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Mental imagery may represent a weaker form of perception and, thus, mental images may be more ambiguous than visual percepts. If correct, the acquisition of fear would be less specific for imagined fears in comparison to perceptual fears, perhaps facilitating broader fear generalization. To test this idea, a two-day differential fear conditioning experiment (N = 98) was conducted. On day one, two groups of participants underwent differential fear conditioning such that a specific Gabor patch orientation (CS+) was paired with mild shocks (US) while a second Gabor patch of orthogonal orientation (CS-) was never paired with shock. Critically, one group imagined the Gabor patches and the other group was visually presented the Gabor patches. Next, both groups were presented visual Gabor patches of similar orientations (GCS) to the CS+. On day two, to assess the persistence of imagined fear, participants returned to the lab and were tested on the GCS devoid of shock. For day one, in contrast to our primary hypothesis, both self-report and skin conductance response measures did not show a significant interaction between the GCS and groups. On day two, both measures demonstrated a persistence of imagined fear, without US delivery. Taken together, rather than demonstrating an overgeneralization effect, the results from this study suggest that imagery-based fear conditioning generalizes to a similar extent as perceptually acquired fear conditioning. Further, the persistence of imagery-based fear may have unique extinction qualities in comparison to perceptual-based fear.
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Condicionamiento Clásico , Miedo , Respuesta Galvánica de la Piel , Generalización Psicológica , Imaginación , Humanos , Miedo/fisiología , Imaginación/fisiología , Masculino , Femenino , Adulto Joven , Generalización Psicológica/fisiología , Respuesta Galvánica de la Piel/fisiología , Condicionamiento Clásico/fisiología , Adulto , AdolescenteRESUMEN
INTRODUCTION: To reduce the risks involved with ionising radiation exposure, typical values (TVs) and diagnostic reference levels (DRLs) have been established to help keep radiation doses 'as low as reasonably practicable. TVs/DRLs provide standardised radiation dose metrics that can be used for comparative purposes. However, for paediatrics, such values should consider the size of the child instead of their age. This study aimed to establish and compare paediatric TVs for chest, abdomen and pelvis radiography. METHODS: Study methods followed processes for establishing paediatric DRLs as outlined by the Health Information and Quality Authority (HIQA). Kerma-area product (KAP) values, excluding rejected images, were retrospectively acquired from the study institution's Picture Archiving and Communications System (PACS). Paediatric patients were categorised into the following weight-based groupings (5 to <15 kg, 15 to <30 kg, 30 to <50 kg, 50 to 80 kg) and stratified based on the examination that was performed (chest, abdomen, and pelvis), and where it was performed (the different X-ray rooms). Anonymised data were inputted into Microsoft Excel for analysis. Median and 3rd quartile KAP values were reported together with graphical illustrations. RESULTS: Data from 407 X-ray examinations were analysed. For the previously identified weight categories (5 to <15 kg, 15 to <30 kg, 30 to <50 kg, 50 to 80 kg), TVs for the chest were 0.10, 0.19, 0.37 and 0.53 dGy.cm2, respectively. For the abdomen 0.39, 1.04, 3.51 and 4.05 dGy.cm2 and for the pelvis 0.43, 0.87, 3.50 and 7.58 dGy.cm2. Between X-ray rooms TVs varied against the institutional TVs by -60 to 119 % (chest), -50 to 103 % (abdomen) and -14 and 24 %% (pelvis). CONCLUSION: TVs in this study follow established trends with patient weight and examination type and are comparable with published literature. Variations do exist between individual examination rooms and reasons are multifactorial. Given that age and size do not perfectly correlate further work should be undertaken around weight-based TVs/DRLs in the paediatric setting.
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The Lemon shark Negaprion brevirostris is an important species experiencing conservation issues that is in need of genomic resources. Herein, we conducted a genome survey sequencing in N. brevirostris and determined genome size, explored repetitive elements, assembled and annotated the 45S rRNA DNA operon, and assembled and described in detail the mitochondrial genome. Lastly, the phylogenetic position of N. brevirostris in the family Carcharhinidae was examined using translated protein coding genes. The estimated haploid genome size ranged between 2.29 and 2.58 Gbp using a k-mer analysis, which is slightly below the genome size estimated for other sharks belonging to the family Carcharhinidae. Using a k-mer analysis, approx. 64-71 % of the genome of N. brevirostris was composed of repetitive elements. A relatively large proportion of the 'repeatome' could not be annotated. Taking into account only annotated repetitive elements, Class I - Long Interspersed Nuclear Element (LINE) were the most abundant repetitive elements followed by Class I - Penelope and Satellite DNA. The nuclear ribosomal operon was fully assembled. The AT-rich complete mitochondrial genome was 16,703 bp long and encoded 13 protein coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes. Negaprion brevirostris is closely related to the genera Carcharhinus, Glyphis and Lamiopsis in the family Carcharinidae. This new genomic resources will aid with the development of conservation plans for this large coastal shark.
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Genoma Mitocondrial , Tiburones , Animales , Tamaño del Genoma , Filogenia , ADN , Tiburones/genéticaRESUMEN
OBJECTIVES: To report clinical outcomes of relapsed oropharyngeal squamous cell carcinoma (OPSCC) after definitive intensity-modulated (chemo)radiotherapy [(C)RT]. MATERIALS AND METHODS: Data for all relapsed patients treated for OPSCC with definitive (C)RT between 2010 and 2016 were collected. Primary end-point was post-failure survival (PFS). RESULTS: Overall, 273 OPSCC patients completed definitive (C)RT. Of these, 42 cases (n = 26 human papilloma virus (HPV)-negative; n = 16 HPV-positive) had relapsed (n = 23 persistent disease; n = 19 recurrent disease) and were included in the final analysis. Two-year PFS for the entire population was 30.6%; 20.5% for HPV-negative and 43.8% for HPV-positive patients. Salvage curative surgery was associated with a significantly higher 2 years PFS rate (56.2%) compared with palliative treatment (22.9%) and best supportive care (0%) (p < 0.001). A positive trend in 2 years PFS was recorded in the early complete response cases (49.5%) versus patients who did not achieve a complete response within 3 months of the end of (C)RT (23.0%) (p = 0.11). CONCLUSION: A higher PFS rate is achieved when relapsed OPSCC cases are treated with salvage curative intent. HPV-positive disease and early complete response within 3 months from the end of (C)RT may be related to better PFS.
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Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Infecciones por Papillomavirus/complicaciones , Neoplasias Orofaríngeas/tratamiento farmacológico , Neoplasias Orofaríngeas/radioterapia , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias de la Boca/complicaciones , Virus del Papiloma Humano , Enfermedad Crónica , Neoplasias de Cabeza y Cuello/complicaciones , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Awake fibreoptic intubation is a complex advanced airway technique used by anaesthesiologists in the management of a difficult airway. The time to setup this important procedure can be significant which may dissuade its use by some providers. In our institution, the awake intubation setup process was highly variable and error prone. METHODS: We deployed Lean methods to improve the efficiency and accuracy of the awake fibreoptic intubation setup process. A 2-day improvement event with a multidisciplinary team addressed the setup process, tested solutions and created standard work documents. Twenty awake fibreoptic intubation simulations were conducted before and after the intervention to quantify gains in setup efficiency and error reduction. RESULTS: Variability in the setup process, including clinical locations visited, was reduced through creating a standardised process. The average time to for an awake fibreoptic intubation setup was reduced by approximately 50%, from 23 min to 11 min (p<0.001). In addition, awake fibreoptic intubation equipment set out without error increased in the postintervention simulations from 59% to 85% (p=0.003). CONCLUSION: Using Lean tools, we were able to make the setup of awake fibreoptic intubation not only more efficient, but also more accurate. A similar methodological approach may have value for other complex anaesthesia procedures.
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Intubación Intratraqueal , Vigilia , Tecnología de Fibra Óptica , HumanosRESUMEN
The incidence of metastases following neck dissection in the apparent lymph node negative neck in oral cancer is between 7% and 33%; early resection of cervical metastases may well increase survival. Modern imaging techniques can reduce the yield of previously undiagnosed metastatic nodes in elective neck dissection (END). An audit of 112 consecutive cases was conducted to determine the proportion of undiagnosed nodal metastases, after END. There were neck metastases in 10 cases (9%), which were mainly (but not all) micrometastic. The 20% likelihood of nodal metastases was only apparent in primary tumours greater than 6 mm thick. The length of inpatient stay was increased from 3.7 to 16.5 days with free vascularised transfer. There were complications including cranial nerve damage. There were two peri-operative deaths. No ipsilateral neck failures occurred, median follow up was 937 days. To reduce unnecessary END, resection can be undertaken as a prior procedure, subsequently only carrying out END on tumours greater than 6 mm, or with unfavourable tumour characteristics.
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Carcinoma de Células Escamosas , Neoplasias de la Boca , Humanos , Ganglios Linfáticos , Metástasis Linfática , Cuello , Disección del Cuello , Estadificación de Neoplasias , Estudios RetrospectivosRESUMEN
Head and neck squamous cell carcinoma (HNSCC) has a significant impact on patients' quality of life and treatment can be associated with severe morbidity. Following completion of treatment, patients are followed up in order to detect potentially salvageable recurrences and to manage long-term toxicities. In recent years, a growing interest has been given to risk stratified follow-up interventions to prevent and detect recurrences and manage treatment toxicities in other tumour sites as well as to transfer some of that care to community services. We review the literature for HNSCC and propose a risk stratified follow up protocol to address these issues and assist clinicians in decision making. A shift in patterns of care is suggested in order to provide a basis to improve care for HNSCC patients after complete response to primary treatment.
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Neoplasias de Cabeza y Cuello , Carcinoma de Células Escamosas de Cabeza y Cuello , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/terapia , Humanos , Recurrencia Local de Neoplasia/terapia , Calidad de Vida , Recurrencia , Carcinoma de Células Escamosas de Cabeza y Cuello/terapiaRESUMEN
PURPOSE: To assess TNM 8 staging in discriminating overall survival (OS) amongst patients with locally advanced oral cavity squamous cell carcinoma (OCSCC) treated with surgery and post-operative radiotherapy (PORT), compared to TNM 7. MATERIAL AND METHODS: Data from OCSCC patients treated with surgery and PORT between January 2010 and December 2018 were reviewed. Demographics, tumour characteristics and treatment response data were collected, and patients staged according to both TNM 7 and TNM 8. OS and disease free survival (DFS) were estimated using the Kaplan Meier method. Univariate and multivariable analyses were conducted for factors affecting OS, DFS and early disease recurrence within 12 months. RESULTS: Overall 172 patients were analyzed. Median follow up was 32 months for all patients and 48 months for surviving patients. TNM 8 staging demonstrated significant stratification of OS and DFS amongst the entire cohort, whereas TNM 7 staging did not. On multivariable analysis, TNM 8 stage, performance status (PS) and a positive surgical margin were prognostic for OS. Looking at disease recurrence within 12 months, TNM 8 stage IVB, presence of lymphovascular invasion (LVSI), younger age and lesser smoking history were predictive factors on multivariable analysis. CONCLUSION: TNM 8 is a good development of its predecessor in terms of predicting survival for patients with locally advanced OCSCC. We have also identified younger age (<60 years) and a smoking history of <10 pack years as risk factors for early disease recurrence, potentially representing a separate biological cohort within OCSCC patients.
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Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Persona de Mediana Edad , Neoplasias de la Boca/patología , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/cirugía , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
OBJECTIVES: To analyze clinical features, dosimetric parameters, and outcomes of osteoradionecrosis (ORN). STUDY DESIGN: Thirty-six patients with ORN who had been previously treated with radiotherapy (RT) were retrospectively identified between January 2009 and April 2014. ORN volumes were contoured on planning computed tomography (CT) scans. Near maximum dose (D2%), minimum dose (Dmin), mean dose (Dmean), and percentage of bone volume receiving 50 Gy (V50) were examined. Clinical and dosimetric variables were considered to compare ORN resolution versus ORN persistence. RESULTS: Median interval time from end of RT to development of ORN was 6 months. Of the ORN cases, 61% were located in the mandible. Dmean to affected bone was 57.6 Gy, and 44% had a D2% 65 Gy or greater. Smoking was associated with ORN persistence on univariate analysis, but no factors were found to impact ORN resolution or progression on logistic regression. CONCLUSIONS: Prevention strategies for ORN development should be prioritized. Dose-volume parameters could have a role in preventing ORN.
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Neoplasias de Cabeza y Cuello/radioterapia , Osteorradionecrosis/diagnóstico por imagen , Osteorradionecrosis/etiología , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Dimensión del Dolor , Radiometría , Dosificación Radioterapéutica , Estudios Retrospectivos , Factores de RiesgoRESUMEN
PURPOSE: To evaluate the use of (18)F-FDG PET/CT as the principal investigation to assess tumour response, to determine the need for further surgery and to guide follow-up following radical chemoradiotherapy for stage III/IV oropharyngeal squamous cell carcinoma (OPSCC). METHODS: A retrospective analysis was undertaken in 146 patients treated at our centre with radical chemoradiotherapy for OPSCC and who had a PET/CT scan to assess response. According to the PET/CT findings, patients were divided into four groups and recommendations: (1) complete metabolic response (enter clinical follow-up); (2) low-level uptake only (follow-up PET/CT scan in 12 weeks); (3) residual uptake suspicious for residual disease (further investigation with or without neck dissection); and (4) new diagnosis of distant metastatic disease (palliative treatment options). RESULTS: The initial PET/CT scan was performed at a median of 12.4 weeks (range 4.3 - 21.7 weeks) following treatment. Overall sensitivity and specificity rates were 92.0 % (74.0 - 99.0 %) and 85 % (77.5 - 90.9 %). Of the 146 patients, 90 (62 %) had a complete response and had estimated 3-year overall and disease-free survival rates of 91.9 % (85.6 - 98.2 %) and 85.6 % (78.0 - 93.2 %), respectively, 17 (12 %) had residual low-level uptake only (with two having confirmed residual disease on subsequent PET/CT, both surgically salvaged), 30 (21 %) had suspicious residual uptake (12 proceeded to neck dissection; true positive rate at surgery 33 %). HPV-positive patients with reassuring PET/CT findings had an estimated 3-year progression-free survival rate of 91.7 % (85.2 - 98.2 %), compared with 66.2 % (41.5 - 90.9 %) of HPV-negative patients. CONCLUSION: A strategy of using PET/CT results alongside clinical examination to help select patients for salvage surgery appears successful. Despite a complete response on the 12-week PET/CT scan, HPV-negative patients have a significant risk of disease relapse in the following 2 years and further studies to assess whether surveillance imaging in this group could improve outcomes are warranted.
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Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Fluorodesoxiglucosa F18 , Neoplasias Orofaríngeas/diagnóstico por imagen , Neoplasias Orofaríngeas/terapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , Anciano , Anciano de 80 o más Años , Transporte Biológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Femenino , Fluorodesoxiglucosa F18/metabolismo , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias Orofaríngeas/metabolismo , Neoplasias Orofaríngeas/patología , Estudios Retrospectivos , Medición de Riesgo , Resultado del TratamientoRESUMEN
We develop a stochastic, agent-based model to study how genetic traits and experiential changes in the state of agents and available resources influence individuals' foraging and movement behaviors. These behaviors are manifest as decisions on when to stay and exploit a current resource patch or move to a particular neighboring patch, based on information of the resource qualities of the patches and the anticipated level of intraspecific competition within patches. We use a genetic algorithm approach and an individual's biomass as a fitness surrogate to explore the foraging strategy diversity of evolving guilds under clonal versus hermaphroditic sexual reproduction. We first present the resource exploitation processes, movement on cellular arrays, and genetic algorithm components of the model. We then discuss their implementation on the Nova software platform. This platform seamlessly combines the dynamical systems modeling of consumer-resource interactions with agent-based modeling of individuals moving over a landscapes, using an architecture that lays transparent the following four hierarchical simulation levels: 1.) within-patch consumer-resource dynamics, 2.) within-generation movement and competition mitigation processes, 3.) across-generation evolutionary processes, and 4.) multiple runs to generate the statistics needed for comparative analyses. The focus of our analysis is on the question of how the biomass production efficiency and the diversity of guilds of foraging strategy types, exploiting resources over a patchy landscape, evolve under clonal versus random hermaphroditic sexual reproduction. Our results indicate greater biomass production efficiency under clonal reproduction only at higher population densities, and demonstrate that polymorphisms evolve and are maintained under random mating systems. The latter result questions the notion that some type of associative mating structure is needed to maintain genetic polymorphisms among individuals exploiting a common patchy resource on an otherwise spatially homogeneous landscape.
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Evolución Clonal , Animales , Ecosistema , Dinámica Poblacional , Programas InformáticosRESUMEN
Osteoradionecrosis (ORN) is potentially a debilitating and serious consequence of radiotherapy to the head and neck. Although it is often defined as an area of exposed bone that does not heal, it can also exist without breaching the mucosa or the skin. Currently, 3 classifications of ORN are in use, but they depend on the use of hyperbaric oxygen or are too complicated to be used as a simple aide-mémoire, and include features that do not necessarily influence its clinical management. We propose a new classification to cover these shortcomings and to take into account the increasingly widespread use of antifibrotic medical treatment. We classified a series of 85 patients with varying severities of ORN into 4 groups. An analysis of the outcomes of the series showed that the classification staged the severity of the condition simply and that the stage was relevant to both treatment and outcome. The new classification was therefore verified by the series presented.
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Osteorradionecrosis/clasificación , Antioxidantes/uso terapéutico , Depuradores de Radicales Libres/uso terapéutico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Oxigenoterapia Hiperbárica , Osteorradionecrosis/terapia , Pentoxifilina/uso terapéutico , Colgajos Quirúrgicos/trasplante , Vitamina E/uso terapéuticoRESUMEN
High morbidity has been reported for free vascularised reconstruction for osteoradionecrosis (ORN) and there are no apparent risk factors. A single nucleotide polymorphism in the transforming growth factor beta 1 gene (TGF-ß1) has been implicated in the cause of ORN and may also predict these complications. We studied a series of 30 consecutive patients who had had reconstruction for severe ORN with free tissue transfer in relation to their outcomes and complications for a number of risk factors including TFG-ß1 genotype, age, sex, comorbidities, site and stage of tumour, type of initial operation, and dose of radiotherapy or chemoradiotherapy. Two patients died and 2 flaps failed. Using the Clavien-Dindo classification, 16 patients developed grade III complications and 6 grade II. Median (IQR) duration of inpatient stay was 19.5 (12-25) days and the median (IQR) duration of outpatient treatment was 6 (4-11) weeks. No specific risk factors for postoperative complications were identified. In view of the severity and unpredictability of the complications, careful preoperative counselling of patients is essential.
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Enfermedades Maxilomandibulares/cirugía , Osteorradionecrosis/cirugía , Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias , Factores de Edad , Anciano , Atención Ambulatoria , Quimioradioterapia , Femenino , Predicción , Colgajos Tisulares Libres/irrigación sanguínea , Colgajos Tisulares Libres/trasplante , Genotipo , Hospitalización , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/cirugía , Estadificación de Neoplasias , Polimorfismo de Nucleótido Simple/genética , Dosificación Radioterapéutica , Reoperación , Factores de Riesgo , Factores Sexuales , Timina , Factor de Crecimiento Transformador beta1/genética , Resultado del TratamientoRESUMEN
OBJECTIVES: Trismus frequently occurs as a consequence of radiotherapy or chemo-radiotherapy to the head and neck, with a loss of function that can reduce the overall quality of life. Radiation can trigger an intense fibrosis within the masticatory muscles and transforming growth factor beta 1 (TGF ß1) is involved in this process. As in other tissues the degree of fibrosis may be related to a single nucleotide polymorphism; C-T at position -509 in the TGF ß1 gene. MATERIALS AND METHODS: Trismus was measured in 62 patients before and after radiotherapy or chemoradiotherapy, blood was taken for DNA extraction, and genotype analysis of the TGF ß1 gene. Trismus was analysed against, patient age, sex, tumour site and stage, radiotherapy, and chemotherapy. RESULTS AND CONCLUSIONS: After radiotherapy or chemo-radiotherapy the reduction in mouth opening was shown to be significantly related to the presence of the T allele (p<0.001), with patients homozygous the most likely to be severely affected. No other patient, tumour or treatment factors were significant. Hence the TGF ß1 genotype is likely to be an important predictor of the degree of post radiotherapy or chemo-radiotherapy trismus.
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Neoplasias de Cabeza y Cuello/radioterapia , Radioterapia/efectos adversos , Trismo/etiología , Adulto , Anciano , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/radioterapia , Femenino , Genotipo , Neoplasias de Cabeza y Cuello/genética , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Advances in GPS technology have created both opportunities in ecology as well as a need for analytical tools that can deal with the growing volume of data and ancillary variables associated with each location. RESULTS: We present T-LoCoH, a home range construction algorithm that incorporates time into the construction and aggregation of local kernels. Time is integrated with Euclidean space using an adaptive scaling of the individual's characteristic velocity, enabling the construction of utilization distributions that capture temporal partitions of space as well as contours that differentiate internal space based on movement phase and time-use metrics. We test T-LoCoH against a simulated dataset and provide illustrative examples from a GPS dataset from springbok in Namibia. CONCLUSIONS: The incorporation of time into home range construction expands the concept of utilization distributions beyond the traditional density gradient to spatial models of movement and time, opening the door to new applications in movement ecology.
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Since the advent of community-based natural resource management (CBNRM) in the mid-1980s, scholars and practitioners have sought to explain the uneven performance of CBNRM programs. Most CBNRM assessments examine the underlying principles of community-based conservation, the local social and ecological contexts, and connections with larger political and historical patterns. In this article, I argue that analysis of the potential and pitfalls of CBNRM also requires an understanding of the institutional history and internal dynamics of projects that implement CBNRM reforms. Drawing upon theory and methods from development ethnography and public policy, I examine the rise and fall of CONASA, a second-generation CBNRM project in Zambia that operated from 2001 to 2004. CONASA was constituted from a merger of organizations and discourses to provide continuity with previous projects. Its ambitious suite of activities included support for household livelihoods, community-based resource management, policy analysis, advocacy, and conservation enterprises at local, national, and transboundary levels. While individual activities were largely successful, CONASA's hybrid origins and logframe-centric management created fissures between its holistic design and operational logics, and hindered its ability to develop a broader narrative and maintain key alliances. This case study illustrates the importance of understanding the interplay between project design and operational context to fully appreciate the possibilities and limitations of project-mode conservation.
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Conservación de los Recursos Naturales , ZambiaRESUMEN
BACKGROUND: Sentinel lymph node biopsy (SLNB) is an established technique in breast and melanoma surgery and is gaining acceptance in the management of oral cavity squamous cell carcinoma. We report a single institution's experience of SLNB between 2006 and 2010. METHODS: Prospective consecutive cohort study of 59 patients recruited between 2006 and 2010. All patients underwent SLNB with preoperative lymphoscintigraphy, intraoperative blue dye, and handheld gamma probe. Sentinel nodes were evaluated with step-serial sectioning and immunohistochemistry. Endpoints included: overall survival (OS), disease-specific survival (DSS), local recurrence-free survival (LRFS), and regional recurrence-free survival (RRFS). RESULTS: A total of 59 patients (36 male and 23 female) were operated on. Of these, 42 patients (71%) were pT1 and 17 patients (29%) were pT2. In two patients the sentinel node was not identified and proceeded to elective neck dissection. A total of 150 nodes were harvested from the remaining 57 patients of which 21 nodes were positive in 17 patients; three patients had positive contralateral nodes. The 2-year OS, DSS, LRFS, and RRFS for the SLNB negative patients were 97.5, 100, 95.8, and 95.8% and for the SLNB positive patients 68.2, 81.8, 83.9, and 100% respectively. Only OS and DSS approached statistical significance with P values of 0.07 and 0.06. CONCLUSIONS: SLNB is a safe and accurate diagnostic technique for staging the neck with a negative predictive value in our series of 97.5%. Furthermore, in our series three patients (5%) had positive contralateral neck drainage that would have been missed by conventional ipsilateral neck dissection.
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Carcinoma de Células Escamosas/secundario , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Neoplasias de la Boca/patología , Recurrencia Local de Neoplasia/patología , Biopsia del Ganglio Linfático Centinela , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/cirugía , Disección del Cuello , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Radioterapia AdyuvanteRESUMEN
PURPOSE: We performed a case-control study to establish whether the development of osteoradionecrosis (ORN) was related to a variant allele substituting T for C at -509 of the transforming growth factor-ß1 gene (TGF-ß1). PATIENTS AND METHODS: A total of 140 patients, 39 with and 101 without ORN, who underwent radiotherapy for head-and-neck cancer with a minimum of 2 years follow-up, were studied. None of the patients had clinical evidence of recurrence at this time. DNA extracted from blood was genotyped for the -509 C-T variant allele of the TGF-ß1 gene. RESULTS: There were no significant differences in patient, cancer treatment, or tumor characteristics between the two groups. Of the 39 patients who developed ORN, 9 were homozygous for the common CC allele, 19 were heterozygous, and 11 were homozygous for the rare TT genotype. Of the 101 patients without ORN, the distribution was 56 (CC), 33 (CT), and 12 (TT). The difference in distribution was significant, giving an increased risk of ORN of 5.7 (95% CI, 1.7-19.2) for homozygote TT patients (p = 0.001) and 3.6 (95% CI, 1.3-10.0) for heterozygotes (p = 0.004) when compared with patients with the CC genotype. Postradiotherapy dentoalveolar surgery preceding the development of ORN was associated with the CC genotype (p = 0.02). CONCLUSIONS: Our findings support the postulate that the development of ORN is related to the presence of the T variant allele at -509 within the TGF-ß1 gene.
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Alelos , Neoplasias de Cabeza y Cuello/radioterapia , Osteorradionecrosis/genética , Factor de Crecimiento Transformador beta1/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Genotipo , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Osteorradionecrosis/metabolismo , Estudios Retrospectivos , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
BACKGROUND: Bone-containing vascularized grafts have been used successfully to reconstruct post-cancer surgical defects. Dental implants can be placed in these bone-containing grafts to allow implant-supported prosthodontic reconstruction of these patients. PURPOSE: The aim of this study was to evaluate the survival of dental implants used in the rehabilitation of subjects treated with bone-containing vascularized grafts to compare usability of implants placed at the time of reconstruction and after healing. MATERIALS AND METHODS: A cross-sectional study was undertaken to examine survival rates of implants placed in vascularized bone-containing grafts either immediately at the time of surgical reconstruction or after 3 months healing. Other factors such as graft type, whether radiation therapy was given, and implant type were recorded. RESULTS: A total of 41 patients had 145 implants placed in 47 vascularized bone-containing flaps. Increased failure rate of implants was seen in immediately placed implants. There was also a significant increase in the number of osseointegrated implants that were prosthodontically unusable or sub-optimally placed in the immediate placement group. Radiation therapy was associated with a significant increase in failure rate. Modern implant surfaces appeared to perform better than machined/turned surfaces. Graft donor site did not influence implant survival. CONCLUSION: This study demonstrated the difficulties encountered with immediate placement of dental implants at the time of post-cancer reconstructive surgery.
Asunto(s)
Trasplante Óseo/patología , Implantación Dental Endoósea/métodos , Implantes Dentales , Neoplasias de Cabeza y Cuello/cirugía , Procedimientos de Cirugía Plástica/métodos , Estudios Transversales , Implantes Dentales/clasificación , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Fracaso de la Restauración Dental , Operatoria Dental , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Mandíbula/cirugía , Maxilar/cirugía , Oseointegración/efectos de la radiación , Radioterapia Adyuvante , Propiedades de Superficie , Cirugía Bucal , Análisis de Supervivencia , Sitio Donante de Trasplante/patología , Resultado del Tratamiento , Cicatrización de Heridas/fisiologíaRESUMEN
Multidisciplinary meetings (MDMs) are an essential part of the management of head and neck cancer. Practice care guidance set up by the British Association of Head and Neck Oncologists has recommended that MDMs should have appropriate projection equipment for computer-generated images so that all members of group have access to the same information. The aim of this paper is to review our experience with the integrated visual presentation of head and neck oncology patients and to demonstrate its advantages over conventional approaches. Digital photographs are taken of patients and of their index tumour at presentation or at the time of diagnostic endoscopy. All relevant pre-treatment digitised images from tumour sites and radiological images and histological slides are incorporated into a single presentation using Microsoft PowerPoint software. During the past 2 years, on-line radiological scans have also become accessible for the meeting to aid treatment planning. Subsequently, all peri-operative pictures and post-surgical macroscopic and microscopic histopathological images are added to each patient's presentation, which is then hyperlinked into the agenda. The Guy's and St Thomas' Head and Neck Cancer Centre treats over 400 patients a year, and since 2002, all new cancer diagnoses have been discussed in the weekly MDM as described above. A total of 1,638 presentations have been incorporated in a centralized database that is updated in the event of recurrence, further primary tumours or other clinical developments. Satisfactory documentation and staging of head and neck tumours must include a verbal description, accurate measurement, diagrammatic representation, photographic recording and appropriate radiological imaging. Integrated presentation at MDM collates all relevant findings for clinical management decisions on patients with head and neck cancer. This approach is also an extremely valuable adjunct to long-term clinical monitoring.