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OBJECTIVE: Necrotising otitis externa is increasingly being seen and treated within the UK. The aim of this study was to explore the potential cost of a cohort of patients with necrotising otitis externa presenting to a single tertiary NHS trust. METHOD: This was a retrospective study with data from 14 patients with confirmed necrotising otitis externa who were treated, monitored, discharged or who died between October 2016 and November 2018. Direct costs using the tariffs from the 2018 to 2019 financial year included in-patient stay, imaging, peripheral inserted central catheter line cost, ENT and out-patient parenteral antibiotic therapy visits and antimicrobial duration. RESULTS: The mean cost of treatment per patient was £17 615 (range, £9407 to £38 230) with an extreme outlier costing more than £122 000. CONCLUSION: Awareness and education at a primary care level and research into robust imaging to aid termination of treatment may lower costs in the future by catching pathology early and reducing treatment duration.
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Otitis Externa , Antibacterianos/uso terapéutico , Estrés Financiero , Humanos , Otitis Externa/tratamiento farmacológico , Estudios Retrospectivos , Medicina EstatalRESUMEN
BACKGROUND: Malignant otitis externa is a potentially fatal infection of the skull base. With an ageing population and increasing prevalence of diabetes, the incidence of malignant otitis externa in the British population is rising. To date, there remain no accepted diagnostic criteria, few prognostic indicators and no consensus treatment pathways. METHOD: A prospective case series was conducted at a tertiary referral teaching hospital. RESULTS: A cohort of susceptible individuals predominates (elderly, male, with immunosuppression and diabetes), with 25 per cent reporting a preceding incident. Otorrhoea, otalgia and canal granulation were the commonest presenting features, alongside positive pseudomonas cultures. No clear markers for predicating disease severity were isolated; however, a high initial haemoglobin A1c level demonstrated a significant moderately positive correlation with length of treatment. CONCLUSION: A treatment pathway designed to provide a standardised approach to investigation and treatment is proposed, which aims to increase earlier diagnosis, streamline care and facilitate the development of best practice.
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Algoritmos , Sistemas de Apoyo a Decisiones Clínicas , Neoplasias del Oído/terapia , Otitis Externa/terapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Oído/diagnóstico , Femenino , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Otitis Externa/diagnóstico , Guías de Práctica Clínica como Asunto , Estudios Prospectivos , Reino UnidoRESUMEN
OBJECTIVE: This paper highlights the importance of reporting air-bone gap closure in stapes surgery according to the American Academy of Otolaryngology - Head and Neck Surgery guidelines and reviews compliance in recent years. METHODS: A retrospective case series was conducted and the outcomes were reviewed. Closure of the air-bone gap was calculated in 204 adult patients using the aforementioned guidelines. Results were recalculated ignoring the Carhart phenomenon to determine any significant difference. Adherence to guidelines was also reported as a secondary outcome. RESULTS: Ignoring the Carhart phenomenon resulted in 75 per cent over-reporting of successful air-bone gap closure (p < 0.001). Over-reporting occurred in 5.9 per cent of papers, and in 11.8 per cent it was difficult to determine how the results were reached. CONCLUSION: Despite the existence of clear guidelines, stapes surgery outcomes are still being over-reported as successful. This can lead to incorrect information being provided to patients during the consent process and makes comparative studies difficult.
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Conducción Ósea/fisiología , Documentación/normas , Adhesión a Directriz , Pérdida Auditiva Conductiva/cirugía , Otosclerosis/cirugía , Cirugía del Estribo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Audiometría , Femenino , Pérdida Auditiva Conductiva/etiología , Humanos , Masculino , Persona de Mediana Edad , Otosclerosis/complicaciones , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
Bait collection is a multibillion dollar worldwide activity that is often managed ineffectively. For managers to understand the impacts on protected inter-tidal mudflats and waders at appropriate spatial scales macrofaunal surveys combined with video recordings of birds and bait collectors were undertaken at two UK sites. Dug sediment constituted approximately 8% of the surveyed area at both sites and is less muddy (lower organic content) than undug sediment. This may have significant implications for turbidity. Differences in the macrofaunal community between dug and undug areas if the same shore height is compared as well as changes in the dispersion of the community occurred at one site. Collection also induces a 'temporary loss of habitat' for some birds as bait collector numbers negatively correlate with wader and gull abundance. Bait collection changes the coherence and ecological structure of inter-tidal mudflats as well as directly affecting wading birds. However, as ß diversity increased we suggest that management at appropriate hectare/site scales could maximise biodiversity/function whilst still supporting collection.
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Biodiversidad , Aves , Ecosistema , Animales , EcologíaRESUMEN
BACKGROUND: Since the development of intratympanic aminoglycoside in the 1950s, otologists have been able to chemically ablate the vestibule. We present the results of using low-dose intratympanic gentamicin to treat Ménière's disease. METHOD: A retrospective review was performed of all patients who underwent low-dose intratympanic gentamicin therapy over seven years. Data on gender, age, number of procedures, pure tone audiometry and symptom control were analysed. RESULTS: In all, 38 patients underwent low-dose intratympanic gentamicin therapy. These comprised 25 females and 13 males, with an average age of 58.4 years. Hearing was preserved in 87.5 per cent of patients, with no significant difference before and after treatment (p = 0.744). In all, 85.7 per cent of patients had complete or substantial symptom control (classes A and B, respectively). CONCLUSION: Low-dose intratympanic gentamicin therapy was effective in controlling the symptoms of Ménière's disease patients, while preserving hearing.
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Antibacterianos/administración & dosificación , Gentamicinas/administración & dosificación , Enfermedad de Meniere/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Audiometría de Tonos Puros , Estudios de Cohortes , Femenino , Humanos , Inyección Intratimpánica , Masculino , Enfermedad de Meniere/fisiopatología , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
The present study investigates the relationships between copper (Cu) and zinc (Zn) concentrations in sediment, pore water and their bioaccumulation in the polychaete Nereis (Alitta) virens, as well as the importance of site-specific sediment characteristics in that process. Sediment, pore water and N. virens were sampled from seven sites with different pollution histories along the English Channel coast. Results showed that site-specific metal levels and sediment characteristics were important in determining the bioavailability of metals to worms. Significant correlations were found between Cu in the sediment and in the pore water and between Zn in the pore water and in N. virens. Zn from the pore water was thus more readily available from a dissolved source to N. virens than Cu. Data also showed that metal concentrations in N. virens were lower than those found in other closely related polychaetes, indicating that it may regulate tissue concentrations of Cu and Zn.
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Monitoreo del Ambiente/métodos , Metales/análisis , Poliquetos/fisiología , Contaminantes Químicos del Agua/análisis , Animales , Disponibilidad Biológica , Cobre , Sedimentos Geológicos/química , Metales/metabolismo , Agua , Contaminantes Químicos del Agua/metabolismo , ZincRESUMEN
OBJECTIVE: The aim of this paper was to propose a guideline for the management of intrinsic facial nerve tumours based on our practice and findings in the literature. METHOD: A retrospective review of intrinsic facial nerve tumours over the last 15 years was performed. Parameters measured included age, presenting symptoms, pre- and post-treatment hearing and House-Brackmann grading, tumour position, treatment and duration of follow up. RESULTS: A total of 15 patients presented with intrinsic facial nerve tumours over the study period. The most common presenting complaint was facial symptoms (93.3 per cent), followed by hearing loss (46.7 per cent). Three patients with stable facial nerve function (House-Brackmann grades II-III) were treated conservatively. Twelve patients underwent surgery to treat progressive or recurrent symptoms. Facial function was maintained or improved in 60.0 per cent of patients and hearing was preserved in 66.7 per cent. CONCLUSION: We propose that all stable tumours associated with good facial function of grade III or below should be treated conservatively. For symptomatic or progressive lesions, tailored surgery depending on the tumour site and hearing level should be offered to preserve native nerve function and facial musculature. For patients with prolonged paralysis, tumours can be monitored and other forms of facial reanimation and support offered.
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Neoplasias de los Nervios Craneales/cirugía , Enfermedades del Nervio Facial/cirugía , Parálisis Facial/terapia , Hueso Temporal/inervación , Adulto , Anciano , Neoplasias de los Nervios Craneales/complicaciones , Nervio Facial/cirugía , Enfermedades del Nervio Facial/complicaciones , Parálisis Facial/etiología , Femenino , Pérdida Auditiva/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVE: This study investigated whether patients who remain symptomatic more than a year following idiopathic facial paralysis gain benefit from tailored facial physiotherapy. METHODS: A two-year retrospective review was conducted of all symptomatic patients. Data collected included: age, gender, duration of symptoms, Sunnybrook facial grading system scores pre-treatment and at last visit, and duration of treatment. RESULTS: The study comprised 22 patients (with a mean age of 50.5 years (range, 22-75 years)) who had been symptomatic for more than a year following idiopathic facial paralysis. The mean duration of symptoms was 45 months (range, 12-240 months). The mean duration of follow up was 10.4 months (range, 2-36 months). Prior to treatment, the mean Sunnybrook facial grading system score was 59 (standard deviation = 3.5); this had increased to 83 (standard deviation = 2.7) at the last visit, with an average improvement in score of 23 (standard deviation = 2.9). This increase was significant (p < 0.001). CONCLUSION: Tailored facial therapy can improve facial grading scores in patients who remain symptomatic for prolonged periods.
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Parálisis de Bell/terapia , Modalidades de Fisioterapia/estadística & datos numéricos , Adulto , Anciano , Toxinas Botulínicas Tipo A/uso terapéutico , Músculos Faciales , Nervio Facial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fármacos Neuromusculares/uso terapéutico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To determine the effectiveness of biocements in rebridging isolated incudostapedial erosion. METHODS: A review of the use of biocements for isolated incudostapedial joint erosion was performed on publications from 1998 to 2012 available from Medline, Embase and Pubmed. Inclusion criteria were papers published in English, case series or comparative studies with more than 10 patients, isolated incudostapedial erosion through chronic ear disease, minimal air-bone gap less than 20 dB (or air-bone gap less than 10 dB) and follow up for at least one year. RESULTS: In 108 patients, rebridging ossiculoplasty was performed using hydroxyapatite cement. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 80-94.4 per cent and 29-75 per cent, respectively. Glass ionomer cement was used in 318 patients. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 74-94 per cent and 40-76 per cent, respectively. CONCLUSION: Biocements can be successfully used to close isolated incudostapedial erosions. Larger comparative prospective studies documenting the length of eroded incus and types of reformation of the incudostapedial joint, with standardised reporting, are needed in the future.
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Cementos para Huesos , Durapatita , Pérdida Auditiva/cirugía , Yunque/patología , Estribo/patología , Osículos del Oído , Pérdida Auditiva/etiología , HumanosRESUMEN
OBJECTIVE: To demonstrate that Blu-tack is equally effective at attenuating sound as over-the-counter ear plugs. METHODS: Nineteen healthy volunteers had their hearing thresholds assessed before and after the insertion of over-the-counter ear plugs. The results were compared with hearing thresholds following the insertion of Blu-tack. Thresholds were tested at: 0.5, 1, 2, 3, 4, 6 and 8 kHz. The differences were compared, and p values of less than 0.02 were regarded as significant. Using a visual analogue scale, volunteers were asked to assess the comfort and ease of insertion of the ear plugs and Blu-tack, and their peace of mind whilst using the ear plugs and Blu-tack. RESULTS: Blu-tack was less effective at attenuating sound at low frequencies, but was as effective as over-the-counter ear plugs at attenuating sound above 3 kHz. Blu-tack was significantly more comfortable to wear (p = 0.006). There was no difference in terms of ease of insertion and peace of mind. CONCLUSION: Blu-tack can be regarded as a comfortable alternative to over-the-counter ear plugs for the attenuation of everyday sound.
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Dispositivos de Protección de los Oídos , Adolescente , Adulto , Estudios de Casos y Controles , Dispositivos de Protección de los Oídos/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Sonido/efectos adversos , Adulto JovenRESUMEN
INTRODUCTION: Fourth branchial arch anomalies represent <1% of all branchial anomalies and present as recurrent neck infections or suppurative thyroiditis. Traditionally, management has consisted of treatment of the acute infection followed by hemithyroidectomy, surgical excision of the tract and obliteration of the opening in the pyriform fossa. Recently, it has been suggested that endoscopic obliteration of the sinus tract alone using laser, chemo or electrocautery is a viable alternative to open surgery. OBJECTIVES: To determine the results of endoscopic obliteration of fourth branchial arch fistulae in children in our institute. METHODS: Retrospective case note review of all children undergoing endoscopic treatment of fourth branchial arch anomalies in the last 7 years at the Royal Manchester Children's Hospital. Patient demographics, presenting symptoms, investigations and surgical technique were analysed. The primary and secondary outcome measures were resolution of recurrent infections and incidence of surgical complications, respectively. RESULTS: In total 5 cases were identified (4 females and 1 male) aged between 3 and 12 years. All presented with recurrent left sided neck abscesses. All children underwent a diagnostic laryngo-tracheo-bronchoscopy which identified a sinus in the apex of the left pyriform fossa. This was obliterated using electrocautery in 1 patient, CO2 laser/Silver Nitrate chemocautery in 2 patients and Silver Nitrate chemocautery in a further 2 patients. There were no complications and no recurrences over a mean follow-up period of 25 months (range 11-41 months). CONCLUSION: Endoscopic obliteration of pyriform fossa sinus is a safe method for treating fourth branchial arch anomalies with no recurrence.
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Absceso/cirugía , Región Branquial/anomalías , Región Branquial/cirugía , Electrocoagulación/métodos , Endoscopía/métodos , Cuello/anomalías , Fístula del Sistema Respiratorio/complicaciones , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Cuello/cirugía , Fístula del Sistema Respiratorio/cirugía , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Late gametogenic Nereis virens were incubated for up to 2.5 months in environmentally relevant concentrations of copper-spiked sediment. Sequential extraction confirmed that much more labile copper (in actual and percentage terms) was present as spiked concentrations increased, although the residual fractions contained similar amounts across concentrations. This is also reflected in the tissue concentration of the worms which increased in line with the sediment concentrations. Adult mortality was not dependent on the exposure time, but higher concentrations usually induced greater mortality for both sexes. Oocytes were significantly smaller at higher concentrations although pairwise comparisons did not show specific differences. Spawning of males occurred a number of days earlier in the higher concentrations. Differences in the number of embryos developing normally after in vitro fertilizations of oocytes fertilized with sperm from exposed males and non-exposed males showed that sperm were more susceptible to toxicity, but oocytes were also affected at the highest concentration. These results show that there are direct and indirect reproductive consequences of parental exposure to copper with implications for recruitment and subsequent colonization of polluted sediments for this ecologically and commercially important species.
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Cobre/toxicidad , Poliquetos/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Embrión no Mamífero/efectos de los fármacos , Femenino , Sedimentos Geológicos/química , Masculino , Oocitos/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Análisis de SupervivenciaRESUMEN
OBJECTIVE: We discuss the use of balloon dilatation to relieve supraglottic stenosis caused by mucous membrane plasmacytosis. CASE REPORT: A 54-year-old man with a known diagnosis of mucous membrane plasmacytosis presented with dysphonia and worsening airway obstruction which required a tracheostomy. He underwent balloon dilatation of the supraglottic larynx using an angioplasty balloon within sequentially sized endotracheal tubes. This enabled successful decannulation, with minimal re-stenosis at eight-month follow up. CONCLUSION: To our knowledge, this is the first reported case of supraglottic stenosis caused by plasmacytosis to be successfully treated using this method. We have shown that this minimally invasive technique deals effectively with a complex airway and minimises re-stenosis.
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Dilatación/instrumentación , Laringoestenosis/terapia , Humanos , Laringoestenosis/etiología , Laringoestenosis/patología , Masculino , Persona de Mediana Edad , Membrana Mucosa/patologíaRESUMEN
STUDY DESIGN: Case study. DISCUSSION: The origin of sulcus vocalis is debatable, it may arise from a congenital or acquired cyst that ruptures leaving a sulcus attached to the deep layer of the lamina propria. This has been hypothesized but never shown before. CONCLUSION: In this article, we present the first videographic documentation of an intracordal cyst that over time may have become a sulcus vocalis.
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Quistes/patología , Quistes/fisiopatología , Disfonía/patología , Disfonía/fisiopatología , Pliegues Vocales/patología , Pliegues Vocales/fisiopatología , Adulto , Quistes/cirugía , Progresión de la Enfermedad , Disfonía/cirugía , Femenino , Humanos , Membrana Mucosa/patología , Membrana Mucosa/cirugía , Grabación de Cinta de Video , Pliegues Vocales/cirugíaRESUMEN
OBJECTIVES: To compare the difference in ENT and Audiology visits, treatments dispensed and potential savings pre- and post-bone anchored hearing aid (BAHA) insertion in patients with chronic suppurative otitis media exacerbated by behind the ear hearing aids. DESIGN: A retrospective pilot study. SETTING: District General Hospital. PARTICIPANTS: All patients who had BAHA inserted from January 2001 to January 2006. PARAMETERS: Age, gender, number of visits per month, treatments per month dispensed from the ENT and Audiology Departments and direct and limited indirect medical costs pre- and post-BAHA insertion. RESULTS: Twelve of 26 (46%) adult patients had BAHA inserted over the 5-year period for CSOM. The male to female ratio was 1 : 3 with a median age of 61 (range 29-81). The number of visits and treatments dispensed per month in the ENT Department fell from a mean of 0.42-0.33 (P < 0.08) and 0.22-0.14 (P < 0.02) respectfully. When the difference in medical cost was taken into account BAHA offered a potential saving of pound 627.80 per patient. CONCLUSION: Although the initial acquisition of surgical equipment and BAHA sound processors is expensive, there is a reduction in the number of treatments and visits required for patients with chronic suppurative otitis media after BAHA is inserted leading to a reduction in average costs.
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Audífonos/economía , Otitis Media Supurativa/rehabilitación , Adulto , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/estadística & datos numéricos , Costos y Análisis de Costo , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Reino UnidoRESUMEN
The mating behaviour of the signal crayfish, Pacifastacus leniusculus (Dana), has been categorised into seven distinct stages: orientation; contact; seizure; turning; mounting; spermatophore deposition; and dismounting. These categories were used in the development of a bioassay to test whether mature females release a sex pheromone during the breeding season to which males respond. Water conditioned by 1) mature females (MF water), 2) immature females (IF water) and 3) freshwater (C water), were injected through standard aquarium air-stones into tanks containing mature males. The behaviour of the male was recorded on video for 15 minutes before and after injection of each test water. The time that the males spent exhibiting the three behavioural categories of 'quiescent,' 'motile' and 'handling' of the air-stone, were recorded. 'Handling' of the air-stone included the mating behaviours of seizure, mounting, and spermatophore deposition onto the surface of the air-stone. Males exposed to MF water exhibited significantly increased levels of motile activity and handling behaviour, than males exposed to C water or IF water. These results demonstrate for the first time the presence of a sex pheromone, released during the breeding season by mature females, that stimulates courtship and mating behaviour in male P. leniusculus.
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Cortejo , Decápodos/fisiología , Atractivos Sexuales/farmacología , Conducta Sexual Animal , Animales , Femenino , Masculino , MovimientoRESUMEN
BACKGROUND: The mda-7 gene (melanoma differentiation associated gene-7) is a novel tumor suppressor gene. The anti-proliferative activity of MDA-7 has been previously reported. In this report, we analyze the anti-tumor efficacy of Ad-mda7 in a broad spectrum of cancer lines. MATERIALS AND METHODS: Ad-mda7-transduced cancer or normal cell lines were assayed for cell proliferation (tritiated thymidine incorporation assay, Alamar blue assay, and trypan-blue exclusion assay), apoptosis (TUNEL, and Annexin V staining visualized by fluorescent microscopy or FACs analysis), and cell cycle regulation (Propidium Iodide staining and FACs analysis). RESULTS: Ad-mda7 treatment of tumor cells resulted in growth inhibition and apoptosis in a temporal and dose-dependent manner. The anti-tumor effects were independent of the genomic status of p53, RB, p16, ras, bax, and caspase 3 in these cells. In addition, normal cell lines did not show inhibition of proliferation or apoptotic response to Ad-mda7. Moreover, Ad-mda7-transduced cancer cells secreted a soluble form of MDA-7 protein. Thus, Ad-mda7 may represent a novel gene-therapeutic agent for the treatment of a variety of cancers. CONCLUSIONS: The potent and selective killing activity of Ad-mda7 in cancer cells but not in normal cells makes this vector a potential candidate for cancer gene therapy.
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Terapia Genética/métodos , Sustancias de Crecimiento/genética , Sustancias de Crecimiento/metabolismo , Interleucinas , Neoplasias/terapia , Oxazinas , Xantenos , Adenoviridae/genética , Anexina A5/metabolismo , Western Blotting , División Celular/efectos de los fármacos , Línea Celular , Separación Celular , Mapeo Cromosómico , Cromosomas Humanos Par 1 , Colorantes/farmacología , Relación Dosis-Respuesta a Droga , Exones , Citometría de Flujo , Genes Supresores de Tumor/genética , Humanos , Etiquetado Corte-Fin in Situ , Microscopía Confocal , Microscopía Fluorescente , Propidio/farmacología , Timidina/metabolismo , Factores de Tiempo , Transducción Genética , Azul de Tripano/farmacología , Células Tumorales CultivadasRESUMEN
Endocrine and environmental factors control reproduction of the polynoid scale worm Harmothoe imbricata. We confirmed that the rate of vitellogenesis was greater in winter specimens transferred from ambient regimes of photoperiod and temperature to a light:dark (LD) photoperiod of 16:8 at 10 degrees C and showed that the number of females spawning was significantly greater than for those transferred to LD8:16 at 10 degrees C. The endocrine mediation of this response was investigated using prostomium implantations. Significantly more LD8:16 females implanted with prostomia from LD16:8 conditioned females spawned than LD8:16 females implanted with LD8:16 prostomia. Females without prostomia failed to spawn. LD16:8 exposure may increase levels of a possible "spawning hormone" in the prostomium. Spawning proceeded in these LD16:8 females and allowed spawning to occur in LD8:16 females implanted with LD16:8 prostomia. In LD8:16 prostomia, titers of the spawning hormone reached the threshold in significantly fewer individuals, so that significantly fewer females implanted with LD8:16 prostomia spawned. Using Y-maze choice chambers, pair formation was shown to be under pheromonal control, with males being attracted to mature females but not to females carrying fertilized oocytes or to LD8:16 conditioned females. Production of this attraction pheromone can, therefore, be manipulated through photoperiodic control, suggesting a link between oogenesis, spawning, and pheromone production.
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Poliquetos/fisiología , Animales , Sistema Endocrino/fisiología , Femenino , Masculino , Oocitos/crecimiento & desarrollo , Apareamiento , Feromonas/fisiología , Fotoperiodo , Poliquetos/metabolismoRESUMEN
PTEN, a putative tumour suppressor gene associated with prostate and other cancers, is known to be located within the chromosomal region 10q23.3. Transcription of the PTEN gives rise to multiple mRNA species. Analyses by Northern blots, using cell lines which express PTEN together with cell lines which have lost the PTEN or carry a truncated version of the gene, has allowed us to demonstrate that the pseudogene is not transcribed. In addition, 3' RACE studies confirmed that the multiple mRNA species arising from the gene probably result from the use of alternative polyadenylation sites. No evidence for tissue- or cell-specific patterns of transcription was found. Analysis by 5' RACE placed the putative site for the start of transcription around 830 bp upstream of the start codon. A map of the location of the PTEN gene with a series of overlapping YAC, BAC and PACs has been constructed and the relative position of eight microsatellite markers sited. Two known and one novel marker have been positioned within the gene, the others are in flanking regions. The more accurate location of these markers should help in future studies of the extent of gene loss. Several polymorphisms were also identified, all were within introns. Four of the common polymorphisms appear to be linked. In blood, DNA from 200 individuals, including normal, BPH and prostate cancer patients, confirmed this link. Only two samples of 200 did not carry the linked haplotype, both were patients with advanced prostate cancer. It is possible that such rearrangements within PTEN could be evidence of predisposition to prostate cancer in this small number of cases.