Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Más filtros

Intervalo de año de publicación
1.
Bull Environ Contam Toxicol ; 111(2): 20, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37530948

RESUMEN

Total mercury (Hg) and selenium (Se) contents were determined in oysters Saccostrea palmula and Crassostrea corteziensis soft tissues from four coastal lagoons of the southeastern Gulf of California. The annual Hg mean concentrations for S. palmula (0.09 ± 0.04 µg g- 1, wet weight) and C. corteziensis (0.08 ± 0.04 µg g- 1) were similar (p ˃ 0.05) among the lagoons and did not exceed the limit established by the Norma Oficial Mexicana and World Health Organization (< 1.0 µg g- 1 Hg). On the other hand, the annual mean concentrations of Se for S. palmula (3.34 ± 0.96 µg g- 1) and C. corteziensis (2.79 ± 0.89 µg g- 1) were higher (p < 0.05) in El Colorado lagoon. The Se/Hg molar ratios were above 1; the positive selenium health benefit value index suggested that Se load in oysters could reduce the Hg potential toxic effect. The hazard quotient for Hg in both species was below 1. Therefore, the consumption of oysters does not represent a risk due to Hg ingestion.


Asunto(s)
Crassostrea , Mercurio , Selenio , Contaminantes Químicos del Agua , Animales , Humanos , Mercurio/toxicidad , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Medición de Riesgo
2.
Transfusion ; 56(7): 1883-90, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27185049

RESUMEN

BACKGROUND: Blood transfusion safety is based on reliable donor screening for transmissible infections such as the hepatitis C virus (HCV) infection. STUDY DESIGN AND METHODS: A novel HCV core-specific antibody was assayed on random single donations from 2007 first-time blood donors who tested negative for anti-HCV and HCV RNA on routine screening. Sample collection broke the code between donations and donors for ethical reasons. RESULTS: Forty-two donations (2.1%) displayed reactivity in the novel test. The specificity of the reactivity was evaluated by a peptide inhibition assay, and testing against additional nonoverlapping HCV core peptide epitopes and other HCV antigens was performed on these samples. Six donations (14.3%; 0.30% from the total) were considered to contain anti-HCV after such supplemental testing. HCV RNA detection was also performed in peripheral blood mononuclear cells (PBMNCs) and serum or plasma samples from reactive donors after virus concentration by ultracentrifugation. HCV RNA tested negative in all PBMNCs samples, and a very low amount of viral genome was detected in serum or plasma concentrates from three anti-HCV core-reactive donors (7.1%) but not among concentrates from 100 randomly selected nonreactive donors. Sequencing of these polymerase chain reaction products revealed differences between the isolates that excluded partially sample contamination from a common source. CONCLUSION: These findings argue in favor of an ongoing occult HCV infection among these blood donors and account for some rather low, but perhaps not negligible, infection risk for such donations. Future studies involving larger samples of donations from traceable donors would enlighten the significance of these findings for the viral safety of the blood supply.


Asunto(s)
Donantes de Sangre , Selección de Donante/métodos , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/diagnóstico , Seguridad de la Sangre , Femenino , Hepatitis C/sangre , Humanos , Masculino , ARN Viral/sangre , Reacción a la Transfusión
3.
Biomed Pharmacother ; 173: 116381, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38452655

RESUMEN

Curcumin is a natural molecule widely tested in preclinical and clinical studies due to its antioxidant and anti-inflammatory activity. Nevertheless, its high hydrophobicity and low bioavailability limit in vivo applications. To overcome curcumin´s drawbacks, small extracellular vesicles (sEVs) have emerged as potential drug delivery systems due to their non-immunogenicity, nanometric size and amphiphilic composition. This work presents curcumin cargo into milk sEV structure and further in vitro and in vivo evaluation as a therapeutic nanoplatform. The encapsulation of curcumin into sEV was performed by two methodologies under physiological conditions: a passive incorporation and active cargo employing saponin. Loaded sEVs (sEVCurPas and sEVCurAc) were fully characterized by physicochemical techniques, confirming that neither methodology affects the morphology or size of the nanoparticles (sEV: 113.3±5.1 nm, sEVCurPas: 127.0±4.5 nm and sEVCurAc: 98.5±3.6 nm). Through the active approach with saponin (sEVCurAc), a three-fold higher cargo was obtained (433.5 µg/mL) in comparison with the passive approach (129.1 µg/mL). These sEVCurAc were further evaluated in vitro by metabolic activity assay (MTT), confocal microscopy, and flow cytometry, showing a higher cytotoxic effect in the tumoral cells RAW264.7 and HepG2 than in primary hepatocytes, specially at high doses of sEVCurAc (4%, 15% and 30% of viability). In vivo evaluation in an experimental model of liver fibrosis confirmed sEVCurAc therapeutic effects, leading to a significant decrease of serum markers of liver damage (ALT) (557 U/L to 338 U/L with sEVCurAc therapy) and a tendency towards decreased liver fibrogenesis and extracellular matrix (ECM) deposition.


Asunto(s)
Curcumina , Vesículas Extracelulares , Saponinas , Humanos , Animales , Curcumina/química , Leche , Cirrosis Hepática
4.
J Dent Educ ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627911

RESUMEN

INTRODUCTION: Three-dimensional (3D)-printing technology can provide customizable simulations, but its effects on patient care quality have not been well studied. This study aimed to assess the impact of practicing with patient-specific 3D-printed teeth models on the quality of patients' dental preparations performed by students transitioning to clinical training. Accordingly, the quality of posterior crown preparations was evaluated by objectively analyzing digital scans and grades in two groups: the study group, which practiced beforehand with patient-specific 3D-printed teeth models, and the control group, which did not practice with these models. METHODS: All 78 fourth-year dental students who had just finished their fixed prosthodontics course at the simulation laboratory with training on phantom heads and without previous clinical experience in crown preparations were invited to participate in the study. Sixty-eight agreed to take part and were randomly divided into a study group that practiced crown preparations on 3D-printed models of their own patient's teeth and a control group that did not practice with 3D-printed models and started their clinical work straightforwardly after simulation training. Students completed validated perception questionnaires on self-confidence and clinical skills before and after the protocol, which were compared using a chi-squared test. Crown preparations performed on 3D-printed models and then on patients were digitally scanned and objectively graded by prepCheck software for critical parameters, such as undercuts, taper, and occlusion reduction. Non-parametric tests were used to compare preparations on 3D-printed models and on patients performed by the study group and those on patients made by the control group. RESULTS: Initially, both groups reported similar perceptions of self-confidence and clinical skills levels. The study group significantly improved both aspects after the protocol. Analysis of the scanned preparations demonstrated that the study group removed less tooth structure from actual patients than from the initial 3D-printed models. In contrast, the control group showed excess occlusal clearance in their patients compared to the study group. CONCLUSIONS: Practicing patient-specific 3D-printed teeth before performing procedures clinically appears to enhance preparation quality and minimize unnecessary tooth reduction in early clinical experiences.

6.
Neurodegener Dis ; 8(6): 455-64, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21389687

RESUMEN

BACKGROUND: Allosteric modulation of γ-secretase is an attractive therapeutic approach for the treatment of Alzheimer's disease. We recently identified a novel γ-secretase modulator, GSM-10h, which effectively lowers Aß42 production in cells and in amyloid precursor protein transgenic mice. OBJECTIVE: Here, we describe the in vivo characterization of GSM-10h in a model of endogenous Aß production. METHODS: Rats were administered orally with GSM-10h, and the effect on Aß levels in peripheral and central compartments was determined. In addition, the effect of GSM-10h on Notch processing was assessed. RESULTS: Acute administration of GSM-10h to rats causes a dose-dependent decrease in the level of Aß42 in plasma, CSF and brain, with little effect on the level of Aß40 in these compartments. The magnitude of Aß42 lowering in the CSF and brain was further enhanced upon sub-chronic administration of GSM-10h. No deleterious effect on Notch processing was evident in either of these studies. To further explore the dynamics of Aß42 reduction in peripheral and CNS compartments, a time course study was conducted. In all compartments, the decrease in Aß42 was greatest at 6 h after administration of GSM-10h. This decrease in Aß42 was maintained for 9-15 h, after which time Aß42 levels returned to baseline levels. Encouragingly, no rebound in Aß42 levels beyond baseline levels was observed. CONCLUSIONS: These findings support the γ-secretase modulator profile of GSM-10h, and highlight the utility of the rat for assessing the pre-clinical efficacy of γ-secretase modulators.


Asunto(s)
Acetatos/farmacología , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Química Encefálica/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Fragmentos de Péptidos/metabolismo , Piperidinas/farmacología , Péptidos beta-Amiloides/sangre , Péptidos beta-Amiloides/líquido cefalorraquídeo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Recuento de Células , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/genética , Masculino , Neuronas/metabolismo , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/líquido cefalorraquídeo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Receptores Notch/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Timo/citología , Timo/efectos de los fármacos , Factor de Transcripción HES-1
7.
J Neurosci Res ; 88(2): 346-59, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19658199

RESUMEN

FTY720, an oral sphingosine 1-phosphate (S1P) receptor modulator, has shown efficacy in phase II trials in patients with relapsing-remitting multiple sclerosis (MS). Although this molecule is thought to immunosuppress by inhibiting lymphocyte egress from the lymph nodes, the full spectrum of FTY720's actions has not yet been uncovered. In this study, we investigated the effects of FTY720 treatment on disease severity and histopathology of MOG-induced experimental autoimmune encephalomyelitis (EAE) in the dark agouti (DA) rat, a model that closely mimics several features of MS. The effects of FTY720 on T-cell subsets, anti-MOG antibody production, and mRNA expression of a number of cytokines and other genes were also examined. Commencement of treatment before disease onset prevented the appearance of clinical disease. Therapeutic treatment after established disease reduced clinical scores and substantially attenuated inflammation, demyelination, and axon loss. EAE suppression was associated with a reduction in all measured T-cell subsets in blood and spleen and a significant decrease in serum IgG(2a) levels. However, in the lymph nodes, all T-cell subsets except for naïve T cells and recent thymic emigrants remained unaffected. In addition, FTY720 treatment led to a significant inhibition in interferon-gamma, inducible nitric oxide synthase, and glial cell line-derived neurotrophic factor mRNA expression in the MOG-EAE spinal cord. In conclusion, our findings indicate that FTY720-mediated S1P receptor modulation ameliorates chronic relapsing MOG-EAE by suppressing both cellular and humoral immune responses.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Inmunosupresores/farmacología , Glicoles de Propileno/farmacología , Esfingosina/análogos & derivados , Animales , Autoanticuerpos/metabolismo , Axones/efectos de los fármacos , Axones/inmunología , Axones/patología , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/patología , Femenino , Clorhidrato de Fingolimod , Expresión Génica/efectos de los fármacos , Linfocitos/efectos de los fármacos , Esclerosis Múltiple , Proteínas de la Mielina , Glicoproteína Asociada a Mielina , Glicoproteína Mielina-Oligodendrócito , Ratas , Ratas Endogámicas , Proteínas Recombinantes , Índice de Severidad de la Enfermedad , Esfingosina/farmacología , Médula Espinal/efectos de los fármacos , Médula Espinal/inmunología , Médula Espinal/patología , Factores de Tiempo
8.
Acta Odontol Latinoam ; 33(2): 104-111, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920612

RESUMEN

Candida dubliniensis (Cd) and Candida albicans (Ca) are the most frequently isolated yeasts in HIV+ patients. Some of the enzymes produced by these yeasts are considered virulence factors since they contribute to pathogenicity of Candida spp. The aim of the present study was to compare production of enzymes such as phospholipase (Ph), proteinase (P), and hemolysin (H) by Cd and Ca strains isolated from periodontal HIV-positive patients receiving and not receiving highly active antiretroviral therapy (HAART). Subgingival biofilm samples were obtained using paper points, and a sample of oral mucosa was taken using a swab. Phenotypic and molecular methods were used to isolate 39 strains of Candida, including 25 strains of Cd and 14 strains of Ca, obtained from 33 periodontal pocket samples and 6 oral mucosa samples collected from 15 HIV+ patients (8 receiving and 7 not receiving HAART). Malt egg-yolk agar, albumin agar and blood agar were used to evaluate pH, P and H production respectively. The strains were inoculated in duplicate and incubated at 37 ºC. Colony and halo diameters were measured. A greater proportion of Ca was observed in patients not receiving HAART, and a higher proportion of Cd was observed in those under HAART, Chi2 p< 0.001. Phospholipase production was observed in 92.9% percent of isolated Ca strains but in none of the isolated Cd strains. Proteinase production was high in Ca and Cd strains isolated from patients not receiving HAART. Hemolysin production was observed in all the studied strains, though it was significantly higher (p=0.04) in Ca and Cd strains isolated from patients not receiving HAART. To sum up, the proportion of Candida dubliniensis strains was highest in the subgingival biofilm of patients receiving HAART, and Cd strains were found to express fewer virulence factors than Ca strains.


Las levaduras más aisladas en pacientes VIH+ son Candida dubliniensis (Cd) y Candida albicans (Ca). Algunas de sus enzimas constituyen factores de virulencia ya que favorecen la diseminación tisular. El objetivo fue comparar la producción de enzimas como fosfolipasa (F), proteinasa (P) y hemolisina (H) en cepas de Cd y Ca aisladas de pacientes VIH+ tratados y no tratados con antirretrovirales (TARGA). Se realizó la toma del biofilm de placa subgingival con conos de papel y la muestra de la mucosa bucal con hisopo. Se aislaron y tipificaron por métodos fenotípicos y moleculares 39 cepas: 25 de Cd y 14 Ca, obtenidas 33 de bolsas periodontales y 6 de mucosa bucal de 15 pacientes VIH+ (8 con y 7 sin tratamiento). Se utilizó agar malta con yema de huevo, agar albúmina y agar sangre para demostrar la producción de F, P y H, respectivamente. Se inocularon por duplicado e incubaron a 37°C. Se midieron los diámetros de las colonias y los de hidrólisis alrededor de las mismas. Se observó mayor proporción de Ca en los pacientes sin tratamiento y mayor proporción de Cd en los con tratamiento; Chi2 p< 0.001. El 92,9% de las Ca estudiadas, fueron productoras de fosfolipasa. En tanto que ninguna Cd produjo la enzima. En cuanto a la producción de proteinasa se observa una alta producción tanto en las cepas de Ca, como en las Cd aisladas en los pacientes no tratados. Todas las cepas estudiadas produjeron hemolisina, observándose una diferencia estadísticamente significativa (p=0,04) en ambas especies a favor de la alta producción de la enzima en las cepas obtenidas de pacientes no tratados. Podemos concluir que en el biofilm subgingival, en los pacientes bajo TARGA, se aíslan mayor proporción de Candida dubliniensis las cuales expresan menos factores de virulencia.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Biopelículas/crecimiento & desarrollo , Candida albicans/enzimología , Candida albicans/aislamiento & purificación , Candida/enzimología , Candida/aislamiento & purificación , Candidiasis Bucal/microbiología , Encía/microbiología , Infecciones por VIH/complicaciones , Candida/clasificación , Candida/genética , Candida albicans/genética , Candidiasis Bucal/complicaciones , Genotipo , Infecciones por VIH/microbiología , Humanos , Mucosa Bucal/microbiología , Fenotipo , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética
9.
World J Gastroenterol ; 14(42): 6481-7, 2008 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-19030199

RESUMEN

AIM: To determine the association of Helicobacter pylori (H pylori) CagA(+) infection and pro-inflammatory polymorphisms of the genes interleukin (IL)-1RN and IL-1B with the risk of gastric atrophy and peptic ulcers in a dyspeptic population in Costa Rica, a country with high incidence and mortality of gastric cancer. METHODS: Seven biopsy specimens, a fasting blood sample and a questionnaire concerning nutritional and sociodemographic factors were obtained from 501 consecutive patients who had undergone endoscopy for dyspeptic symptoms. A histopathological diagnosis was made. Pepsinogen concentrations were analyzed by enzyme linked immunosorbent assay (ELISA). Infection with H pylori CagA(+) was determined by serology and polymerase chain reaction (PCR). IL-1B and IL-1RN polymorphisms genotyping was performed by PCR-restriction fragment length polymorphism (PCR-RFLP) and PCR respectively. RESULTS: In this dyspeptic population, 86% were H pylori positive and of these, 67.8% were positive for CagA. Atrophic antral gastritis (AAG) was associated with CagA(+) status [odd ratio (OR) = 4.1; P < 0.000] and fruit consumption (OR = 0.3; P < 0.00). Atrophic body gastritis (ABG) was associated with pepsinogen PGI/PGII < 3.4 (OR = 4.9; P < 0.04) and alcohol consumption (OR = 7.3; P < 0.02). Duodenal ulcer was associated with CagA(+) (OR = 2.9; P < 0.04) and smoking (OR = 2.4; P < 0.04). PGI < 60 microg/L as well as PGI/PGII < 3.4 were associated with CagA(+). CONCLUSION: In a dyspeptic population in Costa Rica, H pylori CagA(+) is not associated with ABG, but it is a risk factor for AAG. The pro-inflammatory cytokine polymorphisms IL-1B + 3945 and IL-1RN are not associated with the atrophic lesions of this dyspeptic population.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Gastritis/genética , Infecciones por Helicobacter/genética , Helicobacter pylori/genética , Proteína Antagonista del Receptor de Interleucina 1/genética , Interleucina-1beta/genética , Polimorfismo Genético , Consumo de Bebidas Alcohólicas/efectos adversos , Atrofia , Biopsia , Costa Rica , Dieta/efectos adversos , Dispepsia/genética , Dispepsia/inmunología , Dispepsia/microbiología , Femenino , Gastritis/inmunología , Gastritis/microbiología , Gastritis/patología , Gastroscopía , Predisposición Genética a la Enfermedad , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/microbiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Pepsinógeno A/sangre , Pepsinógeno C/sangre , Úlcera Péptica/genética , Úlcera Péptica/inmunología , Úlcera Péptica/microbiología , Medición de Riesgo , Factores de Riesgo , Fumar/efectos adversos , Encuestas y Cuestionarios
10.
Acta odontol. latinoam ; Acta odontol. latinoam;33(2): 104-111, Sept. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1130740

RESUMEN

ABSTRACT Candida dubliniensis (Cd) and Candida albicans (Ca) are the most frequently isolated yeasts in HIV+ patients. Some of the enzymes produced by these yeasts are considered virulence factors since they contribute to pathogenicity of Candida spp. The aim of the present study was to compare production of enzymes such as phospholipase (Ph), proteinase (P), and hemolysin (H) by Cd and Ca strains isolated from periodontal HIV-positive patients receiving and not receiving highly active antiretroviral therapy (HAART). Subgingival biofilm samples were obtained using paper points, and a sample of oral mucosa was taken using a swab. Phenotypic and molecular methods were used to isolate 39 strains of Candida, including 25 strains of Cd and 14 strains of Ca, obtained from 33 periodontal pocket samples and 6 oral mucosa samples collected from 15 HIV+ patients (8 receiving and 7 not receiving HAART). Malt egg-yolk agar, albumin agar and blood agar were used to evaluate pH, P and H production respectively. The strains were inoculated in duplicate and incubated at 37 ºC. Colony and halo diameters were measured. A greater proportion of Ca was observed in patients not receiving HAART, and a higher proportion of Cd was observed in those under HAART, Chi2 p< 0.001. Phospholipase production was observed in 92.9% percent of isolated Ca strains but in none of the isolated Cd strains. Proteinase production was high in Ca and Cd strains isolated from patients not receiving HAART. Hemolysin production was observed in all the studied strains, though it was significantly higher (p=0.04) in Ca and Cd strains isolated from patients not receiving HAART. To sum up, the proportion of Candida dubliniensis strains was highest in the subgingival biofilm of patients receiving HAART, and Cd strains were found to express fewer virulence factors than Ca strains.


RESUMEN Las levaduras más aisladas en pacientes VIH+ son Candida dubliniensis (Cd) y Candida albicans (Ca). Algunas de sus enzimas constituyen factores de virulencia ya que favorecen la diseminación tisular. El objetivo fue comparar la producción de enzimas como fosfolipasa (F), proteinasa (P) y hemolisina (H) en cepas de Cd y Ca aisladas de pacientes VIH+ tratados y no tratados con antirretrovirales (TARGA). Se realizó la toma del biofilm de placa subgingival con conos de papel y la muestra de la mucosa bucal con hisopo. Se aislaron y tipificaron por métodos fenotípicos y moleculares 39 cepas: 25 de Cd y 14 Ca, obtenidas 33 de bolsas periodontales y 6 de mucosa bucal de 15 pacientes VIH+ (8 con y 7 sin tratamiento). Se utilizó agar malta con yema de huevo, agar albúmina y agar sangre para demostrar la producción de F, P y H, respectivamente. Se inocularon por duplicado e incubaron a 37°C. Se midieron los diámetros de las colonias y los de hidrólisis alrededor de las mismas. Se observó mayor proporción de Ca en los pacientes sin tratamiento y mayor proporción de Cd en los con tratamiento; Chi2 p< 0.001. El 92,9% de las Ca estudiadas, fueron productoras de fosfolipasa. En tanto que ninguna Cd produjo la enzima. En cuanto a la producción de proteinasa se observa una alta producción tanto en las cepas de Ca, como en las Cd aisladas en los pacientes no tratados. Todas las cepas estudiadas produjeron hemolisina, observándose una diferencia estadísticamente significativa (p=0,04) en ambas especies a favor de la alta producción de la enzima en las cepas obtenidas de pacientes no tratados. Podemos concluir que en el biofilm subgingival, en los pacientes bajo TARGA, se aíslan mayor proporción de Candida dubliniensis las cuales expresan menos factores de virulencia.


Asunto(s)
Humanos , Candida/aislamiento & purificación , Candida/enzimología , Candida albicans/aislamiento & purificación , Candida albicans/enzimología , Candidiasis Bucal/microbiología , Infecciones por VIH/complicaciones , Biopelículas/crecimiento & desarrollo , Terapia Antirretroviral Altamente Activa/métodos , Encía/microbiología , Fenotipo , Candida/clasificación , Candida/genética , Candida albicans/genética , Candidiasis Bucal/complicaciones , Infecciones por VIH/microbiología , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética , Genotipo , Mucosa Bucal/microbiología
11.
PLoS One ; 10(10): e0139682, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26444006

RESUMEN

INTRODUCTION: Preeclampsia is a maternal hypertensive disorder with uncertain etiology and a leading cause of maternal and fetal mortality worldwide, causing nearly 40% of premature births delivered before 35 weeks of gestation. The first stage of preeclampsia is characterized by reduction of utero-placental blood flow which is reflected in high blood pressure and proteinuria during the second half of pregnancy. In human placenta androgens derived from the maternal and fetal adrenal glands are converted into estrogens by the enzymatic action of placental aromatase. This implies that alterations in placental steroidogenesis and, subsequently, in the functionality or bioavailability of placental aromatase may be mechanistically involved in the pathophysiology of PE. METHODS: Serum samples were collected at 32-36 weeks of gestation and placenta biopsies were collected at time of delivery from PE patients (n = 16) and pregnant controls (n = 32). The effect of oxygen tension on placental cells was assessed by incubation JEG-3 cells under 1% and 8% O2 for different time periods, Timed-mated, pregnant New Zealand white rabbits (n = 6) were used to establish an in vivo model of placental ischemia (achieved by ligature of uteroplacental vessels). Aromatase content and estrogens and androgens concentrations were measured. RESULTS: The protein and mRNA content of placental aromatase significantly diminished in placentae obtained from preeclamptic patients compared to controls. Similarly, the circulating concentrations of 17-ß-estradiol/testosterone and estrone/androstenedione were reduced in preeclamptic patients vs. controls. These data are consistent with a concomitant decrease in aromatase activity. Aromatase content was reduced in response to low oxygen tension in the choriocarcinoma JEG-3 cell line and in rabbit placentae in response to partial ligation of uterine spiral arteries, suggesting that reduced placental aromatase activity in preeclamptic patients may be associated with chronic placental ischemia and hypoxia later in gestation. CONCLUSIONS: Placental aromatase expression and functionality are diminished in pregnancies complicated by preeclampsia in comparison with healthy pregnant controls.


Asunto(s)
Aromatasa/deficiencia , Aromatasa/metabolismo , Isquemia/metabolismo , Placenta/metabolismo , Preeclampsia/metabolismo , Adulto , Andrógenos/metabolismo , Androstenodiona/metabolismo , Animales , Estudios de Casos y Controles , Línea Celular Tumoral , Coriocarcinoma/metabolismo , Estradiol/metabolismo , Estrógenos/metabolismo , Estrona/metabolismo , Femenino , Edad Gestacional , Humanos , Embarazo , Nacimiento Prematuro/metabolismo , Estudios Prospectivos , ARN Mensajero/metabolismo , Conejos , Testosterona/metabolismo
12.
Rev Biol Trop ; 50(1): 309-19, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12298258

RESUMEN

We report lichen cover change over a 20 years period for the Costa Rican capitol city. Foliaceous lichen cover was measured with a 10 x 10 cm template positioned 1.5 m above ground on the south, east, north and west sides of ten phorophytic trees per station (11 stations) from 1976 through 1997. Results were compared with previous measurements along an urban transect (at three heights above ground) and in a rural station. Lichen cover was correlated with traffic density and varied between stations and years. Mean lichen cover was 23% in 1976, 12% in 1986, 9% in 1990 and 22% in 1997. Most stations suffered a large cover reduction after 1976 but improved after 1990, possibly reflecting improved traffic regulations and elimination of lead (Pb) from gasoline. Cover values by cardinal orientation were: west 17%, east 14%, north 13% and south 12%. Sidewalks of streets with more traffic had lower cover values. In the rural station, cover was lower than expected (possibly because of climate), and was not correlated with height above ground or cardinal orientation, in contrast with temperate regions. In polluted cities human activity should concentrate above the first floor of buildings (particularly in hospitals or schools) because pollution was found to concentrate in the first 2 m above ground.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Líquenes , Costa Rica , Humanos , Clima Tropical
13.
Rev Biol Trop ; 50(1): 321-5, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12298260

RESUMEN

Lichens are increasingly used worldwide as air quality biomonitors because they are efficient, easy and cheap, but validation studies of the methodology are scarce. Three foliose lichen biomonitoring methods were compared by field tests (in the tropical urban habitat of San José, Costa Rica) and laboratory simulations: (1) the 100 uniform squares template traditionally used in North America, (2) the European 200 uniform points template and (3) a new computer-generated random points template (10 x 20 cm) in two versions: 100 points and 50 points. Repeated measurement by the same observer causes a variation of 2-14% and the templates' error is 0.2-11%. We recommend the 100 random point template (applied to four sides of trunk) for ecological studies and the 50 random points template (applied to side with greatest lichen cover) for biomonitoring because it reduces time and costs by nearly 50% but still has acceptable reliability values.


Asunto(s)
Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Líquenes , Análisis de Varianza , Monitoreo del Ambiente/economía , Reproducibilidad de los Resultados
14.
Med Sci Sports Exerc ; 44(1): 2-11, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21685814

RESUMEN

PURPOSE: The purpose of our study was to assess the effects of an 8-wk intrahospital combined circuit weight and aerobic training program performed by children with cystic fibrosis (of low-moderate severity and stable clinical condition) on the following outcomes: cardiorespiratory fitness (VO2peak) and muscle strength (five-repetition maximum (5RM) bench press, 5RM leg press, and 5RM seated row) (primary outcomes) and pulmonary function (forced vital capacity, forced expiratory volume in 1 s), weight, body composition, functional mobility (Timed Up and Down Stairs and 3-m Timed Up and Go tests), and quality of life (secondary outcomes). We also determined the effects of a detraining period (4 wk) on the aforementioned outcomes. METHODS: We performed a randomized controlled trial design. Eleven participants in each group (controls: 7 boys, age = 11 ± 3 yr, body mass index = 17.2 ± 0.8 kg · m(-2) (mean ± SEM); intervention: 6 boys, age = 10 ± 2 yr, body mass index = 18.4 ± 1.0 kg · m(-2)) started the study. RESULTS: Adherence to training averaged 95.1% ± 7.4%. We observed a significant group × time interaction effect (P = 0.036) for VO2peak. In the intervention group, VO2peak significantly increased with training by 3.9 mL · kg(-1) · min(-1) (95% confidence interval = 1.8-6.1 mL · kg(-1) · min(-1), P = 0.002), whereas it decreased during the detraining period (-3.4 mL · kg(-1) · min(-1), 95% confidence interval = -5.7 to -1.7 mL · kg(-1) · min(-1), P = 0.001). In contrast, no significant changes were observed during the study period within the control group. Although significant improvements were also observed after training for all 5RM strength tests (P < 0.001 for the interaction effect), the training improvements were not significantly decreased after the detraining period in the intervention group (all P > 0.1 for after training vs detraining). We found no significant training benefits in any of the secondary outcomes. CONCLUSIONS: A short-term combined circuit weight and aerobic training program performed in a hospital setting induces significant benefits in the cardiorespiratory fitness and muscle strength of children with cystic fibrosis.


Asunto(s)
Fibrosis Quística/terapia , Terapia por Ejercicio/métodos , Levantamiento de Peso/fisiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Consumo de Oxígeno/fisiología , Cooperación del Paciente , Aptitud Física/fisiología , Calidad de Vida , Pruebas de Función Respiratoria , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
15.
Behav Brain Res ; 195(1): 180-6, 2008 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-18765258

RESUMEN

5-HT4 agonists are currently being developed for the treatment of Alzheimer's disease and have previously been demonstrated to improve cognitive performance in a variety of tests but none that specifically test attention. Here we characterise the 5-HT4 partial agonist SL65.0155 compared to the reference drug, nicotine, in a test that is used to measure attention in rats, the five-choice serial reaction time task (5CSRTT). SL65.0155 (0.1 or 1 mg/kg s.c) and nicotine (0.2 mg/kg s.c.) were tested in protocols using fixed or variable stimulus durations. SL65.0155 improved performance by virtue of reducing incorrect responses and increasing % correct trials. Perseverative responses were reduced by SL65.0155, and latency during incorrect trials was increased following treatment with 0.1 mg/kg SL65.0155. Nicotine, as previously reported, improved performance in several parameters in the 5CSRTT, including response latencies, errors of omission and correct responses in both the baseline and variable stimulus protocol. These data suggest 5-HT4 agonists may have beneficial effects on attention and thereby may be useful for the treatment of cognitive deficits.


Asunto(s)
Conducta de Elección/efectos de los fármacos , Dioxanos/farmacología , Oxadiazoles/farmacología , Tiempo de Reacción/efectos de los fármacos , Aprendizaje Seriado/efectos de los fármacos , Animales , Atención/efectos de los fármacos , Atención/fisiología , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Conducta de Elección/fisiología , Dioxanos/administración & dosificación , Inyecciones Subcutáneas , Masculino , Memoria/efectos de los fármacos , Memoria/fisiología , Nicotina/administración & dosificación , Nicotina/farmacología , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/farmacología , Oxadiazoles/administración & dosificación , Ratas , Tiempo de Reacción/fisiología , Receptores de Serotonina 5-HT4/fisiología , Aprendizaje Seriado/fisiología , Agonistas del Receptor de Serotonina 5-HT4
16.
Hosp. Aeronáut. Cent ; 13(2): 128-33, 2018.
Artículo en Español | BINACIS, LILACS | ID: biblio-1021099

RESUMEN

Introducción: Los Trastornos del Espectro Autista (TEA) son un grupo de complejos trastornos del desarrollo cerebral que se caracterizan por dificultades en la comunicación y la interacción social y por un repertorio de intereses y actividades restringido y repetitivo. Se está asistiendo a un incremento de los pacientes con este diagnóstico. Si bien las causas no están determinadas, se puede atribuir a una mayor concientización sobre el autismo y a la capacidad de detección de los profesionales. Material y Método: Estudio descriptivo. Investigación Cualitativa. Observación. Realizado entre enero y agosto de 2018. M-Chat: Lista de verificación para el autismo en niños pequeños. Criterios diagnósticos DSM V. Signos de alerta. Resultados: A través del trabajo interdisciplinario, de la oportuna observación y aplicación de la herramienta de pesquisa M-Chat destinada a la evaluación de factores de riesgo para autismo, se ha evidenciado la presencia de un número mayor de niños que presentaron signos acordes a un diagnostico dentro del espectro. Conclusión: La detección temprana es una variable determinante de un mejor pronóstico. Debido a la ausencia de marcadores biológicos, el principal medio de detección es la observación. Es por esto que el diagnóstico y la intervención temprana es la mejor respuesta, siendo importante la difusión sobre signos de alerta


Introduction: Autistic Spectrum Disorders (ASD) are a group of complex disorders of brain development characterized by difficulties in communication and social interaction and by a repertoire of interests and restricted and repetitive activities. We are seeing an increase in patients with this diagnosis. Although the causes are not determined, it can be attributed to a greater awareness of autism and the detection capacity of professionals. Material and Method: Descriptive study. Qualitative research. Observation. Made between January and August 2018. M-Chat: Checklist for autism in young children. Diagnostic criteria DSM V. Warning signs. Results: Through the interdisciplinary work, the timely observation and application of the M-Chat research tool aimed at the evaluation of risk factors for autism, the presence of a greater number of children who showed signs according to a diagnostic within the spectrum. Conclusion: Early detection is a determining variable of a better prognosis. Due to the absence of biological markers, the main means of detection is observation. This is why diagnosis and early intervention is the best response, being important the diffusion on warning signs.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Observación , Intervención Médica Temprana , Trastorno del Espectro Autista/prevención & control , Lista de Verificación
17.
J Neurochem ; 100(3): 802-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17156133

RESUMEN

Generation and deposition of the amyloid beta (Abeta) peptide following proteolytic processing of the amyloid precursor protein (APP) by BACE-1 and gamma-secretase is central to the aetiology of Alzheimer's disease. Consequently, inhibition of BACE-1, a rate-limiting enzyme in the production of Abeta, is an attractive therapeutic approach for the treatment of Alzheimer's disease. We have designed a selective non-peptidic BACE-1 inhibitor, GSK188909, that potently inhibits beta-cleavage of APP and reduces levels of secreted and intracellular Abeta in SHSY5Y cells expressing APP. In addition, we demonstrate that this compound can effectively lower brain Abeta in vivo. In APP transgenic mice, acute oral administration of GSK188909 in the presence of a p-glycoprotein inhibitor to markedly enhance the exposure of GSK188909 in the brain decreases beta-cleavage of APP and results in a significant reduction in the level of Abeta40 and Abeta42 in the brain. Encouragingly, subchronic dosing of GSK188909 in the absence of a p-glycoprotein inhibitor also lowers brain Abeta. This pivotal first report of central Abeta lowering, following oral administration of a BACE-1 inhibitor, supports the development of BACE-1 inhibitors for the treatment of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Péptidos beta-Amiloides/biosíntesis , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Encéfalo/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Tiazinas/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Administración Oral , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/química , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/uso terapéutico , Humanos , Masculino , Ratones , Ratones Transgénicos , Péptidos/metabolismo , Tiazinas/síntesis química , Tiazinas/uso terapéutico , Resultado del Tratamiento
18.
Rev. colomb. cienc. pecu ; 23(3): 336-348, jul.-sep. 2010. graf, tab
Artículo en Español | LILACS | ID: lil-636056

RESUMEN

El presente trabajo de investigación tiene como objetivo identificar la influencia del proceso de cocción y la temperatura de almacenamiento sobre la vida útil del jamón de cerdo, tajado y empacado. Se realizaron seis tratamientos, con tres temperaturas internas de cocción (72, 75, 78 °C) y dos temperaturas de almacenamiento (4 y 8 °C). Se elaboró un patrón absoluto cocido hasta una temperatura interna de 72 °C, sin tiempo de retención, con una vida útil establecida previamente de 26 días y un patrón relativo, elaborado bajo las mismas condiciones del patrón absoluto, almacenado a 0 °C. El estudio mostró que los recuentos de mesófilos, bacterias ácido lácticas y color, presentaron diferencia significativa (p<0.001), siendo el más estable el producto calentado hasta 75 °C, 5 minutos de retención y almacenamiento a 4 °C (75 °C - 5min - 4 °C). Respecto al contenido de bases volátiles nitrogenadas se encontró que ninguno de los tratamientos alcanzó niveles de degradación superiores a los establecidos por los reglamentos técnicos. Al incrementarse el periodo de almacenamiento, la dureza y la adhesividad instrumental presentaron tendencia al aumento, siendo el tratamiento 75 °C-5min-4 °C el que reportó mayor valor de dureza. Para todos los tratamientos se encontró que el pH disminuye y la sinéresis aumenta a medida que transcurre el periodo de almacenamiento.


Both, cooking and storage, can affect processed meat traits. In this study, six treatments were evaluated: three internal cooking temperatures (72, 75, 78 °C) and two storage temperatures (4 and 8 °C). Mesophilic counts, lactic acid bacteria and color differed (p<0.001). The product heated to 75 °C, 5 minutes of retention, and stored at 4 °C (75 °C - 5 min - 4 °C) was the most stable. Regarding the content of volatile nitrogen bases, none of the treatments reached degradation levels above the established by technical regulations. As the storage time increased, hardness and instrumental adhesiveness also tended to increase, with the 75 °C - 5 min - 4 °C treatment resulting in the highest hardness value. For all the treatments, pH diminished and syneresis increased as the storage time increased.


A presente pesquisa teve como objetivo identificar a influência do processo de cocção e temperatura de armazenamento sobre a vida de prateleira do presunto de suíno, fatiado e embalado. Foram feitos seis tratamentos, com três temperaturas internas de cocção (72, 75, 78 °C) e dois temperatura de armazenamento (4 e 8 °C). foi elaborado um padrão absoluto cozinhado ate atingir uma temperatura interna de 72 °C, sem tempo de retenção, com uma vida útil prevista previamente de 26 dias e um padrão relativo, elaborado nas mesmas condições do padrão absoluto, armazenado a 0 °C. Os resultados mostram que os valores de mesófilos, bactérias ácido lácticas e cor, apresentaram diferencias significativas (p<0.001), sendo o mais estável o produto esquentado ate 75 °C, 5 minutos de retenção e armazenamento a 4 °C (75 °C - 5 min - 4 °C). Respeito ao conteúdo das bases voláteis nitrogenadas foi encontrado que nenhum dos tratamentos alcanço níveis de degradação superiores a os aceitados pelas normas técnicas. Ao incrementar-se o período de armazenamento, a dureza e adesividade instrumental apresentaram tendência no aumento, sendo o tratamento 75 °C - 5 min - 4 °C que reportou maior valor de dureza. Para todos os tratamentos fui encontrado que o pH diminui e a sinéresis aumenta a o longo do período de armazenamento.

19.
Rev Med Chil ; 132(1): 75-80, 2004 Jan.
Artículo en Español | MEDLINE | ID: mdl-15379057

RESUMEN

We report a 26 year old female with Cushing's disease who became pregnant during the course of her disease. She was treated by transsphenoidal surgery during the second trimester of pregnancy, achieving resolution of hypercortisolism. She had a normal delivery at term, her offspring was healthy, and she had a normal lactation. Currently, five years after surgery, she is asymptomatic. According to our literature review, this patient is the fifth reported case of pituitary adenomectomy during gestation.


Asunto(s)
Adenoma/cirugía , Síndrome de Cushing/cirugía , Neoplasias Hipofisarias/cirugía , Complicaciones Neoplásicas del Embarazo/cirugía , Adenoma/complicaciones , Adulto , Síndrome de Cushing/etiología , Femenino , Humanos , Recién Nacido , Neoplasias Hipofisarias/complicaciones , Embarazo , Seno Esfenoidal/cirugía
20.
Medisan ; 12(4)oct.-dic. 2008. ilus, tab
Artículo en Español | LILACS | ID: lil-532484

RESUMEN

Se realizó un estudio descriptivo y transversal sobre la infestación por Aedes aegypti en el municipio de Santiago de Cuba durante el 2005 y primer trimestre del 2006, con vista a valorar el cumplimiento de las medidas antivectoriales diseñadas para enfrentar la reintroducción del dengue. Se constituyó un equipo multidisciplinario de la Unidad Municipal de Higiene y Epidemiología, el cual trazó una estrategia de transformación, basada en los principios de la aplicada en el área de salud del Policlínico Ramón López Peña y luego en el resto del territorio municipal. En el 2005 fueron identificados 36 024 focos, o sea, 14 306 más que en el 2004. El tratamiento de acción residual se aplicó en 15 por ciento del total de manzanas, con 74,4 por ciento de reducción de la infestación en 2 meses. En 10 semanas, el número de focos disminuyó en 88,9 por ciento y el índice de casas positivas descendió hasta 0,09 por ciento.


A descriptive and cross-sectional study on infestation by Aedes aegypti in Santiago de Cuba municipality was carried out during 2005 and first trimester of 2006, with the purpose of evaluating the execution of antivectorial measures designed to face the reintroduction of dengue. A multidisciplinary team of the Municipal Hygiene and Epidemiology Unit was constituted, which drew a strategy of transformation based on the principles of that applied in the health area of Ramón López Peña polyclinic and then in the rest of the municipal territory. In 2005, 36 024 focuses were identified, that is, 14 306 more than in 2004. The residual action treatment was applied in 15 percent of the total of blocks, with 74,4 percent of infestation decrease in 2 months. The number of focuses was reduced in 88,9percent and the rate of closed houses lowered to 0,09 percent in 10 weeks.


Asunto(s)
Humanos , Masculino , Femenino , Aedes , Enfermedades Transmisibles , Dengue , Control de Mosquitos , Atención Primaria de Salud , Estudios Transversales , Epidemiología Descriptiva
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA