208 research outputs found
The efficacy of last-line and experimental antimicrobials against Stenotrophomonas maltophilia and the characterisation of resistant mutant
Human myiasis in Ecuador.
We review epidemiological and clinical data on human myiasis from Ecuador, based on data from the Ministry of Public Health (MPH) and a review of the available literature for clinical cases. The larvae of four flies, Dermatobia hominis, Cochliomyia hominivorax, Sarcophaga haemorrhoidalis, and Lucilia eximia, were identified as the causative agents in 39 reported clinical cases. The obligate D. hominis, causing furuncular lesions, caused 17 (43.5%) cases distributed along the tropical Pacific coast and the Amazon regions. The facultative C. hominivorax was identified in 15 (38%) clinical cases, infesting wound and cavitary lesions including orbital, nasal, aural and vaginal, and occurred in both subtropical and Andean regions. C. hominivorax was also identified in a nosocomial hospital-acquired wound. Single infestations were reported for S. haemorrhoidalis and L. eximia. Of the 39 clinical cases, 8 (21%) occurred in tourists. Ivermectin, when it became available, was used to treat furuncular, wound, and cavitary lesions successfully. MPH data for 2013–2015 registered 2,187 cases of which 54% were reported in men; 46% occurred in the tropical Pacific coast, 30% in the temperate Andes, 24% in the tropical Amazon, and 0.2% in the Galapagos Islands. The highest annual incidence was reported in the Amazon (23 cases/100,000 population), followed by Coast (5.1/100,000) and Andes (4.7/100,000). Human myiasis is a neglected and understudied ectoparasitic infestation, being endemic in both temperate and tropical regions of Ecuador. Improved education and awareness among populations living in, visitors to, and health personnel working in high-risk regions, is required for improved epidemiological surveillance, prevention, and correct diagnosis and treatment
Facial recognition system for people with and without face mask in times of the covid-19 pandemic
In the face of the COVID-19 pandemic, the World Health Organization (WHO) declared the use of a face mask as a mandatory biosafety measure. This has caused problems in current facial recognition systems, motivating the development of this research. This manuscript describes the development of a system for recognizing people, even when they are using a face mask, from photographs. A classification model based on the MobileNetV2 architecture and the OpenCv''s face detector is used. Thus, using these stages, it can be identified where the face is and it can be determined whether or not it is wearing a face mask. The FaceNet model is used as a feature extractor and a feedforward multilayer perceptron to perform facial recognition. For training the facial recognition models, a set of observations made up of 13, 359 images is generated; 52.9% images with a face mask and 47.1% images without a face mask. The experimental results show that there is an accuracy of 99.65% in determining whether a person is wearing a mask or not. An accuracy of 99.52% is achieved in the facial recognition of 10 people with masks, while for facial recognition without masks, an accuracy of 99.96% is obtained. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Novel mechanisms of efflux-mediated levofloxacin resistance and reduced amikacin susceptibility in Stenotrophomonas maltophilia
Fluoroquinolone resistance in Stenotrophomonas maltophilia is multifactorial, but the most significant factor is overproduction of efflux pumps, particularly SmeDEF, following mutation. Here, we report that mutations in the glycosyl transferase gene smlt0622 in S. maltophilia K279a mutant K M6 cause constitutive activation of SmeDEF production, leading to elevated levofloxacin MIC. Selection of a levofloxacin-resistant K M6 derivative, K M6 LEV(r), allowed identification of a novel two-component regulatory system, Smlt2645/6 (renamed SmaRS). The sensor kinase Smlt2646 (SmaS) is activated by mutation in K M6 LEV(r) causing overproduction of two novel ABC transporters and the known aminoglycoside efflux pump SmeYZ. Overproduction of one ABC transporter, Smlt1651-4 (renamed SmaCDEF), causes levofloxacin resistance in K M6 LEV(r). Overproduction of the other ABC transporter, Smlt2642/3 (renamed SmaAB), and SmeYZ both contribute to the elevated amikacin MIC against K M6 LEV(r). Accordingly, we have identified two novel ABC transporters associated with antimicrobial drug resistance in S. maltophilia and two novel regulatory systems whose mutation causes resistance to levofloxacin, clinically important as a promising drug for monotherapy against this highly resistant pathogen
Las metáforas del oĂdo: la sonoridad en El sonido de tus pasos, de Francisco Granizo Ribadeneira
En su libro A la escucha, el filĂłsofo Jean-Luc Nancy propone que el sentido en la literatura contemporánea no es neutro, ni áfono, si no que la escritura del siglo XX busca, sobre todo, la resonancia del sentido más allá de sĂ mismo. Aunque estĂ© escrito tiene una voz, nos dice Nancy, y será la bĂşsqueda de esta voz en la poesĂa de Granizo lo que guĂa este estudio. Un sentido que resuena es lo que encontramos en la obra de Francisco Granizo. La voz de aquello que Granizo escribe, comentado por Ă©l mismo en su ensayo De la poesĂa, es una voz musical. La mĂşsica de sus versos destruye la afonĂa del sentido y es ella, en distintos niveles, el sentido. En el primer capĂtulo analizaremos la personal mitologĂa musical de Francisco Granizo, desarrollada en el ensayo De la poesĂa. Y en los dos siguientes capĂtulos, siguiendo las reflexiones de “El acto de escuchar” y Fragmentos de un discurso amoroso, interpretaremos los versos de Granizo a la luz de las ideas de Roland Barthes y Roland Havas. AsĂ, pasaremos de los sonidos que nos indican la presencia del amado y de la voz, a la expansiĂłn del sentido en el ritmo de los versos, para terminar con el dibujo de las dos metáforas del oĂdo claves para comprender la obra de Francisco Granizo. Por ser su Ăşltimo poemario publicado en vida, nos concentraremos en El sonido de tus pasos para la aplicaciĂłn de esta metodologĂa sonora. De esta manera, esta tesis se propone evidenciar las posibilidades de la sonoridad para resonar el sentido más allá de las palabras
A comparison of Kato-Katz technique to three other methods for diagnosis of Amphimerus spp. liver fluke infection and the prevalence of infection in Chachi Amerindians of Ecuador
Background
Recently, a high prevalence of infection by the liver fluke Amphimerus spp. has been documented
in the Chachi Amerindians of Ecuador. For diagnosis, no studies exist that compare
the sensitivity of different coproparasitological detection techniques. The present study compares
the Kato-Katz technique with three other coproparasitological methods for detecting
eggs of Amphimerus in stools, as well as determines the prevalence of infection in Chachi
residents in a Tropical rain forest area in the northwest coast of Ecuador.
Methodology/Results
A total of 105 samples, utilizing the Kato-Katz technique (KK), the spontaneous sedimentation
technique in tube (SSTT), the formalin-ether concentration technique (FEC), and direct
smear microscopy (DM), were examined. Combining the four methods (fixed ÂŞgoldÂş standard),
38 samples were positive with a prevalence of infection of 36.2%. The sensitivities of
individual methods were 71%, 58%, 50% and 3% for KK, SSTT, FEC, and DM respectively.
Our results indicated that KK alone had the best performance, detecting 27 (71%) of the 38
positive samples. The combination of KK and SSTT detected amphimeriasis in 36 (95%)
samples, and KK and FEC in 31 (82%) samples.
Conclusions
DM showed the lowest sensitivity, which raises concern for its value, because it is the standard
technique for stool examination for detection of parasites in both public and private
laboratories in Ecuador. SSTT alone detected eggs in 22 samples (58%) and would be recommended
for field studies because of its simplicity. Performing two techniques on a single
sample enhances the detection of Amphimerus infection. Its sensitivity is relative to a fixed ÂŞgoldÂş standard, determined as the combined results of the four techniques performed. This
study confirms the high prevalence of human infection by Amphimerus in the indigenous
Chachi group where the first human cases were described.CUP 91750000.0000.374072KAKENHI: Grant No.16H0582
Hypolobocera guayaquilensis (Decapoda: Pseudothelphusidae): A New Crab Intermediate Host of Paragonimus mexicanus in ManabĂ Province, Ecuador
To determine that Paragonimus sp. is actively transmitted in a tropical area of the Pacific region of Ecuador where human cases of pulmonary paragonimiasis have recently been documented, a total of 75 freshwater crabs were collected from 2 different streams in the Pedernales area of ManabĂ Province, Ecuador. All collected crabs were identified as Hypolobocera guayaquilensis based on morphological characteristics of the male gonopods. The hepatopancreas of each crab was examined by compressing it between 2 glass plates followed by observation under a stereomicroscope. Excysted Paragonimus metacercariae were detected in 39 (52.0%) crabs and their densities varied from 1 to 32 per infected crab. There was a positive relationship between crab size and metacercarial density. Sequences of the second internal transcribed spacer region of the ribosomal RNA gene of the Paragonimus metacercariae obtained in this study were identical to those of Paragonimus mexicanus deposited in the DDBJ/EMBL/GenBank database. Thus, the present study is the first to confirm that the crab species H. guayaquilensis is the second intermediate host of P. mexicanus in ManabĂ Province, Ecuador. Because this crab might be the possible source of human infections in this area, residents should pay attention to improper crab-eating habits related with a neglected parasitic disease, i.e., paragonimiasis
Leishmania species and clinical characteristics of Pacific and Amazon cutaneous leishmaniasis in Ecuador and determinants of health-seeking delay: a cross-sectional study
Ecuador; Leishmaniasis; PhylogenyEquador; Leishmaniosi; FilogèniaEcuador; Leishmaniosis; FilogeniaBackground
Cutaneous Leishmaniasis (CL) affects up to 5.000 people in Ecuador each year. L. guyanensis and L. braziliensis are the most common of the eight CL-causing Leishmania species. Earlier CL research concentrated on the easily accessible Pacific region. This study aims to describe the Leishmania species in Pacific and Amazon ecoregions, to analyze regional differences in CL patient clinical presentation, and to identify determinants of health-seeking delay.
Methods
All cases in this cross-sectional study were diagnosed using smear slide microscopy, PCR, or both. Cytochrome B gene sequencing was used to identify the causative Leishmania species in qPCR-positive samples.
Results
This study included 245 patients, with 154 (63%) infected in the Pacific region and 91 (37%) infected in the Amazon. Causative Leishmania species were identified in 135 patients (73% of qPCR positives). L. guyanensis was identified in 76% (102/135) of the samples and L. braziliensis in 19% (26/135). The Pacific region had a low prevalence of 6% (5/89) of L. braziliensis. For the first time, we report L. guyanensis from the central Amazon, L. braziliensis from the northern Pacific, and L. lainsoni from both the central Amazon and northern Pacific. Amazon cases had a longer median health-seeking delay in months (2.0, IQR 3.0) than Pacific cases (1.0, IQR 1.5). Prolonged health-seeking delay was associated with older age, Amerindian ethnicity, infection at lower altitudes, non-ulcerative lesions, and lesions on the lower limbs.
Conclusions
In the Pacific region, health-seeking delay is relatively short and L. braziliensis prevalence remains low. Limited access to health care and stigma might explain the prolonged health-seeking delay in the Amazon. We recommend larger studies on the distribution of Leishmania species in Amazon CL cases and additional regional research into diagnostic test accuracy. Furthermore, the determinants of health-seeking delay in Ecuador should be investigated further.Foundation Latin Link Nederland provided funding for the current study
A new sesquiterpene essential oil from the native andean species jungia rugosa less (Asteraceae): Chemical analysis, enantiomeric evaluation, and cholinergic activity
As part of a project devoted to the phytochemical study of Ecuadorian biodiversity, new essential oils are systematically distilled and analysed. In the present work, Jungia rugosa Less (Asteraceae) has been selected and some wild specimens collected to investigate the volatile fraction. The essential oil, obtained from fresh leaves, was analysed for the first time in the present study. The chemical composition was determined by gas chromatography, coupled to mass spectrometry (GC-MS) for qualitative analysis, and to flame ionization detector (GC-FID) for quantitation. The calculation of relative response factors (RRF), based on combustion enthalpy, was carried out for each quantified component. Fifty-six compounds were identified and quantified in a 5% phenyl-polydimethylsiloxane non-polar column and 53 compounds in a polyethylene glycol polar column, including four undetermined compounds. The main feature of this essential oil was the exclusive sesquiterpenes content, both hydrocarbons (74.7% and 80.4%) and oxygenated (8.3% and 9.6%). Major constituents were: γ-curcumene (47.1% and 49.7%) and β-sesquiphellandrene (17.0% and 17.9%), together with two abundant undetermined oxygenated sesquiterpenes, whose abundance was 6.7–7.2% and 4.7–3.3%, respectively. In addition, the essential oil was submitted to enantioselective evaluation in two β-cyclodextrin-based enantioselective columns, determining the enantiomeric purity of a minor component (1S,2R,6R,7R,8R)-(+)-α-copaene. Finally, the AChE inhibition activity of the EO was evaluated in vitro. In conclusion, this volatile fraction is suitable for further investigation, according to two main lines: (a) the purification and structure elucidation of the major undetermined compounds, (b) a bio-guided fractionation, intended to investigate the presence of new sesquiterpene AChE inhibitors among the minor components
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