25 research outputs found
Approximate Analytical Model for the Squeeze-Film Lubrication of the Human Ankle Joint with Synovial Fluid Filtrated by Articular Cartilage
The aim of this article is to propose an analytical approximate squeeze-film lubrication model of the human ankle joint for a quick assessment of the synovial pressure field and the load carrying due to the squeeze motion. The model starts from the theory of boosted lubrication for the human articular joints lubrication (Walker et al., Rheum Dis 27:512â520, 1968; Maroudas, Lubrication and wear in joints. Sector, London, 1969) and takes into account the fluid transport across the articular cartilage using Darcyâs equation to depict the synovial fluid motion through a porous cartilage matrix. The human ankle joint is assumed to be cylindrical enabling motion in the sagittal plane only. The proposed model is based on a modified Reynolds equation; its integration allows to obtain a quick assessment on the synovial pressure field showing a good agreement with those obtained numerically (Hlavacek, J Biomech 33:1415â1422, 2000). The analytical integration allows the closed form description of the synovial fluid film force and the calculation of the unsteady gap thickness
Anterior fundoplication at the time of congenital diaphragmatic hernia repair
The loss of normal anatomic barriers in neonates with congenital diaphragmatic hernia (CDH) can predispose children to gastroesophageal reflux (GER). In an attempt to improve post-operative feeding, we have added a modified anterior fundoplication to restore natural gastric and esophageal positioning.
The institutional review board of both participating centers approved this study. Between 1997 and 2008, 13 neonates with high-risk anatomy underwent repair of CDH combined with an anterior fundoplication (Boix-Ochoa). The anatomic indications for concomitant fundoplication were absence of an intra-abdominal esophagus, an obtuse angle of His, and a small, vertically oriented stomach.
Ten patients survived to discharge and eight were on full oral nourishment. One required partial gastrostomy feedings for an improving oral aversion and quickly progressed to full oral feedings. One patient with chromosomal anomalies and swallowing dysfunction remained on long-term bolus gastrostomy feedings. Two with progressive symptoms of GER and failure to thrive required conversion to a 360° wrap after 18 months of medical management. This was performed in conjunction with a planned, staged muscle flap reconstruction in one patient. There were no complications related to the fundoplication.
Anatomic predictors of severe GER can be efficiently countered at the time of CDH repair. A modified fundoplication should be considered in the operative management of high-risk infants
Harmful marine microalgae in coastal waters of Chubut (Patagonia, Argentina)
A Harmful Algal Blooms Regional Monitoring Program has been carried out in Chubut coastal waters (Patagonia, Argentina) since the year 2000. This program surveys an extended shoreline, with bays and gulfs with shellfish natural banks and farms. Paralytic shellfish poison (PSP)-toxin-producing species, A. tamarense, have been observed during the study period; in addition, species producing diarrheic shellfish poison (DSP)-toxins, such as Dinophysis acuminata and D. tripos and Prorocentrum lima, and amnesic shellfish poison (ASP)-toxins, as several species of genus Pseudo-nitzschia, have been identified. Moreover, the production of the three types of toxins has been proven. Other harmful but nontoxic species have been registered in the area. The aim of this review is to show the temporal and spatial distribution of harmful microalgae species, the environmental factors associated with their occurrence, and their relation to toxic outbreaks during more than 15 years of observations, with special attention focused on the episodes of human intoxications. In addition, we discussed the accumulation and transfer of some phycotoxins through pelagic food webs, from the first trophic levels to large marine mammals, such as whales.Fil: Sastre, Alicia Viviana. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew. Departamento de BiologĂa. Laboratorio de HidrobiologĂa; ArgentinaFil: Santinelli, Norma Herminia. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew. Departamento de BiologĂa. Laboratorio de HidrobiologĂa; ArgentinaFil: Solis, Miriam Edith. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Centro Nacional PatagĂłnico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Perez, Laura Beatriz. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: DĂaz Ovejero, Soledad. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Gracia Villalobos, Leilen Luciana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Centro Nacional PatagĂłnico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: CadaillĂłn, Andreana Mackenna. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: D'agostino, Valeria Carina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Centro Nacional PatagĂłnico. Centro para el Estudio de Sistemas Marinos; Argentin
Association of Pre-Operative Albuminuria with Post-Operative Outcomes after Coronary Artery Bypass Grafting
The effect on post-operative outcomes after coronary artery bypass graft(CABG) surgery is not clear. Among 17,812 patients who underwent CABG during October 1,2006-September 28,2012 in any Department of US Veterans Affairs(VA) hospital, we identified 5,968 with available preoperative urine albumin-creatinine ratio(UACR) measurements. We examined the association of UACR<30, 30â299 and >=300âmg/g with 30/90/180/365-day and overall all-cause mortality, and hospitalization length >10 days, and with acute kidney injury(AKI). Meanâ±âSD baseline age and eGFR were 66â±â8 years and 77â±â19âml/min/1.73âm(2), respectively. 788 patients(13.2%) died during a median follow-up of 3.2 years, and 26.8% patients developed AKI(23.1%-Stage 1; 2.9%-Stage 2; 0.8%-Stage 3) within 30 days of CABG. The median lengths of stay were 8 days(IQR: 6â13 days), 10 days(IQR: 7â14 days) and 12 days(IQR: 8â19 days) for groups with UACR < 30âmg/g, 30â299âmg/g and â„300âmg/g, respectively. Higher UACR conferred 72 to 85% higher 90-, 180-, and 365-day mortality compared to UACR<30âmg/g (odds ratio and 95% confidence interval for UACRâ„300 vs. <30âmg/g: 1.72(1.01â2.95); 1.85(1.14â3.01); 1.74(1.15â2.61), respectively). Higher UACR was also associated with significantly longer hospitalizations and higher incidence of all stages of AKI. Higher UACR is associated with significantly higher odds of mortality, longer post-CABG hospitalization, and higher AKI incidence
Left Ventricular Diastolic Dysfunction in a Rat Model of Diabetic Cardiomyopathy using ECG-gated 18F-FDG PET
Underlying the Relationship Between Governance and Economic Growth in Developed Countries
Mesozooplankton structure and seasonal dynamics in three coastal systems of Argentina: BahĂa Blanca Estuary, Nuevo Gulf and Ushuaia Bay
Mesozooplankton communities in coastal ecosystems have successfully adapted to a wide range of environments. However, the current rate of coastal modification is challenging the survival of resident species. In this chapter, we describe the structure and annual dynamics of the mesozooplankton community in recent years for three coastal systems in Argentina that are subject to human disturbance: (1) BahĂa Blanca Estuary, (2) PirĂĄmide Bay in Nuevo Gulf and (3) Ushuaia Bay in the Beagle Channel. The seasonal dynamics of mesozooplankton abundance in BahĂa Blanca Estuary during 2009-2010 exhibited a unimodal pattern with an increase during the warm seasons, while organism abundance increased linearly with both salinity and turbidity. In Nuevo Gulf, research on the seasonal dynamics of mesozooplankton conducted during 2014-2015 exhibited a bimodal abundance pattern with peaks in late summer and spring. No significant relationships between mesozooplankton and the environmental variables included in Nuevo Gulf were found. The seasonal dynamics of mesozooplankton in Ushuaia Bay in the years 2006-2008 exhibited a bimodal abundance pattern with peaks in summer and early autumn; this pattern was mainly driven by the concentration of chlorophyll a. In BahĂa Blanca Estuary, a gradual decrease in species richness was observed throughout the last four decades, while changes in species composition were also observed, suggesting that some species have the ability to acclimate to higher salinity and turbidity as well as to pollution. In Nuevo Gulf, the mesozooplankton community showed no significant modifications over time, which may be related to the low anthropogenic pressure. Although no profound shifts in mesozooplankton were observed in Ushuaia Bay, eutrophication may have an impact in the future through its effect on primary producers.Fil: Berasategui, Anabela Anhi. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: LĂłpez Abbate, MarĂa Celeste. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: D'agostino, Valeria Carina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Centro Nacional PatagĂłnico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Presta, MarĂa Laura. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Biodiversidad y BiologĂa Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y BiologĂa Experimental y Aplicada; ArgentinaFil: Uibrig, RomĂĄn Armando. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: GarcĂa, Tami MailĂ©n. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Nahuelhual, Eugenia Gabriela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Chazarreta, Carlo Javier. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Dutto, MarĂa SofĂa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Garcia, Maximiliano DarĂo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Capitanio, Fabiana Lia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de Biodiversidad y BiologĂa Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y BiologĂa Experimental y Aplicada; ArgentinaFil: Hoffmeyer, Monica Susana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; Argentina. Universidad TecnolĂłgica Nacional. Facultad Regional BahĂa Blanca; Argentin