31 results on '"Schulte LM"'
Search Results
2. Change in sagittal balance with placement of an interspinous spacer
- Author
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Matteini Le, Warren D. Yu, O'Brien, and Schulte Lm
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Male ,Lordosis ,Nerve root ,Radiography ,Neurogenic claudication ,Prosthesis Implantation ,Distraction ,medicine ,Humans ,Orthopedics and Sports Medicine ,Prospective Studies ,Radiculopathy ,Postural Balance ,Balance (ability) ,Aged ,Orthodontics ,Aged, 80 and over ,business.industry ,Intermittent Claudication ,Middle Aged ,medicine.disease ,Compression (physics) ,Sagittal plane ,Internal Fixators ,medicine.anatomical_structure ,Treatment Outcome ,Female ,Neurology (clinical) ,Spondylosis ,medicine.symptom ,business - Abstract
Study design A prospective case series. Objective To determine the effect of X-STOP implantation on sagittal spinal balance using 36-inch films. Summary of background data Interspinous process spacers have been shown as an effective treatment of neurogenic claudication. The devices block the last few degrees of extension at the stenotic level, thus preventing compression of the nerve roots. These devices have been criticized because they may push the patient's spine into a kyphotic position. However, opening the stenotic level may allow a patient to stand more upright, thereby improving sagittal balance. Methods Institutional review board's approval was obtained. A prospective study of 20 patients who were undergoing an X-STOP insertion was utilized. Their spines were x-rayed preoperatively and postoperatively with 36-inch films. Preoperative and postoperative sagittal balance was measured with a C7 body plum line on both films and the difference was measured. Lumbar lordosis was also compared using Cobb angles. Results Measurements taken from lateral full-length spine radio-graphs showed an average improvement in sagittal balance of 2.0 cm (range -3.7 to 6.1 cm). The average change in lordosis was -1.1°. Conclusion Although previous studies of interspinous process distraction have examined segmental lordosis, disc angles, and other parameters, this study is the first to examine overall spinal balance on full-length films. Interspinous distraction does not seem to be detrimental to sagittal balance, and may improve it.
- Published
- 2011
3. Change in sagittal balance with placement of an interspinous spacer.
- Author
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Schulte LM, O'brien JR, Matteini LE, Yu WD, Schulte, Leah M, O'Brien, Joseph R, Matteini, Lauren E, and Yu, Warren D
- Abstract
Study Design: A prospective case series.Objective: To determine the effect of X-STOP implantation on sagittal spinal balance using 36-inch films.Summary Of Background Data: Interspinous process spacers have been shown as an effective treatment of neurogenic claudication. The devices block the last few degrees of extension at the stenotic level, thus preventing compression of the nerve roots. These devices have been criticized because they may push the patient's spine into a kyphotic position. However, opening the stenotic level may allow a patient to stand more upright, thereby improving sagittal balance.Methods: Institutional review board's approval was obtained. A prospective study of 20 patients who were undergoing an X-STOP insertion was utilized. Their spines were x-rayed preoperatively and postoperatively with 36-inch films. Preoperative and postoperative sagittal balance was measured with a C7 body plum line on both films and the difference was measured. Lumbar lordosis was also compared using Cobb angles.Results: Measurements taken from lateral full-length spine radio-graphs showed an average improvement in sagittal balance of 2.0 cm (range -3.7 to 6.1 cm). The average change in lordosis was -1.1°.Conclusion: Although previous studies of interspinous process distraction have examined segmental lordosis, disc angles, and other parameters, this study is the first to examine overall spinal balance on full-length films. Interspinous distraction does not seem to be detrimental to sagittal balance, and may improve it. [ABSTRACT FROM AUTHOR]- Published
- 2011
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4. Sexy fingers: Pheromones in the glands of male dendrobatid frogs.
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Almeida DA, Twomey E, Vargas-Salinas F, Meyer C, and Schulte LM
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- Animals, Male, Female, Sexual Behavior, Animal physiology, Pheromones genetics, Sex Attractants genetics, Anura genetics, Transcriptome
- Abstract
Many animals exchange chemicals during courtship and mating. In some amphibians, sexual chemical communication is mediated by pheromones produced in male breeding glands that are transferred to the female's nostrils during mating. This has been mostly studied in salamanders, despite frogs having similar glands and courtship behaviours suggestive of chemical communication. In Neotropical poison frogs (Dendrobatidae and Aromobatidae), males of many species develop breeding glands in their fingers, causing certain fingers to visibly swell. Many also engage in cephalic amplexus, whereby the male's swollen fingers are placed in close contact with the female's nares during courtship. Here, we investigate the possible roles of swollen fingers in pheromone production using whole-transcriptome sequencing (RNAseq). We examined differential gene expression in the swollen versus non-swollen fingers and toes of two dendrobatid species, Leucostethus brachistriatus and Epipedobates anthonyi, both of which have specialised mucous glands in finger IV, the latter of which has cephalic amplexus. The overwhelming pattern of gene expression in both species was strong upregulation of sodefrin precursor-like factors (SPFs) in swollen fingers, a well-known pheromone system in salamanders. The differentially expressed SPF transcripts in each species were very high (>40), suggesting a high abundance of putative protein pheromones in both species. Overall, the high expression of SPFs in the swollen fingers in both species, combined with cephalic amplexus, supports the hypothesis that these traits, widespread across members of the subfamilies Colostethinae and Hyloxalinae (ca. 141 species), are involved in chemical signalling during courtship., (© 2024 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)
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- 2024
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5. Multiple Routes to Color Convergence in a Radiation of Neotropical Poison Frogs.
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Twomey E, Melo-Sampaio P, Schulte LM, Bossuyt F, Brown JL, and Castroviejo-Fisher S
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- Animals, Phylogeny, Pigmentation genetics, Anura, Pterins metabolism, Biological Evolution, Poison Frogs, Poisons
- Abstract
Convergent evolution is defined as the independent evolution of similar phenotypes in different lineages. Its existence underscores the importance of external selection pressures in evolutionary history, revealing how functionally similar adaptations can evolve in response to persistent ecological challenges through a diversity of evolutionary routes. However, many examples of convergence, particularly among closely related species, involve parallel changes in the same genes or developmental pathways, raising the possibility that homology at deeper mechanistic levels is an important facilitator of phenotypic convergence. Using the genus Ranitomeya, a young, color-diverse radiation of Neotropical poison frogs, we set out to 1) provide a phylogenetic framework for this group, 2) leverage this framework to determine if color phenotypes are convergent, and 3) to characterize the underlying coloration mechanisms to test whether color convergence occurred through the same or different physical mechanisms. We generated a phylogeny for Ranitomeya using ultraconserved elements and investigated the physical mechanisms underlying bright coloration, focusing on skin pigments. Using phylogenetic comparative methods, we identified several instances of color convergence, involving several gains and losses of carotenoid and pterin pigments. We also found a compelling example of nonparallel convergence, where, in one lineage, red coloration evolved through the red pterin pigment drosopterin, and in another lineage through red ketocarotenoids. Additionally, in another lineage, "reddish" coloration evolved predominantly through structural color mechanisms. Our study demonstrates that, even within a radiation of closely related species, convergent evolution can occur through both parallel and nonparallel mechanisms, challenging the assumption that similar phenotypes among close relatives evolve through the same mechanisms., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society of Systematic Biologists.)
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- 2023
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6. What Amphibians Can Teach Us About the Evolution of Parental Care.
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Ringler E, Rojas B, Stynoski JL, and Schulte LM
- Abstract
Parenting is considered a key evolutionary innovation that contributed to the diversification and expansion of vertebrates. However, we know little about how such diversity evolved. Amphibians are an ideal group in which to identify the ecological factors that have facilitated or constrained the evolution of different forms of parental care. Among, but also within, the three amphibian orders-Anura, Caudata, and Gymnophiona-there is a high level of variation in habitat use, fertilization mode, mating systems, and parental sex roles. Recent work using broad phylogenetic, experimental, and physiological approaches has helped to uncover the factors that have selected for the evolution of care and transitions between different forms of parenting. Here, we highlight the exceptional diversity of amphibian parental care, emphasize the unique opportunities this group offers for addressing key questions about the evolution of parenting, and give insights into promising novel directions of research., Competing Interests: Disclosure Statement The authors are not aware of any biases that might be perceived as affecting the objectivity of this review.
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- 2023
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7. Better integration of chemical pollution research will further our understanding of biodiversity loss.
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Sylvester F, Weichert FG, Lozano VL, Groh KJ, Bálint M, Baumann L, Bässler C, Brack W, Brandl B, Curtius J, Dierkes P, Döll P, Ebersberger I, Fragkostefanakis S, Helfrich EJN, Hickler T, Johann S, Jourdan J, Klimpel S, Kminek H, Liquin F, Möllendorf D, Mueller T, Oehlmann J, Ottermanns R, Pauls SU, Piepenbring M, Pfefferle J, Schenk GJ, Scheepens JF, Scheringer M, Schiwy S, Schlottmann A, Schneider F, Schulte LM, Schulze-Sylvester M, Stelzer E, Strobl F, Sundermann A, Tockner K, Tröger T, Vilcinskas A, Völker C, Winkelmann R, and Hollert H
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- Biodiversity, Ecosystem
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- 2023
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8. Rifaximin may induce rifampicin resistance in coagulase-negative staphylococci.
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Schulte LM, Nattermann J, Strassburg CP, and Lutz P
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- Humans, Rifaximin therapeutic use, Staphylococcus, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Rifampin pharmacology, Rifampin therapeutic use, Coagulase
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- 2023
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9. Maternal Provisioning of Alkaloid Defenses are Present in Obligate but not Facultative Egg Feeding Dendrobatids.
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Villanueva ED, Brooks OL, Bolton SK, Savastano N, Schulte LM, and Saporito RA
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- Animals, Female, Anura, Larva, Alkaloids, Ants, Poisons
- Abstract
Poison frogs sequester alkaloid defenses from a diet of largely mites and ants. As a result, frogs are defended against certain predators and microbial infections. Frogs in the genus Oophaga exhibit complex maternal care, wherein mothers transport recently hatched tadpoles to nursery pools and return regularly to supply developing tadpoles with unfertilized (nutritive) eggs. Developing tadpoles are obligate egg feeders. Further, female O. pumilio and O. sylvatica maternally provision their nutritive eggs with alkaloid defenses, providing protection to their developing tadpoles at a vulnerable life-stage. In another genus of poison frog, Ranitomeya, tadpoles only receive and consume eggs facultatively, and it is currently unknown if mothers also provision these eggs (and thus their tadpoles) with alkaloid defenses. Here, we provide evidence that mother frogs of another species in the genus Oophaga (Oophaga granulifera) also provision alkaloid defenses to their tadpoles. We also provide evidence that Ranitomeya imitator and R. variabilis eggs and tadpoles do not contain alkaloids, suggesting that mother frogs in this genus do not provision alkaloid defenses to their offspring. Our findings suggest that among dendrobatid poison frogs, maternal provisioning of alkaloids may be restricted to the obligate egg-feeding members of Oophaga., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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10. The effects of olfactory stimulation on the behaviour of captive slender lorises (Loris lydekkerianus).
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Kolden CV and Schulte LM
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- Animals, Grooming, Smell, Social Behavior, Lorisidae physiology
- Abstract
Studies on primate sense of smell are scarce, even though odours represent the main communicative channel for many nocturnal primates such as gray slender lorises (Loris lydekkerianus). Here, we investigate the influence of natural odours on communicative and social behaviours on a group of slender lorises housed at the Frankfurt Zoo. Previously collected chemical marks from unknown conspecifics, urine from a natural predator (rusty-spotted cats) and a control setup were introduced in random order to the group enclosure. We recorded chemical communication behaviours, such as marking and sniffing, social behaviours and general activities. Using generalized linear mixed-effect models, we found that the odours did not have an effect on marking, but on sniffing behaviours of the animals. Conspecific odours decreased the sniffing frequencies of the animals (especially shortly after introduction). When predator odours were introduced, sniffing increased when compared to treatments with conspecific odours, but not in comparison to control treatments. The frequency of social behaviours, feeding and self-grooming did not change in response to predator or conspecific odours. Despite some limitations to our study, the data show a trend that natural odours may trigger some interest in group-kept slender lorises, and further examination of other novel odours may be worth studying (e.g. for potential chemical enrichment in zoos)., (Copyright © 2022 Elsevier B.V. All rights reserved.)
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- 2022
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11. Using iRNA-seq analysis to predict gene expression regulatory level and activity in Zea mays tissues.
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Schulte LM, Koirtyohann KM, and McGinnis KM
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- Gene Expression, Gene Expression Profiling, Gene Expression Regulation, Plant, RNA metabolism, Sequence Analysis, RNA, Transcription Factors genetics, Gene Regulatory Networks, Zea mays
- Abstract
Plants regulate gene expression at the transcriptional and post-transcriptional levels to produce a variety of functionally diverse cells and tissues that ensure normal growth, development, and environmental response. Although distinct gene expression patterns have been characterized between different plant tissues, the specific role of transcriptional regulation of tissue-specific expression is not well-characterized in plants. RNA-seq, while widely used to assay for changes in transcript abundance, does not discriminate between differential expression caused by mRNA degradation and active transcription. Recently, the presence of intron sequences in RNA-seq analysis of libraries constructed with total RNA has been found to coincide with genes undergoing active transcription. We have adapted the intron RNA-sequencing analysis to determine genome-wide transcriptional activity in 2 different maize (Zea mays) tissues: husk and V2-inner stem tissue. A total of 5,341 genes were predicted to be transcriptionally differentially expressed between the 2 tissues, including many genes expected to have biological activity relevant to the functional and developmental identity of each tissue. Correlations with transcriptional enhancer and transcription factor activity support the validity of intron RNA-sequencing predictions of transcriptional regulation. A subset of transcription factors was further analyzed using gene regulatory network analysis to determine the possible impact of their activation. The predicted regulatory patterns between these genes were used to model a potential gene regulatory network of transcription factors and regulatory targets., (© The Author(s) 2022. Published by Oxford University Press on behalf of Genetics Society of America.)
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- 2022
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12. Love bites: male frogs (Plectrohyla, Hylidae) use teeth scratching to deliver sodefrin precursor-like factors to females during amplexus.
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Schulte LM, Martel A, Cruz-Elizalde R, Ramírez-Bautista A, and Bossuyt F
- Abstract
Background: Efficient transfer of chemical signals is important for successful mating in many animal species. Multiple evolutionary lineages of animals evolved direct sex pheromone transmission during traumatic mating-the wounding of the partner with specialized devices-which helps to avoid signal loss to the environment. Although such direct transmission modes of so-called allohormone pheromones are well-documented in invertebrates, they are considered rare in vertebrates. Males of several species of the frog genus Plectrohyla (Hylidae, Anura) have elongated teeth and develop swollen lips during the breeding season. Here we investigated the possibility that these structures are used to scratch the females' skin and apply allohormone pheromones during traumatic mating in several Plectrohyla species., Results: Our behavioural observations revealed that males press their upper jaw onto the females' dorsum during amplexus, leaving small skin scratches with their teeth. Histological examinations of the males' lips identified specialized mucus glands, resembling known amphibian pheromone glands. Whole-transcriptome sequencing of these breeding glands showed high expression of sodefrin precursor-like factor (SPF) proteins, which are known to have a pheromone function in multiple amphibian species., Conclusions: Our study suggests SPF delivery via traumatic mating in several anuran species: the males have specialized breeding glands in the lips for production and secretion and use their elongated teeth as wounding devices for application. We hypothesize that these SPF proteins end up in the females' circulatory system, where understanding their exact function will require further molecular, physiological and behavioural testing., (© 2021. The Author(s).)
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- 2021
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13. Natural variation in social conditions affects male mate choosiness in the amphipod Gammarus roeselii .
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Lipkowski K, Steigerwald S, Schulte LM, Sommer-Trembo C, and Jourdan J
- Abstract
The extent of male mate choosiness is driven by a trade-off between various environmental factors associated with the costs of mate acquisition, quality assessment and opportunity costs. Our knowledge about natural variation in male mate choosiness across different populations of the same species, however, remains limited. In this study, we compared male mate choosiness across 10 natural populations of the freshwater amphipod Gammarus roeselii (Gervais 1835), a species with overall high male mating investments, and evaluated the relative influence of population density and sex ratio (both affecting mate availability) on male mate choosiness. We investigated amplexus establishment after separating mating pairs and presenting focal males with a novel, size-matched female from the same population. Our analysis revealed considerable effects of sex ratio and (to a lesser extent) population density on time until amplexus establishment (choosiness). Male amphipods are able to perceive variable social conditions (e.g., sex ratio) and modify their mating strategy accordingly: We found choosiness to be reduced in increasingly male-biased populations, whereas selectivity increases when sex ratio becomes female biased. With this, our study expands our limited knowledge on natural variations in male mate choosiness and illustrates the importance of sex ratio (i.e., level of competition) for male mating decisions in natural environments. Accounting for variation in sex ratios, therefore, allows envisioning a distinctive variation of choosiness in natural populations and highlights the importance of considering social background information in future behavioral studies., (© The Author(s) (2021). Published by Oxford University Press on behalf of Editorial Office, Current Zoology.)
- Published
- 2021
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14. Developments in Amphibian Parental Care Research: History, Present Advances, and Future Perspectives.
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Schulte LM, Ringler E, Rojas B, and Stynoski JL
- Abstract
Despite rising interest among scientists for over two centuries, parental care behavior has not been as thoroughly studied in amphibians as it has in other taxa. The first reports of amphibian parental care date from the early 18th century, when Maria Sibylla Merian went on a field expedition in Suriname and reported frog metamorphs emerging from their mother's dorsal skin. Reports of this and other parental behaviors in amphibians remained descriptive for decades, often as side notes during expeditions with another purpose. However, since the 1980s, experimental approaches have proliferated, providing detailed knowledge about the adaptive value of observed behaviors. Today, we recognize more than 30 types of parental care in amphibians, but most studies focus on just a few families and have favored anurans over urodeles and caecilians. Here, we provide a synthesis of the last three centuries of parental care research in the three orders comprising the amphibians. We draw attention to the progress from the very first descriptions to the most recent experimental studies, and highlight the importance of natural history observations as a source of new hypotheses and necessary context to interpret experimental findings. We encourage amphibian parental care researchers to diversify their study systems to allow for a more comprehensive perspective of the behaviors that amphibians exhibit. Finally, we uncover knowledge gaps and suggest new avenues of research using a variety of disciplines and approaches that will allow us to better understand the function and evolution of parental care behaviors in this diverse group of animals.
- Published
- 2020
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15. Multiple Independent Recruitment of Sodefrin Precursor-Like Factors in Anuran Sexually Dimorphic Glands.
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Bossuyt F, Schulte LM, Maex M, Janssenswillen S, Novikova PY, Biju SD, Van de Peer Y, Matthijs S, Roelants K, Martel A, and Van Bocxlaer I
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- Animals, Anura genetics, Exocrine Glands metabolism, Female, Male, Oligopeptides metabolism, Phylogeny, Sex Characteristics, Exome Sequencing, Anura metabolism, Sex Attractants metabolism
- Abstract
Chemical signaling in animals often plays a central role in eliciting a variety of responses during reproductive interactions between males and females. One of the best-known vertebrate courtship pheromone systems is sodefrin precursor-like factors (SPFs), a family of two-domain three-finger proteins with a female-receptivity enhancing function, currently only known from salamanders. The oldest divergence between active components in a single salamander species dates back to the Late Paleozoic, indicating that these proteins potentially gained a pheromone function earlier in amphibian evolution. Here, we combined whole transcriptome sequencing, proteomics, histology, and molecular phylogenetics in a comparative approach to investigate SPF occurrence in male breeding glands across the evolutionary tree of anurans (frogs and toads). Our study shows that multiple families of both terrestrially and aquatically reproducing frogs have substantially increased expression levels of SPFs in male breeding glands. This suggests that multiple anuran lineages make use of SPFs to complement acoustic and visual sexual signaling during courtship. Comparative analyses show that anurans independently recruited these proteins each time the gland location on the male's body allowed efficient transmission of the secretion to the female's nares., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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16. Management of Lower Extremity Long-bone Fractures in Spinal Cord Injury Patients.
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Schulte LM, Scully RD, and Kappa JE
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- Bones of Lower Extremity, Fracture Fixation, Internal methods, Fractures, Bone diagnostic imaging, Humans, Fractures, Bone surgery, Leg Bones injuries, Spinal Cord Injuries complications
- Abstract
The AO classification system, used as a guide for modern fracture care and fixation, follows a basic philosophy of care that emphasizes early mobility and return to function. Lower extremity long-bone fractures in patients with spinal cord injury often are pathologic injuries that present unique challenges, to which the AO principles may not be entirely applicable. Optimal treatment achieves healing without affecting the functional level of the patient. These injuries often result from low-energy mechanisms in nonambulatory patients with osteopenic bone and a thin, insensate soft-tissue envelope. The complication rate can be high, and the outcomes can be catastrophic without proper care. Satisfactory results can be obtained through various methods of immobilization. Less frequently, internal fixation is applied. In certain cases, after discussion with the patient, amputation may be suitable. Prevention strategies aim to minimize bone loss and muscle atrophy.
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- 2017
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17. Searching for hormonal facilitators: Are vasotocin and mesotocin involved in parental care behaviors in poison frogs?
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Schulte LM and Summers K
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- Animals, Female, Linear Models, Male, Oxytocin pharmacology, Statistics, Nonparametric, Anura physiology, Maternal Behavior drug effects, Oxytocics pharmacology, Oxytocin analogs & derivatives, Paternal Behavior drug effects, Vasotocin pharmacology
- Abstract
Although the involvement of peptide hormones in parental care behaviors is well investigated in vertebrates, in amphibians the physiological basis of parental care is largely unknown. This is all the more surprising as parental care behaviors in these tetrapods are remarkably diverse. The poison frog Ranitomeya imitator performs biparental care, including clutch guarding, tadpole transportation and nutrient provisioning. Here we tested whether the nonapeptides arginine-vasotocin (AVT) and mesotocin (MT) are involved in clutch guarding and tadpole transportation in these frogs. In ex-sito experiments we injected males and females after clutch deposition and before tadpole transport with AVT and MT, respectively, as well as their antagonist or a control. We measured two types of egg caring behavior (intense and general care) and compared the success rate of tadpole transportation after treatments. Surprisingly we found that AVT did not trigger, but decreased intense egg care behaviors in males and females. However, there was a trend for general care behavior to increase, which might explain the adverse effect regarding intense care. MT did not have an effect on egg caring behaviors, but after administration of this hormone males were less likely to transport their offspring later on. Our results indicate that AVT might be partly involved in egg caring behaviors in R. imitator, while MT does not appear to play any role in behaviors prior to tadpole transportation in males. This implies that other hormones, such as steroids or prolactin are likely to be important for early parental care behaviors in poison frogs., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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18. Enhancement of fracture healing in the rat, modulated by compounds that stimulate inducible nitric oxide synthase: Acceleration of fracture healing via inducible nitric oxide synthase.
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Rajfer RA, Kilic A, Neviaser AS, Schulte LM, Hlaing SM, Landeros J, Ferrini MG, Ebramzadeh E, and Park SH
- Abstract
Objectives: We investigated the effects on fracture healing of two up-regulators of inducible nitric oxide synthase (iNOS) in a rat model of an open femoral osteotomy: tadalafil, a phosphodiesterase inhibitor, and the recently reported nutraceutical, COMB-4 (consisting of L-citrulline, Paullinia cupana, ginger and muira puama), given orally for either 14 or 42 days., Materials and Methods: Unilateral femoral osteotomies were created in 58 male rats and fixed with an intramedullary compression nail. Rats were treated daily either with vehicle, tadalafil or COMB-4. Biomechanical testing of the healed fracture was performed on day 42. The volume, mineral content and bone density of the callus were measured by quantitative CT on days 14 and 42. Expression of iNOS was measured by immunohistochemistry., Results: When compared with the control group, the COMB-4 group exhibited 46% higher maximum strength ( t -test, p = 0.029) and 92% higher stiffness ( t -test, p = 0.023), but no significant changes were observed in the tadalafil group. At days 14 and 42, there was no significant difference between the three groups with respect to callus volume, mineral content and bone density. Expression of iNOS at day 14 was significantly higher in the COMB-4 group which, as expected, had returned to baseline levels at day 42., Conclusion: This study demonstrates an enhancement in fracture healing by an oral natural product known to augment iNOS expression. Cite this article: R. A. Rajfer, A. Kilic, A. S. Neviaser, L. M. Schulte, S. M. Hlaing, J. Landeros, M. G. Ferrini, E. Ebramzadeh, S-H. Park. Enhancement of fracture healing in the rat, modulated by compounds that stimulate inducible nitric oxide synthase: Acceleration of fracture healing via inducible nitric oxide synthase. Bone Joint Res 2017:6:-97. DOI: 10.1302/2046-3758.62.BJR-2016-0164.R2., (© 2017 Park et al.)
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- 2017
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19. Poison frogs.
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Stynoski JL, Schulte LM, and Rojas B
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- Animals, Anura metabolism, Female, Male, Skin metabolism, Skin Pigmentation, Toxins, Biological metabolism, Anura physiology, Poisons metabolism
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Stynoski et al. introduce the dendrobatids, a charismatic group of frogs known for their colourful and often poisonous skin., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2015
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20. Decoding and Discrimination of Chemical Cues and Signals: Avoidance of Predation and Competition during Parental Care Behavior in Sympatric Poison Frogs.
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Schulte LM, Krauss M, Lötters S, Schulze T, and Brack W
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- Animals, Anura genetics, Nesting Behavior, Smell, Sympatry, Animal Communication, Anura physiology, Cues, Olfactory Perception, Pheromones, Predatory Behavior
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The evolution of chemical communication and the discrimination between evolved functions (signals) and unintentional releases (cues) are among the most challenging issues in chemical ecology. The accurate classification of inter- or intraspecific chemical communication is often puzzling. Here we report on two different communication systems triggering the same parental care behavior in the poison frog Ranitomeya variabilis. This species deposits its tadpoles and egg clutches in phytotelmata and chemically recognizes and avoids sites with both predatory conspecific and non-predatory heterospecific tadpoles (of the species Hyloxalus azureiventris). Combining chemical analyses with in-situ bioassays, we identified the molecular formulas of the chemical compounds triggering this behavior. We found that both species produce distinct chemical compound combinations, suggesting two separate communication systems. Bringing these results into an ecological context, we classify the conspecific R. variabilis compounds as chemical cues, advantageous only to the receivers (the adult frogs), not the emitters (the tadpoles). The heterospecific compounds, however, are suggested to be chemical signals (or cues evolving into signals), being advantageous to the emitters (the heterospecific tadpoles) and likely also to the receivers (the adult frogs). Due to these assumed receiver benefits, the heterospecific compounds are possibly synomones which are advantageous to both emitter and receiver ‒ a very rare communication system between animal species, especially vertebrates.
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- 2015
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21. Management of adult diaphyseal both-bone forearm fractures.
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Schulte LM, Meals CG, and Neviaser RJ
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- Adult, Diaphyses diagnostic imaging, Diaphyses injuries, Humans, Orthopedic Fixation Devices, Postoperative Complications, Radiography, Radius Fractures diagnostic imaging, Ulna Fractures diagnostic imaging, Diaphyses surgery, Fracture Fixation, Internal, Radius Fractures surgery, Ulna Fractures surgery
- Abstract
Simultaneous diaphyseal fractures of the radius and ulna, often referred to as both-bone forearm fractures, are frequently encountered by orthopaedic surgeons. Adults with this injury are typically treated with open reduction and internal fixation because of the propensity for malunion of the radius and ulna and the resulting loss of forearm rotation. Large case series support the use of plate and screw fixation for simple fractures. More complex fractures are managed according to strain theory, with the intention of controlling rather than eliminating motion at the fracture site. This can be achieved with flexible plate and screw constructs or intramedullary nails. In general, results of surgical fixation have been good, with only modest losses of forearm strength and rotation. Notable complications include nonunion, malunion, and refracture after device removal., (Copyright 2014 by the American Academy of Orthopaedic Surgeons.)
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- 2014
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22. A danger foreseen is a danger avoided: how chemical cues of different tadpoles influence parental decisions of a Neotropical poison frog.
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Schulte LM and Lötters S
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- Animals, Cues, Ecosystem, Female, Food Chain, Humans, Larva physiology, Male, Bufonidae physiology, Ranidae physiology, Reproduction physiology
- Abstract
The protection of offspring against predators and competitors is especially important in organisms using spatially separated breeding resources, impeding the offspring's chances to escape. One example of such isolated reproductive resources are phytotelmata (small water bodies in plant axils), exploited by the Neotropical poison frog Ranitomeya variabilis (Dendrobatidae) for both clutch and tadpole deposition. Because poison frog tadpoles are often cannibalistic, parents tend to avoid deposition with conspecifics. Previous studies have shown that this avoidance is based on chemical cues produced by conspecific tadpoles. Further, cues produced by phylogenetically less-related tadpoles (Bufonidae) were avoided for clutch but not tadpole depositions. We analyzed how the different responses to tadpole cues are triggered. We tested the reactions of parental R. variabilis to tadpole cues of species differing in two aspects: whether or not they are dendrobatids, and whether or not they reproduce in phytotelmata. We found that for clutch deposition, tadpole cues were always avoided, i.e., all tadpoles were treated by the frogs as if they pose a danger to the eggs. However, responses varied for tadpole depositions: while dendrobatid larvae living in phytotelmata were avoided, those breeding in streams were not. Non-poison frog tadpoles were ignored when associated with habitat other than phytotelmata, but they were preferred when living in phytotelmata. This suggests that both phylogeny and tadpole habitat are important triggers for the decisions made by R. variabilis. Only tadpoles using the same breeding resources are considered as relevant for the frog's own larvae (i.e., as a potential danger or food resource), while further decisions are related to evolutionary relationship.
- Published
- 2014
- Full Text
- View/download PDF
23. Scapula fractures: interobserver reliability of classification and treatment.
- Author
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Neuhaus V, Bot AG, Guitton TG, Ring DC, Abdel-Ghany MI, Abrams J, Abzug JM, Adolfsson LE, Balfour GW, Bamberger HB, Barquet A, Baskies M, Batson WA, Baxamusa T, Bayne GJ, Begue T, Behrman M, Beingessner D, Biert J, Bishop J, Alves MB, Boyer M, Brilej D, Brink PR, Brunton LM, Buckley R, Cagnone JC, Calfee RP, Campinhos LA, Cassidy C, Catalano L 3rd, Chivers K, Choudhari P, Cimerman M, Conflitti JM, Costanzo RM, Crist BD, Cross BJ, Dantuluri P, Darowish M, de Bedout R, DeCoster T, Dennison DG, DeNoble PH, DeSilva G, Dienstknecht T, Duncan SF, Duralde XA, Durchholz H, Egol K, Ekholm C, Elias N, Erickson JM, Esparza JD, Fernandes CH, Fischer TJ, Fischmeister M, Forigua Jaime E, Getz CL, Gilbert RS, Giordano V, Glaser DL, Gosens T, Grafe MW, Filho JE, Gray RR, Gulotta LV, Gummerson NW, Hammerberg EM, Harvey E, Haverlag R, Henry PD, Hobby JL, Hofmeister EP, Hughes T, Itamura J, Jebson P, Jenkinson R, Jeray K, Jones CM, Jones J, Jubel A, Kaar SG, Kabir K, Kaplan FT, Kennedy SA, Kessler MW, Kimball HL, Kloen P, Klostermann C, Kohut G, Kraan GA, Kristan A, Loebenberg MI, Malone KJ, Marsh L, Martineau PA, McAuliffe J, McGraw I, Mehta S, Merchant M, Metzger C, Meylaerts SA, Miller AN, Wolf JM, Murachovsky J, Murthi A, Nancollas M, Nolan BM, Omara T, Omid R, Ortiz JA, Overbeck JP, Castillo AP, Pesantez R, Polatsch D, Porcellini G, Prayson M, Quell M, Ragsdell MM, Reid JG, Reuver JM, Richard MJ, Richardson M, Rizzo M, Rowinski S, Rubio J, Guerrero CG, Satora W, Schandelmaier P, Scheer JH, Schmidt A, Schubkegel TA, Schulte LM, Schumer ED, Sears BW, Shafritz AB, Shortt NL, Siff T, Silva DM, Smith RM, Spruijt S, Stein JA, Pemovska ES, Streubel PN, Swigart C, Swiontkowski M, Thomas G, Tolo ET, Turina M, Tyllianakis M, van den Bekerom MP, van der Heide H, van de Sande MA, van Eerten PV, Verbeek DO, Hoffmann DV, Vochteloo AJ, Wagenmakers R, Wall CJ, Wallensten R, Wascher DC, Weiss L, Wiater JM, Wills BP, Wint J, Wright T, Young JP, Zalavras C, Zura RD, and Zyto K
- Subjects
- Female, Fractures, Bone diagnostic imaging, Fractures, Bone surgery, Humans, Imaging, Three-Dimensional, Male, Observer Variation, Reproducibility of Results, Scapula diagnostic imaging, Tomography, X-Ray Computed, Fractures, Bone classification, Fractures, Bone therapy, Scapula injuries
- Abstract
Objectives: There is substantial variation in the classification and management of scapula fractures. The first purpose of this study was to analyze the interobserver reliability of the OTA/AO classification and the New International Classification for Scapula Fractures. The second purpose was to assess the proportion of agreement among orthopaedic surgeons on operative or nonoperative treatment., Design: Web-based reliability study., Setting: Independent orthopaedic surgeons from several countries were invited to classify scapular fractures in an online survey., Participants: One hundred three orthopaedic surgeons evaluated 35 movies of three-dimensional computerized tomography reconstruction of selected scapular fractures, representing a full spectrum of fracture patterns., Main Outcome Measurements: Fleiss kappa (κ) was used to assess the reliability of agreement between the surgeons., Results: The overall agreement on the OTA/AO classification was moderate for the types (A, B, and C, κ = 0.54) with a 71% proportion of rater agreement (PA) and for the 9 groups (A1 to C3, κ = 0.47) with a 57% PA. For the New International Classification, the agreement about the intraarticular extension of the fracture (Fossa (F), κ = 0.79) was substantial and the agreement about a fractured body (Body (B), κ = 0.57) or process was moderate (Process (P), κ = 0.53); however, PAs were more than 81%. The agreement on the treatment recommendation was moderate (κ = 0.57) with a 73% PA., Conclusions: The New International Classification was more reliable. Body and process fractures generated more disagreement than intraarticular fractures and need further clear definitions.
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- 2014
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24. Do poison frogs recognize chemical cues of the other sex or do they react to cues of stressed conspecifics?
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Schulte LM and Rössler DC
- Subjects
- Animals, Female, Male, Recognition, Psychology physiology, Smell physiology, Animal Communication, Cues, Ranidae physiology, Sex Attractants physiology, Sexual Behavior, Animal physiology
- Abstract
Although anuran communication primarily takes place acoustically, chemical cues are also often used for intra- and intersexual communication in frogs. In the present study we analyzed the behavior of the poison frog Ranitomeya variabilis when presented chemical cues of same-sex or opposite-sex conspecifics. Chemical cues were obtained by keeping a single frog on a moist paper towel for about 47h. Afterwards two paper towels were offered to a test animal, one containing the chemical cues, the other containing rainwater only. We ran trials presenting female cues to males, males cues to males as well as male cues to females. The results of the trials were not significant in terms of intersexual communication. The overall response revealed a clear avoidance strategy which leads us to the assumption that disturbance cues unintentionally occurred during the experiment. The rather small size of the containers used to obtain chemical cues prior to the trials probably lead to confinement stress which consequently caused increased urination containing stress hormones that were detected by the test animals. This is the first proof of disturbance cues and their effects in adult anurans. The results of this study do not allow conclusions about inter- or intrasexual chemical communication of R. variabilis, but they allow implications and revisions for future experiments on this topic., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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25. Deep vein thrombosis and pulmonary embolism after spine surgery: incidence and patient risk factors.
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Schulte LM, O'Brien JR, Bean MC, Pierce TP, Yu WD, and Meals C
- Subjects
- Anticoagulants therapeutic use, Humans, Incidence, Kyphoplasty, Multivariate Analysis, Pulmonary Embolism prevention & control, Retrospective Studies, Risk Factors, Spine surgery, Venous Thrombosis prevention & control, Arthroplasty, Postoperative Complications epidemiology, Pulmonary Embolism epidemiology, Spinal Fusion methods, Venous Thrombosis epidemiology
- Abstract
Anticoagulation after spine surgery confers the unique risk of epidural hematoma. We sought to determine the incidence of and patient risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE) after spine surgery. We retrospectively reviewed the charts of 1485 patients who had spine surgery at a single tertiary-care center between 2002 and 2009. DVT and PE incidence were recorded along with pertinent patient history information. Univariate and multivariate analyses were performed on the data. VTE incidence was 1.1% (DVTs, 0.7%; PEs, 0.4%). Univariate analysis demonstrated that VTEs had 9 positive risk factors: active malignancy, prior DVT or PE, estrogen replacement therapy, discharge to a rehabilitation facility, hypertension, major depressive disorder, renal disease, congestive heart failure, and benign prostatic hyperplasia (P<.05). Multivariate analysis demonstrated 4 independent risk factors: prior DVT or PE, estrogen replacement therapy, discharge to a rehabilitation facility, and major depressive disorder (P>.05). Surgeons with an improved understanding of VTE after spine surgery can balance the risks and benefits of postoperative anticoagulation.
- Published
- 2013
26. Proximal periarticular locking plates in proximal humeral fractures: functional outcomes.
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Schulte LM, Matteini LE, and Neviaser RJ
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Follow-Up Studies, Fracture Healing, Humans, Male, Middle Aged, Prosthesis Design, Radiography, Retrospective Studies, Shoulder Fractures diagnostic imaging, Shoulder Fractures physiopathology, Shoulder Injuries, Shoulder Joint physiopathology, Treatment Outcome, Young Adult, Bone Plates, Bone Screws, Fracture Fixation, Internal instrumentation, Range of Motion, Articular, Shoulder Fractures surgery, Shoulder Joint surgery
- Abstract
Background: Some recent studies have asserted that locking plates do not provide adequate fixation of proximal humeral fractures. The purpose of this study is to review our experience with proximal humeral locking plates, including complications, functional outcomes, and predictors of successful treatment., Materials and Methods: At our institution, 45 patients (46 shoulders) with displaced proximal humeral fractures were treated with a proximal humeral locking plate over a 6-year period. Patients underwent standard surgical and rehabilitation protocols and were evaluated clinically with Disabilities of the Arm, Shoulder and Hand and American Shoulder and Elbow Surgeons standardized outcome measurements and range of motion at last follow-up. Radiographs obtained preoperatively, immediately postoperatively, and at final follow-up were evaluated for fracture type, union, and change in alignment., Results: There were 43 patients (44 shoulders) available for range-of-motion and functional outcome measures with an average follow-up of 34 months. Fracture types included 19 two-part, 21 three-part, 3 four-part, and 1 head-splitting fracture. The mean Disabilities of the Arm, Shoulder and Hand score was 11. The average American Shoulder and Elbow Surgeons score was 85. The average visual analog pain score was 0.8. The average range of motion was as follows: elevation, 140°; external rotation at side, 49°; external rotation in abduction, 77°; and internal rotation, T11. No patient had evidence of screw cutout, varus collapse, or avascular necrosis. One patient required hardware removal., Conclusions: Displaced proximal humeral fractures can be successfully fixed with locking plates when attention is paid to anatomic reduction, proper plate placement below to the greater tuberosity to allow abduction, screws in the head with subchondral bone purchase, calcar screws from inferior-lateral to superior-medial and delaying shoulder motion until at least 2 weeks., (Copyright © 2011 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)
- Published
- 2011
- Full Text
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27. Risk stratification by the "EPA+DHA level" and the "EPA/AA ratio" focus on anti-inflammatory and antiarrhythmogenic effects of long-chain omega-3 fatty acids.
- Author
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Rupp H, Wagner D, Rupp T, Schulte LM, and Maisch B
- Subjects
- Administration, Oral, Anti-Inflammatory Agents administration & dosage, Arrhythmias, Cardiac blood, Arrhythmias, Cardiac mortality, Coronary Artery Disease blood, Coronary Artery Disease mortality, Diet, Docosahexaenoic Acids blood, Dose-Response Relationship, Drug, Eicosapentaenoic Acid blood, Humans, Nutrition Policy, Risk Factors, Treatment Outcome, Arrhythmias, Cardiac prevention & control, Coronary Artery Disease prevention & control, Dietary Supplements, Docosahexaenoic Acids administration & dosage, Eicosanoic Acids blood, Eicosapentaenoic Acid administration & dosage, Fatty Acids, Omega-3 administration & dosage, Risk Assessment methods
- Abstract
The identification of risks associated with sudden cardiac death requires further investigations. The question was addressed whether parameters can be established which not only describe an increased risk for an enhanced electrical instability of the heart but also of inflammatory events underlying plaque rupture. Emphasis is placed on dose-dependent effects of the long-chain omega-(omega-)3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Since free acids of EPA and DHA are required for most of their biological effects, it appears essential not only to build up stores in the body for release of these fatty acids, but also to provide a sustained uptake of EPA and DHA in the form of ethyl esters. In contrast to rapidly absorbed triacylglycerols from fish, ethyl esters are taken up more slowly within 24 h. For the administration of 1 g/day highly purified EPA+DHA ethyl esters (Omacor) to healthy volunteers, it is shown that EPA is increased from 0.6% to 1.4% within 10 days, while DHA is increased from 2.9% to 4.3%. After withdrawal, EPA and DHA approach baseline values within 10 days. A gas chromatographic procedure was established which requires only 10 microl of whole blood for the identification of more than 35 fatty acids. Evidence is summarized strengthening the concept that a low "EPA+DHA level" presents a risk for sudden cardiac death and that the administration of 840 mg/day of EPA+DHA ethyl esters raises the "EPA+DHA level" to approximately 6% that is associated with a marked protection from sudden cardiac death. For reducing pro-inflammatory eicosanoids and cytokines, a higher "EPA+DHA level" is required which can be achieved with an intake of 2-4 g/day of 84% EPA+DHA ethyl esters. For assessing influences from pro-inflammatory eicosanoids and cytokines, the EPA/arachidonic acid ratio ("EPA/AA ratio") was identified as diagnostic parameter. To assess the dietary EPA+DHA intake, fatty acids were determined in fish dishes of the cafeteria of the Philipps University Hospital Marburg, Germany. The EPA+DHA content of the popular Alaska Pollock was 125 +/- 70 mg/100 g. A once daily fish dish can thus not provide the 840 mg/day EPA+DHA administered in the GISSI Prevention Study in the form of ethyl ester which markedly reduced the risk of sudden cardiac death in postmyocardial infarction patients. Nonetheless, at least two preferably oily fish meals per week should be consumed as preventive measure by persons without coronary artery disease. With documented coronary heart disease, it was advised to consume approximately 1 g/day of EPA+DHA.
- Published
- 2004
- Full Text
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28. Use of diagnosis codes to understand variations in hysterectomy rates: a pilot study.
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Reid BA, Aisbett CW, Jones LM, Palmer GR, Mira M, Muhlen-Schulte LM, Reti L, and Roberts RF
- Subjects
- Australia, Female, Genital Diseases, Female surgery, Humans, Pilot Projects, Poisson Distribution, Genital Diseases, Female diagnosis, Hysterectomy statistics & numerical data
- Published
- 2000
- Full Text
- View/download PDF
29. Regulation of sarcoplasmic reticulum calcium pump gene expression by hindlimb unweighting.
- Author
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Schulte LM, Navarro J, and Kandarian SC
- Subjects
- Animals, Calcium-Transporting ATPases isolation & purification, Calcium-Transporting ATPases metabolism, Female, Hindlimb, Muscle Contraction, Muscle Denervation, Muscle Relaxation, Muscles enzymology, Muscles innervation, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Rats, Wistar, Receptors, Cholinergic genetics, Stress, Mechanical, Time Factors, Calcium-Transporting ATPases genetics, Gene Expression Regulation, Enzymologic, Muscles physiology, Sarcoplasmic Reticulum physiology
- Abstract
Hindlimb unweighting (HU) causes upregulation of several muscle-specific genes responsible for the slow-to-fast transition in soleus skeletal muscle properties despite the profound muscle atrophy. The purpose of this study was to examine the expression of the fast and slow isoforms of the sarcoplasmic reticulum Ca(2+)-ATPase at the mRNA and protein level in the soleus muscle over a time course of HU and relate them to Ca(2+)-dependent ATPase activity and selected contractile properties. mRNA levels of the acetylcholine receptor (AChR) were measured to compare the signal of unweighting with denervation. Atrophy of the soleus muscles from tail-suspended rats was observed at all time points with muscle mass decreased by 52% at 28 days of HU (P < 0.05). Northern blot analysis showed the relative expression of the fast Ca2+ pump mRNA increased by 0, 250, 910, 1,340, and 4,050% over control levels at 1, 4, 7, 14, and 28 days of HU, respectively, whereas changes in slow mRNA were variable and modest in comparison. For the same time points, Western blot analysis showed relative expression of the fast Ca2+ pump protein increased by 30, 110, 320, 280, and 300% over control levels, whereas the slow-pump protein expression was unchanged except for a 75% decrease at 28 days of HU. Specific Ca(2+)-dependent ATPase activity was increased (P < 0.05) by 170% at 28 days of HU. Contractile properties measured in vitro at 14 and 28 days revealed time to peak tension and one-half relaxation time were shortened (P < 0.05) and a rightward shift in the tension-frequency curves in unloaded soleus muscles.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
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30. Age effects on myosin subunit and biochemical alterations with skeletal muscle hypertrophy.
- Author
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Kandarian SC, Schulte LM, and Esser KA
- Subjects
- Aging pathology, Animals, Female, Hypertrophy, Muscles pathology, Myofibrils metabolism, Rats, Rats, Inbred Strains, Aging metabolism, Muscles metabolism, Myosins metabolism
- Abstract
The purpose of this study was to determine whether skeletal muscle mass, myofibrillar adenosinetriphosphatase activity, and the expression of myosin heavy (MHC) and light chain subunits are differentially affected in juvenile (4 wk) and young adult (12 wk) rats by a hypertrophic growth stimulus. Hypertrophy of the plantaris or soleus was studied 4 wk after ablation of either two [gastrocnemius (GTN) and soleus or plantaris] or one (GTN) synergistic muscle(s). There was no difference in the relative magnitude of hypertrophy because of age. Plantaris myofibrillar adenosinetriphosphatase activity was decreased 21 and 12% in juvenile and adult rats, respectively, as a result of ablation of both the GTN and soleus. Slow myosin light chain isoforms (1s and 2s) were expressed to a greater extent in hypertrophied plantaris muscles of both ages, but the increase in 1s was greater in juvenile rats. The relative expression of slow beta-MHC in hypertrophied plantaris muscles increased by 470 and 350%, whereas MHC IIb decreased by 70 and 33% in juvenile and adult rats, respectively. The relative expression of MHC IIa increased (56%) in the plantaris after ablation in juvenile rats only. These shifts in myosin subunit expression and the increases in mass were generally about one-half the magnitude when only the GTN was removed. There were no detectable myosin shifts in hypertrophied soleus muscles. Although the extent of muscle hypertrophy is similar, the shifts in myosin subunits were greater in juvenile than in young adult rats.
- Published
- 1992
- Full Text
- View/download PDF
31. Elevated interstitial fluid volume in rat soleus muscles by hindlimb unweighting.
- Author
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Kandarian SC, Boushel RC, and Schulte LM
- Subjects
- Animals, Body Weight physiology, Female, Muscle Contraction physiology, Muscles pathology, Muscular Atrophy pathology, Organ Size physiology, Rats, Rats, Inbred Strains, Extracellular Space physiology, Hindlimb physiology, Muscles physiology
- Abstract
Hindlimb unweighting is a commonly used model to study skeletal muscle atrophy associated with disuse and exposure to microgravity. However, a discrepancy in findings between single fibers and whole muscle has been observed. In unweighted solei, specific tension deficits are greater in whole muscle than in single fibers. Also, metabolic enzyme activity when normalized per gram of mass is depressed in whole muscle but not in single fibers. These observations suggest that soleus muscle interstitial fluid volume may be elevated with atrophy caused by unweighting in rats. The purpose of this study was to determine if soleus muscle atrophy induced by unweighting is accompanied by alterations in muscle interstitial fluid volume and to calculate the effect of any such alterations on the muscle specific tension (N/cm2 muscle cross-sectional area). Nine female Wistar rats (200 g) were hindlimb unweighted (HU) by tail suspension. Soleus muscles were studied after 28 days and compared with those from five age-matched control (C) rats. Interstitial fluid volume ([3H]inulin space) and maximum tetanic tension (Po) were measured in vitro at 25 degrees C. Soleus muscles atrophied 58% because of unweighting (C = 147.8 +/- 2.3 mg; HU = 62.3 +/- 3.6 mg, P less than 0.001). Relative muscle interstitial fluid volume increased 107% in HU rats (35.5 +/- 2.8 microliters/100 mg wet mass) compared with the control value of 17.2 +/- 0.5 microliters/100 mg (P less than 0.001); however, absolute interstitial fluid volume (microliters) was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
- Full Text
- View/download PDF
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