed to a cycling process that leads to an accumulation of damage on the cell membrane.

In-droplet cell lysis of AC16 human cardiomyocyte cells via surface acoustic waves.

Although several lysis methods are available, biomedical applications are pushing the demand for miniaturised systems and thus for new ways to lyse cells in small volumes. In this work, we demonstrate in-droplet cell lysis of AC16 human cardiomyocyte cells in 20 µL droplets using high frequency surface acoustic waves. The acoustic streaming leads to high shear flow creating porous or breaking the cell membrane and releasing intracellular material. Contrary to previous work where the lysis efficiency is measured by a cell-permeant dye that can be used to determine cell viability, here we propose to quantify the DNA extracted from the cells as a measure of the lysis efficiency. This reagent-free method provides a valuable cell lysis alternative for many biological and biomedical applications, particularly for the development of point-of-care platforms.

Disseminated fusariosis in immunocompromised children: a case series and review of literature.

In the era of antifungal prophylaxis for cancer patients, Fusarium genus has become the second leading cause of invasive fungal infections and mortality in this group of patients. The intrinsic resistance to antifungal agents and the patient's risk factors are the most important variables for prognosis and survival. Currently, the use of monotherapy in comparison to combined antifungal treatment information is scarce. In this report, we present a series of three cases of children with acute lymphoblastic leukemia and disseminated fusariosis categorized according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG). Furthermore, we present a current literature review focused on treatment using monotherapy or combined antifungal treatment.

Effects of once- versus twice-a-day feeding of pasteurized milk supplemented with yeast-derived feed additives on growth and health in female dairy calves.

The objective of this study was to compare the effects of feeding preweaning dairy calves pasteurized milk once or twice a day with or without a combination of yeast-derived products. Holstein heifer calves (n = 48) from The Pennsylvania State University dairy herd were fed 3.8 L of colostrum in 1 feeding and randomly assigned to 1 of 4 treatments (once-a-day milk feeding with or without live yeast culture and mannan-rich fraction and twice-a-day milk feeding with or without live yeast culture and mannan-rich fraction). All calves were fed 6 L of milk daily. Weekly growth measurements and blood samples were taken 3 h after the morning milk feeding for all animals. Growth measurement included body weight, hip width, and withers height. Calf starter refusal was recorded weekly, and a sample was taken to determine dry matter intake. Daily health scores were recorded for each calf using a standard scoring system. Intake, growth measurements, haptoglobin, and health scores data were analyzed using repeated measures analysis with calf included as a random variable. Preweaning average daily gain was 553.4 and 512.1 g/d for calves fed milk once and twice a day, respectively, and we found no difference between treatments. Preweaning calf starter intake was 242.3 and 198.7 g/d for calves fed milk once and twice a day, respectively, and we found no treatment differences. Preweaning calf starter intake was 224.3 and 216.6 g/d for calves fed yeast and without yeast, respectively. Withers height and hip width were similar in calves fed milk either once or twice a day; however, calves fed yeast tended to have greater withers height and hip width than control calves. Haptoglobin concentration as a measure of stress had least squares means of 4.0 and 9.5 ± 3.5 µg/mL for calves fed milk once or twice a day, respectively, and we found no difference among treatments. Scours score and total daily score were similar for calves fed milk once or twice a day. These results suggest that feeding milk once a day can be successfully applied to a calf feeding system and that yeast products may improve structural growth.

Effect of different heating times of high-, medium-, and low-quality colostrum on immunoglobulin G absorption in dairy calves.

The objective of this study was to determine the effect of different durations of heat treatment on passive transfer of IgG from high-, medium- and low-quality colostrum. Colostrum was collected from The Pennsylvania State University dairy herd and divided by quality (high, medium, or low) based on colostrometer measurements. Colostrum was pooled by quality to create 3 unique batches. Each batch was further divided in thirds as follows: frozen to be fed without heat treatment, heated at 60°C for 30 min, or heated at 60°C for 60 min. Colostrum samples from each treatment were collected and analyzed for standard plate count, gram-negative noncoliforms, coliforms, and total IgG concentration. Serum samples were collected from 108 Holstein calves before feeding colostrum and 24 h after birth. Blood samples were analyzed for total protein, total IgG, and hematocrit. Colostrum quality (high, medium, or low), heat treatment (unheated, 60°C for 30 min or, 60°C for 60 min), and their interaction were analyzed as fixed effects, with calf sex included as a random block effect. Colostrum IgG was different between quality groups (92.5, 59.4, and 48.1 mg/mL of IgG). Heating colostrum reduced IgG concentration compared with the control by 9% when heated for 30 min and by 12% when heated for 60 min. Colostrum heated for 60 min had a lower standard plate count than colostrum heated for 30 min or not heated (1.8, 2.0, and 3.6 log cfu/mL, respectively). Serum IgG concentration at 24 h increased as colostrum quality increased (18.0, 22.2, and 24.8 mg/mL) and tended to increase as heat treatment time increased (19.7, 20.3, and 25.0 mg/mL of IgG). Apparent efficiency of IgG absorption was greater in calves that received medium-quality colostrum compared with calves fed high-quality colostrum (38.1 and 25.0%, respectively). These results suggest an upper limit may exist to the amount of IgG absorption in a given time period and that medium- or high-quality colostrum yields similar blood IgG concentration given the same volume of intake.

On the rational formulation of alternative fuels: melting point and net heat of combustion predictions for fuel compounds using machine learning methods.

We report the development of predictive models for two fuel specifications: melting points (T(m)) and net heat of combustion (Δ(c)H). Compounds inside the scope of these models are those likely to be found in alternative fuels, i.e. hydrocarbons, alcohols and esters. Experimental T(m) and Δ(c)H values for these types of molecules have been gathered to generate a unique database. Various quantitative structure-property relationship (QSPR) approaches have been used to build models, ranging from methods leading to multi-linear models such as genetic function approximation (GFA), or partial least squares (PLS) to those leading to non-linear models such as feed-forward artificial neural networks (FFANN), general regression neural networks (GRNN), support vector machines (SVM), or graph machines. Except for the case of the graph machines method for which the only inputs are SMILES formulae, previously listed approaches working on molecular descriptors and functional group count descriptors were used to develop specific models for T(m) and Δ(c)H. For each property, the predictive models return slightly different responses for each molecular structure. Therefore, models labelled as 'consensus models' were built by averaging values computed with selected individual models. Predicted results were then compared with experimental data and with predictions of models in the literature.

Platelet aggregation in different antithrombotic regimens. Possible proaggregant effect of low level oral anticoagulation.

UNLABELLED: Few trials have studied platelet activity during oral anticoagulation and all show a tendency for platelet aggregation to increase. This adverse effect has also been shown in some patients treated with unfractionated heparin, the so-called white clot syndrome. We studied platelet aggregation in patients with atrial fibrillation enrolled in the NASPEAF study and receiving antiaggregant, anticoagulant and both treatments. METHODS: 15 healthy control subjects (group C) and 99 patients were enrolled, the latter receiving 4 different antithrombotic regimens for platelet aggregation: group 1, 600 mg of the antiplatelet drug triflusal; group 2, anticoagulation for an INR of 2-3; and both treatments with 2 different levels of anticoagulation, mean INR of 1.85 (group 3) and of 2.15 (group 4). The same amounts of the agonists ADP, arachidonic acid and collagen were used in all tests. For statistical analysis we used the interval in min, from the addition of the agonist to the beginning of aggregation and the % of aggregation at 5 and 8 min. RESULTS: After arachidonic acid was given, the interval to the beginning of aggregation was shorter in group 2 than in group C: 0.6 +/- 0.21 and 1.1 +/- 1.2, and in both was significantly shorter than in the other three receiving antiplatelet drugs alone: group 1 = 1.58 +/- 1.4 or combined with anticoagulants: group 3 = 1.7 +/- 1.7 and group 4 = 2.4 +/- 2.1. The % of aggregation at 5 min, in groups C, 2, 1, 3 and 4 was respectively 48 +/- 24, 43.2 +/- 19, 29.6 +/- 17, 34.8 +/- 22 and 23.2 +/- 22.5. The data showed significantly increased platelet activity in groups C and 2 compared to groups 1, 3 and 4. Group 3 with a low anticoagulation level (mean INR = 1.85) showed a tendency to greater platelet activity than group 1 and 4 with p value = 0.08. CONCLUSIONS: The antiplatelet drug triflusal alone or combined with a therapeutic level of anticoagulation effectively reduces platelet aggregation and is not influenced by anticoagulant treatment. A low level of anticoagulation (INR < 2) shows a tendency to increase platelet activity.

Ethnicity and negative symptoms in patients with schizophrenia.

The purpose of this study was to assess ethnic differences in the negative symptom profile of 25 Anglo American and 26 Mexican American subjects with schizophrenia. Subjects were rated at the end of a 1-2-week medication washout period (time 1) and at discharge (time 2) with the Negative Symptoms Assessment (NSA), Brief Psychiatric Research Scale, (BPRS), the [Diagnostic and Statistical Manual of Mental Disorders (4th edition)] DSM-IV negative factor score and LAECA acculturation scale. Total NSA scores were significantly higher among Mexican Americans both at time 1 and time 2. Among the five subscales of the NSA, ethnic differences were significant only for the Cognition subscale at time 1. Results indicate no ethnic differences in core negative symptoms (alogia, avolition, flat affect), but do suggest that a cognition-related factor differs between Mexican American and Anglo American schizophrenic patients.

[Spinal cord compression secondary to epidural extramedullary hematopoiesis in thalassemia: a clinical case and review of literature]. / Compresión medular secundaria a hematopoyesis extramedular epidural en talasemia: caso clínico y revisión de la literatura.

INTRODUCTION: Extramedullary hematopoiesis generally occurs in a variety of hematological disorders where the normal functioning of the blood forming organs is disturbed. It is a common manifestation in thalassemia where it occurs as a compensatory phenomenon in order to combat long standing anemia. Spinal cord compression as a consequence of extramedullary hematopoiesis in the intraspinal epidural space is an extremely rare complication, though this complication has been reported more commonly in thalassemia. CLINICAL CASE: A case of spinal cord compression due to extramedullary hematopoiesis in a patient with thalassemia is reported. The patient was successfully treated with radiation therapy and blood transfusions and he made a complete clinical recovery. Development. The literature is reviewed and the efficacy of several treatments such as surgery, radiotherapy and blood transfusion therapy is discussed. Until recently surgical decompression followed by radiation therapy remained the recommended treatment. Hematopoietic tissue is particularly sensitive to the ionizing radiation and low-dose radiotherapy is enough to relieve the spinal cord compression. Blood transfusion therapy may be diagnostically and therapeutically useful in the management of this entity. CONCLUSIONS: A prompt recognition of the syndrome and early treatment with radiotherapy and blood transfusion therapy is recommended to prevent irreversible damage to the spinal cord. Surgery may be only considered in the event of progressive neurological deficit despite of radiotherapy or blood transfusion therapy.

[The treatment of tracheobronchial ruptures: a review of 6 cases]. / Tratamiento de las roturas traqueobronquiales: revisión de 6 casos.

Tracheobronchial ruptures represent a serious pathology difficult to diagnose at the first examination. The authors review 6 cases: four as acute types with pneumomediastinum, pneumothorax and subcutaneous emphysema with a delay in diagnosis of 3.25 days, meanwhile 2 cases were chronic forms with a delay in diagnosis of 124.5 days. Diagnosis should be performed as soon as possible based in the presence of uni or bilateral pneumothorax with pneumomediastinum being confirmed by fiber bronchoscopy. The treatment is based in the resection of the fractured fragments, followed by bronchoplasty always with reabsorbable sutures the most frequent surgical technique, meanwhile in the atelectatic forms it is not possible to perform sometimes and we must practise lung resections.

Schizophrenia among Hispanics: epidemiology, phenomenology, course, and outcome.

A number of studies point to the influence of culture and ethnicity on the presentation and course of schizophrenia. In general, a relatively powerful influence of environmental factors is identified. This article reviews the literature on schizophrenia among Hispanics in the United States and uses the results of this review as a basis for identifying directions for future study. Research is divided into three major areas: epidemiology, phenomenology, and illness course and outcome. Ethnic comparisons suggest similar prevalence rates of schizophrenia. However, differences in illness phenomenology between certain subgroups of Hispanics are also observed. Moreover, culture can affect various aspects of the illness process, including illness definition, help- seeking behavior, response to treatment, and post-treatment adjustment. Proposed guidelines to direct future research ventures include (1) better delineation of the sociocultural attributes of the group under study, (2) validation of assessment instruments across ethnic groups, (3) use of innovative approaches to assess incidence and prevalence, (4) incorporation of qualitative methodology, (5) use of illness behavior models to provide a conceptual framework to guide investigations, and (6) integration of cross-cultural and biological studies.

Bronchovascular mucormycosis: an urgent surgical problem.

The case of a 70-year-old male with lymphoblastic leukemia is reviewed, who presented the rare and almost always fatal complication of pulmonary mucormycosis, but who was treated satisfactorily with amphotericin B and surgery. The risk of massive hemoptysis in the course of mucormycosis that invades the lung vessels, makes us believe that surgery is an essential part of the management of this disease. It is suggested that the patient be operated as soon as the diagnosis is obtained, as we did in our case, to avoid other risks in combined management with amphotericin B.