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1.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38396884

RESUMEN

Bruton's tyrosine kinase (BTK) inhibitors have revolutionized the landscape for the treatment of hematological malignancies, solid tumors, and, recently, autoimmune disorders. The BTK receptor is expressed in several hematopoietic cells such as macrophages, neutrophils, mast cells, and osteoclasts. Similarly, the BTK receptor is involved in signaling pathways such as chemokine receptor signaling, Toll-like receptor signaling, and Fc receptor signaling. Due to their unique mechanism, these agents provide a diverse utility in a variety of disease states not limited to the field of malignant hematology and are generally well-tolerated.


Asunto(s)
Neoplasias Hematológicas , Neoplasias , Humanos , Agammaglobulinemia Tirosina Quinasa , Transducción de Señal , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico
2.
J Hum Evol ; 120: 140-202, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29153333

RESUMEN

This paper reports the results of renewed fieldwork at the HWK EE site (Olduvai Gorge, Tanzania). HWK EE is positioned across the boundary between Lower and Middle Bed II, a crucial interval for studying the emergence of the Acheulean at Olduvai Gorge. Our excavations at HWK EE have produced one of the largest collections of fossils and artefacts from any Oldowan site, distributed across several archaeological units and a large excavation surface in four separate trenches that can be stratigraphically correlated. Here we present the main stratigraphic and archaeological units and discuss site formation processes. Results show a great density of fossils and stone tools vertically through two stratigraphic intervals (Lemuta and Lower Augitic Sandstone) and laterally across an area of around 300 m2, and highlight the confluence of biotic and abiotic agents in the formation of the assemblage. The large size and diversity of the assemblage, as well as its good preservation, qualify HWK EE as a reference site for the study of the late Oldowan at Olduvai Gorge and elsewhere in Africa. In addition, the description of the stratigraphic and archaeological sequence of HWK EE presented in this paper constitutes the foundation for further studies on hominin behavior and paleoecology in Lower and Middle Bed II.


Asunto(s)
Arqueología , Evolución Cultural , Ambiente , Fósiles , Hominidae , Animales , Paleontología , Tanzanía , Tecnología
3.
Biol Blood Marrow Transplant ; 21(11): 1926-31, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26087475

RESUMEN

High-dose chemotherapy followed by autologous hematopoietic cell transplantation (HCT) improves outcomes in relapsed lymphoma, but the relative efficacy of different preparative regimens is not well defined. We included patients undergoing autologous HCT using BEAM (carmustine, 300 mg/m(2), etoposide, cytarabine, and melphalan) or BEP (carmustine 600 mg/m(2), etoposide, and cisplatin) between January 2004 and December 2013; 65 patients received BEP and 64 patients BEAM. Both cohorts were similar for advanced-stage disease, extranodal and bulky disease, and prior therapies. Median neutrophil and platelet engraftment was 10 and 20 days for both regimens, respectively. Febrile neutropenia, serum creatinine concentration increase, and electrolyte abnormalities were more frequent with BEP. Incidence of carmustine pneumonitis was not higher with BEP, likely the result of corticosteroid prophylaxis, although 2 cases of fatal pneumonitis were observed after BEP. One-year nonrelapse mortality was 6.8% after BEP and 0% after BEAM (P = .379). After a median follow-up of 39.4 months (range, 1 to 128), 4-year rates of overall survival (OS) after BEP and BEAM were 80.4% and 72.3%, respectively (P = .611). Diffuse large B cell lymphoma patients transplanted after early relapse post-rituximab-based first-line therapy presented 3-year rates of OS and progression-free survival (PFS) of 73.8% and 65%, respectively. There were no statistically significant differences in the OS and PFS of follicular lymphoma, mantle cell lymphoma, or Hodgkin lymphoma. BEP is a valid alternative to BEAM in autologous HCT. Although associated with more renal and electrolytic toxicities, BEP results in similar disease control and long-term survival as BEAM. Prospective studies are needed to confirm whether intensification of conditioning regimens for autologous HCT can improve disease control in high-risk relapsed lymphoma patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Enfermedad de Hodgkin/terapia , Linfoma Folicular/terapia , Linfoma de Células B Grandes Difuso/terapia , Linfoma de Células del Manto/terapia , Linfoma no Hodgkin/terapia , Acondicionamiento Pretrasplante/métodos , Adolescente , Adulto , Anciano , Carmustina/uso terapéutico , Cisplatino/uso terapéutico , Citarabina/uso terapéutico , Etopósido/uso terapéutico , Femenino , Supervivencia de Injerto , Enfermedad de Hodgkin/inmunología , Enfermedad de Hodgkin/mortalidad , Enfermedad de Hodgkin/patología , Humanos , Linfoma Folicular/inmunología , Linfoma Folicular/mortalidad , Linfoma Folicular/patología , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células del Manto/inmunología , Linfoma de Células del Manto/mortalidad , Linfoma de Células del Manto/patología , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Masculino , Melfalán/uso terapéutico , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Riesgo , Rituximab/uso terapéutico , Análisis de Supervivencia , Trasplante Autólogo
4.
J Clin Gastroenterol ; 48(2): 145-52, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23751853

RESUMEN

BACKGROUND: Endoscopic necrosectomy for necrotizing pancreatitis has been increasingly used as an alternative to surgical or percutaneous interventions. The use of fully covered esophageal self-expandable metallic stents may provide a safer and more efficient route for internal drainage. The aim of this study was to evaluate the safety and efficacy of endoscopic treatment of pancreatic necrosis with these stents. METHODS: A retrospective study at 2 US academic hospitals included patients with infected pancreatic necrosis from July 2009 to November 2012. These patients underwent transgastric placement of fully covered esophageal metallic stents draining the necrosis. After necrosectomy, patients underwent regular sessions of endoscopic irrigation and debridement of cystic contents. The efficacy endpoint was successful resolution of infected pancreatic necrosis without the need for surgical or percutaneous interventions. RESULTS: Seventeen patients were included with the mean age of 41±12 years. A mean of 5.3±3.4 sessions were required for complete drainage and the follow-up period was 237.6±165 days. Etiology included gallstone pancreatitis (6), alcohol abuse (6), s/p distal pancreatectomy (2), postendoscopic retrograde cholangiopancreatography pancreatitis (1), medication-induced pancreatitis (1), and hyperlipidemia (1). Mean size of the necrosis was 14.8 cm (SD 5.6 cm), ranging from 8 to 19 cm. Two patients failed endoscopic intervention and required surgery. The only complication was a perforation during tract dilation, which was managed conservatively. Fifteen patients (88%) achieved complete resolution. CONCLUSIONS: Endoscopic necrosectomy with covered esophageal metal stents is a safe and successful treatment option for infected pancreatic necrosis.


Asunto(s)
Endoscopía del Sistema Digestivo/métodos , Pancreatitis Aguda Necrotizante/cirugía , Stents , Adolescente , Adulto , Desbridamiento , Drenaje/métodos , Endoscopía del Sistema Digestivo/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis Aguda Necrotizante/microbiología , Pancreatitis Aguda Necrotizante/patología , Estudios Retrospectivos , Stents/efectos adversos , Irrigación Terapéutica , Adulto Joven
5.
F1000Res ; 12: 747, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38571570

RESUMEN

Background: The paper describes lead ion adsorption on variable charge oxidic calcined substrates with chemically modified surfaces. Amphoteric oxides of iron, aluminum, titanium, and manganese, change their surface electric charge after acid or alkaline treatment, letting cationic or anionic adsorption reactions from aqueous solutions. This property allows using them as adsorbing substrate for heavy metals retention in water treatment systems. Methods: Substrate was prepared by extruding cylindrical strips from a saturate paste of the oxidic lithological material-OLM; dries it up and thermally treated by calcination. The study was performed by triplicated trial, on batch mode, using 2 grams samples of treated with NaOH 0.1N and non-treated substrate. Lead analysis was performed by AAS-GF. Freundlich and Langmuir models were used to fit results. Comparing differential behavior between treated and non-treated substrates showed the variable charge nature of the OLM. Results: Results show L-type isotherms for the adsorption of Pb(II) ions on the activated substrate, suggesting good affinity between Pb(II) ions and OLM's surface. Average value of adsorption capacity ( K) for activated substrate (1791.73±13.06), is around four times greater than the non-activated substrate (491.54±31.97), during the adsorption reaction, 0.35 and 0.26 mmolH + of proton are produced on the activated and non-activated substrate respectively using a 1 mM Pb(II) solution and 72.2 and 15.6 mmolH + using a 10 mM Pb(II) solution. This acidification agrees with the theoretic model of transitional metals chemisorption on amphoteric oxides, present in lithological material used for the preparation of adsorbent substrates, confirming the information given by the L-type isotherms. Conclusions: Results suggest that these variable charge oxidic adsorbent substrate show great potential as an alternative technique for water treatment at small and medium scale using granular filtration system. The easiness and low price make them suitable to apply in rural media where no treating water systems is available.


Asunto(s)
Plomo , Óxidos , Adsorción , Concentración de Iones de Hidrógeno , Óxidos/química , Iones
6.
Circ Res ; 107(11): 1374-86, 2010 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-21088285

RESUMEN

RATIONALE: The turnover of cardiomyocytes in the aging female and male heart is currently unknown, emphasizing the need to define human myocardial biology. OBJECTIVE: The effects of age and gender on the magnitude of myocyte regeneration and the origin of newly formed cardiomyocytes were determined. METHODS AND RESULTS: The interaction of myocyte replacement, cellular senescence, growth inhibition, and apoptosis was measured in normal female (n=32) and male (n=42) human hearts collected from patients 19 to 104 years of age who died from causes other than cardiovascular diseases. A progressive loss of telomeric DNA in human cardiac stem cells (hCSCs) occurs with aging and the newly formed cardiomyocytes inherit short telomeres and rapidly reach the senescent phenotype. Our data provide novel information on the superior ability of the female heart to sustain the multiple variables associated with the development of the senescent myopathy. At all ages, the female heart is equipped with a larger pool of functionally competent hCSCs and younger myocytes than the male myocardium. The replicative potential is higher and telomeres are longer in female hCSCs than in male hCSCs. In the female heart, myocyte turnover occurs at a rate of 10%, 14%, and 40% per year at 20, 60, and 100 years of age, respectively. Corresponding values in the male heart are 7%, 12%, and 32% per year, documenting that cardiomyogenesis involves a large and progressively increasing number of parenchymal cells with aging. From 20 to 100 years of age, the myocyte compartment is replaced 15 times in women and 11 times in men. CONCLUSIONS: The human heart is a highly dynamic organ regulated by a pool of resident hCSCs that modulate cardiac homeostasis and condition organ aging.


Asunto(s)
Células Madre Adultas/citología , Células Madre Adultas/fisiología , Diferenciación Celular/fisiología , Senescencia Celular/fisiología , Corazón/fisiología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/fisiología , Muerte Celular/fisiología , Células Cultivadas , Femenino , Corazón/anatomía & histología , Humanos , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Adulto Joven
7.
Ann Hepatol ; 11(2): 222-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22345339

RESUMEN

BACKGROUND: Liver transplantation is the only therapy for end-stage liver disease. Cirrhosis secondary to autoimmune hepatitis (AIH) is an indication in 4-6% of adult transplants. AIMS: To describe the outcomes and recurrence of AIH in liver transplant patients. MATERIAL AND METHODS: Twenty patients were retrospectively studied. RESULTS: The female/male ratio was 3:1, the median age was 36.7 years (range, 16 to 39 years), and the median MELD score was 18.5. According to serological analysis, 19 patients were AIH type 1 and one patient was AIH type 2. AIH was associated with human leukocyte antigen (HLA) DR13+ and DR4+. The overall 5-year patient and graft survival rates were 94 and 85%, respectively. Three (15.7%) cases of recurrent AIH were diagnosed based on histological evidence. Clinical and histological features of acute and chronic rejection were present in four (20%) and three (16.6%) patients, respectively. CONCLUSION: AIH frequently affected young women, was the most frequent indication for liver transplantation. Rejection and recurrence were commonly associated with AIH, but did not affect patient survival. No significant relationship between HLA-DR type and recurrence was found. Rapid progression to cirrhosis should be considered in severe recurrences.


Asunto(s)
Subtipos Serológicos HLA-DR/inmunología , Antígeno HLA-DR4/inmunología , Hepatitis Autoinmune/cirugía , Cirrosis Hepática/cirugía , Trasplante de Hígado , Adolescente , Adulto , Supervivencia sin Enfermedad , Femenino , Rechazo de Injerto , Supervivencia de Injerto , Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/inmunología , Humanos , Cirrosis Hepática/etiología , Masculino , Persona de Mediana Edad , Perú , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
8.
Arch Latinoam Nutr ; 60(4): 405-10, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21866692

RESUMEN

Honey is the most popular bee product used by man, with nutritional and medicinal purposes. Its great diversity is attributed to numerous factors (bee type, visited flora, environment, and management). The quality of honey is controlled with routine parameters (free acidity, diastase activity, reducing sugars, ash, water, hydroxymethyfurfural, and sucrose contents). Besides the biochemical quality control, a functional profile is also important for pharmacological applications. In this work, bioactive indicators such as the antioxidant activity, flavonoid and polyphenol contents were evaluated by spectrophotometry, and correlated to the content of six bioelements (Ca, Cu, Fe, Mg, Mn, Zn) measured by atomic absorption spectroscopy, tandem FI-FAAS, in 14 unifloral Czech honeys. The antioxidant activity was 43.13 +/- 53.72 micromoles TEAC/100 g honey. The flavonoid content was 5.18 +/- 4.19 mg QE/100 g, and the polyphenol content was 45.38 +/- 27.20 mg GAE/100 g. Buckwheat honey showed the highest values for these indicators of bioactivity, the acacia honeys the lowest, and the rest of the honeys were comprised between both of them. Honey content of bioelements was 138.19 +/- 55.57 ppm Ca (min 77.11-max 261.65), 0.33 +/- 0.41 ppm Cu (min 0.00-max 1.37), 2.95 +/- 1.10 ppm Fe (min 1.34-max 5.36), 35.08 +/- 29.59 ppm Mg (min 8.76-128.06), 4.93 +/- 3.99 ppm Mn (min 0.34-max 11.31), 1.07 +/- 0.56 ppm Zn (min 0.49-max 2.52). The antioxidant activity of honey was significantly correlated to its content of cupper, iron, magnesium, manganese and zinc, but was not correlated to calcium.


Asunto(s)
Antioxidantes/análisis , Flavonoides/análisis , Flores/clasificación , Miel/análisis , Metales Alcalinotérreos/análisis , Metales Pesados/análisis , Polifenoles/análisis , Animales , Indicadores y Reactivos , Espectrofotometría Atómica
9.
Sci Total Environ ; 703: 135517, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31767302

RESUMEN

Diatom assemblages are used widely as indicators of environmental conditions. They have been particularly useful in the assessment of some acute environmental problems such as water acidification, eutrophication and salinisation. High mountain lakes are currently a research focus as sentinels of global change, predominantly of long-distance atmospheric pollution and climate warming. The diatom assemblages in these lakes are extremely rich, and the sediment record provides short and long historical perspectives of the changes. We investigated the relative sensitivity of diatoms to the main environmental gradients found in mountain lakes and evaluated the strength and uncertainties for predicting simultaneously several environmental variables associated with these gradients based on a survey of 83 lakes in the Pyrenees. Variables related to the ionic composition and acid-base balance (calcium*, acid neutralizing capacity*, magnesium, sodium, and sulphates), trophic conditions (total phosphorus* and dissolved organic carbon) and physical factors (water temperature*, irradiance at the lake bottom*, and macrophyte cover) explained independently the variation in the diatom assemblages. However, the assemblage predictive capacity of these variables- tested by developing transfer functions (Weighted Averaging- Partial Least Squares) - was only acceptable for a subset of the variables (*). The spatial autocorrelation of the environmental variables had no influence on the performance of the transfer functions except for water temperature, which is highly dependent on altitude. Our results indicate that diatom assemblages have great potential for assessments of multiple environmental variables in mountain lakes and, consequently, in applications of global change surveillance.


Asunto(s)
Diatomeas/fisiología , Monitoreo del Ambiente/métodos , Contaminantes del Agua/análisis , Contaminación Ambiental , Sedimentos Geológicos , Lagos/química , Fósforo , Análisis Espacial , Temperatura
10.
Environ Entomol ; 49(4): 829-837, 2020 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-32514553

RESUMEN

Bioindication is a method to assess environmental conditions using indicator organisms. In Colombia, water quality evaluation is mostly performed following the Biological Monitoring Working Party/Colombia method (BMWP/Col), which uses aquatic macroinvertebrates at the taxonomic family level. Studies on potential bioindicators are important to produce comprehensive information on the requirements of macroinvertebrates and their value for water quality bioindication. We studied the larval ecology of several common genera of Odonata from Colombian freshwater ecosystems and assigned an indicator value to each genus. The physical and chemical water characteristics of 1,022 sites surveyed in Colombia from 2005 to 2016 were analyzed using a principal component analysis (PCA). The relationship between environmental conditions and Odonata genera found was studied using multiple logistic regressions between sample coordinates of the first three axes of the PCA and occurrence of the respective genus. We assigned an indicator value for each genus using the logistic regression and the water quality of samples. The highest indicator values were assigned to genera, which were mainly explained by the PCA axis associated with water quality, showed a high odds ratio to this axis, and were found in ecosystems with excellent water quality. The indicator values suggested for each taxon are, Brechmorhoga Kirby, 1894, 8; Macrothemis Hagen, 1868, 4; Micrathyria Kirby, 1889, 4 (Libellulidae); Progomphus Selys, 1854, 7 (Gomphidae); Acanthagrion Selys, 1876, 4; and Argia Rambur, 1842, 7 (Coenagrionidae). Differences in water quality preferences in genera of the same family suggest that higher taxonomic resolution may allow more detailed environmental assessments.


Asunto(s)
Odonata , Animales , Colombia , Ecología , Ecosistema , Monitoreo del Ambiente , Larva
11.
Endosc Ultrasound ; 8(3): 151-160, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31134899

RESUMEN

EUS-guided drainage is a safe and efficacious endoscopic technique for biliary, pancreatic, and gallbladder decompression. Recent literature has described many successful procedural techniques and devices to achieve EUS-guided drainage. This consortium gathering advanced endoscopists with expertise in both ultrasonography and therapeutic endoscopy, discuss the introduction to learning several EUS-guided drainage approaches, devices, and technology involved, possible obstacles to certain procedural and all potential complications.

12.
Rev. colomb. cancerol ; 24(4): 176-181, oct.-dic. 2020. graf
Artículo en Español | LILACS | ID: biblio-1289189

RESUMEN

Resumen El carcinoma de labio es uno de los más comunes de la cabeza y el cuello. El tipo histológico más frecuente es el carcinoma escamocelular y afecta predominantemente al labio inferior. Existen distintas técnicas para la reconstrucción de los defectos del labio inferior posterior a la resección oncológica, sin embargo, preservar la funcionalidad y la estética de esta zona es un desafío debido a la alta incidencia de xialorrea, microstomia, alteraciones de la continencia y el habla posterior a la reconstrucción. Se presenta un caso de reconstrucción total de labio inferior ampliada hacia el mentón utilizando el triángulo de Burow y que obtuvo buenos resultados funcionales y estéticos.


Abstract Lip carcinoma is one of the most common malignancies in the head and neck region. Squamous-cell carcinoma is the most frequent type of histological cell carcinoma, chiefly affecting the lower lip. Different techniques for reconstructing defects of the lower lip after neoplasia resection are used; however, preserving the functionality and aesthetics of this area poses a challenge due to the anatomical position that causes accumulation of saliva, thus delaying the healing process. We present a total lower lip reconstruction extended towards the chin by using the Burow's triangle, significantly improving functional and aesthetic results.


Asunto(s)
Humanos , Informe de Investigación , Labio , Neoplasias , Carcinoma de Células Escamosas
13.
World J Gastroenterol ; 21(3): 726-41, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25624708

RESUMEN

Endoscopic retrograde cholangiopancreatography (ERCP) is the preferred procedure for biliary and pancreatic drainage. While ERCP is successful in about 95% of cases, a small subset of cases are unsuccessful due to altered anatomy, peri-ampullary pathology, or malignant obstruction. Endoscopic ultrasound-guided drainage is a promising technique for biliary, pancreatic and recently gallbladder decompression, which provides multiple advantages over percutaneous or surgical biliary drainage. Multiple retrospective and some prospective studies have shown endoscopic ultrasound-guided drainage to be safe and effective. Based on the currently reported literature, regardless of the approach, the cumulative success rate is 84%-93% with an overall complication rate of 16%-35%. endoscopic ultrasound-guided drainage seems a viable therapeutic modality for failed conventional drainage when performed by highly skilled advanced endoscopists at tertiary centers with expertise in both echo-endoscopy and therapeutic endoscopy.


Asunto(s)
Enfermedades de las Vías Biliares/terapia , Coledocostomía/métodos , Descompresión/métodos , Drenaje/métodos , Endosonografía , Gastrostomía/métodos , Enfermedades Pancreáticas/terapia , Ultrasonografía Intervencional , Enfermedades de las Vías Biliares/diagnóstico por imagen , Coledocostomía/efectos adversos , Coledocostomía/normas , Descompresión/efectos adversos , Descompresión/normas , Drenaje/efectos adversos , Drenaje/normas , Endosonografía/normas , Gastrostomía/efectos adversos , Gastrostomía/normas , Humanos , Enfermedades Pancreáticas/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Ultrasonografía Intervencional/normas
14.
J Trace Elem Med Biol ; 16(2): 103-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12195724

RESUMEN

Some cationic species (Ca, Mg, Sr, Cu, Zn and Pb) have been determined in temporary teeth (n = 67) sampled from a children population living in Mérida, Venezuela, with a mean age of 87.76 +/- 34.50 months within a range from 29 to 151 months. Each powdered tooth sample was analyzed for calcium, magnesium, strontium and zinc and for copper and lead by atomic absorption spectrometry with flame and electrothermal atomization, respectively. Relations between variables (elements concentration, age, sex, tooth type and caries status) were established using the Pearson correlation matrix and analysis of variance. The mean global concentrations were of 39.25 +/- 5.36; 1.08 +/- 0.81; 89.27 +/- 13.26 and 2.85 +/- 1.14 micrograms/g for Sr, Cu, Zn and Pb and of 208.45 +/- 33.18 and 8.51 +/- 2.05 mg/g for Ca and Mg, respectively. There were no changes in the teeth mineral content with respect to the children age and sex. With respect to the tooth type, there were significant differences only for strontium which varied in the order molars > canines > incisors. Although healthy teeth had higher mineral concentrations than carious teeth, there were not significant differences, proving that both, carious and healthy teeth could be used as indicators of mineral uptake. Magnesium and copper are the elements least related with the others. Significant positive correlations were found between Sr-Zn, Sr-Cu, Sr-Pb, and the only negative correlations were between Ca-Zn and Ca-Pb for the different types of teeth. While the positive association might indicate competition for anionic groups or similar affinity for the same sites in the crystalline structure, the negative correlations showed possible substitutions among the elements.


Asunto(s)
Cationes/análisis , Diente Primario/química , Envejecimiento , Calcio/análisis , Niño , Preescolar , Diente Canino/química , Interpretación Estadística de Datos , Caries Dental , Humanos , Incisivo/química , Plomo/análisis , Magnesio/análisis , Diente Molar/química , Sensibilidad y Especificidad , Caracteres Sexuales , Estroncio/análisis , Venezuela , Zinc/análisis
15.
Acta biol. colomb ; 24(1): 67-85, ene.-abr. 2019. tab, graf
Artículo en Español | LILACS | ID: biblio-989040

RESUMEN

RESUMEN La vegetación riparia es primordial para el funcionamiento de los ecosistemas acuáticos al aportar materia orgánica. Dado que el perifiton juega un rol indispensable en la dinámica de estos ecosistemas y existen pocos trabajos sobre su ecología en el Neotrópico, se planteó la pregunta: ¿Cómo afecta el tipo de cobertura vegetal de la zona riparia, la estructura del fitoperifiton de humedales de la Orinoquía? En noviembre de 2016 se estudiaron 15 humedales con cobertura boscosa y 15 humedales con vegetación herbácea en su zona riparia. Los humedales están ubicados en la zona periurbana de Villavicencio, Meta (Colombia). Se comparó la diversidad algal entre coberturas riparias y se realizaron análisis de Redundancia para determinar que variables ambientales explicaban la composición del fitoperifiton. Se encontraron 467 morfotipos de algas, el 36,2 % perteneció a la clase Zygnematophyceae, 35,3 % a Bacillariophyceae y 16 % a Chlorophyceae. En cuanto a las diatomeas, se encontraron 165 morfoespecies distribuidas en 30 géneros. Eunotia y Pinnularia fueron los más representativos. Los análisis multivariados indicaron que la composición de diatomeas se relacionó con la cobertura vegetal litoral y el carbono orgánico total. El resto del fitoperifiton fue explicado por la temperatura y la conductividad. Modelos de regresión lineal mostraron que la diversidad de diatomeas fue explicada por el número de sustratos, la temporalidad y la cobertura vegetal riparia. Los resultados permiten concluir que en humedales antropizados de la Orinoquía colombiana, el tipo de cobertura vegetal riparia afecta la composición y diversidad de las diatomeas.


ABSTRACT Riparian vegetation is essential for the functioning of aquatic ecosystems by providing organic matter. Given that periphyton plays an indispensable role in the dynamics of these ecosystems and there are few works on its ecology in the Neotropic our research question was: How does the riparian vegetation cover affect the structure of the phytoperiphyton in wetlands of the Orinoquía? In November 2016, we sampled 15 wetlands covered by forest and 15 wetlands covered by herbaceous vegetation in the riparian zone. The wetlands are located in the peri-urban area of Villavicencio, Meta (Colombia). The algal diversity between coverage types was compared and Redundancy Analyses were carried out to determine which environmental variables explain the phytoperiphyton composition. 467 morphotypes of microalgae were found, 36.2 % belonged to the Zygnematophyceae Class, 35.3 % to Bacillariophyceae, and 16 % to Chlorophyceae. 165 morpho-species of diatom distributed in 30 genera were found. Eunotia and Pinnularia were the most representative. The multivariate analyzes indicate that the composition of diatoms was related to the littoral vegetation coverage and the total organic carbon. The rest of the phytoperifiton was explained by temperature and conductivity. Linear regression models showed that the diversity of diatoms was explained by the number of substrates, temporality and the type of riparian coverage. We conclude that in anthropogenic wetlands of the Colombian Orinoquía, the type of riparian vegetation affects the composition and diversity of diatoms.

16.
Rev. biol. trop ; 66(1): 136-148, Jan.-Mar. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-897660

RESUMEN

Resumen Los lagos tropicales de alta montaña presentan condiciones ambientales únicas donde los quironómidos tienen un papel importante en el funcionamiento del ecosistema. Las características de estos ambientes podrían favorecer el solapamiento de dietas y por ende una alta competencia interespecífica. En este estudio se describen los hábitos alimentarios de géneros de quironómidos, se identifica si los hábitos alimenticios son especializados o generalistas y se analiza el solapamiento en la dieta de los géneros. Entre abril y mayo de 2016 se colectaron larvas de Chironomidae de cuatro lagos del páramo de Chingaza. Se evaluó la dieta de larvas, mediante el análisis de contenido estomacal. Se ubicó cada género en gremios tróficos (carnívoro, detritívoro y alguívoro) y se estimó el solapamiento de las dietas entre los géneros mediante el índice de Pianka. Se colectó un total de 1 003 individuos y se identificaron nueve géneros. Las larvas consumieron principalmente materia orgánica particulada fina (MOPF), algas, fragmentos de macrófitas, macroinvertebrados y tejido animal. La MOPF fue la fuente principal de alimento de detritívoros. El análisis de dietas mostró una alta afinidad de cada género con un único gremio trófico y la mayor parte de los géneros son generalistas en el uso de recursos. En todos los lagos se observaron valores altos de solapamiento en la dieta entre los géneros y los gremios tróficos, principalmente entre los detritívoros. Los resultados sugieren que las larvas de Chironomidae presentan hábitos tróficos bien diferenciados, ocurriendo un moderado solapamiento de dietas entre géneros de detritívoros y carnívoros.


Abstract Tropical high mountain lakes show unique environmental conditions where chironomids play an important role in ecosystem functioning. The characteristics of these environments could favor diet overlap and therefore a high interspecific competition. This study described the dietary habits of chironomid genera, identified whether the dietary habits were specialized or generalist, and analyzed the diet overlap in the genera. Chironomidae larvae were collected from four lakes of the Chingaza paramo during the dry season, between April and May of 2 016. The feeding habits of larvae were evaluated by analyzing gut contents following standard methods. Each genus was assigned to trophic guilds (carnivore, detritivore and algivore) and the diet overlap was estimated using the Pianka's index. A total of 1 003 individuals were collected and nine genera were identified. Larvae consumed mainly fine particulate organic matter (FPOM), algae, macrophyte fragments, macroinvertebrates, and animal tissues. FPOM was the main feeding resource of detritivores. The analysis of diets showed a high affinity of each genus for a single trophic guild and most of the genera were generalist in the use of resources. For all lakes, high levels of diet overlap were observed among genera and trophic guilds, mainly among detritivores. Our results suggested that Chironomidae larvae of these lakes presented well differentiated trophic habits, and showed a moderate diet overlap within detritivores and carnivores. Rev. Biol. Trop. 66(1): 136-148. Epub 2018 March 01.

17.
Acta biol. colomb ; 22(1): 45-58, ene.-abr. 2017. ilus, tab
Artículo en Español | LILACS | ID: biblio-886042

RESUMEN

RESUMEN Los pequeños ríos de los Andes tropicales se han estudiado escasamente y poco se conoce sobre la composición, diversidad y estructura de sus comunidades de macrófitas. En esta investigación se estudiaron las comunidades de plantas acuáticas de 18 pequeños ríos andinos pertenecientes a las cuencas de los ríos La Vieja (Quindío) y Otún (Risaralda) en la ecorregión cafetera colombiana, una de las más afectadas por actividades antrópicas en el país. Se buscó evaluar el efecto del uso del suelo sobre la estructura de las comunidades de macrófitas. Para ello se seleccionaron ríos que nacen y discurren exclusivamente en cada uno de los usos del suelo dominantes en cada cuenca. El muestreo se realizó en dos épocas climáticas distintas del año 2006. La vegetación acuática encontrada en las dos cuencas (54 especies, pertenecientes a 25 familias) presentó riqueza y abundancia menores que las reportadas en otros sistemas acuáticos tropicales y estuvo dominada por especies con alta capacidad de adaptación a ambientes cambiantes o alterados. Se encontró que variables ambientales de los ríos asociadas con el tipo de uso del suelo, como la temperatura, la conductividad y el tipo de sustrato, fueron las que principalmente explicaron la estructura de las comunidades de macrófitas. Los ríos de zonas ganaderas, con dominancia de sustrato fino y valores más altos de temperatura y conductividad, presentaron mayor riqueza y abundancia de especies que los ríos de zonas con uso forestal, caracterizados por una alta cobertura arbórea del cauce, menor temperatura, baja concentración de nutrientes y predominancia de sustrato rocoso.


ABSTRACT Small streams of tropical Andes have been poorly studied. Therefore, there is little information about the structure, dynamics and function of their macrophyte communities. In this research, aquatic plant communities of 18 Andean streams of La Vieja (Quindío) and Otún (Risaralda) river basins were studied; those are some of the basins most affected by anthropic activities in the country. Streams were selected according to their association with the main land's uses of the region in both basins. The aim of the study was to evaluate the effect of land use on the structure of macrophyte communities. Streams running exclusively through each land use were selected. Sampling was done in two different climatic seasons in 2006. Vegetation found (54 species belonging to 25 families) was dominated by species with high capability of adaptation to changing and disturbed environments. Richness and abundance of macrophytes were lower than those reported in other tropical aquatic systems. Variables associated with land use, such as temperature, conductivity and type of substrate of the streams mainly explained the structure of the macrophyte communities: streams running on meat-cattle areas -with higher temperatures, conductivity and dominance of sandy-slimy substrates- had higher macrophyte species richness and abundance than streams of protected-forest areas, with higher coverage of riparian vegetation, lower temperatures and conductivity and rocky substrates.

18.
Med. UIS ; 27(3): 9-18, sep.-dic. 2014. ilus, tab
Artículo en Español | LILACS | ID: lil-743890

RESUMEN

Introducción: la anemia es un problema de salud pública a nivel mundial, según la Organización Mundial de la Salud afecta en todo el mundo a 1620 millones de personas. En América Latina y el Caribe el 31% de la población presenta problemas de anemia asociadas a dietas deficientes de hierro y relacionadas con malnutrición. Objetivo: evaluar los efectos terapéuticos del agua de mar isotónica microfiltrada al frío como terapia complementaria en modelos biológicos con anemia inducida experimentalmente por dietas pobres en proteínas, vitaminas y minerales, y por medicamentos. Materiales y métodos: se contó durante ocho semanas con 50 ratones cepas NMRI, de ambos géneros y en edad adulto-joven. Se dividieron en cuatro grupos experimentales de 10 ratones cada uno, incluyendo un grupo control. Fueron evaluados al inicio y final del experimento los parámetros hematológicos, pH salival, cobre y zinc. Al final del experimento fueron sacrificados por dislocación cervical y autopsiados para examinar bazo, hígado y riñón. Resultados: los modelos experimentales bajo ingesta de agua de mar con relación al grupo sin agua de mar, independiente del tipo de anemia inducida, evidenciaron diferencias estadísticamente significativas (p< 0,05) con restablecimiento de los parámetros hematológicos. El bazo se observó en tamaño y condiciones normales evidenciando restablecimiento del daño inmunológico ocasionado. Órganos como riñón e hígado no mostraron daños morfológicos. Conclusiones: el agua de mar isotónica resultó útil como terapia complementaria en los modelos experimentales, en casos de anemias causadas por dietas pobres en proteínas, vitaminas y minerales, y desencadenadas por medicamentos. MÉD.UIS. 2014;27(3):9-18.


Introduction: the anaemia is a major public health worldwide, according to the World Health Organization worldwide affects 1620 million people in Latin America and the Caribbean 31% of the population has problems anemia's associated with deficient diets iron and related malnutrition. Objective: evaluating those therapeutic effects of isotonic seawater microfiltered to cold as complementary therapy in biological models with experimentally induced anaemia by poor diets in protein, vitamins and minerals, and by medicaments. Materials and Methods: they counted for eight weeks with 50 NMRI mice of both genders, adult - young age. Were divided into four experimental groups of 10 mice each, including a control group. Evaluated to the beginning and end of the experiment were the hematological parameters, salivary pH, copper and zinc. At the end of the experiment they were sacrificed by cervical dislocation and autopsied stops examine spleen, liver and kidney. Results: the experimental models under seawater intake relative to the group without sea water, independent of the type of induced anaemia, showed statistically significant differences (p < 0.05) with restoration of hematological parameters. The spleen was observed in size and showing restoration of normal immune damage caused. Organs such as kidney and liver showed no morphological damage. Conclusions: isotonic seawater useful as complementary therapy in experimental models, in cases of anemia caused by diets low in protein, vitamins and minerals, and triggered by medicament. MÉD. UIS. 2014;27(3):9-18.


Asunto(s)
Animales , Ratones , Agua de Mar , Terapéutica , Anemia , Vitaminas , Zinc , Desnutrición , Usos Terapéuticos , Dieta , Hierro
19.
Univ. sci ; 18(1): 73-82, ene.-abr. 2013. ilus, tab
Artículo en Español | LILACS | ID: lil-677561

RESUMEN

Se comparó la abundancia relativa de Grundulus bogotensisentre dos cuencas y la dieta entre poblaciones de tres cuencas delaltiplano Cundiboyacense. Entre marzo y junio de 2006 se realizaronmuestreos en 10 localidades utilizando un equipo de electropesca. Laabundancia relativa de cada localidad se expresó como el número deindividuos capturado por hora en un tramo de 100m. Se utilizó untest de Kruskal-Wallis para determinar diferencias significativas en laabundancia relativa entre cuencas. Para cuantificar la dieta se utilizóel método volumétrico y para determinar el grado de similaridadentre cuencas se recurrió a tres análisis multivariados: análisis deescalonamiento multidimensional no métrico (NMDS), análisisde similaridad (ANOSIM) y análisis de porcentaje de similaridad(SIMPER). Se capturaron en total 675 individuos, empleando 600minutos de esfuerzo de captura. La abundancia de la especie en lacuenca del río Bogotá fue significativamente menor respecto a ladel río Suárez. La composición de la dieta y volumen de ítems entrecuencas fue similar. El material consumido fue de origen autóctonoy los ítems más importantes fueron los insectos inmaduros y losmicrocrustáceos. La abundancia relativa de las poblaciones de G.bogotensis en la cuenca del río Bogotá fue menor que en la cuenca delrío Suárez. La cuenca del río Suárez probablemente soporta la mayorabundancia de la especie en todo su rango de distribución y los datossugieren condiciones favorables para la sobrevivencia de la Guapuchaen el lago de Tota. El análisis de la dieta indicó una similaridad mayoral 60% en la utilización del recurso alimentar en las tres cuencas...


To compare the relativeabundance of Grundulus bogotensis in two river basinsand the diet of the populations of three basins in theCundiboyacense plateau, we sampled 10 localities usingelectrofishing equipment between March and June 2006.The relative abundance in each locality was expressedas the number of fish caught per hour on a 100mstretch; any significant differences in relative abundanceamong basins were identified via a Kruskal-Wallis test.To quantify the diet, we used the volumetric method.Similarities between the basins were determined usingthree multivariate analyzes: nonmetric multidimensionalscaling, analysis of similarity and similarity percentages.In the end, we collected a total of 675 individuals during600 minutes of capture effort. The abundance of thisspecies in the Bogotá river basin was significantly lowercompared to that of the Suárez basin. The dietarycomposition, of autochthonous origin, primarilyimmature insects and microcrustaceans and the volumeof items proved similar between the basins. In conclusion,the dietary analysis indicated a similarity exceeding 60%in the feed resource use for the three basins. The relativeabundance of populations of G. bogotensis in the Bogotáriver basin was lower than in the Suárez river basin, thelatter having, possibly, the greatest abundance of thisspecies throughout its range. The data suggests the mostfavorable conditions for the survival of the species inLake Tota...


Comparar a abundância relativa de Grundulus bogotensisentre duas bacias e a dieta entre populações de três bacias do planaltoCundiboyacense. Entre março e junho de 2006 foram realizadascoletas em 10 localidades utilizando equipamento de pesca elétrica. Aabundância relativa da espécie em cada localidade foi expressa comoo número de indivíduos capturados por hora em um trecho de 100mde extensão. Foi utilizado o teste de Kruskal-Wallis para determinardiferenças significativas na abundância relativa entre as bacias.Para quantificar a dieta foi utilizado o método volumétrico e paradeterminar o grau de similaridade entre bacias foram utilizadas trêsanálises multivariadas: análise de escalonamento multidimensionalnão métrico (NMDS), análise de similaridade (ANOSIM) e análise deporcentagem de similaridade (SIMPER). No total foram capturados675 indivíduos, empregando 600 minutos de esforço de captura. Aabundância desta espécie na bacia do rio Bogotá foi significativamentemenor que na bacia do rio Suárez. A composição da dieta e volumedos itens de alimento entre bacias foram similares. Os recursosconsumidos foram de origem autóctone e os itens mais abundantesforam insetos imaturos e microcrustáceos. A abundância relativa daspopulações de G bogotensis na bacia do rio Bogotá foi menor do quena bacia do rio Suárez. A bacia do rio Suárez provavelmente suporta amaior abundância da espécie em toda a área de distribuição e os dadossugerem condições favoráveis para a sobrevivência da Guapucha noLago de Tota. A análise da dieta indicou uma similaridade maior a60% na utilização do recurso alimentar nas três bacias...


Asunto(s)
Análisis de la Situación , Cuencas/análisis , Especies en Peligro de Extinción/estadística & datos numéricos , Colombia
20.
Rev. Inst. Nac. Hig ; 43(1): 25-34, jun. 2012. graf, tab
Artículo en Español | LILACS, LIVECS | ID: lil-664631

RESUMEN

La investigación tuvo como propósito obtener la antraquinona contenida en el exudado de Aloe vera (L.) Burm.f. (zábila) mediante el método de cristalización y su identificación mediante la técnica de espectrofotometría de radiación infrarroja. La muestra la conformaron 18 plantas de zábila, recolectadas al oeste de la ciudad Santa Ana de Coro, estado Falcón. Se utilizaron tres métodos para la obtención de antraquinona a partir del exudado de zábila. En el método A, la antraquinona se obtuvo por descenso de la temperatura; en el método B, las muestras fueron liofilizadas y luego se disminuyó la temperatura; y en el método C, la antraquinona se obtuvo mediante un modificador de matriz. Con el método A se obtuvo un rendimiento de antraquinona de 7,65 ± 4,62% p/p; con el método B 5,74 ± 3,25 % p/p y con el método C 25,93 ± 1,49% p/p. El mayor rendimiento de antraquinona se obtuvo con el método de precipitación mediante modificador de matriz.


The purpose of this wok was obtain the anthraquinone from Aloe vera exudate applying method by crystallization and identifies it through spectrophotometric infrared and ultraviolet- visible techniques. The sample were 18 plants of Aloe vera, recollected at west of Coro city, Falcón state. It was used 3 methods to obtain anthraquinone from Aloe vera exudate. In the method A, anthraquinone was obtained by temperature descend; in the method B, the samples were lyophilized and temperature descends; and in the method C, anthraquinone was obtained by matrix modifier. With the method A it was obtained 7,65 ± 4,62% w/w of anthraquinone; with method B 5,74 ± 3,25 % w/w and with the method C 25,93 ± 1,49% w/w. The method with the best efficiency to obtain anthraquinone was the method C.


Asunto(s)
Humanos , Masculino , Femenino , Plantas Medicinales , Antraquinonas/química , Aloe/inmunología , Medicina/métodos , Farmacología , Salud Pública , Aloe/fisiología
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