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1.
Rev Biol Trop ; 57(1-2): 141-57, 2009.
Artículo en Español | MEDLINE | ID: mdl-19637696

RESUMEN

"Petenes" are small springs and associated streams that drain into wetlands near the coast in karstic areas. We studied composition, distribution, and abundance of the ichthyofauna in Los Petenes region (northwest Campeche). Two petenes displaying different degrees and types of anthropic impact were selected, Hampolol and El Remate. Hampolol has a smaller area but a longer derived stream; it is located within a protected area, but has been invaded by tilapia. El Remate is a popular spa, with no tilapia; it has a larger area but a shorter derived stream. At each "petén", several sites in the main spring, the associated stream, and secondary (temporary) springs were sampled in the rainy and dry seasons. Fishing gear was variable (throw net, gill net, small and large seine nets), but effort was uniform. We recorded temperature, dissolved oxygen, salinity, and depth at each site and season; also, we noted the different types and intensities of anthropic impact (channelization, presence of exotic species, recreational use, etc.) at each petén. We compared the petenes in terms of their environmental quality and fish fauna (composition, distribution, abundance, biomass); we also tested for effects of season and site within each petén. The study found 27 species of fishes, included in 18 genera and eight families, 24 species in Hampolol and 20 in El Remate. The geographical range of 'Cichlasoma' salvini, Rivulus tenuis, Phallichthys fairweatheri, Xiphophorus hellerii, and X maculatus is extended. The dominant species in both seasons was Astyanax (probable hybrids A. aeneus x altior at Hampolol, pure A. altior at El Remate), which contributed most of the abundance and biomass, together with Vieja synspila and Poecilia velifera. A significantly greater overall diversity (H'n=3.31) was recorded in Hampolol compared to El Remate (H'n=2.10). Cluster analysis of sites by species presence allowed distinction of two groupings within each petén: permanent waters (i.e., main spring, stream) vs. temporary sites (secondary springs, which dry out in winter). Environmental parameters (except salinity) presented significant differences by site and season; a canonical correspondence analysis indicated that the distribution of fish assemblages was influenced by the environmental parameters in both seasons. In terms of composition, historical factors play a role in the differences between the fish assemblages of the two petenes, especially concerning the presence of Astyanax hybrids and Xiphophorus spp. in the southern petén (Hampolol) and Poecilia velifera in the northern petén (El Remate).


Asunto(s)
Ecosistema , Peces/clasificación , Humedales , Animales , Biodiversidad , México , Densidad de Población , Estaciones del Año
2.
In Vitro Cell Dev Biol Anim ; 40(1-2): 35-42, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14692828

RESUMEN

The migratory responses of four human melanoma cell lines (A-2058, DEMEL, HTB-63, and HTB-72), using chemotaxis (CTX) and haptotaxis (HPTX) assays, were studied. The attractants were three extracellular matrix components (EMCs), fibronectin, laminin, and collagen type IV. The conditioned media (CM) of each cell line were used to study autocrine and paracrine responses. A screening and sensitive CTX assay was performed, using pertussis toxin (PTX)- treated A-2058 as responder cells; the other melanoma cells and normal cells were used as secretory cells. Autotaxin (ATX), a purified autocrine motility factor, was also used as a chemoattractant. Reverse transcriptase-polymerase chain reaction was used to detect the expression of ATX by all cell lines. The secretion of ATX was determined by Western blot. The invasive capacity of the cell lines was evaluated using Matrigel and ATX as attractant. Chemotaxis responses to EMCs varied. Except for the A-2058 cells, HPTX migration was low. Autocrine and paracrine responses also varied. The migration of PTX-treated A-2058 cells to ATX and to their own CM was abolished. All the melanoma cells expressed ATX, and except for the HTB-72 and normal cells, all secreted ATX. Matrigel was invaded by all the melanoma cell lines except the HTB-72 and normal cells. The migratory properties of human melanoma cells in vitro suggest that they could correlate to their metastatic potential in vivo.


Asunto(s)
Línea Celular Tumoral , Movimiento Celular/fisiología , Melanoma , Animales , Comunicación Autocrina , Bioensayo , Factores Quimiotácticos/metabolismo , Colágeno/metabolismo , Colágeno Tipo IV/metabolismo , Medios de Cultivo Condicionados , Combinación de Medicamentos , Matriz Extracelular/química , Femenino , Fibronectinas/metabolismo , Humanos , Laminina/metabolismo , Masculino , Melanoma/metabolismo , Melanoma/patología , Comunicación Paracrina , Toxina del Pertussis/metabolismo , Proteoglicanos/metabolismo
4.
J Clin Rheumatol ; 11(3): 140-5, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16357732

RESUMEN

BACKGROUND: The importance of past adverse experiences is increasingly recognized in patients with rheumatic disease. OBJECTIVE: The objective of this study was to study the association of physical, verbal, and sexual abuse in patients with rheumatic disorders as compared with healthy volunteers. METHODS: In this case-control study, 500 new patients attending an outpatient rheumatic clinic were interviewed from September 1, 1999, to August 31, 2001. A total of 187 patients with 3 diagnoses were selected: 58 had fibromyalgia (FM), 74 rheumatoid arthritis (RA), and 55 patients with soft tissue rheumatic disease (STRD). All selected patients were asked to complete a questionnaire designed to obtain information regarding demographics and history of verbal, physical, and sexual abuse. A group of 187 healthy control subjects were also included, matched for sex and age. RESULTS: The prevalence of abuse was significantly more common in the rheumatic disease group than in the control group (48.1% versus 15%, P < 0.001). The prevalence of abuse among the groups was as follows: 70.7% of patients with FM reported abuse (24.3% verbal, 60.9% physical, and 14.8% sexual), 35.1% of patients with RA had a history of abuse (42.3% verbal, 30.7% physical, and 0% sexual), whereas 41.8% of patients with STRD reported abuse (43.4% verbal, 43.4% physical, and 0% sexual). When comparing the 3 groups, patients with FM showed a higher prevalence of abuse (P < 0.05). The abuse was usually longstanding (range, 1-10 years), and most abusers were close family members. CONCLUSION: Abuse, both physical and psychologic, was significantly increased in our rheumatic disease population, especially in patients with FM. Further studies are needed to fully establish its role. Questions about abuse may provide important information relative to care of our patients.


Asunto(s)
Violencia Doméstica/estadística & datos numéricos , Fibromialgia/psicología , Enfermedades Reumáticas/psicología , Adulto , Factores de Edad , Instituciones de Atención Ambulatoria , Estudios de Casos y Controles , Consanguinidad , Femenino , Guatemala , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Factores de Tiempo
5.
Chemistry ; 10(10): 2409-20, 2004 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-15146514

RESUMEN

A general study of the regioselective hydroamination of terminal alkynes in the presence of [(eta5-Cp)2Ti(eta2-Me3SiC2SiMe3)] (1), [(eta5-CpEt)2Ti(eta2-Me3SiC2SiMe3)] (CpEt=ethylcyclopentadienyl) (2), and [(eta5-Cp*)2Ti(eta2-Me3SiC2SiMe3)] (Cp*=pentamethylcyclopentadienyl) (3) is presented. While aliphatic amines give mainly the anti-Markovnikov products, anilines and aryl hydrazines yield the Markovnikov isomer as main products. Interestingly, using aliphatic amines such as n-butylamine and benzylamine the different catalysts lead to a significant change in the observed regioselectivity. Here, for the first time a highly selective switch from the Markovnikov to the anti-Markovnikov product is observed simply by changing the catalyst. Detailed theoretical calculations for the reaction of propyne with different substituted anilines and tert-butylamine in the presence of [(eta5-C5H5)Ti(=NR)(NHR)] (R=4-C6H4X; X=H, F, Cl, CH3, 2,6-dimethylphenyl) reveal that the experimentally observed regioselectivity is determined by the relative stability of the corresponding pi-complexes 10. While electrostatic stabilization favors the Markovnikov performance for aniline, the steric repulsive destabilization disfavors the Markovnikov performance for tert-butylamine.

6.
Chemistry ; 10(3): 746-57, 2004 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-14767940

RESUMEN

A practical route for the synthesis of new biologically active 5-HT(2 A) receptor antagonists has been developed. In only three catalytic steps, this class of central nervous system (CNS) active compounds can be synthesized efficiently with high diversity. As the initial step, an anti-Markovnikov addition of amines to styrenes provides an easy route to N-(arylalkyl)piperazines, which constitute the core structure of the active molecules. Here, base-catalyzed hydroamination reactions of styrenes with benzylated piperazine proceeded in high yield even at room temperature. After catalytic debenzylation, the free amines were successfully carbonylated with different aromatic and heteroaromatic halides and carbon monoxide to yield the desired compounds in good to excellent yields. The two key reactions, base-catalyzed hydroamination of styrenes and palladium-catalyzed aminocarbonylation of haloarenes/heterocycles, showed tolerance towards various functional groups, thereby demonstrating the potential to synthesize a wide variety of new derivatives of this promising class of pharmaceuticals.


Asunto(s)
Piperazinas/síntesis química , Antagonistas del Receptor de Serotonina 5-HT2 , Antagonistas de la Serotonina/síntesis química , Aminación , Catálisis , Estructura Molecular , Paladio/química , Piperazinas/farmacología , Antagonistas de la Serotonina/farmacología
7.
J Rheumatol ; 29(7): 1426-9, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12136901

RESUMEN

OBJECTIVE: Bacteria and/or their antigens are thought to play a role in the pathogenesis of reactive arthritis (ReA). Polymerase chain reaction (PCR) using the 16S ribosomal RNA-PCR method was used to identify bacterial DNA in synovial fluid (SF) and tissue (ST) in a well defined group of patients with chronic ReA. In addition, species found were identified by means of sequence analysis. METHODS: We examined 15 ST and 5 SF samples of 15 patients with ReA, 5 ST samples of 5 patients with osteoarthritis (OA), and 8 SF from 8 patients with closed traumatic knee injuries using a nested PCR with universal 16S rRNA primers. In addition, a nested PCR was developed to detect DNA sequences of Salmonella sp. and Mycoplasma sp. Automated sequencing and comparative data analysis (GenBank) were also performed to identify the species. RESULTS: Bacterial DNA was identified in 8 cases, 5 ST and 3 SF; Chlamydia trachomatis (n = 2), Pseudomonas sp. (n = 3), and Bacillus cereus (n = 2) were the most common microorganisms identified. A variety of microorganisms including Clostridium sp., Lactobacillus sp., Pseudomonas migulae, P. fluorescens, and P. putida, and Neisseria meningitidis serogroup B were also identified. In half of the cases (4/8) 2 to 3 bacterial antigens were identified simultaneously. CONCLUSION: Bacterial DNA is present in the joints in patients with chronic ReA. A wide spectrum of bacteria including some not previously associated with ReA were identified. Further studies are needed to establish their exact role in the pathogenesis of ReA and related arthritides.


Asunto(s)
Artritis Reactiva/microbiología , ADN Bacteriano/análisis , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Antígeno HLA-B27/análisis , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Artritis Reactiva/diagnóstico , Artritis Reactiva/epidemiología , Niño , Estudios de Cohortes , Femenino , Humanos , América Latina/etnología , Masculino , México/epidemiología , Persona de Mediana Edad , Prohibitinas , Muestreo , Análisis de Secuencia
8.
Rev. biol. trop ; 57(1/2): 141-157, March-June 2009. graf, mapas, tab
Artículo en Español | LILACS | ID: lil-637707

RESUMEN

Ichthyofauna of karstic wetlands under anthropic impact: the "petenes" of Campeche, Mexico. "Petenes" are small springs and associated streams that drain into wetlands near the coast in karstic areas. We studied composition, distribution, and abundance of the ichthyofauna in Los Petenes region (northwest Campeche). Two petenes displaying different degrees and types of anthropic impact were selected, Hampolol and El Remate. Hampolol has a smaller area but a longer derived stream; it is located within a protected area, but has been invaded by tilapia. El Remate is a popular spa, with no tilapia; it has a larger area but a shorter derived stream. At each "petén", several sites in the main spring, the associated stream, and secondary (temporary) springs were sampled in the rainy and dry seasons. Fishing gear was variable (throw net, gill net, small and large seine nets), but effort was uniform. We recorded temperature, dissolved oxygen, salinity, and depth at each site and season; also, we noted the different types and intensities of anthropic impact (channelization, presence of exotic species, recreational use, etc.) at each petén. We compared the petenes in terms of their environmental quality and fish fauna (composition, distribution, abundance, biomass); we also tested for effects of season and site within each petén. The study found 27 species of fishes, included in 18 genera and eight families, 24 species in Hampolol and 20 in El Remate. The geographical range of ‘Cichlasoma’ salvini, Rivulus tenuis, Phallichthys fairweatheri, Xiphophorus hellerii, and X. maculatus is extended. The dominant species in both seasons was Astyanax (probable hybrids A. aeneus × altior at Hampolol, pure A. altior at El Remate), which contributed most of the abundance and biomass, together with Vieja synspila and Poecilia velifera. A significantly greater overall diversity (H’n=3.31) was recorded in Hampolol compared to El Remate (H’n=2.10). Cluster analysis of sites by species presence allowed distinction of two groupings within each petén: permanent waters (i.e., main spring, stream) vs. temporary sites (secondary springs, which dry out in winter). Environmental parameters (except salinity) presented significant differences by site and season; a canonical correspondence analysis indicated that the distribution of fish assemblages was influenced by the environmental parameters in both seasons. In terms of composition, historical factors play a role in the differences between the fish assemblages of the two petenes, especially concerning the presence of Astyanax hybrids and Xiphophorus spp. in the southern petén (Hampolol) and Poecilia velifera in the northern petén (El Remate). Rev. Biol. Trop. 57 (1-2): 141-157. Epub 2009 June 30.


Los petenes son pequeños manantiales y arroyos asociados que drenan a sistemas palustres en áreas cársticas costeras. Se estudió la composición, distribución y abundancia de la ictiofauna en dos petenes del noroeste de Campeche, en el manantial principal, el arroyo asociado, y pequeños ojos de agua secundarios (temporales), en dos épocas del año. Se registraron variables ambientales y tipos de impacto antrópico en cada petén. Se encontraron en total 27 especies de peces, con extensiones de ámbito de ‘Cichlasoma’ salvini, Rivulus tenuis, Phallichthys fairweatheri, Xiphophorus hellerii y X. maculatus. La especie dominante en ambas épocas fue Astyanax (probables híbridos A. aeneus × altior en Hampolol, A. altior en El Remate). Hubo diferencia significativa en diversidad entre ambos petenes. El análisis de conglomerados diferenció dos agrupaciones dentro de cada petén: aguas permanentes y sitios temporales. Las variables ambientales (excepto salinidad) presentaron diferencias significativas por sitio y época; un análisis de correspondencia canónica indicó que la distribución de los conjuntos de peces tuvo influencia de las variables ambientales en ambas temporadas. En términos de composición, los factores históricos juegan un papel en las diferencias ictiológicas entre ambos petenes, sobre todo por lo que concierne a la presencia de híbridos de Astyanax, así como Xiphophorus hellerii en el petén del sur (Hampolol) y de Poecilia velifera en el petén del norte (El Remate).


Asunto(s)
Animales , Ecosistema , Peces/clasificación , Humedales , Biodiversidad , México , Densidad de Población , Estaciones del Año
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