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1.
Ann Surg ; 269(4): 748-755, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29342018

RESUMO

OBJECTIVE: Improvement of ventral hernia repair. BACKGROUND: Despite the use of mesh and other recent improvements, the currently popular techniques of ventral hernia repair have specific disadvantages and risks. METHODS: We developed the endoscopically assisted mini- or less-open sublay (MILOS) concept. The operation is performed transhernially via a small incision with light-holding laparoscopic instruments either under direct, or endoscopic visualization. An endoscopic light tube was developed to facilitate this approach (EndotorchTM Wolf Company). Each MILOS operation can be converted to standard total extraperitoneal gas endoscopy once an extraperitoneal space of at least 8 cm has been created. All MILOS operations were prospectively documented in the German Hernia registry with 1 year questionnaire follow-up. Propensity score matching of incisional hernia operations comparing the results of the MILOS operation with the laparoscopic intraperitoneal onlay mesh operation (IPOM) and open sublay repair from other German Hernia registry institutions was performed. RESULTS: Six hundred fifteen MILOS incisional hernia operations were included. Compared with laparoscopic IPOM incisional hernia operation, the MILOS repair is associated with significantly a fewer postoperative surgical complications (P < 0.001) general complications (P < 0.004), recurrences (P < 0.001), and less chronic pain (P < 0.001). Matched pair analysis with open sublay repair revealed significantly a fewer postoperative complications (P < 0.001), reoperations (P < 0.001), infections (P = 0.007), general complications (P < 0.001), recurrences (P = 0.017), and less chronic pain (P < 0.001). CONCLUSIONS: The MILOS technique allows minimally invasive transhernial repair of incisional hernias using large retromuscular/preperitoneal meshes with low morbidity. The technique combines the advantages of open sublay and the laparoscopic IPOM repair.ClinicalTrials.gov Identifier NCT03133000.


Assuntos
Herniorrafia/métodos , Hérnia Incisional/cirurgia , Laparoscopia , Telas Cirúrgicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peritônio , Estudos Prospectivos
2.
Eur Respir J ; 46(1): 219-29, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25792638

RESUMO

Erlotinib with bevacizumab showed promising activity in recurrent nonsquamous (NS) nonsmall cell lung cancer (NSCLC). The INNOVATIONS study was designed to assess in first-line treatment of unselected cisplatin-eligible patients this combination compared to cisplatin, gemcitabine and bevacizumab. Stage IIIB/IV patients with NS-NSCLC were randomised on erlotinib (150 mg daily) and bevacizumab (15 mg·kg(-1) on day 1, every 3 weeks) (EB) until progression, or cisplatin (80 mg·m(-2) on day 1, every 3 weeks) and gemcitabine (1250 mg·m(-2) on days 1 and 8, every 3 weeks) up to six cycles and bevacizumab (15 mg·kg(-1) on day 1, every 3 weeks) (PGB) until progression. 224 patients were randomised (EB n=111, PGB n=113). The response rate (12% versus 36%; p<0.0001), progression-free survival (median 3.5 versus 6.9 months; hazard ratio (HR) 1.85, 95% CI 1.39-2.45; p<0.0001) and overall survival (median 12.6 versus 17.8 months; HR 1.41, 95% CI 1.01-1.97; p=0.04) clearly favoured PGB. In patients with epidermal growth factor receptor mutations (n=32), response rate, progression-free survival and overall survival were not superior with EB. Platinum-based combination chemotherapy remains the standard of care in first-line treatment of unselected NS-NSCLC. Molecular targeted approaches strongly mandate appropriate testing and patient selection.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Cloridrato de Erlotinib/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Desoxicitidina/administração & dosagem , Progressão da Doença , Intervalo Livre de Doença , Receptores ErbB/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Modelos de Riscos Proporcionais , Resultado do Tratamento , Gencitabina
3.
Small ; 10(8): 1566-74, 1442, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24644269

RESUMO

Macroporous TiO2 (anatase) thin films are fabricated by an all low-temperature process in which substrates are dip-coated in suspensions of mixed anatase nanoparticles and polystyrene beads, and the templating agents are removed by ultraviolet (UV) irradiation at a temperature below 50 °C. Scanning electron microscopy (SEM) and Raman spectroscopy show that the templating polymer beads are removed by UV irradiation combined with the photocatalytic activity of TiO2. X-Ray diffraction reveals that nanoparticle growth is negligible in UV irradiated films, while nanoparticle size increases by almost 10 times in calcined films that are prepared for comparison. The macroporous films are prepared on FTO-(fluorine-doped tin oxide) coated glass and ITO (indium tin oxide) coated flexible plastics and thereby used as working electrodes. In both cases, the films are electrochemically addressable, and cyclic voltammetry is consistent with the response of bulk TiO2 for calcined films and of nanoscale-TiO2 for UV-irradiated films.

4.
Eur Radiol ; 24(6): 1376-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24623367

RESUMO

OBJECTIVE: To evaluate diagnostic signs and measurements in the assessment of capsular redundancy in atraumatic multidirectional instability (MDI) of the shoulder on MR arthrography (MR-A) including abduction/external rotation (ABER) images. METHODS: Twenty-one MR-A including ABER position of 20 patients with clinically diagnosed MDI and 17 patients without instability were assessed by three radiologists. On ABER images, presence of a layer of contrast between the humeral head (HH) and the anteroinferior glenohumeral ligament (AIGHL) (crescent sign) and a triangular-shaped space between the HH, AIGHL and glenoid (triangle sign) were evaluated; centring of the HH was measured. Anterosuperior herniation of the rotator interval (RI) capsule and glenoid version were determined on standard imaging planes. RESULTS: The crescent sign had a sensitivity of 57 %/62 %/48 % (observers 1/2/3) and specificity of 100 %/100 %/94 % in the diagnosis of MDI. The triangle sign had a sensitivity of 48 %/57 %/48 % and specificity of 94 %/94 %/100 %. The combination of both signs had a sensitivity of 86 %/90 %/81 % and specificity of 94 %/94 %/94 %. A positive triangle sign was significantly associated with decentring of the HH. Measurements of RI herniation, RI width and glenoid were not significantly different between both groups. CONCLUSIONS: Combined assessment of redundancy signs on ABER position MR-A allows for accurate differentiation between patients with atraumatic MDI and patients with clinically stable shoulders; measurements on standard imaging planes appear inappropriate. KEY POINTS: MR arthrography has the possibility to accurately identify patients with atraumatic MDI. Imaging of the shoulder in abduction and external rotation provides additive information. Capsular enlargement of the shoulder can be diagnosed on MR arthrography.


Assuntos
Bursite/patologia , Instabilidade Articular/patologia , Ligamentos Articulares/patologia , Imageamento por Ressonância Magnética/métodos , Articulação do Ombro/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Úmero/patologia , Cápsula Articular/patologia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Rotação , Sensibilidade e Especificidade , Ombro , Adulto Jovem
5.
Chest ; 164(2): e39-e43, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37558334

RESUMO

CASE PRESENTATION: An 80-year-old man came to the ED with fever, hematuria, and overall discomfort for 1 week. His medical history included a superficial urothelial carcinoma of the bladder for which he was adjunctively treated with intravesical Mycobacterium bovis BCG (bacillus Calmette-Guérin) immunotherapy for several months. The patient was admitted to the hospital and was initially treated with cephalosporins for a suspected complicated urinary tract infection, but his symptoms did not improve. Ten days after the initial admission, the patient developed hypoxemic respiratory failure during an episode of fever and cold chills and was admitted to the ICU.


Assuntos
Vacina BCG , Carcinoma de Células de Transição , Mycobacterium bovis , Insuficiência Respiratória , Neoplasias da Bexiga Urinária , Idoso de 80 Anos ou mais , Humanos , Masculino , Vacina BCG/efeitos adversos , Imunoterapia/efeitos adversos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Neoplasias da Bexiga Urinária/terapia
6.
Radiology ; 264(2): 504-13, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692037

RESUMO

PURPOSE: To retrospectively determine the diagnostic accuracy of magnetic resonance (MR) arthrography of the shoulder in the evaluation of lesions of the biceps pulley and to evaluate previously described and new diagnostic signs. MATERIALS AND METHODS: Institutional review board approval was obtained; the requirement for informed consent was waived. MR arthrograms of 80 consecutive patients (mean age, 34.2 years; 53 male, 27 female) with arthroscopically proved intact or torn pulley systems were assessed for the presence of a pulley lesion by three radiologists who were blinded to arthroscopic results. Criteria evaluated were displacement of the long head of the biceps tendon (LHBT) relative to the subscapularis tendon on oblique sagittal images (displacement sign), medial subluxation of the LHBT on transverse images, nonvisibility or discontinuity of the superior glenohumeral ligament (SGHL), presence of biceps tendinopathy, and rotator cuff tears adjacent to the rotator interval. RESULTS: There were 28 pulley lesions noted at arthroscopy. For observers 1, 2, and 3, respectively: MR arthrography showed a sensitivity of 89%, 86%, and 82% and a specificity of 96%, 98%, and 87% in the detection of pulley lesions. Nonvisibility or discontinuity of the SGHL was sensitive (79%, 89%, and 79%) and specific (83%, 79%, and 75%). With the displacement sign, sensitivity was 86%, 82%, and 75% and specificity was 96%, 98%, 90%. Tendinopathy of the LHBT on oblique sagittal images showed a sensitivity of 93%, 82%, 64%; specificity was 81%, 96%, and 85%. Subluxation of the LHBT was insensitive (36%, 50%, and 64%) but specific (100%, 98%, and 96%). CONCLUSION: MR arthrography is accurate in the detection of pulley lesions; the displacement sign, nonvisibility or discontinuity of the SGHL, and tendinopathy of the LHBT on oblique sagittal images are the most accurate criteria for the detection of pulley lesions.


Assuntos
Instabilidade Articular/diagnóstico , Imageamento por Ressonância Magnética/métodos , Manguito Rotador/patologia , Articulação do Ombro/patologia , Tendinopatia/diagnóstico , Adolescente , Adulto , Idoso , Algoritmos , Artroscopia , Intervalos de Confiança , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
J Neurol Neurosurg Psychiatry ; 83(11): 1093-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22595362

RESUMO

BACKGROUND: Of the newer antiepileptic drugs, lamotrigine (LTG) and levetiracetam (LEV) are popular first choice drugs for epilepsy. The authors compared these drugs with regard to their efficacy and tolerability in the initial monotherapy for epilepsy. METHODS: A randomised, open-label, controlled, parallel group, multicenter trial was conducted to test the superiority of the LEV arm over the LTG arm. The primary endpoint was the rate of seizure-free patients in the first 6 weeks (two-sided Fisher's exact test, α=0.05, intent-to-treat set). Furthermore, efficacy, tolerability and quality of life were evaluated. The authors included 409 patients aged ≥12 years with newly diagnosed focal or generalised epilepsy defined by either two or more unprovoked seizures or one first seizure with high risk for recurrence. Patients were titrated to 2000 mg/day of LEV or 200 mg/day of LTG reached on day 22 or 71, respectively. Two dose adjustments by 500/50 mg were allowed. RESULTS: The proportions of seizure-free patients were 67.5% (LEV) versus 64.0% (LTG) 6 weeks after randomisation (p=0.47), and 45.2% (LEV) versus 47.8% (LTG) during the whole treatment period of 26 weeks. The HR (LEV vs. LTG) for seizure-free time was 0.86 (95% CI, 0.61 to 1.22). Adverse events occurred in 74.5% (LEV) versus 70.6% (LTG) of the patients (p=0.38). Adverse events associated with study discontinuation occurred in 17/204 (LEV) versus 8/201 (LTG) patients (p=0.07). CONCLUSIONS: There were no significant differences with regard to efficacy and tolerability of LEV and LTG in newly diagnosed focal and generalised epilepsy despite more rapid titration in the LEV arm. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier NCT00242606.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Piracetam/análogos & derivados , Triazinas/uso terapêutico , Adolescente , Adulto , Anticonvulsivantes/efeitos adversos , Criança , Diagnóstico Precoce , Feminino , Humanos , Lamotrigina , Levetiracetam , Masculino , Pessoa de Meia-Idade , Piracetam/efeitos adversos , Piracetam/uso terapêutico , Qualidade de Vida , Triazinas/efeitos adversos
8.
Chemistry ; 17(31): 8596-603, 2011 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-21678512

RESUMO

By following a biomimetic design principle, tetravalent scaffolds based on an adamantyl and trisalkylmethyl core structure have been synthesized. These scaffolds have been coupled to three catecholamines, thus resembling the characteristic tripodal recognition motif of many natural metal binders, such as mussel adhesion proteins and siderophores, for example, enterobactin. Besides this tripodal recognition element, our scaffolds provide a fourth position for the conjugation of effector molecules. These effectors can be conjugated through biocompatible conjugation techniques to the scaffold and can be used to tailor the properties of different metal surfaces for a range of applications, for example, in implant engineering. Herein, we describe the synthesis of several tripodal metal binders and their immobilization on TiO(2) surfaces by using a simple dip-coating procedure. Furthermore, we demonstrate the conjugation of our surface binders to the dye eosin Y as an effector molecule by peptide coupling. The resulting surfaces have been analyzed by using ellipsometry, time-of-flight secondary ion mass spectrometry, IR spectroscopy, and contact-angle measurements to confirm the specific loading on TiO(2) films and nanoparticles with our trivalent surface binders. As a proof of concept, we have demonstrated the functionalization of TiO(2) nanoparticles with the eosin Y dye.


Assuntos
Bivalves/química , Fenóis/síntese química , Proteínas/química , Sideróforos/química , Animais , Materiais Biomiméticos/química , Adesão Celular , Enterobactina/química , Amarelo de Eosina-(YS) , Metais/química , Estrutura Molecular , Fenóis/química , Proteínas/metabolismo , Titânio/química
9.
Bone Joint J ; 103-B(11): 1678-1685, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34719276

RESUMO

AIMS: One-stage revision hip arthroplasty for periprosthetic joint infection (PJI) has several advantages; however, resection of the proximal femur might be necessary to achieve higher success rates. We investigated the risk factors for resection and re-revisions, and assessed complications and subsequent re-revisions. METHODS: In this single-centre, case-control study, 57 patients who underwent one-stage revision arthroplasty for PJI of the hip and required resection of the proximal femur between 2009 and 2018 were identified. The control group consisted of 57 patients undergoing one-stage revision without bony resection. Logistic regression analysis was performed to identify any correlation with resection and the risk factors for re-revisions. Rates of all-causes re-revision, reinfection, and instability were compared between groups. RESULTS: Patients who required resection of the proximal femur were found to have a higher all-cause re-revision rate (29.8% vs 10.5%; p = 0.018), largely due to reinfection (15.8% vs 0%; p = 0.003), and dislocation (8.8% vs 10.5%; p = 0.762), and showed higher rate of in-hospital wound haematoma requiring aspiration or evacuation (p = 0.013), and wound revision (p = 0.008). The use of of dual mobility components/constrained liner in the resection group was higher than that of controls (94.7% vs 36.8%; p < 0.001). The presence and removal of additional metal hardware (odds ratio (OR) = 7.2), a sinus tract (OR 4), ten years' time interval between primary implantation and index infection (OR 3.3), and previous hip revision (OR 1.4) increased the risk of proximal femoral resection. A sinus tract (OR 9.2) and postoperative dislocation (OR 281.4) were associated with increased risk of subsequent re-revisions. CONCLUSION: Proximal femoral resection during one-stage revision hip arthroplasty for PJI may be required to reduce the risk of of recurrent or further infection. Patients with additional metalware needing removal or transcortical sinus tracts and chronic osteomyelitis are particularly at higher risk of needing proximal femoral excision. However, radical resection is associated with higher surgical complications and increased re-revision rates. The use of constrained acetabular liners and dual mobility components maintained an acceptable dislocation rate. These results, including identified risk factors, may aid in preoperative planning, patient consultation and consent, and intraoperative decision-making. Cite this article: Bone Joint J 2021;103-B(11):1678-1685.


Assuntos
Artroplastia de Quadril/efeitos adversos , Fêmur/cirurgia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Reoperação/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/métodos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
10.
Mult Scler ; 16(6): 749-53, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20453014

RESUMO

Progressive multifocal leucoencephalopathy has become a growing concern in natalizumab-treated multiple sclerosis patients. Here, we describe a 35-year-old patient who was treated with 34 infusions of natalizumab before complaining about visual deterioration. MRI was non-diagnostic and JC virus testing initially was negative. Electroencephalography showed severe slowing of the right hemisphere, and neuropsychological testing revealed right frontal and temporal deficits. The diagnosis of progressive multifocal leucoencephalopathy was established 2 months later by typical MRI presentation and detection of JC virus DNA in the cerebrospinal fluid. Functional neurological deficits may precede imaging features and should prompt early consideration of progressive multifocal leucoencephalopathy.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Vírus JC/genética , Leucoencefalopatia Multifocal Progressiva/etiologia , Leucoencefalopatia Multifocal Progressiva/virologia , Esclerose Múltipla/terapia , Adulto , Anticorpos Monoclonais Humanizados , Encéfalo/patologia , Encéfalo/virologia , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Leucoencefalopatia Multifocal Progressiva/patologia , Imageamento por Ressonância Magnética , Esclerose Múltipla/patologia , Esclerose Múltipla/virologia , Natalizumab
11.
Graefes Arch Clin Exp Ophthalmol ; 248(7): 1019-27, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20130899

RESUMO

PURPOSE: To report the 6-month results of a new method of refractive correction, femtosecond lenticule extraction (FLEx), and the preliminary outcomes in the first 108 eyes. METHODS: In this prospective study, a flap and a lenticule of intrastromal corneal tissue were cut simultaneously using a femtosecond laser. Thereafter, the lenticule was removed manually and the flap repositioned. One hundred and seven of 108 myopic eyes of 56 patients in the treatment group completed the final 6 months of follow-up. The patients' mean age was 35 years. The preoperative mean spherical equivalent (SE) was -4.59 +/- 1.3 diopters (D). The uncorrected visual acuity and the best spectacle-corrected visual acuity after 6 months, objective and manifest refractions, results of slit-lamp examination, the side effects, and the responses to a questionnaire are reported. RESULTS: Six months postoperatively, the mean SE was -0.19 +/- 0.47 D; 98.1% of treated eyes were within +/-1.0 D, and 74.8% of eyes within +/-0.5 D of the intended correction. Eight (7.4%) of 108 eyes lost one line of Snellen VA, one (0.9%) eye lost two Snellen lines, 46 eyes (43%) gained one line, ten eyes (9.3%) gained two Snellen lines, and the VA remained unchanged in 42 (39.3%) eyes. The patient responses to a standardized questionnaire indicated that 97.1% of patients were satisfied with the obtained results and would undergo the procedure again. CONCLUSION: FLEx appears to be a safe and promising corneal refractive procedure for correcting myopia.


Assuntos
Substância Própria/cirurgia , Cirurgia da Córnea a Laser/métodos , Miopia/cirurgia , Acuidade Visual , Adulto , Astigmatismo/cirurgia , Seguimentos , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Refração Ocular , Retalhos Cirúrgicos , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
12.
Eur Arch Otorhinolaryngol ; 266(8): 1291-300, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18972123

RESUMO

A prospective multicenter phase-II trial (12 centers) was performed by the German larynx organ preservation group (DeLOS) to evaluate the effect of induction chemotherapy (ICHT) with paclitaxel/cisplatin (TP), followed by accelerated-hyperfractionated (concomitant boost) radiotherapy (RT) in responders. The trial was focused on larynx preservation, tumor control, survival, salvage surgery and late toxicity in patients with advanced larynx/hypopharynx carcinoma eligible for total laryngectomy (LE). Seventy-one patients (40 larynx, 87.5% St. III, IV; 31 hypopharynx, 93.4% St. III, IV) were enrolled into the study and treated with ICHT (200 mg/m(2) paclitaxel, 100 mg/m(2) cisplatin; day 1, 22) according to the DeLOS protocol. Patients with complete or partial tumor response proceeded to RT (69.9 Gy in 5.5 weeks). Non-responders received a LE followed by postoperative RT (56-70 Gy in 5.5-7 weeks). The response rate to ICHT for larynx cancer was 69.6% (7.1% complete, 62.5% partial response) and for hypopharyngeal cancer was 84.3% (6.9% complete, 77.4% partial response). Overall survival after 36 months was 60.3% (95% CI, 48.4-72.2%), after 42 months was 56.5% (95% CI, 44.2-68.8%). Laryngectomy-free survival was as follows: after 36 months, 43.0% (95% CI, 30.9-55.0%); after 42 months, 41.3% (95% CI, 29.3-53.3%). Both parameters did not show different outcomes after distinguishing larynx from hypopharynx. LE was indicated in 15 non-responders after ICHT. Five of the 15 non-responders refused the laryngectomy. Two of the five received RT instead and had no evidence of disease 42 months after RT. Late toxicity (dysphagia III, IV LENT SOMA score in laryngectomy-free survivors: after 6 months, 1.8%; 12 months, 11.4%; 18 months, 14.5%; 24 months, 8.1%; 36 months, 16%) and salvage surgery (4 pharyngocutaneous fistulas in 27 operations) were tolerable. In a large portion of patients eligible for LE, the larynx could be preserved with satisfying functional outcome. Good responders after ICHT had also a good general outcome with relatively rare severe late toxicities. Due to a slight increase of relevant late dysphagia, functional outcome regarding swallowing and tracheotomy free breathing should be more focused in future larynx organ preservation trials.


Assuntos
Cisplatino/administração & dosagem , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Laríngeas/tratamento farmacológico , Laringe/efeitos da radiação , Paclitaxel/administração & dosagem , Adulto , Idoso , Antineoplásicos/administração & dosagem , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Laringe/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Resultado do Tratamento
13.
Radiother Oncol ; 89(1): 33-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18621428

RESUMO

PURPOSE: This prospective phase II study was undertaken to assess the feasibility of a larynx preservation protocol with simultaneous radiochemotherapy. PATIENTS AND METHODS: Between 3/1998 and 10/2000, 42 patients with moderately advanced cancer of the larynx (n=25) and hypopharynx (n=17) eligible for total laryngectomy (LE) were treated in a prospective larynx preservation study. The study protocol scheduled 66Gy in 5 weeks using a concomitant boost technique and 70mg/m(2) Carboplatin on days 1-5 in weeks 1 and 5. RESULTS: The median follow-up time of the censored study patients was 41 months (9-95 months). The 5-year overall survival was 0.66 (95% CI 0.48-0.84), the 5-year laryngectomy-free survival 0.60 (95% CI 0.42-0.78), and the laryngeal preservation rate at 5 years 0.67 (95% CI 0.49-0.85). Cox multivariate regression analysis showed the total tumor volume to be the only statistically significant factor on locoregional failure-free survival. Six of 23 tumor-free long-term survivors received a tracheotomy because of late laryngeal toxicity associated with dysphagia 30-79 months after radiochemotherapy. CONCLUSIONS: Due to the late laryngeal toxicity observed the value of this regimen for larynx preservation is limited.


Assuntos
Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/radioterapia , Adulto , Idoso , Terapia Combinada , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Dosagem Radioterapêutica , Taxa de Sobrevida , Resultado do Tratamento
14.
J Nucl Med ; 58(1): 129-137, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27469356

RESUMO

O-(2-18F-fluoroethyl)-l-tyrosine (18F-FET) PET is a well-established method increasingly used for diagnosis, treatment planning, and monitoring in gliomas. Epileptic activity, frequently occurring in glioma patients, can influence MRI findings. Whether seizures also affect 18F-FET PET imaging is currently unknown. The aim of this retrospective analysis was to investigate the brain amino acid metabolism during epileptic seizures by 18F-FET PET and to elucidate the pathophysiologic background. METHODS: Ten patients with 11 episodes of serial seizures or status epilepticus, who underwent MRI and 18F-FET PET, were studied. The main diagnosis was glioma World Health Organization grade II-IV (n = 8); 2 patients suffered from nonneoplastic diseases. Immunohistochemical assessment of LAT1/LAT2/CD98 amino acid transporters was performed in seizure-affected cortex (n = 2) and compared with glioma tissues (n = 3). RESULTS: All patients exhibited increased seizure-associated strict gyral 18F-FET uptake, which was reversible in follow-up studies or negative shortly before and without any histologic or clinical signs of tumor recurrence. 18F-FET uptake corresponded to structural MRI changes, compatible with cortical vasogenic and cytotoxic edema, partial contrast enhancement, and hyperperfusion. Patients with prolonged postictal symptoms lasting up to 8 wk displayed intensive and widespread (≥ 1 lobe) cortical 18F-FET uptake. LAT1/LAT2/CD98 was strongly expressed in neurons and endothelium of seizure-affected brains and less in reactive astrocytosis. CONCLUSION: Seizure activity, in particular status epilepticus, increases cerebral amino acid transport with a strict gyral 18F-FET uptake pattern. Such periictal pseudoprogression represents a potential pitfall of 18F-FET PET and may mimic brain tumor. Our data also indicate a seizure-induced upregulation of neuronal, endothelial, and less astroglial LAT1/LAT2/CD98 amino acid transporter expression.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Aminoácidos/metabolismo , Epilepsia/diagnóstico por imagem , Epilepsia/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Tirosina/análogos & derivados , Adulto , Idoso , Transporte Biológico Ativo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tirosina/farmacocinética
15.
IEEE Trans Neural Syst Rehabil Eng ; 14(2): 153-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16792282

RESUMO

A brain-computer interface (BCI) is a system that allows its users to control external devices with brain activity. Although the proof-of-concept was given decades ago, the reliable translation of user intent into device control commands is still a major challenge. Success requires the effective interaction of two adaptive controllers: the user's brain, which produces brain activity that encodes intent, and the BCI system, which translates that activity into device control commands. In order to facilitate this interaction, many laboratories are exploring a variety of signal analysis techniques to improve the adaptation of the BCI system to the user. In the literature, many machine learning and pattern classification algorithms have been reported to give impressive results when applied to BCI data in offline analyses. However, it is more difficult to evaluate their relative value for actual online use. BCI data competitions have been organized to provide objective formal evaluations of alternative methods. Prompted by the great interest in the first two BCI Competitions, we organized the third BCI Competition to address several of the most difficult and important analysis problems in BCI research. The paper describes the data sets that were provided to the competitors and gives an overview of the results.


Assuntos
Algoritmos , Encéfalo/fisiologia , Auxiliares de Comunicação para Pessoas com Deficiência , Eletroencefalografia/métodos , Validação de Programas de Computador , Avaliação da Tecnologia Biomédica/métodos , Interface Usuário-Computador , Bases de Dados Factuais , Potenciais Evocados/fisiologia , Humanos , Doenças Neuromusculares/reabilitação
16.
IEEE Trans Neural Syst Rehabil Eng ; 14(2): 183-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16792289

RESUMO

We summarize results from a series of related studies that aim to develop a motor-imagery-based brain-computer interface using a single recording session of electroencephalogram (EEG) or electrocorticogram (ECoG) signals for each subject. We apply the same experimental and analytical methods to 11 nonparalysed subjects (eight EEG, three ECoG), and to five paralyzed subjects (four EEG, one ECoG) who had been unable to communicate for some time. While it was relatively easy to obtain classifiable signals quickly from most of the nonparalyzed subjects, it proved impossible to classify the signals obtained from the paralyzed patients by the same methods. This highlights the fact that though certain BCI paradigms may work well with healthy subjects, this does not necessarily indicate success with the target user group. We outline possible reasons for this failure to transfer.


Assuntos
Algoritmos , Inteligência Artificial , Eletroencefalografia/métodos , Potenciais Evocados , Paralisia/fisiopatologia , Reconhecimento Automatizado de Padrão/métodos , Interface Usuário-Computador , Análise por Conglomerados , Capacitação de Usuário de Computador/métodos , Feminino , Humanos , Imaginação , Masculino , Pessoa de Meia-Idade , Paralisia/reabilitação
17.
IEEE Trans Biomed Eng ; 51(6): 1003-10, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15188871

RESUMO

Designing a brain computer interface (BCI) system one can choose from a variety of features that may be useful for classifying brain activity during a mental task. For the special case of classifying electroencephalogram (EEG) signals we propose the usage of the state of the art feature selection algorithms Recursive Feature Elimination and Zero-Norm Optimization which are based on the training of support vector machines (SVM). These algorithms can provide more accurate solutions than standard filter methods for feature selection. We adapt the methods for the purpose of selecting EEG channels. For a motor imagery paradigm we show that the number of used channels can be reduced significantly without increasing the classification error. The resulting best channels agree well with the expected underlying cortical activity patterns during the mental tasks. Furthermore we show how time dependent task specific information can be visualized.


Assuntos
Algoritmos , Inteligência Artificial , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potencial Evocado Motor/fisiologia , Interface Usuário-Computador , Análise por Conglomerados , Mãos/fisiologia , Humanos , Masculino , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
IEEE Trans Biomed Eng ; 51(6): 1044-51, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15188876

RESUMO

Interest in developing a new method of man-to-machine communication--a brain-computer interface (BCI)--has grown steadily over the past few decades. BCIs create a new communication channel between the brain and an output device by bypassing conventional motor output pathways of nerves and muscles. These systems use signals recorded from the scalp, the surface of the cortex, or from inside the brain to enable users to control a variety of applications including simple word-processing software and orthotics. BCI technology could therefore provide a new communication and control option for individuals who cannot otherwise express their wishes to the outside world. Signal processing and classification methods are essential tools in the development of improved BCI technology. We organized the BCI Competition 2003 to evaluate the current state of the art of these tools. Four laboratories well versed in EEG-based BCI research provided six data sets in a documented format. We made these data sets (i.e., labeled training sets and unlabeled test sets) and their descriptions available on the Internet. The goal in the competition was to maximize the performance measure for the test labels. Researchers worldwide tested their algorithms and competed for the best classification results. This paper describes the six data sets and the results and function of the most successful algorithms.


Assuntos
Algoritmos , Esclerose Lateral Amiotrófica/fisiopatologia , Inteligência Artificial , Encéfalo , Eletroencefalografia/métodos , Potenciais Evocados , Interface Usuário-Computador , Adulto , Cognição , Bases de Dados Factuais , Eletroencefalografia/classificação , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
IEEE Trans Pattern Anal Mach Intell ; 26(12): 1645-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15573825

RESUMO

For certain databases and classification tasks, analyzing images based region features instead of image features results in more accurate classifications. We introduce eigenregions, which are geometrical features that encompass area, location, and shape properties of an image region, even if the region is spatially incoherent. Eigenregions are calculated using principal component analysis (PCA). On a database of 77,000 different regions obtained through the segmentation of 13,500 real-scene photographic images taken by nonprofessionals, eigenregions improved the detection of localized image classes by a noticeable amount. Additionally, eigenregions allow us to prove that the largest variance in natural image region geometry is due to its area and not to shape or position.

20.
Science ; 343(6167): 174-8, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24385606

RESUMO

Pine Island Glacier has thinned and accelerated over recent decades, significantly contributing to global sea-level rise. Increased oceanic melting of its ice shelf is thought to have triggered those changes. Observations and numerical modeling reveal large fluctuations in the ocean heat available in the adjacent bay and enhanced sensitivity of ice-shelf melting to water temperatures at intermediate depth, as a seabed ridge blocks the deepest and warmest waters from reaching the thickest ice. Oceanic melting decreased by 50% between January 2010 and 2012, with ocean conditions in 2012 partly attributable to atmospheric forcing associated with a strong La Niña event. Both atmospheric variability and local ice shelf and seabed geometry play fundamental roles in determining the response of the Antarctic Ice Sheet to climate.


Assuntos
Mudança Climática , Camada de Gelo , Ilhas , Congelamento
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