Cryptococcus neoformans in bird excreta in the city zoo of Cali,Colombia

The presence of Cryptococcus neoformans was studied in bird excreta and in the air circulating in and around bird cages in the City Zoo of Cali, Colombia, between August 1994 and April 1995, using a sunflower seed agar culture medium for fungus isolation. A total of 380 samples was studied, 110 from droppings and 270 from Petri dishes placed inside(148) and outside (122) the cages. C. neoformansvar neoformans was found in only two cases, one from bird excreta (0.9%) and the other from air inside a cage (0.7%). The former positive sample was collected from the cracks of a dead tree where two crested caracaras (Polyborusplancus) roosted; the feces were dry, accumulated,and with a pH of 6. The other positive sample was found inside the cage of these birds; however, samples taken in a dispersion study at 0.5, 1, 5 and 10 m around this cage were all negative. It appears that this low isolation rate is due to adequate cleaning and disinfection procedures used in the city zoo of Cali.This revised version was published online in October 2005 with corrections to the Cover Date.     

New caffeic acid esters from Plazia daphnoides

Two new 3,4 dihydroxycinnamic acid esters have been isolated from Plazia daphnoides. The structures were elucidated by NMR spectroscopy.     

Highly protective E2-CSFV vaccine candidate produced in the mammary gland of adenoviral transduced goats

Classical swine fever virus is the etiological agent of the most economically important highly contagious disease of swine worldwide. E2 is the major envelope glycoprotein present as a homodimer on the outer surface of the virus and represents an important target for the induction of neutralizing immune response against the viral infection. The E2 extracellular domain was expressed in the milk of adenoviral transduced goats at the highest level about 1.2g/L. The recombinant glycoprotein was purified from clarified serum milk by a single metal chelate affinity chromatography step, as a homodimer of approximately 100kDa and purity over 98%. Glycosylation analysis showed the presence of oligomannoside, hybrid and complex type N-glycans, attached to the recombinant E2. The capacity of goat milk-derived E2 antigen to protect pigs from both classical swine fever clinical signs and viral infection was assessed in a vaccination and challenge trial. The immunized pigs became protected after challenge with 10(5) LD(50) of a highly pathogenic CSFV strain. In the context of veterinary vaccines, this expression system has the advantages that the recombinant antigen could be harvested in about 48h after adenoviral transduction with expression levels in the range of g/L. This approach may turn into a scalable expression system for the assessment and production of veterinary vaccines.     

Antifeedant C20 diterpene alkaloids

We have tested the insect antifeedant and toxic activity of 21 C20 diterpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata. The antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata and S. littoralis were the rearranged form of hetisine (20; EC50 = 1.7 microg/cm2) and 19-oxodihydroatisine (9; EC50 = 0.1 microg/cm2), resp. Glandulosine (8) moderately affected orally injected S. littoralis larvae. A few compounds (13-oxocardiopetamine (4), 9, and atisinium chloride (13)) had cytotoxic effects to insect-derived Sf9 cells with varying degrees of selectivity with respect to mammalian CHO cells. Compounds 4 and 15,22-O-diacetyl-19-oxodihydroatisine (10) increased Trypanosoma cruzi mortality. Our results support the plant protective role of C20 diterpenoid alkaloids and open a new field for parasite control strategies.     

Leishmania repression of host translation through mTOR cleavage is required for parasite survival and infection

The protozoan parasite Leishmania alters the activity of its host cell, the macrophage. However, little is known about the effect of Leishmania infection on host protein synthesis. Here, we show that the Leishmania protease GP63 cleaves the mammalian/mechanistic target of rapamycin (mTOR), a serine/threonine kinase that regulates the translational repressor 4E-BP1. mTOR cleavage results in the inhibition of mTOR complex 1 (mTORC1) and concomitant activation of 4E-BP1 to promote Leishmania proliferation. Consistent with these results, pharmacological activation of 4E-BPs with rapamycin, results in a dramatic increase in parasite replication. In contrast, genetic deletion of 4E-BP1/2 reduces parasite load in macrophages ex vivo and decreases susceptibility to cutaneous leishmaniasis in vivo. The parasite resistant phenotype of 4E-BP1/2 double-knockout mice involves an enhanced type I IFN response. This study demonstrates that Leishmania evolved a survival mechanism by activating 4E-BPs, which serve as major targets for host translational control.     

Rv1268c protein peptide inhibiting Mycobacterium tuberculosis H37Rv entry to target cells

Tuberculosis (TB) remains one of the most worrying infectious diseases affecting public health around the world; 8.7 million new TB cases were reported in 2011. The search for an Mycobacterium tuberculosis H37Rv protein sequence which is functionally important in host-pathogen interaction has been proposed for developing a new vaccine which will allow efficient and safe control of the spread of this disease.The present study thus reports the results obtained for the Rv1268c protein described in the M. tuberculosis H37Rv genome as a hypothetical unknown, probably secreted, protein based on a highly robust, specific, sensitive and functional approach to the search for potential epitopes to be included in an anti-tuberculosis vaccine. Rv1268c presence was determined by immunoblotting after obtaining polyclonal sera against mycobacterial total sonicate or subcellular fractions. Such sera were used in electron immunomicroscopy (EIM) for confirming protein localisation on the M. tuberculosis envelop by recognising colloidal gold-labelled immunoglobulin. Screening assays revealed the presence of two sequences having high binding activity: one binding A549 alveolar epithelial cells (¹⁴¹TGMAALEQYLGSGHAVIVSI¹⁶⁰) and other binding U937 monocyte-derived macrophages (²¹AVALGLASPADAAAGTMYGD⁴⁰). Such sequences’ ability to inhibit mycobacterial entry during in vitro assays was analysed. The structure of synthetic peptides binding to target cells was also determined, bearing in mind the structure–function relationship. These results, together with those obtained for other proteins, have been involved in selecting peptides which might be included in a subunit-based anti-tuberculosis vaccine.     

Risk factors for asthma and allergy associated with urban migration: background and methodology of a cross-sectional study in Afro-Ecuadorian school children in Northeastern Ecuador (Esmeraldas-SCAALA Study)

Background

This study examined the attitudes and actions of 3415 physician-recruited adults aged ≥ 16 years with asthma in eleven countries who were prescribed regular maintenance therapy with inhaled corticosteroids or inhaled corticosteroids plus long-acting β₂-agonists.

Methods

Structured interviews were conducted to assess medication use, asthma control, and patients' ability to recognise and self-manage worsening asthma.

Results

Despite being prescribed regular maintenance therapy, 74% of patients used short-acting β₂-agonists daily and 51% were classified by the Asthma Control Questionnaire as having uncontrolled asthma. Even patients with well-controlled asthma reported an average of 6 worsenings/year. The mean period from the onset to the peak symptoms of a worsening was 5.1 days. Although most patients recognised the early signs of worsenings, the most common response was to increase short-acting β₂-agonist use; inhaled corticosteroids were increased to a lesser extent at the peak of a worsening.

Conclusion

Previous studies of this nature have also reported considerable patient morbidity, but in those studies approximately three-quarters of patients were not receiving regular maintenance therapy and not all had a physician-confirmed diagnosis of asthma. This study shows that patients with asthma receiving regular maintenance therapy still have high levels of inadequately controlled asthma. The study also shows that patients recognise deteriorating asthma control and adjust their medication during episodes of worsening. However, they often adjust treatment in an inappropriate manner, which represents a window of missed opportunity.     

Incidence of Human Taenia solium Larval Infections in an Ecuadorian Endemic Area: Implications for Disease Burden Assessment and Control

Background

Human cysticercosis is a zoonotic disease causing severe health disorders and even death. While prevalence data become available worldwide, incidence rate and cumulative incidence figures are lacking, which limits the understanding of the Taenia solium epidemiology.

Methodology/Principal findings

A seroepidemiological cohort study was conducted in a south-Ecuadorian community to estimate the incidence rate of infection with and the incidence rate of exposure to T. solium based on antigen and antibody detections, respectively. The incidence rate of infection was 333.6 per 100,000 person-years (95% CI: [8.4–1,858] per 100,000 person-years) contrasting with a higher incidence rate of exposure 13,370 per 100,000 person-years (95% CI: [8,730–19,591] per 100,000 person-years). The proportion of infected individuals remained low and stable during the whole study year while more than 25% of the population showed at least one antibody seroconversion/seroreversion during the same time period.

Conclusions/Significance

Understanding the transmission of T. solium is essential to develop ad hoc cost-effective prevention and control programs. The estimates generated here may now be incorporated in epidemiological models to simulate the temporal transmission of the parasite and the effects of control interventions on its life cycle. These estimates are also of high importance to assess the disease burden since incidence data are needed to make regional and global projections of morbidity and mortality related to cysticercosis.     

Anaerobic digestion of municipal solid waste and agricultural waste and the effect of co-digestion with dairy cow manure

Anaerobic digestion of dairy cow manure (CM), the organic fraction of municipal solid waste (OFMSW), and cotton gin waste (CGW) was investigated with a two-phase pilot-scale anaerobic digestion (AD) system. The OFMSW and CM were digested as single wastes and as combined wastes. The single waste digestion of CM resulted in 62m(3) methane/ton of CM on dry weight basis. The single waste digestion of OFMSW produced 37m(3) methane/ton of dry waste. Co-digestion of OFMSW and CM resulted in 172m(3) methane/ton of dry waste. Co-digestion of CGW and CM produced 87m(3) methane/ton of dry waste. Comparing the single waste digestions with co-digestion of combined wastes, it was shown that co-digestion resulted in higher methane gas yields. In addition, co-digestion of OFMSW and CM promotes synergistic effects resulting in higher mass conversion and lower weight and volume of digested residual.     

A Scoping Review and Prevalence Analysis of Soil-Transmitted Helminth Infections in Honduras

Background

Honduras is endemic for soil-transmitted helminth (STH) infections, but critical information gaps still remain on the prevalence and intensity of these infections as well as on their spatial distribution at subnational levels.

Objectives

Firstly, to review the research activity on STH infections in Honduras and secondly, to carry out a national prevalence analysis and map the geographical distribution of these infections in children.

Methods

A systematic search was conducted of the published and grey literature to identify scientific work on the impact and prevalence of STH infections done between May 1930 and June 30, 2012. International databases and Honduran journals were searched. Grey literature was gleaned from local libraries and key informants. Select studies conducted between 2001 and 2012 were used to produce prevalence maps and to investigate association between STH prevalence and socio-economic and environmental factors.

Results

Of 257 identified studies, 211 (21.4% peer-reviewed) were retained for analysis and categorized as clinical research (10.9%), treatment efficacy studies (8.1%) or epidemiological studies (81%). Prevalence analysis and geographical mapping included 36 epidemiological studies from Honduras''s 18 departments and 23% of its municipalities. Overall STH prevalence was >50% in 40.6% of municipalities. Prevalences above 20% for each trichuriasis, ascariasis, and hookworm infection were found in 68%, 47.8%, and 7.2% of studied municipalities, respectively. Municipalities with lower human development index, less access to of potable water, and with higher annual precipitation showed higher STH prevalences.

Conclusions

This is the first study to provide a comprehensive historic review of STH research activity and prevalence in Honduras, revealing important knowledge gaps related to infection risk factors, disease burden, and anti-parasitic drug efficacy, among others. Our decade-long prevalence analysis reveals geographical differences in STH prevalence and these findings suggest that differential intervention strategies might be necessary in Honduras for the control of these infections.