Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acid family of compounds. Due to the presence of strong carbon–fluorine bonds, it is practically nonbiodegradable and highly persistent ...in the environment. PFOA has been detected in the follicular fluid of women, and positively associated with reduced fecundability and infertility. However, there are no reports concerning the experimental evaluation of PFOA on oocyte toxicity in mammals. The aim of the present study was to determine if PFOA is able to induce oxidative stress in fetal ovaries and cause apoptosis in oocytes in vitro. In addition, since inhibition of the gap junction intercellular communication (GJIC) by PFOA has been demonstrated in liver cells in vivo and in vitro, the effect of PFOA on the GJIC between the oocyte and its supportive cumulus cells was studied. Results show that PFOA induced oocyte apoptosis and necrosis in vitro (medium lethal concentration, LC50 = 112.8 μM), as evaluated with Annexin‐V‐Alexa 508 in combination with BOBO‐1 staining. Reactive oxygen species (ROS) levels, as assessed by DCFH‐DA, increased significantly in fetal ovaries exposed to ¼ LC50 (28.2 μM, a noncytotoxic and relevant occupational exposure concentration) and LC50 PFOA ex vivo. This perfluorinated compound also caused the blockage of GJIC in cumulus cells‐oocyte complexes (COCs) obtained from female mice exposed in vivo, as evaluated by calcein transfer from cumulus cells to the oocyte. The ability of PFOA of disrupting the GJIC in COCs, generating ROS in the fetal ovary and causing apoptosis and necrosis in mammal's oocytes, might account for the reported association between increasing maternal plasma concentrations of PFOA with reduced fertility in women.
Risk factors for venous thromboembolism in cancer vary between tumours. Leucocytosis, thrombocytosis, tumour histology and vascular compression may drive thrombosis in ovarian cancer. Thrombosis ...developed in 13.4% of our patients. Higher median leucocyte, neutrophil and monocyte counts were related to thrombosis. Thrombocytosis >350 × 109/L was frequent (63.8%), but not predictive of thrombosis. Identification of prothrombotic biomarkers may help personalise preventive treatments.
In this work, the preparation of dense blended membranes, from blends of poly(vinylidene fluoride) (PVDF), poly(ether sulfone) (PES) and polyethyleneimine (PEI) or Fumion®, with possible applications ...in alkaline fuel cell (AEMFC) is reported. The blended PEI/Fumion® membranes were prepared under a controlled air atmosphere by a solvent evaporation method, and were characterized regarding water uptake, swelling ratio, thermogravimetric analysis (TGA), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), ion exchange capacity (IEC), OH− conductivity and novel hydroxide ion exchange rate (HIER), which is related to the mass transport capacity of the OH− ions through the membrane. The effect of the chemical composition on its morphological and anion exchange properties was evaluated. It was expected that the usage of a commercial ionomer Fumion®, in the blended membranes would result in better features in the electrical/ionic conductivity behaviour. However, two of the membranes containing PEI exhibited a higher HIER and OH− conductivity than Fumion® membranes, and were excellent option for potential applications in AEMFC, considering their performance and the cost of Fumion®-based membranes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The involvement of both cyclooxygenase (COX) isoforms in regulating renal function is well known but their interactions with other regulatory mechanisms, such as angiotensin II (Ang II) and nitric ...oxide (NO), are not well defined. This study has evaluated the relative contribution of both COX isoforms in regulating renal function when NO synthesis is reduced with and without a simultaneous increment in Ang II levels. The renal responses to a nonselective (meclofenamate) or a selective COX2 (nimesulide) inhibitor were examined in dogs pretreated with L-NAME with or without an intrarenal Ang II infusion. Meclofenamate induced a greater (P < 0.05) renal vasoconstriction than nimesulide in dogs pretreated with L-NAME. This vasoconstriction seems to be Ang II-dependent because it was reduced (P < 0.05) by captopril administration. Meclofenamate also induced a greater (P < 0.05) renal vasoconstriction than that elicited by nimesulide in dogs with reduced NO synthesis and elevated Ang II levels. The renal vasoconstriction induced by nimesulide but not that elicited by meclofenamate in dogs pretreated with L-NAME and Ang II, decreased (P < 0.05) during an extracellular volume expansion. These results demonstrate that the nonselective COX inhibition induces a greater renal vasoconstriction than that elicited by the selective COX2 inhibition when NO synthesis is reduced, and when NO synthesis is reduced and Ang II levels are elevated.
Objetivo: describir la percepción que tienen 201 enfermeros en relación a la Seguridad del Paciente (SP) en sus centros, valorar cuáles son los puntos fuertes y las áreas de mejora en los Distritos ...Sanitarios de la provincia de Almería.Metodología: Se ha utilizado el cuestionario denominado MOSPSC (Medical Office Survey on Patient Safety Culture), traducido, adaptado y validado para profesionales españoles de Atención Primaria. A través del programa estadístico SPSS, se calculó la media y el intervalo de confianza al 95% de cada una de las dimensiones del cuestionario.Resultados: se observa una percepción positiva de la SP en casi todas las dimensiones, a excepción de la “Comunicación sobre el error”, el “Seguimiento de la atención a los pacientes”, la “Comunicación franca” y el “Ritmo y Carga de trabajo”. Uno de los puntos fuertes de los enfermeros es el “trabajo en equipo”.Conclusiones: Los resultados de esta investigación también han destacado “el intercambio de información con otros equipos”; en cambio, entre las áreas de mejora que deberían tenerse en cuenta se halla, “la Comunicación franca y sobre el error”. Estos resultados deberían ayudar a evaluar la importancia de la SP en las organizaciones, para dialogar sobre los errores y crear un clima de aprendizaje y deseo de mejora en los profesionales que repercuta en la calidad de la atención ofrecida a los usuarios.
Adolescents need sexual and reproductive health services but little is known about quality-of-care in lower- and middle-income countries where most of the world's adolescents reside. Quality-of-care ...has important implications as lower quality may be linked to higher unplanned pregnancy and sexually transmitted infection rates. This study sought to generate evidence about quality-of-care in public sexual and reproductive health services for adolescents.
This cross-sectional study had a complex, probabilistic, stratified sampling design, representative at the national, regional and rural/urban level in Mexico, collecting provider questionnaires at 505 primary care units in 2012. A sexual and reproductive quality-of-healthcare index was defined and multinomial logistic regression was utilized in 2015.
At the national level 13.9% (95%CI: 6.9-26.0) of healthcare units provide low quality, 68.6% (95%CI: 58.4-77.3) medium quality and 17.5% (95%CI: 11.9-25.0) high quality reproductive healthcare services to adolescents. Urban or metropolitan primary care units were at least 10 times more likely to provide high quality care than those in rural areas. Units with a space specifically for counseling adolescents were at least 8 times more likely to provide high quality care. Ministry of Health clinics provided the lowest quality of service, while those from Social Security for the Underserved provided the best.
The study indicates higher quality sexual and reproductive healthcare services are needed. In Mexico and other middle- to low-income countries where quality-of-care has been shown to be a problem, incorporating adolescent-friendly, gender-equity and rights-based perspectives could contribute to improvement. Setting and disseminating standards for care in guidelines and providing tools such as algorithms could help healthcare personnel provide higher quality care.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introducción: El consumo de alcohol y tabaco son un problema de salud pública a nivel mundial que afecta a adolescentes y jóvenes. En México ocupa el décimo lugar con un consumo de 7.2 litros per ...cápita de alcohol y aproximadamente 14.9 millones de mexicanos son fumadores actualmente. Objetivo: Analizar la relación de percepción de riesgo y consumo de alcohol y tabaco en estudiantes universitarios de ciencias de la salud de una universidad pública en Tabasco, México. Metodología: Estudio descriptivo correlacional, en una muestra de 601 estudiantes seleccionados por muestreo probabilístico estratificado. Con criterios de selección: estar inscrito en el programa de enfermería, medicina u odontología, se eliminaron instrumentos incompletos o quien abandonó el estudio. Se aplicó cédula de datos personales y prevalencia de consumo de alcohol y tabaco, cuestionario de percepción de riesgo hacia el consumo de drogas lícitas y prueba Audit, garantizando anonimato, confidencialidad de datos y derecho de negarse a participar. Resultados: La media de consumo fue 3.6 en bebidas alcohólicas y 2.5 cigarrillos por ocasión. Existió relación negativa estadística significativa entre la percepción de riesgo con cantidad de cigarrillos consumidos con p<.05 y consumo de alcohol con p<.01. Conclusiones: El consumo de alcohol y tabaco se encuentra presente en los estudiantes universitarios de ciencias de la salud, por ello, se deben establecer intervenciones de enfermería sobre la percepción del riesgo del consumo para impactar en el fenómeno de las adicciones.
1 Department of Physiology, University of Murcia School of
Medicine, E-30100 Murcia; 2 Fundación Jiménez
Díaz, E-28040 Madrid; and 3 Department of Medical
Sciences, University of Castilla-La ...Mancha, E-02071 Albacete,
Spain
The aim of this study was to
assess the effects of acute or prolonged increases of ANG II on nitric
oxide synthase (NOS) activities and protein expression in mesenteric
resistance vessels, left ventricle, renal cortex, and renal medulla.
The response of NOS activities to ANG II is compared with that induced
by phenylephrine. ANG II or phenylephrine were infused over either
3 h or 3 days to conscious rats. NOS activity was examined by
measuring the rate of conversion of
L - 14 Carginine to
L - 14 Ccitrulline. Protein levels of
endothelial (e) and neuronal (n) NOS were determined by Western blot
analysis. Arterial pressure (AP) increased ( P < 0.05)
during acute and prolonged ANG II infusion. Ca 2+ -dependent
NOS activity values (pmol of
citrulline · min 1 · g wet
wt 1 ) for control rats were 21 ± 9 in mesenteric
arteries, 13 ± 7 in left ventricle, 14 ± 8 in renal cortex,
and 411 ± 70 in renal medulla. Acute ANG II infusion increased
( P < 0.05) Ca 2+ -dependent NOS activity in
renal cortex and renal medulla (81 ± 18 and 611 ± 48, respectively), but no differences were found in mesenteric arteries and
left ventricle with respect to control rats. In contrast to the renal
changes in NOS activity, acute ANG II infusion did not modify eNOS or
nNOS expression in any of the tissues examined. Prolonged ANG II
infusion increased ( P < 0.05)
Ca 2+ -dependent NOS activity in mesenteric arteries (70 ± 17), renal cortex (104 ± 31), and left ventricle (49 ± 8) and did not elicit changes in renal medulla. After a prolonged ANG
II infusion, eNOS and nNOS levels increased in all tissues examined
with the exception of eNOS in the mesenteric arteries and nNOS in the
left ventricle, which were not altered. Acute and prolonged
phenylephrine infusion elevated AP to a similar extent as ANG II but
only elicited significant increments of Ca 2+ -dependent NOS
activity in renal cortex. These data indicate that acute and prolonged
elevations in ANG II upregulate Ca 2+ -dependent NOS activity
and protein expression in different tissues related to the control of
blood pressure. However, these ANG II effects are heterogeneous with
respect to the tissue implicated, the time course of the stimulation,
and the NOS isoform involved. Phenylephrine only induces a significant
elevation of Ca 2+ -dependent NOS activity in renal cortex.
heart; mesenteric arteries; nitric oxide synthase; phenylephrine
renal cortex; renal medulla
The AS-48 bacteriocin is a potent antimicrobial polypeptide with enhanced stability due to its circular sequence of peptidic bonds. The mechanism of biological action is still not well understood in ...spite of both the elucidation of the molecular structure some years ago and several experiments performed that yielded valuable information about the AS-48 bacterial membrane poration activity. In this work, we present a computational study at an atomistic scale to analyze the membrane disruption mechanism. The process is based on the two-stage model: (1) peptide binding to the bilayer surface and (2) membrane poration due to the surface tension exerted by the peptide. Indeed, the induced membrane tension mechanism is able to explain stable formation of pores leading to membrane disruption. The atomistic detail obtained from the simulations allows one to envisage the contribution of the different amino acids during the poration process. Clustering of cationic residues and hydrophobic interactions between peptide and lipids seem to be essential ingredients in the process. GLU amino acids have shown to enhance the membrane disrupting ability of the bacteriocin. TRP24–TRP24 interactions make also an important contribution in the initial stages of the poration mechanism. The detailed atomistic information obtained from the simulations can serve to better understand bacteriocin structural characteristics to design more potent antimicrobial therapies.
PDF
