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1.
Am J Bot ; 108(2): 236-248, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33586136

RESUMO

PREMISE: Water is the most limiting factor in dryland ecosystems, and plants are adapted to cope with this constraint. Particularly vulnerable are phreatophytic plants from groundwater-dependent ecosystems (GDEs) in regions that have to face water regime alterations due to the impacts of climate and land-use changes. METHODS: We investigated two aspects related to the water-use strategy of a keystone species that dominates one of the few terrestrial GDEs in European drylands (Ziziphus lotus): where it obtains water and how it regulates its use. We (1) evaluated plants' water sources and use patterns using a multiple-isotope approach (δ2 H, δ18 O, and Δ13 C); (2) assessed the regulation of plant water potential by characterizing the species on an isohydric-anisohydric continuum; and (3) evaluated plants' response to increasing water stress along a depth-to-groundwater (DTGW) gradient by measuring foliar gas exchange and nutrient concentrations. RESULTS: Ziziphus lotus behaves as a facultative or partial phreatophyte with extreme anisohydric stomatal regulation. However, as DTGW increased, Z. lotus (1) reduced the use of groundwater, (2) reduced total water uptake, and (3) limited transpiration water loss while increasing water-use efficiency. We also found a physiological threshold at 14 m depth to groundwater, which could indicate maximum rooting length beyond which optimal plant function could not be sustained. CONCLUSIONS: Species such as Z. lotus survive by squandering water in drylands because of a substantial groundwater uptake. However, the identification of DTGW thresholds indicates that drawdowns in groundwater level would jeopardize the functioning of the GDE.


Assuntos
Água Subterrânea , Lotus , Ziziphus , Ecossistema , Água
2.
Oecologia ; 196(4): 1179-1193, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34331567

RESUMO

Water is the main limiting factor for groundwater-dependent ecosystems (GDEs) in drylands. Predicted climate change (precipitation reductions and temperature increases) and anthropogenic activities such as groundwater drawdown jeopardise the functioning of these ecosystems, presenting new challenges for their management. We developed a trait-based analysis to examine the spatiotemporal variability in the ecophysiology of Ziziphus lotus, a long-lived phreatophyte that dominates one of the few terrestrial GDEs of semiarid regions in Europe. We assessed morpho-functional traits and stem water potential along a naturally occurring gradient of depth-to-groundwater (DTGW, 2-25 m) in a coastal aquifer, and throughout the species-growing season. Increasing DTGW and salinity negatively affected photosynthetic and transpiration rates, increasing plant water stress (lower predawn and midday water potential), and positively affected Huber value (sapwood cross-sectional area per leaf area), reducing leaf area and likely, plant hydraulic demand. However, the species showed greater salt-tolerance at shallow depths. Despite groundwater characteristics, higher atmospheric evaporative demand in the study area, which occurred in summer, fostered higher transpiration rates and water stress, and promoted carbon assimilation and water loss more intensively at shallow water tables. This multiple-trait analysis allowed us to identify plant ecophysiological thresholds related to the increase in salinity, but mostly in DTGW (13 m), and in the evaporative demand during the growing season. These findings highlight the existence of tipping points in the functioning of a long-lived phreatophyte in drylands and can contribute to the sustainable management of GDEs in southern Europe, paving the way for further studies on phreatophytic species.


Assuntos
Ecossistema , Água Subterrânea , Mudança Climática , Salinidade , Água
3.
Sensors (Basel) ; 21(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466513

RESUMO

Vegetation generally appears scattered in drylands. Its structure, composition and spatial patterns are key controls of biotic interactions, water, and nutrient cycles. Applying segmentation methods to very high-resolution images for monitoring changes in vegetation cover can provide relevant information for dryland conservation ecology. For this reason, improving segmentation methods and understanding the effect of spatial resolution on segmentation results is key to improve dryland vegetation monitoring. We explored and analyzed the accuracy of Object-Based Image Analysis (OBIA) and Mask Region-based Convolutional Neural Networks (Mask R-CNN) and the fusion of both methods in the segmentation of scattered vegetation in a dryland ecosystem. As a case study, we mapped Ziziphus lotus, the dominant shrub of a habitat of conservation priority in one of the driest areas of Europe. Our results show for the first time that the fusion of the results from OBIA and Mask R-CNN increases the accuracy of the segmentation of scattered shrubs up to 25% compared to both methods separately. Hence, by fusing OBIA and Mask R-CNNs on very high-resolution images, the improved segmentation accuracy of vegetation mapping would lead to more precise and sensitive monitoring of changes in biodiversity and ecosystem services in drylands.


Assuntos
Aprendizado Profundo , Ecossistema , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos
4.
Appl Environ Microbiol ; 86(12)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32276983

RESUMO

Mycoplasma haemocanis is prevalent in the endangered Darwin's fox (Lycalopex fulvipes) in its main stronghold, Chiloé Island (Chile). The origin of the infection, its dynamics, its presence in other fox populations and the potential consequences for fox health remain unexplored. For 8 years, hemoplasmal DNA was screened and characterized in blood from 82 foxes in Chiloé and two other fox populations and in 250 free-ranging dogs from Chiloé. The prevalence of M. haemocanis in foxes was constant during the study years, and coinfection with "Candidatus Mycoplasma haematoparvum" was confirmed in 30% of the foxes. Both hemoplasma species were detected in the two mainland fox populations and in Chiloé dogs. M. haemocanis was significantly more prevalent and more genetically diverse in foxes than in dogs. Two of the seven M. haemocanis haplotypes identified were shared between these species. Network analyses did not show genetic structure by species (foxes versus dogs), geographic (island versus mainland populations), or temporal (years of study) factors. The probability of infection with M. haemocanis increased with fox age but was not associated with sex, season, or degree of anthropization of individual fox habitats. Some foxes recaptured years apart were infected with the same haplotype in both events, and no hematological alterations were associated with hemoplasma infection, suggesting tolerance to the infection. Altogether, our results indicate that M. haemocanis is enzootic in the Darwin's fox and that intraspecific transmission is predominant. Nevertheless, such a prevalent pathogen in a threatened species represents a concern that must be considered in conservation actions.IMPORTANCEMycoplasma haemocanis is enzootic in Darwin's foxes. There is a higher M. haemocanis genetic diversity and prevalence in foxes than in sympatric dogs, although haplotypes are shared between the two carnivore species. There is an apparent tolerance of Darwin's foxes to Mycoplasma haemocanis.


Assuntos
Infecções Assintomáticas/epidemiologia , Coinfecção/veterinária , Doenças do Cão/epidemiologia , Raposas , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Animais , Chile/epidemiologia , Coinfecção/epidemiologia , Coinfecção/microbiologia , Doenças do Cão/microbiologia , Cães , Espécies em Perigo de Extinção , Feminino , Masculino , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Prevalência
5.
BMC Palliat Care ; 17(1): 81, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29807537

RESUMO

BACKGROUND: Breakthrough cancer pain (BTcP) is defined according to its principal characteristics: high intensity, short time interval between onset and peak intensity, short duration, potential recurrence over 24 h and non-responsiveness to standard analgesic regimes. The Edmonton Classification System for Cancer Pain (ECS-CP) is a classification tool that evaluates different dimensions of pain. The aim of this study was to measure prevalence and the main characteristics of BTcP in a sample of advanced cancer patients and to explore the complexity observed when ECS-CP is incorporated into BTcP diagnostics algorithm. METHODS: Descriptive prevalence study (Retrospective chart review). Davies' algorithm was used to identify BTcP and ECS-CP was used to recognize appropriate dimensions of pain. The study was conducted in a sample of advanced cancer patients attending hospital outpatient clinic in Lleida, Spain. 277 patients were included from 01/01/2014 to 31/12/2015. No direct contact was made with participants. The following information was extracted from the palliative care outpatient clinic database: age, gender, civil status, cognitive impairment status, functional performance status and variables related to tumour. Only BTcP cases were included. RESULTS: Prevalence of BTcP was 39.34% (63.9% men). Mean of age was 68.2 years. Main diagnosis was lung cancer (n = 154; 31.6%). Metastases were diagnosed in 83% of the sample. 138 patients (49.8%) were diagnosed with 1 type of BTcP and 139 (50.2%) were diagnosed with more than one type of BTcP. In total, 488 different types of BTcP were recorded (mean 1.75 ± 0, 9), 244 of these types (50%) presented a component of neuropathic pain. Addictive behaviour, measured through CAGE test, was present in 29.2% (N = 81) of the patients and psychological distress was present in 40.8% (n = 113). CONCLUSIONS: Prevalence of BTcP (39.34%) is similar to the one reflected in the existing literature. Study results indicate that the routine use of ECS-CP in a clinical setting allows us to detect more than one type of BTcP as well as additional complexity associated with pain (neuropathic, addictive behavior and psychological distress).


Assuntos
Dor Irruptiva/diagnóstico , Dor do Câncer/diagnóstico , Medição da Dor/métodos , Idoso , Algoritmos , Dor Irruptiva/epidemiologia , Dor do Câncer/epidemiologia , Feminino , Hospitais de Ensino , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Estudos Retrospectivos , Espanha/epidemiologia
6.
Gastroenterol Hepatol ; 38(9): 525-33, 2015 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-25911974

RESUMO

INTRODUCTION: There are few studies on iron deficiency anemia (IDA) after non-variceal acute upper gastrointestinal bleeding (UGIB) in patients without portal hypertension. OBJECTIVES: To define the incidence of IDA after UGIB, to characterize the predictive factors for IDA and to design algorithms that could help physicians identify those patients who could benefit from iron therapy. MATERIAL AND METHOD: We registered 391 patients with UGIB between April 2007 and May 2009. Patients with portal hypertension and those with clinical or/and biological conditions that could affect the ferrokinetic pattern were excluded. Blood analyses were performed, including ferric parameters upon admission, on the 5th day, and on the 30th day after the hemorrhage episode. We used a multiple logistic regression model and a classification and regression tree model. RESULTS: A total of 124 patients were included, of which 76 (61.3%) developed IDA 30 days after UGIB. The predictive variables were age >75 years (P=.037; OR 3.9; 95% CI: 1.3-11.6), initial urea level >80mg/dL (P=.027; OR 2.9; 95% CI: 1.1-7.6), initial ferritin level ≤65ng/dL (P=.002; OR 7.6; 95% CI: 2.9-18.5), initial hemoglobin level ≤100g/L (P=.003; OR 3.2; 95% CI: 1.3-8.0), hemoglobin level on the 5th day ≤100g/L (P<.001; OR 14.9; 95% CI: 3.6-61.1) and the value of the transferrin saturation index on the 5th day <10% (p<0.001; OR 7.2; 95% CI: 2.6-20.3). CONCLUSIONS: Most patients with UGIB developed IDA 30 days after the episode. Identification of the predictive factors for IDA may help to establish guidelines for the administration of iron therapy.


Assuntos
Anemia Ferropriva/etiologia , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Ferropriva/epidemiologia , Anti-Inflamatórios não Esteroides/efeitos adversos , Anticoagulantes/efeitos adversos , Árvores de Decisões , Progressão da Doença , Endoscopia Gastrointestinal , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Úlcera Péptica Hemorrágica/complicações , Estudos Prospectivos , Recidiva , Fatores de Risco , Transferrina/análise , Adulto Jovem
7.
Environ Microbiol ; 16(4): 1069-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24148079

RESUMO

Borrelia burgdorferi sensu lato (s.l.), transmitted by Ixodes spp. ticks, is the causative agent of Lyme disease. Although Ixodes spp. ticks are distributed in both Northern and Southern Hemispheres, evidence for the presence of B. burgdorferi s.l. in South America apart from Uruguay is lacking. We now report the presence of culturable spirochetes with flat-wave morphology and borrelial DNA in endemic Ixodes stilesi ticks collected in Chile from environmental vegetation and long-tailed rice rats (Oligoryzomys longicaudatus). Cultured spirochetes and borrelial DNA in ticks were characterized by multilocus sequence typing and by sequencing five other loci (16S and 23S ribosomal genes, 5S-23S intergenic spacer, flaB, ospC). Phylogenetic analysis placed this spirochete as a new genospecies within the Lyme borreliosis group. Its plasmid profile determined by polymerase chain reaction and pulsed-field gel electrophoresis differed from that of B. burgdorferi B31A3. We propose naming this new South American member of the Lyme borreliosis group B. chilensis VA1 in honor of its country of origin.


Assuntos
Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/isolamento & purificação , Animais , Sequência de Bases , Grupo Borrelia Burgdorferi/classificação , Chile , DNA Bacteriano/genética , Cervos/parasitologia , Feminino , Ixodes/microbiologia , Ixodes/fisiologia , Masculino , Dados de Sequência Molecular , Filogenia , Roedores/parasitologia
8.
Materials (Basel) ; 17(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612073

RESUMO

The construction sector must incorporate the circular economy to improve sustainability and efficiency. The use of recycled aggregates (RAs) as a substitute for natural aggregates (NAs) is currently being investigated and is expected to yield considerable benefits in the future. The objective of this research is to evaluate the environmental and economic benefits of using recycled coarse aggregates (RCAs) in different 1 m3 samples of concrete, substituting the natural coarse aggregate (NCAs) with RCAs in different percentages. RCAs generally come from the treatment of construction and demolition wastes (CDWs). However, in this research, the RCAs are the concrete block wastes (CBWs) generated by a concrete production plant. Among the most notable results is that compared to concrete with no RCAs, using alternatives in which RCAs have replaced 50% of the NCAs leads to an average decrease in impact category statistics of -3.30%. In contrast to the existing literature on the subject, the process of producing RCAs generated efficiency improvements in categories such as abiotic depletion of fossil fuels (-58.72%) and global warming potential (-85.13%). This is because the transport process, a key factor in determining the viability of using RAs instead of NAs, was eliminated. In economic terms, there is a slight decrease in the financial cost of producing 1 m3 of concrete as the quantity of RCAs increases. The maximum decrease was 0.23€/m3 in the samples studied. Combining both the environmental and economic aspects resulted in a reduction factor of 0.420 g of CO2/€cent, which means fewer CO2 emissions per unit cost when using RCAs. In conclusion, these results are intended to further knowledge in the field of using RAs instead of NAs in order to help the sector achieve sustainability and find an alternative use for a particular type of business waste.

9.
Laryngoscope Investig Otolaryngol ; 9(1): e1182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38362196

RESUMO

Objective: To analyze the impact, performance, degree of specialization, and collaboration patterns of the worldwide scientific production on tissue engineering in otorhinolaryngology at the level of countries and institutions. Methods: Two different techniques were used, performance and science mapping analyses, using as samples all the available documents regarding tissue engineering focused on otorhinolaryngology applications. The dataset was retrieved from the Core Collection of the Web of Science database from 1900 to 2020. Social structure was analyzed using science mapping analysis with VOSviewer software. Results: The United States was the main producer, followed by Germany, and Japan. Malaysia and Germany had the highest Relative Specialization Index, indicating their greater relative interest in this area compared to other countries. The social structure analysis showed that the United States and Germany had significant co-authorship relationships with other countries. The University of California System, Kyoto University, and Harvard University were the leading institutions producing literature in this field. These latter two institutions showed the largest number of collaborations, although most of them were with institutions within their own country. There was a lack of connections between different communities of research. Conclusion: The United States is the main country driving progress in this research area, housing the most notable institutions. However, significant collaborations between these research centers are currently lacking. Encouraging greater cooperation among these institutions and their researchers would promote the exchange of knowledge, ultimately facilitating and accelerating advancements in this field.

10.
Animals (Basel) ; 14(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396494

RESUMO

A significant gap in exposure data for most livestock and zoonotic pathogens is common for several Latin America deer species. This study examined the seroprevalence against 13 pathogens in 164 wild and captive southern pudu from Chile between 2011 and 2023. Livestock and zoonotic pathogen antibodies were detected in 22 of 109 wild pudus (20.18%; 95% CI: 13.34-29.18) and 17 of 55 captive pudus (30.91%; 95% CI: 19.52-44.96), including five Leptospira interrogans serovars (15.38% and 10.71%), Toxoplasma gondii (8.57% and 37.50%), Chlamydia abortus (3.03% and 12.82%), Neospora caninum (0.00% and 9.52%), and Pestivirus (8.00% and 6.67%). Risk factors were detected for Leptospira spp., showing that fawn pudu have statistically significantly higher risk of positivity than adults. In the case of T. gondii, pudu living in "free-range" have a lower risk of being positive for this parasite. In under-human-care pudu, a Pestivirus outbreak is the most strongly suspected as the cause of abortions in a zoo in the past. This study presents the first evidence of Chlamydia abortus in wildlife in South America and exposure to T. gondii, L. interrogans, and N. caninum in wild ungulate species in Chile. High seroprevalence of livestock pathogens such as Pestivirus and Leptospira Hardjo in wild animals suggests a livestock transmission in Chilean template forest.

11.
J Gen Virol ; 94(Pt 12): 2745-2749, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24045108

RESUMO

We report the detection and characterization of a novel gammaherpesvirus in the critically endangered Darwin's fox (Lycalopex fulvipes; syn. Pseudalopex fulvipes) on Chiloé Island, Chile. Out of 28 analysed blood samples stored in alcohol, four were positive for this herpesvirus using a previously described pan-herpesvirus PCR assay targeting the herpesvirus DNA polymerase. Positive samples were subsequently characterized by means of a PCR targeting a 500 bp fragment of the glycoprotein B of the gammaherpesviruses. This novel herpesvirus was most closely related to other gammaherpesviruses from terrestrial carnivores, and is tentatively named Darwin's fox gammaherpesvirus. No apparent lesions were observed in the surveyed foxes. This is the first report of a gammaherpesvirus infecting a canid worldwide, and also of one infecting a carnivore from South America.


Assuntos
Espécies em Perigo de Extinção , Raposas/virologia , Gammaherpesvirinae/classificação , Gammaherpesvirinae/genética , Infecções por Herpesviridae/veterinária , Animais , DNA Polimerase Dirigida por DNA/genética , Feminino , Infecções por Herpesviridae/virologia , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética
12.
Ecology ; 104(4): e4003, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36808380

RESUMO

Providing historical data on riparian plant biodiversity and physico-chemical parameters of stream water in Mediterranean mountains helps to assess the effects of climate change and other human stressors on these sensitive and critical ecosystems. This database collects data from the main natural headwater streams of the Sierra Nevada (southeastern Spain), a high mountain (up to 3479 m above sea level [m asl]) recognized as a biodiversity super hotspot in the Mediterranean basin. On this mountain, rivers and landscapes depend on snowmelt water, representing an excellent scenario for evaluating global change's impacts. This dataset covers first- to third-order headwater streams at 41 sites from 832 to 1997 m asl, collected from December 2006 to July 2007. Our goal is to supply information on the vegetation associated with streambanks, the essential physico-chemical parameters of stream water, and the physiographic features of the subwatersheds. Riparian vegetation data correspond to six plots sampled at each site, including total canopy, individual number, height and DBH (diameter at breast height) in woody species, and cover percentage for herbs. Physico-chemical parameters were measured in situ (electric conductivity, pH, dissolved O2 concentration, stream discharge) and determined in the laboratory (alkalinity, soluble reactive phosphate-phosphorus [SRP], total phosphorus [TP], nitrate-nitrogen [ NO 3 - -N], ammonium-nitrogen [ NH 4 + -N], total nitrogen [TN]). Watershed physiographic variables comprise drainage area, minimum altitude, maximum altitude, mean slope, orientation, stream order, stream length, and land cover surface percentage. We recorded 197 plant taxa (67 species, 28 subspecies, and 2 hybrids), representing 8.4% of the Sierra Nevada vascular flora. Due to the botanical nomenclature used, the database can be linked to FloraSNevada database, contributing to Sierra Nevada (Spain) as a laboratory of global processes. This data set can be freely used for non-commercial purposes. Users of these data should cite this data paper in any publications resulting from its use.


Assuntos
Ecossistema , Água , Humanos , Espanha , Nitrogênio/análise , Fósforo/análise
13.
Sci Total Environ ; 897: 166289, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37591403

RESUMO

Anthropogenic environmental change is reducing available habitat for wild species, providing novel selection pressures such as infectious diseases and causing species to interact in new ways. The potential for emerging infectious diseases and zoonoses at the interface between humans, domestic animals, and wild species is a key global concern. In vertebrates, diversity at the major histocompatibility complex MHC is critical to disease resilience, and its study in wild populations provides insights into eco-evolutionary dynamics that human activities alter. In natural populations, variation at MHC loci is partly maintained by balancing selection, driven by pathogenic selective pressures. We hypothesize that MHC genetic diversity differs between guigna populations inhabiting human-dominated landscapes (higher pathogen pressures) versus more natural habitats (lower pathogen pressures). We predict that MHC diversity in guignas would be highest in human-dominated landscapes compared with continuous forest habitats. We also expected to find higher MHC diversity in guignas infected with micro and macro parasites (higher parasite load) versus non infected guignas. We characterized for the first time the genetic diversity at three MHC class I and II exons in 128 wild guignas (Leopardus guigna) across their distribution range in Chile (32-46° S) and Argentina, representing landscapes with varying levels of human disturbance. We integrated MHC sequence diversity with multiple measures of anthropogenic disturbance and both micro and macro parasite infection data. We also assessed signatures of positive selection acting on MHC genes. We found significantly higher MHC class I diversity in guignas inhabiting landscapes where houses were present, and with lower percentage of vegetation cover, and also in animals with more severe cardiorespiratory helminth infection (richness and intensity) and micro-macroparasite co-infection. This comprehensive, landscape-level assessment further enhances our knowledge on the evolutionary dynamics and adaptive potential of vertebrates in the face of emerging infectious disease threats and increasing anthropogenic impacts.


Assuntos
Variação Genética , Parasitos , Animais , Gatos , Humanos , Efeitos Antropogênicos , Seleção Genética , Animais Domésticos
14.
Materials (Basel) ; 16(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687432

RESUMO

The use of fibres applied to concrete in order to improve its properties is widely known. Nowadays, research is not only focused on improving mechanical properties but also on the environmental implications. The aim of this research was a mechanical and environmental comparison between different types of fibres. For this purpose, commercial fibres of three materials were used: low carbon steel, modified polyolefins, and glass fibre. In order to improve the sustainability of the sector, we also analysed and compared the performance of using a waste product, such as fibres from machining operations on lathes. For the evaluation of the mechanical properties, compression and flexural tests were carried out. The results show that the use of low carbon steel fibres increases the flexural strength by 4.8%. At the environmental level, and in particular for impact categories such as the Global Warming Potential (GWP), lathe waste fibres prove to be the most suitable. For instance, compared to glass fibres, CO2 emissions are reduced by 14.39%. This is equivalent to a total of 38 kg CO2 emissions per m3 of reinforced concrete. In addition to avoiding the consumption of 482 MJ/m3 of fossil fuels, the results of the research indicate the feasibility of using waste fibres as a substitute for commercial fibres, contributing to an improved environmental balance without losing mechanical performance.

15.
Vet Q ; 43(1): 1-7, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36409461

RESUMO

Viral diseases jeopardize the health of wildlife in Chile. However, this country lacks health surveillance programs that allow for defining preventive measures to tackle such diseases. The objective of this study was to determine the occurrence and the genetic diversity of pestivirus, herpesvirus and adenovirus in pudus from Chile. Blood samples from wild (n=34) and captive (n=32) pudus were collected between 2011 and 2019 and analyzed through consensus PCR. All the samples were negative to pestivirus and adenovirus. Herpesvirus was confirmed in four captive, and one wild pudu. All four zoo animals share the same sequence for both polymerase and glycoprotein genes. Both sequences share a 100% identity with caprine herpesvirus-2, classifying them in the same cluster as the Macavirus group. In turn, novel sequences of the polymerase and glycoprotein B genes were obtained from the wild pudu. Our study reports the first evidence of CpHV-2 infection in Chile and South American ungulate populations. Further research will be necessary to assess the pathogenicity of CpHV-2 in this species. It is also urgently recommended that molecular, serological and pathological screening should be conducted in Chilean wild and captive pudus to understand the impact of the herpesvirus on their populations.


Assuntos
Cervos , Gammaherpesvirinae , Animais , Humanos , Chile/epidemiologia , Cabras , População da América do Sul
16.
Front Vet Sci ; 10: 1161093, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033637

RESUMO

Introduction: Recent evidence shows a high diversity of infectious agents in wildlife that represent a threat to human, domestic, and wild animal health. In Chile, wild populations of the most common cervid species, pudu (Pudu puda), have been reported as hosts for novel pathogens such as Mycoplasma ovis-like and a novel ecotype of Anaplasma phagocytophilum. A better understanding of the epidemiology of this group and other intracellular bacteria that might have cervids as hosts would enlighten their population relevance. This study aimed to determine the occurrence and genetic diversity of Bartonella spp., hemotropic mycoplasmas, and Coxiella burnetii in pudus from Chile. Methods: The DNA was extracted from the blood samples of 69 wild free-ranging and 30 captive pudus from Chile. A combination of real-time (nouG gene for Bartonella and IS1111 element for C. burnetii) and conventional PCR (16S rRNA for hemotropic Mycoplasma spp. and rpoB, gltA, and ITS for Bartonella spp.) was used for pathogen screening and molecular characterization. Results: DNA of Bartonella spp. was detected in 10.1% [95% CI (5.2-18.2%)] samples, hemotropic Mycoplasma spp. in 1.7% [95% CI (0.08-10.1%)], and C. burnetii in 1.0% [95% CI (0.05-6.3%)] samples. Two sequenced samples were identified as Mycoplasma ovis-like, and one free-ranging pudu was positive for C. burnetii. While one captive and two free-ranging pudus were positive for Bartonella henselae, one wild pudu was co-positive for B. henselae and Bartonella sp., similar to Bartonellae identified in ruminants. Discussion: To the best of our knowledge, this is the first report of B. henselae in wild ungulate species, and C. burnetii and Bartonella spp. in wild ungulate species in South America. Further research will be necessary to evaluate the potential role of pudu as reservoirs of infection and identify the sources for disease transmission among humans and wild and domestic animals.

17.
Sci Rep ; 13(1): 13492, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596295

RESUMO

Tissue engineering is a relatively recent research area aimed at developing artificial tissues that can restore, maintain, or even improve the anatomical and/or functional integrity of injured tissues. Otolaryngology, as a leading surgical specialty in head and neck surgery, is a candidate for the use of these advanced therapies and medicinal products developed. Nevertheless, a knowledge-based analysis of both areas together is still needed. The dataset was retrieved from the Web of Science database from 1900 to 2020. SciMAT software was used to perform the science mapping analysis and the data for the biomedical translation identification was obtained from the iCite platform. Regarding the analysis of the cognitive structure, we find consolidated research lines, such as the generation of cartilage for use as a graft in reconstructive surgery, reconstruction of microtia, or the closure of perforations of the tympanic membrane. This last research area occupies the most relevant clinical translation with the rest of the areas presenting a lower translational level. In conclusion, Tissue engineering is still in an early translational stage in otolaryngology, otology being the field where most advances have been achieved. Therefore, although otolaryngologists should play an active role in translational research in tissue engineering, greater multidisciplinary efforts are required to promote and encourage the translation of potential clinical applications of tissue engineering for routine clinical use.


Assuntos
Microtia Congênita , Otolaringologia , Humanos , Engenharia Tecidual , Ciência Translacional Biomédica , Cognição
18.
Front Vet Sci ; 10: 1321172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38362467

RESUMO

Introduction: Herpesvirus infections have been highlighted as emerging diseases affecting wildlife health and the conservation of several taxa. Malignant catarrhal fever (MCF) and infectious keratoconjunctivitis (IKC) are two viruses that infect wild ruminants. Nevertheless, epidemiological data on herpesviruses in South American wild ruminants are limited. An outbreak of caprine gammaherpesvirus-2 (CpHV-2) that recently was suspected as the cause of MCF in southern pudus (Pudu puda) prompted the need to conduct molecular screenings in Chilean cervids to understand the epidemiology of herpesviruses. The aim of this study was to determine the occurrence and genetic diversity of herpesviruses in free-ranging cervids from Chile. Methods: Herpesvirus infection was assessed in antemortem blood samples (n = 86) from pudus (n = 81) and huemuls (Hippocamelus bisulcus) (n = 5), as well as postmortem samples of spleen (n = 24) and lung (n = 3) from pudus, using a nested pan-herpesvirus PCR assay. Results: Combining all suitable sample types, DNA of pudu gammaherpesvirus-1 was detected in five pudues and five huemuls, with an overall prevalence of 9.90% (n = 10/101; 95% CI = 5.11-17.87%). One pudu tested positive for ovine gammaherpesvirus-2 (n = 1/96; 1.04%; 95% CI = 0.05-6.49%), and one pudu tested positive for a Macavirus sequence with 98.63 similarity to ovine gammaherpesvirus-2 (n = 96; 1.04%; 95% CI = 0.05-6.49%). Discussion: To the best of our knowledge, this is the first report of a herpesvirus in huemul and of ovine gammaherpesvirus-2 in Chile. Our results also confirm the active circulation of herpesvirus in free-ranging cervids in Chilean Patagonia, and as such, MCF should be considered as a possible cause of disease in free-ranging Chilean pudus and livestock species. Further research is necessary to develop a plan of systematic monitoring (serological and pathological screening) of herpesviruses in Chilean wild and domestic ruminants to understand their diversity and impact on animal health and conservation.

19.
J Clin Tuberc Other Mycobact Dis ; 31: 100361, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36969920

RESUMO

Introduction: Patients with pulmonary tuberculosis (PTB) disease and positive sputum cultures are the main source of infection. Culture conversion time is inconsistent and defining the length of respiratory isolation is challenging. The objective of this study is to develop a score to predict the length of isolation period. Methods: A retrospective study was carried out to evaluated risk factors associated with persistent positive sputum cultures after 4 weeks of treatment in 229 patients with PTB. A multivariable logistic regression model was used to determinate predictors for positive culture and a scoring system was created based on the coefficients of the final model. Results: Sputum culture was persistently positive in 40.6%. Fever at consultation (1.87, 95% CI:1.02-3.41), smoking (2.44, 95% CI:1.36-4.37), >2 affected lung lobes (1.95, 95% CI:1.08-3.54), and neutrophil-to-lymphocyte ratio > 3.5 (2.22, 95% CI:1.24-3.99), were significantly associated with delayed culture conversion. Therefore, we assembled a severity score that achieved an area under the curve of 0.71 (95% CI:0.64-0.78). Conclusions: In patients with smear positive PTB, a score with clinical, radiological and analytical parameters can be used as a supplemental tool to assist clinical decisions in isolation period.

20.
Vet Q ; 43(1): 1-10, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36594266

RESUMO

BACKGROUND: The COVID-19 pandemic, caused by SARS-CoV-2 infection, has become the most devastating zoonotic event in recent times, with negative impacts on both human and animal welfare as well as on the global economy. Although SARS-CoV-2 is considered a human virus, it likely emerged from animals, and it can infect both domestic and wild animals. This constitutes a risk for human and animal health including wildlife with evidence of SARS-CoV-2 horizontal transmission back and forth between humans and wild animals. AIM: Molecular surveillance in different wildlife rehabilitation centers and wildlife associated institutions in Chile, which are critical points of animal-human interaction and wildlife conservation, especially since the aim of wildlife rehabilitation centers is to reintroduce animals to their original habitat. MATERIALS AND METHODS: The survey was conducted in six WRCs and three wildlife associated institutions. A total of 185 samples were obtained from 83 individuals belonging to 15 different species, including vulnerable and endangered species. Each specimen was sampled with two different swabs: one oropharyngeal or nasopharyngeal according to the nostril diameter, and/or a second rectal sample. RNA was extracted from the samples and two different molecular assays were performed: first, a conventional RT-PCR with pan-coronavirus primers and a second SARS-CoV-2 qPCR targeting the N and S genes. RESULTS: All 185 samples were negative for SARS-CoV-2. CLINICAL RELEVANCE: This study constitutes the first report on the surveillance of SARS-CoV-2 from wildlife treated in rehabilitation centers in Chile, and supports the biosafety procedures adopted in those centers.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Animais , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/veterinária , Animais Selvagens , Pandemias , Teste para COVID-19/veterinária
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