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1.
Zootaxa ; 5174(5): 508-524, 2022 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-36095385

RESUMEN

A new seasonal killifish of the genus Nothobranchius is described from the Montepuez River system in northern Mozambique. The new species, Nothobranchius balamaensis Bragana Chakona, is differentiated from congeners by its characteristic colour pattern and molecular data further support its taxonomic distinctiveness. Phylogenetic results based on two mitochondrial and three nuclear genes confirms N. balamaensis is closely related to N. kirki and N. wattersi; all three belonging to the Coastal-Inland Clade. The new species is most similar in colour pattern to N. kirki sharing the characteristic of a deep red-orange colouration in the basal, proximal, and medial zones of the caudal and anal fins that grades to orange in the distal zone. This is a key feature that distinguishes these two species from all other Nothobranchius. The main distinguishing features between the new species and N. kirki is the presence of a light blue to white band or series of irregular markings in the proximal zone of the anal fin in N. kirki, versus the absence of such a colour pattern element in N. balamaensis, as well as differences in the dorsal fin pattern. When compared to all population groups of N. wattersi, the colour pattern of N. balamaensis is distinctive. Nothobranchius balamaensis is a relatively slender member of the genus, a characteristic that clearly distinguishes it from both N. kirki and N. wattersi. Nothobranchius balamaensis is currently only known from a few specimens from the type locality.


Asunto(s)
Ciprinodontiformes , Fundulidae , Animales , Mozambique , Filogenia , Ríos
2.
Mol Phylogenet Evol ; 158: 106988, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33059071

RESUMEN

This paper reports a phylogeny of the African killifishes (Genus Nothobranchius, Order Cyprinodontiformes) informed by five genetic markers (three nuclear, two mitochondrial) of 80 taxa (seven undescribed and 73 of the 92 recognized species). These short-lived annual fishes occupy seasonally wet habitats in central and eastern Africa, and their distribution coincides largely with the East African Rift System (EARS). The fossil dates of sister clades used to constrain a chronometric tree of all sampled Nothobranchius recovered the origin of the genus at ~13.27 Mya. It was followed by the radiations of six principal clades through the Neogene. An ancestral area estimation tested competing biogeographical hypotheses to constrain the ancestral origin of the genus to the Nilo-Sudan Ecoregion, which seeded a mid-Miocene dispersal event into the Coastal ecoregion, followed closely (~10 Mya) by dispersals southward across the Mozambique coastal plain into the Limpopo Ecoregion. Extending westwards across the Tanzanian plateau, a pulse of radiations through the Pliocene were associated with dispersals and fragmentation of wetlands across the Kalahari and Uganda Ecoregions. We interpret this congruence of drainage rearrangements with dispersals and cladogenic events of Nothobranchius to reflect congruent responses to recurrent uplift and rifting. The coevolution of these freshwater fishes and wetlands is attributed to ultimate control by tectonics, as the EARS extended southwards during the Neogene. Geobiological consilience of the combined evidence supports a tectonic hypothesis for the evolution of Nothobranchius.


Asunto(s)
Genoma , Peces Killi/clasificación , África , Animales , Núcleo Celular/genética , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Glicosiltransferasas/clasificación , Glicosiltransferasas/genética , Peces Killi/genética , Mitocondrias/genética , Filogenia , Filogeografía , Análisis de Secuencia de ADN
3.
Clin Oncol (R Coll Radiol) ; 32(11): 704-712, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32826132

RESUMEN

One of the greatest successes of radiotherapy has been its ability to palliate symptoms from advanced and metastatic cancers. Unfortunately, patients face barriers to accessing care and the demand for treatment is rising. Rapid access palliative radiotherapy programmes were created in response to these concerns, and over time they have proliferated and succeeded internationally. This narrative review provides an overview of programmes that have published their experiences, and discusses how they have improved access to care, increased evidence-based practice, met the needs of vulnerable populations, advanced the roles of multidisciplinary team members, collaborated across medical specialties, educated trainees and referring physicians, and developed new treatment platforms using advanced technologies.


Asunto(s)
Neoplasias/radioterapia , Cuidados Paliativos/métodos , Oncología por Radiación/métodos , Humanos
5.
Biol Rev Camb Philos Soc ; 93(1): 115-130, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28429851

RESUMEN

We review the state of African ungulate taxonomy over the last 120 years, with an emphasis on the introduction of the polytypic species concept and the discipline's general neglect since the middle of the 20th century. We single out negative consequences of 'orthodox' taxonomy, highlighting numerous cases of neglect of threatened lineages, unsound translocations that led to lineage introgression, and cases of maladaptation to local conditions including parasitic infections. Additionally, several captive breeding programmes have been hampered by chromosome rearrangements caused by involuntary lineage mixing. We advocate that specimen-based taxonomy should regain its keystone role in mammal research and conservation biology, with its scientific values augmented with genomic evidence. While integration with molecular biology, ecology and behaviour is needed for a full understanding of ungulate alpha diversity, we stress that morphological diversity has been neglected despite its tremendous practical importance for some groups of 'utilizers' such as trophy hunters, wildlife tourists and conservationists. We conclude that there is no evidence that purported 'taxonomic inflation' has adverse effects on ungulate conservation: rather, it is taxonomic inertia that has such adverse effects. We stress that sound science, founded on robust taxonomy, should underpin effective sustainable management (hunting, ranching, captive breeding and reintroduction programmes) of this unique African natural resource.


Asunto(s)
Artiodáctilos/clasificación , Artiodáctilos/fisiología , Biodiversidad , Conservación de los Recursos Naturales , África , Animales
6.
Bone Joint J ; 99-B(11): 1496-1501, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29092989

RESUMEN

AIMS: There has been an evolution recently in the management of unstable fractures of the ankle with a trend towards direct fixation of a posterior malleolar fragment. Within these fractures, Haraguchi type 2 fractures extend medially and often cannot be fixed using a standard posterolateral approach. Our aim was to describe the posteromedial approach to address these fractures and to assess its efficacy and safety. PATIENTS AND METHODS: We performed a review of 15 patients with a Haraguchi type 2 posterior malleolar fracture which was fixed using a posteromedial approach. Five patients underwent initial temporary spanning external fixation. The outcome was assessed at a median follow-up of 29 months (interquartile range (IQR) 17 to 36) using the Olerud and Molander score and radiographs were assessed for the quality of the reduction. RESULTS: The median Olerud and Molander score was 72 (IQR 70 to 75), representing a good functional outcome. The reduction was anatomical in ten, with a median step of 1.2 mm (IQR 0.9 to 1.85) in the remaining five patients. One patient had parasthaesiae affecting the medial forefoot, which resolved within three months. CONCLUSION: We found that the posteromedial approach to the ankle for the surgical treatment of Haraguchi type 2 posterior malleolar fractures is a safe technique that enables good visualisation and reduction of the individual fracture fragments with promising early outcomes. Cite this article: Bone Joint J 2017;99-B:1496-1501.


Asunto(s)
Fracturas de Tobillo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas Cerradas/cirugía , Adulto , Fracturas de Tobillo/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Fracturas Cerradas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
7.
Nature ; 547(7662): 162, 2017 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-28703184
8.
Bone Joint J ; 98-B(7): 1003-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27365481

RESUMEN

AIMS: Although infrequent, a fracture of the cuboid can lead to significant disruption of the integrity of the midfoot and its function. The purpose of this study was to classify the pattern of fractures of the cuboid, relate them to the mechanism of injury and suggest methods of managing them. PATIENTS AND METHODS: We performed a retrospective review of patients with radiologically reported cuboid fractures. Fractures were grouped according to commonly occurring patterns of injury. A total of 192 fractures in 188 patients were included. They were classified into five patterns of injury. RESULTS: Type 1 fractures (93 fractures, 48.4%) are simple avulsion injuries involving the capsule of the calcaneo-cuboid joint. Type 2 fractures (25 fractures, 13%) are isolated extra-articular injuries involving the body of the cuboid. Type 3 injuries (13 factures, 6.8%) are intra-articular fractures solely within the body of the cuboid. Type 4 fractures (35 fractures, 18.2%) are associated with disruption of the midfoot and tarsometatarsal injuries. Type 5 fractures (26 fractures, 13.5%) occur in conjunction with disruption of the mid-tarsal joint and either crushing of the lateral column alone or of both medial and lateral columns. Fractures with significant articular disruption or with loss of length of the lateral column underwent fixation. This involved either internal fixation to restore the anatomy of the cuboid and/or restoration of the length of the columns with bridging constructs using internal or external fixation. CONCLUSION: A classification system for fractures of the cuboid is proposed in relation to the mechanism of injury. The treatment of these fractures is described. Cite this article: Bone Joint J 2016;98-B:1003-8.


Asunto(s)
Fracturas Óseas/clasificación , Fracturas Óseas/terapia , Huesos Tarsianos/lesiones , Huesos Tarsianos/cirugía , Fijación Interna de Fracturas , Fracturas Óseas/diagnóstico por imagen , Humanos , Estudios Retrospectivos , Huesos Tarsianos/diagnóstico por imagen , Centros Traumatológicos
9.
J Hered ; 107(2): 101-3, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26695079

RESUMEN

South-central Africa is characterized by an archipelago of wetlands, which has evolved in time and space since at least the Miocene, providing refugia for animal species during Pleistocene arid episodes. Their importance for biodiversity in the region is reflected in the evolution of a variety of specialist mammal and bird species, adapted to exploit these wetland habitats. Populations of lions (Panthera leo) across south-central and east Africa have contrasting signatures of mitochondrial DNA haplotypes and biparental nuclear DNA in wetland and savannah habitats, respectively, pointing to the evolution of distinct habitat preferences. This explains the absence of genetic admixture of populations from the Kalahari savannah of southwest Botswana and the Okavango wetland of northern Botswana, despite separation by only 500 km. We postulate that ancestral lions were wetland specialists and that the savannah lions evolved from populations that were isolated during arid Pleistocene episodes. Expansion of grasslands and the resultant increase in herbivore populations during mesic Pleistocene climatic episodes provided the stimulus for the rapid population expansion and diversification of the highly successful savannah lion specialists. Our model has important implications for lion conservation.


Asunto(s)
Variación Genética , Genética de Población , Pradera , Leones/genética , Humedales , Animales , Botswana , Conservación de los Recursos Naturales , ADN Mitocondrial/genética , Evolución Molecular , Haplotipos
10.
PLoS One ; 10(9): e0137847, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26422465

RESUMEN

In the context of molecularly-dated phylogenies, inferences informed by ancestral habitat reconstruction can yield valuable insights into the origins of biomes, palaeoenvironments and landforms. In this paper, we use dated phylogenies of 12 plant clades from the Cape Floristic Region (CFR) in southern Africa to test hypotheses of Neogene climatic and geomorphic evolution. Our combined dataset for the CFR strengthens and refines previous palaeoenvironmental reconstructions based on a sparse, mostly offshore fossil record. Our reconstructions show remarkable consistency across all 12 clades with regard to both the types of environments identified as ancestral, and the timing of shifts to alternative conditions. They reveal that Early Miocene land surfaces of the CFR were wetter than at present and were dominated by quartzitic substrata. These conditions continue to characterize the higher-elevation settings of the Cape Fold Belt, where they have fostered the persistence of ancient fynbos lineages. The Middle Miocene (13-17 Ma) saw the development of perennial to weakly-seasonal arid conditions, with the strongly seasonal rainfall regime of the west coast arising ~6.5-8 Ma. Although the Late Miocene may have seen some exposure of the underlying shale substrata, the present-day substrate diversity of the CFR lowlands was shaped by Pliocene-Pleistocene events. Particularly important was renewed erosion, following the post-African II uplift episode, and the reworking of sediments on the coastal platform as a consequence of marine transgressions and tectonic uplift. These changes facilitated adaptive radiations in some, but not all, lineages studied.


Asunto(s)
Evolución Biológica , Clima , Ecosistema , Fósiles , Filogenia , Plantas/clasificación , África Austral , Biodiversidad , Flores/clasificación , Fósiles/historia , Historia Antigua , Fenómenos Fisiológicos de las Plantas , Lluvia , Estaciones del Año
11.
PLoS One ; 10(4): e0125043, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25928886

RESUMEN

A long history of research focused on the East Africa cichlid radiations (EAR) revealed discrepancies between mtDNA and nuclear phylogenies, suggesting that interspecific hybridisation may have been significant during the radiation of these fishes. The approximately 250 cichlid species of Lake Tanganyika have their roots in a monophyletic African cichlid assemblage, but controversies remain about the precise phylogenetic origin and placement of different lineages and consequently about L. Tanganyika colonization scenarios. 3312 AFLP loci and the mitochondrial ND2 gene were genotyped for 91 species representing almost all major lacustrine and riverine haplotilapiine east African cichlid lineages with a focus on L. Tanganyika endemics. Explicitly testing for the possibility of ancient hybridisation events, a comprehensive phylogenetic network hypothesis is proposed for the origin and diversification of L. Tanganyika cichlids. Inference of discordant phylogenetic signal strongly suggests that the genomes of two endemic L. Tanganyika tribes, Eretmodini and Tropheini, are composed of an ancient mixture of riverine and lacustrine lineages. For the first time a strong monophyly signal of all non-haplochromine mouthbrooding species endemic to L. Tanganyika ("ancient mouthbrooders") was detected. Further, in the genomes of early diverging L. Tanganyika endemics Trematocarini, Bathybatini, Hemibatini and Boulengerochromis genetic components of other lineages belonging to the East African Radiation appear to be present. In combination with recent palaeo-geological results showing that tectonic activity in the L. Tanganyika region resulted in highly dynamic and heterogeneous landscape evolution over the Neogene and Pleistocene, the novel phylogenetic data render a single lacustrine basin as the geographical cradle of the endemic L. Tanganyika cichlid lineages unlikely. Instead a scenario of a pre-rift origin of several independent L. Tanganyika precursor lineages which diversified in ancient rivers and precursor lakes and then amalgamated in the extant L. Tanganyika basin is put forward as an alternative: the 'melting pot Tanganyika' hypothesis.


Asunto(s)
Cíclidos/genética , Animales , Cíclidos/clasificación , ADN Mitocondrial/genética , Genotipo , Lagos , Filogenia
12.
Foot Ankle Surg ; 20(4): 268-71, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25457664

RESUMEN

BACKGROUND: Hindfoot nails are being increasingly used, however significant complications can occur. The purpose of this study was to assess the complications following the use of hindfoot nails at our institution. METHODS: We identified patients from a retrospective database. All underwent hindfoot nailing under the care of the senior author. Details of complications were recorded. RESULTS: We identified 52 patients undergoing 55 procedures. Mean follow up was 44.8 months (18-69). Forty patients achieved ankle fusion and 36 subtalar joint fusion. Complications included prominent metalwork in 13 patients, CRPS in five and one peri-prosthetic fracture. Nine developed deep infection, and of these limb salvage was achieved in six patients by removal of metalwork, debridement and insertion of antibiotic loaded cement beads. The remaining three patients underwent below knee amputation. CONCLUSION: Significant complications can occur, although limb preservation was possible in most cases of deep infection. Hindfoot nailing should be reserved as salvage procedure.


Asunto(s)
Articulación del Tobillo/cirugía , Artrodesis/instrumentación , Clavos Ortopédicos/efectos adversos , Calcáneo/cirugía , Articulación Talocalcánea/cirugía , Astrágalo/cirugía , Tibia/cirugía , Adulto , Anciano , Amputación Quirúrgica/estadística & datos numéricos , Antibacterianos/administración & dosificación , Cementos para Huesos , Síndromes de Dolor Regional Complejo/etiología , Desbridamiento , Remoción de Dispositivos , Estudios de Seguimiento , Humanos , Recuperación del Miembro , Persona de Mediana Edad , Fracturas Periprotésicas/etiología , Infecciones Relacionadas con Prótesis/etiología , Infecciones Relacionadas con Prótesis/terapia , Estudios Retrospectivos , Adulto Joven
13.
Strategies Trauma Limb Reconstr ; 9(1): 33-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24519370

RESUMEN

The management of tibial non-union is challenging with protracted, often arduous, treatments. The purpose of this study was to assess patient-reported outcomes following treatment of tibial non-union in circular external fixators. Twenty-one patients with tibial non-unions who successfully completed treatment at a mean of 10.1 months (range 6-20) in a circular external fixator were sent questionnaires utilising the Enneking scoring system and Euroqol EQ-5D. There were 14 responses. The mean Enneking score was 58.0 % (34.3-77.1). Two patients were enthusiastic about their treatment, while three accepted but would not repeat the treatment. The Euroqol questionnaire found that 8 patients had difficulty with mobility, 10 had difficulty with usual activities and 12 had moderate pain. There was no statistically significant difference in the EQ VAS score of overall health state for treated patients compared with predicted scores for an age- and sex-matched UK population (77.7 vs 83.1, p = 0.07).

15.
Anaesthesia ; 68(11): 1199, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24128028
16.
Diversity (Basel) ; 5(2): 374-392, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24072980

RESUMEN

Although constituting more than 100,000 described species, protists are virtually ignored within the arena of biodiversity conservation. One reason is the widespread belief that the majority of protists have cosmopolitan distributions, in contrast to the highly hetereogenous biogeography of the "mega-Metazoa". However, modern research reveals that about one third of the known protists have restricted distributions, which endorses their conservation, at least in special cases. Here, we report what probably ranks as the first successful conservation intervention focused directly on known protist diversity. It is justified by unique species, type localities, and landscape maintenance as evidence for legislation. The protected habitat comprises an ephemeral pond, which is now a "Natural Monument" for ciliated protozoa. This wetland occupies a natural depression on the Krauthügel ("cabbage hill") south of the fortress of Salzburg City. When filled, the claviform pond has a size of ~30 × 15 m and a depth rarely surpassing 30 cm. Water is present only for some days or weeks, depending on heavy and/or prolonged rain. The pond occupied an agricultural field where root and leafy vegetables were cultivated for possibly more than 200 years. In the 1960s, this area became a grassland utilized as an autumn pasture, but was abandoned in the 1990s. Repeated sampling between 1982 and 2012 recovered a total of at least 150 ciliate taxa, of which 121 were identified to species level. Eight species were new to science, and an additional 10 poorly known species were reinvestigated and neotypified with populations from the Krauthügel pond. Both endemism and type localities justify the argument that the "integrative approach" in biodiversity and conservation issues should include protists and micro-metazoans. We argue that Krauthügel holds a unique reference node for biodiversity inventories to obtain the baseline knowledge-which is the prerequisite to monitor ecosystem integrity-and detect and evaluate impacts of natural and anthropogenic disturbances.

17.
Anaesth Intensive Care ; 41(2): 163-74, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23530783

RESUMEN

Patient inflating valves combined with self-inflating bags are known to all anaesthetists as resuscitation devices and are familiar as components of draw-over anaesthesia systems. Their variants are also commonplace in transfer and home ventilators. However, the many variations in structure and function have led to difficulties in their optimal use, definition and classification. After reviewing the relevant literature, we defined a patient inflating valve as a one-way valve that closes an exit port to enable lung inflation, also permitting exhalation and spontaneous breathing, the actions being automatic. We present a new classification based on the mechanism of valve opening/closure; namely elastic recoil of a flexible flap/diaphragm, sliding spindle opened by a spring/magnet or a hollow balloon collapsed by external pressure. The evolution of these valves has been driven by the difficulties documented in critical incidents, which we have used along with information from modern International Organization for Standardization standards to identify 13 ideal properties, the top six of which are non-jamming, automatic, no bypass effect, no rebreathing or air entry at patient end, low resistance, robust and easy to service. The Ambu and the Laerdal valves have remained popular due to their simplicity and reliability. Two new alternatives, the Fenton and Diamedica valves, offer the benefits of location away from the patient while retaining a small functional dead space. They also offer the potential for greater use of hybrid continuous flow/draw-over systems that can operate close to atmospheric pressure. The reliable application of positive end-expiratory pressure/continuous positive airway pressure remains a challenge.


Asunto(s)
Anestesiología/instrumentación , Resucitación/instrumentación , Falla de Equipo , Humanos , Respiración con Presión Positiva
19.
Anaesthesia ; 67(10): 1181; author reply 1181-2, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22950407
20.
PLoS One ; 7(9): e41744, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22984399

RESUMEN

Gigantism and dwarfism evolve in vertebrates restricted to islands. We describe four new species in the Rhinolophus hildebrandtii species-complex of horseshoe bats, whose evolution has entailed adaptive shifts in body size. We postulate that vicissitudes of palaeoenvironments resulted in gigantism and dwarfism in habitat islands fragmented across eastern and southern Africa. Mitochondrial and nuclear DNA sequences recovered two clades of R. hildebrandtii senso lato which are paraphyletic with respect to a third lineage (R. eloquens). Lineages differ by 7.7 to 9.0% in cytochrome b sequences. Clade 1 includes R. hildebrandtii sensu stricto from the east African highlands and three additional vicariants that speciated across an Afromontane archipelago through the Plio-Pleistocene, extending from the Kenyan Highlands through the Eastern Arc, northern Mozambique and the Zambezi Escarpment to the eastern Great Escarpment of South Africa. Clade 2 comprises one species confined to lowland savanna habitats (Mozambique and Zimbabwe). A third clade comprises R. eloquens from East Africa. Speciation within Clade 1 is associated with fixed differences in echolocation call frequency, and cranial shape and size in populations isolated since the late Pliocene (ca 3.74 Mya). Relative to the intermediate-sized savanna population (Clade 2), these island-populations within Clade 1 are characterised by either gigantism (South African eastern Great Escarpment and Mts Mabu and Inago in Mozambique) or dwarfism (Lutope-Ngolangola Gorge, Zimbabwe and Soutpansberg Mountains, South Africa). Sympatry between divergent clades (Clade 1 and Clade 2) at Lutope-Ngolangola Gorge (NW Zimbabwe) is attributed to recent range expansions. We propose an "Allometric Speciation Hypothesis", which attributes the evolution of this species complex of bats to divergence in constant frequency (CF) sonar calls. The origin of species-specific peak frequencies (overall range = 32 to 46 kHz) represents the allometric effect of adaptive divergence in skull size, represented in the evolution of gigantism and dwarfism in habitat islands.


Asunto(s)
Evolución Biológica , Tamaño Corporal , Quirópteros/anatomía & histología , Quirópteros/genética , Variación Genética , Islas , Acústica , África , Animales , Tamaño Corporal/genética , Quirópteros/clasificación , Citocromos b/genética , Bases de Datos Genéticas , Enanismo/genética , Enanismo/veterinaria , Ecolocación , Femenino , Genotipo , Geografía , Gigantismo/genética , Gigantismo/veterinaria , Masculino , Datos de Secuencia Molecular , Filogenia , Análisis de Componente Principal , Factores de Tiempo
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