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1.
Zootaxa ; 5128(4): 503-537, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-36101153

RESUMEN

The species of Chloeia Savigny in Lamarck, 1818 include some of the most colorful amphinomid annelids in tropical seas. Their pigmentation patterns can be diagnostic but because some pigments may fade after ethanol preservation, they have been disregarded as useful taxonomic characters. In this contribution we revise the tropical American species of Chloeia, and we confirm stability of pigmentation patterns, the presence of cirriform branchiae along a few anterior chaetigers, and emphasize the size of eyes and of ventral cirri as diagnostic characters. Five species are redescribed and two ones are newly described; the redescribed species are C. entypa Chamberlin, 1919 from Western Mexico, C. euglochis Ehlers, 1887 from the Grand Caribbean (reinstated), C. pinnata Moore, 1911 from Southern California (extended southwards in Western Mexico), C. pseudeuglochis Augener, 1922 from Pacific Costa Rica (includes several records for a colorful shallow water species in the Eastern Pacific), and C. viridis Schmarda, 1861 from the Grand Caribbean, which is restricted to specimens having a single, dorsal longitudinal T-shaped band. New species are Chloeia nuriae sp. n. from the Gulf of California, and C. paulayi sp. n. from the Gulf of Mexico . Two other species previously recorded for the region, C. conspicua Horst, 1910 and C. flava (Pallas, 1766) are briefly characterized in order to avoid future misidentifications. Further, C. candida Kinberg, 1857 from the Virgin Islands, is regarded as indeterminable. A key to identify tropical American species of Chloeia is also included.


Asunto(s)
Poliquetos , Animales , Océanos y Mares , Pigmentación
2.
J Environ Sci Health B ; 57(10): 775-785, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36048159

RESUMEN

Glyphosate [N-(phosphonomethyl)glycine] is one of the most popular herbicides worldwide. Globally, the use of glyphosate is increasing, and its residues have been found in drinking water and food products. The data regarding the possible toxic effects of this herbicide are controversial. Therefore, the aim of this study was to evaluate the effects of glyphosate at environmental concentrations in zebrafish (Danio rerio) embryos. Embryos were exposed to 0, 1, 100, and 1,000 µg/L glyphosate for 96 h, and mortality, heart rate, and hatching rate were evaluated. After the experiment, RNA was extracted from the embryos for transcriptional analysis. No mortality was recorded, and exposure to 100 µg/L and 1,000 µg/L of glyphosate resulted in lower heart rates at 48 h. In addition, RNA-seq analysis revealed that glyphosate exposure induced subtle changes in gene transcription profiles. We found 30 differentially expressed genes; however, the highest glyphosate concentration (1,000 µg/L) induced the greatest number of differentially expressed genes involved in oocyte maturation, metabolic processes, histone deacetylation, and nervous system development.


Asunto(s)
Agua Potable , Herbicidas , Animales , Embrión no Mamífero , Glicina/análogos & derivados , Herbicidas/farmacología , Histonas/metabolismo , Histonas/farmacología , ARN/metabolismo , ARN/farmacología , Transcriptoma , Pez Cebra/genética , Pez Cebra/metabolismo , Glifosato
3.
Environ Sci Pollut Res Int ; 29(56): 85172-85184, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35794329

RESUMEN

Glyphosate levels and the transfer of glyphosate across trophic levels have rarely been studied in zooplankton. The food preferences of zebrafish during the first-feeding stage (which is critical for the survival of organisms), were analyzed because of the requirement for live food. Larval survival begins to be affected when glyphosate intake exceeds 0.3666 µg/larvae/day, in the case that only the food is contaminated; if the medium is also contaminated, the effects on survival start from 0.2456 µg/larvae/day. It was shown that glyphosate was more likely to be incorporated through the medium than through the food (zooplankton), which supports the results of previous studies that have ruled out the potential for biomagnification. The bioconcentration factor (BCF) of glyphosate was determined using an ELISA tests specific to measure glyphosate in the fish D. rerio, the rotifers Brachionus calyciflorus and Lecane papuana, and the cladoceran Ceriodaphnia dubia. The experimental design consisted in exposing seven zebrafish adults per replica (four replicates) in three treatments 1, 5, and 10 mg/L of glyphosate for 96 h to obtain bioconcentration factors in the gills, liver, and muscle. These concentrations were selected as potential glyphosate concentrations right after application as double highest reported concentration. Glyphosate levels in zooplankton can represent up to 6.26% of the total weight of rotifers (BFC = 60.35) and in zebrafish adult organs were less than 8 µg/mg of tissue (BCF values < 6). Although glyphosate does not biomagnify, our results suggest that glyphosate affected the dynamics between zooplankton and zebrafish larvae, diminishing survival and feeding rates, given that zooplankton species bioconcentrate glyphosate in large quantities. The BCF values found in this contribution are higher than expected. Glyphosate exposure affected energy metabolism and feeding behavior of zebrafish larvae, which presented high mortality rates at environmentally relevant concentrations.


Asunto(s)
Rotíferos , Contaminantes Químicos del Agua , Animales , Pez Cebra/fisiología , Glicina/toxicidad , Rotíferos/metabolismo , Larva/metabolismo , Zooplancton/metabolismo , Conducta Alimentaria , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/metabolismo , Glifosato
4.
Front Cell Dev Biol ; 10: 832982, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281093

RESUMEN

Zebrafish (Danio rerio) is a well-established vertebrate model in ecotoxicology research that responds to a wide range of xenobiotics such as pesticides, drugs, and endocrine-disrupting compounds. The epigenome can interact with the environment and transform internal and/or external signals into phenotypic responses through changes in gene transcription. Environmental exposures can also generate epigenetic variations in offspring even by indirect exposure. In this review, we address the advantages of using zebrafish as an experimental animal model to study transgenerational epigenetic processes upon exposure to xenobiotics. We focused mostly on DNA methylation, although studies on post-translational modifications of histones, and non-coding RNAs related to xenobiotic exposure in zebrafish are also discussed. A revision of the methods used to study epigenetic changes in zebrafish revealed the relevance and reproducibility for epigenetics-related research. PubMed and Google Scholar databases were consulted for original research articles published from 2013 to date, by using six keywords: zebrafish, epigenetics, exposure, parental, transgenerational, and F2. From 499 articles identified, 92 were considered, of which 14 were selected as included F2 and epigenetic mechanisms. Current knowledge regarding the effect of xenobiotics on DNA methylation, histone modifications, and changes in non-coding RNAs expressed in F2 is summarized, along with key experimental design considerations to characterize transgenerational effects.

5.
Zookeys ; 1080: 165-208, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35068967

RESUMEN

A new species of Cletocamptus closely related to C.helobius was found in sediment samples taken from a polluted estuarine system in north-western Mexico. The genus Cletocamptus was relegated to species incertae sedis in 1986, and this finding prompted us to evaluate the current taxonomic position of the genus within the Canthocamptidae. The latter has been subdivided in several, seemingly unnatural subfamilies in the past to better understand the relationships between its constituent taxa. In this study we propose a new subfamily, the Cletocamptinaesubfam. nov. for Amphibiperita, Cletocamptus, and Cletocamptoides gen. nov., defined by the synapomorphic subdistal ventral spinules on the rostrum. The genus Cletocamptoides gen. nov. is proposed for C.helobius, C.merbokensis, and C.biushelo sp. nov., and is supported by the 'cletodid' shape of the body and the reduced one-segmented endopod of the fourth swimming leg. Cletocamptus includes all the other species with long slender spinules on the posterior margin of prosomites and with the sexually modified inner spine on the second endopodal segment of the second swimming leg in the males. Amphibiperita retained the primitive female fifth leg with exopod and baseoendopod separated, and the primitive prehensile endopod of the first leg, but is defined by the loss of the antennary exopod. Other (syn)apomorphies are given, and the evolution of the mandibular palp is briefly discussed. Additionally, a diagnosis for the new subfamily, Cletocamptinae subfam. nov., an amended narrower diagnosis for Cletocamptus, the diagnosis for Cletocamptoides gen. nov., and a phylogenetic analysis supporting the proposal of these new taxa, are given.

6.
Bull Environ Contam Toxicol ; 108(4): 646-651, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34807277

RESUMEN

Glyphosate is the most used herbicide in the world. Unfortunately, contamination of water bodies by this herbicide has been reported. A severe concern has been triggered given its detrimental impact on the environment and wildlife. The American horseshoe crab (Limulus polyphemus) is a benthic arthropod that inhabits the Yucatan Peninsula in Southeast Mexico. This study evaluates the glyphosate concentration in 34 recently dead specimens of L. polyphemus from four localities of the Ria Lagartos Biosphere Reserve in Yucatan, Mexico. The analysis was carried out using High-Performance Liquid Chromatography coupled with a Triple Quadrupole Mass Spectrometer. All the samples showed residues of glyphosate in the range from 0.08 to 2.38 ng g-1. These records constitute the first evidence of glyphosate bioaccumulation in this species. Although the scope might be limited, the results demonstrate a potentially prejudicial exposition of the marine biota to glyphosate-based herbicides, given its use in the region.


Asunto(s)
Herbicidas , Cangrejos Herradura , Animales , Glicina/análogos & derivados , Glicina/análisis , Herbicidas/análisis , México , Glifosato
7.
Biodivers Data J ; 10: e87666, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761672

RESUMEN

This is the first record of two non-native terrestrial slug species from Sinaloa, Mexico. Deroceraslaeve and Sarasinulaplebeia were collected between 2019 and 2022 in Concordia and Mazatlan Municipalities (north-western Mexico). The external morphology and anatomic features of the dissected specimens coincide with the descriptions of each species, whose identities were also confirmed by their partial COI sequences. The ample occurrence of S.plebeia suggests that this species has an established population, while D.laeve was found as isolated individuals, likely associated with plant nurseries.

8.
Altern Lab Anim ; 49(4): 147-156, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34814757

RESUMEN

Two cell lines derived from the brain and heart of a Pacific white snook specimen (Centropomus viridis) were developed and evaluated in terms of their responsiveness to glyphosate-induced cytotoxicity. The cells were grown in Leibovitz-15 (L-15) medium supplemented with 10% fetal bovine serum (FBS) and were passaged 36 times. Growth was tested at different concentrations of FBS (5, 10 and 20%) at 27°C. The cell lines were cryopreserved at different passages and were successfully thawed, with a survival rate greater than 80% without detectable contamination. At passage 36, the cells were used to assess the deleterious effects of glyphosate, and cell proliferation was measured by direct counting and with the MTT assay. Similar LC50 values were obtained with both methods. Although the principles behind these two assessment methods differ, our results show that both are suitable for evaluating glyphosate toxicity. In addition, heart- and brain-derived cells showed similar sensitivity, suggesting that the same mode of action might be responsible for the toxicity of glyphosate at the cellular level. The newly developed Pacific white snook brain and heart cell lines could be useful to investigate cellular and molecular mechanisms of toxicity, satisfying the need to reduce the use of animals in experiments. Glyphosate-related toxicological data obtained in the present study will allow us to continue investigating the effects of this herbicide directly on brain and heart fish cells since similar studies have only been carried out on either live organisms or on human cell lines such as neuroblastoma, which are immortalised by oncogenes or similar.


Asunto(s)
Peces , Xenobióticos , Animales , Encéfalo , Línea Celular , Criopreservación , Humanos , Xenobióticos/toxicidad
9.
Environ Toxicol Pharmacol ; 87: 103700, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34237469

RESUMEN

Glyphosate [N-(phosphonomethyl)glycine] is the active ingredient in widely used broad-spectrum herbicides. Even though the toxicity mechanism of this herbicide in vertebrates is poorly understood, evidence suggests that glyphosate is an endocrine disruptor capable of producing morphological anomalies as well as cardiotoxic and neurotoxic effects. We used the zebrafish model to assess the effects of early life glyphosate exposure on the development of cartilage and bone tissues and organismal responses. We found functional alterations, including a reduction in the cardiac rate, significant changes in the spontaneous tail movement pattern, and defects in craniofacial development. These effects were concomitant with alterations in the level of the estrogen receptor alpha osteopontin and bone sialoprotein. We also found that embryos exposed to glyphosate presented spine deformities as adults. These developmental alterations are likely induced by changes in protein levels related to bone and cartilage formation.


Asunto(s)
Huesos/efectos de los fármacos , Anomalías Craneofaciales/inducido químicamente , Glicina/análogos & derivados , Herbicidas/toxicidad , Teratógenos/toxicidad , Animales , Huesos/anomalías , Anomalías Craneofaciales/metabolismo , Anomalías Craneofaciales/veterinaria , Embrión no Mamífero/anomalías , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Proteínas de Peces/metabolismo , Glicina/toxicidad , Frecuencia Cardíaca/efectos de los fármacos , Locomoción/efectos de los fármacos , Masculino , Osteopontina/metabolismo , Sialoglicoproteínas/metabolismo , Pez Cebra/anomalías , Pez Cebra/metabolismo , Glifosato
10.
Gene ; 783: 145577, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33737123

RESUMEN

Transcriptional response regulators (TRR) are the most abundant signal transducers in prokaryotic systems that mediate intracellular changes in response to environmental signals. They are involved in a wide range of biological processes that allow bacteria to persist in particular habitats. There is strong evidence that the bacterial habitat and their lifestyle influence the size of their TRR genetic repertoire. Therefore, it would be expected that the evolution of bacterial genomes could be linked to natural selection processes. To test this hypothesis, we explored the evolutionary dynamics of TRR genes of the widely studied Harveyi clade of the genus Vibrio at the molecular and genomic levels. Our results suggest that the TRR genetic repertoire of the species belonging to the Harveyi clade is a product of genomic reduction and expansion. The gene loss and gains that drive their genomic reduction and expansion could be attributed to natural selection and random genetic drift. It seems that natural selection acts to maintain the ancestral state of core TRR genes (shared by all species) by purifying processes and could be driving the loss of some accessory (found in certain species) genes through the diversification of sequences. The neutrality observed in gene gain could be attributed to spontaneous events as horizontal gene transfer driven by stochastic events as occurs in random genetic drift.


Asunto(s)
Evolución Molecular , Genes Bacterianos , Genes Reguladores , Vibrio/genética , Regulación Bacteriana de la Expresión Génica , Transferencia de Gen Horizontal , Genoma Bacteriano
11.
Heliyon ; 7(1): e06027, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33532646

RESUMEN

Glyphosate, the most commonly used pesticide worldwide, blocks aromatic amino acid biosynthetic pathways and inhibits growth in plants. Although the specific mode of action of glyphosate in animals remains unclear, adverse effects during embryonic development have been reported, including epiboly delays, morphological alterations, and changes in central nervous system development and cardiogenesis. In this study, we suggest a possible toxicity mechanism for this herbicide related to changes in microtubule stability, which could alter the distribution and dynamics of cytoskeleton components. Using zebrafish embryos to evaluate in vivo effects of glyphosate exposure (5, 10, and 50 µg/ml), we found significant reductions in the levels of acetylated α-tubulin (50 µg/ml) and in the polymeric tubulin percentage in zebrafish embryos that had been exposed to 10 and 50 µg/ml glyphosate, without any changes in either the expression patterns of α-tubulin or the stability of actin filaments. These results indicate that high concentrations of glyphosate were associated with reduced levels of acetylated α-tubulin and altered microtubule stability, which may explain some of the neurotoxic and cardiotoxic effects that have been attributed to this herbicide.

12.
Biodivers Data J ; 8: e57572, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33013175

RESUMEN

BACKGROUND: The islands and islets of Bahía de Chamela, in the Eastern Tropical Pacific, were declared as the first marine sanctuary in Mexico and has been protected since 2002. Their marine biodiversity has been documented in a series of papers in the last decade, but only three species of polychaete worms have been reported. NEW INFORMATION: Sixteen species of sedentary polychaete worms belonging to the families Maldanidae, Oweniidae, Sabellariidae, Sabellidae and Serpulidae are reported to the Bahía de Chamela Islands Sanctuary, 15 of these species constituting the first records in the area. Isocirrus tropicus (Monro, 1928) (Monro 1928) and Notaulax californica (Treadwell, 1906) (Treadwell 1906) constitute new records to Mexico; Idanthyrsus mexicanus Kirtley, 1904 (Kirtley 1994) is first recorded since its description and one species of bamboo worm (Maldanidae) is described as new to science. The new species belongs to the genus Clymenura Verril, 1900 (Verrill 1900) and its characterised by the presence of a glandular shield on chaetiger 8; a cephalic plaque oval with smooth margins and a rounded palpode; nuchal organs straight, parallel, almost full length of plaque; manubriavicular uncini present from chaetiger 1 with 3-4 teeth above the main fang without hairs or bristles; two pre-anal achaetous segments with tori; an anal funnel with alternating triangular cirri, being the longest that are located mid-ventrally.

13.
Biomarkers ; 24(2): 141-152, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30231650

RESUMEN

CONTEXT: Fiddler crabs are important to the ecology of estuarine systems around the world, however, few studies have incorporated them as bioindicators. Urias estuary represents one of the most urbanized lagoons in the Gulf of California region and received discharges from different sources: shrimp farm, thermoelectric plant, fish processing plants, and untreated domestic and sewage wastes. OBJECTIVE: Assess the effects on anthropogenic contamination on female fiddler crabs reproduction, survival and genetic stability. METHODS: Exposition of wild crabs from a less impacted (reference) site to naturally contaminated sediments on under controlled laboratory conditions. Reproductive parameters, levels of DNA damage and mortality rates were measured, together with chemical analyses of sediments. RESULTS: The most contaminated sediments corresponded to the site where fish processing plants were located and the integrated biomarker response analysis revealed that the most adverse effects were produced by exposure to sediments from this site; these crabs showed higher mortality (67%) and poorer ovarian development than those crabs exposed to sediments from other sites. CONCLUSIONS: Female crabs under pollution stress are able to trade-off reproduction for survival, and surviving animals were able to restore genetic stability possibly by activating DNA repair mechanisms. Multiple biomarker approach discriminates different coastal contamination scenarios.


Asunto(s)
Biomarcadores/química , Braquiuros/química , Monitoreo del Ambiente , Contaminantes Químicos del Agua/aislamiento & purificación , Animales , Femenino , Humanos , Contaminantes Químicos del Agua/metabolismo
14.
Appl Microbiol Biotechnol ; 101(3): 1189-1201, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27743044

RESUMEN

The use of synthetic dyes for laccase induction in vivo has been scarcely explored. We characterized the effect of adding different synthetic dyes to liquid cultures of Pycnoporus sanguineus on laccase production. We found that carminic acid (CA) can induce 722 % and alizarin yellow 317 % more laccase than control does, and they promoted better fungal biomass development in liquid cultures. Aniline blue and crystal violet did not show such positive effect. CA and alizarin yellow were degraded up to 95 % during P. sanguineus culturing (12 days). With this basis, CA was selected as the best inducer and used to evaluate the induction of laccase on solid-state fermentation (SSF), using sugarcane bagasse (SCB) as substrate, in an attempt to reach selective delignification. We found that laccase induction occurred in SSF, and a slight inhibition of cellulase production was observed when CA was added to the substrate; also, a transformation of SCB under SSF was followed by the 13C cross polarization magic angle spinning (CPMAS) solid-state nuclear magnetic resonance (NMR). Results showed that P. sanguineus can selectively delignify SCB, decreasing aromatic C compounds by 32.67 % in 16 days; O-alkyl C region (polysaccharides) was degraded less than 2 %; delignification values were not correlated with laccase activities. Cellulose-crystallinity index was increased by 27.24 % in absence of CA and 15.94 % when 0.01 mM of CA was added to SCB; this dye also inhibits the production of fungal biomass in SSF (measured as alkyl C gain). We conclude that CA is a good inducer of laccase in liquid media, and that P. sanguineus is a fungus with high potential for biomass delignification.


Asunto(s)
Celulosa/metabolismo , Colorantes/farmacología , Lacasa/biosíntesis , Lignina/metabolismo , Pycnoporus/efectos de los fármacos , Pycnoporus/enzimología , Compuestos Azo/metabolismo , Compuestos Azo/farmacología , Biomasa , Carmín/metabolismo , Carmín/farmacología , Colorantes/metabolismo , Medios de Cultivo/química , Inducción Enzimática , Fermentación , Lacasa/metabolismo , Pycnoporus/metabolismo
15.
Folia Microbiol (Praha) ; 61(2): 137-42, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26233233

RESUMEN

The aim was to determine which specific regions of the visible light spectrum were responsible for the induction or inhibition of laccase in Pycnoporus sanguineus. Cultures were exposed to various bandwidth lights: blue (460 nm), green (525 nm), white (a combination of 460 and 560 nm), red (660 nm), and darkness. The results indicate that short wavelengths strongly inhibit the production of laccase: green (3.76 ± 1.12 U/L), blue (1.94 ± 0.36 U/L), and white (1.05 ± 0.21 U/L) in proportions of 85.8, 92.6, and 96.0%, respectively; whereas long wavelengths inhibit laccase production only partially i.e., red light (14.05 ± 4.79 U/L) in a proportion of 46.8%. Maximum activity was induced in absence of visible light (30 °C, darkness), i.e., 30.76 ± 4.0 U/L. It is concluded that the production of laccase in P. sanguineus responds to light stimuli [measured as wavelengths and lx] and that it does so inversely. This can be explained as an ecological mechanism of environmental recognition, given that P. sanguineus develops inside lignocellulose structures in conditions of darkness. The presence of short wavelength light (460-510 nm) would indicate that the organism finds itself in an external environment, unprovided of lignin, and that it is therefore unnecessary to secrete laccase. This possible new regulation in the laccase production in P. sanguineus has important biotechnological implications, for it would be possible to control the production of laccase using light stimuli.


Asunto(s)
Proteínas Fúngicas/antagonistas & inhibidores , Lacasa/antagonistas & inhibidores , Pycnoporus/enzimología , Pycnoporus/efectos de la radiación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Lacasa/genética , Lacasa/metabolismo , Luz , Pycnoporus/genética
16.
Salud UNINORTE ; 30(3): 392-404, sep.-dic. 2014. ilus, tab
Artículo en Español | LILACS-Express | LILACS | ID: lil-747695

RESUMEN

Objetivo: Identificar los conocimientos y prácticas sexuales en la población de adolescentes de los grados 8 a 11 de una institución educativa de la ciudad de Manizales (Caldas, Colombia). Materiales y métodos: Estudio de corte transversal; la población estuvo conformada por 170 adolescentes de 14 a 21 años, matriculados en los grados 8 a 11 de Básica Secundaria de una institución educativa de la ciudad de Manizales, de estratos medio y bajo. Se realizó por el método de encuesta. Se tomaron diferentes variables sobre conocimientos sexuales, prácticas sexuales y factores de riesgo para embarazo y enfermedades de transmisión sexual. Resultados: El promedio de edad fue de 16,31 años, de género masculino en un 56,5 %. Presentaron un promedio de 2,9 (sobre 5) de conocimientos en educación sexual, 1,8 en métodos anticonceptivos, 2,4 en embarazo, 3,5 en enfermedades de transmisión sexual, para un promedio total de 2,7. El 91,8 % ha tenido experiencias sexuales, 70,1 % con penetración; 46,6 % no emplea métodos anticonceptivos; 5 % de las mujeres manifestó que había tenido embarazos; 4,2 % dijo que no ha tenido enfermedades de transmisión sexual. El bajo puntaje de conocimientos correlaciona significativamente con incomodidad en el empleo de métodos anticonceptivos (p=0.018), desconocimiento de para qué se emplean (p=0.019), no empleo de ellos (p=0,007). Conclusiones: Debido al bajo conocimiento en temas de sexualidad y la intensa práctica sexual, esta población se convierte en población de alta riesgo para presencia de embarazos no deseados, de abortos inducidos y de enfermedades de transmisión sexual.


Objective: To identify the knowledge and the sexual practices in teen agers of 8 to 11 grade of two schools Manizales city (Caldas, Colombia). Methodology: This is a transversal retrospective study with survey application; the population were 170 teen agers between 14 and 21 years of age, who are studying from 8 to11 grades of high school of two schools Manizales city, who are in medium and low stratus. The study was done with a survey. Was use different variables about the sexual knowledge, sexual practices and risk factors about pregnancy and sexually transmitted diseases. Results: The standard of age was of 16,31 ages, the masculine genre a 56.5 %.Was an average of 2,9 (over 5) of knowledge in sexual education, 1,8 in contraceptive methods, 2,4 in pregnancy, 3,5 in sexually transmitted diseases, for an average of 2,7.The 91,8 % has had sexual experiences, 70,1 % with penetration; 46.6% do not use contraceptive methods; 5 % of the women said has had pregnancies; 4,2% said has had sexually transmitted diseases. The low score of knowledge have a significantly coincidence with the discomfort with the use of contraceptive methods (p=0.018), ignorance of which is used for (p=0.019), do not use of it. Conclusions: According to the low knowledge in sexual topics and the intense sexual practice, this population is a high risk population to have unwanted pregnancies, induced abortions and sexually transmitted diseases.

17.
PLoS One ; 9(11): e113303, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25411842

RESUMEN

Coleopterans are the most diverse insect order described to date. These organisms have acquired an array of survival mechanisms through their evolution, including highly efficient digestive systems. Therefore, the coleopteran intestinal microbiota constitutes an important source of novel plant cell wall-degrading enzymes with potential biotechnological applications. We isolated and described the cultivable fungi, actinomycetes and aerobic eubacteria associated with the gut of larvae and adults from six different beetle families colonizing decomposing logs in protected Costa Rican ecosystems. We obtained 611 isolates and performed phylogenetic analyses using the ITS region (fungi) and 16S rDNA (bacteria). The majority of fungal isolates belonged to the order Hypocreales (26% of 169 total), while the majority of actinomycetes belonged to the genus Streptomyces (86% of 241 total). Finally, we isolated 201 bacteria spanning 19 different families belonging into four phyla: Firmicutes, α, ß and γ-proteobacteria. Subsequently, we focused on microbes isolated from Passalid beetles to test their ability to degrade plant cell wall polymers. Highest scores in these assays were achieved by a fungal isolate (Anthostomella sp.), two Streptomyces and one Bacillus bacterial isolates. Our study demonstrates that Costa Rican beetles harbor several types of cultivable microbes, some of which may be involved in symbiotic relationships that enable the insect to digest complex polymers such as lignocellulose.


Asunto(s)
Actinobacteria/clasificación , Bacterias Aerobias/clasificación , Pared Celular/metabolismo , Escarabajos/microbiología , Hongos/clasificación , Células Vegetales/metabolismo , Actinobacteria/enzimología , Actinobacteria/aislamiento & purificación , Animales , Bacterias Aerobias/enzimología , Bacterias Aerobias/aislamiento & purificación , Escarabajos/anatomía & histología , Escarabajos/clasificación , Costa Rica , ADN Bacteriano/análisis , ADN de Hongos/análisis , Hongos/enzimología , Hongos/aislamiento & purificación , Intestinos/microbiología , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
18.
Zookeys ; (223): 69-84, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23459182

RESUMEN

The species of the genus Notopygos Grube, 1855 are characterized by an ovate body, a prominent caruncle with three lobes, dendritic branchiae, and double dorsal cirri. Twenty-two species belonging to Notopygos have been described, mostly from the Indo-Pacific region. In America, few species are frequently recorded: Notopygos crinita Grube, 1855 from St. Helena Island (Atlantic) and Notopygos ornata Grube and Ørsted in Grube 1857 from Costa Rica (Pacific). Notopygos crinita is a widely distributed species in the Western Atlantic with additional reports in the Mediterranean Sea (as a questionable alien species) and in the Pacific Ocean. However, only the genus features have been considered, consequently some records could be misidentifications. During a revision of materials from collections and the barcode project, 'Mexican Barcode of Life, MEXBOL', we found specimens of Notopygos megalops and an undescribed species from reef zones in the Caribbean; the former had been considered a junior synonym of Notopygos crinita. Herein, Notopygos megalops is reestablished and Notopygos caribeasp. n. is described. A morphological and DNA barcode approach was used to explain the records of Notopygos ornata in the Atlantic and to show the differences with the new species, since both species share features such as complex pigmentation patterns, and circular projections in the median lobe of the caruncle.

19.
Rev. salud pública ; 13(5): 772-777, oct. 2011. ilus, tab
Artículo en Español | LILACS | ID: lil-625642

RESUMEN

Para el estudio de la dinámica del VIH-SIDA en la ciudad de Cali, se uso el clásico modelo SIR para la transmisión de enfermedades infecciosas, donde la población total es dividida en Susceptibles, Infectados y Removidos, con los supuestos de que la transmisión sexual es el único medio de contagio y los individuos no se recuperan y mueren. Basándose en la información suministrada por la Secretaria Municipal de Salud de Santiago de Cali, DANE y Planeación Municipal, se estimaron los parámetros del modelo y del número reproductivo básico. Se realizaron simulaciones de algunos escenarios con el propósito de establecer tendencias a largo plazo de la enfermedad. Se estimaron los puntos de equilibrio del sistema y se analizaron las condiciones de estabilidad, encontrándose que actualmente el sistema posee dos puntos de equilibrio: E1: Libre de la enfermedad, de naturaleza inestable; E2: Endémico, de naturaleza asintóticamente estable. Tomando como condiciones iniciales la información del año 2008, se observo que la enfermedad tiende al equilibrio endémico después de 100 años. A través de simulaciones se logro establecer que al reducir la probabilidad de contagio entre susceptibles e infectados, la enfermedad tiende al equilibrio endémico de forma más lenta y se logra disminuir el número máximo de infectados y removidos.


The classical Kermack-Mckendric SIR model for infectious disease transmission was used for studying the dynamics of HIV-AIDS in the city of Cali; individuals were classified as being susceptible, infected or recovered (SIR) on the assumption that sexual transmission would be the only means of transmission and that individuals would not recover or die. The model's parameters and basic reproductive numbers were estimated using information supplied by the Santiago de Cali Municipal Secretariat of Health, the Colombian Statistics Bureau (DANE) and the Municipal Planning department. Some scenarios were simulated to establish long-term disease trends. The system's equilibrium points were estimated and stability conditions analyzed finding that the current system had two equilibrium points: unstable, disease-free (E1) and stable, endemically asymptotic (E2). Taking information from 2008 as initial conditions, it was observed that the disease would tend towards equilibrium after a 100 year endemic. Simulations suggested that the disease would tend towards endemic equilibrium more slowly by reducing the probability of contact between susceptible and infected individuals and that the maximum number of infected and recovered could also become reduced.


Asunto(s)
Femenino , Humanos , Masculino , Infecciones por VIH/epidemiología , Modelos Teóricos , Colombia/epidemiología , Simulación por Computador , Resistencia a la Enfermedad , Susceptibilidad a Enfermedades , Infecciones por VIH/transmisión , Morbilidad/tendencias , Probabilidad , Factores de Riesgo , Conducta Sexual , Población Urbana
20.
Ecol Appl ; 21(1): 9-21, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21516884

RESUMEN

Predictive theory on how plant diversity promotes herbivore suppression through movement patterns, host associations, and predation promises a potential alternative to pesticide-intensive monoculture crop production. We used meta-analysis on 552 experiments in 45 articles published over the last 10 years to test if plant diversification schemes reduce herbivores and/or increase the natural enemies of herbivores as predicted by associational resistance hypotheses, the enemies hypothesis, and attraction and repellency model applications in agriculture. We found extensive support for these models with intercropping schemes, inclusion of flowering plants, and use of plants that repel herbivores or attract them away from the crop. Overall, herbivore suppression, enemy enhancement, and crop damage suppression effects were significantly stronger on diversified crops than on crops with none or fewer associated plant species. However, a relatively small, but significantly negative, mean effect size for crop yield indicated that pest-suppressive diversification schemes interfered with production, in part because of reducing densities of the main crop by replacing it with intercrops or non-crop plants. This first use of meta-analysis to evaluate the effects of diversification schemes, a potentially more powerful tool than tallies of significant positive and negative outcomes (vote-counting), revealed stronger overall effects on all parameters measured compared to previous reviews. Our analysis of the same articles used in a recent review facilitates comparisons of vote-counting and meta-analysis, and shows that pronounced results of the meta-analysis are not well explained by a reduction in articles that met its stricter criteria. Rather, compared to outcome counts, effect sizes were rarely neutral (equal to zero), and a mean effect size value for mixed outcomes could be calculated. Problematic statistical properties of vote-counting were avoided with meta-analysis, thus providing a more precise test of the hypotheses. The unambiguous and encouraging results from this meta-analysis of previous research should motivate ecologists to conduct more mechanistic experiments to improve the odds of designing effective crop diversification schemes for improved pest regulation and enhanced crop yield.


Asunto(s)
Agricultura , Biodiversidad , Ecosistema , Plantas/clasificación
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