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1.
Sci Total Environ ; 914: 169651, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38159766

RESUMEN

Central Chile is undergoing its most severe drought since 2010, affecting ecosystems, water supply, agriculture, and industrial uses. The government's short-term measures, such as increasing groundwater extraction (by 383 % from 1997 to 2022), are exacerbating the situation, leading to long-term hydrological deterioration. The objective of this research is to establish the main processes driving the water table depth evolution within Central Chile over the period 1979-2023. This is done by conducting groundwater balances on five major hydrological basins of Central Chile. For the Megadrought (MD) period (2010-2022), the groundwater level depths reflect not only the recharge variability but, especially, the forcing trend of groundwater withdrawals: they represent 35 % and 65 %, respectively, of the total phreatic level drawdown. This result underlines the dominant role played by groundwater withdrawals in the current delicate state of Central Chile's groundwater resources, while revealing that drought is a new complex phenomenon to deal with, in the midterm, to revert the current water resource trend in Central Chile. Our study moreover presents the impact of climate change in the basin in the framework of six different groundwater withdrawal scenarios. In the worst case (i.e., RCP8.5), the aquifer recharge decreases 18 % with respect to 1979-1997, which is the period assumed to be unaffected by the impact of MD and withdrawals. Such a reduction may be irrelevant in the dynamics of the aquifer system if the current extraction rate does not change. The estimated recovery time needed to reach aquifer conditions equal to those of the unaffected period is approximately 50 years.

2.
Microbiol Spectr ; 11(3): e0462022, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37074170

RESUMEN

We report a plasmid-encoded IMI-6 carbapenemase in a clinical isolate of Enterobacter ludwigii from Spain. The isolate belongs to ST641 and was susceptible to expanded-spectrum cephalosporins and resistant to carbapenems. The modified carbapenem inactivation method (mCIM) test was positive, but ß-Carba was negative. Whole-genome sequencing identified the blaIMI-6 gene located in a conjugative IncFIIY plasmid and associated with the LysR-like regulator imiR. Both genes were bracketed by an ISEclI-like insertion sequence and a putatively defective ISEc36 insertion sequence. IMPORTANCE IMI carbapenemases confer an unusual resistance pattern of susceptibility to broad-spectrum cephalosporins and piperacillin-tazobactam but decreased susceptibility to carbapenems, which may make them difficult to detect in routine practice. Commercially available molecular methods for the detection of carbapenemases in clinical laboratories do not usually include blaIMI genes, which could contribute to the hidden dissemination of bacteria producing these enzymes. Techniques should be implemented to detect minor carbapenemases that are not very frequent in our environment and control their dissemination.


Asunto(s)
Antibacterianos , Elementos Transponibles de ADN , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Proteínas Bacterianas/genética , Plásmidos/genética , Carbapenémicos/farmacología , Cefalosporinas , Pruebas de Sensibilidad Microbiana
3.
Theriogenology ; 202: 28-35, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36893660

RESUMEN

The cryotolerance of equine blastocysts larger than 300 µm can be improved by aspirating blastocoele fluid prior to vitrification; however, it is not known whether blastocoele aspiration also enables successful slow-freezing. The aim of this study was therefore to determine whether slow-freezing of expanded equine embryos following blastocoele collapse was more or less damaging than vitrification. Grade 1 blastocysts recovered on day 7 or 8 after ovulation were measured (>300-550 µm, n = 14 and > 550 µm, n = 19) and blastocoele fluid was aspirated prior to slow-freezing in 10% glycerol (n = 14), or vitrification (n = 13) in 16.5% ethylene glycol/16.5% DMSO/0.5 M sucrose. Immediately after thawing or warming, embryos were cultured for 24 h at 38 °C and then graded and measured to assess re-expansion. Control embryos (n = 6) were cultured for 24 h following aspiration of blastocoel fluid, without cryopreservation or exposure to cryoprotectants. Subsequently, embryos were stained to assess live/dead cell proportion (DAPI/TOPRO-3), cytoskeleton quality (Phalloidin) and capsule integrity (WGA). For 300-550 µm embryos, quality grade and re-expansion were impaired after slow-freezing but not affected by vitrification. Slow-freezing embryos >550 µm induced additional cell damage as indicated by a significant increase in dead cell proportion and disruption of the cytoskeleton; neither of these changes were observed in vitrified embryos. Capsule loss was not a significant consequence of either freezing method. In conclusion, slow-freezing of expanded equine blastocysts collapsed by blastocoel aspiration compromises post-thaw embryo quality more than vitrification.


Asunto(s)
Blastocisto , Desarrollo Embrionario , Femenino , Animales , Caballos , Congelación , Criopreservación/veterinaria , Criopreservación/métodos , Vitrificación
4.
Radiologia (Engl Ed) ; 64(5): 415-421, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36243441

RESUMEN

INTRODUCTION: The use of general anesthesia in infants involves both short-term and long-term risks. The aim of this study is to evaluate the efficacy of brain MRI without anesthesia in infants younger than 3-month-old immobilized with a pillow. PATIENTS AND METHODS: This prospective case-control study was done in 2019. Cases were stable patients less than 3 months old who did not require ventilatory support for whom brain MRI was indicated. Patients were fed so they would fall asleep and placed in the scanner with an immobilizing pillow. Controls were clinically unstable patients matched for age and sex referred for brain MRI under general anesthesia. Three pediatric radiologists evaluated the success of the MRI study (whether it answered the clinical question), recorded whether it was necessary to repeat the study, and rated the presence of motion artifacts on a scale ranging from 1 to 4. RESULTS: A total of 47 cases were included (28 boys and 19 girls; mean age, 31 days). Of these, 42 (89%) MRI studies were considered successful. The proportion of successful MRI studies was lower in outpatients than in inpatients (p = 0.02). The quality of MRI in cases was considered optimal in 60% and suboptimal (motion artifacts in one or two sequences) in 30%. No safety issues related with the technique were detected. The mean duration of the studies was 16.6 min (range, 6-30 min). All of the MRI studies in controls were considered successful; quality was considered optimal in 89% and suboptimal in 11%. In the first year in which we used this technique, we avoided the use of general anesthesia in 47 MRI studies in 42 newborns. CONCLUSION: Brain MRI using the feed and sleep technique in infants younger than 3-month-old immobilized with a pillow can be done safely and efficaciously without general anesthesia.


Asunto(s)
Artefactos , Imagen por Resonancia Magnética , Anestesia General , Encéfalo/diagnóstico por imagen , Estudios de Casos y Controles , Niño , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino
5.
Int J Hyg Environ Health ; 244: 114004, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35816847

RESUMEN

Chlorination has historically provided microbiologically safe drinking water in public water supplies. Likewise, chlorine has also been introduced as a low-cost disinfection method in rural and marginalized communities, both at community and household level, as well as during emergencies. Although this practice is common and well established for use as a household water treatment technology in the Global South, several challenges in effective and efficient implementation still need to be addressed. Here, we explored these issues by a literature review and narrowed them to the status of three Latin American countries (Mexico, Colombia, and Brazil). Overall, it was found that although guidance on household-based chlorination includes information on health risks and hygiene, this may not create enough incentive for the user to adapt the method satisfactorily. Physicochemical quality of the water influences chlorination efficiency and it is found that variations in quality are rarely considered when recommending chlorine doses during implementation. These are far more often based on a few measurements of turbidity, thereby not considering dissolved organic matter, or seasonal and day-to-day variations. Other factors such as user preferences, chlorine product quality and availability also represent potential barriers to the sustainable use of chlorination. For chlorination to become a sustainable household water treatment, more focus should therefore be given to local conditions prior to the intervention, as well as support and maintenance of behavioural changes during and after the intervention.


Asunto(s)
Desinfección , Purificación del Agua , Cloro , Halogenación , América Latina , Abastecimiento de Agua
6.
Rev. chil. enferm. respir ; 38(2): 96-105, jun. 2022. tab, ilus
Artículo en Español | LILACS | ID: biblio-1407775

RESUMEN

Resumen En la práctica clínica, la radiografía de tórax permite confirmar el diagnóstico y la extensión de la neumonía adquirida en la comunidad (NAC). Objetivos: Examinar las características radiográficas de la NAC según el agente causal y el grado de concordancia interobservador (CI) en la descripción de los hallazgos radiográficos. Métodos: Se evaluaron las radiografías de tórax de 300 pacientes adultos inmunocompetentes hospitalizados por NAC, tres residentes de radiología consignaron el patrón de los infiltrados pulmonares, su localización anatómica y extensión, la presencia de derrame pleural y otros hallazgos radiográficos. Se realizaron cultivos de esputo, hemocultivos, pruebas serológicas y técnicas de biología molecular de hisopado nasofaríngeo para identificar los principales patógenos respiratorios. Resultados: Las manifestaciones clínicas y los hallazgos de la radiografía de tórax fueron similares en las neumonías causadas por diferentes patógenos respiratorios: bacterias clásicas, virus respiratorios y microorganismos atípicos. En las neumonías bacterianas predominó el patrón de relleno alveolar de distribución lobar, en las neumonías vírales y atípicas predominó el patrón intersticial o mixto alvéolo-intersticial con opacidades en vidrio esmerilado. La CI fue satisfactoria (kappa > 0,6) para determinar el patrón principal de los infiltrados pulmonares, su localización anatómica y la presencia de derrame pleural, su localización y extensión. La CI fue moderada (kappa 0,4-0,6) para definir la extensión de la neumonía y detectar signos radiológicos asociados a congestión pulmonar. Conclusión: Los hallazgos de la radiografía de tórax no permitieron identificar con precisión el agente causal de la neumonía, siendo útil en la caracterización de los infiltrados pulmonares y para detectar complicaciones como el derrame paraneumónico.


In a clinical setting the chest radiograph is the reference standard in establishing the diagnosis of community-acquired pneumonia (CAP). Objectives: This study aimed to assess interobserver reliability (IR) of radiographic findings and the relationship to different respiratory pathogens in CAP. Methods: Chest radiographs of 300 immunocompetent adult patients hospitalized with pneumonia, obtained from a database, were reviewed by three residents of radiology without specific clinical information. Main pattern of pulmonary infiltrates, topographic localization, extent of pneumonia, presence of pleural fluid, thickened bronchial walls, lymphadenopathy and air bronchogram were scored. Sputum and blood cultures, serological tests and nasopharyngeal swab for respiratory virus detection by molecular diagnostic techniques were performed to identify the causative pathogen. Results: Clinical manifestations and chest X-ray findings were similar in pneumonias caused by different respiratory pathogens: classic bacteria, respiratory viruses and atypical microorganisms. The alveolar pattern of lobar distribution predominated in bacterial pneumonia; meanwhile, interstitial or mixed alveolar-interstitial pattern with ground glass opacities predominated in viral and atypical pneumonias. IR was fair to good (kappa > 0.6) for determining the main pattern of infiltrates, anatomical location and the presence of pleural effusion, their anatomical location and extension. IR was moderate (kappa 0.4-0.6) for determining the extent of pneumonia and signs of congestive heart failure. Conclusion: Simple features such as main pattern description, anatomical location, identifying the involved lobes and pleural fluid recognition showed fair to excellent interobserver reliability. Chest radiographs was of limited value in predicting the causative pathogen but were of beneficial use to characterize pulmonary infiltrates and to detect complications such as parapneumonic effusion.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Infecciones Comunitarias Adquiridas/etiología , Infecciones Comunitarias Adquiridas/diagnóstico por imagen , Bacterias/aislamiento & purificación , Virus/aislamiento & purificación , Radiografía Torácica , Variaciones Dependientes del Observador , Estudios Prospectivos , Reproducibilidad de los Resultados , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/virología , Inmunocompetencia
7.
BMJ Open ; 12(5): e056193, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35551079

RESUMEN

INTRODUCTION: Successful emotion regulation (ER) is critical for psychological health. Disturbances in this ability are associated with several psychiatric disorders. There are several self-report questionnaires to assess ER. However, there are no studies synthesising the evidence on their psychometric properties. We aim to identify all available instruments addressing ER in adolescents or adults and to critically appraise, compare and summarise the quality of their psychometric properties. For this, we will use COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria. METHOD AND ANALYSIS: The search process to identify eligible studies will be conducted in April 2021 including the ProQuest, PubMed, Scopus and Web of Science databases with no restriction in terms of publication date. Eligibility criteria include peer-reviewed research articles written in English or Spanish by means of patient-reported outcome measures focused on ER among participants of 13 years or older. We will assess the quality of measures according to the COSMIN Risk of Bias Checklist. The psychometric properties will be assessed by the COSMIN updated criteria for good measurement. The available evidence will be addressed by the Grading of Recommendations, Assessment, Development and Evaluations approach. Our findings will be synthesised independently for each measure, including information on their sample, theoretical model and psychometric properties when possible. ETHICS AND DISSEMINATION: Ethical approval is not required, as this study does not involve any participants or collection of primary data. Results are expected to be published in a peer-reviewed journal in the field of youth mental health and presented at relevant meetings and conferences. PROSPERO REGISTRATION NUMBER: CRD42021249498.


Asunto(s)
Regulación Emocional , Adolescente , Adulto , Humanos , Medición de Resultados Informados por el Paciente , Psicometría , Autoinforme , Encuestas y Cuestionarios
8.
Sci Total Environ ; 825: 153937, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35189216

RESUMEN

The acequias de careo are ancestral water channels excavated during the early Al-Andalus period (8th-10th centuries), which are used to recharge aquifers in the watersheds of the Sierra Nevada mountain range (Southeastern Spain). The water channels are maintained by local communities, and their main function is collecting snowmelt, but also runoff from rainfall from the headwaters of river basins and distributing it throughout the upper parts of the slopes. This method of aquifer artificial recharge extends the availability of water resources in the lowlands of the river basins during the dry season when there is almost no precipitation and water demand is higher. This study investigates the contribution of the careo channels in the watershed of Bérchules concerning the total aquifer recharge during the 2014-2015 hydrological year. Several channels were gauged, and the runoff data were compared with those obtained from a semi-distributed hydrological model applied to the same hydrological basin. The natural infiltration of meteoric waters accounted for 52% of the total recharge, while the remaining 48% corresponded to water transported and infiltrated by the careo channels. In other words, the careo recharge system enhances by 92% the natural recharge to the aquifer. Our results demonstrate the importance of this ancestral and efficient channel system for recharging slope aquifers developed in hard rocks. The acequias de careo are nature-based solutions for increasing water resources availability that have contributed to a prosperous life in the Sierra Nevada. Its long history (>1200 years) suggests that the system has remarkable resilience properties, which have allowed adaptation and permance for centuries in drastically changing climatic and socioeconomic conditions. This recharge system could also be applied to -or inspire similar adaptation measures in- semi-arid mountain areas around the world where it may help in mitigating climate change effects.


Asunto(s)
Agua Subterránea , Hidrología , Ríos , España , Agua
9.
Radiologia (Engl Ed) ; 63(5): 406-414, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34625196

RESUMEN

INTRODUCTION: The first-choice treatment for ileocolic intussusception is imaging-guided reduction with water, air, or barium. The objectives of the current study were to evaluate the efficacy and safety of ultrasound-guided reduction of intussusception using water in patients under sedation and analgesia. We compare this approach with our previous experience in reduction using barium under fluoroscopic guidance without sedation and analgesia and investigate what factors predispose to surgical correction. MATERIAL AND METHODS: We retrospectively reviewed cases of children with ileocolic intussusception treated in a third-level pediatric hospital during a 52-month period: during the first 24 months, reduction was done using barium and fluoroscopy without sedoanalgesia, and during the following 28 months, reduction was done using water and ultrasound with sedoanalgesia. A pediatric radiologist and a pediatrician reviewed the clinical history, surgical records, and imaging studies. RESULTS: In the 52-month period, 59 children (41 boys and 18 girls; mean age, 16.0 months) were diagnosed with ileocolic intussusception at our hospital. A total of 33 reductions (28 patients and 5 recurrences) were done using barium under fluoroscopic guidance, achieving a 61% success rate. A total of 38 reductions (31 patients and 7 recurrences) were done using water under ultrasound guidance with patients sedated, achieving a success rate of 76%. No significant adverse effects were observed in patients undergoing ultrasound-guided hydrostatic reduction under sedation, and the success rate in this group was higher (p = 0.20). The factors that predisposed to surgical reduction were greater length of the intussusception (p = 0.03), location in areas other than the right colon (p = 0.002), and a greater length of time between symptom onset and imaging tests (p = 0.08). CONCLUSION: Ultrasound-guided hydrostatic reduction of ileocolic intussusception under sedoanalgesia is efficacious and safe.


Asunto(s)
Analgesia , Intususcepción , Niño , Enema , Femenino , Humanos , Lactante , Intususcepción/diagnóstico por imagen , Masculino , Estudios Retrospectivos , Ultrasonografía Intervencional
10.
ESMO Open ; 6(3): 100159, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34023541

RESUMEN

Avapritinib is a protein kinase inhibitor designed to selectively inhibit oncogenic KIT and platelet-derived growth factor receptor alpha (PDGFRA) mutants by targeting the active conformation of the kinase. On 24 September 2020, a marketing authorisation valid through the European Union was issued for avapritinib as treatment of adult patients with unresectable or metastatic gastrointestinal stromal tumours (GIST) harbouring the PDGFRA D842V mutation. The drug was evaluated in an open-label, phase I, first-in-human, dose-escalation, open-label study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of avapritinib in adults with unresectable or metastatic GIST. The benefit of avapritinib was observed in patients with GIST harbouring the PDGFRA D842V mutation. The overall response rate was 95% (95% confidence interval 82.3%-99.4%), with a median duration of response of 22.1 months (95% confidence interval 14.1-not estimable months). The most common adverse events were nausea, fatigue, anaemia, periorbital and face oedema, hyperbilirubinaemia, diarrhoea, vomiting, increased lacrimation, and decreased appetite. Most of the reported cognitive effects were mild memory impairment. Rarer events were cases of severe encephalopathy and intracranial or gastrointestinal bleeding. The aim of this manuscript is to summarise the scientific review of the application leading to regulatory approval in the European Union.


Asunto(s)
Tumores del Estroma Gastrointestinal , Adulto , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Humanos , Mutación , Pirazoles , Pirroles , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Triazinas
11.
Trauma Case Rep ; 31: 100380, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33385056

RESUMEN

Percutaneous iliosacral screw placement has become the technique of choice for treating injuries to the posterior pelvis. However, the technique requires an understanding of the anatomy surrounding the bone corridors to avoid complications and detect them early if they occur. We present the clinical case of a patient with a U-shaped fracture of the sacrum that evolves with gluteal pain and left foot equine paresis after percutaneous fixation with iliosacral screws. Angio-CT of the pelvis shows active arterial bleeding from the superior gluteal artery associated to extensive hematoma in the thickness of the gluteus medius muscle. Emergency embolization is performed by installing coil and gelatin. Successful control of bleeding is achieved. To avoid this complication, a complete imaging study is recommended in planning the surgery and to avoid multiple repositioning of the guide or screw. Arterial injury should be suspected in case of increasing pain despite analgesia, functional impairment or neurological deficit and the angiographic study and resolution by selective embolization of the bleeding vessels must be performed.

13.
Radiologia (Engl Ed) ; 2020 Oct 14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33069365

RESUMEN

INTRODUCTION: The use of general anesthesia in infants involves both short-term and long-term risks. The aim of this study is to evaluate the efficacy of brain MRI without anesthesia in infants younger than 3-month-old immobilized with a pillow. PATIENTS AND METHODS: This prospective case-control study was done in 2019. Cases were stable patients less than 3 months old who did not require ventilatory support for whom brain MRI was indicated. Patients were fed so they would fall asleep and placed in the scanner with an immobilizing pillow. Controls were clinically unstable patients matched for age and sex referred for brain MRI under general anesthesia. Three pediatric radiologists evaluated the success of the MRI study (whether it answered the clinical question), recorded whether it was necessary to repeat the study, and rated the presence of motion artifacts on a scale ranging from 1 to 4. RESULTS: A total of 47 cases were included (28 boys and 19 girls; mean age, 31 days). Of these, 42 (89%) MRI studies were considered successful. The proportion of successful MRI studies was lower in outpatients than in inpatients (p=0.02). The quality of MRI in cases was considered optimal in 60% and suboptimal (motion artifacts in one or two sequences) in 30%. No safety issues related with the technique were detected. The mean duration of the studies was 16.6minutes (range, 6-30minutes). All of the MRI studies in controls were considered successful; quality was considered optimal in 89% and suboptimal in 11%. In the first year in which we used this technique, we avoided the use of general anesthesia in 47 MRI studies in 42 newborns. CONCLUSION: Brain MRI using the feed and sleep technique in infants younger than 3-month-old immobilized with a pillow can be done safely and efficaciously without general anesthesia.

14.
Trials ; 21(1): 900, 2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33121503

RESUMEN

BACKGROUND: HIV remains a major public health issue, especially in Eastern and Southern Africa. Pre-exposure prophylaxis is highly effective when adhered to, but its effectiveness is limited by cost, user acceptability and uptake. The cost of a non-inferiority phase III trial is likely to be prohibitive, and thus, it is essential to select the best possible drug, dose and schedule in advance. The aim of this study, the Combined HIV Adolescent PrEP and Prevention Study (CHAPS), is to investigate the drug, dose and schedule of pre-exposure prophylaxis (PrEP) required for the protection against HIV and the acceptability of PrEP amongst young people in sub-Saharan Africa, and hence to inform the choice of intervention for future phase III PrEP studies and to improve strategies for PrEP implementation. METHODS: We propose a mixed-methods study amongst young people aged 13-24 years. The first component consists of qualitative research to identify the barriers and motivators towards the uptake of PrEP amongst young people in South Africa, Uganda and Zimbabwe. The second component is a randomised clinical trial (ClinicalTrials.gov NCT03986970, June 2019) using a novel ex vivo HIV challenge method to investigate the optimal PrEP treatment (FTC-TDF vs FTC-TAF), dose and schedule. We will recruit 144 amongst HIV-negative uncircumcised men aged 13-24 years from voluntary male medical circumcision clinics in two sites (South Africa and Uganda) and randomise them into one of nine arms. One group will receive no PrEP prior to surgery; the other arms will receive either FTC-TDF or FTC-TAF, over 1 or 2 days, and with the final dose given either 6 or 20 h prior to surgery. We will conduct an ex vivo HIV challenge on their resected foreskin tissue. DISCUSSION: This study will provide both qualitative and quantitative results to help decide the optimum drug, dose and schedule for a future phase III trial of PrEP. The study will also provide crucial information on successful strategies for providing PrEP to young people in sub-Saharan Africa. TRIAL REGISTRATION: ClinicalTrials.gov NCT03986970 . Registered on 14 June 2019.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Adolescente , Fármacos Anti-VIH/efectos adversos , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Sudáfrica , Uganda , Zimbabwe
15.
Sci Total Environ ; 748: 141363, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32823224

RESUMEN

Time series of environmental tracers (groundwater stable isotope composition, electrical conductivity and temperature) and concentration breakthrough curves of artificial tracers (uranine, eosine, amino-G and naphtionate) have been analyzed to characterize fast preferential and slow matrix in-transit recharge flows in the Paleocene-Eocene limestone aquifer of the Ordesa and Monte Perdido National Park, an alpine karst system drained by a water table cave, a rare hydrological feature in high mountain karst systems with similar characteristics. Snowmelt favors the areal recharge of the system. This process is reflected in the large proportion of groundwater flowing through the connected porosity structure of the karst aquifer, which amounts the 75% of the total system water discharge. From the perspective of water resources recovery, the water capacity of the fissured-porous zone (matrix) represents 99% of the total karst system storage. The volume associated to the karst conduits is very small. The estimated mean travel times are 9 days for conduits and 475 days for connected porosity. These short travel times reveal high vulnerability of the karst system to pollutants in broad sense and a great impact of climate change on the associated water resources.

16.
Sci Total Environ ; 728: 138848, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32570324

RESUMEN

Most of the athalassic saline and hypersaline lakes are located in arid and semiarid regions where water availability drives the hydrological dynamics of the lake itself and the associated ecosystems. This is the case of the Salada de Chiprana Lake, in the Ebro River basin (Spain). It is the only athalassic permanent hypersaline lake in Western Europe, and where rare and endangered bacterial mats exist. This work presents a robust hydrogeological conceptual model for the lake system. The model evaluates the contribution of groundwater discharge to the whole water budget and explains the hydrological behaviour of the lake system. The lake behaves as a flow-through system rather than a closed basin. About 40% of total water outflow from the lake occurs as groundwater, whereas evaporation accounts for the remaining 60%. The surface water inflows are variable, but the groundwater contribution seems almost constant, amounting to 13% of the average total water inflow and contributing 1.9% of salt income. The high water salinity of the lake is controlled by evaporation, by saline water inflows from irrigation return flows, and the by groundwater outflows. The role of groundwater should be taken into account when drafting the water and land planning, once the conditions for the conservation of the algal mats are defined. A major contribution of this study is the water balance in the Salada de Chiprana Lake, which is consistent with a robust hydrogeological conceptual model defined upon scarce hydrogeological, hydrochemical and isotopic data in the local context as conditioned by the regional behaviour. The water balance is a key tool to help to correctly manage this unique athalassic saline lake, and the approach used here can be extrapolated to other similar ecosystems around the world.

17.
Theriogenology ; 154: 11-16, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32470704

RESUMEN

Embryo cryopreservation ensures that genetic biodiversity is preserved over time. This study evaluates the survival of donkey embryos subjected to slow freezing and vitrification after thawing and in vitro culture. Seven-day-old in vivo produced donkey embryos were subjected to slow freezing (SF, N = 14) or vitrification (VIT, N = 22). After one year of cryopreservation, embryos were warmed, washed and placed in incubation for in vitro culture (IVC). In order to assess the embryo viability, the quality grade and developmental stage were recorded after thawing and after 24 and 48 h of IVC. Eleven embryos (SF = 4 and VIT = 7) were incubated under a time-lapse camera, for up to 68 h, in order to determine the area and growth. The survival rate was not influenced by the procedure but by the developmental stage: after 48 h of IVC blastocyst survival rate (1/8, 12.5%) was significantly lower compared to both morulas (8/12, 66.7%) and early blastocysts (11/16, 68.7%) (P < 0.05). Embryo diameter class at recovery did not significantly influence the survival rate. In terms of the embryos that were judged to be alive after 48 h of IVC, quality grade 1 was observed in 7/8 (88%) and 4/12 (33%) of the SF and VIT embryos, respectively (P < 0.05). After time-lapse analysis, the IVC embryo area as well as growth percentage were statistically higher in the SF than the VIT embryos (P < 0.05). In conclusion, no difference in survival rates was found between the two cryopreservation procedures, although embryo quality was more negatively affected by vitrification.


Asunto(s)
Equidae , Vitrificación , Animales , Blastocisto , Criopreservación/veterinaria , Congelación , Tasa de Supervivencia
18.
Sci Rep ; 10(1): 1056, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31974438

RESUMEN

The major histocompatibility complex (MHC) influences sexual selection in various vertebrates. Recently, MHC-linked social signaling was also shown to influence female fertility in horses (Equus caballus) diagnosed 17 days after fertilization. However, it remained unclear at which stage the pregnancy was terminated. Here we test if MHC-linked cryptic female choice in horses happens during the first days of pregnancy, i.e., until shortly after embryonic entrance into the uterus and before fixation in the endometrium. We exposed estrous mares to one of several unrelated stallions, instrumentally inseminated them with semen of another stallion, and flushed the uterus 8 days later to test for the presence of embryos. In total 68 embryos could be collected from 97 experimental trials. This success rate of 70.1% was significantly different from the mean pregnancy rate of 45.7% observed 17 days after fertilization using the same experimental protocol but without embryo flushing. Embryo recovery rate was not significantly dependent on whether the mares had been socially exposed to an MHC-dissimilar or an MHC-similar stallion. These observations suggest that MHC-linked maternal strategies affect embryo survival mainly (or only) during the time of fixation in the uterus.


Asunto(s)
Caballos/genética , Complejo Mayor de Histocompatibilidad , Herencia Materna , Oviductos/inmunología , Animales , Embrión de Mamíferos/inmunología , Femenino , Caballos/embriología , Caballos/inmunología , Masculino , Embarazo
19.
BMC Genomics ; 20(1): 1016, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31878883

RESUMEN

BACKGROUND: White root rot disease caused by Rosellinia necatrix is one of the most important threats affecting avocado productivity in tropical and subtropical climates. Control of this disease is complex and nowadays, lies in the use of physical and chemical methods, although none have proven to be fully effective. Detailed understanding of the molecular mechanisms underlying white root rot disease has the potential of aiding future developments in disease resistance and management. In this regard, this study used RNA-Seq technology to compare the transcriptomic profiles of R. necatrix during infection of susceptible avocado 'Dusa' roots with that obtained from the fungus cultured in rich medium. RESULTS: The transcriptomes from three biological replicates of R. necatrix colonizing avocado roots (RGA) and R. necatrix growing on potato dextrose agar media (RGPDA) were analyzed using Illumina sequencing. A total of 12,104 transcripts were obtained, among which 1937 were differentially expressed genes (DEG), 137 exclusively expressed in RGA and 160 in RGPDA. During the root infection process, genes involved in the production of fungal toxins, detoxification and transport of toxic compounds, hormone biosynthesis, gene silencing and plant cell wall degradation were overexpressed. Interestingly, 24 out of the 137 contigs expressed only during R. necatrix growth on avocado roots, were predicted as candidate effector proteins (CEP) with a probability above 60%. The PHI (Pathogen Host Interaction) database revealed that three of the R. necatrix CEP showed homology with previously annotated effectors, already proven experimentally via pathogen-host interaction. CONCLUSIONS: The analysis of the full-length transcriptome of R. necatrix during the infection process is suggesting that the success of this fungus to infect roots of diverse crops might be attributed to the production of different compounds which, singly or in combination, interfere with defense or signaling mechanisms shared among distinct plant families. The transcriptome analysis of R. necatrix during the infection process provides useful information and facilitates further research to a more in -depth understanding of the biology and virulence of this emergent pathogen. In turn, this will make possible to evolve novel strategies for white root rot management in avocado.


Asunto(s)
Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad/genética , Persea/microbiología , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , Xylariales/genética , Xylariales/fisiología , Anotación de Secuencia Molecular , RNA-Seq
20.
Metro cienc ; 27(2): 72-77, dic. 2019. ilus
Artículo en Español | LILACS | ID: biblio-1104222

RESUMEN

La prevalencia de la diabetes mellitus tipo 2 está incrementando rápidamente a nivel mundial de manera paralela a la epidemia de obesidad. El número de personas con diabetes, alrededor del mundo, se ha duplicado en los últimos 20 años; una de las características más preocupantes de este rápido crecimiento es el aparecimiento de diabetes tipo 2 en niños, adolescentes y adultos jóvenes. Debido a la reducción de la esperanza de vida causada por las morbilidades producidas por la diabetes, los pacientes que sufren de esta patología requieren un manejo integral. La cirugía bariátrica / metabólica ha demostrado que: • Mejora significativamente el control glucémico. • Reduce los factores de riesgo cardiovasculares. • Incluso ha demostrado la posibilidad de producir remisión de la diabetes tipo 2, hipertensión arterial y otras comorbilidades asociadas con la obesidad. Los resultados de múltiples estudios demuestran claramente la eficacia de la cirugía metabólica en el control glucémico y de otras comorbilidades asociadas con la diabetes tipo 2 y la obesidad; se observa, con mucha frecuencia, casos de remisión de la diabetes, incluso hasta 5 años después de la intervención quirúrgica. Por esta razón, la Asociación Americana para la Diabetes (ADA) considera a la cirugía bariátrica como una opción terapéutica viable en pacientes obesos con diabetes mellitus tipo 2.Las cirugías gastrointestinales diseñadas para controlar la obesidad pueden mejorar la homeostasis de la glucosa más efectivamente que el tratamiento farmacológico-clínico y producir cambios importantes en el estilo de vida; incluso, en un considerable número de pacientes, se logra la remisión de la diabetes tipo 2. (AU)


The prevalence of type 2 diabetes mellitus is rapidly increasing to global level parallel to the epidemic that obesity. The number of people with diabetes, around the world, have doubled in the last 20 years; one of the most worrisome features of this rapid growth It is the appearance of type 2 diabetes in children, adolescents and young adults. Due to the reduction in life expectancy caused by morbidities produced by diabetes, patients suffering from this pathology require comprehensive management bariatric / metabolic surgery has shown that: • Significantly improves glycemic control. • Reduces cardiovascular risk factors. • It has even demonstrated the possibility of producing diabetes remission type 2, arterial hypertension and other comorbidities associated with obesity. The results of multiple studies clearly demonstrate the effectiveness of the metabolic surgery in glycemic control and other associated comorbidities with type 2 diabetes and obesity; cases are very often observed of remission of diabetes, even up to 5 years after the intervention surgical For this reason, the American Diabetes Association (ADA) considers bariatric surgery as a viable therapeutic option in obese patients with type 2 diabetes mellitus. Gastrointestinal surgeries designed to control obesity can improve glucose homeostasis more effectively than treatment clinical pharmacological and produce important changes in lifestyle; even, in a considerable number of patients, remission of the type 2 diabetes. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Enfermedades Nutricionales y Metabólicas , Cirugía Bariátrica , Obesidad
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