Mushrooms to live or die: toxicity of some Basidiomycota using Artemia franciscana.

Consumption of wild mushrooms has increased in recent years; however, not all of them are edible and there is no precise information on those that may cause poisoning. Therefore, studies to obtain data about their toxicity are needed. For this purpose, we used the brine shrimp Artemia franciscana, a crustacean employed in toxicity tests and with wide application in the toxin detection, including mycotoxins. Mushrooms were collected in the state of Jalisco, Mexico, with which aqueous extracts were prepared. Dilutions of the stock solution of each extract were made to final concentrations of 50, 100, 250, 500, and 1000 µg/mL. Potassium dichromate (PD) was used as positive control and artificial seawater as negative control. The median lethal dose (LD50) of extracts on nauplii of A. franciscana was calculated. The aqueous extracts obtained from Amanita amerivirosa, A. muscaria, Chlorophyllum molybdites, and Leucopaxillus amarus showed a LD50 < 70 µg/mL, similar to PD (LD50 = 37 µg/mL). This is the first indication of the probable toxicity of Leucopaxillus amarus in humans. Cantharellus cibarius and Scleroderma texense caused the lower toxicity to the nauplii. The brine shrimp bioassay was effective in evaluating the toxicity of Basidiomycota. Scleroderma texense has been reported to be toxic, but it was not for this crustacean nauplii, and probably not to humans either, as recent literature has reported.

Physical therapy in Down syndrome: systematic review and meta-analysis.

BACKGROUND: Down syndrome is the most common chromosomal abnormality, with a worldwide incidence of around 0.1% in live births. It is related to several conditions in which the physical therapy could take action-preventing co-morbidities. This study aims to evaluate the effectiveness of physical therapy in Down syndrome, to know and compare the effectiveness of different physical therapy interventions in this population. METHODS: A systematic review and a meta-analysis of randomised controlled trials were conducted. The search was performed during June 2018 in the following databases: PubMed, Web of Science, Physiotherapy Evidence Database and Scopus. The studies were selected using predefined inclusion and exclusion criteria. The Physiotherapy Evidence Database scale evaluated the quality of the methods used in the studies. Subsequently, the data were extracted, and statistical analysis was performed when possible. RESULTS: A total of 27 articles were included, of which nine contributed information to the meta-analysis. Statistical analysis showed favourable results for the strength of upper and lower limbs [standardised mean difference (SMD) = 1.46; 95% confidence interval (CI): (0.77-2.15); and SMD = 2.04; 95% CI: (1.07-3.01)] and mediolateral oscillations of balance [SMD = -3.30; 95% CI: (-5.34 to -1.26)]. CONCLUSIONS: The results show the potential benefit of certain types of physical therapy interventions, specifically in strength and balance, in people with Down syndrome. There are still many aspects to clarify and new lines of research.

Modified Synthesis Strategies for the Stabilization of low n Tin O2n-1 Magnéli Phases.

Titanium reduced oxides TiO2-x occupy, since long time, a prominent place on the landscape of binary metal oxides because of their intriguing ability to form extended defects that affect both the formation of new superlattices and different electronic behaviours. Related to these features, a wide range of practical applications has been achieved. Moved by the conviction of the great potential of understanding the influence of the reactivity, compositional variations and size effects on their functional properties, the aim of this personal account is the optimization of a recently developed strategy for the stabilization of low n Tin O2n-1 terms. In particular, we will focus on the Ti4 O7 composition as well as the incorporation of transition metals, like Mn, in order to deal with new reduced Magnéli phases.

The dissolution and biological effects of silver nanoparticles in biological media.

Silver ions and silver nanoparticles have a well-known biological effect that typically occurs in biological or environmental media of complex composition. Silver nanoparticles release silver ions if oxidizing species like molecular oxygen or hydrogen peroxide are present. The presence of glucose as a model for reducing sugars has only a small effect on the dissolution rate. In the presence of chloride ions, precipitation of silver chloride nanoparticles occurs. At physiological salt concentrations, no precipitation of silver phosphate occurs as the precipitation of silver chloride always occurs first. If the surface of a silver nanoparticle is passivated by cysteine, the dissolution is quantitatively inhibited. Upon immersion of silver nanoparticles in pure water for 8 months, leading to about 50% dissolution, no change in the surface was observed by transmission electron microscopy. A model for the dissolution was derived from immersion and dissolution experiments in different media and from high-resolution transmission electron microscopy. A literature survey on the available data on the dissolution of silver nanoparticles showed that only qualitative trends can be identified as the nature of the nanoparticles and of the immersion medium are practically never comparable. The dissolution effects were confirmed by cell culture experiments (human mesenchymal stem cells and neutrophil granulocytes) where silver nanoparticles that were stored under argon had a clearly lower cytotoxicity than those stored under air. They also led to a less formation of reactive oxygen species (ROS). This underscores that silver ions are the toxic species.

Poly(methyl methacrylate) coating of soft magnetic amorphous and crystalline Fe,Co-B nanoparticles by chemical reduction.

The structural and magnetic properties of a collection of nanoparticles coated by Poly(methyl methacrylate) through a wet chemical synthesis have been investigated. The particles display either an amorphous (M = Fe, Co) M-B arrangement or a mixed structure bcc-Fe and fcc-Co + amorphous M-B. Both show the presence of a metal oxi-hydroxide formed in aqueous reduction. The organic coating facilitates technological handling. The cost-effective synthesis involves a reduction in a Poly(methyl methacrylate) aqueous solution of iron(II) or cobalt(II) sulphates (< 0.5 M) by sodium borohydride (< 0.5 M). The particles present an oxidized component, as deduced from X-ray diffraction, Mössbauer and Fe- and Co K-edge X-ray absorption spectroscopy and electron microscopy. For the ferrous alloys, this Fe-oxide is alpha-goethite, favoured by the aqueous solution. The Poly(methyl methacrylate) coating is confirmed by Fourier transform infrared spectroscopy. In pure amorphous core alloys there is a drastic change of the coercivity from bulk to around 30 Oe in the nanoparticles. The mixed structured alloys also lie in the soft magnetic regime. Magnetisation values at room temperature range around 100 emu/g. The coercivity stems from multidomain particles and their agglomeration, triggering the dipolar interactions.

[Neonatal bacterial meningitis in a tertiary treatment center]. / Meningitis bacteriana neonatal en una institución de tercer nivel de atención.

OBJECTIVE: To determine incidence, etiologic agents and clinical manifestations of bacterial meningitis in patients hospitalized in the newborn ward at the Hospital Infantil de Mexico in Mexico City and establish the incidence of meningitis in newborns admitted with respiratory distress syndrome (RDS) and determine how often blood cultures are negative in bacterial meningitis in this population. METHODS: Retrospective chart review of patients with bacterial meningitis admitted to our hospital. STUDY PERIOD: January 1990-July 1995. RESULTS: There were 959 admissions to the neonatal intensive care unit (NICU). The overall incidence of bacterial meningitis was 32.3/1000 admissions; however, among 170 patients with RDS, [corrected] meningitis was detected in one (5.9/1000 RDS patients). Of the 31 patients with bacterial meningitis, 10 were preterm (PT) and 21 term (T). In the cerebrospinal fluid (CSF) isolates, there was a predominance of gram negative rods (n: 19; 61%). Clinical findings associated to meningitis were non-specific and there were no differences between PT and T infants. From 31 patients, 19 had negative blood cultures at the time of diagnosis (61%). Mortality associated to bacterial meningitis was [corrected] 40% and 23%, for PT and T, respectively (p = NS). CONCLUSIONS: The incidence of bacterial meningitis in the study population was high. Most isolates in CSF were gram-negative rods. Clinical findings in meningitis were non-specific and there were no differences between PT and T. Most of the patients (61%) had negative blood cultures at the time of diagnosis.

[Frequency of Toxocara cati eggs in domestic cats in Mexico City and the State of Mexico]. / Frecuencia de hallazgo de huevos de Toxocara cati en gatos domésticos de la Ciudad de México y el Estado de México.

Toxocariosis is a zoonosis which has been widely studied in dogs. However, not much is known about this parasitosis in cats. The aim of the present work was to determine the frequency of Toxocara cati in domestic cats in Mexico City and the State of Mexico. Feces of 660 domestic cats were studied by the Faust concentration-floating test; 401 samples were from cats living in Mexico City of which 308 lived in houses and 93 in apartments; 231 were from urban areas of the State of Mexico and 28 from a rural area of the same state. The total frequency of T. cati eggs obtained from domestic cats in Mexico City was 42.9%; in cats living in apartments it was 18.3% and in cats living in houses it was 50.3%. In domestic cats from the State of Mexico, T. cati frequency was 36.4% in the urban and 21.4% in the rural areas. We consider that toxocariosis frequency observed at the two studied sites is high and that the need to prevent dissemination of the infectious forms of T. cati is urgent, as is the necessity of informing the population of the risk of living with T. cati parasited animals and of the anatomopathological alterations caused by T. cati in man.

[Infection by Toxoplasma gondii in children with infantile cerebral palsy]. / Infección por Toxoplasma gondii en niños con parálisis cerebral infantil.

An analytic relationship between positivity of the indirect immunofluorescent test (IIFT) for toxoplasmosis and clinical findings in a population of 328 children with cerebral infantile palsy (CIP) was performed. Children were distributed by age in one of four groups: I (0-2 years); II (3-6 years); III (7-12 years) and IV (13-18 years). One control group of 168 children with no PCI clinical findings was included. 125 sera were positive at 1:64 dilutions. The study of the binomial mother-child of 40 cases rendered 26 mothers with significant titer values. The majority of positive mothers to IIFT correlated with the youngest children (Groups I, II and III), mainly with group I (70.0%), which showed the highest titer ranges. Correlation between positive IIFT and clinical features was as high as 100.0%.