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A fantastic new species of secretive forest frog discovered from forest fragments near Andasibe, Madagascar. ZOOSYST EVOL 2021. [DOI: 10.3897/zse.97.73630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We describe a fantastic new species of forest frog (Mantellidae: Gephyromantis: subgenus: Laurentomantis) from moderately high elevations in the vicinity of Andasibe, Madagascar. This region has been surveyed extensively and has a remarkably high anuran diversity with many undocumented species still being discovered. Surprisingly, by exploring areas around Andasibe that lacked biodiversity surveys, we discovered a spectacular and clearly morphologically distinct species, previously unknown to science, Gephyromantis marokorokosp. nov., documented for the first time in 2015. The new species is well characterised by a very rugose and granular dorsum, dark brown skin with bright red mottling, sparse light orange to white spots on the ventre, vibrant red eyes and femoral glands present only in males that consist of eight medium-sized granules. Bioacoustically, the new species has a quiet advertisement call that differs from related species by having a moderate call duration, 2–4 strongly pulsed notes and a slow note repetition rate. Furthermore, it has substantial differentiation in mitochondrial DNA, with pairwise distances of 7–9% to all other related species in sequences of the mitochondrial 16S rRNA marker. Additional evidence is given through a combined four mitochondrial markers and four nuclear exons concatenated species tree, strongly supporting G. striatus as the sister species of the new species in both analyses. The discovery of this new species highlights the need for continued inventory work in high elevation rainforests of Madagascar, even in relatively well-studied regions.
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Climate change, extinction, and Sky Island biogeography in a montane lizard. Mol Ecol 2019; 28:2610-2624. [PMID: 30843297 DOI: 10.1111/mec.15073] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 02/16/2019] [Accepted: 02/26/2019] [Indexed: 12/24/2022]
Abstract
Around the world, many species are confined to "Sky Islands," with different populations in isolated patches of montane habitat. How does this pattern arise? One scenario is that montane species were widespread in lowlands when climates were cooler, and were isolated by local extinction caused by warming conditions. This scenario implies that many montane species may be highly susceptible to anthropogenic warming. Here, we test this scenario in a montane lizard (Sceloporus jarrovii) from the Madrean Sky Islands of southeastern Arizona. We combined data from field surveys, climate, population genomics, and physiology. Overall, our results support the hypothesis that this species' current distribution is explained by local extinction caused by past climate change. However, our results for this species differ from simple expectations in several ways: (a) their absence at lower elevations is related to warm winter temperatures, not hot summer temperatures; (b) they appear to exclude a low-elevation congener from higher elevations, not the converse; (c) they are apparently absent from many climatically suitable but low mountain ranges, seemingly "pushed off the top" by climates even warmer than those today; (d) despite the potential for dispersal among ranges during recent glacial periods (~18,000 years ago), populations in different ranges diverged ~4.5-0.5 million years ago and remained largely distinct; and (e) body temperatures are inversely related to climatic temperatures among sites. These results may have implications for many other Sky Island systems. More broadly, we suggest that Sky Island species may be relevant for predicting responses to future warming.
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Inferring introgression using RADseq and
D
FOIL
: Power and pitfalls revealed in a case study of spiny lizards (
Sceloporus
). Mol Ecol Resour 2019; 19:818-837. [DOI: 10.1111/1755-0998.12972] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 10/26/2018] [Indexed: 02/03/2023]
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The smallest ‘true chameleon’ from Madagascar: a new, distinctly colored species of the Calumma boettgeri complex (Squamata, Chamaeleonidae). ZOOSYST EVOL 2018. [DOI: 10.3897/zse.94.27305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
On a recent expedition to eastern Madagascar, we discovered a distinct new species of the genusCalummathat we describe here using an integrative approach combining morphology, coloration, osteology and molecular genetics.Calummaroalokosp. n.has a dermal rostral appendage and occipital lobes, and belongs to theC.boettgericomplex, within the Madagascar-endemic pheneticC.nasutumspecies group. It is readily distinguished from other species of theC.boettgericomplex by a characteristic two-toned body coloration and small body size with a snout-vent length of 45.6 mm in an adult male. The osteology of the skull, with a prominent maxilla and broad parietal, is similar to the closest related species,C.uetzi. Analysis of uncorrected genetic distances within theC.nasutumgroup using the mitochondrial gene ND2 shows a minimum pairwise distance of 11.98% toC.uetzifrom the Sorata massif and Marojejy National Park >500 km north of the type locality ofC.roalokosp. n.. Given an apparently small range (potentially <300 km2), located entirely outside of any nationally-protected areas, we recommend this new species be classified as Endangered under criterion B1ab(iii) of the IUCN Red List. The discovery of clearly distinct species likeC.roalokosp. n.in an area of Madagascar that is comparatively thoroughly surveyed highlights the critical role of continued field surveys for understanding the true extent of Madagascar’s spectacular biodiversity.
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Molecular phylogeny and diversification of Malagasy bright-eyed tree frogs (Mantellidae: Boophis). Mol Phylogenet Evol 2018; 127:568-578. [DOI: 10.1016/j.ympev.2018.05.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 05/20/2018] [Accepted: 05/20/2018] [Indexed: 11/29/2022]
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Molecular detection of Wolbachia pipientis in natural populations of sandfly vectors of Leishmania infantum in endemic areas: first detection in Lutzomyia longipalpis. MEDICAL AND VETERINARY ENTOMOLOGY 2018; 32:111-114. [PMID: 28799248 DOI: 10.1111/mve.12255] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 04/28/2017] [Accepted: 05/15/2017] [Indexed: 06/07/2023]
Abstract
A polymerase chain reaction-based method was used to screen sandflies for infection with Wolbachia (Rickettsiales: Rickettsiaceae), an intracellular bacterial endosymbiont found in many arthropods and filarial hosts. Positive results were obtained in five of 200 field-collected sandflies and were confirmed by sequencing. All sandflies were Lutzomyia longipalpis (Diptera: Psychodidae) captured in a region endemic for visceral leishmaniasis in Brazil. This is the first study to identify Wolbachia infection in this Lutzomyia species, which is the main vector of leishmaniasis in the study area. The low infection rate found in this study (2.5%), together with the lack of detection of Wolbachia in previous studies and the diversity found in the sequences analysed, suggests horizontal transmission to these sandflies.
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Rapid Diversification and Time Explain Amphibian Richness at Different Scales in the Tropical Andes, Earth’s Most Biodiverse Hotspot. Am Nat 2017; 190:828-843. [DOI: 10.1086/694319] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Diamond in the rough: a new species of fossorial diamond frog (Rhombophryne) from Ranomafana National Park, southeastern Madagascar. ZOOSYST EVOL 2017. [DOI: 10.3897/zse.93.10188] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Discovery of a Giant Chameleon-Like Lizard (Anolis) on Hispaniola and Its Significance to Understanding Replicated Adaptive Radiations. Am Nat 2016; 188:357-64. [PMID: 27501092 DOI: 10.1086/687566] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We report a new chameleon-like Anolis species from Hispaniola that is ecomorphologically similar to congeners found only on Cuba. Lizards from both clades possess short limbs and a short tail and utilize relatively narrow perches, leading us to recognize a novel example of ecomorphological matching among islands in the well-known Greater Antillean anole radiation. This discovery supports the hypothesis that the assembly of island faunas can be substantially deterministic and highlights the continued potential for basic discovery to reveal new insights in well-studied groups. Restricted to a threatened band of midelevation transitional forest near the border of the Dominican Republic and Haiti, this new species appears to be highly endangered.
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Corrigendum to “When do species-tree and concatenated estimates disagree? An empirical analysis with higher-level scincid lizard phylogeny”. [Mol. Phylogen. Evol. 82A (2015) 146–155]. Mol Phylogenet Evol 2016; 97:242-243. [DOI: 10.1016/j.ympev.2016.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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A new species of bright-eyed treefrog (Mantellidae) from Madagascar, with comments on call evolution and patterns of syntopy in the Boophis ankaratra complex. Zootaxa 2015; 4034:531-55. [PMID: 26624456 DOI: 10.11646/zootaxa.4034.3.6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Indexed: 11/04/2022]
Abstract
We describe a new species of Boophis treefrog from Ranomafana National Park in the southern central east of Madagascar. This region has remarkably high anuran diversity, and along with neighbouring sites, hosts more than 35 Boophis species. Boophis boppa sp. nov. is part of the B. ankaratra sub-clade (herein named the B. ankaratra complex), previously identified within the monophyletic B. albipunctatus species group. It occurs sympatrically with two other species of the complex (B. ankaratra and B. schuboeae). Morphological differentiation of species within the B. ankaratra clade remains elusive, but species are well characterized by distinct advertisement calls, with B. boppa having the longest note duration and inter-note intervals when compared to closely related species. Furthermore, it has moderate differentiation in mitochondrial DNA, with pairwise distances of 1.9-3.7% to all other species in sequences of the mitochondrial 16S rRNA marker. Additional evidence is given by the lack of haplotype sharing with related species for the nuclear exon DNAH-3. All examples of syntopic occurrence in this complex involve species with strongly different advertisement calls, while allopatric species have more similar calls. Such a pattern might result from adaptive call co-evolution but could also be the result of non-adaptive processes. Thorough clarification of the systematics of the B. ankaratra sub-clade is required, and we outline future directions for both bioacoustic and genetic research.
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Abstract
We report our experience with glenohumeral arthrodesis as a salvage procedure for epilepsy-related recurrent shoulder instability. A total of six patients with epilepsy underwent shoulder fusion for recurrent instability and were followed up for a mean of 39 months (12 to 79). The mean age at the time of surgery was 31 years (22 to 38). Arthrodesis was performed after a mean of four previous stabilisation attempts (0 to 11) in all but one patient in whom the procedure was used as a primary treatment. All patients achieved bony union, with a mean time to fusion of 2.8 months (2 to 7). There were no cases of re-dislocation. One revision was undertaken for loosening of the metalwork, and then healed satisfactorily. An increase was noted in the mean subjective shoulder value, which improved from 37 (5 to 50) pre-operatively to 42 (20 to 70) post-operatively although it decreased in two patients. The mean Oxford shoulder instability score improved from 13 pre-operatively (7 to 21) to 24 post-operatively (13 to 36). In our series, glenohumeral arthrodesis eliminated recurrent instability and improved functional outcome. Fusion surgery should therefore be considered in this patient population. However, since the majority of patients are young and active, they should be comprehensively counselled pre-operatively given the functional deficit that results from the procedure.
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When do species-tree and concatenated estimates disagree? An empirical analysis with higher-level scincid lizard phylogeny. Mol Phylogenet Evol 2014; 82 Pt A:146-55. [PMID: 25315885 DOI: 10.1016/j.ympev.2014.10.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 09/09/2014] [Accepted: 10/02/2014] [Indexed: 02/03/2023]
Abstract
Simulation studies suggest that coalescent-based species-tree methods are generally more accurate than concatenated analyses. However, these species-tree methods remain impractical for many large datasets. Thus, a critical but unresolved issue is when and why concatenated and coalescent species-tree estimates will differ. We predict such differences for branches in concatenated trees that are short, weakly supported, and have conflicting gene trees. We test these predictions in Scincidae, the largest lizard family, with data from 10 nuclear genes for 17 ingroup taxa and 44 genes for 12 taxa. We support our initial predictions, andsuggest that simply considering uncertainty in concatenated trees may sometimes encompass the differences between these methods. We also found that relaxed-clock concatenated trees can be surprisingly similar to the species-tree estimate. Remarkably, the coalescent species-tree estimates had slightly lower support values when based on many more genes (44 vs. 10) and a small (∼30%) reduction in taxon sampling. Thus, taxon sampling may be more important than gene sampling when applying species-tree methods to deep phylogenetic questions. Finally, our coalescent species-tree estimates tentatively support division of Scincidae into three monophyletic subfamilies, a result otherwise found only in concatenated analyses with extensive species sampling.
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Evolution of paedomorphosis in plethodontid salamanders: ecological correlates and re-evolution of metamorphosis. Evolution 2013; 68:466-82. [PMID: 24102140 DOI: 10.1111/evo.12274] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 09/05/2013] [Indexed: 01/08/2023]
Abstract
Life-history modes can profoundly impact the biology of a species, and a classic example is the dichotomy between metamorphic (biphasic) and paedomorphic (permanently aquatic) life-history strategies in salamanders. However, despite centuries of research on this system, several basic questions about the evolution of paedomorphosis in salamanders have not been addressed. Here, we use a nearly comprehensive, time-calibrated phylogeny of spelerpine plethodontids to reconstruct the evolution of paedomorphosis and to test if paedomorphosis is (1) reversible; (2) associated with living in caves; (3) associated with relatively dry climatic conditions on the surface; and (4) correlated with limited range size and geographic dispersal. We find that paedomorphosis arose multiple times in spelerpines. We also find evidence for re-evolution of metamorphosis after several million years of paedomorphosis in a lineage of Eurycea from the Edwards Plateau region of Texas. We also show for the first time using phylogenetic comparative methods that paedomorphosis is highly correlated with cave-dwelling, arid surface environments, and small geographic range sizes, providing insights into both the causes and consequences of this major life history transition.
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Abstract
The sternoclavicular joint (SCJ) is a pivotal articulation in the linked system of the upper limb girdle, providing load-bearing in compression while resisting displacement in tension or distraction at the manubrium sterni. The SCJ and acromioclavicular joint (ACJ) both have a small surface area of contact protected by an intra-articular fibrocartilaginous disc and are supported by strong extrinsic and intrinsic capsular ligaments. The function of load-sharing in the upper limb by bulky periscapular and thoracobrachial muscles is extremely important to the longevity of both joints. Ligamentous and capsular laxity changes with age, exposing both joints to greater strain, which may explain the rising incidence of arthritis in both with age. The incidence of arthritis in the SCJ is less than that in the ACJ, suggesting that the extrinsic ligaments of the SCJ provide greater stability than the coracoclavicular ligaments of the ACJ. Instability of the SCJ is rare and can be difficult to distinguish from medial clavicular physeal or metaphyseal fracture-separation: cross-sectional imaging is often required. The distinction is important because the treatment options and outcomes of treatment are dissimilar, whereas the treatment and outcomes of ACJ separation and fracture of the lateral clavicle can be similar. Proper recognition and treatment of traumatic instability is vital as these injuries may be life-threatening. Instability of the SCJ does not always require surgical intervention. An accurate diagnosis is required before surgery can be considered, and we recommend the use of the Stanmore instability triangle. Most poor outcomes result from a failure to recognise the underlying pathology. There is a natural reluctance for orthopaedic surgeons to operate in this area owing to unfamiliarity with, and the close proximity of, the related vascular structures, but the interposed sternohyoid and sternothyroid muscles are rarely injured and provide a clear boundary to the medial retroclavicular space, as well as an anatomical barrier to unsafe intervention. This review presents current concepts of instability of the SCJ, describes the relevant surgical anatomy, provides a framework for diagnosis and management, including physiotherapy, and discusses the technical challenges of operative intervention.
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Evolution of viviparity: a phylogenetic test of the cold-climate hypothesis in phrynosomatid lizards. Evolution 2013; 67:2614-30. [PMID: 24033171 DOI: 10.1111/evo.12130] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/18/2013] [Indexed: 11/28/2022]
Abstract
The evolution of viviparity is a key life-history transition in vertebrates, but the selective forces favoring its evolution are not fully understood. With >100 origins of viviparity, squamate reptiles (lizards and snakes) are ideal for addressing this issue. Some evidence from field and laboratory studies supports the "cold-climate" hypothesis, wherein viviparity provides an advantage in cold environments by allowing mothers to maintain higher temperatures for developing embryos. Surprisingly, the cold-climate hypothesis has not been tested using both climatic data and phylogenetic comparative methods. Here, we investigate the evolution of viviparity in the lizard family Phrynosomatidae using GIS-based environmental data, an extensive phylogeny (117 species), and recently developed comparative methods. We find significant relationships between viviparity and lower temperatures during the warmest (egg-laying) season, strongly supporting the cold-climate hypothesis. Remarkably, we also find that viviparity tends to evolve more frequently at tropical latitudes, despite its association with cooler climates. Our results help explain this and two related patterns that seemingly contradict the cold-climate hypothesis: the presence of viviparous species restricted to low-elevation tropical regions and the paucity of viviparous species at high latitudes. Finally, we examine whether viviparous taxa may be at higher risk of extinction from anthropogenic climate change.
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Using genomic data to revisit an early example of reproductive character displacement in HaitianAnolislizards. Mol Ecol 2013; 22:3981-95. [DOI: 10.1111/mec.12292] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 02/12/2013] [Accepted: 02/14/2013] [Indexed: 12/14/2022]
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External fixation in the upper limb. Injury 2000; 31 Suppl 1:2. [PMID: 10717267 DOI: 10.1016/s0020-1383(99)00256-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Making history: Thomas Francis, Jr, MD, and the 1954 Salk Poliomyelitis Vaccine Field Trial. ARCHIVES OF PEDIATRICS & ADOLESCENT MEDICINE 2000; 154:512-7. [PMID: 10807305 DOI: 10.1001/archpedi.154.5.512] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
This article focuses on the poliomyelitis vaccine field trial directed by Thomas Francis,Jr, MD, of the University of Michigan Vaccine Evaluation Center and sponsored by the National Foundation for Infantile Paralysis (NFIP) or, as it was better known to the public, the March of Dimes. It was a landmark in the widescale testing of a vaccine and the ethical use of human subjects. Millions of American parents readily volunteered their healthy children to participate. A total of 150,000 volunteers, including schoolteachers, physicians, nurses, and health officers all endorsed the study and donated their time and effort to make it successful. Avoiding the use of marginalized groups, the field trial purposefully did not involve institutionalized children; instead, it was based in 15,000 public schools in 44 of the 48 states as clinic sites. A group of 650,000 children received some type of injection, either the vaccine or a placebo, and another 1.18 million served as controls. The field trial depended, most essentially, on both public support and the participation of millions of children who remained enrolled in a study that required a series of 3 injections and a 6-month evaluation period. Enlisting the huge number of participants presented practical examples of the difficulties in experimenting on human subjects. On April 26, 1954, Randy Kerr, a participant or "Polio Pioneer" as the children involved were called, received the first inoculation of the Salk poliomyelitis vaccine. The nationwide study "designed to test the safety and efficacy" of the Salk vaccine had officially begun.
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Abstract
The timing of soft-tissue reconstruction for severe open fractures of the lower leg is considered crucial to the later outcome, and yet pertinent publications are few. The purpose of this study was to add some based on evidence arguments for the choice of the most adequate timing in the management of these injuries. Twenty-nine consecutive open fractures of the tibia, including 24 grade 3B and 5 grade 3C fractures, were treated using a protocol of immediate debridement, early definitive skeletal stabilisation and early soft-tissue reconstruction. Fifteen lower legs were reconstructed after a mean delay of 4.4 days (range 1-9 days), while 14 lower legs were reconstructed immediately, i.e. as an emergency procedure on the day of admission. Both groups were comparable for sex, age, type of trauma, associated general injuries, type of fracture, associated arterial lesion, associated tendon rupture, type of soft-tissue reconstruction and duration of follow-up. All patients were reviewed at a mean follow-up of 47 months (range 15-89 months). In the delayed reconstruction group the time to full, unprotected weight-bearing (P = 0.0021), the time to definitive union (P = 0.0049), the number of reoperations (P = 0.0001) and the infection rate (P = 0.0374) were significantly higher. The data suggest that immediate reconstruction is, the general condition of the patient permitting, the timing of choice for soft-tissue coverage.
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Abstract
Between 1968 and 1995, 37 patients with ununited fractures of the clavicle were treated by decortication and plate osteosynthesis. Thirty-two (86%) were failures of union of fractures of the middle third. Thirty-four (92%) patients had post-traumatic nonunion or delayed union. Sixteen (43%) patients had undergone primary operative treatment. Autogenous cancellous bone graft was used in 24 (65%) patients with atrophic nonunion. Nine tricortical, iliac crest, intercalary grafts were used for segmental bone loss equal to or greater than 15 mm. At the end of treatment, union had been achieved in 35 (95%) cases. At a mean follow-up of 8.6 years (range 13 months to 17 years), 32 (86%) patients had no symptoms and had a full range of motion of the shoulder. Decortication with plate osteosynthesis is a reliable, durable technique for the management of symptomatic, ununited fractures of the clavicle.
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Abstract
The deltoid extension lag sign has been developed to avoid the pitfalls confounding the diagnosis of an axillary nerve lesion. The physician elevates the arm into a position of near full extension. The patient is asked to attempt active maintenance of this position. If the deltoid is weak, the arm will drop. In five patients with traumatic axillary nerve palsy after anterior dislocation of the shoulder, the deltoid extension lag sign was used to evaluate the functional status of the deltoid muscle. The magnitude of the angular drop, or lag, of the arm was a precise indicator of the functional status and recovery of the deltoid. The sign proved to be objective and reproducible, allowing confident assessment of deltoid function and when repeated over time allowed precise follow-up of deltoid recovery.
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Absence of avascular necrosis of the humeral head after post-traumatic rupture of the anterior and posterior humeral circumflex arteries. A case report. J Bone Joint Surg Am 1996; 78:1256-9. [PMID: 8753720 DOI: 10.2106/00004623-199608000-00018] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Allograft reconstruction of segmental defects of the humeral head for the treatment of chronic locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1996; 78:376-82. [PMID: 8613444 DOI: 10.2106/00004623-199603000-00008] [Citation(s) in RCA: 217] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The recognized options for the treatment of chronic locked posterior dislocation of the shoulder are dependent on the size of the anteromedial defect of the humeral head. Transfer of the lesser tuberosity with its attached subscapularis tendon into the defect is recommended for defects that are smaller than approximately 40 per cent of the joint surface. Prosthetic replacement is preferred for larger defects. Four consecutive patients who had a chronic locked posterior dislocation of the glenohumeral joint associated with a defect of the humeral head that was at least 40 per cent of the articular surface were managed with reconstruction of the shape of the humeral head with use of an allogeneic segment of the femoral head. Stability was restored and maintained in each patient at an average of sixty-eight months (range, sixty to seventy-six months) after the procedure. Three patients reported little or no pain and no or slight functional restrictions in the activities of daily living, and they considered the result to be satisfactory. The fourth patient had mild pain and moderate-to-severe dysfunction secondary to avascular necrosis of the remaining portion of the humeral head after a symptom-free period of six years.
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Fractures of the humeral capitellum: Herbert screw fixation. JOURNAL OF THE ROYAL COLLEGE OF SURGEONS OF EDINBURGH 1994; 39:321-3. [PMID: 7861347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
During the first half of 1991, five patients with displaced fractures of the humeral capitellum were managed by open reduction and fixation of the capitellar fragments with Herbert bone screws. All patients had stable, painfree elbows at follow-up, with no restriction of normal daily activities. There were no evidence of early avascular necrosis of capitellar fragments, even where soft tissue attachments of small fragments had been injured. This method of fixation allows accurate restoration of the articular surface of the humero-radial joint and may therefore contribute to the excellent functional results following this injury in these patients.
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Abstract
A total of 21 consecutive referrals with multiple injuries (Injury Severity Score (ISS) 17-66), admitted into the Regional Neurosurgical Unit (RNSU) over a 1-year period from August 1989, was analysed to evaluate the risks associated with transfer of such patients from district general hospitals within the North West Thames Region. Injury assessment was deficient in nine cases. Four developed hypovolaemic shock during transfer, and in five resuscitation was inadequate. Four had minor head injuries and two had no head injury; of these cases, one died. There were four fatalities: the mean ISS in this group was 42, and in all cases deficiencies in resuscitation and assessment before transfer were identified. There were seven major missed injuries. All patients had musculoskeletal injuries and 16 required orthopaedic intervention within 6 h. Interhospital transfer of this group of patients carries significant risks, may be unnecessary, and may delay other surgical priorities.
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Modification of guanine nucleotide-regulatory components in brain membranes. I. Changes in guanosine 5'-triphosphate regulation of opiate receptor-binding sites. J Neurosci 1984; 4:2755-63. [PMID: 6094741 PMCID: PMC6564730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Guanine nucleotides regulate binding of opiate agonists to membrane receptors by increasing agonist dissociation rates. The current study demonstrates that the ability of guanosine 5'-triphosphate (GTP) and its nonhydrolyzable analogue guanylyl-5'-imidodiphosphate (Gpp(NH)p) to inhibit opiate agonist binding to rat brain membranes can be altered by two methods: by preincubating with EDTA, and by preincubating at pH 4.5. EDTA pretreatment increased the potency of Gpp(NH)p in inhibiting [3H]morphine binding by 4-fold, with little apparent change in the maximum effect of Gpp(NH)p or on levels of binding itself. The effect of EDTA pretreatment was blocked by prior incubation of membranes with excess calcium or manganese but could not be reversed by any divalent cation if the EDTA incubation was longer than 10 min. EDTA pretreatment increased the effects of GTP on dissociation rates of agonists. Pretreatment of membranes at pH 4.5 increased the ability of guanine nucleotides to regulate agonist binding by increasing the maximum effect of Gpp(NH)p from 50% to 80% inhibition of [3H]morphine binding with minor increase in potency of Gpp(NH)p. The actions of EDTA and low pH pretreatments were additive when both were conducted on the same membranes. These results suggest that modification of brain membranes can alter the interaction of receptors with guanine nucleotide-regulatory components which may lead to changes in post-receptor membrane events.
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Selective alterations in guanine nucleotide regulation of opiate receptor binding and coupling with adenylate cyclase. Life Sci 1983; 33 Suppl 1:215-8. [PMID: 6319864 DOI: 10.1016/0024-3205(83)90481-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Pretreatment of rat brain membranes at pH 4.5 increased GTP and Gpp(NH)p regulation of [3H]-D-ala2-met5-enkephalinamide (D-ala-enk) binding with no change in absolute binding itself. Pretreatment at pH 4.5 did not alter basal adenylate cyclase activity but did cause a loss (50-90%) in NaF- and Gpp(NH)p-stimulated activity, indicating a functional loss of GTP-coupling proteins. The addition of cis-vaccenic acid partially restored NaF- and Gpp(NH)p-stimulated cyclase after low pH pretreatment but, in the same membranes, did not reverse the increase in GTP regulation of agonist binding. These results suggest that GTP regulation of binding and stimulation of adenylate cyclase occur by fundamentally different mechanisms.
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Inhibition of brain cholinesterase by organophosphorus compounds in rats. ARCHIVES INTERNATIONALES DE PHARMACODYNAMIE ET DE THERAPIE 1971; 192:48-60. [PMID: 5093191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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