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1.
Artículo en Inglés | MEDLINE | ID: mdl-36430001

RESUMEN

BACKGROUND: Discussion of the topic of noninvasive prenatal screening (NIPS) has become a standard part of Dutch maternity care practice. This means that pregnant women who are contemplating NIPS can receive counseling from their midwife or obstetrician. The aim of this study is to understand the communicative practices and decision-making principles regarding first-tier use of NIPS, as experienced by Dutch midwives. METHODS: Qualitative analysis of in-depth interviews with Dutch midwives (n = 10) exploring their conversations about NIPS counseling and decision making. RESULTS: Midwives value the autonomy of women in decisions on NIPS. They consider it a midwifery task to assess women's awareness of the risks and implications of using or not using this mode of screening. The optimal level of awareness may differ between women and midwives, creating novel challenges for informed decision making in midwifery communication. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Negotiating awareness about NIPS in individual women is a relatively new and complex midwifery task in need of counseling time and skill. NIPS practices call for a reflection on midwifery values in the context of integrated maternity care.


Asunto(s)
Servicios de Salud Materna , Partería , Pruebas Prenatales no Invasivas , Femenino , Humanos , Embarazo , Consejo , Negociación
2.
Scand J Rheumatol ; 50(3): 231-238, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33243053

RESUMEN

Objective: To investigate the relationship between the monocyte-to-high-density lipoprotein cholesterol ratio (MHR) and clinical manifestations in patients with systemic sclerosis (SSc).Method: This was a cross-sectional analysis of a cohort study comprising 111 female SSc patients recruited from a tertiary care rheumatology centre. We also assessed 222 age-matched female healthy controls. Serum MHR was measured in all study participants. Digital ulcer (DU) was defined as an active or healed ulceration, and the magnitude of skin fibrosis was determined according to the modified Rodnan skin score (mRSS).Results: The mean age and median disease duration in patients with SSc were 56.3 years and 98 months, respectively. The MHR in SSc patients was significantly higher than that in controls. DU was found in 35 patients (31.5%) with SSc (active in 12 and healed in 23), and the median mRSS was 8. SSc patients with DU had a significantly higher median MHR than those without (11.43 vs 7.62, p < 0.001), and MHR significantly positively correlated with mRSS (ρ = 0.289, p = 0.002). Multivariable logistic regression revealed that an elevated MHR was independently associated with increased risk of DU (odds ratio = 1.21; 95% confidence interval = 1.07-1.35; p = 0.002). In the multivariable linear regression analysis, higher MHR showed a significant association with increased log-transformed mRSS (unstandardized ß = 0.052, p = 0.003).Conclusion: Our findings suggest that the MHR could be serve as a potential biomarker of the risk of DU and advanced skin fibrosis in patients with SSc.


Asunto(s)
HDL-Colesterol/sangre , Fibrosis/sangre , Monocitos/metabolismo , Esclerodermia Sistémica/sangre , Úlcera Cutánea/sangre , Piel/patología , Biomarcadores/sangre , Estudios Transversales , Femenino , Fibrosis/patología , Humanos , Persona de Mediana Edad , Esclerodermia Sistémica/patología , Úlcera Cutánea/patología
3.
Z Rheumatol ; 79(4): 389-392, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32140801

RESUMEN

Rheumatoid arthritis (RA) is an inflammatory polyarthritis that typically affects the small joints but can also involve the manubriosternal joint (MSJ). Although cases of MSJ involvement in RA are rare, such cases present with chest pain, a mass-like lesion, and subluxation. These cases can also be diagnosed incidentally, while patients are asymptomatic. It is important to differentiate RA involving the MSJ from other diseases such as ankylosing spondylitis that can affect the MSJ. Several cases of RA affecting the MSJ have been reported in Western countries, but none have been reported to date in Asia, especially with disease activity of RA. Here, we report a case of RA in the MSJ that was confirmed by imaging and histological investigation in a middle-aged Asian woman.


Asunto(s)
Artritis Reumatoide , Esternón , Asia , Biopsia , Femenino , Humanos , Persona de Mediana Edad , Esternón/patología
4.
Lupus ; 27(5): 753-761, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29157178

RESUMEN

We aimed to analyze compliance and persistence with hydroxychloroquine (HCQ) in real practice and identify risk factors for poor adherence in South Korean patients with systemic lupus erythematosus (SLE). This retrospective longitudinal study evaluated 235 SLE patients in whom oral HCQ was newly started from 2002 to 2016 at a tertiary hospital in South Korea. Compliance was assessed using one-year medication possession ratio (MPR) and non-compliance was defined as a one-year MPR < 0.8. Persistence was determined as the time from HCQ treatment initiation to discontinuation without interruption for ≥56 days. The mean one-year MPR of HCQ was 0.88 and the frequency of non-compliance was 19.9%. During the study period, 115 (48.9%) patients discontinued HCQ and forgetfulness and/or carelessness (73%) were the most common reason for HCQ non-persistence, followed by adverse events (10.4%), unknown factors (10.4%), and pregnancy (6.1%). Median duration until HCQ discontinuation was 55.1 months and the one-year persistence rate to HCQ was 0.8. SLE Disease Activity Index 2000 (SLEDAI-2K) < 6 was a significant risk factor for non-compliance (OR = 2.98, p = 0.001) and non-persistence (HR = 1.55, p = 0.046) with HCQ after adjusting confounding factors. However, HCQ adherence was not associated with the dose of HCQ or concomitant immunosuppressive medications. Our data showed that overall adherence to HCQ in SLE patients was suboptimal in real practice and SLEDAI-2K score < 6 was a risk factor for poor adherence, suggesting the need to improve adherence with HCQ treatment in SLE patients, especially in those with low disease activity.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Hidroxicloroquina/administración & dosificación , Inmunosupresores/administración & dosificación , Lupus Eritematoso Sistémico/tratamiento farmacológico , Cumplimiento de la Medicación , Administración Oral , Adolescente , Adulto , Anciano , Pueblo Asiatico/psicología , Niño , Esquema de Medicación , Femenino , Humanos , Hidroxicloroquina/efectos adversos , Inmunosupresores/efectos adversos , Estudios Longitudinales , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/etnología , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Centros de Atención Terciaria , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
5.
J Periodontal Res ; 51(4): 529-39, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26548452

RESUMEN

BACKGROUND AND OBJECTIVE: Although overexpression of the nuclear factor κB inhibitory and ubiquitin-editing enzyme A20 is thought to be involved in the pathogenesis of inflammatory diseases, its function in periodontal disease remains unknown. The aims of the present study were to evaluate A20 expression in patients with periodontitis and to study the effects of A20 overexpression, using a recombinant adenovirus encoding A20 (Ad-A20), on the inflammatory response and on osteoclastic differentiation in lipopolysaccharide (LPS)- and nicotine-stimulated human periodontal ligament cells (hPDLCs). MATERIAL AND METHODS: The concentration of prostaglandin E2 was measured by radioimmunoassay. Reverse transcription-polymerase chain reactions and western blot analyses were used to measure mRNA and protein levels, respectively. Osteoclastic differentiation was assessed in mouse bone marrow-derived macrophages using conditioned medium from LPS- and nicotine-treated hPDLCs. RESULTS: A20 was upregulated in the gingival tissues and neutrophils from patients with periodontitis and in LPS- and nicotine-exposed hPDLCs. Pretreatment with A20 overexpression by Ad-A20 markedly attenuated LPS- and nicotine-induced production of prostaglandin E2 , as well as expression of cyclooxygenase-2 and proinflammatory cytokines. Moreover, A20 overexpression inhibited the number and size of tartrate-resistant acid phosphatase-stained osteoclasts, and downregulated osteoclast-specific gene expression. LPS- and nicotine-induced p38 phosphorylation and nuclear factor κB activation were blocked by Ad-A20. Ad-A20 inhibited the effects of nicotine and LPS on the activation of pan-protein kinase C, Akt, GSK-3ß and protein kinase Cα. CONCLUSIONS: This study is the first to demonstrate that A20 overexpression has anti-inflammatory effects and blocks osteoclastic differentiation in a nicotine- and LPS-stimulated hPDLC model. Thus, A20 overexpression may be a potential therapeutic target in inflammatory bone loss diseases, such as periodontal disease.


Asunto(s)
Antiinflamatorios/farmacología , Encía/metabolismo , Osteoclastos/efectos de los fármacos , Ligamento Periodontal/efectos de los fármacos , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/farmacología , Animales , Antiinflamatorios/metabolismo , Western Blotting , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Dinoprostona/metabolismo , Perfilación de la Expresión Génica , Humanos , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Ratones , FN-kappa B/antagonistas & inhibidores , Nicotina/farmacología , Ligamento Periodontal/citología , Porphyromonas gingivalis , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba
6.
Oral Dis ; 21(6): 785-91, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25970794

RESUMEN

OBJECTIVES: The aim of this study was to determine the clinical efficacy of the newly developed OrthoMTA and RetroMTA, compared to conventionally used ProRoot MTA, for pulpotomy in primary teeth. MATERIAL AND METHODS: In this randomized clinical trial, 151 molars from 102 children, who met the inclusion criteria and were 3-10 years old, were enrolled. Ultimately, 143 teeth were divided in a randomized, single-blind manner into three groups according to the planned treatment: RetroMTA (n = 49 teeth), OrthoMTA (n = 47 teeth) or ProRoot MTA (n = 47 teeth). Clinical and radiographic follow-up examinations were conducted at 3, 6 and 12 months postoperatively. RESULTS: By the end of the study period, 109 teeth were evaluated at 12 months. The radiographic success rates in these three groups were 100%, 94.7% and 94.7%, respectively; the corresponding clinical success rates were 100%, 97.4% and 100%. The Kaplan-Meier survival function curves relative to clinical and radiographic cumulative survival rates did not differ significantly between the three groups. CONCLUSIONS: The success rates of RetroMTA, OrthoMTA and ProRoot MTA are indistinguishable, indicating that pulpotomy can be carried out successfully in primary molars with the newly developed materials.


Asunto(s)
Compuestos de Aluminio/uso terapéutico , Compuestos de Calcio/uso terapéutico , Óxidos/uso terapéutico , Materiales de Recubrimiento Pulpar y Pulpectomía/uso terapéutico , Pulpotomía , Silicatos/uso terapéutico , Diente Primario , Niño , Preescolar , Combinación de Medicamentos , Femenino , Humanos , Masculino , Método Simple Ciego , Diente Primario/diagnóstico por imagen , Resultado del Tratamiento
7.
Rev Sci Instrum ; 85(11): 116102, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430151

RESUMEN

This Note presents a nonlinear device model for organic light emitting diodes (OLEDs), which can describe dynamic and static characteristics of OLEDs consistently. The parameters of the proposed model are estimated by using a particle swarm optimization algorithm. Some of the resulting parameters relate with physical characteristics of OLEDs. With only one set of experiments leading to a time response of an OLED device, this nonlinear model, together with all the parameters, is obtained, which can be a big advantage for the fast quality control of the OLEDs.

8.
J Dent Res ; 93(7): 678-84, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24820666

RESUMEN

The precise regulation of odontoblast differentiation and osteoclastogenic cytokine expression in human dental pulp cells (HDPCs) is crucial for the pathology of bacteria-related pulpitis. Although the up-regulation of nucleotide-binding oligomerization domain-containing protein 2 (NOD2) has been reported in inflamed human dental pulps, the role of NOD2 in the differentiation of HDPCs remains unclear. Here, we show the involvement of NOD2 in odontoblast differentiation together with osteoclastogenic cytokine expression in HDPCs. Treatment with muramyl dipeptide (MDP), a known NOD2-agonist, significantly inhibited odontoblast differentiation of HDPCs, as revealed by reduced ALP activity, osteoblast/odontoblast marker expression, and mineralized nodule formation. Importantly, the forced down-regulation of NOD2 by small interfering RNA (siRNA) recovered MDP-down-regulated odontoblast differentiation. MDP-elicited suppression of odontoblast differentiation resulted from the increased expression of MKP-1 protein and the subsequent decline of MAPKs phosphorylation, which is a prerequisite for odontoblast differentiation. Furthermore, we found that MDP treatment elevated the expression of osteoclastogenic cytokines in HDPCs, which was also reversed by NOD2 silencing. Analysis of these data, taken together, suggests that the regulation of NOD2 expression upon MDP challenge might serve as an intrinsic mechanism that underlies the hindered dentin formation and accelerated dentin resorption in bacterial infection-mediated pulpitis.


Asunto(s)
Proteína Adaptadora de Señalización NOD2/fisiología , Odontoblastos/fisiología , Ligando RANK/análisis , Acetilmuramil-Alanil-Isoglutamina/farmacología , Adyuvantes Inmunológicos/farmacología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular , Citocinas/efectos de los fármacos , Pulpa Dental/citología , Fosfatasa 1 de Especificidad Dual/efectos de los fármacos , Silenciador del Gen , Humanos , Factor Estimulante de Colonias de Macrófagos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Proteína Adaptadora de Señalización NOD2/agonistas , Proteína Adaptadora de Señalización NOD2/genética , Odontoblastos/efectos de los fármacos , Osteoclastos/fisiología , Osteoprotegerina/efectos de los fármacos , Ligando RANK/efectos de los fármacos , ARN Interferente Pequeño/genética
9.
Acta Physiol (Oxf) ; 207(2): 397-404, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23227957

RESUMEN

AIM: Lamotrigine is a neuroprotective agent that is used clinically for the treatment of seizures and neuropathic pain. A significant volume of literature has reported that lamotrigine exerts analgesic effect by blocking Ca(2+) channels. However, little is known regarding the effect of lamotrigine on the intracellular Ca(2+) concentration ([Ca(2+)](i)). The aim of this study was to determine whether lamotrigine modulates [Ca(2+)](i) in sensory neurones. METHODS: Lamotrigine-induced changes in [Ca(2+)](i) were measured in mouse dorsal root ganglion (DRG) neurones using the Ca(2+)-sensitive fluorescent indicator Fluo 3-AM and a confocal laser scanning microscope. Ca(2+)/calmodulin-dependent kinase II (CaMKII) activation was assessed by the fluorescence intensity using immunocytochemical procedures. RESULTS: Treatment with 1, 10, 30 or 100 µM lamotrigine transiently increased [Ca(2+)](i) in DRG neurones in a dose-dependent manner. Treatment with 100 µM lamotrigine induced a significant (threefold) increase in the Ca(2+) peak in the presence or absence of extracellular Ca(2+). The lamotrigine-induced Ca(2+) increase was abolished or decreased by the treatment with a specific PLC inhibitor (U73122), IP3R antagonist (xestospongin C) or RyR antagonist (dantrolene). In some cells, treatment with 100 µM lamotrigine caused a transient Ca(2+) increase, and the Ca(2+) levels quickly fell to below the basal Ca(2+) level observed prior to lamotrigine application. The decrease in basal Ca(2+) levels was blocked by the treatment with a CaMKII inhibitor (KN93). Immunocytochemical analysis indicated that lamotrigine treatment increased the expression of phosphorylated CaMKII in DRG neurones. CONCLUSION: Treatment with lamotrigine increased [Ca(2+)](i) apparently as a result of Ca(2+) release from intracellular stores and CaMKII activity.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Calcio/metabolismo , Neuronas/efectos de los fármacos , Triazinas/farmacología , Animales , Activación Enzimática/efectos de los fármacos , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/enzimología , Inmunohistoquímica , Lamotrigina , Masculino , Ratones , Ratones Endogámicos ICR , Microscopía Confocal , Neuronas/metabolismo
10.
PLoS One ; 7(7): e40057, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22808090

RESUMEN

Stimulation of either GABA(A) or GABA(B) receptors within the nucleus accumbens shell strongly enhances food intake in rats. However the effects of subtype-selective stimulation of GABA receptors on instrumental responses for food reward are less well characterized. Here we contrast the effects of the GABA(A) receptor agonist muscimol and GABA(B) receptor agonist baclofen on instrumental responding for food using a second order reinforcement schedule. Bilateral intra-accumbens administration of baclofen (220-440 pmol) stimulated responding but a higher dose (660 pmol) induced stereotyped oral behaviour that interfered with responding. Baclofen (220-660 pmol) also stimulated intake of freely available chow. Muscimol (220-660 pmol) was without effect on responding for food on this schedule but did stimulate intake of freely available chow. Unilateral administration of either baclofen or muscimol (220 pmol) induced similar patterns of c-fos immunoreactivity in several hypothalamic sites but differed in its induction in the central nucleus of the amygdala. We conclude that stimulation of GABA(A) or GABA(B) receptors in the nucleus accumbens shell of rats produces clearly distinguishable effects on operant responding for food.


Asunto(s)
Amígdala del Cerebelo/efectos de los fármacos , Baclofeno/farmacología , Ingestión de Alimentos/efectos de los fármacos , Agonistas del GABA/farmacología , Muscimol/farmacología , Núcleo Accumbens/efectos de los fármacos , Amígdala del Cerebelo/fisiología , Animales , Regulación del Apetito/efectos de los fármacos , Mapeo Encefálico , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/fisiología , Inyecciones Intraventriculares , Masculino , Núcleo Accumbens/fisiología , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Ratas , Ratas Endogámicas , Receptores de GABA-A/metabolismo , Receptores de GABA-B/metabolismo , Esquema de Refuerzo , Recompensa
11.
Clin Anat ; 25(2): 182-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21544876

RESUMEN

The recent introduction of cone-beam computed tomography (CBCT) into the medical field has allowed the nondestructive investigation of internal structures at relatively low cost and radiation exposure. The accuracy of CBCT in both two and three dimensions has been demonstrated, and CBCT has been used successfully for craniofacial anatomy. Knowing the anatomical structure of deciduous teeth is essential for clinical dentistry. However, the root structure of deciduous teeth is rarely reported because of the scarcity of intact deciduous teeth without root resorption. The aim of this study was to evaluate the intact root form of deciduous teeth using CBCT. Data from 38 young children was analyzed using an image-analyzing program. The degree of buccal dilacerations was 26.3° for deciduous maxillary central incisors (DMA), 16.5° for deciduous maxillary lateral incisors (DMB), and 17.5° for deciduous maxillary canines (DMC) in about half of the root length. The crown-to-root ratios were 0.52 for DMA, 0.48 for DMB, and 0.52 for DMC. These data will be helpful for understanding the development of dentition, and for clinical dentistry.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Maxilar/anatomía & histología , Diente Primario , Diente Primario/anatomía & histología , Preescolar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Maxilar/diagnóstico por imagen , Diente Primario/diagnóstico por imagen
12.
Acta Physiol (Oxf) ; 204(4): 513-24, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21910834

RESUMEN

AIM: Many kinds of K(+) channels are expressed in a variety of cells, including cancer cells. However, only a small amount of research has explored the relationship between voltage-independent K(+) channels and breast cancer. This study was performed to investigate whether changes in two-pore domain K(+) (K(2P) ) channel expression levels are related to the migration of human breast cancer cells. METHODS: K(2P) channel gene/protein expression levels were compared between MCF-7 (a non-invasive cell) and MDA-MB-231 (an invasive cell) using reverse transcriptase (RT)-polymerase chain reaction (PCR), real-time PCR, Western blotting and immunocytochemistry. The relationship between K(2P) channel expression level and cell migration was analysed using gene overexpression and knock-down techniques. Functional expression of TASK-3 in MCF-7 and MDA-MB-231 cells was recorded using patch-clamp technique. RESULTS: Of K(2P) channels, TASK-3 mRNA and protein were highly expressed in MCF-7 cells compared with those in MDA-MB-231 cells. Overexpression of TASK-3 in breast cancer cells reduced migration and invasion, whereas silencing of TASK-3 increased the migration and invasion. The TASK-3 expression level was decreased by phorbol myristate acetate (PMA), a PKC activator. PMA also enhanced the cell migration in MDA-MB-231 cells. CONCLUSION: These results show that an increase in TASK-3 expression levels, which could be modulated by PKC activation, reduces cell migration/invasion in breast cancer cells and suggest that modulation of TASK-3 expression may regulate metastasis of breast cancer cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Movimiento Celular/genética , Invasividad Neoplásica/genética , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Western Blotting , Neoplasias de la Mama/genética , Línea Celular Tumoral , Activación Enzimática/fisiología , Femenino , Humanos , Inmunohistoquímica , Técnicas de Placa-Clamp , Canales de Potasio de Dominio Poro en Tándem/genética , Proteína Quinasa C/metabolismo , ARN Interferente Pequeño , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Regulación hacia Arriba
13.
J Nanosci Nanotechnol ; 10(5): 3385-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20358962

RESUMEN

The noble gas sensor using multiple ZnO nanorods was fabricated with CMOS compatible process and sol-gel growth method on selective area and gas response characteristics to NO2 gas of the sensor device were investigated. We confirmed the sensors had high sensitive response denoted by the sensitivity of several tens for NO2 gas sensing and also showed pretty low power consumption close to 20 mW even though the recovery of resistance come up to almost the initial value.

14.
J Nanosci Nanotechnol ; 8(9): 4698-701, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19049088

RESUMEN

Vertically well-aligned high quality ZnO nanowires were grown on GaN epilayer on c-plane sapphire via a vapor-liquid-solid (VLS) process by introducing an Au thin film (3 nm) as a catalyst. ZnO single nanowire device was ingenuously fabricated by combining conventional optical lithography and high resolution electron beam lithography and its current-voltage characteristics were measured with doing the post process to acquire reproducible performance as a chemical gas sensor. And its temperature dependent current-voltage characteristics were measured to investigate temperature dependant electrical transport. The ZnO nanowire device showed slightly non-ohmic current-voltage characteristics which may be due to back-to-back configuration of the diodes with the insulating contact barriers and showed an relatively small activation energy of 0.2 eV. To test our device as a chemical sensor, the NO2 gas response was reported at the elevated temperature.


Asunto(s)
Técnicas Biosensibles/instrumentación , Nanotecnología/instrumentación , Nanocables/química , Óxido de Zinc/química , Cristalización , Electricidad , Electroquímica/métodos , Microscopía Electrónica de Rastreo , Modelos Químicos , Nanotubos/química , Óptica y Fotónica , Semiconductores , Temperatura , Difracción de Rayos X , Zinc/química
15.
Environ Toxicol Chem ; 27(2): 404-12, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18348632

RESUMEN

The Organisation for Economic Cooperation and Development (OECD) is currently validating a short-term fish screening protocol for endocrine disrupters (estrogens, androgens, and their antagonists and aromatase inhibitors), using three core species: fathead minnow, Japanese medaka, and zebrafish. The main endpoints proposed for the first phase of validation of the screen are vitellogenin (VTG) concentration, gross morphology (secondary sexual characteristics and gonado-somatic index), and gonadal histopathology. A similar protocol is concurrently being developed in the United Kingdom using the three-spined stickleback, with identical endpoints to those for the core species and, in addition, a unique androgen-specific endpoint in the form of spiggin (glue protein) induction. To assess the suitability of this species for inclusion in the OECD protocol alongside the core species, an intercalibration was conducted using 17beta-estradiol (a natural estrogen) and trenbolone (a synthetic androgen), thus mimicking a previous intercalibration with the core species. All three participating laboratories detected statistically significant increases in VTG in males after 14 d exposure to nominal concentrations of 100 ng/L 17beta-estradiol and statistically significant increases in spiggin in females after 14 d exposure to nominal concentrations of 5,000 ng/L trenbolone. The stickleback screen is reliable, possessing both relevant and reproducible endpoints for the detection of potent estrogens and androgens. Further work is underway to assess the relevance and suitability of the screen for weakly acting estrogens, anti-androgens, and aromatase inhibitors.


Asunto(s)
Bioensayo/métodos , Disruptores Endocrinos/farmacología , Estradiol/farmacología , Smegmamorpha/fisiología , Acetato de Trembolona/farmacología , Animales , Relación Dosis-Respuesta a Droga , Monitoreo del Ambiente/métodos , Femenino , Proteínas de Peces/metabolismo , Masculino , Ovario/efectos de los fármacos , Ovario/fisiología , Reproducibilidad de los Resultados , Testículo/efectos de los fármacos , Testículo/fisiología , Vitelogeninas/metabolismo
16.
Neurosci Biobehav Rev ; 31(3): 396-412, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17182101

RESUMEN

Reactions to stress vary between individuals, and physiological and behavioral responses tend to be associated in distinct suites of correlated traits, often termed stress-coping styles. In mammals, individuals exhibiting divergent stress-coping styles also appear to exhibit intrinsic differences in cognitive processing. A connection between physiology, behavior, and cognition was also recently demonstrated in strains of rainbow trout (Oncorhynchus mykiss) selected for consistently high or low cortisol responses to stress. The low-responsive (LR) strain display longer retention of a conditioned response, and tend to show proactive behaviors such as enhanced aggression, social dominance, and rapid resumption of feed intake after stress. Differences in brain monoamine neurochemistry have also been reported in these lines. In comparative studies, experiments with the lizard Anolis carolinensis reveal connections between monoaminergic activity in limbic structures, proactive behavior in novel environments, and the establishment of social status via agonistic behavior. Together these observations suggest that within-species diversity of physiological, behavioral and cognitive correlates of stress responsiveness is maintained by natural selection throughout the vertebrate sub-phylum.


Asunto(s)
Adaptación Psicológica/fisiología , Conducta Animal/fisiología , Cognición/fisiología , Glucocorticoides/fisiología , Estrés Psicológico/psicología , Animales , Monoaminas Biogénicas/fisiología , Evolución Biológica , Encéfalo/fisiología , Individualidad , Lagartos , Oncorhynchus mykiss , Predominio Social
17.
J Appl Microbiol ; 101(3): 698-710, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16907820

RESUMEN

AIMS: To characterize bacterial populations and their activities within a microbial fuel cell (MFC), using cultivation-independent and cultivation approaches. METHODS AND RESULTS: Electron microscopic observations showed that the fuel cell electrode had a microbial biofilm attached to its surface with loosely associated microbial clumps. Bacterial 16S rRNA gene libraries were constructed and analysed from each of four compartments within the fuel cell: the planktonic community; the membrane biofilm; bacterial clumps (BC) and the anode biofilm. Results showed that the bacterial community structure varied significantly between these compartments. It was observed that Gammaproteobacteria phylotypes were present at higher numbers within libraries from the BC and electrode biofilm compared with other parts of the fuel cell. Community structure of the MFC determined by analyses of bacterial 16S rRNA gene libraries and anaerobic cultivation showed excellent agreement with community profiles from denaturing gradient gel electrophoresis (DGGE) analysis. CONCLUSIONS: Members of the family Enterobacteriaceae, such as Klebsiella sp. and Enterobacter sp. and other Gammaproteobacteria with Fe(III)-reducing and electrochemical activity had a significant potential for energy generation in this system. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has shown that electrochemically active bacteria can be enriched using an electrochemical fuel cell.


Asunto(s)
Bacterias/genética , Fenómenos Fisiológicos Bacterianos , Electroquímica/instrumentación , Anaerobiosis , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Biopelículas , Recuento de Colonia Microbiana , Electroforesis en Gel de Poliacrilamida/métodos , Compuestos Férricos/metabolismo , Genes Bacterianos/genética , Microscopía Electrónica/métodos , Filogenia , Reacción en Cadena de la Polimerasa/métodos , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ARN/métodos
18.
J Appl Microbiol ; 99(4): 978-87, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16162251

RESUMEN

AIMS: The isolation and identification of a glucose-oxidizing Fe(III)-reducing bacteria (FRB) with electrochemical activity from an anoxic environment, and characterization of the role of Fe(III) in its metabolism. METHODS AND RESULTS: A Gram-positive (Firmicutes), nonmotile, coccoid and facultative anaerobic FRB was isolated based on its ability to reduce Fe(III). Using the Vitek Gram-positive identification card kit and 16S rRNA gene sequence analysis, the isolate was identified as Enterococcus gallinarum, designated strain MG25. On glucose this isolate produced lactate plus small amounts of acetate, formate and CO2 and its growth rates were similar in the presence and absence of Fe(O)OH. These results suggest that MG25 can couple glucose oxidation to Fe(III) reduction, but without conservation of energy to support growth. Cyclic voltammetry showed that strain MG25 was electrochemically active. CONCLUSIONS: An electrochemically active and FRB, E. gallinarum MG25, was isolated from submerged soil. Fe(III) is used in the bacterial metabolism as an electron sink. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report concerning the electrochemical activity of glucose-oxidizing FRB, E. gallinarum. This organism and others like it could be used as new biocatalysts to improve the performance of a mediator-less microbial fuel cell.


Asunto(s)
Enterococcus/metabolismo , Hierro/metabolismo , Microbiología del Suelo , Medios de Cultivo , Electroquímica , Enterococcus/aislamiento & purificación , Enterococcus/ultraestructura , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Microscopía Electrónica/métodos , Oxidación-Reducción , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Temperatura
19.
Horm Behav ; 48(5): 537-44, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15907328

RESUMEN

The aim of this study was to establish whether two lines of rainbow trout divergent for their plasma cortisol response to a standardized stressor would show consistent differences in their behavioural response to a range of challenging situations. Our results show that the high- and low-responding (HR and LR) lines of rainbow trout did not differ in the aggression shown towards an intruder or in their response to the introduction of a novel object to their home environment. However, there was a difference in behaviour between the two selection lines when they were exposed to two unfamiliar environments. These results suggest that the behaviour of the HR and LR fish differs when they are challenged in unfamiliar environments, while their behaviour does not differ when they are challenged in their home environment. These observations are in agreement with studies on mammals that show that individuals with reactive coping styles perform similarly to proactive animals when they are challenged in a familiar environment, while they show different behaviour when they are challenged in unfamiliar environments. Thus, these results provide further evidence that the HR and LR selection lines of rainbow trout exemplify the two different coping styles described in mammals.


Asunto(s)
Conducta Animal/fisiología , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/fisiología , Estrés Psicológico/genética , Estrés Psicológico/psicología , Agresión , Animales , Femenino , Hidrocortisona/sangre , Masculino , Restricción Física , Especificidad de la Especie
20.
Appl Microbiol Biotechnol ; 63(6): 672-81, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12908088

RESUMEN

A fuel cell was used to enrich a microbial consortium generating electricity, using organic wastewater as the fuel. Within 30 days of enrichment the maximum current of 0.2 mA was generated with a resistance of 1 kOhms. Current generation was coupled to a fall in chemical oxygen demand from over 1,700 mg l(-1) down to 50 mg l(-1). Denaturing gradient gel electrophoresis showed a different microbial population in the enriched electrode from that in the sludge used as the inoculum. Electron microscopic observation showed a biofilm on the electrode surface and microbial clumps. Nanobacteria-like particles were present on the biofilm surface. Metabolic inhibitors and electron acceptors inhibited the current generation. 16S ribosomal RNA gene analysis showed a diverse bacterial population in the enrichment culture. These findings demonstrate that an electricity-generating microbial consortium can be enriched using a fuel cell and that the electrochemical activity is a form of anaerobic electron transfer.


Asunto(s)
Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Fuentes de Energía Bioeléctrica , Electricidad , Compuestos Orgánicos/metabolismo , Aguas del Alcantarillado/microbiología , Bacterias/metabolismo , Bacterias/ultraestructura , Biopelículas/crecimiento & desarrollo , Catálisis , ADN Bacteriano/análisis , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Ribosómico/análisis , ADN Ribosómico/química , ADN Ribosómico/aislamiento & purificación , Electroquímica , Electrodos , Transporte de Electrón/fisiología , Electroforesis en Gel de Poliacrilamida , Microbiología Ambiental , Residuos Industriales , Datos de Secuencia Molecular , Oxidación-Reducción , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Eliminación de Residuos Líquidos/métodos , Microbiología del Agua
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