Enuresis: percepción y actitud en la población de nuestro país / Enuresis: Perception and attitude in population of our country

Objetivo Conocer la percepción y la actitud hacia la enuresis por parte de familias y cuidadores con el objetivo de establecer un plan terapéutico racional. Material y métodos Se realizó una encuesta de 25 preguntas a padres y madres mayores de 18años con al menos un hijo de entre 5 y 13años, manteniendo la representatividad nacional en términos de residencia, clase social y edad de los hijos. La recogida de datos se realizó en abril del 2021. Resultados Se obtuvieron datos de 501 encuestas de 626 enviadas, en su mayoría relativos a familias de clase social media de Andalucía, Cataluña y la Comunidad de Madrid. El 47,9% de los encuestados conocían la existencia de la enuresis, aunque únicamente el 23,8% sabían cuál era el término médico. Solo el 16,6% y el 9,6% recordaban que el/la pediatra o el/la enfermero/a, respectivamente, se hubieran referido en algún momento a la misma. Entre los participantes con algún conocimiento, las fuentes de información principales fueron los casos cercanos (36,6%), los medios de comunicación (31,1%) y el pediatra (27,8%). Los padres se preocuparían mucho (35,3%) o bastante (43,1%) ante un caso. Sin embargo, el nivel de conocimiento fue mayor y el grado de preocupación menor entre padres con hijos con enuresis respecto a los que no tenían casos en la familia. Conclusiones Mejorar el conocimiento de los padres sobre la enuresis y cambiar la percepción que tienen de la misma puede resultar de importancia para mejorar su atención y anticipar su resolución (AU)

Objective To know the perception and attitude towards enuresis from families and caregivers with the aim of establishing a rational therapeutic plan. Material and methods A 25-question survey was performed among parents over 18years old with at least a child between 5 and 13years old, maintaining national representativeness in terms of residence, social class and age of the children. Data collection was performed in April 2021. Results Data from 501 out of 626 sent surveys was obtained, mostly from middle-class families from Andalusia, Catalonia and the Community of Madrid. From all the participants, 47.9% knew about the existence of enuresis, although only 23.8% knew which was the medical term. Only 16.6% and 9.6% remembered that the pediatrician or the nurse, respectively, had referred to the condition at any time. Among the respondents with some knowledge about enuresis, their main information source were close cases (36.6%), media outlets (31.1%) and the pediatrician (27.8%). Parents would be very (35.3%) or somewhat (43.1%) worried in the event of an enuresis case. However, the level of knowledge was higher, and the level of concern was lower among parents with a child with enuresis in comparison to those without a case in their family. Conclusion Improving parent knowledge about enuresis and changing their perception towards this condition might be of importance to improve their attention and anticipate its resolution (AU)

[Enuresis: Perception and attitude in population of our country]. / Enuresis: percepción y actitud en la población de nuestro país.

OBJECTIVE: To know the perception and attitude towards enuresis from families and caregivers with the aim of establishing a rational therapeutic plan. MATERIAL AND METHODS: A 25-question survey was performed among parents over 18years old with at least a child between 5 and 13years old, maintaining national representativeness in terms of residence, social class and age of the children. Data collection was performed in April 2021. RESULTS: Data from 501 out of 626 sent surveys was obtained, mostly from middle-class families from Andalusia, Catalonia and the Community of Madrid. From all the participants, 47.9% knew about the existence of enuresis, although only 23.8% knew which was the medical term. Only 16.6% and 9.6% remembered that the pediatrician or the nurse, respectively, had referred to the condition at any time. Among the respondents with some knowledge about enuresis, their main information source were close cases (36.6%), media outlets (31.1%) and the pediatrician (27.8%). Parents would be very (35.3%) or somewhat (43.1%) worried in the event of an enuresis case. However, the level of knowledge was higher, and the level of concern was lower among parents with a child with enuresis in comparison to those without a case in their family. CONCLUSION: Improving parent knowledge about enuresis and changing their perception towards this condition might be of importance to improve their attention and anticipate its resolution.

Radiofrequency-assisted transection of the pancreas versus stapler in distal pancreatectomy: study protocol for a multicentric randomised clinical trial (TRANSPAIRE).

INTRODUCTION: To date, no pancreatic stump closure technique has been shown to be superior to any other in distal pancreatectomy. Although several studies have shown a trend towards better results in transection using a radiofrequency device (radiofrequency-assisted transection (RFT)), no randomised trial for this purpose has been performed to date. Therefore, we designed a randomised clinical trial, with the hypothesis that this technique used in distal pancreatectomies is superior in reducing clinically relevant postoperative pancreatic fistula (CR-POPF) than mechanical closures. METHODS AND ANALYSIS: TRANSPAIRE is a multicentre randomised controlled trial conducted in seven Spanish pancreatic centres that includes 112 patients undergoing elective distal pancreatectomy for any indication who will be randomly assigned to RFT or classic stapler transections (control group) in a ratio of 1:1. The primary outcome is the CR-POPF percentage. Sample size is calculated with the following assumptions: 5% one-sided significance level (α), 80% power (1-ß), expected POPF in control group of 32%, expected POPF in RFT group of 10% and a clinically relevant difference of 22%. Secondary outcomes include postoperative results, complications, radiological evaluation of the pancreatic stump, metabolomic profile of postoperative peritoneal fluid, survival and quality of life. Follow-ups will be carried out in the external consultation at 1, 6 and 12 months postoperatively. ETHICS AND DISSEMINATION: TRANSPAIRE has been approved by the CEIM-PSMAR Ethics Committee. This project is being carried out in accordance with national and international guidelines, the basic principles of protection of human rights and dignity established in the Declaration of Helsinki (64th General Assembly, Fortaleza, Brazil, October 2013), and in accordance with regulations in studies with biological samples, Law 14/2007 on Biomedical Research will be followed. We have defined a dissemination strategy, whose main objective is the participation of stakeholders and the transfer of knowledge to support the exploitation of activities. REGISTRATION DETAILS: ClinicalTrials.gov Registry (NCT04402346).

Effects of climate variation on bird escape distances modulate community responses to global change.

Climate and land use are rapidly changing environmental conditions. Behavioral responses to such global perturbations can be used to incorporate interspecific interactions into predictive models of population responses to global change. Flight initiation distance (FID) reflects antipredator behaviour defined as the distance at which an individual takes flight when approached by a human, under standardized conditions. This behavioural trait results from a balance between disturbance, predation risk, food availability and physiological needs, and it is related to geographical range and population trends in European birds. Using 32,145 records of flight initiation distances for 229 bird species during 2006-2019 in 24 European localities, we show that FIDs decreased with increasing temperature and precipitation, as expected if foraging success decreased under warm and humid conditions. Trends were further altered by latitude, urbanisation and body mass, as expected if climate effects on FIDs were mediated by food abundance and need, differing according to position in food webs, supporting foraging models. This provides evidence for a role of behavioural responses within food webs on how bird populations and communities are affected by global change.

Outcomes of an enhanced recovery after radical cystectomy program in a prospective multicenter study: compliance and key components for success.

OBJECTIVE: To investigate the effect of an Enhanced Recovery After Surgery (ERAS) program on complications and length of stay (LOS) after radical cystectomy (RC) and to assess if the number and type of components of ERAS play a key role on the decrease of surgical morbidity. MATERIALS AND METHODS: We analyzed the data of 277 patients prospectively recruited in 11 hospitals undergoing RC initially managed according to local practice (Group I) and later within an ERAS program (Group II). Two main outcomes were defined: 90-day complications rate and LOS. As secondary variables we studied 90-day mortality, 30-day readmission and transfusion rate. RESULTS: Patients in Group II had a higher use of ERAS measures (98.6%) than those in Group I (78.2%) (p < 0.05). Patients in Groups I and II experienced similar complications (70.5% vs. 66%, p = 0.42). LOS was not different between Groups I and II (12.5 and 14 days, respectively, p = 0.59). The risk of having any complication decreases for patients having more than 15 ERAS measures adopted [RR = 0.815; 95% confidence interval (CI) 0.667-0.996; p = 0.045]. Avoidance of transfusion and nasogastric tube, prevention of ileus, early ambulation and a fast uptake of a regular diet are independently associated with the absence of complications. CONCLUSIONS: Complications and LOS after RC were not modified by the introduction of an ERAS program. We hypothesize that at least 15 measures should be applied to maximize the benefit of ERAS.

A novel semi-robotized device for high-precision 18F-FDG-guided breast cancer biopsy / Un nuevo dispositivo semirrobotizado para biopsia de alta precisión guiada por la captación de 18F-FDG en el cáncer de mama

Purpose. To assess the 3D geometric sampling accuracy of a new PET-guided system for breast cancer biopsy (BCB) from areas within the tumour with high 18F-FDG uptake. Materials and methods. In the context of the European Union project MammoCare, a prototype semi-robotic stereotactic prototype BCB-device was incorporated into a dedicated high resolution PET-detector for breast imaging. The system consists of 2 stacked rings, each containing 12 plane detectors, forming a dodecagon with a 186mm aperture for 3D reconstruction (1mm3 voxel). A vacuum-assisted biopsy needle attached to a robot-controlled arm was used. To test the accuracy of needle placement, the needle tip was labelled with 18F-FDG and positioned at 78 target coordinates distributed over a 35mm×24mm×28mm volume within the PET-detector field-of-view. At each position images were acquired from which the needle positioning accuracy was calculated. Additionally, phantom-based biopsy proofs, as well as MammoCare images of 5 breast cancer patients, were evaluated for the 3D automated locating of 18F-FDG uptake areas within the tumour. Results. Needle positioning tests revealed an average accuracy of 0.5mm (range 0-1mm), 0.6mm (range 0-2mm), and 0.4mm (range 0-2mm) for the x/y/z-axes, respectively. Furthermore, the MammoCare system was able to visualize and locate small (<10mm) regions with high 18F-FDG uptake within the tumour suitable for PET-guided biopsy after being located by the 3D automated application. Conclusions. Accuracy testing demonstrated high-precision of this semi-automatic 3D PET-guided system for breast cancer core needle biopsy. Its clinical feasibility evaluation in breast cancer patients scheduled for neo-adjuvant chemotherapy will follow (AU)

Objetivo. Evaluar la precisión de un nuevo sistema de biopsia de mama (BM) guiado por PET que permite tomar muestras en áreas tumorales de alta captación de 18F-FDG en 3D con alta precisión geométrica. Materiales y métodos. El proyecto MammoCare financiado por la Unión Europea desarrolló un dispositivo de BM estereotáctica incorporado en un PET dedicado de alta resolución provisto de 2 anillos apilados con 12 detectores planos cada uno formando un dodecágono con una apertura de 186mm para la adquisición de PET en posición prona y reconstrucción 3D con vóxeles de 1mm3. El sistema utiliza agujas de biopsia asistida por vacío colocadas en un dispositivo robotizado. Su exactitud se estableció marcando con 18F-FDG la punta de la aguja en un objetivo de 35×24×28mm colocado dentro del campo visual del anillo PET. Se utilizaron 78 coordenadas realizando una adquisición por posición. Adicionalmente, se evaluó la localización 3D automatizada de las áreas de captación de 18F-FDG utilizando las imágenes de 5 pacientes con cáncer de mama. Resultados. Se estableció una precisión media de 0,5mm (rango 0-1mm); 0,6mm (rango 0-2mm) y 0,4mm (rango 0-2mm) respectivamente para los ejes x/y/z, en la colocación de la aguja. La aplicación 3D automatizada localizó múltiples regiones (<10mm) intratumorales con alta captación de 18F-FDG adecuadas para BM guiada por PET. Conclusión. El sistema de BM guiada por PET con localización semirrobotizada alcanzó alta precisión lo que permitirá evaluar su viabilidad clínica en pacientes con cáncer de mama programados para quimioterapia neoadyuvante (AU)

A novel semi-robotized device for high-precision 18F-FDG-guided breast cancer biopsy.

PURPOSE: To assess the 3D geometric sampling accuracy of a new PET-guided system for breast cancer biopsy (BCB) from areas within the tumour with high 18F-FDG uptake. MATERIALS AND METHODS: In the context of the European Union project MammoCare, a prototype semi-robotic stereotactic prototype BCB-device was incorporated into a dedicated high resolution PET-detector for breast imaging. The system consists of 2 stacked rings, each containing 12 plane detectors, forming a dodecagon with a 186mm aperture for 3D reconstruction (1mm3 voxel). A vacuum-assisted biopsy needle attached to a robot-controlled arm was used. To test the accuracy of needle placement, the needle tip was labelled with 18F-FDG and positioned at 78 target coordinates distributed over a 35mm×24mm×28mm volume within the PET-detector field-of-view. At each position images were acquired from which the needle positioning accuracy was calculated. Additionally, phantom-based biopsy proofs, as well as MammoCare images of 5 breast cancer patients, were evaluated for the 3D automated locating of 18F-FDG uptake areas within the tumour. RESULTS: Needle positioning tests revealed an average accuracy of 0.5mm (range 0-1mm), 0.6mm (range 0-2mm), and 0.4mm (range 0-2mm) for the x/y/z-axes, respectively. Furthermore, the MammoCare system was able to visualize and locate small (<10mm) regions with high 18F-FDG uptake within the tumour suitable for PET-guided biopsy after being located by the 3D automated application. CONCLUSIONS: Accuracy testing demonstrated high-precision of this semi-automatic 3D PET-guided system for breast cancer core needle biopsy. Its clinical feasibility evaluation in breast cancer patients scheduled for neo-adjuvant chemotherapy will follow.

Survey of hemostasis management and transfusion in liver transplantation.

OBJECTIVE: To determine the management of haemostasis and transfusion practice in the field of liver transplantation in Spain. METHODS: A questionnaire was developed for physicians in anaesthesiology of all centres performing liver transplantation in Spain. The information required made reference to the 12 months prior to its distribution, from January 1 to December 31, 2011. RESULTS: Data were collected from 24 centres in which liver transplantation is performed in Spain. Only 46% reported that they had protocols or practice guidelines for the management of haemostasis, and 83% of hospitals responded that they knew the percentage of transfused patients, but only 57% knew the mean transfusion. Regarding the degree of satisfaction with the management of haemostasis/coagulation, 50% said they were not satisfied. Thromboelastometry was used as an additional method of preoperative monitoring in only 8% of the centres and intra-operatively in one-third. Less than half (46%) of the centres performed preoperative correction of coagulation deficits based on conventional tests. The mean number of packed red cells used was ≤4 in 57% of centres. Consumption of fresh frozen plasma was highly variable, while 100% of centres consumed less than 4 pools of platelets per patient. CONCLUSIONS: There is a wide variability in the management of haemostasis and transfusion practice among Spanish centres. There are no guidelines or they are not widely used. The mean use of transfused blood products remain high. There was a decrease in centres using new methods of monitoring.

Antitumoral gene-based strategy involving nitric oxide synthase type III overexpression in hepatocellular carcinoma.

Hepatocellular carcinoma develops in cirrhotic liver. The nitric oxide (NO) synthase type III (NOS-3) overexpression induces cell death in hepatoblastoma cells. The study developed gene therapy designed to specifically overexpress NOS-3 in cultured hepatoma cells, and in tumors derived from orthotopically implanted tumor cells in fibrotic livers. Liver fibrosis was induced by CCl4 administration in mice. The first-generation adenoviruses were designed to overexpress NOS-3 or green fluorescent protein, and luciferase complementary DNA under the regulation of murine alpha-fetoprotein (AFP) and Rous Sarcoma Virus (RSV) promoters, respectively. Both adenovirus and Hepa 1-6 cells were used for in vitro and in vivo experiments. Adenoviruses were administered through the tail vein 2 weeks after orthotopic tumor cell implantation. AFP-NOS-3/RSV-luciferase increased oxidative-related DNA damage, p53, CD95/CD95L expression and caspase-8, -9 and -3 activities in cultured Hepa 1-6 cells. The increased expression of CD95/CD95L and caspase-8 activity was abolished by Nω-nitro-l-arginine methyl ester hydrochloride, p53 and CD95 small interfering RNA. AFP-NOS-3/RSV-luciferase adenovirus increased cell death markers, and reduced cell proliferation of established tumors in fibrotic livers. The increase of oxidative/nitrosative stress induced by NOS-3 overexpression induced DNA damage, p53, CD95/CD95L expression and cell death in hepatocellular carcinoma cells. The effectiveness of the gene therapy has been demonstrated in vitro and in vivo.

CD34+ circulating progenitor cells after different training programs.

Circulating progenitor cells (CPC) are bone marrow-derived cells that are mobilized into the circulation. While exercise is a powerful mediator of hematopoiesis, CPC levels increase, and reports of their activation after different types of exercise are contradictory. Moreover, few studies have compared the possible effects of different training programs on CPC concentrations. 43 physically active healthy male subjects (age 22±2.4 years) were assigned to 4 different training groups: aerobic, resistance, mixed and control. Except for the control group, all participants trained for 6 weeks. Peripheral blood samples were collected through an antecubital vein, and CPC CD34(+) was analyzed on different days: pre-training, post-training, and 3 weeks after finishing the training period. While no significant differences in CPC were observed either within or between the different training groups, there was a tendency towards higher values post-training and large intra- and intergroup dispersion. We detected an inverse linear relationship between pre-training values and % of CPC changes post-training (p<0.001). In the CPC values 3 weeks after training this inverse relationship was maintained, though to a lower extent (p<0.001). No changes in CPC CD34(+) were detected after 6 weeks of different training groups, or after 3 weeks of follow-up.

Intraventricular flow patterns and stasis in the LVAD-assisted heart.

Left ventricular assist device (LVAD) support disrupts the natural blood flow path through the heart, introducing flow patterns associated with thrombosis, especially in the presence of medical devices. The aim of this study was to quantitatively evaluate the flow patterns in the left ventricle (LV) of the LVAD-assisted heart, with a focus on alterations in vortex development and stasis. Particle image velocimetry of a LVAD-supported LV model was performed in a mock circulatory loop. In the Pre-LVAD flow condition, a vortex ring initiating from the LV base migrated toward the apex during diastole and remained in the LV by the end of ejection. During LVAD support, vortex formation was relatively unchanged although vortex circulation and kinetic energy increased with LVAD speed, particularly in systole. However, as pulsatility decreased and aortic valve opening ceased, a region of fluid stasis formed near the left ventricular outflow tract. These findings suggest that LVAD support does not substantially alter vortex dynamics unless cardiac function is minimal. The altered blood flow introduced by the LVAD results in stasis adjacent to the LV outflow tract, which increases the risk of thrombus formation in the heart.

Is "intra-operating room" thromboelastometry useful in liver transplantation? A case-control study in 303 patients.

Coagulation monitoring during liver transplantation (LT) is, even today, fundamental to reduce blood loss during surgery. Thromboelastometry (TEM) is a proven technique for controlling the various parameters that influence coagulation. However, there are no studies linking "intra-operating room" TEM (orTEM) with LT outcomes. We describe a case-control study in 303 liver graft recipients analyzing variables associated with operative complications and long-term LT outcomes. The results showed that orTEM reduced the use of blood products in patients with Model for End-Stage Liver Disease scores of ≥ 21, retransplantation, and high surgical difficulty and important intraoperative bleeding. In addition, results in survival and postoperative complications were better when orTEM was used. In conclusion, we confirm that use of orTEM is associated with less use of blood products and a lower rate of complications after LT.

Donor characteristics that are associated with survival in liver transplant recipients older than 70 years with grafts.

INTRODUCTION: The use of grafts from donors older than 70 years of age is increasing due to the decrease in the number of donors and the increase in waiting list patients. MATERIAL AND METHODS: We undertook a univariate and multivariate analysis of 980 adult recipients of whole liver grafts, 129 of them from donors aged 70 years or older. RESULTS: No differences were found in patient survival compared with recipients of younger grafts. There were no higher rates of rejection, vascular or biliary complications, postoperative bleeding, or infections, but older grafts were associated with graft dysfunction (P = .01) and a higher frequency of postoperative refractory ascites (P = .007), but without a greater need for retransplantation. As graft-associated factors, the joint presence in the donor of diabetes (P = .00; confidence interval [CI] = 0.04-0.117), hypertension (P = .00; CI = 0.22-0.39), and weight of more than 90 kg (P = .031; CI = 0.05-0.104) were suggestive of poor prognostic factors in recipient survival. Survival in hepatitis C virus (HCV) recipients or recipients aged older than 60 years was worse with donors aged older than 70 years, although not significantly so. With grafts from donors aged older than 80 years (n = 15), although patient survival rate was good (70% at 10 years), there was a higher rate of retransplantation (20%) and the early mortality rate was 13.3%. CONCLUSIONS: Use of grafts from donors aged older than 70 years is safe, with similar survival to patients with younger grafts. The appearance of initial dysfunction with prolonged ascites may be due to a delay in reaching a correct functionality, but was not associated with increased mortality, complications, or need for retransplantation. It should also be avoided in recipients older than 60 years or with HCV. Grafts older than 80 years were associated with a good long-term patient survival but at the expense of a higher rate of retransplantation. However, it helps to reduce the time on the waiting list and, thus, mortality. We noted decreased survival associated with donor hypertension, diabetes, and obesity, so these donors should be selected more rigorously.

Antitumor efficacy of mammalian target of rapamycin inhibitor therapy in liver transplant recipients with oncological disease: a case-control study.

INTRODUCTION: The reported incidences of de novo malignancy following orthotopic liver transplantation (OLT) are significantly greater than those in the general population. We have analyzed the efficacy of mammalian target of rapamycin inhibitor (mTORi) as immunosuppressant therapy in patients with de novo malignancies or those engrafted because of a primary liver cancer. METHODS: We performed a case-control study of patients with hepatocellular carcinoma (HCC; n = 119), cholangiocarcinoma (n = 1) or de novo malignancies (n = 73). Thirty-seven patients with these tumors were treated with mTORi, and 167, with calcineurin inhibitors (CNI). Switching to mTORi was performed progressively, withdrawing the CNI over 15 days, until obtaining levels of 5-10 ng/dL. RESULTS: No incidence of rejection, serious adverse events, or death was observed with an overall actuarial survival of 68.5% in the mTORi group versus 45.7% among the CNI group. Overall rates of tumor recurrence were 15.2% and 36.8%, respectively (P < .05). Among patients with HCC, survival was 100% of mTORi with and 61.5% among CNI patients, with tumor recurrence rates of 6.2% and 19.1%, respectively (P < .05). DISCUSSION: Surprising differences in survival and tumor recurrence rates were observed among the mTORi-treated group compared with controls. Switching from CNI to mTORi immunosuppressant therapy appeared to be safe. It seems to be reasonable to employ this strategy in liver transplant patients with primary hepatic or "de novo" neoplasms.

Results of liver transplantation with donors older than 70 years: a case-control study.

Older donors are a growing part of the total pool but no definite consensus exists on the age limit for their acceptance. This retrospective case-control unicenter study compared the outcomes of 72 orthotopic liver transplantations (OLTs) from April 1990 to April 2010 using donors older than 70 years versus 738 chronologically correlated OLTs performed with donors younger than 60 years. The percentage of refusal was greater among older than younger donors (48.2 vs 14.3%; P < .001). No difference was observed in mean cold ischemia times between older (370.5 minutes) versus younger groups (389.2 minutes). or in postoperative complications of rejection or renal insufficiency except for sepsis and mortality. Long-term survival was lower among transplant recipients from donors older than 70 years (P = .001) and these cases showed more blood requirements associated with prolonged cold ischemia (P = .02). Multivariate analysis revealed graft dysfunction, mortality, and reduced survival to be associated with donor weight and recipient MELD (Model for End-stage Liver Disease) (P < .05). Interestingly, the mortality related to hepatitis C virus recurrence was not greater among patients whose donors were older than 70. Septuagenarians' livers can be used safely, but careful donor and recipient evaluation are required to avoid additional risk factors.

Liver transplantation in patients with cryptogenic cirrhosis: long-term follow-up.

OBJECTIVE: The objective of this study was to evaluate long-term survival, histological diagnoses, and mobility of patients with cryptogenic cirrhosis (CC) treated with orthotopic liver transplantation (OLT). PATIENTS AND METHODS: We performed a retrospective analysis of 35 patients who underwent transplantation with CC among 800 OLT patients. There were no differences in gender, mean age of 47 years, average MELD (Model for End-stage Liver Disease) of 16, and hepatocellular carcinoma incidence (8%). RESULTS: In 28.6% of patients, the diagnosis of CC was wrong. There was no incidence of an acute rejection episode and a low incidence of complications, although the postoperative mortality rate was 20%, of chronic rejection was 25%, and recurrence of disease was 4%. Cumulative at 3-, 5-, and 10-year survivals were lower than the other OLT. Survival was lower in patients receiving suboptimal grafts. CONCLUSIONS: One of 3 patients who underwent transplantation for CC had a specific etiologic diagnosis. The chronic rejection rate and postoperative mortality rate were higher than other etiologies, and survivals at 5, 10, and 15 years were lower than other OLT.

Hormonal response of nestlings to predator calls.

Chicks of altricial birds may perceive predation risk by acoustic cues produced by predators. This capacity involves changes to a less conspicuous behavior to avoid being detected and predated. However, little is known about the physiological mechanisms underlying this capacity. Potential mechanisms may involve corticosterone and testosterone, two hormones related to begging, an acoustic signal, which could be used by predators to locate and predate the nest. However, given the species-specificity of this relationship, it is difficult to make particular predictions. We manipulated perceived risk of nest predation in the common blackbird (Turdus merula) and analyzed nestlings' plasma levels of these hormones to look for nest predation risk effects. Our experimental manipulation showed hormonal changes in response to nest predation risk. Chicks under a high risk of nest predation reduced their corticosterone plasma levels but increased their testosterone levels in comparison with nestlings exposed to a low nest predation risk. We explain our results as mechanisms to reduce begging activity and discuss them within the framework of hormonal modifications in developing animals. These findings highlight the importance of studying nest predation from the unusually considered chick perspective and underlined the benefits from including physiological variables in the study of predator-prey interactions.

Distribution of traction forces associated with shape changes during amoeboid cell migration.

Amoeboid motility results from the cyclic repetition of shape changes leading to periodic oscillations of the cell length (motility cycle). We analyze the dominant modes of shape change and their association to the traction forces exerted on the substrate using Principal Component Analysis (PCA) of time-lapse measurements of cell shape and traction forces in migrating Dictyostelium cells. Using wild-type cells (wt) as reference, we investigated Myosin II activity by studying Myosin II heavy chain null cells (mhcA-) and Myosin II essential light chain null cells (mlcE-). We found that wt, mlcE-and mhcA- cells utilize similar modes of shape changes during their motility cycle, although these shape changes are implemented at a slower pace in Myosin II null mutants. The number of dominant modes of shape changes is surprisingly few with only four modes accounting for 75% of the variance in all cases. The three principal shape modes are dilation/elongation, bending, and bulging of the front/back. The second mode, resulting from sideways protrusion/retraction, is associated to lateral asymmetries in the cell traction forces, and is significantly less important in mhcA- cells. These results indicate that the mechanical cycle of traction stresses and cell shape changes remains remarkably similar for all cell lines but is slowed down when myosin function is lost, probably due to a reduced control on the spatial organization of the traction stresses.