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Bilateral Hyperplasia of Mandibular Coronoid Processes in a Pediatric Patient. J Craniofac Surg 2024:00001665-990000000-01497. [PMID: 38709025 DOI: 10.1097/scs.0000000000010216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 03/11/2024] [Indexed: 05/07/2024] Open
Abstract
Langen Beck disease, a rare idiopathic disorder, causes enlarged coronoid processes of the mandible, leading to restricted oral opening and deteriorating health. This paper presents a 10-year-old boy's case with bilateral hyperplasia of the coronoid processes (HCP), diagnosed using cranial computed tomography, severely limiting oral opening to 18 mm. Treatment involved early intraoral coronoidectomy followed by physiotherapy, yielding immediate oral opening improvement without recurrence after 1 year. Surgical timing should consider age, disease severity, and progression risk. While HCP etiology lacks conclusive evidence, genetic mutations may explain cases without identifiable causes. This case underscores the significance of timely intervention for HCP to alleviate symptoms and improve long-term outcomes, emphasizing individualized treatment strategies.
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Invading new climates at what cost? Ontogenetic differences in the thermal dependence of metabolic rate in an invasive amphibian. J Therm Biol 2024; 121:103836. [PMID: 38604116 DOI: 10.1016/j.jtherbio.2024.103836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/30/2024] [Accepted: 02/27/2024] [Indexed: 04/13/2024]
Abstract
Global warming can either promote or constrain the invasive potential of alien species. In ectotherm invaders that exhibit a complex life cycle, success is inherently dependent on the capacity of each developmental stage to cope with environmental change. This is particularly relevant for invasive anurans, which disperse on land while requiring water for reproduction. However, it remains unknown how the different life stages respond in terms of energy expenditure under different climate change scenarios. We here quantified the oxygen uptake of frogs at rest (a proxy of the standard metabolic rate) in the aquatic phase (at the tadpole and climax, i.e. during metamorphosis, stages) and in the terrestrial phase (metamorphosed stage) at three environmental temperatures. To do so, we used marsh frogs (Pelophylax ridibundus), an amphibian with the largest invasive range within the palearctic realm and for which their adaptation to global warming might be key to their invasion success. Beyond an increase of metabolic rate with temperature, our data show variation in thermal adaptation across life stages and a higher metabolic cost during metamorphosis. These results suggest that the cost to shift habitat and face changes in temperature may be a constraint on the invasive potential of species with a complex life cycle which may be particularly vulnerable during metamorphosis.
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What makes a great invader? Anatomical traits as predictors of locomotor performance and metabolic rate in an invasive frog. J Exp Biol 2023; 226:jeb246717. [PMID: 37955111 DOI: 10.1242/jeb.246717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/07/2023] [Indexed: 11/14/2023]
Abstract
Invasive species are characterized by their ability to establish and spread in a new environment. In alien populations of anurans, dispersal and fitness-related traits such as endurance, burst performance and metabolism are key to their success. However, few studies have investigated inter-individual variation in these traits and more specifically have attempted to understand the drivers of variation in these traits. Associations of anatomical features may be excellent predictors of variation in performance and could be targets for selection or subject to trade-offs during invasions. In this study, we used marsh frogs (Pelophylax ridibundus), a species that has been introduced in many places outside its native range and which is now colonizing large areas of Western Europe. We first measured the inter-individual variation in resting metabolism, the time and distance they were able to jump until exhaustion, and their peak jump force, and then measured the mass of specific organs and lengths of body parts suspected to play a role in locomotion and metabolism. Among the 5000 bootstrap replicates on body size-corrected variables, our statistical models most often selected the stomach (75.42%), gonads (71.46%) and the kidneys (67.26%) as predictors of inter-individual variation in metabolism, and the gluteus maximus muscle (97.24%) mass was the most frequently selected predictor of jump force. However, endurance was poorly associated with the anatomical traits (R2distance=0.42, R2time=0.37). These findings suggest that selection on these predictors may lead to physiological changes that may affect the colonization, establishment and dispersal of these frogs.
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Profunda Artery Perforator Flap Tongue Reconstruction: An Effective and Safe Alternative to the Anterolateral Thigh Flap. Plast Reconstr Surg 2023:00006534-990000000-02027. [PMID: 37384852 DOI: 10.1097/prs.0000000000010890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
BACKGROUND The anterolateral thigh (ALT) perforator flap is a workhorse flap for tongue reconstruction. The authors present an alternative option using the profunda artery perforator (PAP) flap for glossectomy reconstruction compared to the ALT flap. METHODS A retrospective review was conducted of 65 patients who underwent subtotal or total glossectomy reconstruction between 2016 and 2020 (46 ALT vs. 19 PAP flaps). Flap volume was assessed using CT scans at two different time points. Quality of life and functional outcomes were measured using the MD Anderson Symptom Inventory for head and neck cancer (MDASI-HN). RESULTS Patients undergoing a PAP flap had significantly lower BMI compared to ALT flaps (22.7±5.0 vs. 25.8±5.1; p=0.014). Donor site and recipient site complications were similar as was the mean flap volume seven months after surgery (30.9% for ALT vs. 28.1% for PAP; p=0.93). Radiation and chemotherapy did not appear to have a significant effect on flap volume change over time. The most frequently reported high-severity items in MDASI-HN were swallowing/chewing and voice/speech for both cohorts. Patients who had reconstruction with a PAP flap had significantly better swallowing function (p=0.034). CONCLUSION Both the PAP and ALT flaps appear to be safe and effective choices for subtotal and total tongue reconstruction. The PAP flap can serve as an alternative donor site, especially in the setting of malnourished patients with thin lateral thigh thickness undergoing reconstruction of extensive glossectomy defects.
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May future climate change promote the invasion of the marsh frog? An integrative thermo-physiological study. Oecologia 2023:10.1007/s00442-023-05402-0. [PMID: 37351628 DOI: 10.1007/s00442-023-05402-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 06/07/2023] [Indexed: 06/24/2023]
Abstract
Climate change and invasive species are two major drivers of biodiversity loss and their interaction may lead to unprecedented further loss. Invasive ectotherms can be expected to tolerate temperature variation because of a broad thermal tolerance and may even benefit from warmer temperatures in their new ranges that better match their thermal preference. Multi-trait studies provide a valuable approach to elucidate the influence of temperature on the invasion process and offer insights into how climatic factors may facilitate or hinder the spread of invasive ectotherms. We here used marsh frogs, Pelophylax ridibundus, a species that is invading large areas of Western Europe but whose invasive potential has been underestimated. We measured the maximal and minimal temperatures to sustain physical activity, the preferred temperature, and the thermal dependence of their stamina and jumping performance in relation to the environmental temperatures observed in their invasive range. Our results showed that marsh frogs can withstand body temperatures that cover 100% of the annual temperature variation in the pond they live in and 77% of the observed current annual air temperature variation. Their preferred body temperature and performance optima were higher than the average temperature in their pond and the average air temperature experienced under the shade. These data suggest that invasive marsh frogs may benefit from a warmer climate. Broad thermal tolerances, combined with high thermal preferences and traits maximised at high temperatures, may allow this species to expand their activity period and colonise underexploited shaded habitat, thereby promoting their invasion success.
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Evaluating a Routine Immunity Score (RIS2020) to Predict Development of Severe Infection in Solid Organ Recipients. J Heart Lung Transplant 2023. [DOI: 10.1016/j.healun.2023.02.430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
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Shifts in the thermal dependence of locomotor performance across an altitudinal gradient in native populations of Xenopus laevis. Physiol Biochem Zool 2023. [DOI: 10.1086/725237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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Same-Admission Microvascular Maxillofacial Ballistic Trauma Reconstruction Using Virtual Surgical Planning: A Case Series and Systematic Review. Craniomaxillofac Trauma Reconstr 2022; 15:206-218. [PMID: 36081679 PMCID: PMC9446274 DOI: 10.1177/19433875211026432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/03/2023] Open
Abstract
Study Design Retrospective case series; systematic review. Objective It is unknown whether the use of virtual surgical planning (VSP) to facilitate same-admission microsurgical reconstruction of the mandible following acute maxillofacial ballistic trauma (MBT) is sufficient to achieve definitive reconstruction and functional occlusion. Methods A single-center retrospective analysis was conducted for patients who underwent microsurgical reconstruction of the mandible using VSP after acute MBT. The PubMed/MEDLINE, Embase, ScienceDirect, and Scopus databases were systematically reviewed using blinded screening. Studies were evaluated via thematic analysis. Results Five patients were treated by same-admission and microsurgical reconstruction of the mandible using VSP. We observed an average of 16.4 ± 9.1 days between initial presentation and reconstruction, an average length of stay of 51.6 ± 17.9 days, 6.2 ± 2.8 operations, and 1.6 ± 0.9 free flaps per patient. Four types and 8 total flaps were employed, most commonly the anterior lateral thigh flap (37.5%). Care yielded complete flap survival. Each patient experienced at least 1 minor complication. All patients achieved centric occlusion, oral nutrition, and an approximation of their baseline facial aesthetic. Follow up was 191.0 ± 183.9 weeks. Systematic review produced 8 articles that adhered to inclusion criteria. Consensus themes in the literature were found for clinical goal and function of VSP when practicing MBT reconstruction, yet disagreement was found surrounding optimal treatment timeline. Conclusions Same-admission microsurgical reconstruction after MBT is safe and effective to re-establish mandibular form and function. VSP did not delay reconstruction, given the need for preparation prior to definitive reconstruction.
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High habitat invasibility unveils the invasiveness potential of water frogs. Biol Invasions 2022. [DOI: 10.1007/s10530-022-02849-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Proteomics reveal the protective effects of chlorogenic acid on Enterococcus faecium Q233 in a simulated pro-oxidant colonic environment. Food Res Int 2022; 157:111464. [PMID: 35761697 DOI: 10.1016/j.foodres.2022.111464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/29/2022] [Accepted: 06/01/2022] [Indexed: 11/26/2022]
Abstract
Certain phytochemicals have been found to promote the beneficial effects of probiotic bacteria although the molecular mechanisms of such interactions are poorly understood. The objective of the present study was to evaluate the impact of the exposure to 0.5 mM chlorogenic acid (CA) on the redox status and proteome of Enterococcus faecium isolated from cheese and challenged with 2.5 mM hydrogen peroxide (H2O2). The bacterium was incubated in anaerobic conditions for 48 h at 37 °C. CA exposure led to a more intense oxidative stress and accretion of bacterial protein carbonyls than those induced by H2O2. The oxidative damage to bacterial proteins was even more severe in the bacterium treated with both CA and H2O2, yet, such combination led to a strengthening of the antioxidant defenses, namely, a catalase-like activity. The proteomic study indicated that H2O2 caused a decrease in energy supply and the bacterium responded by reinforcing the membrane and wall structures and counteracting the redox and pH imbalance. CA stimulated the accretion of proteins related to translation and transcription regulators, and hydrolases. This phytochemical was able to counteract certain proteomic changes induced by H2O2 (i.e. increase of ATP binding cassete (ABC) transporter complex) and cause the increase of Rex, a redox-sensitive protein implicated in controlling metabolism and responses to oxidative stress. Although this protection should be confirmed under in vivo conditions, such effects point to benefits in animals or humans affected by disorders in which oxidative stress plays a major role.
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Do muscle contractile properties drive differences in locomotor performance in invasive populations of Xenopus laevis in France? J Comp Physiol B 2020; 190:771-778. [PMID: 32955613 DOI: 10.1007/s00360-020-01310-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/31/2020] [Accepted: 09/09/2020] [Indexed: 11/28/2022]
Abstract
Jumping and swimming are key locomotor traits in frogs intimately linked to survival and dispersal. French populations of the frog Xenopus laevis from the invasion front are known to possess greater terrestrial locomotor endurance. Here, we tested whether individuals from the invasion front show differences in their muscle physiology that may underlie the observed whole-organism performance differences. We measured muscle contractile properties of the isolated gastrocnemius muscle in vitro, including isometric stress, activation and relaxation time, and work loop power output, both before and during a period of fatiguing contractions. We found that frogs from the centre of the range can produce tetanus force in their gastrocnemius muscle faster than animals from the periphery of the range, which could contribute to higher performance in one-off jumps. Yet, populations did not differ in muscle endurance. These results, coupled with previous work on this invasive population of Xenopus laevis, suggest that the greater stamina observed in individuals from the periphery may be more due to anatomical differences such as longer hind limbs and larger hearts along with potentially other as of yet untested physiological differences rather than differences in the mechanical properties of skeletal muscle.
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Vesicovaginal Fistula Repair by Modified Martius Flap: A Step-by-Step Surgical Technique Video. Ann Surg Oncol 2020; 28:1002-1006. [PMID: 32797377 DOI: 10.1245/s10434-020-09020-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/25/2020] [Indexed: 01/09/2023]
Abstract
BACKGROUND Fistula repair in the perineal region represents a major challenge for surgeons. It is important for the medical community to facilitate and disclose these techniques. OBJECTIVE The aim of this article was to show a stepwise approach for a direct repair and use of a Martius flap for a vesicovaginal fistula. METHODS We show a single case performed in a patient who presented with a vesicovaginal fistula diagnosed after surgery, which did not respond to conservative management. The procedure consists of the following steps: intraoperative cystoscopy, anatomical direct repair of the fistulous tract between the bladder and vagina, and modified Martius flap. CONCLUSIONS Martius flap is a repair technique used for complex fistula in the perineal region. It is a simple, safe, and reproducible procedure with good long-term functional and esthetic results.
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Genetic diversity, Population Genetic Structure and Conservation Management of Spanish Verata Goat Breed. Small Rumin Res 2020. [DOI: 10.1016/j.smallrumres.2020.106106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Rapid Shifts in the Temperature Dependence of Locomotor Performance in an Invasive Frog, Xenopus laevis, Implications for Conservation. Integr Comp Biol 2020; 60:456-466. [DOI: 10.1093/icb/icaa010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Temperature is a critical abiotic factor impacting all aspects of the biology of organisms, especially in ectotherms. As such, it is an important determinant of the potential invasive ability of organisms and may limit population expansion unless organisms can physiologically respond to changes in temperature either through plasticity or by adapting to their novel environment. Here, we studied the African clawed frog, Xenopus laevis, which has become invasive on a global scale. We compared adults from an invasive population of western France with individuals from two populations in the native range in South Africa. We measured the thermal dependence of locomotor performance in adults given its relevance to dispersal, predator escape, and prey capture. Our results show significant differences in the limits of the 80% performance breadth interval for endurance with the French population showing a left shift in its limits congruent with the colder climate experienced in France. The French invasive population was introduced only about 40 years ago suggesting a rapid shift in the thermal physiology. Given that all individuals were acclimated under laboratory conditions at 23°C for 2 months this suggests that the invasive frogs have adapted to their new environment. These data may allow the refinement of physiologically informed species distribution models permitting better estimates of future ranges at risk of invasion.
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Reverse Janssen Effect in Narrow Granular Columns. PHYSICAL REVIEW LETTERS 2020; 124:128002. [PMID: 32281839 DOI: 10.1103/physrevlett.124.128002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 01/28/2020] [Accepted: 02/20/2020] [Indexed: 06/11/2023]
Abstract
When grains are added to a cylinder, the weight at the bottom is smaller than the total weight of the column, which is partially supported by the lateral walls through frictional interactions with the grains. This is known as the Janssen effect. Via a combined experimental and numerical investigation, here we demonstrate a reverse Jansen effect whereby the fraction of the weight supported by the base overcomes one. We characterize the dependence of this phenomenon on the various control parameters involved, rationalize the physical process causing the emergence of the compressional frictional forces responsible for the anomaly, and introduce a model to reproduce our findings. Contrary to prior assumptions, our results demonstrate that the constitutive relation on a material element can depend on the applied stress.
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Parasitics Impact on the Performance of Rectifier Circuits in Sensing RF Energy Harvesting. SENSORS 2019; 19:s19224939. [PMID: 31766171 PMCID: PMC6891323 DOI: 10.3390/s19224939] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 11/16/2022]
Abstract
This work presents some accurate guidelines for the design of rectifier circuits in radiofrequency (RF) energy harvesting. New light is shed on the design process, paying special attention to the nonlinearity of the circuits and the modeling of the parasitic elements. Two different configurations are tested: a Cockcroft–Walton multiplier and a half-wave rectifier. Several combinations of diodes, capacitors, inductors and loads were studied. Furthermore, the parasitics that are part of the circuits were modeled. Thus, the most harmful parasitics were identified and studied in depth in order to improve the conversion efficiency and enhance the performance of self-sustaining sensing systems. The experimental results show that the parasitics associated with the diode package and the via holes in the PCB (Printed Circuit Board) can leave the circuits inoperative. As an example, the rectifier efficiency is below 5% without considering the influence of the parasitics. On the other hand, it increases to over 30% in both circuits after considering them, twice the value of typical passive rectifiers.
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Allocation trade-offs impact organ size and muscle architecture in an invasive population of Xenopus laevis in Western France. J Anat 2019; 235:1057-1064. [PMID: 31373390 DOI: 10.1111/joa.13063] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2019] [Indexed: 11/28/2022] Open
Abstract
Invasive species are a global scourge and often negatively impact native species. Understanding the expansion and dispersal limits of these species is essential. As previous studies have demonstrated increased locomotor performance for populations at the edge of the range of expanding populations, studies of locomotion including the anatomical and physiological traits underlying dispersal capacity are of interest. We focus here on an invasive population of Xenopus laevis introduced in France nearly forty years ago. Previous studies have demonstrated differences in mobility between populations from the centre and the edge of the invasive range, with individuals from the range edge possessing a higher endurance capacity. We test here whether range-edge frogs show anatomical differences in organs or muscles underlying these observed differences of performance. We dissected 10 males and 10 females from central and range-edge sites (40 animals in total) and measured the mass of their organs and the mass, the length, and the physiological cross-sectional area (PCSA) of 28 hind limb muscles. Our results show anatomical differences with individuals from the range edge possessing heavier, longer and more forceful muscles. Moreover, females from the range edge had a heavier heart but lighter stomach than those of the centre of the range. Future studies comparing the morphology between native and invasive populations in other regions or for other species will be especially insightful to better understand the possible adaptive changes in invasive populations and the limits on dispersal capacity.
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RF Energy Harvesting System Based on an Archimedean Spiral Antenna for Low-Power Sensor Applications. SENSORS 2019; 19:s19061318. [PMID: 30884791 PMCID: PMC6471814 DOI: 10.3390/s19061318] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/04/2019] [Accepted: 03/13/2019] [Indexed: 11/22/2022]
Abstract
This paper presents a radiofrequency (RF) energy harvesting system based on an ultrawideband Archimedean spiral antenna and a half-wave Cockcroft-Walton multiplier circuit. The antenna was proved to operate from 350 MHz to 16 GHz with an outstanding performance. With its use, radio spectrum measurements were carried out at the Telecommunication Engineering School (Universidad Politécnica de Madrid) to determine the power level of the ambient signals in two different scenarios: indoors and outdoors. Based on these measurements, a Cockcroft-Walton multiplier and a lumped element matching network are designed to operate at 800 MHz and 900 MHz frequency bands. To correct the frequency displacement in the circuit, a circuit model is presented that takes into account the different parasitic elements of the components and the PCB. With an input power of 0 dBm, the manufactured circuit shows a rectifying efficiency of 30%. Finally, a test is carried out with the full RF energy harvesting system to check its correct operation. Thus, the RF system is placed in front of a transmitting Vivaldi antenna at a distance of 50 cm. The storage capacitor has a charge of over 1.25 V, which is enough to run a temperature sensor placed as the load to be supplied. This demonstrates the validity of the RF energy harvesting system for low-power practical applications.
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Acclimation temperature effects on locomotor traits in adult aquatic anurans ( X. tropicalis and X. laevis) from different latitudes: possible implications for climate change. CONSERVATION PHYSIOLOGY 2019; 7:coz019. [PMID: 31139411 PMCID: PMC6528024 DOI: 10.1093/conphys/coz019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 03/06/2019] [Accepted: 04/04/2019] [Indexed: 05/11/2023]
Abstract
Climate change is in part responsible for the 70% decline in amphibian species numbers worldwide. Although temperature is expected to impact whole-organism performance in ectotherms, reversible thermal acclimation has been suggested as a mechanism that may buffer responses to abrupt temperature changes. Here, we test for an effect of acclimation on locomotor performance traits (jump force and stamina) in adults of two predominantly aquatic and closely related frog species from different climatic regions, Xenopus tropicalis (tropical) and Xenopus laevis (temperate). We find significant effects of acclimation temperature on exertion capacity and for jump force in X. tropicalis but no effect of acclimation temperature on burst performance in X. laevis. Our results suggest that the two locomotor performance traits measured are differentially impacted by acclimation temperature in X. tropicalis. Our results further support the hypothesis that lower-latitude ectotherms might have greater acclimation capacity than high-latitude ones. Finally, our results highlight the importance of investigating multiple performance traits when evaluating how animals may cope with changes in temperature. Further work is required to evaluate the potential for acclimation in mitigating the negative impacts of climate change on amphibian populations.
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Turing-Hopf patterns on growing domains: The torus and the sphere. J Theor Biol 2018; 481:136-150. [PMID: 30266461 DOI: 10.1016/j.jtbi.2018.09.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/18/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
Abstract
This paper deals with the study of spatial and spatio-temporal patterns in the reaction-diffusion FitzHugh-Nagumo model on growing curved domains. This is carried out on two exemplar cases: a torus and a sphere. We compute bifurcation boundaries for the homogeneous steady state when the homogeneous system is monostable. We exhibit Turing and Turing-Hopf bifurcations, as well as additional patterning outside of these bifurcation regimes due to the multistability of patterned states. We consider static and growing domains, where the growth is slow, isotropic, and exponential in time, allowing for a simple analytical calculation of these bifurcations in terms of model parameters. Numerical simulations allow us to discuss the role played by the growth and the curvature of the domains on the pattern selection on the torus and the sphere. We demonstrate parameter regimes where the linear theory can successfully predict the kind of pattern (homogeneous and heterogeneous oscillations and stationary spatial patterns) but not their detailed nonlinear structure. We also find parameter regimes where the linear theory fails, such as Hopf regimes which give rise to spatial patterning (depending on geometric details), where we suspect that multistability plays a key role in the departure from homogeneity. Finally we also demonstrate effects due to the evolution of nonuniform patterns under growth, suggesting important roles for growth in reaction-diffusion systems beyond modifying instability regimes.
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Abstract
Cooperation is a central mechanism for evolution. It consists of an individual paying a cost in order to benefit another individual. However, natural selection describes individuals as being selfish and in competition among themselves. Therefore explaining the origin of cooperation within the context of natural selection is a problem that has been puzzling researchers for a long time. In the paradigmatic case of the Prisoner's Dilemma (PD), several schemes for the evolution of cooperation have been proposed. Here we introduce an extension of the Replicator Equation (RE), called the Optimal Replicator Equation (ORE), motivated by the fact that evolution acts not only at the level of individuals of a population, but also among competing populations, and we show that this new model for natural selection directly leads to a simple and natural rule for the emergence of cooperation in the most basic version of the PD. Contrary to common belief, our results reveal that cooperation can emerge among selfish individuals because of selfishness itself: if the final reward for being part of a society is sufficiently appealing, players spontaneously decide to cooperate.
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Ghost ileostomy in advanced ovarian cancer. Gynecol Oncol 2017; 147:488. [DOI: 10.1016/j.ygyno.2017.08.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 08/10/2017] [Accepted: 08/16/2017] [Indexed: 11/30/2022]
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Testing the hypothesis that biological modularity is shaped by adaptation: Xylem in theBursera simarubaclade of tropical trees. Evol Dev 2017; 19:111-123. [DOI: 10.1111/ede.12225] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
Spatial affine registration of brain images to a common template is usually performed as a preprocessing step in intersubject and intrasubject comparison studies, computer-aided diagnosis, region of interest selection and brain segmentation in tomography. Nevertheless, it is not straightforward to build a template of [123I]FP-CIT SPECT brain images because they exhibit very low intensity values outside the striatum. In this work, we present a procedure to automatically build a [123I]FP-CIT SPECT template in the standard Montreal Neurological Institute (MNI) space. The proposed methodology consists of a head voxel selection using the Otsu's method, followed by a posterization of the source images to three different levels: background, head, and striatum. Analogously, we also design a posterized version of a brain image in the MNI space; subsequently, we perform a spatial affine registration of the posterized source images to this image. The intensity of the transformed images is normalized linearly, assuming that the histogram of the intensity values follows an alpha-stable distribution. Lastly, we build the [123I]FP-CIT SPECT template by means of the transformed and normalized images. The proposed methodology is a fully automatic procedure that has been shown to work accurately even when a high-resolution magnetic resonance image for each subject is not available.
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A Turing–Hopf Bifurcation Scenario for Pattern Formation on Growing Domains. Bull Math Biol 2016; 78:1410-49. [DOI: 10.1007/s11538-016-0189-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 06/13/2016] [Indexed: 10/21/2022]
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Abstract
Clinical processing of event-related potentials (ERPs) requires a precise synchrony between the stimulation and the acquisition units that are guaranteed by means of a physical link between them. This precise synchrony is needed since temporal misalignments during trial averaging can lead to high deviations of peak times, thus causing error in diagnosis or inefficiency in classification in brain-computer interfaces (BCIs). Out of the laboratory, mobile EEG systems and BCI headsets are not provided with the physical link, thus being inadequate for acquisition of ERPs. In this study, we propose a method for the asynchronous detection of trials onset from raw EEG without physical links. We validate it with a BCI application based on the dichotic listening task. The user goal was to attend the cued auditory message and to report three keywords contained in it while ignoring the other message. The BCI goal was to detect the attended message from the analysis of auditory ERPs. The rate of successful onset detection in both synchronous (using the real onset) and asynchronous (blind detection of trial onset from raw EEG) was 73% with a synchronization error of less than 1[Formula: see text]ms. The level of synchronization provided by this proposal would allow home-based acquisition of ERPs with low cost BCI headsets and any media player unit without physical links between them.
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Analysis of beamforming for improving the energy efficiency in wireless sensor networks with metaheuristics. PROGRESS IN ARTIFICIAL INTELLIGENCE 2016. [DOI: 10.1007/s13748-016-0087-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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28
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Intensity normalization in the analysis of functional DaTSCAN SPECT images: The α-stable distribution-based normalization method vs other approaches. Neurocomputing 2015. [DOI: 10.1016/j.neucom.2014.01.080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Real time QRS detection based on M-ary likelihood ratio test on the DFT coefficients. PLoS One 2014; 9:e110629. [PMID: 25356628 PMCID: PMC4214710 DOI: 10.1371/journal.pone.0110629] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 09/16/2014] [Indexed: 12/04/2022] Open
Abstract
This paper shows an adaptive statistical test for QRS detection of electrocardiography (ECG) signals. The method is based on a M-ary generalized likelihood ratio test (LRT) defined over a multiple observation window in the Fourier domain. The motivations for proposing another detection algorithm based on maximum a posteriori (MAP) estimation are found in the high complexity of the signal model proposed in previous approaches which i) makes them computationally unfeasible or not intended for real time applications such as intensive care monitoring and (ii) in which the parameter selection conditions the overall performance. In this sense, we propose an alternative model based on the independent Gaussian properties of the Discrete Fourier Transform (DFT) coefficients, which allows to define a simplified MAP probability function. In addition, the proposed approach defines an adaptive MAP statistical test in which a global hypothesis is defined on particular hypotheses of the multiple observation window. In this sense, the observation interval is modeled as a discontinuous transmission discrete-time stochastic process avoiding the inclusion of parameters that constraint the morphology of the QRS complexes.
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Complex groundwater flow systems as traveling agent models. PeerJ 2014; 2:e557. [PMID: 25337455 PMCID: PMC4203025 DOI: 10.7717/peerj.557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 08/12/2014] [Indexed: 11/20/2022] Open
Abstract
Analyzing field data from pumping tests, we show that as with many other natural phenomena, groundwater flow exhibits complex dynamics described by 1/f power spectrum. This result is theoretically studied within an agent perspective. Using a traveling agent model, we prove that this statistical behavior emerges when the medium is complex. Some heuristic reasoning is provided to justify both spatial and dynamic complexity, as the result of the superposition of an infinite number of stochastic processes. Even more, we show that this implies that non-Kolmogorovian probability is needed for its study, and provide a set of new partial differential equations for groundwater flow.
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Regions of interest computed by SVM wrapped method for Alzheimer's disease examination from segmented MRI. Front Aging Neurosci 2014; 6:20. [PMID: 24634656 PMCID: PMC3929832 DOI: 10.3389/fnagi.2014.00020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 02/02/2014] [Indexed: 01/26/2023] Open
Abstract
Accurate identification of the most relevant brain regions linked to Alzheimer's disease (AD) is crucial in order to improve diagnosis techniques and to better understand this neurodegenerative process. For this purpose, statistical classification is suitable. In this work, a novel method based on support vector machine recursive feature elimination (SVM-RFE) is proposed to be applied on segmented brain MRI for detecting the most discriminant AD regions of interest (ROIs). The analyses are performed both on gray and white matter tissues, achieving up to 100% accuracy after classification and outperforming the results obtained by the standard t-test feature selection. The present method, applied on different subject sets, permits automatically determining high-resolution areas surrounding the hippocampal area without needing to divide the brain images according to any common template.
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A selection criterion for patterns in reaction-diffusion systems. Theor Biol Med Model 2014; 11:7. [PMID: 24476200 PMCID: PMC3925790 DOI: 10.1186/1742-4682-11-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/21/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alan Turing's work in Morphogenesis has received wide attention during the past 60 years. The central idea behind his theory is that two chemically interacting diffusible substances are able to generate stable spatial patterns, provided certain conditions are met. Ever since, extensive work on several kinds of pattern-generating reaction diffusion systems has been done. Nevertheless, prediction of specific patterns is far from being straightforward, and a great deal of interest in deciphering how to generate specific patterns under controlled conditions prevails. RESULTS Techniques allowing one to predict what kind of spatial structure will emerge from reaction-diffusion systems remain unknown. In response to this need, we consider a generalized reaction diffusion system on a planar domain and provide an analytic criterion to determine whether spots or stripes will be formed. Our criterion is motivated by the existence of an associated energy function that allows bringing in the intuition provided by phase transitions phenomena. CONCLUSIONS Our criterion is proved rigorously in some situations, generalizing well-known results for the scalar equation where the pattern selection process can be understood in terms of a potential. In more complex settings it is investigated numerically. Our work constitutes a first step towards rigorous pattern prediction in arbitrary geometries/conditions. Advances in this direction are highly applicable to the efficient design of Biotechnology and Developmental Biology experiments, as well as in simplifying the analysis of morphogenetic models.
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33
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Affine registration of [123I]FP-CIT SPECT brain images. Stud Health Technol Inform 2014; 207:65-73. [PMID: 25488212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work, we perform a comparison between the spatial normalization of [123I]FP-CIT SPECT brain images when a FP-CIT SPECT and a MRI template are used. A 12-parameters affine registration model is calculated by the optimization of a sum of squares cost function. When the images are registered to a FP-CIT template, the intersubject variation is found to be lower than when the MRI template is used, specially in the striatum, which is the most relevant part of the brain in FP-CIT SPECT brain images.
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Statistical significance in the selection of the regions of interest for Parkinson brain image processing. Stud Health Technol Inform 2014; 207:19-26. [PMID: 25488207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This paper presents the analysis of the statistical significance in the selection of the ROI for the discriminant analysis of brain images to identify Parkinson patients or subjects without any pathology. The particular features and brain functional patterns of the Parkinson's disease cause that there are regions that conveniently reveal the presence of the pathology, in this case mainly the striatum region. The selection of the brain mask makes incidence in two main aspects: the selection of the region of interest (striatum and surrounding area) for the analysis, but also the selection of the region without significance, which is the reference area for the intensity normalization, previous to the analysis. This work studies the statistical significance in the selection of ROIs in 3D brain images for Parkinson, depending on the objective to be achieved in the posterior analysis process.
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Amino acid determination in some edible Mexican insects. Amino Acids 2013; 9:161-73. [PMID: 24178816 DOI: 10.1007/bf00805837] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/1993] [Accepted: 01/18/1995] [Indexed: 11/29/2022]
Abstract
The amino acid contents of edible insects from different provinces of Mexico and reference proteins were analysed by reversed-phase high-performance liquid chromatography and ion exchange chromatography. The insect amino acid contents were higher than the adult requirements indicated by the WHO/FAO pattern.
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Space-time dynamics of Stem Cell Niches: a unified approach for Plants. J Integr Bioinform 2013. [DOI: 10.1515/jib-2013-219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Summary Many complex systems cannot be analyzed using traditional mathematical tools, due to their irreducible nature. This makes it necessary to develop models that can be implemented computationally to simulate their evolution. Examples of these models are cellular automata, evolutionary algorithms, complex networks, agent-based models, symbolic dynamics and dynamical systems techniques.We review some representative approaches to model the stem cell niche in Arabidopsis thaliana and the basic biological mechanisms that underlie its formation and maintenance. We propose a mathematical model based on cellular automata for describing the space-time dynamics of the stem cell niche in the root. By making minimal assumptions on the cell communication process documented in experiments, we classify the basic developmental features of the stem-cell niche, including the basic structural architecture, and suggest that they could be understood as the result of generic mechanisms given by short and long range signals. This could be a first step in understanding why different stem cell niches share similar topologies, not only in plants. Also the fact that this organization is a robust consequence of the way information is being processed by the cells and to some extent independent of the detailed features of the signaling mechanism.
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NMF-SVM based CAD tool applied to functional brain images for the diagnosis of Alzheimer's disease. IEEE TRANSACTIONS ON MEDICAL IMAGING 2012; 31:207-216. [PMID: 21914569 DOI: 10.1109/tmi.2011.2167628] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This paper presents a novel computer-aided diagnosis (CAD) technique for the early diagnosis of the Alzheimer's disease (AD) based on nonnegative matrix factorization (NMF) and support vector machines (SVM) with bounds of confidence. The CAD tool is designed for the study and classification of functional brain images. For this purpose, two different brain image databases are selected: a single photon emission computed tomography (SPECT) database and positron emission tomography (PET) images, both of them containing data for both Alzheimer's disease (AD) patients and healthy controls as a reference. These databases are analyzed by applying the Fisher discriminant ratio (FDR) and nonnegative matrix factorization (NMF) for feature selection and extraction of the most relevant features. The resulting NMF-transformed sets of data, which contain a reduced number of features, are classified by means of a SVM-based classifier with bounds of confidence for decision. The proposed NMF-SVM method yields up to 91% classification accuracy with high sensitivity and specificity rates (upper than 90%). This NMF-SVM CAD tool becomes an accurate method for SPECT and PET AD image classification.
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39
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Principal component analysis-based techniques and supervised classification schemes for the early detection of Alzheimer's disease. Neurocomputing 2011. [DOI: 10.1016/j.neucom.2010.06.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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40
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Feature selection using factor analysis for Alzheimer's diagnosis using 18F-FDG PET images. Med Phys 2011; 37:6084-95. [PMID: 21158320 DOI: 10.1118/1.3488894] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE This article presents a computer-aided diagnosis technique for improving the accuracy of the early diagnosis of Alzheimer's disease (AD). Two hundred and ten 18F-FDG PET images from the ADNI initiative [52 normal controls (NC), 114 mild cognitive impairment (MCI), and 53 AD subjects] are studied. METHODS The proposed methodology is based on the selection of voxels of interest using the t-test and a posterior reduction of the feature dimension using factor analysis. Factor loadings are used as features for three different classifiers: Two multivariate Gaussian mixture model, with linear and quadratic discriminant function, and a support vector machine with linear kernel. RESULTS An accuracy rate up to 95% when NC and AD are considered and an accuracy rate up to 88% and 86% for NC-MCI and NC-MCI,AD, respectively, are obtained using SVM with linear kernel. CONCLUSIONS Results are compared to the voxel-as-features and a PCA- based approach and the proposed methodology achieves better classification performance.
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Projecting independent components of SPECT images for computer aided diagnosis of Alzheimer’s disease. Pattern Recognit Lett 2010. [DOI: 10.1016/j.patrec.2010.03.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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42
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Classification of functional brain images using a GMM-based multi-variate approach. Neurosci Lett 2010; 474:58-62. [PMID: 20227464 DOI: 10.1016/j.neulet.2010.03.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 03/02/2010] [Accepted: 03/03/2010] [Indexed: 10/19/2022]
Abstract
This paper presents a novel method for automatic selection of regions of interest (ROIs) of functional brain images based on Gaussian mixture models (GMM), which relieves the so-called small size sample problem in the classification of functional brain images for the diagnosis of Alzheimer's disease (AD). In a first step, brain images are preprocessed in order to find an average image including differences between controls and AD patients. Then, ROIs are extracted using a GMM which is adjusted by using the expectation maximization (EM) algorithm. This reduced set of features provides the activation map of each patient and allows us to train statistical classifiers based on support vector machines (SVMs). The leave-one-out cross-validation technique is used to validate the results obtained by the supervised learning-based computer aided diagnosis (CAD) system over databases of SPECT and PET images yielding an accuracy rate up to 96.67%.
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Planar soap bubble clusters with a cavity. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2007; 23:7-11. [PMID: 17520173 DOI: 10.1140/epje/i2006-10082-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2006] [Accepted: 04/19/2007] [Indexed: 05/15/2023]
Abstract
We construct local energy-minimizing bubble clusters in the plane that are not simply-connected. Numerical evidence suggests that these minima are not isolated.
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46
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A theoretical framework for defining some concepts in evolution. RIVISTA DI BIOLOGIA 2006; 99:273-85. [PMID: 17115372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We present a theoretical framework for biological evolution with the intention of giving precise mathematical definitions of some concepts in evolutionary biology such as fitness, evolutionary pressure, specialization and natural selection. In this framework, such concepts are identified with well-known mathematical terms within the theory of dynamical systems. We also discuss some more general implications in evolution; for instance, the fact that our model naturally exhibits a frequency spectrum of the type 1/f for low frequencies of evolutionary events.
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Metabolic indices shift in the hypothalamic-neurohypophysial system during lactation: implications for interpreting their relationship with neuronal activity. Neuroscience 2005; 134:1217-22. [PMID: 16054766 DOI: 10.1016/j.neuroscience.2005.05.059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Revised: 04/11/2005] [Accepted: 05/12/2005] [Indexed: 11/28/2022]
Abstract
Metabolic indices of neuronal activity are thought to predict changes in the frequency of action potentials. There are stimuli that do not shift action potential frequency but change the temporal organization of neuronal firing following modifications of excitatory inputs by inhibitory synaptic activation. To our knowledge it is unknown whether this kind of stimulus associates with adjustments of metabolic markers of neuronal activity. Here, we used the hypothalamic-neurohypophysial system of lactating rats to address whether shifts in the temporal organization of neuronal firing relate with modifications of metabolic markers of neuronal activity. Cytochrome oxidase activity, (3)H-2-deoxyglucose uptake, and the area occupied by blood vessels increased in the paraventricular nucleus and neurohypophysis of lactating rats, as compared with their virgin counterparts. Taken together, these results suggest that metabolic demands denote shifts in the temporal organization of action potentials related with the adjustment of excitatory synaptic activation, and support that changes in metabolic markers do not necessarily reflect shifts in the frequency of action potentials.
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Abstract
OBJECTIVE The San Antonio Lupus Study of Neuropsychiatric Disease is a longitudinal study designed to characterize the spectrum of and important risk factors for specific neuropsychiatric systemic lupus erythematosus (NPSLE) syndromes. METHODS Subjects must meet criteria for SLE and must be at least 18 years of age. A standardized medical history, neurologic, rheumatologic, and psychiatric examinations, computerized neuropsychological evaluation, and serologic testing are performed. RESULTS This report is based on the first 128 subjects (120 women and 8 men) who completed the initial study visit. Data from this initial study visit were evaluated for the prevalence of NPSLE using the American College of Rheumatology case definitions for 19 NPSLE syndromes. One or more NPSLE syndromes were present in 80% of subjects: cerebrovascular disease (2, 2%; ischemic stroke); headaches (73, 57%); mononeuropathy (9, 8%; median 8, ulnar 1); movement disorder (1, 1%; chorea); neuropathy, cranial (2, 2%; trigeminal); polyneuropathy (29, 22%; sensorimotor); seizures (21, 16%; partial); anxiety disorder (27, 24%); major depressive-like episode (37, 28%); mood disorder with depressive features (21, 19%); mood disorder with manic features (3, 3%); mood disorder with mixed features (1, 1%); psychosis (6, 5%). In a subset of 67 patients who received standardized neuropsychological testing, 21% had normal results. In the remainder, the following levels of impairment were seen: 43% mild, 30% moderate, and 6% severe. CONCLUSIONS The prevalence of NPSLE was high in this cohort of unselected patients with SLE. Headaches, cognitive dysfunction, and psychiatric disorders were the most common NPSLE syndromes seen. These results will be easily comparable to other studies also using standardized diagnostic criteria. However, the lack of ethnicity and language-matched normative neuropsychological data may make comparisons of cognitive dysfunction in SLE populations difficult.
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Paraganglioma and adrenal pheochromocytoma presenting simultaneously in an elderly female. Case report and review of the literature. Urol Int 2001; 66:108-9. [PMID: 11223754 DOI: 10.1159/000056581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Paragangliomas are chromaffin tissue tumors arising in an extra-adrenal location. It is quite rare to find a paraganglioma concurrently with a pheochromocytoma. We report a patient who underwent resection of a retroperitoneal mass that was characterized pathologically as a malignant paraganglioma. An incidental finding was a microscopic pheochromocytoma in the ipsilateral adrenal gland.
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