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2.
Anaesthesia ; 73(5): 612-618, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29322502

RESUMO

Throat packs are commonly inserted by anaesthetists after induction of anaesthesia for dental, maxillofacial, nasal or upper airway surgery. However, the evidence supporting this practice as routine is unclear, especially in the light of accidentally retained throat packs which constitute 'Never Events' as defined by NHS England. On behalf of three relevant national organisations, we therefore conducted a systematic review and literature search to assess the evidence base for benefit, and also the extent and severity of complications associated with throat pack use. Other than descriptions of how to insert throat packs in many standard texts, we could find no study that sought to assess the benefit of their insertion by anaesthetists. Instead, there were many reports of minor and major complications (the latter including serious postoperative airway obstruction and at least one death), and many descriptions of how to avoid complications. As a result of these findings, the three national organisations no longer recommend the routine insertion of throat packs by anaesthetists but advise caution and careful consideration. Two protocols for pack insertion are presented, should their use be judged necessary.


Assuntos
Manuseio das Vias Aéreas/efeitos adversos , Manuseio das Vias Aéreas/métodos , Anestesia/métodos , Faringe , Adulto , Anestesistas , Medicina Baseada em Evidências , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
3.
J Laryngol Otol ; 126(11): 1169-71, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22932648

RESUMO

BACKGROUND: Hereditary haemorrhagic telangiectasia is an autosomal dominant condition characterised by multiple venous malformations of the skin and mucous membranes which can bleed on contact. A Young's procedure is used to control severe epistaxis in patients with this condition. However, there has been no previous report of a reversal of Young's procedure in such a patient. OBJECTIVE: A patient with hereditary haemorrhagic telangiectasia had his Young's procedure reversed under general anaesthetic by dividing the mucocutaneous flaps. Nasal vestibule patency was maintained using a custom-made silicone nasal mould. Intra-operative photographs show the patient's nasal mucosa shortly following reversal of his Young's procedure, and also illustrate the creation of the custom-made nasal mould. CONCLUSION: Stopping airflow through the nasal cavity via a Young's procedure prevents the telangiectasia from bleeding but does not make them disappear completely. Young's procedure does not seem to have any long-lasting effect on the nasal mucosa of patients with hereditary haemorrhagic telangiectasia.


Assuntos
Epistaxe/cirurgia , Cavidade Nasal/cirurgia , Telangiectasia Hemorrágica Hereditária/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
4.
J Neuroendocrinol ; 22(2): 92-101, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20002965

RESUMO

The available evidence continues to illustrate an inhibitory influence of male gonadal activity on the hypothalamic-pituitary-adrenal (HPA) axis under acute stress. However, far less is known about how these systems interact during repeated stress. Because HPA output consistently declines across studies examining repeated restraint, the potential mechanisms mediating this habituation are often inferred as being equivalent, even though these studies use a spectrum of restraint durations and exposures. To test this generalisation, as well as to emphasise a potential influence of the male gonadal axis on the process of HPA habituation, we compared the effects of two commonly used paradigms of repeated restraint in the rodent: ten daily episodes of 0.5 h of restraint and five daily episodes of 3 h of restraint. Both paradigms produced comparable declines in adrenocorticotrophic hormone and corticosterone between the first and last day of testing. However, marked differences in testosterone levels, as well as corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP) expression, occurred between the two stress groups. Plasma testosterone levels remained relatively higher in animals exposed to 0.5 h of restraint compared to 3 h of restraint, whereas forebrain gonadotrophin-releasing hormone (GnRH) cell counts increased in both groups. AVP mRNA was increased after 3 h, but not after 0.5 h of repeated restraint, in the medial parvicellular paraventricular nucleus and in the posterior bed nucleus of the stria terminalis (BST), and increased with 0.5 h of repeated restraint in the medial amygdala. CRH mRNA was increased after 3 h, but not after 0.5 h of repeated restraint, in the central amygdala and anterior BST. The data obtained illustrate that, despite comparable declines in HPA responses, the pathways recruited for stress adaptation appear to be distinct between restraint groups. Given the extreme sensitivity of limbic AVP to testosterone, and conversely CRH to circulating glucocorticoids, whether differences in endocrine profiles might explain these neuropeptide differences remains to be seen. Nonetheless, the present study provides several new entry points for testing gonadal influences on stress-specific HPA habituation.


Assuntos
Hormônios/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Neuropeptídeos/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Restrição Física/métodos , Estresse Psicológico/metabolismo , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/metabolismo , Envelhecimento , Animais , Arginina Vasopressina/metabolismo , Encéfalo/metabolismo , Corticosterona/sangue , Corticosterona/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Habituação Psicofisiológica/fisiologia , Hormônios/sangue , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/sangue , Testículo/metabolismo , Testosterona/sangue , Testosterona/metabolismo , Fatores de Tempo
5.
Mar Pollut Bull ; 58(10): 1505-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19540535

RESUMO

Locating areas of seafloor contamination caused by heavy oil spills is challenging, in large part because of observational limitations in aquatic subsurface environments. Accepted methods for surveying and locating sunken oil are generally slow, labor intensive and spatially imprecise. This paper describes a method to locate seafloor contamination caused by heavy oil fractions using in situ mass spectrometry and concurrent acoustic navigation. We present results of laboratory sensitivity tests and proof-of-concept evaluations conducted at the US Coast Guard OHMSETT national oil spill response test facility. Preliminary results from a robotic seafloor contamination survey conducted in deep water using the mass spectrometer and a geo-referenced acoustic navigation system are also described. Results indicate that this technological approach can accurately localize seafloor oil contamination in real-time at spatial resolutions better than a decimeter.


Assuntos
Desastres , Poluentes Ambientais/análise , Sedimentos Geológicos/análise , Espectrometria de Massas/métodos , Petróleo/análise , Geografia , Espectrometria de Massas/instrumentação , Oceanos e Mares
6.
Br J Pharmacol ; 151(7): 1061-70, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17549048

RESUMO

BACKGROUND AND PURPOSE: Racemic (R,S) AM1241 is a cannabinoid receptor 2 (CB(2))-selective aminoalkylindole with antinociceptive efficacy in animal pain models. The purpose of our studies was to provide a characterization of R,S-AM1241 and its resolved enantiomers in vitro and in vivo. EXPERIMENTAL APPROACH: Competition binding assays were performed using membranes from cell lines expressing recombinant human, rat, and mouse CB(2) receptors. Inhibition of cAMP was assayed using intact CB(2)-expressing cells. A mouse model of visceral pain (para-phenylquinone, PPQ) and a rat model of acute inflammatory pain (carrageenan) were employed to characterize the compounds in vivo. KEY RESULTS: In cAMP inhibition assays, R,S-AM1241 was found to be an agonist at human CB(2), but an inverse agonist at rat and mouse CB(2) receptors. R-AM1241 bound with more than 40-fold higher affinity than S-AM1241, to all three CB(2) receptors and displayed a functional profile similar to that of the racemate. In contrast, S-AM1241 was an agonist at all three CB(2) receptors. In pain models, S-AM1241 was more efficacious than either R-AM1241 or the racemate. Antagonist blockade demonstrated that the in vivo effects of S-AM1241 were mediated by CB(2) receptors. CONCLUSIONS AND IMPLICATIONS: These findings constitute the first in vitro functional assessment of R,S-AM1241 at rodent CB(2) receptors and the first characterization of the AM1241 enantiomers in recombinant cell systems and in vivo. The greater antinociceptive efficacy of S-AM1241, the functional CB(2) agonist enantiomer of AM1241, is consistent with previous observations that CB(2) agonists are effective in relief of pain.


Assuntos
Receptor CB2 de Canabinoide/agonistas , Analgésicos/farmacologia , Animais , Benzoxazinas/farmacologia , Células CHO , Bloqueadores dos Canais de Cálcio/farmacologia , Canfanos/farmacologia , Canabinoides/química , Canabinoides/metabolismo , Canabinoides/farmacologia , Carragenina/toxicidade , Colforsina/farmacologia , Cricetinae , Cricetulus , AMP Cíclico/antagonistas & inibidores , AMP Cíclico/metabolismo , Cicloexanóis/farmacologia , Relação Dose-Resposta a Droga , Humanos , Hiperalgesia/induzido quimicamente , Hiperalgesia/fisiopatologia , Hiperalgesia/prevenção & controle , Indóis/farmacologia , Camundongos , Morfolinas/farmacologia , Naftalenos/farmacologia , Ligação Proteica/efeitos dos fármacos , Pirazóis/farmacologia , Ensaio Radioligante , Ratos , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo , Especificidade da Espécie , Estereoisomerismo , Trítio
8.
Neuroscience ; 141(4): 1793-800, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16797852

RESUMO

This study investigated the involvement of estrogen receptors alpha and beta in estradiol-induced enhancement of hippocampal neurogenesis in the adult female rat. Subtype selective estrogen receptor agonists, propyl-pyrazole triol (estrogen receptor alpha agonist) and diarylpropionitrile (estrogen receptor beta agonist) were examined for each receptor's contribution, individual and cooperative, for estradiol-enhanced hippocampal cell proliferation. Estradiol increases hippocampal cell proliferation within 4 h [Ormerod BK, Lee TT, Galea LA (2003) Estradiol initially enhances but subsequently suppresses (via adrenal steroids) granule cell proliferation in the dentate gyrus of adult female rats. J Neurobiol 55:247-260]. Therefore, animals received s.c. injections of estradiol (10 microg), propyl-pyrazole triol and diarylpropionitrile alone (1.25, 2.5, 5.0 mg/0.1 ml dimethylsulfoxide) or in combination (2.5 mg propyl-pyrazole triol+2.5 mg diarylpropionitrile/0.1 ml dimethylsulfoxide) and 4 h later received an i.p. injection of the cell synthesis marker, bromodeoxyuridine (200 mg/kg). Diarylpropionitrile enhanced cell proliferation at all three administered doses (1.25 mg, P<0.008; 2.5 mg, P<0.003; 5 mg, P<0.005), whereas propyl-pyrazole triol significantly increased cell proliferation (P<0.0002) only at the dose of 2.5 mg. Our results demonstrate both estrogen receptor alpha and estrogen receptor beta are individually involved in estradiol-enhanced cell proliferation. Furthermore both estrogen receptor alpha and estrogen receptor beta mRNA was found co-localized with Ki-67 expression in the hippocampus albeit at low levels, indicating a potential direct influence of each receptor subtype on progenitor cells and their progeny. Dual receptor activation resulted in reduced levels of cell proliferation, supporting previous studies suggesting that estrogen receptor alpha and estrogen receptor beta may modulate each other's activity. Our results also suggest that a component of estrogen receptor-regulated cell proliferation may take place through alternative ligand and/or cell-signaling mechanisms.


Assuntos
Proliferação de Células/efeitos dos fármacos , Giro Denteado/citologia , Receptor alfa de Estrogênio/agonistas , Receptor beta de Estrogênio/agonistas , Nitrilas/farmacologia , Propionatos/farmacologia , Pirazóis/farmacologia , Análise de Variância , Animais , Bromodesoxiuridina/metabolismo , Contagem de Células/métodos , Relação Dose-Resposta a Droga , Proteínas do Domínio Duplacortina , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Antígeno Ki-67/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/metabolismo , Fenóis , Ratos
10.
J Laryngol Otol ; 120(9): 713-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16700956

RESUMO

Antibiotic-resistant bacteria are increasingly common and present a major problem for the modern day ENT surgeon. This article reviews the development of methicillin resistance in Staphylococcus aureus and how it has come to affect ENT practice. We look at the evidence behind measures taken to help deal with methicillin-resistant Staphylococcus aureus (MRSA) and to prevent its spread. We go on to suggest a departmental guideline for infection control, which we hope can be implemented to help deal with the problems created by MRSA.


Assuntos
Resistência a Meticilina , Otolaringologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Humanos , Controle de Infecções , Cuidados Pré-Operatórios , Infecções Estafilocócicas/diagnóstico , Infecção da Ferida Cirúrgica/microbiologia
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(6 Pt 2): 067603, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17280178

RESUMO

The modulational instability of broadband optical pulses in a four-state atomic system is investigated. In particular, starting from a recently derived generalized nonlinear Schrödinger equation, a wave-kinetic equation is derived. A comparison between coherent and random-phase wave states is made. It is found that the spatial spectral broadening can contribute to the nonlinear stability of ultrashort optical pulses. In practical terms, this could be achieved by using random-phase plate techniques.

12.
J R Soc Med ; 98(9): 415, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16140853

RESUMO

To investigate a suspicion that many ear, nose and throat patients have unfounded concerns about cancer, we questioned 50 patients who had attended a routine clinic after screening-out of those with possibly cancer-related features. None of the 50 proved to have cancer. 15 (30%) had been worried about cancer and 7 of these were still worried despite the consultation. Unwarranted fears about cancer are best dealt with by the referring clinician, especially when the wait for an appointment will be long. Such fears also need to be recognized and addressed by the specialist.


Assuntos
Ansiedade , Medo , Neoplasias de Cabeça e Pescoço/psicologia , Otorrinolaringopatias/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Otolaringologia , Otorrinolaringopatias/diagnóstico , Ambulatório Hospitalar , Pacientes Ambulatoriais , Projetos Piloto , Inquéritos e Questionários , Listas de Espera
13.
Lasers Surg Med ; 34(4): 310-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15083491

RESUMO

BACKGROUND AND OBJECTIVES: To compare the efficacy and safety of inferior turbinate reduction in children using Holmium:YAG (Ho:Yag) laser and diathermy. Histological effects of these treatments on turbinate tissue are also studied. STUDY DESIGN/MATERIALS AND METHODS: A retrospective review and structured telephone interview of paediatric cases treated with Ho:Yag laser and diathermy to inferior turbinates. The complications, morbidity and efficacy were quantified. Histological sections of inferior turbinates treated with diathermy (surface and submucosal) and laser were compared. RESULTS: Efficacy in the laser (n = 8) and diathermy group (n = 11) was similar. The complication/morbidity score was lower in the laser group, 1.92 versus 3.48, (P = 0.04, CI: 0.01, 2). Long-term benefit was 50 and 36% in the laser and diathermy group respectively. Histology showed very limited tissue damage in all methods of treatment. CONCLUSIONS: Ho:Yag laser treatment is equally efficacious, but causes less complications and morbidity compared to surface diathermy. Both treatment methods have poor long-term efficacy, which may be related to limited tissue damage.


Assuntos
Eletrocoagulação/métodos , Terapia a Laser/instrumentação , Obstrução Nasal/cirurgia , Conchas Nasais/cirurgia , Adolescente , Criança , Feminino , Humanos , Hipertrofia/etiologia , Masculino , Obstrução Nasal/etiologia , Estudos Retrospectivos , Rinite/complicações , Resultado do Tratamento , Conchas Nasais/patologia
14.
Laryngoscope ; 113(6): 1034-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12782817

RESUMO

OBJECTIVE: To report the results of endoscopic laser-assisted dacryocystorhinostomy in anticoagulated patients. STUDY DESIGN: A retrospective study of 16 consecutive anticoagulated patients with distal nasolacrimal duct obstruction treated by endoscopic laser-assisted dacryocystorhinostomy. METHODS: A case note review was made of all patients treated with endoscopic laser-assisted dacryocystorhinostomy who were taking coumadin in two centers between 1993 and 2000. The parameters of age, gender, indications for surgery, surgical findings, complications, and outcome were analyzed. The mean follow-up time was 14 months (range, 9-26 mo). RESULTS: Fifteen of the 16 patients who were treated had an eventual successful outcome, but 6 patients required revision surgery. The patient whose symptoms were not improved was shown to have functional epiphora. No patient had a problem with primary or secondary epistaxis, and no patient required admission. A major benefit was the lack of disruption of anticoagulant therapy. CONCLUSIONS: Endoscopic laser-assisted dacryocystorhinostomy is a safe, efficient technique for the relief of distal nasolacrimal duct obstruction in anticoagulated patients. Not only does it avoid any disruption to their anticoagulant therapy, but it also can be performed as an outpatient procedure.


Assuntos
Anticoagulantes/efeitos adversos , Dacriocistorinostomia , Endoscopia , Terapia a Laser , Varfarina/efeitos adversos , Adulto , Idoso , Procedimentos Cirúrgicos Ambulatórios , Anticoagulantes/uso terapêutico , Feminino , Seguimentos , Humanos , Doenças do Aparelho Lacrimal/sangue , Doenças do Aparelho Lacrimal/cirurgia , Obstrução dos Ductos Lacrimais/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Fatores de Risco , Reino Unido , Varfarina/uso terapêutico
15.
J Laryngol Otol ; 115(5): 380-4, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11410129

RESUMO

Nasal obstruction is common in children, and is often attributed to adenoid enlargement. This prospective study was performed to determine whether routine nasal endoscopy is of value for children undergoing surgery for nasal obstruction. Forty-eight children aged two to nine years undergoing adenoidectomy, and six normal controls, were examined under general anaesthesia with a 4 mm rigid endoscope. A video of the endoscopy was subsequently assessed independently by an observer blinded to the original findings and the presence of nasal symptoms. The endoscopist and independent assessor were in agreement regarding 86 per cent of the findings. Three quarters of the children had abnormalities on endoscopy in addition to enlarged adenoids, and in 23 per cent these were potentially of major clinical significance (unsuspected foreign body, gross septal deviation, gross hypertrophy of the turbinates). Endoscopy produced no post-operative complications and was possible in children as young as two years of age, without decongestants. Nasal endoscopy is a safe, objective and useful means of identifying potentially significant abnormalities in children with nasal obstruction.


Assuntos
Endoscopia/métodos , Obstrução Nasal/diagnóstico , Adenoidectomia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Obstrução Nasal/cirurgia , Septo Nasal/anormalidades , Estudos Prospectivos
16.
Int J Pediatr Otorhinolaryngol ; 58(3): 223-8, 2001 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-11335010

RESUMO

BACKGROUND: the efficacy of adenoidectomy in relieving nasal symptoms has been questioned. Although enlarged adenoids are often blamed for nasal obstruction, other causes can be missed if examination is not thorough. We suggest that endoscopy at the time of adenoidectomy may be useful to confirm large adenoids and exclude other causes, and the findings may help predict residual symptoms 2 years after adenoidectomy. METHOD: a prospective study of a consecutive series of children undergoing adenoidectomy for nasal obstruction was performed. All underwent endoscopy with a 4-mm rigid endoscope without decongestants under GA immediately prior to adenoidectomy. Two years later a postal symptom questionnaire was sent, with telephone follow up for non-responders. The findings on endoscopy were compared with residual symptoms at 2 years. RESULTS: Forty-eight children aged 2-9 (mean 4) years were enrolled, 26 of them female. At 2 years follow up, data were available for 34 children (71%). Complete obstruction of the posterior choanae of the nose by adenoids was seen in 21 (62%). Additional findings (e.g. septal deviation, hypertrophic mucosa on the turbinates) were present in 22 (65%). Of them 9 (26%) had residual nasal symptoms. Of the children with less than occlusive adenoids, six (50%) out of 12 had residual symptoms, compared with three (14%) out of 21 with occlusive adenoids (chi(2)=4.91, P<0.05). Although residual symptoms were more common in those with additional findings on the original endoscopy (32 vs. 17%), this did not reach statistical significance. CONCLUSIONS: residual nasal symptoms are common when children are followed up in the medium term. The findings on endoscopy may predict the success of adenoidectomy in relieving the symptoms, and may help to guide further treatment.


Assuntos
Adenoidectomia , Tonsila Faríngea/patologia , Endoscopia , Obstrução Nasal/cirurgia , Nariz/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Hipertrofia , Masculino , Obstrução Nasal/etiologia , Obstrução Nasal/patologia , Estudos Prospectivos
17.
Orbit ; 18(3): 217-222, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12045988

RESUMO

Over the past 3 years we have treated 4 patients with nasolacrimal duct obstruction secondary to sarcoidosis. These patients have had mixed outcomes following endonasal laser-assisted dacryocystorhinostomy (DCR). A literature search from 1966 to the present yielded a further 11 cases of patients thought to have sarcoid who underwent DCR. The outcome of these 15 patients indicate that while all were initially successful, the subsequent failure rate is high. These patients are older than the majority of patients with sarcoidosis and there is a female preponderance. Systemic steroids reversed obstruction in one patient. We recommend nasal examination in all patients with nasal symptoms in whom DCR is proposed to help identify sarcoidosis or other intranasal disease and/or to allow treatment of specific diseases prior to surgery.

18.
J Laryngol Otol ; 113(10): 948-50, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10664719

RESUMO

Laryngeal involvement by cutaneous lymphoma is rare; it may be isolated or part of systemic spread. We report a case of cutaneous T-cell lymphoma with isolated extracutaneous spread to the larynx, confirmed by the polymerase chain reaction in addition to histology. Awareness of this association may allow early recognition of symptoms heralding laryngeal embarrassment.


Assuntos
Neoplasias Laríngeas/secundário , Linfoma Cutâneo de Células T/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/patologia , Idoso , Terapia Combinada , Feminino , Rearranjo Gênico do Linfócito T , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/terapia , Perna (Membro) , Linfoma Cutâneo de Células T/radioterapia , Linfoma Cutâneo de Células T/cirurgia , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/cirurgia , Reação em Cadeia da Polimerase , Neoplasias Cutâneas/radioterapia , Neoplasias Cutâneas/cirurgia
19.
Lasers Med Sci ; 14(2): 158-62, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24519172

RESUMO

Silicone voice prostheses, or valves, are inserted into the common tracheo-oesophageal wall of patients after laryngectomy, to allow speech rehabilitation. Granulation tissue around these voice prostheses is often removed by laser and the safety of these valves with lasers had not been confirmed. The common valves were exposed to increasing energies from the carbon dioxide, potassium-titanyl-phosphate and holmium YAG lasers, in air. The energies used were those in common clinical use. The Provox valves proved especially vulnerable to all laser energies. Other methods of removing granulation tissue should be tried prior to lasering, or the valves should be removed, as damage to them, or the patient's airway, can result.

20.
Biol Bull ; 196(1): 94-104, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25575389

RESUMO

The solitary ascidian Corella inflata is a common fouling organism in many areas of Puget Sound and the San Juan Archipelago, Washington, USA. Despite its abundance, it is conspicuously absent from areas that receive direct sunlight. Previous work suggests that ascidians in unshaded habitats can be overgrown and killed by algal overgrowth. In this study, we tested the hypothesis that UV irradiation contributes to C. inflata distribution by killing individuals exposed to direct sunlight. To test this, we exposed C. inflata embryos, larvae, juveniles, and adults to UV irradiation and measured the responses. We also tested for UV-absorbing compounds in larvae, juveniles, and adults. In the laboratory, UV significantly damaged all life stages; the earliest stages were most vulnerable. A 3-week UV exposure significantly shortened adult life span. Juveniles suffered 100% mortality after only 3 days. Tadpole larvae decreased settlement and metamorphosis after 1 day of UV exposure, and embryos exhibited developmental abnormalities after only 30 minutes of exposure. None of the life-history stages had apparent UV-absorbing compounds. Given the vulnerability of this species to UV, we suggest that its unique life-history traits (i.e., time of spawning, brooding behavior, length of larval life) help it persist in its preferred habitat and avoid dispersal into inappropriate, UV-exposed areas.

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