RESUMEN

Among-individual variation in predator traits is ubiquitous in nature. However, variation among populations in this trait variation has been seldom considered in trophic dynamics. This has left unexplored (a) to what degree does among-individual variation in predator traits regulate prey populations and (b) to what degree do these effects vary spatially. We address these questions by examining how predator among-individual variation in functional traits shapes communities across habitats of varying structural complexity, in field conditions. We manipulated Chinese mantis (Tenodera sinensis) density (six or twelve individuals) and behavioral trait variability (activity level by movement on an open field) in experimental patches of old fields with varying habitat complexity (density of plant material). Then, we quantified their impacts on lower trophic levels, specifically prey (arthropods > 4 mm) and plant biomass. Predator behavioral variability only altered prey biomass in structurally complex plots, and this effect depended on mantis density. In the plots with the highest habitat complexity and mantis density, behaviorally variable groups decreased prey biomass by 40.3%. In complex plots with low mantis densities, low levels of behavioral variability decreased prey biomass by 32.2%. Behavioral variability and low habitat complexity also changed prey community composition, namely by increasing ant biomass by 881%. Our results demonstrate that among-individual trait variation can shape species-rich prey communities. Moreover, these effects depend on both predator density and habitat complexity. Incorporating this important facet of ecological diversity revealed normally unnoticed effects of functional traits on the structure and function of food webs.

Asunto(s)

Ecosistema , Cadena Alimentaria , Conducta Predatoria , Animales , Biomasa , Dinámica Poblacional

RESUMEN

BACKGROUND: Cervical smear cytology and colposcopic biopsy histology are prone to error at both collection and interpretation stages, leading to a large number of discordant cases. AIMS: Investigation of five-year outcomes for women who have cervical cytology that is discordant and higher grade than histology results. MATERIALS AND METHODS: A retrospective cohort study was carried out for 111 women with cervical cytology discordant and higher grade than histology, after cytopathological review, over a three-year period. Five-year follow-up data were reviewed to identify the highest level of pathology seen within five years from the discordance. RESULTS: Women with atypical squamous cells with possible high-grade change (ASC-H) cytology and negative biopsy (n = 28) had a 46% chance of high-grade histological disease within 5 years; with cervical intraepithelial neoplasia grade 1 (CIN1) histology (n = 20), this was reduced to 30%. With high-grade cytology and negative histology (n = 23), 48% had high-grade disease within five years, including one case of invasive disease; with CIN1 histology 50% had high-grade disease within five years. CONCLUSIONS: This study demonstrates a 30-50% chance of high-grade disease within five years, in the setting of ASC-H or high-grade cytology with a negative or low-grade colposcopic biopsy. This highlights that in the setting of cytology and histology discordance, at least one of the tests indicating high-grade pathology warrants the need for treatment or close ongoing surveillance.

Asunto(s)

Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Colposcopía , Femenino , Estudios de Seguimiento , Humanos , Embarazo , Estudios Retrospectivos , Frotis Vaginal

RESUMEN

Oral infection with human papillomavirus (HPV) is likely to underpin the rapidly rising incidence of oropharyngeal squamous cell carcinoma; however, there are few data describing the natural history of oral HPV infection. We recruited 704 participants aged 20 to 70 years from worksites, universities and primary care practices in Brisbane, Australia. Participants completed questionnaires at baseline, 12 and 24 months and donate four saliva samples at baseline, 6, 12 and 24 months for HPV polymerase chain reaction testing and typing. We estimated the prevalence of oral HPV infection at baseline, incidence of new infections among those HPV-negative at baseline, clearance rate and persistent infections. At baseline, 10.7% of participants had oral HPV infections from 26 different HPV types. Sexual behaviours were associated with oral HPV infection, including more partners for passionate kissing (29 or more; odds ratio [OR] 3.4, 95% confidence interval [CI] 1.5-8.0), and giving and receiving oral sex (16 or more; OR 5.4, 95% CI 1.6-17.7 and OR 5.6, 95% CI 1.6-18.7, respectively). Of 343 participants, HPV-free at baseline and with subsequent saliva samples, 87 (25%) acquired new infections over the 24 months. Sixty-eight of 87 people included in the clearance analysis (78%) cleared their oral HPV infections. Clearance was associated with being a nonsmoker (OR 12.7, 95% CI 1.3-122.8), and no previous diagnosis of a sexually transmitted infection (OR 6.2, 95% CI 2.0-19.9). New oral infections with HPV in this sample were not rare. Although most infections were cleared, clearance was not universal suggesting a reservoir of infection exists that might predispose to oropharyngeal carcinogenesis.

Asunto(s)

Carcinoma de Células Escamosas/diagnóstico , Enfermedades de la Boca/diagnóstico , Neoplasias Orofaríngeas/diagnóstico , Infecciones por Papillomavirus/diagnóstico , Encuestas y Cuestionarios , Adulto , Anciano , Alphapapillomavirus/clasificación , Alphapapillomavirus/fisiología , Australia/epidemiología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/virología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/epidemiología , Enfermedades de la Boca/virología , Neoplasias Orofaríngeas/epidemiología , Neoplasias Orofaríngeas/virología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Prevalencia , Estudios Prospectivos , Saliva/virología , Conducta Sexual/estadística & datos numéricos , Factores de Tiempo , Adulto Joven

RESUMEN

BACKGROUND: For many years, first-line treatment for locally advanced or metastatic soft-tissue sarcoma has been doxorubicin. This study compared gemcitabine and docetaxel versus doxorubicin as first-line treatment for advanced or metastatic soft-tissue sarcoma. METHODS: The GeDDiS trial was a randomised controlled phase 3 trial done in 24 UK hospitals and one Swiss Group for Clinical Cancer Research (SAKK) hospital. Eligible patients had histologically confirmed locally advanced or metastatic soft-tissue sarcoma of Trojani grade 2 or 3, disease progression before enrolment, and no previous chemotherapy for sarcoma or previous doxorubicin for any cancer. Patients were randomly assigned 1:1 to receive six cycles of intravenous doxorubicin 75 mg/m2 on day 1 every 3 weeks, or intravenous gemcitabine 675 mg/m2 on days 1 and 8 and intravenous docetaxel 75 mg/m2 on day 8 every 3 weeks. Treatment was assigned using a minimisation algorithm incorporating a random element. Randomisation was stratified by age (≤18 years vs >18 years) and histological subtype. The primary endpoint was the proportion of patients alive and progression free at 24 weeks in the intention-to-treat population. Adherence to treatment and toxicity were analysed in the safety population, consisting of all patients who received at least one dose of their randomised treatment. The trial was registered with the European Clinical Trials (EudraCT) database (no 2009-014907-29) and with the International Standard Randomised Controlled Trial registry (ISRCTN07742377), and is now closed to patient entry. FINDINGS: Between Dec 3, 2010, and Jan 20, 2014, 257 patients were enrolled and randomly assigned to the two treatment groups (129 to doxorubicin and 128 to gemcitabine and docetaxel). Median follow-up was 22 months (IQR 15·7-29·3). The proportion of patients alive and progression free at 24 weeks did not differ between those who received doxorubicin versus those who received gemcitabine and docetaxel (46·3% [95% CI 37·5-54·6] vs 46·4% [37·5-54·8]); median progression-free survival (23·3 weeks [95% CI 19·6-30·4] vs 23·7 weeks [18·1-20·0]; hazard ratio [HR] for progression-free survival 1·28, 95% CI 0·99-1·65, p=0·06). The most common grade 3 and 4 adverse events were neutropenia (32 [25%] of 128 patients who received doxorubicin and 25 [20%] of 126 patients who received gemcitabine and docetaxel), febrile neutropenia (26 [20%] and 15 [12%]), fatigue (eight [6%] and 17 [14%]), oral mucositis (18 [14%] and two [2%]), and pain (ten [8%] and 13 [10%]). The three most common serious adverse events, representing 111 (39%) of all 285 serious adverse events recorded, were febrile neutropenia (27 [17%] of 155 serious adverse events in patients who received doxorubicin and 15 [12%] of 130 serious adverse events in patients who received gemcitabine and docetaxel, fever (18 [12%] and 19 [15%]), and neutropenia (22 [14%] and ten [8%]). 154 (60%) of 257 patients died in the intention-to-treat population: 74 (57%) of 129 patients in the doxorubicin group and 80 (63%) of 128 in the gemcitabine and docetaxel group. No deaths were related to the treatment, but two deaths were due to a combination of disease progression and treatment. INTERPRETATION: Doxorubicin should remain the standard first-line treatment for most patients with advanced soft-tissue sarcoma. These results provide evidence for clinicians to consider with their patients when selecting first-line treatment for locally advanced or metastatic soft-tissue sarcoma. FUNDING: Cancer Research UK, Sarcoma UK, and Clinical Trial Unit Kantonsspital St Gallen.

Asunto(s)

Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Neoplasias de los Tejidos Blandos/tratamiento farmacológico , Neoplasias de los Tejidos Blandos/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Intervalos de Confianza , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Docetaxel , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Esquema de Medicación , Femenino , Humanos , Infusiones Intravenosas , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Sarcoma/mortalidad , Neoplasias de los Tejidos Blandos/mortalidad , Análisis de Supervivencia , Taxoides/administración & dosificación , Taxoides/efectos adversos , Resultado del Tratamiento , Reino Unido , Gemcitabina

RESUMEN

Subclinical oral human papillomavirus (HPV) infection that persists for decades is likely to precede an HPV-driven squamous cell carcinoma of the head and neck, but little is known about the natural history of oral HPV. We systematically reviewed and abstracted data from nine manuscripts that examined human immunodeficiency virus-negative and cancer-free subjects for oral HPV DNA to determine the pooled baseline prevalence and incidence of newly acquired oral HPV infections, and specifically for HPV-16. We also documented the clearance rate and the median time to clearance, where data existed. Of 3762 individuals, 7.5 % had an oral infection with any HPV type (1.6 % for HPV-16). Meta-regression analysis estimated the 12-month cumulative incidence to be 4.8 % (95 % confidence interval 3.2-7.3 %). The overall oral HPV clearance was reported to be 0-80 % between studies, and the median time to clearance from 6.5 to 18 months. Oral HPV-16 clearance was 43-83 %, and median time to clearance for HPV-16 was 7-22 months. Oral HPV prevalence, incidence and clearance vary considerably between published studies from different geographical regions. Further research is required to identify predictors of persistent oral HPV infection. Measurable baseline prevalence was observed in all studies, as well as non-trivial incidence of newly acquired oral HPV infections and incomplete clearance.

Asunto(s)

Enfermedades de la Boca/epidemiología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Genotipo , Humanos , Incidencia , Enfermedades de la Boca/virología , Papillomaviridae/clasificación , Papillomaviridae/genética , Prevalencia

RESUMEN

OBJECTIVES: Many of the approximately 8000 New Zealand retailers selling tobacco are small stores that tobacco companies have represented as victims of policy measures designed to reduce smoking. Despite this depiction, many retailers experience considerable ambivalence in selling tobacco, a product they know harms their customers. We explored how retailers perceived the proposed introduction of standardised (or 'plain') packaging and their assessment of arguments made by tobacco companies in submissions on proposed standardised packaging legislation. PARTICIPANTS: Using qualitative in-depth interviews, we recruited and interviewed 23 retailers of dairies (small convenience stores), small supermarkets, and service stations. ANALYSES: Data were analysed using a protocol-driven approach; this stance enabled direct analysis of tobacco companies' arguments, particularly those purporting to represent retailers' concerns. RESULTS: Retailers were concerned about the financial implications of standardised packaging and the effects it may have on their ability to provide rapid and efficient customer service. However, few thought standardised packaging would foster illicit trade or spawn further regulation; most placed public health goals ahead of tobacco companies' 'rights', and many supported government intervention to protect population health. CONCLUSIONS: Retailers held ambivalent views on standardised packaging; while they were concerned about short-term effects on their business, they recognised the harm smoking causes. Policymakers and health researchers could collaborate more effectively with retailers by assisting them to create financially viable roles more compatible with public health objectives.

Asunto(s)

Etiquetado de Productos/legislación & jurisprudencia , Etiquetado de Productos/normas , Industria del Tabaco/legislación & jurisprudencia , Productos de Tabaco/economía , Comercio , Humanos , Entrevistas como Asunto , Nueva Zelanda , Investigación Cualitativa , Fumar/economía

RESUMEN

BACKGROUND: Gemcitabine and docetaxel have been shown to be active in pre-treated relapsed leiomyosarcoma. This study investigated the combination as first line treatment in patients with unresectable locally advanced/metastatic leiomyosarcoma. METHODS: Patients received gemcitabine 900 mg/m(2) days 1 and 8, and docetaxel 100 mg/m(2) day 8, administered 3-weekly for up to 8 cycles, with GCSF support on days 9-15. Patients who had received previous radiotherapy were treated at 75% dose. Patients were evaluated for response by RECIST 1.0 after cycles 2, 4, 6 and 8, and 3-monthly after completing treatment. RESULTS: Forty-four patients were evaluable for response. Eligible patients had histologically proven leiomyosarcoma of the uterus (54.5%) or other sites (45.5%). Thirty-nine patients (84.4%) had metastatic disease, and 5 (15.6%) had locally advanced disease. Six patients (13.6%) had grade 1 disease, and 23 (75%) had grade 2/3 disease. All patients had demonstrated disease progression prior to trial entry. Responses were as follows: partial response 11 (25.0%), stable disease (confirmed) 16 (36.6%), stable disease (unconfirmed) 7 (15.9%), progressive disease 10 (22.7%). Median progression-free survival and overall survival were 7.1 months (95% CI 5.7-8.3) and 17.9 months (95% CI 10.6-25.2), respectively. Progression free rates at 3 and 6 months were 70.5% (95% CI 56.7-84.2%) and 59.1% (95% CI 44.3-73.9%). CONCLUSIONS: This study demonstrates gemcitabine and docetaxel to be active in locally advanced/metastatic leiomyosarcoma in the first line setting. Further investigation comparing with current standard therapies for leiomyosarcoma is warranted.

RESUMEN

This article reviews the role that hyperbaric oxygen therapy (HBOT) plays in the field of wound healing. HBOT, although not seen as a common method of wound management in the UK, can perhaps offer another avenue to managing recalcitrant wounds. In order for the healing of chronic wounds to progress, the practitioner must address all the factors impeding the healing process, one of which is oxygenation. HBOT is thought to improve many aspects of poor healing by supplying high levels of oxygen at normal atmospheric pressure. It has been suggested that increasing the availability of oxygen does not necessarily stimulate the healing process, but that perhaps the pressure at which the oxygen is delivered is the responsible stimulus.

Asunto(s)

Oxigenoterapia Hiperbárica , Cicatrización de Heridas/fisiología , Heridas y Lesiones/terapia , Enfermedad Crónica , Citocinas/genética , Regulación de la Expresión Génica/genética , Humanos , Vasoconstricción/fisiología , Cicatrización de Heridas/genética