973 resultados para (Drop-) stones


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Acid-sensing ion channels (ASICs) are neuronal Na(+) channels that belong to the epithelial Na(+) channel/degenerin family. ASICs are transiently activated by a rapid drop in extracellular pH. Conditions of low extracellular pH, such as ischemia and inflammation in which ASICs are thought to be active, are accompanied by increased protease activity. We show here that serine proteases modulate the function of ASIC1a and ASIC1b but not of ASIC2a and ASIC3. We show that protease exposure shifts the pH dependence of ASIC1a activation and steady-state inactivation to more acidic pH. As a consequence, protease exposure leads to a decrease in current response if ASIC1a is activated by a pH drop from pH 7.4. If, however, acidification occurs from a basal pH of approximately 7, protease-exposed ASIC1a shows higher activity than untreated ASIC1a. We provide evidence that this bi-directional regulation of ASIC1a function also occurs in neurons. Thus, we have identified a mechanism that modulates ASIC function and may allow ASIC1a to adapt its gating to situations of persistent extracellular acidification.

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OBJECTIVE: Transthoracic echocardiography (TTE) has been used clinically to disobstruct venous drainage cannula and to optimise placement of venous cannulae in the vena cava but it has never been used to evaluate performance capabilities. Also, little progress has been made in venous cannula design in order to optimise venous return to the heart lung machine. We designed a self-expandable Smartcanula (SC) and analysed its performance capability using echocardiography. METHODS: An epicardial echocardiography probe was placed over the SC or control cannula (CTRL) and a Doppler image was obtained. Mean (V(m)) and maximum (V(max)) velocities, flow and diameter were obtained. Also, pressure drop (DeltaP(CPB)) was obtained between the central venous pressure and inlet to venous reservoir. LDH and Free Hb were also compared in 30 patients. Comparison was made between the two groups using the student's t-test with statistical significance established when p<0.05. RESULTS: Age for the SC and CC groups were 61.6+/-17.6 years and 64.6+/-13.1 years, respectively. Weight was 70.3+/-11.6 kg and 72.8+/-14.4 kg, respectively. BSA was 1.80+/-0.2 m(2) and 1.82+/-0.2 m(2), respectively. CPB times were 114+/-53 min and 108+/-44 min, respectively. Cross-clamp time was 59+/-15 min and 76+/-29 min, respectively (p=NS). Free-Hb was 568+/-142 U/l versus 549+/-271 U/l post-CPB for the SC and CC, respectively (p=NS). LDH was 335+/-73 mg/l versus 354+/-116 mg/l for the SC and CC, respectively (p=NS). V(m) was 89+/-10 cm/s (SC) versus 63+/-3 cm/s (CC), V(max) was 139+/-23 cm/s (SC) versus 93+/-11 cm/s (CC) (both p<0.01). DeltaP(CPB) was 30+/-10 mmHg (SC) versus 43+/-13 mmHg (CC) (p<0.05). A Bland-Altman test showed good agreement between the two devices used concerning flow rate calculations between CPB and TTE (bias 300 ml+/-700 ml standard deviation). CONCLUSIONS: This novel Smartcanula design, due to its self-expanding principle, provides superior flow characteristics compared to classic two stage venous cannula used for adult CPB surgery. No detrimental effects were observed concerning blood damage. Echocardiography was effective in analysing venous cannula performance and velocity patterns.

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Critics of the U.S. proposal to the World Trade Organization (WTO) made in October 2005 are correct when they argue that adoption of the proposal would significantly reduce available support under the current farm program structure. Using historical prices and yields from 1980 to 2004, we estimate that loan rates would have to drop by 9 percent and target prices would have to drop by 10 percent in order to meet the proposed aggregate Amber Box and Blue Box limits. While this finding should cheer those who think that reform of U.S. farm programs is long overdue, it alarms those who want to maintain a strong safety net for U.S. agriculture. The dilemma of needing to reform farm programs while maintaining a strong safety net could be resolved by redesigning programs so that they target revenue rather than price. Building on a base of 70 percent Green Box income insurance, a program that provides a crop-specific revenue guarantee equal to 98 percent of the product of the current effective target price and expected county yield would fit into the proposed aggregate Amber and Blue Box limits. Payments would be triggered whenever the product of the season-average price and county average yield fell below this 98 percent revenue guarantee. Adding the proposed crop-specific constraints lowers the coverage level to 95 percent. Moving from programs that target price to ones that target revenue would eliminate the rationale for ad hoc disaster payments. Program payments would automatically arrive whenever significant crop losses or economic losses caused by low prices occurred. Also, much of the need for the complicated mechanism (the Standard Reinsurance Agreement) that transfers most risk of the U.S. crop insurance to the federal government would be eliminated because the federal government would directly assume the risk through farm programs. Changing the focus of federal farm programs from price targeting to revenue targeting would not be easy. Farmers have long relied on price supports and the knowledge that crop losses are often adequately covered by heavily subsidized crop insurance or by ad hoc disaster payments. Farmers and their leaders would only be willing to support a change to revenue targeting if they see that the current system is untenable in an era of tight federal budgets and WTO limits.

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PURPOSE: To evaluate subconjunctival mitomycin C (MMC) injection efficacy and safety in patients with failing glaucoma non-penetrating filtering blebs. METHODS: Twenty-eight eyes were consecutively recruited for this study. Only one eye for each patient was randomly selected. All the recruited patients had glaucoma and uncontrolled intraocular pressure after a non-penetrating filtering glaucoma surgery and/or a pathological aspect of the filtering bleb (i.e., vascularized and/or encysted). One or more MMC injections were performed under the conjunctiva closed to the bleb to improve filtration. Local effects and complications of subconjunctival MMC injections were analyzed. RESULTS: Out of the 28 patients, 21 (75%) had MMC also applied intraoperatively. The mean postoperative IOP before MMC injections was 17 +/- 6.6 mmHg. The final IOP after MMC injections was 13.9 +/- 2.9 mmHg after a mean follow-up of 6 months. A total of 67 subconjunctival MMC injections were performed with a mean of 2.9 (ranging from 1 to 5) injections per patient. The only complication found to be possibly related to MMC injections was two cases of corneal Dellen. CONCLUSION: From these preliminary results, subconjunctival MMC injections in selected cases appear to be not only safe but also effective in promoting further the postoperative IOP drop.

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The key role of intrarenal adenosine in mediating the hypoxemic acute renal insufficiency in newborn rabbits has been well demonstrated using the nonspecific adenosine antagonist theophylline. The present study was designed to define the role of adenosine A1 receptors during systemic hypoxemia by using the specific A1-receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX). Renal function parameters were assessed in 31 anesthetized and mechanically ventilated newborn rabbits. In normoxia, DPCPX infusion induced a significant increase in diuresis (+44%) and GFR (+19%), despite a significant decrease in renal blood flow (RBF) (-22%) and an increase in renal vascular resistance (RVR) (+37%). In hypoxemic conditions, diuresis (-19%), GFR (-26%), and RBF (-35%) were decreased, whereas RVR increased (+33%). DPCPX administration hindered the hypoxemia-induced decrease in GFR and diuresis. However, RBF was still significantly decreased (-27%), whereas RVR increased (+22%). In all groups, the filtration fraction increased significantly. The overall results support the hypothesis that, in physiologic conditions, intrarenal adenosine plays a key role in regulating glomerular filtration in the neonatal period through preferential A1-mediated afferent vasoconstriction. During a hypoxemic stress, the A1-specific antagonist DPCPX only partially prevented the hypoxemia-induced changes, as illustrated by the elevated RVR and drop in RBF. These findings imply that the contribution of intrarenal adenosine to the acute adverse effects of hypoxemia might not be solely mediated via the A1 receptor.

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STATEMENT OF PROBLEM: Wear of methacrylate artificial teeth resulting in vertical loss is a problem for both dentists and patients. PURPOSE: The purpose of this study was to quantify wear of artificial teeth in vivo and to relate it to subject and tooth variables. MATERIAL AND METHODS: Twenty-eight subjects treated with complete dentures received 2 artificial tooth materials (polymethyl methacrylate (PMMA)/double-cross linked PMMA fillers; 35%/59% (SR Antaris DCL, SR Postaris DCL); experimental 48%/46%). At baseline and after 12 months, impressions of the dentures were poured with improved stone. After laser scanning, the casts were superimposed and matched. Maximal vertical loss (mm) and volumetric loss (mm(3)) were calculated for each tooth and log-transformed to reduce variability. Volumetric loss was related to the occlusally active surface area. Linear mixed models were used to study the influence of the factors jaw, tooth, and material on adjusted (residual) wear values (alpha=.05). RESULTS: Due to drop outs (n=5) and unmatchable casts (n=3), 69% of all teeth were analyzed. Volumetric loss had a strong linear relationship to surface area (P<.001); this was less pronounced for vertical loss (P=.004). The factor showing the highest influence was the subject. Wear was tooth dependent (increasing from incisors to molars). However, these differences diminished once the wear rates were adjusted for occlusal area, and only a few remained significant (anterior versus posterior maxillary teeth). Another influencing factor was the age of the subject. CONCLUSIONS: Clinical wear of artificial teeth is higher than previously measured or expected. The presented method of analyzing wear of artificial teeth using a laser-scanning device seemed suitable.

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The deep drop of the fertility rate in Italy to among the lowest in the world challenges contemporary theories of childbearing and family building. Among high-income countries, Italy was presumed to have characteristics of family values and female labor force participation that would favor higher fertility than its European neighbors to the north. We test competing economic and cultural explanations, drawing on new nationally representative, longitudinal data to examine first union, first birth, and second birth. Our event history analysis finds some support for economic determinants of family formation and fertility, but the clear importance of regional differences and of secularization suggests that such an explanation is at best incomplete and that cultural and ideational factors must be considered.

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AIM: To prospectively study the intraocular pressure (IOP) lowering effect and safety of the new method of very deep sclerectomy with collagen implant (VDSCI) compared with standard deep sclerectomy with collagen implant (DSCI). METHODS: The trial involved 50 eyes of 48 patients with medically uncontrolled primary and secondary open-angle glaucoma, randomized to undergo either VDSCI procedure (25 eyes) or DSCI procedure (25 eyes). Follow-up examinations were performed before surgery and after surgery at day 1, at week 1, at months 1, 2, 3, 6, 9, 12, 18, and 24 months. Ultrasound biomicroscopy was performed at 3 and 12 months. RESULTS: Mean follow-up period was 18.6+/-5.9 (VDSCI) and 18.9+/-3.6 (DSCI) months (P=NS). Mean preoperative IOP was 22.4+/-7.4 mm Hg for VDSCI and 20.4+/-4.4 mm Hg for DSCI eyes (P=NS). Mean postoperative IOP was 3.9+/-2.3 (VDSCI) and 6.3+/-4.3 (DSCI) (P<0.05) at day 1, and 12.2+/-3.9 (VDSCI) and 13.3+/-3.4 (DSCI) (P=NS) at month 24. At the last visit, the complete success rate (defined as an IOP of < or =18 mm Hg and a percentage drop of at least 20%, achieved without medication) was 57% in VDSCI and 62% in DSCI eyes (P=NS) ultrasound biomicroscopy at 12 months showed a mean volume of the subconjunctival filtering bleb of 3.9+/-4.2 mm3 (VDSCI) and 6.8+/-7.5 mm3 (DSCI) (P=0.426) and 5.2+/-3.6 mm3 (VDSCI) and 5.4+/-2.9 mm3 (DSCI) (P=0.902) for the intrascleral space. CONCLUSIONS: Very deep sclerectomy seems to provide stable and good control of IOP at 2 years of follow-up with few postoperative complications similar to standard deep sclerectomy with the collagen implant.

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Atherosclerotic renal artery disease represents a cause of which little is known but not a cause to be neglected for hypertension and renal insufficiency. Even though its occurrence remains badly defined, atherosclerotic renal artery disease is constantly on the rise due to the aging population, the never prevailing hypertension and diabetes mellitus. This review aims to give a clinical profile of patients presenting with atherosclerotic renal artery disease and to discuss, in the light of study results, which diagnostic evaluation should be used considering the sequence and the benefit and risk of each in order to initiate a personalized treatment. Patients affected by atherosclerotic renal artery disease are likely to have more complications and more extensive target-organ damage than patients without renal artery stenosis. The evolution of the atherosclerotic renal artery disease is in general slow and progressive. Nevertheless, certain clinical cases manifest themselves with the onset of acute renal failure bought upon by the administration of blockers of the rennin-angiotensin-aldosterone system, or by some other causes responsible for a sudden drop in renal plasma flow (e.g., thrombosis of the renal artery). The relationship between atherosclerotic renal artery disease and atherosclerosis is complex, and mediators implicated in the pathophysiology of renovascular disease may also contribute to the progression of cardiovascular damage. An early assumption of the atherosclerotic renal artery stenosis is warranted to determine the adapted treatment (i.e., medical treatment, revascularisation...) just as the assumption and the correction of the more general cardiovascular risk factors.

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We analyzed prenatal care (PN) provided at a unit of the Family Health Strategy Service in São Paulo, according to the indicators of the Program for the Humanization of Prenatal and Birth (PHPB). We compared adequacy of PN in terms of sociodemographic variables, procedures, examinations and maternal and perinatal outcomes. Cross-sectional study with data from records of 308 pregnant women enrolled in 2011. We observed early initiation of PN (82.1%), conducting of a minimum of six consultations (84.1%), puerperal consultation (89.0%); to the extent that there is a sum of the actions, there is a significant drop in the proportion of adequacy. Prenatal care was adequate for 67.9%, with a significant difference between adequacy groups in relation to gestational age and birth weight. Prenatal care deficiencies exist, especially in regards to registration of procedures, exams and immunization. The difference between adequacy groups with respect to perinatal outcomes reinforces the importance of prenatal care that adheres to the parameters of the PHPB.


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Objective To verify the effect of bathing on the body temperature of preterm infants (PTI). Method Systematic review conducted in the following bibliographic electronic sources: Biblioteca Virtual em Saúde/Lilacs (BVS), Cumulated Index of Nursing and Allied Health Literature (CINAHL), Cochrane Library, Google Scholar, PubMed, SCOPUS and Web of Science, using a combination of search terms, keywords and free terms. The review question was adjusted to the PICO acronym (Patient/population, Intervention, Control/comparative intervention, Outcome). The selected publications were evaluated according to levels of evidence and grades of recommendation for efficacy/effectiveness studies, as established by the Joanna Briggs Institute. Results Eight hundred and twenty four (824) publications were identified and four studies met the inclusion criteria, of which three analyzed the effect of sponge baths and the effect of immersion baths. Conclusion Sponge baths showed a statistically significant drop in body temperature, while in immersion baths the body temperature remained stable, although they studied late preterm infants.

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A continental subduction-related and multistage exhumation process for the Tso Morari ultra-high pressure nappe is proposed. The model is constrained by published thermo-barometry and age data, combined with new geological and tectonic maps. Additionally, observations on the structural and metamorphic evolution of the Tso Morari area and the North Himalayan nappes are presented. The northern margin of the Indian continental crust was subducted to a depth of >90 km below Asia after continental collision some 55 Ma ago. The underthrusting was accompanied by the detachment and accretion of Late Proterozoic to Early Eocene sediments, creating the North Himalayan accretionary wedge, in front of the active Asian margin and the 103-50 Ma Ladakh arc batholith. The basic dikes in the Ordovician Tso Morari granite were transformed to eclogites with crystallization of coesite, some 53 Ma ago at a depth of >90 kin (>27 kbar) and temperatures of 500 to 600 degrees C. The detachment and extrusion of the low density Tso Morari nappe, composed of 70% of the Tso Morari granite and 30% of graywackes with some eclogitic dikes, occurred by ductile pure and simple shear deformation. It was pushed by buoyancy forces and by squeezing between the underthrusted Indian lithosphere and the Asian mantle wedge. The extruding Tso Morari nappe reached a depth of 35 km at the base of the North Himalayan accretionary wedge some 48 Ma ago. There the whole nappe stack recrystallized under amphibolite facies conditions of a Barrovian regional metamorphism with a metamorphic field gradient of 20 degrees C/km. An intense schistosity with a W-E oriented stretching lineation L, and top-to-the E shear criteria and crystallization of oriented sillimanite needles after kyanite, testify to the Tso Morari nappe extrusion and pressure drop. The whole nappe stack, comprising from the base to top the Tso Morari, Tetraogal, Karzok and Mata-Nyimaling-Tsarap nappes, was overprinted by new schistosities with a first N-directed and a second NE-directed stretching lineation L-2 and L-3 reaching the base of the North Himalayan accretionary wedge. They are characterized by top-to-the S and SW shear criteria. This structural overprint was related to an early N- and a younger NE-directed underthrusting of the Indian plate below Asia that was accompanied by anticlockwise rotation of India. The warping of the Tso Morari dome started already some 48 Ma ago with the formation of an extruding nappe at depth. The Tso Morari dome reached a depth of 15 km about 40 Ma ago in the eastern Kiagar La region and 30 Ma ago in the western Nuruchan region. The extrusion rate was of about 3 cm/yr between 53 and 48 Ma, followed by an uplift rate of 1.2 mm/yr between 48 and 30 Ma and of only 0.5 mm/yr after 30 Ma. Geomorphology observations show that the Tso Morari dome is still affected by faults, open regional dome, and basin and pull-apart structures, in a zone of active dextral transpression parallel to the Indus Suture zone.

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PURPOSE: To investigate the effect of intraocular straylight (IOS) induced by white opacity filters (WOF) on threshold measurements for stimuli employed in three perimeters: standard automated perimetry (SAP), pulsar perimetry (PP) and the Moorfields motion displacement test (MDT).¦METHODS: Four healthy young (24-28 years old) observers were tested six times with each perimeter, each time with one of five different WOFs and once without, inducing various levels of IOS (from 10% to 200%). An increase in IOS was measured with a straylight meter. The change in sensitivity from baseline was normalized, allowing comparison of standardized (z) scores (change divided by the SD of normative values) for each instrument.¦RESULTS: SAP and PP thresholds were significantly affected (P < 0.001) by moderate to large increases in IOS (50%-200%). The drop in motion displacement (MD) from baseline with WOF 5, was approximately 5 dB, in both SAP and PP which represents a clinically significant loss; in contrast the change in MD with MDT was on average 1 minute of arc, which is not likely to indicate a clinically significant loss.¦CONCLUSIONS: The Moorfields MDT is more robust to the effects of additional straylight in comparison with SAP or PP.

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We present a comparative analysis of satellite derived climatologies in the Cape Verde region (CV). In order to establish chlorophyll a variability, in relation to other oceanographic phenomena, a set of, relatively long (from five to eight years), time series of chlorophyll a, sea surface temperature, wind and geostrophic currents, were ensembled for the Eastern Central Atlantic (ECA). We studied seasonal and inter-annual variability of phytoplankton concentration, in relation to the rest of the variables, with a special focus in CV. We compared the situation within the archipelago with those of the surrounding marine environments, such as the North West African Upwelling (NWAU), North Atlantic Subtropical Gyre (NASTG), North Equatorial Counter Current (NECC) and Guinea Dome (GD). At the seasonal scale, CV region behaves partly as the surrounding areas, nevertheless, some autochthonous features were also found. The maximum peak of the pigment having a positive correlation with temperature is found at the end of the year for all the points in the archipelago; a less remarkable rise with negative correlation is also detected in February for points CV2 and CV4. This is behavior that none of the surrounding environments have shown. This enrichment was found to be preceded by a drastic drop in wind intensity (SW Monsoon) during summer months. The inter-annual analysis shows a tendency for decreasing of the chlorophyll a concentration.

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We present a comparative analysis of satellite derived climatologies in the Cape Verde region (CV). In order to establish chlorophyll a variability, in relation to other oceanographic phenomena, a set of, relatively long (from five to eight years), time series of chlorophyll a, sea surface temperature, wind and geostrophic currents, were ensembled for the Eastern Central Atlantic (ECA). We studied seasonal and inter-annual variability of phytoplankton concentration, in relation to the rest of the variables, with a special focus in CV. We compared the situation within the archipelago with those of the surrounding marine environments, such as the North West African Upwelling (NWAU), North Atlantic Subtropical Gyre (NASTG), North Equatorial Counter Current (NECC) and Guinea Dome (GD). At the seasonal scale, CV region behaves partly as the surrounding areas, nevertheless, some autochthonous features were also found. The maximum peak of the pigment having a positive correlation with temperature is found at the end of the year for all the points in the archipelago; a less remarkable rise with negative correlation is also detected in February for points CV2 and CV4. This is behavior that none of the surrounding environments have shown. This enrichment was found to be preceded by a drastic drop in wind intensity (SW Monsoon) during summer months. The inter-annual analysis shows a tendency for decreasing of the chlorophyll a concentration.