Ambient synthesis of nanomaterials by in situ heterogeneous metal/ligand reactions

Coordination polymers are ideal synthons in creating high aspect ratio nanostructures, however, conventional synthetic methods are often restricted to batch-wise and costly processes. Herein, we demonstrate a non-traditional, frugal approach to synthesize 1D coordination polymers by in situ etching of zerovalent metal particle precursors. This procedure is denoted as the heterogeneous metal/ligand reaction and was demonstrated on Group 13 metals as a proof of concept. Simple carboxylic acids supply the etchant protons and ligands for metal ions (conjugate base) in a 1 : 1 ratio. This scalable reaction produces a 1D polymer that assembles into high-aspect ratio 'nanobeams'. We demonstrate control over crystal structure and morphology by tuning the: (i) metal center, (ii) stoichiometry and (iii) structure of the ligands. This work presents a general scalable method for continuous, heat free and water-based coordination polymer synthesis

Epidemiology of venous leg ulcers in primary health care: Incidence and prevalence in a health centre-A time series study (2010-2014)

The aims of the study were to describe and analyse the temporal trend of the prevalence and incidence of venous leg ulcers (VLU) over the years 2010 to 2014, to determine healing times and temporal trends in the study period, and to evaluate related aspects such as the use of the Ankle-Brachial Pressure Index (ABPI) in a primary care health centre. This was a retrospective study based on a time series (years 2010-2014) of the prevalence and incidence of VLUs in people aged over 40 years in a primary care centre in Barcelona City. We reviewed 3920 electronic health records selecting patients, per year (2010-2014), with VLUs based on the ICD-10 diagnoses. For prevalence, we took into account any patient with an active VLU in the year of study. For incidence, we took into account patients with a new VLU in the year of study. A descriptive analysis was carried out based on each of the collected variables. The variables were examined according to the years of study (time series) by one-factor analysis of variance (ANOVA) or Kruskal?Wallis non-parametric test, as appropriate. A survival analysis by Kaplan?Meier curves and log-rank test was also performed. A total of 139 patients met the VLU criteria. Among them, only 79.2% were classified as having a VLU and had a correct ICD diagnosis. The prevalence and incidence increased over the years, doubling in patients aged over 65 years. Incidence increased from 0.5 new cases per 1000 people/ year in 2010 to 1 new case for every 1000 people/year in 2014. Moreover, the prevalence ranged between 0.8 and 2.2 patients with VLU for every 1000 people/ year. During the study period, a total of 84.2% of the VLUs healed (117/139 VLU). Regarding average annual time to healing, the trend indicates that lesions took less time to heal (Kruskal?Wallis test, P = 0.004), ranging between 453,9 weeks in 2005 to 19 weeks in 2014. The use of ABPI also evolved and was found to be increasingly performed prior to the appearance of the lesion. The epidemiological profile of people affected by VLUs continues to be, mainly, that of women of an advanced age, over 70 years. The frequency of VLU occurrence rose continually over the years, but healing took less time, and use of ABPI improved. Assigning a reference nurse in the wounds unit and the organisational structure around this problem may have an influence on improving care and the approach to these types of lesions

Haemoglobin C and S Role in Acquired Immunity against Plasmodium falciparum Malaria

A recently proposed mechanism of protection for haemoglobin C (HbC; β6Glu→Lys) links an abnormal display of PfEMP1, an antigen involved in malaria pathogenesis, on the surface of HbC infected erythrocytes together with the observation of reduced cytoadhesion of parasitized erythrocytes and impaired rosetting in vitro. We investigated the impact of this hypothesis on the development of acquired immunity against Plasmodium falciparum variant surface antigens (VSA) encoding PfEMP1 in HbC in comparison with HbA and HbS carriers of Burkina Faso. We measured: i) total IgG against a single VSA, A4U, and against a panel of VSA from severe malaria cases in human sera from urban and rural areas of Burkina Faso of different haemoglobin genotypes (CC, AC, AS, SC, SS); ii) total IgG against recombinant proteins of P. falciparum asexual sporozoite, blood stage antigens, and parasite schizont extract; iii) total IgG against tetanus toxoid. Results showed that the reported abnormal cell-surface display of PfEMP1 on HbC infected erythrocytes observed in vitro is not associated to lower anti- PfEMP1 response in vivo. Higher immune response against the VSA panel and malaria antigens were observed in all adaptive genotypes containing at least one allelic variant HbC or HbS in the low transmission urban area whereas no differences were detected in the high transmission rural area. In both contexts the response against tetanus toxoid was not influenced by the β-globin genotype. These findings suggest that both HbC and HbS affect the early development of naturally acquired immunity against malaria. The enhanced immune reactivity in both HbC and HbS carriers supports the hypothesis that the protection against malaria of these adaptive genotypes might be at least partially mediated by acquired immunity against malaria

Effects of an invasive forest pathogen on abundance of ticks and their vertebrate hosts in a California Lyme disease focus

Invasive species, including pathogens, can have important effects on local ecosystems, including indirect consequences on native species. This study focuses on the effects of an invasive plant pathogen on a vertebrate community and Ixodes pacificus, the vector of the Lyme disease pathogen (Borrelia burgdorferi) in California. Phytophthora ramorum, the causative agent of sudden oak death, is a non-native pathogen killing trees in California and Oregon. We conducted a multi-year study using a gradient of SOD-caused disturbance to assess the impact on the dusky-footed woodrat (Neotoma fuscipes) and the deer mouse (Peromyscus maniculatus), two reservoir hosts of B. burgdorferi, as well as the impact on the Columbian black-tailed deer (Odocoileus hemionus columbianus) and the western fence lizard (Sceloporus occidentalis), both of which are important hosts for I. pacificus but are not pathogen reservoirs. Abundances of P. maniculatus and S. occidentalis were positively correlated with greater SOD disturbance, whereas N. fuscipes abundance was negatively correlated. We did not find a change in space use by O. hemionus. Our data show that SOD has a positive impact on the density of nymphal ticks, which is expected to increase the risk of human exposure to Lyme disease all else being equal. A positive correlation between SOD disturbance and the density of nymphal ticks was expected given increased abundances of two important hosts: deer mice and western fence lizards. However, further research is needed to integrate the direct effects of SOD on ticks, for example via altered abiotic conditions with host-mediated indirect effects

The horse

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