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1.
J Hum Evol ; 141: 102727, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32078931

RESUMO

Paranthropus boisei was first described in 1959 based on fossils from the Olduvai Gorge and now includes many fossils from Ethiopia to Malawi. Knowledge about its postcranial anatomy has remained elusive because, until recently, no postcranial remains could be reliably attributed to this taxon. Here, we report the first associated hand and upper limb skeleton (KNM-ER 47000) of P. boisei from 1.51 to 1.53 Ma sediments at Ileret, Kenya. While the fossils show a combination of primitive and derived traits, the overall anatomy is characterized by primitive traits that resemble those found in Australopithecus, including an oblique scapular spine, relatively long and curved ulna, lack of third metacarpal styloid process, gracile thumb metacarpal, and curved manual phalanges. Very thick cortical bone throughout the upper limb shows that P. boisei had great upper limb strength, supporting hypotheses that this species spent time climbing trees, although probably to a lesser extent than earlier australopiths. Hand anatomy shows that P. boisei, like earlier australopiths, was capable of the manual dexterity needed to create and use stone tools, but lacked the robust thumb of Homo erectus, which arguably reflects adaptations to the intensification of precision grips and tool use. KNM-ER 47000 provides conclusive evidence that early Pleistocene hominins diverged in postcranial and craniodental anatomy, supporting hypotheses of competitive displacement among these contemporaneous hominins.


Assuntos
Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Extremidade Superior/anatomia & histologia , Animais , Quênia
3.
J Hum Evol ; 116: 27-42, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29477180

RESUMO

Archaeological excavations at the DK site in the eastern Olduvai Basin, Tanzania, age-bracketed between ∼1.88 Ma (Bed I Basalt) and ∼1.85 Ma (Tuff IB), record the oldest lahar inundation, modification, and preservation of a hominin "occupation" site yet identified. Our landscape approach reconstructs environments and processes at high resolution to explain the distribution and final preservation of archaeological materials at the DK site, where an early hominin (likely Homo habilis) assemblage of stone tools and bones, found close to hominin specimens OH24 and OH56, developed on an uneven heterogeneous surface that was rapidly inundated by a lahar and buried to a depth of 0.4-1.2 m (originally ∼1.0-2.4 m pre-compaction). The incoming intermediate to high viscosity mudflow selectively modified the original accumulation of "occupation debris," so that it is no longer confined to the original surface. A dispersive debris "halo" was identified within the lahar deposit: debris is densest immediately above the site, but tails off until not present >150 m laterally. Voorhies indices and metrics derived from limb bones are used to define this dispersive halo spatially and might indicate a possible second assemblage to the east that is now eroded away. Based upon our new data and prior descriptions, two possibilities for the OH24 skull are suggested: it was either entrained by the mudflow from the DK surface and floated due to lower density toward its top, or it was deposited upon the solid top surface after its consolidation. Matrix adhering to material found in association with the parietals indicates that OH56 at least was relocated by the mudflow.


Assuntos
Arqueologia , Meio Ambiente , Hominidae , Erupções Vulcânicas , Animais , Fósseis , Sedimentos Geológicos/análise , Paleontologia , Tanzânia
4.
Diabet Med ; 35(1): 53-62, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29023974

RESUMO

AIMS: To investigate the relationship between high diabetes-related lower limb amputation incidence and foot care services in the South-West region of England. METHODS: The introduction of 10 key elements of foot care service provision in one area of the South-West resulted in stabilization of foot ulcer incidence and sustained reduction in amputation incidence from 2007. Services introduced included administrative support, standardized general practice foot screening, improved community podiatry staffing, hospital multidisciplinary foot clinics, effective care pathways, availability of an orthotist and audit. Peer reviews of the region's diabetes foot care services were undertaken to assess delivery of these service provisions and compare this with major amputation incidence in other regions with data provided by Yorkshire and Humber Public Health Observatory Hospital Episode Statistics. Recommendations were made to improve service provision. In 2015 changes in service provision and amputation incidence were reviewed. RESULTS: Initial reviews in 2013 showed that the 3-year diabetes-related major amputation incidence correlated inversely with adequate delivery of diabetes foot care services (P=0.0024, adjusted R2 =0.51). Repeat reviews in 2015 found that two or more foot care service improvements were reported by six diabetes foot care providers, with improvement in outcomes. The negative relationship between major amputation incidence and service provision remained strong both in the period 2012-2015 and in the year 2015 only (P ≤0.0012, adjusted R2 =0.56, and P= 0.0005, R2 =0.62, respectively). CONCLUSIONS: Major diabetes-related lower limb amputation incidence is significantly inversely correlated with foot care services provision. Introduction of more effective service provision resulted in significant reductions in major amputation incidence within 2 years. Failure to improve unsatisfactory service provision resulted in continued high amputation incidence.


Assuntos
Amputação Cirúrgica/estatística & dados numéricos , Pé Diabético/terapia , Serviços de Saúde , Extremidade Inferior/cirurgia , Idoso , Atenção à Saúde , Pé Diabético/epidemiologia , Gerenciamento Clínico , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Revisão por Pares , Prevalência , Qualidade da Assistência à Saúde , Medicina Estatal
7.
Eye (Lond) ; 27(1): 78-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23154501

RESUMO

AIM: (1) To investigate the recurrence of periocular basal cell carcinoma (BCC) reported as completely excised on histology. (2) To identify risks associated with recurrence. (3) To recommend a rational follow-up protocol. METHODS: This is a cohort study by case note review of consecutive patients undergoing excision of periocular BCC between 2000 and 2006 at University Hospitals of Leicester. All lesions were excised with 3 mm clinical margin and the defect reconstructed only after the excision margin was declared clear. RESULTS: A total of 413 episodes of surgical excision were recorded for 270 patients over the 7-year period of 2000-2006. All of them have 5 years follow-up. Mean age 73.7 (±12.5). In all, 67% were nodular BCC and 45.4% located in the lower eyelid. The main outcome measure was the recurrence rate. None of the patients with primary nodular BCC suffered recurrence. The recurrence rate for primary morphoeaform BCC following complete excision is 3.8%. In total, 8.1% of patients had several lesions simultaneously whereas 7.8% patients had BCC in multiple locations subsequently (metachronous). Three patients who had previously recurrent BCC (rBCC) treated elsewhere or not using this method had orbital/lacrimal drainage system involvement requiring exenteration. CONCLUSION: We recommend that patients with a single, completely excised primary solid or nodular BCC can be discharged after one 6-monthly review, although they should be instructed to monitor for the development of further lesions. The incidence of recurrence for primary morphoeaform BCC is 3.8% and for rBCC is 3.6% over 5 years and these patients should stay under review for this period.


Assuntos
Carcinoma Basocelular/epidemiologia , Neoplasias Palpebrais/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/cirurgia , Estudos de Coortes , Neoplasias Palpebrais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Neoplasias Cutâneas/cirurgia , Inquéritos e Questionários , Reino Unido/epidemiologia
10.
Br J Dermatol ; 161(2): 364-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19438459

RESUMO

BACKGROUND: The relationships between so-called spitzoid tumours have proven difficult to understand. OBJECTIVES: To address three questions: does spitzoid tumour morphological similarity reflect molecular similarity? Does Spitz naevus progress into spitzoid melanoma? Are ambiguous spitzoid tumours genuine entities? METHODS: BRAF, NRAS and HRAS mutations were analysed using single-strand conformational polymorphism analysis and sequencing. RESULTS: Both Spitz naevi and spitzoid melanoma had a lower combined BRAF and NRAS mutation frequency compared with common acquired naevi (P = 0.0001) and common forms of melanoma (P = 0.0072), respectively. To look for evidence of progression from Spitz naevi to spitzoid melanoma, HRAS was analysed in 21 spitzoid melanomas, with no mutations identified. The binomial probability of this was 0.03 based on an assumption of a 15% mutation frequency in Spitz naevi with unbiased progression. Under these assumptions, HRAS mutations must be rare/absent in spitzoid melanoma. Thus, Spitz naevi seem unlikely to progress into spitzoid melanoma, implying that ambiguous spitzoid tumours cannot be intermediate degrees of progression. In addition, the data suggest that HRAS mutation is a potential marker of benign behaviour, in support of which none of three HRAS mutant spitzoid cases metastasized. CONCLUSIONS: First, the morphological similarity of spitzoid tumours reflects an underlying molecular similarity, namely a relative lack of dependence on BRAF/NRAS mutations. Second, Spitz naevi do not appear to progress into spitzoid melanoma, and consequently ambiguous spitzoid tumours are likely to be unclassifiable Spitz naevi or spitzoid melanoma rather than genuine entities. Third, HRAS mutation may be a marker of Spitz naevus, raising the possibility that other molecular markers for discriminating Spitz naevi from spitzoid melanoma can be discovered.


Assuntos
Melanoma/genética , Mutação/genética , Nevo de Células Epitelioides e Fusiformes/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Cutâneas/genética , Adulto , Análise Mutacional de DNA , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Melanoma/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Polimorfismo Conformacional de Fita Simples , Neoplasias Cutâneas/patologia
14.
Rev Palaeobot Palynol ; 113(4): 287-297, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11179718

RESUMO

The homoxylous fossil woods occurring in the Gondwanan continents of South America, Australia, Africa, India and Antarctica during the Jurassic and Early Cretaceous period are considered here. Original descriptions of the genera and wherever possible, the type material, have been consulted. Applying the rules of the International Code of Botanical Nomenclature, the generic names of the homoxylous woods have been revised from a nomenclatural point of view. According to this review, out of 31 generic names used for woods from the given time interval and area, 6 are illegitimate later nomenclatural synonyms, 1 is a later homonym, and 5 can be considered as taxonomical synonyms. Moreover, 9 genera have been used erroneously. We propose one new generic name (Protaxodioxylon n. gen.) and elsewhere we will propose for conservation, with a conserved type one of the illegitimate names and one of the taxonomic synonyms. As a result, we consider that there are only eighteen generic names correctly quoted for the Jurassic-Early Cretaceous of Gondwana, and we provide a taxonomic key for the corresponding genera. This revision is the first step in systematically comparing northern and southern hemisphere woods.

18.
Arch Dis Child ; 81(5): 442-3, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10519723

RESUMO

A 5 year old boy developed severe weakness after receiving vincristine for treatment of acute lymphoblastic leukaemia. Although weakness improved after the discontinuation of vincristine, other symptoms suggestive of a neuropathy persisted. Neurophysiological and genetic analysis at age 8 years indicated that vincristine had induced symptoms of a hereditary sensory motor neuropathy type 1A, which had previously been asymptomatic; his genetically affected mother was also asymptomatic.


Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Doença de Charcot-Marie-Tooth/induzido quimicamente , Vincristina/efeitos adversos , Doença de Charcot-Marie-Tooth/genética , Pré-Escolar , Seguimentos , Humanos , Masculino
19.
J Nurs Manag ; 5(6): 333-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9423404

RESUMO

The introduction of market forces into health care delivery systems has had a number of important influences on the roles nurses perform. There have been increasing efforts to find alternative and more cost-effective ways of delivering care. One facet of this situation has been the examination of the roles and responsibilities of registered nurses (RNs) with the view of exploring different ways of using professional skills and determining if RN services are always required. One result of this has been the increased use of unlicensed personnel. The substitution of professional nursing staff by unlicensed personnel has become a major concern for practitioner, manager and client alike. This paper reviews some of the concepts of economic substitution as well as the assumptions advanced for the use of unlicensed personnel in clinical areas as a substitute for nursing services. While there has been increased use of unlicensed staff, the evaluation of clinical outcomes has been poor. This paper reviews primarily the hospital-based evidence about the impact of using unlicensed personnel in practice, and suggests there are methodological problems with the research published to date. Findings suggest that substitute service providers generally 'do no harm'. By contrast, evidence is presented indicating the major contributions nurses make to client care when adopting advanced practice roles (acting as a substitute for other professionals).


Assuntos
Assistentes de Enfermagem/organização & administração , Cuidados de Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Humanos , Avaliação de Resultados em Cuidados de Saúde , Reino Unido
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