121 research outputs found
Hypotensive Effect Induced by Mandibular Extension in Aged, Hypertensive Humans and Rats
No full textObjectives: Previous research has shown that submaximal mouth opening by mandibular extension (ME) is followed by a prolonged reduction in blood pressure. This effect was observed in young and adult normotensive and hypertensive rats and in young normotensive human subjects.
Methods: We assessed the effects of a ME for 10 minutes obtained with a fixed mouth opener in both hypertensive adult humans (aged 55 years or older) and elderly (6-7 months) anaesthetized, hypertensive rats (SHR). Blood pressure and heart rate were measured every 10 minutes by non-invasive automatic recorders for 30 minutes before and 120 minutes after the procedure. Nine human hypertensive subjects (7 experimental and 2 controls) and seven spontaneously hypertensive rats (5 experimental and 2 controls) were tested.
Results: A statistically significant reduction in systolic blood pressure (SBP), mean arterial blood pressure (MABP) and heart rate (HR) was observed after ME in the seven hypertensive human subjects, in whom an average decrease of 15 mmHg for SBP, 10 mmHg for MABP and 7 bpm for HR, was observed. A similar hypotensive effect was recorded in spontaneously hypertensive rats that displayed a statistically significant decrease of SBP, DBP and MABP, amounting to about 40-50 mmHg.
Conclusion: This study provides the first evidence that ME has an important and prolonged hypotensive effect when applied to subjects with high blood pressure, making their arterial blood pressure decrease toward normal values for at least two hours
Repeated mandibular extension in rat: A procedure to modulate the cerebral arteriolar tone
No full textPrevious data have shown both in the rat and in the human that a single mandibular extension lasting 10 min induces a significant important and prolonged reduction in blood pressure and heart rate, affecting also rat pial microcirculation by the release of endothelial factors. In the present work, we assessed whether repeated mandibular extension could further prolong these effects. We performed two mandibular extensions, the second mandibular extension being applied 10 min after the first one. The second mandibular extension produced a reduction in blood pressure and heart rate for at least 240 min. As in the case of a single mandibular extension, pial arterioles dilated persisting up to 140 min after the second extension. Spectral analysis on 30 min recordings under baseline conditions and after repetitive mandibular extensions showed that the pial arterioles dilation was associated with rhythmic diameter changes sustained by an increase in the frequency components related to endothelial, neurogenic, and myogenic activity while a single mandibular extension caused, conversely, an increase only in the endothelial activity. In conclusion, repetitive mandibular extension prolonged the effects of a single mandibular extension on blood pressure, heart rate and vasodilation and induced a modulation of different frequency components responsible of the pial arteriolar tone, in particular increasing the endothelial activity
Evidence in the human of a hypotensive and a bradycardic effect after mouth opening maintained for 10 min
No full textPurpose: We have recently shown that in humans submaximal mouth opening associated with partial masticatory movements for 10 min is followed by a small but significant and prolonged reduction of blood pressure and heart rate. We here report the effects of a fixed mouth opener. Methods: In 22 seated normotensive volunteers the effect on blood pressure and heart rate was studied in randomized order after fixed mandibular extension and after a control procedure consisting in keeping a stick between the incisor teeth (both for 10 min). Automated recordings every 10 min were done for 40 min before and 120 min following the procedure. Results: Two-way ANOVA for repeated measures on absolute values (actual recordings) and on changes from baseline revealed that, compared to controls, systolic, diastolic and mean blood pressure and heart rate were significantly lower after mandibular extension. Compared to controls, mandibular extension induced an average blood pressure drop of 2.88 mmHg (systolic), 2.55 mmHg (diastolic) and 2.42 mmHg (mean) over the entire observation period. The average decline over the central part of the observation period (30th to 80th min) was, respectively, of 3.62, 3.70 and 3.61 mmHg. The decrements of heart rate were of 2.11 and 2.66 beats per min. All these differences were statistically significant. The hypotensive and bradycardic responses persisted for 70–120 min. Conclusions: This study shows that, in normotensives, a single fixed submaximal mouth opening for 10 min is followed by prolonged albeit small reductions of blood pressure and heart rate
Trigeminocardiac reflex by mandibular extension on rat pial microcirculation: Role of nitric oxide
No full textIn the present study we have extended our previous findings about the effects of 10 minutes of passive mandibular extension in anesthetized Wistar rats. By prolonging the observation time to 3 hours, we showed that 10 minutes mandibular extension caused a significant reduction of the mean arterial blood pressure and heart rate respect to baseline values, which persisted up to 160 minutes after mandibular extension. These effects were accompanied by a characteristic biphasic response of pial arterioles: during mandibular extension, pial arterioles constricted and after mandibular extension dilated for the whole observation period. Interestingly, the administration of the opioid receptor antagonist naloxone abolished the vasoconstriction observed during mandibular extension, while the administration of Nω-Nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, abolished the vasodilation observed after mandibular extension. Either drug did not affect the reduction of mean arterial blood pressure and heart rate induced by mandibular extension. By qRT-PCR, we also showed that neuronal nitric oxide synthase gene expression was significantly increased compared with baseline conditions during and after mandibular extension and endothelial nitric oxide synthase gene expression markedly increased at 2 hours after mandibular extension. Finally, western blotting detected a significant increase in neuronal and endothelial nitric oxide synthase protein expression. In conclusion mandibular extension caused complex effects on pial microcirculation involving opioid receptor activation and nitric oxide release by both neurons and endothelial vascular cells at different times
Evidence in hypertensive rats of hypotensive effect after mandibular extension
No full textPrevious studies in anesthetized normotensive rats demonstrated that a single mouth opening for 10 min obtained by an ad hoc dilator (mandibular extension [ME]) produced a blood pressure reduction by about 20 mmHg lasting for about 2 h and that once-repeated ME prolonged this effect. We here describe these effects in hypertensive rats. Mean (intra) arterial blood pressure (MABP) and heart rate (HR) was followed for up to a maximum of 470 min after single or repeated 10 min-lasting ME in two groups of anesthetized, male, 6-9 months old hypertensive rats. In one group, hypertension was induced by dexamethasone (20 μg/kg/day, subcutaneously for 7 days; Dex-HT); the other group was spontaneously hypertensive rats (SHR). Studies were done, in Dex-HT rats, after only surgical procedures (no ME, sham-operated rats), single ME, early repeated (after 10 min) ME (ER-ME) and late repeated (after 160 min) ME (LR-ME) and, in SHR, after only surgical procedures and ER-ME. One-way ANOVA for repeated measures revealed no significant effect on MABP and HR in sham-operated groups. In Dex-HT rats, single ME was followed by a significant MABP decline by 25 mmHg, lasting for 100 min; ER-ME and LR-ME were followed by an even greater significant MABP decline by 40 mmHg, which outlasted the experimental observation period. In SHR, ER-ME gave similar results as in Dex-HT rats. HR significantly declined in all, except sham-operated groups. In conclusions, ME is followed by a prolonged MABP decline also in hypertensive rats. This effect is even more pronounced, in length and magnitude, after repeated ME
Survival kinase-dependent pathways contribute to gender difference in the response to myocardial ischemia–reperfusion and ischemic post-conditioning
No full textThe response to ischemia/reperfusion and the effects of ischemic post-conditioning (IPC) are sex-dependent, but the mechanisms have not been clarified. Male (M) and female (F) rat hearts isolated and perfused using the Langendorff technique were subject to 30 min of global ischemia (GI) and 60 min reperfusion (R). In IPC hearts, three cycles of 30-sec GI/30-sec R were applied at the beginning of R. Infarct size and myocardial function were assessed. Superoxide production, antioxidant systems, and expressions of phosphorylated forms of serine/threonine kinase (Akt), glycogen synthase kinase 3β (GSK-3β), protein kinase C ε (PKCε), endothelial nitric oxide synthase (eNOS), and apoptosis were measured. In the basal state, superoxide production and apoptosis were lower, and antioxidant systems and phospho-kinase expressions were higher in F rather than in M hearts. After ischemia–reperfusion, infarct size was less in F hearts, and post-ischemic recovery of myocardial function was higher in F rather than in M hearts. Superoxide production, phospho-kinase activity, phospho-eNOS, and apoptosis increased in both sexes while antioxidants decreased in both sexes. After IPC, infarct size, superoxide production, and apoptosis decreased and phospho-eNOS increased in F and M hearts but phospho-kinase expressions and post-ischemic recovery of myocardial function improved only in M hearts. These results show that Akt/GSK-3β/PKCε/eNOS-dependent pathways-mediated superoxide production and apoptosis appear as important factors involved in the observed gender differences.Fil: Ciocci Pardo, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Scuriatti, Luis Emiliano. Universidad Nacional de La Plata. Facultad de Ciencias Médicas; ArgentinaFil: González Arbeláez LF. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Caldiz, CI. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Fantinelli JC. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; ArgentinaFil: Mosca SM. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; Argentin
Translating Place Identity into Transmedia Communication Systems: Communication Design Process and Methods
No full textThe paper discusses the role of Communication Design in promoting cultural heritage and enhancing local identity. It deals with the need of designing communication systems able to increase people's understanding and engagement with a given place.
We argue that a communication strategy able to leverage on both tangible and intangible aspects of place identity leads to a more mindful tourism consumption, and it is a means to strengthen citizens' sense of belonging as well. To this aim, we highlight the importance of blending cultural information with technologies and languages to make the exploration of a place more accessible and meaningful. Specifically, our research focuses on the contribution given by “immersive languages” to strengthen the relation between human and environment.
Here, great emphasis is put on the transformative function of design that lies in the ability of translating and transferring intangible elements into digital products and communication systems. As an example of this translating process, the paper present a didactic experience with a class of MSc students in Communication Design. They were asked to design transmedia communication systems for exploring the city of Milan through literary paths. Every transmedia system aims to represent the specific point of view of an author and the context in which he lived and worked. The main project goal was to create a complex mixing of media, languages and medium, in order to engage users on different channels, foster the exploration of the city and support the development of new knowledge about its identity.
The paper will describe each step of the design process focusing on approach and methods adopted to foster and nurture the projects development
LASP1 directly interacts with vimentin and its expression stratifies patients affected by human hepatocellular carcinoma
No full textLASP1 directly interacts with vimentin and its expression stratifies patients affected by human hepatocellular carcinom
Effects of ischemic postconditioning on isolated hearts of males and females
No full textNuestro objetivo fue determinar los efectos del post-acondicionamiento isquémico (PCI) sobre las alteraciones miocárdicas producidas por la isquemia-reperfusión en ratas Wistar machos (M) y hembras (H) adultas jóvenes (4-5 meses de edad). Los corazones aislados y perfundidos por el sistema de Langendorff, después de un período de estabilización de 20 min fueron asignados a los siguientes grupos experimentales: 1) Control no isquémico (C): perfusión durante 90 min; 2) Control isquémico (CI): 30 min de isquemia global (IG) y 60 min de reperfusión (R); 3) PCI: 30 min de IG y luego se aplicaron, al inicio de la R, 3 ciclos de 30 seg de IG y 30 seg de R. Al final de R se determinó el tamaño del infarto (TI) mediante la tinción con sales de trifeniltetrazolio. La función sistólica fue determinada a través de la presión desarrollada del ventrículo izquierdo (PDVI) y la velocidad máxima de ascenso de la presión (+dP/dtmax). La función diastólica se evaluó a través de la velocidad máxima de descenso de la presión (-dP/dtmax), del tiempo hasta la mitad de la relajación (t50), de la constante de tiempo de relajación () y de la presión diastólica final del ventrículo izquierdo (PDFVI) como índice de rigidez diastólica. En el grupo CI el TI fue significativamente mayor en M que en H (40 ± 2 % vs. 29 ± 4 %, respectivamente, p < 0.05). La PDVI y la +dP/dtmax al final de los 60 min de R fue de 19 ± 4 % y 23 ± 5 % en M y de 55 ± 3 % y 59 ± 7 % en H (p < 0.05). La ?dP/dtmax fue 21 ± 4 % para M y 54 ± 7 % para H (p < 0.05). La PDFVI fue de 50 ± 4 mmHg para M y de 26 ± 8 mmHg para H (p < 0.05). t50 no mostró cambios. aumentó a los 5 y 10 min de R y se normalizó al final de R sólo en M. El PCI disminuyó significativamente el TI en M y H (16 ± 1 % y 15 ± 1 %, respectivamente, p < 0.05) pero aumentó la recuperación post-isquémica de la función sistólica y diastólica sólo en M. Estos resultados muestran que en ratas Wistar adultas jóvenes: 1) el TI y la función miocárdica post-isquémica fue significativamente mayor en H que en M; 2) el PCI disminuyó el TI en corazones de ambos sexos, y 3) el PCI mejoró la recuperación post-isquémica de la función cardíaca en M y no la modificó en H. Estos datos sugieren que el PCI es una herramienta cardioprotectora más efectiva en M que en H.Our objective was to determine the effects of ischemic postconditioning (IPC) on myocardial alterations caused by ischemia-reperfusion in male (M) and female (F) young adult (4-5 months old) Wistar rats. After a 20-min stabilization period, isolated hearts perfused by the Langendorff system were assigned to the following experimental groups: 1) Non-ischemic control (NIC): perfusion for 90 min; 2) Ischemic control (IC): 30-min global ischemia (GI) and 60-min reperfusion (R); 3) IPC: 3 cycles of 30 sec of GI and 30 sec of R at the beginning of R. Infarction size (IS) was determined by TTC staining technique. Systolic function was assessed by the developed pressure of left ventricle (LVDP) and the maximum rate of rise of left ventricular pressure (+dP/dtmax). Diastolic function was measured using the maximum rate of decrease of left ventricular pressure (–dP/dtmax), half-relaxation time (t50), time constant of relaxation (τ) and left ventricular end diastolic pressure (LVEDP) as an index of diastolic stiffness. In the IC group the IS was significantly higher in M than F (40 ± 2% vs. 29 ± 4%, respectively; p<0.05). At the end of R, LVDP and +dP/dtmax were higher in F compared to M. The values were 19 ± 4% and 23 ± 5% for M and 55 ± 3% and 59 ± 7% for F (p<0.05). Similarly the –dP/dtmax was higher in F than M (54 ± 7% and 21 ± 4%, respectively; p<0.05). LVEDP was 50 ± 4 mmHg for M and 26 ± 8 mmHg for F (p<0.05). t50 did not change in M and F, increased at 5 and 10 min of R and normalized at the end of R only in M. IPC significantly decreased IS in hearts from both sexes (16 ± 1% and 15 ± 1% for M and F, respectively) but increased the post-ischemic recovery of systolic and diastolic myocardial function only in M. These results show that in Wistar rats young adults: 1) IS and post-ischemic myocardial function was significantly higher in M than F; 2) IPC decreased IS in hearts from both sexes; 3) IPC improved post-ischemic recovery of myocardial function in M but did not modify it in F. These data suggest that IPC is a more effective cardioprotective tool in M than in F.Fil: Scur, Sergio. Hospital Italiano de La Plata; ArgentinaFil: Ciocci Pardo, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares ; ArgentinaFil: Mosca, Susana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares ; Argentin
Estudio observacional del estado auditivo de adolescentes y jóvenes aspirantes a una institución pública
No full textMillones de personas en el mundo experimentan pérdida de la audición inducida por el ruido, consecuencia de la excesiva exposición a sonidos tanto en el ámbito ocupacional como recreacional, siendo ejemplo el uso de reproductores portátil de música (RPM). Actualmente los problemas de audición afectan a personas cada vez más jóvenes, producto de la modernidad, por lo que aumentó la población expuesta a sufrir síntomas auditivos. El trauma acústico agudo (TAA) es la exposición coclear a un ruido muy intenso y el trauma acústico crónico (TAC) la exposición mantenida a intensidades superiores a 90 dB. La audiometría valora la pérdida auditiva. El TAA y TAC muestran perfiles audiométricos característicos. La pérdida de la audición suele ser minimizada o ignorada, constituyéndose en un verdadero problema para la salud pública.Facultad de Ciencias Médica
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