Early use of non invasive ventilation in patients with amyotrophic lateral sclerosis: what benefits?

OBJECTIVE

The aim of this study was to analyze the efficacy of an early start of NIV in ALS patients, evaluating respiratory and ventilatory parameters.

PATIENTS AND METHODS

Functional respiratory parameters and arterial blood gas analysis were evaluated in forty-six patients. All patients were informed about the benefits and possible adverse effects of therapeutic support with NIV and divided in two groups based on the compliance to early start therapy with NIV (Group A) or not (Group B).

RESULTS

Among 46 ALS patients consecutively visited in our Unit, we included 20 patients in the Group A and 16 in the Group B. We have emphasized the importance of the early use of NIV stressing the difference between two groups analyzed, particularly in terms of pulmonary function tests and arterial blood gas analysis. Significant correlation was observed between Vital Capacity (VC), Forced Expiratory volume in one second (FEV1), and maximal inspiratory pressures (PImax).

CONCLUSIONS

Our study highlights the importance of noninvasive mechanical ventilation as a treatment for ALS patients and also shows the early start of NIV as an important approach in order to postpone the functional decline and the decrease of respiratory muscle strength.

Atrial fibrillation in the acute, hypercapnic exacerbations of COPD

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) has been associated with a high frequency of arrhythmias. Atrial fibrillation (AF) is one of the most common arrhythmias and causes substantial morbidity and mortality. Emerging risk factors for the development of AF include a variety of breathing disorders like COPD. Few studies have analyzed the role of reduced lung function and respiratory acidosis in predicting AF. Aim of the current study was to investigate the role of hypercapnia, pulmonary systolic hypertension and lung function impairment in COPD patients, as risk factors for atrial fibrillation development.

PATIENTS ANDV METHODS

We evaluated a population of individuals consecutively hospitalized for COPD exacerbation and hypercapnic respiratory failure between January 2012 and January 2013; among them we selected a subgroup of patients presenting a paroxysmal episode of atrial fibrillation. All patients underwent pulmonary function tests, haemogasanalysis, electrocardiogram and transthoracic echocardiography.

RESULTS

Among the 193 subjects evaluated, 35 individuals with AF and COPD were enrolled in the study. Risk of new AF was higher in those subjects with lower FEV1 and higher PaCO2 values, also there was a significantly increased prevalence of AF in patients with higher value of Pulmonary Artery Systolic Pressure (PASP), obtained by transthoracic echocardiography. Linear correlation between variables revealed a direct relationships between hypercapnia and PASP and left and right atrial areas.

CONCLUSIONS

Impaired pulmonary function, hypercapnia and high values of PASP are independent predictors of incident AF.

Covert brand recognition engages emotion-specific brain networks

Consumer goods' brands have become a major driver of consumers' choice: they have got symbolic, relational and even social properties that add substantial cultural and affective value to goods and services. Therefore, measuring the role of brands in consumers' cognitive and affective processes would be very helpful to better understand economic decision making. This work aimed at finding the neural correlates of automatic, spontaneous emotional response to brands, showing how deeply integrated are consumption symbols within the cognitive and affective processes of individuals. Functional magnetic resonance imaging (fMRI) was measured during a visual oddball paradigm consisting in the presentation of scrambled pictures as frequent stimuli, colored squares as targets, and brands and emotional pictures (selected from the International Affective Picture System [IAPS]) as emotionally-salient distractors. Affective rating of brands was assessed individually after scanning by a validated questionnaire. Results showed that, similarly to IAPS pictures, brands activated a well-defined emotional network, including amygdala and dorsolateral prefrontal cortex, highly specific of affective valence. In conclusion, this work identified the neural correlates of brands within cognitive and affective processes of consumers.

Cross-sectional imaging of individual layers and buried interfaces of graphene-based heterostructures and superlattices

By stacking various two-dimensional (2D) atomic crystals on top of each other, it is possible to create multilayer heterostructures and devices with designed electronic properties. However, various adsorbates become trapped between layers during their assembly, and this not only affects the resulting quality but also prevents the formation of a true artificial layered crystal upheld by van der Waals interaction, creating instead a laminate glued together by contamination. Transmission electron microscopy (TEM) has shown that graphene and boron nitride monolayers, the two best characterized 2D crystals, are densely covered with hydrocarbons (even after thermal annealing in high vacuum) and exhibit only small clean patches suitable for atomic resolution imaging. This observation seems detrimental for any realistic prospect of creating van der Waals materials and heterostructures with atomically sharp interfaces. Here we employ cross sectional TEM to take a side view of several graphene-boron nitride heterostructures. We find that the trapped hydrocarbons segregate into isolated pockets, leaving the interfaces atomically clean. Moreover, we observe a clear correlation between interface roughness and the electronic quality of encapsulated graphene. This work proves the concept of heterostructures assembled with atomic layer precision and provides their first TEM images.

Treatment of acute exacerbations with non-invasive ventilation in chronic hypercapnic COPD patients with pulmonary hypertension

BACKGROUND AND OBJECTIVES

Chronic Obstructive Pulmonary Disease (COPD) is a slowly progressive airways disorder characterized by not fully reversible airflow obstruction, often presenting exacerbations of respiratory symptoms requiring hospitalization. Non-Invasive Ventilation (NIV) has been shown to be an effective adjunct to standard medical therapy in the treatment of acute respiratory failure. Secondary pulmonary hypertension leads to a rapid progression of the disease.

AIM

To evaluate the effect of NIV treatment in patients with acute exacerbation of COPD, with or without respiratory acidosis, and its effect in patients with pulmonary hypertension.

PATIENTS AND METHODS

We enrolled 61 consecutive subjects (M 41; F 20) with COPD admitted to our respiratory ward for acute respiratory exacerbation. Patients were divided into two groups on the basis of arterial pH (group A: 26 individuals with pH <7.35; group B: 35 with pH > or =7.35) and treated with optimal medical therapy (oxygen-therapy, systemic corticosteroids, bronchodilators, antibiotics) and NIV. Moreover, we evaluated functional autonomy thought Six Minute Walking Test (6 mWT), and pulmonary arterial pressure (by transthoracic echocardiography).

RESULTS

In group A NIV treatment was associated to a total regression of uncompensated respiratory acidosis (pH 7.36 vs. 7.29). In both groups we observed a significant reduction of PaCO2 (group A: 77.14 +/- 10.4 vs. 45.1 +/- 2.8 mmHg; group B: 70.1 vs. 44 +/- 3.9 mmHg) and an improvement in PaO2 (group A: 51.2 +/- 10.3 vs 84.2 mmHg; group B: 59 +/- vs. 87 +/- 3.3 mmHg). Total average duration of NIV administration was longer in Group A than in Group B (81.14 hours vs 55.83 hours). At the end of NIV treatment, we observed improvement in the autonomy of walking (175.1 meters vs 118.4 meters) in both groups. Patients with severe pulmonary hypertension (PASP > or =55 mmHg) showed a lower reduction of PaCO2 (47.8 vs. 43.7 mmHg) and a minor improvement of arterial pH (7.37 vs. 7.41) compared to patients with a lower value of pulmonary hypertension.

CONCLUSIONS

In this study we showed that NIV is useful in patients with or without uncompensated respiratory acidosis, through the improvement of symptoms, blood gases parameters, and walking autonomy. Patients with severe pulmonary hypertension are associated with poorer response to NIV treatment.

Sequence Diversity in tRNA Gene Locus A-L among Iranian Isolates of Entamoeba dispar

BACKGROUND

A number of methods for detecting diversity in Entamoeba have been described over the years. In the present study the genetic polymorphism of noncoding locus A-L was analyzed using PCR and sequencing in order to clarify the genotypic differences among E. dispar isolates.

METHODS

A total of 28 E. dispar from patients with gastrointestinal symptoms were determined and the genomic DNA was extracted directly from stool. For genotype analysis; Locus A-L was amplified by PCR and PCR products were sequenced. The sequences obtained were edited manually and aligned using Gene Runner software.

RESULTS

With sequencing of PCR products a reliable genetic diversity in size, number and position of the repeat units were observed among the Iranian E. dispar isolates in locus A-L gene. Sequences showed variation in length from 448bp to 507bp and seven distinct types were identified.

CONCLUSION

The genetic diversity of loci like A-L shows them to be suitable for epidemiological studies such as the characterization of the routes of transmission of these parasites in Iran.

Molecular epidemiology of cryptosporidiosis in Iranian children, tehran, iran

BACKGROUND

Cryptosporidium is a worldwide protozoan parasite and one of the most common causes of infection and diarrhea in humans and cattle. The aim of the present study was determination of subtypes of Cryptosporidium among children with diarrhea in Tehran by sequence analysis of the highly polymorphic 60-kDa glycoprotein (GP60) gene.

METHODS

Fecal samples were collected from 794 diarrheic children. Initial identification of Cryptosporidium was carried out on stool samples by Ziehl-Neelsen acid-fast staining method. DNA was extracted from positive microscopically samples and Cryptosporidium genotypes and subtypes were determined, accordingly.

RESULTS

Out of 794 collected samples, 19 (2.40%) were positive for Cryptosporidium oocysts. Sequences analysis of GP60 gene showed that 17 (89.47%) of the positive isolates were Cryptosporidium parvum and 2 (10.52%) were C. hominis. All subtypes of C. parvum isolates belonged to allele families IIa (6/17) and IId (11/17). The most common allele in all 17 isolates belonged to IId A20G1a (41.18%). A22G1 (IF) subtype was detected in two C. hominis isolates of the children.

CONCLUSION

The predominancy of C. parvum species (specially, IId A20G1a subtype) in current study underlines the importance of zoonotic Cryptosporidium transmission in Iran.

A comparative study of the responses of lithium borate and calcium sulphate phosphors in a TL personal dosemeter

This work summarises the results of a series of experiences made on Panasonic UD-802AS, a multi-element dosemeter that is currently used in Caorso Nuclear Power Plant for personnel external monitoring. Two main topics have been considered: energy response and the influence of working place dose rate on relative readings of the elements at the end of the monitoring period. The presence of four elements of different materials and filtrations gives the possibility of evaluating radiation energy by a simple algorithm, so that an accurate estimate of the personal dose equivalent can be provided; the good results of the participation of Caorso Individual Monitoring Service (IMS) to 'EURADOS 2008 intercomparison on whole-body dosemeters' account for the reliability of the method. A study on the response in low-dose rate fields is also reported, giving in practice interesting information about operational conditions.

Liquid injection atomic layer deposition of silver nanoparticles

Silver nanoparticles are being developed for applications in plasmonics, catalysts and analytical methods, amongst others. Herein, we demonstrate the growth of silver nanoparticles using an atomic layer deposition (ALD) process for the first time. The silver was deposited from pulses of the organometallic precursor (hfac)Ag(1,5-COD) ((hexafluoroacetylacetonato)silver(I)(1,5-cyclooctadiene)) dissolved in a 0.1 M toluene solution. Catalytic oxidative dehydrogenation of the silver was achieved using intermittent pulses of propanol. The effect of substrate temperature on the size and distribution of nanoparticles has been investigated over the temperature range 110-150 degrees C. Transmission electron microscopy reveals that the nanoparticles consist of face centred cubic, facetted silver crystallites. The localized surface plasmon modes of the nanoparticles have been investigated using electron energy loss spectroscopy mapping. The distributions of plasmons within the ALD nanoparticles are comparable to those grown by solution methods. Both dipolar and quadrupolar resonant modes are observed, which is consistent with previous discrete dipole approximation models. Energy loss mapping of a loss feature at 8.1 eV reveals that it correlates with the bulk or volume region of the silver nanoparticles investigated here.

Déficit homozygote en antithrombine de type HBS; à propos d'une famille

Congenital antithrombin (AT) deficiency is the most thrombotic genetic abnormality of haemostasis. Total quantitative deficits are lethal as early as life intra-uterine. Only homozygous mutations concerning the heparin-binding site are compatible with life. We report here the case of an 18 years old patient with recurrent deep venous thrombosis of the inferior members. Haemostasis exploration shows a decreased AT activity (11%) in the presence of heparin while AT progressive activity and AT antigen are normal. Two other homozygous sisters are identified in this family study. Molecular study of AT gene show Arg47-Cys substitution, already reported in the literature with patients of different geographic origins. Treatment of patients with homozygous AT type HBS deficiency is similar that for patients with heterozygous AT deficiency; a continuous prophylactic anticoagulant treatment is always necessary and AT concentrates infusions are required in all situations needing curative heparin treatment.

Analysis of urinary N-acetyl-S-(N-methylcarbamoyl)cysteine, the mercapturic acid derived from N,N-dimethylformamide

Human biotransformation of the industrial solvent N,N-dimethylformamide gives raise to N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) which has the longest half-life (about 23 h) among urinary metabolites of N,N-dimethylformamide. It could be used for monitoring industrial exposure over several workdays, by measuring it in urine samples collected at the end of the working week. This is consistent with the suggestions of the American Conference of Governmental Industrial Hygienists, which established a limit of 40 mg/l for the year 2000. An easy, cheap and user-friendly method has been developed for determination of urinary AMCC. Unlike currently available methods, it requires neither a time-consuming preparation phase nor gas chromatographic analysis with a nitrogen-phosphorus or mass detector. The method uses high-performance liquid chromatography (HPLC), with an UV detector at 436 nm. A 10-microl volume of urine is added to a carbonate-hydrogen carbonate buffer and mixed with a dabsyl chloride solution in acetonitrile. The reaction between AMCC and the reagent is performed at 70 degrees C for 10 min. The 'dabsylated' product is stable for at least 12 h. After brief centrifugation, the solution is ready for HPLC analysis using a C18 column (250 x 4.6 mm, 5 microm). The method is sensitive (detection limit 1.8 mg/l) and specific. It identified urinary AMCC in urine of 40 subjects not exposed to N,N-dimethylformamide with a median concentration of 3.9 mg/l. In urine samples from 20 workers exposed to N,N-dimethylformamide (5-40.8 mg/m3), AMCC concentrations ranged from 16 to 170 mg/l. Industrial toxicology laboratories with limited instrumentation will be able to use it in the biological monitoring of workers exposed to N,N-dimethylformamide.

The EGF and FGF receptors mediate neuroglian function to control growth cone decisions during sensory axon guidance in Drosophila

Cell adhesion molecules (CAMs) implement the process of axon guidance by promoting specific selection and attachment to substrates. We show that, in Drosophila, loss-of-function conditions of either the Neuroglian CAM, the FGF receptor coded by the gene heartless, or the EGF receptor coded by DER display a similar phenotype of abnormal substrate selection and axon guidance by peripheral sensory neurons. Moreover, neuroglian loss-of-function phenotype can be suppressed by the expression of gain-of-function conditions of heartless or DER. The results are consistent with a scenario where the activity of these receptor tyrosine kinases is controlled by Neuroglian at choice points where sensory axons select between alternative substrates for extension.