Body-axis organization in tetrapods: a model-system to disentangle the developmental origins of convergent evolution in deep time.

Convergent evolution is a central concept in evolutionary theory but the underlying mechanism has been largely debated since On the Origin of Species. Previous hypotheses predict that developmental constraints make some morphologies more likely to arise than others and natural selection discards those of the lowest fitness. However, the quantification of the role and strength of natural selection and developmental constraint in shaping convergent phenotypes on macroevolutionary timescales is challenging because the information regarding performance and development is not directly available. Accordingly, current knowledge of how embryonic development and natural selection drive phenotypic evolution in vertebrates has been extended from studies performed at short temporal scales. We propose here the organization of the tetrapod body-axis as a model system to investigate the developmental origins of convergent evolution over hundreds of millions of years. The quantification of the primary developmental mechanisms driving body-axis organization (i.e. somitogenesis, homeotic effects and differential growth) can be inferred from vertebral counts, and recent techniques of three-dimensional computational biomechanics have the necessary potential to reveal organismal performance even in fossil forms. The combination of both approaches offers a novel and robust methodological framework to test competing hypotheses on the functional and developmental drivers of phenotypic evolution and evolutionary convergence.

Acute Aortic Syndrome Revisited: JACC State-of-the-Art Review.

The purpose of this paper is to describe all available evidence on the distinctive features of a group of 4 life-threatening acute aortic pathologies gathered under the name of acute aortic syndrome (AAS). The epidemiology, diagnostic strategy, and management of these patients has been updated. The authors propose a new and simple diagnostic algorithm to support clinical decision making in cases of suspected AAS, thereby minimizing diagnostic delays, misdiagnoses, and unnecessary advanced imaging. AAS-related entities are reviewed, and a guideline to avoid imaging misinterpretation is provided. Centralization of patients with AAS in high-volume centers with high-volume surgeons is key to improving clinical outcomes. Thus, the role of multidisciplinary teams, an "aorta code" (streamlined emergent care pathway), and aortic centers in the management of these patients is boosted. A tailored patient treatment approach for each of these acute aortic entities is needed, and as such has been summarized. Finally, a set of prevention measures against AAS is discussed.

Independent origins of powered flight in paravian dinosaurs?

Feathered dinosaurs discovered during the last decades have illuminated the transition from land to air in these animals, underscoring a significant degree of experimentation in wing-assisted locomotion around the origin of birds. Such evolutionary experimentation led to lineages achieving either wing-assisted running, four-winged gliding, or membrane-winged gliding. Birds are widely accepted as the only dinosaur lineage that achieved powered flight, a key innovation for their evolutionary success. However, in a recent paper in Current Biology, Pei and colleagues1 disputed this view. They concluded that three other lineages of paravian dinosaurs (those more closely related to birds than to oviraptorosaurs) - Unenlagiinae, Microraptorinae and Anchiornithinae - could have evolved powered flight independently. While we praise the detailed phylogenetic framework of Pei and colleagues1 and welcome a new attempt to understand the onset of flight in dinosaurs, we here expose a set of arguments that significantly weaken their evidence supporting a multiple origin of powered flight. Specifically, we maintain that the two proxies used by Pei and colleagues1 to assess powered flight potential in non-avian paravians - wing loading and specific lift - fail to discriminate between powered flight (thrust generated by flapping) and passive flight (gliding).

Anatomy and Flight Performance of the Early Enantiornithine Bird Protopteryx fengningensis: Information from New Specimens of the Early Cretaceous Huajiying Formation of China.

The Early Cretaceous (∼131 Million Years Ago) Protopteryx fengningensis is one of the oldest and most primitive enantiornithine birds; however, knowledge of its anatomy has largely been limited to the succinct description of two specimens (holotype and paratype). This study describes two new specimens of P. fengningensis preserving most of the skeleton and plumage, and it therefore adds significantly to understanding the morphology of this important species and the character evolution of enantiornithine birds. The well-preserved plumage of these specimens also affords a quantitative assessment of the flight performance of P. fengningensis. Our aerodynamic considerations indicate that this early enantiornithine was capable of intermittent flight (bounding or flap-gliding), thus marking the earliest occurrence of such energy-saving aerial strategy. Anat Rec, 303:716-731, 2020. © 2019 American Association for Anatomy.

Osteohistology and Life History of the Basal Pygostylian, Confuciusornis sanctus.

More than a thousand specimens of Confuciusornis sanctus have been recovered from the Early Cretaceous Jehol Group of Northeastern China. Here, we investigate the bone microstructure of 33 long bones sampled from 14 C. sanctus specimens in an attempt to assess the life history patterns of this basal pygostylian bird. Analysis of the histology of various skeletal elements (femur, humerus, tibia, radius, and ulna) revealed differences in the histology of their bone walls. Based on the osteohistology, we coded the examined specimens into five histology age classes. We found that histological age was not strictly correlated with body size. The variability in the histology of multiple bones from single skeletons suggests differences in the growth rate of the skeleton in response to allometry, functional demands, and pathology. We show that although fibrolamellar bone is widespread across birds, the extent and duration of this rapid phase of bone deposition is highly variable. Comparisons among Mesozoic birds confirm that early ontogenetic growth was rapid, but that later post-hatching growth was strongly influenced by the ontogenetic age of the individual, body size, and local environment, as well as taxonomy. Our findings indicate that C. sanctus experienced rapid growth from early ontogeny until almost fully grown, and thereafter transitioned to slow, episodic growth (for at least 3-4 years) to reach skeletal maturity. Anat Rec, 303:949-962, 2020. © 2019 American Association for Anatomy.

Tuning the Interactions in Multiresponsive Complex Coacervate-Based Underwater Adhesives.

In this work, we report the systematic investigation of a multiresponsive complex coacervate-based underwater adhesive, obtained by combining polyelectrolyte domains and thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) units. This material exhibits a transition from liquid to solid but, differently from most reactive glues, is completely held together by non-covalent interactions, i.e., electrostatic and hydrophobic. Because the solidification results in a kinetically trapped morphology, the final mechanical properties strongly depend on the preparation conditions and on the surrounding environment. A systematic study is performed to assess the effect of ionic strength and of PNIPAM content on the thermal, rheological and adhesive properties. This study enables the optimization of polymer composition and environmental conditions for this underwater adhesive system. The best performance with a work of adhesion of 6.5 J/m2 was found for the complex coacervates prepared at high ionic strength (0.75 M NaCl) and at an optimal PNIPAM content around 30% mol/mol. The high ionic strength enables injectability, while the hydrated PNIPAM domains provide additional dissipation, without softening the material so much that it becomes too weak to resist detaching stress.

The earliest cut marks of Europe: a discussion on hominin subsistence patterns in the Orce sites (Baza basin, SE Spain).

Ancient evidence of human presence in Europe is recorded in several Early Pleistocene archaeopalaeontological sites from Spain, France and Italy. This is the case of Barranco León (BL) and Fuente Nueva-3 (FN-3), two localities placed near the town of Orce (depression of Baza and Guadix, SE Spain) and dated to ~1.4 Ma. At these sites, huge assemblages of Oldowan tools and evidence of defleshing, butchering and marrow processing of large mammal bones have been recovered together with a deciduous tooth of Homo sp. in the case of level BL-D. In this study, we: (i) describe in detail the anthropic marks found in the bone assemblages from these sites; (ii) analyse patterns of defleshment, butchery and marrow processing, based on the modifications identified in the cortical surface of the fossils; and (iii) discuss on the subsistence strategies of the first hominins that inhabited the European subcontinent during Early Pleistocene times.

Thermoresponsive Complex Coacervate-Based Underwater Adhesive.

Sandcastle worms have developed protein-based adhesives, which they use to construct protective tubes from sand grains and shell bits. A key element in the adhesive delivery is the formation of a fluidic complex coacervate phase. After delivery, the adhesive transforms into a solid upon an external trigger. In this work, a fully synthetic in situ setting adhesive based on complex coacervation is reported by mimicking the main features of the sandcastle worm's glue. The adhesive consists of oppositely charged polyelectrolytes grafted with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) chains and starts out as a fluid complex coacervate that can be injected at room temperature. Upon increasing the temperature above the lower critical solution temperature of PNIPAM, the complex coacervate transitions into a nonflowing hydrogel while preserving its volume-the water content in the material stays constant. The adhesive functions in the presence of water and bonds to different surfaces regardless of their charge. This type of adhesive avoids many of the problems of current underwater adhesives and may be useful to bond biological tissues.

[Uso de los valores de hormona paratiroidea intranodular obtenidos por punción con aguja fina como factor predictivo de hipoparatiroidismo posoperatorio]. / Use of intranodular parathyroid hormone values obtained by fine needle aspiration as a predictive factor of postoperative hypoparathyroidism.

OBJETIVO: Análisis de los valores de hormona paratiroidea (PTH) intranodular obtenidos por punción con aguja fina como factor predictivo de hipoparatiroidismo posoperatorio. MÉTODO: De los 157 pacientes a los que se realizó la medición de la PTH intranodular, se estudiaron 37 que fueron intervenidos quirúrgicamente, estableciendo 15 variables para analizar: edad, sexo, tiempo de evolución, tamaño, cirugía de tiroides asociada, tratamiento preoperatorio con calcimiméticos, litiasis renal, densitometría ósea, aclaramiento de creatinina, calcio y PTH preoperatorios, PTH determinada tras punción con aguja fina, descenso de la PTH intraoperatoria, calcio posoperatorio y malignidad de la tumoración. Estas se compararon con la prueba de ji al cuadrado o el test exacto de Fisher, siendo significativa una p < 0.05, construyéndose así un análisis de regresión logística. RESULTADOS: El uso de calcimiméticos previo a la cirugía, la PTH preoperatoria > 88 pg/dl, el calcio preoperatorio > 12 mg/dl, los valores de PTH intranodular > 2700 pg/dl, el descenso de la PTH intraoperatoria a < 15 pg/dl y el calcio posoperatorio < 8,5 mg/dl fueron variables independientes significativas en el análisis univariante (p < 0.05) para la predicción del hipoparatiroidismo posoperatorio. CONCLUSIONES: Los valores de PTH intranodular pueden predecir qué pacientes tienen mayor riesgo de sufrir un hipoparatiroidismo posoperatorio. Este factor debe tenerse en cuenta durante el estudio y el seguimiento de los pacientes para identificar precozmente posibles complicaciones. OBJECTIVE: To analize if parathyroid hormone (PTH) washout levels can be considered a predictive factor of postoperative hypoparathyroidism and determine its importance relative to other features already known as intraoperative PTH, Ca and PTH preoperative, and others. METHOD: Of the 157 patients to whom a fine needle aspiration (FNA) biopsy with intranodular parathyroid hormone level measurement was performed (washout PTH) 37 who underwent surgery were studied. 15 variables were taken into account when selecting patients for this study: age, gender, evolution length, size, associated thyroid surgery, preoperative treatment with calcimimetics, presence of renal lithiasis, bone densitometry alterations, creatine clearance, preoperative calcium and PTH levels, PTH scores obtained by fine needle aspiration, intraoperative PTH decrease, postoperative calcium levels and tumour malignancy. We compare the nominal values, using the Chi squared or the exact Fisher test, where p < 0.05 was considered statistically significant and perform a logistic regression analysis. RESULTS: The use of calcimimetics prior to surgery, the preoperative PTH level above 88 pg/dl, the preoperative calcium above 12 mg/dl, washout PTH above 2700 pg/dl, intraoperative PTH level decrease below 15 pg/dl, and postoperative calcium levels under 8.5 mg/dl were all independently significant variables in the univariant analysis (p < 0.05) in order to establish an early postoperative hypoparathyroidism. The rest of the variables were not statistically significative. CONCLUSION: The PTH washout levels can predict the appearance of postoperative hypoparathyroidism. This factor must be taken into account during the study and follow-up to identify possible complications and establish an adequate treatment on time.

A diminutive perinate European Enantiornithes reveals an asynchronous ossification pattern in early birds.

Fossils of juvenile Mesozoic birds provide insight into the early evolution of avian development, however such fossils are rare. The analysis of the ossification sequence in these early-branching birds has the potential to address important questions about their comparative developmental biology and to help understand their morphological evolution and ecological differentiation. Here we report on an early juvenile enantiornithine specimen from the Early Cretaceous of Europe, which sheds new light on the osteogenesis in this most species-rich clade of Mesozoic birds. Consisting of a nearly complete skeleton, it is amongst the smallest known Mesozoic avian fossils representing post-hatching stages of development. Comparisons between this new specimen and other known early juvenile enantiornithines support a clade-wide asynchronous pattern of osteogenesis in the sternum and the vertebral column, and strongly indicate that the hatchlings of these phylogenetically basal birds varied greatly in size and tempo of skeletal maturation.

Design and Evaluation of a Structural Reinforced Small Intestinal Submucosa Vascular Graft for Hemodialysis Access in a Porcine Model.

Synthetic vascular access for hemodialysis exhibits biological and mechanical material properties mismatch with the native vessels. These limitations prevent infiltration of endothelial cells and decrease grafts long-term patency, particularly in small diameter vessels. We aimed to design a curved structural reinforced small intestinal submucosa (SIS) vascular graft for hemodialysis access and to evaluate in a porcine animal model graft patency by Doppler ultrasonography, tissue remodeling by histology, and vascular wall Young's modulus after implantation by biaxial tensile test. Curved 4 mm inner diameter, 0.5 mm thickness, and 150 mm length SIS grafts were designed. Small intestinal submucosa vascular grafts were preliminary tested in vivo in a porcine animal model (n=3) constructing an arteriovenous fistula between the carotid artery and the jugular vein; GORE-TEX grafts were implanted as control. Small intestinal submucosa grafts remained patent 46 ± 7 days against the control, 30 ± 3 days. Histology showed thrombus formation on the lumen (80% to 100% surface area) of all explanted grafts. Small intestinal submucosa grafts exhibited neovascularization and endothelial cells alignment on the graft wall, indicating regeneration. Biaxial tensile tests demonstrated no significant differences in Young's moduli between SIS grafts (ECirc = 2.5 ± 1.0 MPa, ELong = 5.7 ± 2.6 MPa) and native artery (ECirc = 1.4 ± 0.8 MPa, ELong = 5.5 ± 1.1 MPa), indicating similar wall stiffness. This study proposes an innovative design of a tissue-engineered vascular graft for hemodialysis access that, besides its structural characteristics similar to those of current synthetic grafts, could enhance biological performance because of its composition.

Prevalence and genotype identification of Toxoplasma gondii in wild animals from southwestern Spain.

We used PCR to detect Toxoplasma gondii in the principal game species in southwestern Spain. We detected T. gondii in 32.2% of animals tested. Prevalences varied from 14.7% in wild boar (Sus scrofa) to 51.2% in red fox (Vulpes vulpes). The most prevalent genotype was type II (50.0%), followed by type III (20.6%) and type I (5.9%). Mixed infections (11.8%) were detected in wild boar (types I+III) and red fox (types II+III). Polymorphic strains (11.8%) were detected in several species. The high prevalence and the genetic variability shown could have implications for infection of farm animals and humans.

What elements of the informational, management, and relational continuity are associated with patient satisfaction with rehabilitation care and global rating change?

OBJECTIVE: To describe the quality of patients' continuity experiences in a population of outpatients receiving postacute rehabilitation care, and to check which elements and types of continuity most strongly determine their satisfaction with care and functional changes. DESIGN: Cross-sectional self-report survey. SETTING: Three postacute ambulatory centers in metropolitan areas. PARTICIPANTS: Outpatients (N=218; mean age ± SD, 38.5±11.7y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The questionnaire included experiences regarding aspects of informational (transference of information, accumulated knowledge), management (consistency and flexibility of care), and relational (established relation and consistency of provider) continuity, as well as questions concerning patients' sociodemographic characteristics, satisfaction with care, and global rating change. RESULTS: Respondents indicated more problems in terms of management and relational continuity than in informational continuity. For all patient groups, experiences regarding elements of management continuity (R(2)=15.3%-22.4%), followed by relational continuity (R(2)=14.3%-25.2%), explained most of the variance of satisfaction. Consistency and flexibility of care, together with an established relation, were the most determining elements of satisfaction. Experiences regarding elements of management continuity explained most of the variance of change (18.5%), and flexibility was the most decisive element. CONCLUSIONS: Patient satisfaction and functional changes are related with experiences in aspects of management continuity, where there is room for improvement. Measures of management continuity may be promising as indicators of continuity, and they should be prioritized.

Is patient satisfaction and perceived service quality with musculoskeletal rehabilitation determined by patient experiences?

OBJECTIVE: To assess the relationships between patient experiences and two overall evaluations - satisfaction and service quality - in outpatient rehabilitation settings. DESIGN: A cross-sectional, self-reported survey carried out in the year 2009. SETTING: Three outpatient rehabilitation units belonging to Spanish hospitals located in Barcelona, Madrid and Seville. SUBJECTS: Four hundred and sixty-five outpatients (response rate 90%) mean age 39.4 (SD = 11.9) years. MAIN MEASURES: Self-reported experiences on aspects of care, participants' perception of service quality, satisfaction with care, socio-demographic and health characteristics. RESULTS: Satisfaction and service quality were highly correlated (rho = 0.72, P< 0.001). Two multivariate logistic regression models using satisfaction and service quality (with adjusted R(2) 31.5% and 37.1%, respectively) indicated that patients' experiences and global rating of health improvement have more effect on those evaluations than socio-demographic characteristics. Mean satisfaction was 8.9 (SD = 1.2), and 88% of respondents described high service quality. However, nearly 25% of the respondents who reported high-quality evaluations also indicated a problem score of more than 50% in almost all aspects of care studied. CONCLUSIONS: Satisfaction and service quality provide a poor indicator of patients' experiences. Both are two proxies but distinct constructs in rehabilitation care. Besides, not all problems encountered by patients are equally important to them.

How do care-provider and home exercise program characteristics affect patient adherence in chronic neck and back pain: a qualitative study.

BACKGROUND: The aim of this study is to explore perceptions of people with chronic neck or low back pain about how characteristics of home exercise programs and care-provider style during clinical encounters may affect adherence to exercises. METHODS: This is a qualitative study consisting of seven focus groups, with a total of 34 participants presenting chronic neck or low back pain. The subjects were included if they were receiving physiotherapy treatment and were prescribed home-based exercises. RESULTS: Two themes emerged: home-based exercise programme conditions and care provider's style. In the first theme, the participants described their positive and negative experiences regarding time consumption, complexity and effects of prescribed exercises. In the second theme, participants perceived more bonding to prescribed exercises when their care provider presented knowledge about the disease, promoted feedback and motivation during exercise instruction, gave them reminders to exercise, or monitored their results and adherence to exercises. CONCLUSIONS: Our experiential findings indicate that patient's adherence to home-based exercise is more likely to happen when care providers' style and the content of exercise programme are positively experienced. These findings provide additional information to health care providers, by showing which issues should be considered when delivering health care to patients presenting chronic neck or back pain.

Predictive factors of adherence to frequency and duration components in home exercise programs for neck and low back pain: an observational study.

BACKGROUND: Evidence suggests that to facilitate physical activity sedentary people may adhere to one component of exercise prescriptions (intensity, duration or frequency) without adhering to other components. Some experts have provided evidence for determinants of adherence to different components among healthy people. However, our understanding remains scarce in this area for patients with neck or low back pain. The aims of this study are to determine whether patients with neck or low back pain have different rates of adherence to exercise components of frequency per week and duration per session when prescribed with a home exercise program, and to identify if adherence to both exercise components have distinct predictive factors. METHODS: A cohort of one hundred eighty-four patients with chronic neck or low back pain who attended physiotherapy in eight primary care centers were studied prospectively one month after intervention. The study had three measurement periods: at baseline (measuring characteristics of patients and pain), at the end of physiotherapy intervention (measuring characteristics of the home exercise program) and a month later (measuring professional behaviors during clinical encounters, environmental factors and self-efficacy, and adherence behavior). RESULTS: Adherence to duration per session (70.9% +/- 7.1) was more probable than adherence to frequency per week (60.7% +/- 7.0). Self-efficacy was a relevant factor for both exercise components (p < 0.05). The total number of exercises prescribed was predictive of frequency adherence (p < 0.05). Professional behaviors have a distinct influence on exercise components. Frequency adherence is more probable if patients received clarification of their doubts (adjusted OR: 4.1; p < 0.05), and duration adherence is more probable if they are supervised during the learning of exercises (adjusted OR: 3.3; p < 0.05). CONCLUSION: We have shown in a clinic-based study that adherence to exercise prescription frequency and duration components have distinct levels and predictive factors. We recommend additional study, and advise that differential attention be given in clinical practice to each exercise component for improving adherence.

Role of IL-10 promoter polymorphisms in the development of severe aorto-iliac occlusive disease.

Aortic severe occlusive disease (ASO) is a peripheral manifestation of atherosclerosis with an inflammatory component. Interleukin (IL)-10 is an anti-inflammatory cytokine that plays a key role in the development of atherosclerosis, promoting the stability of the atherosclerotic plaque. Several polymorphisms within the 5' region of the IL-10 gene have been related to altered transcriptional activity and protein levels. We aimed at studying two microsatellites, IL-10R and IL-10G, at -4 and -1.2 Kb, and three single nucleotide polymorphisms at positions -1082A/G, -819C/T and -592C/A in a collection of 94 ASO patients and 519 ethnically matched controls. Our results show that the IL-10 proximal promoter haplotype IL-10G*11/ -1082G/ -819C/ -592C is more frequent in ASO patients than in controls (28.7% vs 16% p = 0.003; OR = 2.12). Therefore, our data suggest a role of the IL-10 gene on ASO susceptibility.

Pravastatin increases the expression of the tissue inhibitor of matrix metalloproteinase-1 and the oncogene Bax in human aortic abdominal aneurysms.

The effect of pravastatin on matrix metalloproteinase-9 (MMP-9) and the level of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 was studied in explants of human abdominal aortic aneurysm (AAA) obtained from 13 patients. The effect of pravastatin on the apoptotic status of human AAA explants was also examined. Total MMP-9 content did not differ in human AAA explants incubated in vitro in the presence or absence of pravastatin (10-6 mol/L) for 48 h. TIMP-1 levels were significantly increased in pravastatin-incubated AAA explants, but TIMP-2 production was not modified by pravastatin. Western blot experiments showed that, whereas Bax expression was increased in pravastatin-incubated AAA explants, the expression of Bcl-2 was not modified. On the other hand, the ratio of the expression of Bax to Bcl-2, an apoptotic index, was not modified by pravastatin. In the human AAA explants, the increase in Bax expression, but not the increase in TIMP-1 expression elicited by pravastatin, was reversed by L-mevalonate, a downstream HMG-CoA reductase metabolite, suggesting that the expression of Bax and TIMP-1 followed HMG-CoA reductase-dependent and -independent pathways, respectively. In conclusion, pravastatin increases both TIMP-1 and Bax expression in human AAA explants without changes in either MMP-9 activity or the apoptotic status.

Fourier analysis of the generalized CMAC neural network.

THE CEREBELLAR MODEL ARTICULATION CONTROLLER (CMAC) IS A SIMPLE AND FAST NEURAL NETWORK: these characteristics have extended its successful applications, while the analysis of its representation capabilities, as for many other neural networks, did not follow a similar development.IN THIS ARTICLE WE DISCOVER THE CLOSE PARALLELISM BETWEEN THE REPRESENTATION OF A FUNCTION BY A GENERALIZED CMAC (GCMAC) AND NYQUIST SAMPLING THEORY: discussing the role of different parameters and components of the network according to this similarity. The consideration of a representative example shows how the parallelism can be used to design a GCMAC adapted to its particular application.