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Background: This study aims to assess the atherogenic index of plasma (AIP) diagnostic value in detecting diabetic foot osteomyelitis (DFO) among patients with diabetic foot ulcers (DFUs). Methods: A prospective cohort study was conducted on 80 patients with DFUs and suspected DFO between January 2022 and December 2023. The primary outcome measures included the diagnosis of DFO, determined by positive microbiological analysis results from bone samples and its correlation with the AIP. Receiver operating characteristic (ROC) curves were utilized to select the optimal diagnostic cut-off points for AIP and post hoc analysis was performed to evaluate the difference in the AIP for diagnosing DFO in patients with and without peripheral arterial disease (PAD). Results: The diagnostic potential for DFO in PAD patients of AIP-1 (Log TC/HDL) showed an AUC of 0.914 (p < 0.001 [0.832-0.996]), leading to a sensitivity of 83% and a specificity of 85%. By contrast, AIP-2 (Log TG/HDL) demonstrated a slightly lower AUC of 0.841 (p < 0.001 [0.716-0.967]), leading to a sensitivity of 76% and a specificity of 74%. Conclusions: The AIP tool, with its ideal blend of sensitivity and specificity, aids in predicting DFO effectively. Therefore, clinicians should consider using AIP for patients suffering from PAD and associated DFO.
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Background: Cacao (Theobromacacao L) is one of the most relevant crops in terms of economy and social rural development in Colombia. Cacao is also an important crop due to its potential to replace illicit crops and it is related to less deforestation and preserves the biodiversity. There are several cacao districts in Colombia, one of these being Arauca. The Department of Arauca is the second largest cocoa producing region in Colombia; however, it is heavily affected by armed conflict. To raise the knowledge and technology available in the region, integrating data on the occurrence of cacao farms with climatic variables becomes a powerful socioeconomic mapping tool for maintaining agrobiodiversity and food security in the region. Consequently, this type of agrodiversity data and agroclimatic approaches help to better manage agrobiodiversity, as in the cacao region of Arauca. These tools are even more relevant in biodiverse regions, such as flooded savannahs and tropical forest ecosystems, which are currently undergoing drastic changes due to agricultural expansion and climate change. One of the knowledge gaps in Colombia´s cacao regions is that there are currently no agroclimatic maps made with a social and scientific approach. This study aimed to provide a database of the spatial distribution of cacao farms in Arauca, as well as agroclimatic maps that identify and locate cacao climate regions in Arauca. We also present a presence-only matrix consisting of twenty-six tree species, or agrobiodiversity, distributed across the study region and specifically associated with the cacao forestry systems in Arauca. New information: We present the first database of both climate and agrobiodiversity data related to cacao farms in Arauca, developed with a research and socioeconomic vision that generated a novel approach for the agroclimatic zoning of cocoa in the Arauca Region and Colombia. Using 1,538 cacao farms at the regional scale, we identified two national and six regional-scale climate and soil regions. The selection at the local scale allowed us to classify 180 cacao farms comprising nine agroclimatic clusters in Arauca. We found twenty-six tree species distributed across the cacao climate zones. This dataset and its related maps also represent the agrobiodiversity of cultivated cacao locally. This is the most complete climate and agrobiodiversity dataset of cacao farms distribution in one of the top cocoa-producing regions in the country. These outputs are crucial because they constitute a baseline for developing research in the biodiversity of agroforestry systems, pests and diseases, pollutant presence, genetics, post-harvest processing and cocoa quality and safety.
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The current study aimed to evaluate the dispersal of solution and microbes (aerosol) in the clinical environment during treatment with Low-frequency contact ultrasonic debridement (LFCUD) with or without suction attachment in patients with diabetic foot ulcers (DFUs). We performed 20 treatments in 10 patients divided into two groups to receive the proposed LFCUD modalities. We measured the microbial load of the environment pre-treatment (sample M1), during treatment with each LFCUD modality (sample M2) and post-treatment (sample M3). The use of LFCUD debridement without a suction attachment results in significantly higher immediate contamination of the clinic environment than the suction attachment, particularly during the procedure (1.70 ± 0.98 log 10 CFU/mL versus 0.77 ± 0.85 log 10 CFU/mL, p = 0.035). When suction is not applied, there are statistically significant differences depending on whether the DFUs are neuropathic or neuroischemic, finding a greater number of microorganisms with high loads in neuropathic DFUs. We found a statistically significant positive correlation between wound area (r = 0.450, p = 0.047) and TBI (r = 0.651, p = 0.006) with the bacterial load during the LFCUD. Based on our results, we recommend using the personal protective equipment required to protect staff members and patients during treatment with LFCUD and using a suction attachment where clinically possible to reduce clinic environmental pollution, especially in neuropathic DFUs and those with larger areas.
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Diabetes Mellitus , Pie Diabético , Humanos , Pie Diabético/terapia , Desbridamiento/métodos , Cicatrización de Heridas , Ultrasonido , Carga BacterianaRESUMEN
Introducción. Las dermatofitosis son infecciones fúngicas superficiales de epitelios queratinizados. La tinea capitis es una de ellas y afecta a poblaciones escolares vulnerables. Carpinelo es un barrio del área periférica de Medellín con precarias condiciones socioeconómicas. Ante la sospecha de un brote de dermatofitosis, los afectados fueron evaluados. Objetivo. Evaluar clínica y microbiológicamente pacientes del barrio Carpinelo con sospecha de micosis cutáneas para determinar la presencia de un brote por dermatofitos. Materiales y métodos. Se llevó a cabo un estudio descriptivo, de corte longitudinal, con muestreo a conveniencia. Se hizo una búsqueda activa de casos en el Jardín Educativo Buen Comienzo de Carpinelo en niños de la institución y sus familiares. Se evaluaron clínicamente y se tomaron muestras de escamas y cabellos para exámenes directos y cultivos microbiológicos. Se analizó el perfil demográfico, clínico y micológico, con el programa estadístico SPSS™, versión 25. Resultados. Se estudiaron 57 pacientes, 47 eran menores de edad con una media de edad de seis años; se observó una proporción de hombres y mujeres de 2:1. Los pacientes con resultados positivos se diagnosticaron con tinea capitis (78,95 %), tinea faciei (15,79 %) y tinea corporis (10,52 %). El 75,43 % de los pacientes recibió tratamiento previo y de estos el 69,73 % fue con esteroides. El examen directo fue positivo en el 53,84 % y los cultivos en el 46,5 % de los casos. Los agentes aislados fueron: Microsporum canis (77,77 %), Trichophyton spp. (11,11 %), Trichophyton rubrum (5,55 %) y Malassezia spp. (5,55 %). Conclusión. Tinea capitis fue la presentación clínica más común y M. canis el dermatofito más frecuentemente aislado. Llamó la atención el uso de esteroides como primera y única opción del tratamiento empírico' lo cual resalta la importancia del diagnóstico microbiológico para proporcionar la terapia apropiada.
Introduction. Dermatophytoses are superficial fungal infections of the keratinized epithelium like tinea capitis. The latte mainly affects school-vulnerable populations. Carpinelo is a peripheral neighborhood in Medellín with poor socioeconomic conditions and where a suspected tinea capitis outbreak took place. Objective. To study and characterize, clinically and microbiologically, patients with suspected dermatophytosis in Carpinelo. Materials and methods. We carried out a descriptive and longitudinal study with an active case search of tinea capitis in children and their relatives from the Jardín Educativo Buen Comienzo community in Carpinelo. Patients were clinically evaluated, and samples of scales and hair were taken to perform mycological studies with a 10 % potassium hydroxide and culture in Sabouraud and Mycosel agar. We analyzed the data with the statistical program SPSS™. 25 version. Results. Fifty-seven individuals were studied: 47 were children with a mean age of six years and a ratio of 2:1 male to female. Patients with confirmed diagnosis presented the following clinical forms: tinea capitis (78.95%), tinea faciei (15.79%) or tinea corporis (10.52%). Out of the total, 69.76% of the patients had previous treatment with steroids. The direct test was positive in 53.84% of the samples, and 46.15% had positive cultures. The isolated species were: Microsporum canis (77.77%), Trichophyton spp. (11.11%), Trichophyton rubrum (5.55%), and Malassezia spp. (5.55 %). Conclusion.Tinea capitis was the most common clinical form, and M. canis was the most frequently isolated species. The use of steroids as the first and only option for empiric treatment was worth of notice. The findings of this study point out the importance of microbiological diagnosis in choosing the best treatment for the patients.
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Tiña , Dermatomicosis , Tiña del Cuero Cabelludo , Brotes de EnfermedadesRESUMEN
La rifampicina es un medicamento ampliamente utilizado para el tratamiento de diversas infecciones bacterianas con un amplio espectro de efectos adversos que varían desde reacciones leves hasta potencialmente fatales; la anemia hemolítica es un efecto adverso escasamente reportado en la literatura pero que puede tener un desenlace potencialmente fatal, reportamos así un caso de anemia hemolítica autoinmune asociada a lesión renal aguda en una paciente joven en segunda fase de tratamiento para tuberculosis pulmonar.
Summary Rifampicin is a widely used drug for the treatment of various infectious diseases with a broad spectrum of adverse reaction ranging from mild to life-threatening manifestations; hemolytic anemia is an adverse effect rarely reported in the literature, but it can have a potentially fatal outcome. Thus, we report a case of autoimmune hemolytic anemia associated with acute kidney injury in a young patient in the second phase of treatment for pulmonary tuberculosis.
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Humanos , Femenino , AdultoRESUMEN
El síndrome destructivo de línea media es un grupo de enfermedades inflamatorias y tumorales destructivas del área centrofacial, entre las cuales la paracoccidioidomicosis es una de las etiologías a considerar en los países del trópico. La paracoccidioidomicosis es causada por hongos del género Paracoccidioides. Su forma de blastoconidia favorece la diseminación hematógena, afectando diversos tejidos como glándulas suprarrenales, tejido retículo-endotelial o mucosa oral, esta última donde puede manifestarse como un síndrome destructivo de línea media. Presentamos un caso de paracoccidioidomicosis con afección en cavidad oral, el cual debutó como un síndrome destructivo de línea media crónico, asociado a compromiso grave de la vía aérea que requirió manejo quirúrgico por riesgo de obstrucción y presentó mejoría con manejo antimicótico sistémico.
Summary Midline destructive disease is a group of severe and destructive inflammatory and tumor diseases of the midface area, among which paracoccidioidomycosis is one of the main etiologies in tropical countries. Paracoccidioidomycosis is an endemic mycosis caused by fungi of the genus Paracoccidioides. Its blastoconidia form favors hematogenous spread, affecting various tissues such as adrenal glands, reticulo-endothelial tissue, or oral mucosa, where it can manifest as a destructive midline syndrome. We present a case of paracoccidioidomycosis with affection in the oral cavity, which debuted as a chronic midline destructive disease with sever airway compromise that required surgical treatment for the risk of obstruction of the airway. The patient received systemic treatment with good response.
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HumanosRESUMEN
A systematic review and meta-analysis were carried out to investigate the effect of ultrasound-assisted wound (UAW) debridement in patients with diabetic foot ulcers (DFUs). All selected studies were evaluated using the Cochrane risk of bias tool to assess the risk of bias for randomized controlled trials. PubMed and Web of Science were searched in October 2021 to find randomized clinical trials (RCT) assessing the effect of UAW debridement on DFUs. RevMan v5.4. was used to analyze the data with the Mantel-Haenszel method for dichotomous outcomes. A total of 8 RCT met our inclusion criteria, with 263 participants. Concerning the healing rate comparing UAW versus the control group, a meta-analysis estimated the pooled OR at 2.22 (95% CI 0.96-5.11, p = 0.06), favoring UAW debridement, with low heterogeneity (x2 = 7.47, df = 5, p = 0.19, I2 = 33%). Time to healing was similar in both groups: UAW group (14.25 ± 10.10 weeks) versus the control group (13.38 ± 1.99 weeks, p = 0.87). Wound area reduction was greater in the UAW debridement group (74.58% ± 19.21%) than in the control group (56.86% ± 25.09%), although no significant differences were observed between them (p = 0.24). UAW debridement showed higher healing rates, a greater percentage of wound area reduction, and similar healing times when compared with placebo (sham device) and standard of care in patients with DFUs, although no statistically significant differences were observed between groups.
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Regulation of maximum levels of cadmium in chocolate is an issue for cacao exportation from many parts of Latin America, including Colombia. These limits are related to the final product, but buyers often request maximum levels of Cd in the beans. However, to date, there is neither a clear understanding of the relationship between the specified levels of Cd in chocolate and cocoa derivatives and levels in harvested beans or soil nor of the effect of post-harvest processes on the levels of Cd in the final product. To address this, the fate of Cd concentration from soil to chocolate bar was followed in a single farm in Santander district, Colombia. The concentration of Cd in soils was measured using ICP-OES and correlated with soil pH, soil organic matter (SOM), and the use of P-based fertilisers. Cd concentrations were also measured in unfermented seeds, fermented and dried beans, shell, nibs, and chocolate. SOM (2.93-3.78%), soil pH (4.7-4.9), soil P concentration (120-132 mg kg-1) affect Cd availability. However, it is still unclear whether Cd concentration of P-based fertilisers (3-30 mg kg-1) is important or not. While post-harvest treatments did not affect the Cd concentration of beans (4.17 ± 0.8 mg kg-1 on average), the removal of the shell (6.57 mg kg-1) from the nibs (3.28 mg kg-1), as well as the percentage of cocoa mass used contributes to a reduction in Cd concentration in the chocolate bar (1.60 mg kg-1). This study provides clear indications on where research into mitigation measures should be focussed, as well as indicating the importance of carrying out analyses for Cd in the nib or cacao mass, rather than the whole bean, reducing Cd concentration by up to 40%.
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Cacao , Chocolate , Contaminantes del Suelo , Cadmio/análisis , Chocolate/análisis , Colombia , Fermentación , Fertilizantes/análisis , Suelo , Contaminantes del Suelo/análisisRESUMEN
The palm tribe Phytelepheae form a clade of three genera and eight species whose phylogenetic relationships and historical biogeography are not fully understood. Based on morphological similarities and phylogenetic relatedness, it has been suggested that Phytelephas seemannii and Phytelephas schottii are synonyms of Phytelephas macrocarpa, implying the existence of only six species within the Phytelepheae. In addition, uncertainty in their phylogenetic relationships in turn results in blurred biogeographic history. We inferred the phylogenomic relationships in the Phytelepheae by target-capturing 176 nuclear genes and estimated divergence times by using four fossils for time calibration. We lastly explored the biogeographic history of the tribe by inferring its ancestral range evolution. Our phylogenomic trees showed that P. seemannii and P. schottii are not closely related with P. macrocarpa, and therefore, support the existence of eight species in the Phytelepheae. The ancestor of the tribe was widely-distributed in the Chocó, Magdalena, and Amazonia during the Miocene at 19.25 Ma. Early diversification in Phytelephas at 5.27 Ma could have occurred by trans-Andean vicariance after the western Andes uplifted rapidly at â¼ 10 Ma. Our results show the utility of phylogenomic approaches to shed light on species relationships and their biogeographic history.
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Arecaceae , Verduras , Arecaceae/genética , Brasil , Filogenia , FilogeografíaRESUMEN
The fine flavor cocoa (FFC) market offers cocoa farmers better monetary and nonmonetary benefits than the bulk market. In this work, during cocoa fermentation, flavor formation was studied at different fermentation times based on sensory profiles, volatile compound contents and untargeted metabolomics. It was observed that chocolate quality is influenced by fermentation time. Thus, at 72 h, the sensory profiles showed no outstanding attributes, while at 96 h, the global quality presented a stronger influence of fine attributes, such as fruitiness, florality, spices and nuttiness. Finally, at 120/144 h, these FFC features diminished. Metabolomic fingerprint of cocoa beans (related to peptides, sugars, amino acids, and phenolic compounds) and the volatile fingerprint of chocolate showed a change according to the fermentation time. This allowed the proposal of 96 h as the optimal fermentation time to produce FFC beans. Additionally, 20 volatiles and 48 discriminating metabolites were defined as potential quality biomarkers.
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Cacao , Chocolate , Compuestos Orgánicos Volátiles , Chocolate/análisis , Fermentación , Aromatizantes/análisis , Odorantes/análisisRESUMEN
Despite the importance of fermentation for cocoa quality, process parameters are not controlled under spontaneous conditions at farms. This study evaluates the influence of spontaneous fermentation and processing under laboratory-controlled conditions using the acidic reagents acetic and lactic acids on the cocoa quality of two cultivars, FEAR 5 and CCN 51, at the sensory and metabolomic levels. Under spontaneous conditions, cocoa differs in flavour quality. While FEAR 5 produces chocolate with good global quality, chocolate made with CCN 51 does not have outstanding quality attributes. Transformation under controlled conditions with acidic reagents increases the perception of fine aromatic notes such as fruity, nutty and floral attributes in chocolates made from both cultivars of cocoa. Metabolomic profiles allowed grouping of cocoa samples as a function of postharvest treatment. Twenty-five differential metabolites were identified during the postharvest processes, and these metabolites may be related to the expression of fine sensory attributes; however, more research is needed.
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Cacao , Chocolate , Fermentación , Aromatizantes , GustoRESUMEN
Mangosteen peel is a source of natural phenolic antioxidants. During processing, the quality and quantity of these compounds in the final product are altered. Sometimes, the important causal relationships are not easy to establish and thus process management is difficult. This is especially true when biochemical changes can occur as in the case of the drying and extraction process of bioactive materials. The aim of this work was to formulate and solve an optimization problem in order to obtain the appropriate values of the operating conditions that maximize the antioxidant capacity of the dried mangosteen peel extracts. The drying process was analyzed under different drying air temperatures (T) (50â, 60â, 70â and 80â) at air velocity of 1 ms-1. The extraction process was done under conventional and ultrasound-assisted extraction at 400 W. Antioxidant capacity was measured by 1,1-diphenyl-2-picrylhydrazyl assay. To solve the optimization problem formulated, an artificial neural network was developed. The resolution of the optimization problem allowed the establishment of the optimal operating conditions of the process, maximizing the antioxidant capacity values depending on the characteristics of the process. Results showed that the best operating conditions to maximize the antioxidant capacity of mangosteen peels were a drying temperature of 70â and using high-power ultrasound as extraction method.
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Garcinia mangostana , Antioxidantes , Frutas/química , Fenoles/análisis , Extractos VegetalesRESUMEN
Andean orogenesis has driven the development of very high plant diversity in the Neotropics through its impact on landscape evolution and climate. The analysis of the intraspecific patterns of genetic structure in plants would permit inferring the effects of Andean uplift on the evolution and diversification of Neotropical flora. In this study, using microsatellite markers and Bayesian clustering analyses, we report the presence of four genetic clusters for the palm Oenocarpus bataua var. bataua which are located within four biogeographic regions in northwestern South America: (a) Chocó rain forest, (b) Amotape-Huancabamba Zone, (c) northwestern Amazonian rain forest, and (d) southwestern Amazonian rain forest. We hypothesize that these clusters developed following three genetic diversification events mainly promoted by Andean orogenic events. Additionally, the distinct current climate dynamics among northwestern and southwestern Amazonia may maintain the genetic diversification detected in the western Amazon basin. Genetic exchange was identified between the clusters, including across the Andes region, discarding the possibility of any cluster to diversify as a distinct intraspecific variety. We identified a hot spot of genetic diversity in the northern Peruvian Amazon around the locality of Iquitos. We also detected a decrease in diversity with distance from this area in westward and southward direction within the Amazon basin and the eastern Andean foothills. Additionally, we confirmed the existence and divergence of O. bataua var. bataua from var. oligocarpus in northern South America, possibly expanding the distributional range of the latter variety beyond eastern Venezuela, to the central and eastern Andean cordilleras of Colombia. Based on our results, we suggest that Andean orogenesis is the main driver of genetic structuring and diversification in O. bataua within northwestern South America.
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BACKGROUND: A screening for malaria parasites was conducted with asymptomatic residents in Colombia. METHODS: A descriptive study was carried out in December 2012 in four municipalities of Urabá region in Colombia. A convenience sample of 400 subjects was selected. Participants responded to a survey regarding epidemiological data and blood samples were taken from capillary blood obtained by finger prick for thick smear, rapid diagnostic test (RDT), and polymerase chain reaction (PCR). RESULTS: 399 subjects aged 0.2-98 years were studied (median 22; 221 female (55%)). Episodes of malaria in the last year confirmed by thick film were reported by 47 participants (12%). In 399 samples tested by RDT 4 (1%) were positive (1 with P. falciparum, 3 with P. vivax), and 3 were confirmed by PCR. In 399 thick blood smears examined 5 (1.3%) were positive (2 with P. falciparum, 3 with P. vivax), and 3 were confirmed by PCR. In 227 samples, PCR showed 6 (2.6%) positive samples. The parasitaemia was below 1,440 parasites/µL. The best agreement between diagnoses was found between the RDT and thick blood smears (Kappa = 0.75). CONCLUSION: Plasmodial afebrile infection was found in 2% of the studied population, by three diagnostic methods, in residents from a low endemic malaria region in Colombia.
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The growth rate of four strains of Pseudomonas putida, KT2440, KT2442, KTH2, and KTH2 (pESOX3), under different fluid dynamic conditions has been studied. The cultures were conducted in a stirred tank bioreactor by changing the stirrer speed. Several process variables, such as biomass concentration, dissolved oxygen concentration, oxygen mass transfer rate and oxygen uptake rate, have been measured or calculated. Also cell viability was determined by viable colony counting in Petri dishes and culture samples were subjected into a transmission electron microscopy analysis, in order to describe the integrity of the individual cells. The experimental results show that the genetically modified organisms, the strains KTH2 and KTH2 (pESOX3), present a different growth under low agitation conditions, and low oxygen supply level, while the growth of the wild type strains, KT2440 and KT2442, followed the typical sigmoidal evolution that could be described by the logistic equation. The presence of outer membrane vesicles has been observed in the GMO strains. When the cultures were conducted at low stirrer speed, and so at low oxygen transfer rate, these vesicles were detected, indicating the bacterial response to oxidative stress, caused by the catalytic activity of the HpaC enzyme. For all of the strains tested, no hydrodynamic stress has been detected, even at very high agitation levels. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:900-909, 2018.
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Oxígeno/metabolismo , Pseudomonas putida/crecimiento & desarrollo , Pseudomonas putida/fisiología , Biomasa , Reactores Biológicos/microbiologíaRESUMEN
BACKGROUND: Urinalysis is a poorly reviewed diagnostic tool in malaria patients; its application can show the presence of severe malaria. METHODS: Urinalysis was performed in a total of 620 patients diagnosed with malaria by thick blood smear; complications were classified according to WHO major criteria for severity and minor criteria according to the Colombian malaria guideline. RESULTS: Severe or moderate clinical complications were diagnosed in 31.1% of patients, hepatic dysfunctions were diagnosed in 25.8%, anemia was diagnosed in 9.8%, thrombocytopenia was diagnosed in 7.7%, renal dysfunction was diagnosed in 4.8%, neurological and pulmonary complications were diagnosed in 2.1% and 2.4%, hypoglycemia was diagnosed in 1.1% of patients with blood glucose analysis, and acidosis was diagnosed in 10 of 25. Bilirubinuria was found in 24.3%, associated with urobilinuria, proteinuria, and increased specific gravity; urobilinuria was found in 30.6% associated with elevated serum bilirubin and alanine aminotransferase; 39.2% had proteinuria, associated with higher blood urea nitrogen, serum bilirubin, aspartate, alanine-transaminase, hematuria, and increased specific gravity. Severe or moderate liver and renal complications were associated with proteinuria and bilirubinuria. Urobilinuria was associated with thrombocytopenia and neurological and hepatic dysfunction. Ketonuria was associated with neurological dysfunctions. CONCLUSIONS: The most frequent alterations in the urinalysis were bilirubinuria, proteinuria, urobilinuria, and increased specific gravity, related to thrombocytopenia and liver, kidney, and neurological alterations.
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This article shows that a simple monetary incentive can dramatically reduce electric energy consumption (EEC) in the residential sector and simultaneously achieve a more desirable allocation of EEC costs. The analyses are based on data from a policy experiment conducted in 2011 and 2012 by a private housing company in about 1,800 apartments. Roughly 800 of the tenants (treatment group) were subject to a change from having unlimited EEC included in their rent to having to pay the market price for their own EEC. This change was achieved by installing EEC meters in each apartment. Tenants in the other 1,000 apartments (control group) experienced no policy change and were subject to apartment-level billing and metering during the entire study period. Using a quasiexperimental research design and daily data on EEC from 2007 to 2015, we estimate that apartment-level billing and metering permanently reduce EEC by about 25%. Moreover, we show that households reduce EEC immediately after being informed that they will be billed for EEC, the reduction is larger when the production cost is higher, and the reduction in EEC comes almost exclusively from households with very high EEC before the policy change. Finally, we show that apartment-level billing and metering are cost-effective, with a cost per reduced kilowatt hour of US$0.01, and for each invested dollar, the social value of reductions in air pollution, including CO2 emissions, is $2.
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Previous works on European sea bass have determined that long-term exposure to restrictive feeding diets alters the rhythms of some reproductive/metabolic hormones, delaying maturation and increasing apoptosis during gametogenesis. However, exactly how these diets affect key genes and hormones on the brain-pituitary-gonad (BPG) axis to trigger puberty is still largely unknown. We may hypothesize that all these signals could be integrated, at least in part, by the kisspeptin system. In order to capture a glimpse of these regulatory mechanisms, kiss1 and kiss2 mRNA expression levels and those of their kiss receptors (kiss1r, kiss2r) were analyzed in different areas of the brain and in the pituitary of pubertal male sea bass during gametogenesis. Furthermore, other reproductive hormones and factors as well as the percentage of males showing full spermiation were also analyzed. Treated fish fed maintenance diets provided evidence of overexpression of the kisspeptin system in the main hypophysiotropic regions of the brain throughout the entire sexual cycle. Conversely, Gnrh1 and gonadotropin pituitary content and plasma sexual steroid levels were downregulated, except for Fsh levels, which were shown to increase during spermiation. Treated fish exhibited lower rates of spermiation as compared to control group and a delay in its accomplishment. These results demonstrate how the kisspeptin system and plasma Fsh levels are differentially affected by maintenance diets, causing a retardation, but not a full blockage of the reproductive process in the teleost fish European sea bass. This suggests that a hormonal adaptive strategy may be operating in order to preserve reproductive function in this species.
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Lubina/fisiología , Proteínas de Peces/fisiología , Alimentos , Kisspeptinas/fisiología , Reproducción/fisiología , Maduración Sexual/fisiología , Animales , Lubina/genética , Proteínas de Peces/genética , Hormona Folículo Estimulante/sangre , Hormona Folículo Estimulante/metabolismo , Expresión Génica , Hormona Liberadora de Gonadotropina/metabolismo , Gonadotropinas/sangre , Gonadotropinas/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/genética , Hormona Luteinizante/metabolismo , Masculino , Mesencéfalo/metabolismo , Hipófisis/metabolismo , Prosencéfalo/metabolismo , Receptores de HFE/genética , Receptores de HFE/fisiología , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiología , Receptores de HL/genética , Receptores de HL/fisiología , Reproducción/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estaciones del Año , Maduración Sexual/genética , Espermatogénesis/genética , Espermatogénesis/fisiologíaRESUMEN
In this study, we report the cloning of three transcripts for leptin receptor in the European sea bass, a marine teleost of economic interest. The two shortest variants, generated by different splice sites, encode all functional extracellular and intracellular domains but missed the transmembrane domain. The resulting proteins are therefore potential soluble binding proteins for leptin. The longest transcript (3605bp), termed sblepr, includes all the essential domains for binding and transduction of the signal. Thus, it is proposed as the ortholog for the human LEPR gene, the main responsible for leptin signaling. Phylogenetic analysis shows the sblepr clustered within the teleost leptin receptor group in 100% of the bootstrap replicates. The neuroanatomical localization of sblepr expressing cells has been assessed by in situ hybridization in brains of sea bass of both sexes during their first sexual maturation. At histological level, the distribution pattern of sblepr expressing cells in the brain shows no clear differences regarding sex or reproductive season. Transcripts of the sblepr have a widespread distribution throughout the forebrain and midbrain until the caudal portion of the hypothalamus. A high hybridization signal is detected in the telencephalon, preoptic area, medial basal and caudal hypothalamus and in the pituitary gland. In a more caudal region, sblepr expressing cells are identified in the longitudinal torus. The expression pattern observed for sblepr suggests that in sea bass, leptin is very likely to be involved in the control of food intake, energy reserves and reproduction.
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Lubina/metabolismo , Receptores de Leptina/metabolismo , Animales , Lubina/genética , Ingestión de Alimentos , Europa (Continente) , Femenino , Masculino , Neuroanatomía , Filogenia , Reproducción , Distribución TisularRESUMEN
Puberty is the process by which an immature animal acquires the ability to reproduce for the first time; its onset occurs soon after sexual differentiation and is characterized by the beginning of gametogenesis in both sexes. Here we present new insights on when and how the onset of puberty occurs in male European sea bass, its dependence on reaching a critical size, and how it can be controlled by photoperiod, revealing the existence of a photolabile period with important applications in aquaculture. Regarding size, apparently only European sea bass above a certain size threshold attain the ability to carry out gametogenesis during their first year of life, while their smaller counterparts fail to do so. This could imply that fish need to achieve an optimal threshold of hormone production, particularly from the kisspeptin/Gnrh/Gth systems, in order to initiate and conclude puberty. However, a long-term restricted feeding regime during the second year of life did not prevent the onset of puberty, thus suggesting that the fish are able to maintain the reproductive function, even at the expense of other functions. Finally, the study of daily hormonal rhythms under different photoperiod regimes revealed the equivalence between their core values and those of seasonal rhythms, in such a way that the daily rhythms could be considered as the functional units of the seasonal rhythms.