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1.
Laryngoscope ; 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33368380

RESUMO

OBJECTIVES/HYPOTHESIS: Injection laryngoplasty of materials for unilateral vocal-fold paralysis has shown various results regarding the long-term stability of the injected material. We evaluated a fibrin-gel based cell suspension with autologous chondrocytes in-vitro and in-vivo as long-term-stable vocal-fold augmentation material in an animal model. STUDY DESIGN: This study compises an in vitro cell-culture part as well as an in vivo animal study with New Zealand White Rabbits. METHODS: In in-vitro experiments, auricular chondrocytes harvested from 24 New Zealand White Rabbits cadavers were cultivated in pellet cultures to evaluate cartilage formation for 4 weeks using long-term-stable fibrin gel as carrier. Injectability and injection volume for the laryngoplasty was determined in-vitro using harvested cadaveric larynxes. In-vivo 24 Rabbits were biopsied for elastic cartilage of the ear and autologous P1 cells were injected lateral of one vocal cord into the paraglottic space suspended in a long-term-stable fibrin gel. Histologic evaluation was performed after 2, 4, 12, and 24 weeks. RESULTS: During 12-week pellet culture, we found extracellular matrix formation and weight-stable cartilage of mature appearance. In-vivo, mature cartilage was found in two larynxes (n = 6) at 4 weeks, in four (n = 6) at 12 weeks, and in five (n = 6) at 24 weeks mostly located in the paraglottic space and sometimes with spurs into the vocalis muscle. Surrounding tissue was often infiltrated with inflammatory cells. Material tended to dislocate through the cricothyroid space into the extraglottic surrounding tissue. CONCLUSIONS: A cell-based approach with chondrocytes for permanent vocal-fold augmentation has not previously been reported. We have achieved the formation of structurally mature cartilage in the paraglottic space, but this is accompanied by difficulties with dislocated material, deformation of the augmentation, and inflammation. LEVEL OF EVIDENCE: N/A Laryngoscope, 2020.

2.
PLoS One ; 15(9): e0237501, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877418

RESUMO

PURPOSE: The concept of dysphagia/aspiration-related structures (DARS) was developed against the background of severe late side effects of radiotherapy (RT) for head and neck cancer (HNC). DARS can be delineated on CT scans, but with a better morphological discrimination on magnetic resonance imaging (MRI). Swallowing function was analyzed by use of patient charts and prospective investigations and questionnaires. METHOD: Seventeen HNC patients treated with intensity-modulated radiotherapy (IMRT) ± chemotherapy between 5/2012 - 8/2015 were included. Planning CT (computed tomography) scans and MRIs (magnetic resonance imaging) prior, during 40 Gray (Gy) radiotherapy and posttreatment were available and co-registered to delineate DARS. The RT dose of each DARS was calculated. Five patients were investigated posttreatment for swallowing function and assessed by means of various questionnaires for quality of life (QoL), swallowing, and voice function. RESULTS: By retrospective comparison of DARS volume, a significant change in four of eight DARS was detected over time. Three increased and one diminished. The risk of posttreatment dysphagia rose by every 1Gy above the mean dose (D mean) of RT to DARS. 7.5 was the risk factor for dysphagia in the first 6 months, reducing to 4.7 for months 6-12 posttreatment. For all five patients of the prospective part of swallowing investigations, a function disturbance was detected. These results were in contrast to the self-assessment of patients by questionnaires. There was neither a dose dependency of D mean DARS volume changes over time nor of dysphonia and no correlation between volume changes, dysphagia or dysphonia. CONCLUSION: Delineation of DARS on MRI co-registered to planning CT gave the opportunity to differentiate morphology better than by CT alone. Due to the small number of patients with complete MRI scans over time, we failed to detect a dose dependency of DARS and swallowing and voice disorder posttreatment.


Assuntos
Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/radioterapia , Imagem por Ressonância Magnética , Sucção , Tomografia Computadorizada por Raios X , Adulto , Idoso , Deglutição , Transtornos de Deglutição/fisiopatologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários , Voz , Adulto Jovem
3.
Biochem Soc Trans ; 48(4): 1473-1492, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32830854

RESUMO

Membrane proteins (MPs) are the gatekeepers between different biological compartments separated by lipid bilayers. Being receptors, channels, transporters, or primary pumps, they fulfill a wide variety of cellular functions and their importance is reflected in the increasing number of drugs that target MPs. Functional studies of MPs within a native cellular context, however, is difficult due to the innate complexity of the densely packed membranes. Over the past decades, detergent-based extraction and purification of MPs and their reconstitution into lipid mimetic systems has been a very powerful tool to simplify the experimental system. In this review, we focus on proteoliposomes that have become an indispensable experimental system for enzymes with a vectorial function, including many of the here described energy transducing MPs. We first address long standing questions on the difficulty of successful reconstitution and controlled orientation of MPs into liposomes. A special emphasis is given on coreconstitution of several MPs into the same bilayer. Second, we discuss recent progress in the development of fluorescent dyes that offer sensitive detection with high temporal resolution. Finally, we briefly cover the use of giant unilamellar vesicles for the investigation of complex enzymatic cascades, a very promising experimental tool considering our increasing knowledge of the interplay of different cellular components.

5.
J Voice ; 34(5): 807.e1-807.e9, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30876720

RESUMO

INTRODUCTION: Laryngeal and pharyngeal activity during inner singing is discussed in the context of vocal hygiene. Inner singing is defined as imagined singing, reading music silently, and listening to vocal music. When vocal rest is prescribed, doctors, speech therapists, and voice pedagogues recommend avoiding listening to music or reading music silently, since it is suggested that inner singing unconsciously influences the glottis, and thus moves the vocal folds involuntarily. The aim of this study was to compare the degree to which involuntary laryngeal and/or pharyngeal activity occur during inner singing, inner speech, and at rest, and to evaluate if current recommendations concerning vocal hygiene are still reasonable. MATERIAL AND METHOD: Thirty vocally healthy participants were examined transnasally with a flexible videoendoscope. The sample consisted of 10 nonsingers, 10 lay singers, and 10 professional singers. Participants were examined during five tasks including rest, silent reading, imagining a melody, listening to music, and reading music. Two medical doctors specializing in phoniatrics analyzed the videos both qualitatively and quantitatively. RESULTS: During the endoscopic examination, the raters identified movements at the base of the tongue, the posterior and lateral pharynx wall, the arytenoid cartilage, and the vocal folds. The inner singing tasks showed significantly more laryngeal movements as well as significantly more glottal closures than the control tasks (at rest, silent reading). Pharyngeal structures did not show an increase in activity during inner singing. These findings were independent of the level of proficiency in singing. CONCLUSION: When total vocal rest is prescribed, patients should also be advised to avoid music imagination. Still, further research is needed to survey in detail the actual effects of these involuntary movements during inner singing on the regeneration process of vocal fold healing.

6.
J Voice ; 34(3): 335-345, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30448316

RESUMO

The study assessed 30 nonprofessional singers to evaluate the effects of vocal tract shape adjustment via increased resonance toward an externally applied sinusoidal frequency of 900 Hz without phonation. The amplification of the sound wave was used as biofeedback signal and the intensity and the formant position of the basic vowels /a/, /e/, /i/, /o/, and /u/ were compared before and after a vocal tract adjustment period. After the adjustment period, the intensities for all vowels increased and the measured changes correlated with the participants' self-perception.The diferences between the second formant position of the vowels and the applied frequency influences the changes in amplitude and in formant frequencies. The most significant changes in formant frequency occurred with vowels that did not include a formant frequency of 900 Hz, while the increase in amplitude was the strongest for vowels with a formant frequency of about 900 Hz.

7.
Laryngorhinootologie ; 98(10): 695-700, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31610597

RESUMO

BACKGROUND: In Germany, about 5 million people of all ages suffer from dysphagia. Due to demographic change and improved medical care, the incidence of swallowing disorders is expected to increase. Dysphagia is associated with an increased morbidity and mortality and leads to a considerable financial burden on the health systems. The two most common causes of dysphagia are neurological disorders and head and neck cancer. Diagnostics and therapy have developed continuously over the past decades. In particular, the flexible endoscopic evaluation of swallowing (FEES) has become an established part of dysphagia diagnostics. RESULTS: The certificate "Diagnostics and Therapy of Oropharyngeal Dysphagia, incl. FEES" was developed by the German Society for Phoniatrics and Pedaudiology (DGPP) and the German Society for Otolaryngology, Head and Neck Surgery (DGHNO KHC) in cooperation with the German Professional Association for Phoniatrics and Pedaudiology and the German Professional Association of Otolaryngologists.It consists of three parts: the modules (A, B and C), the indirect supervision and a practical examination. Structure, detailed contents and requirements for obtaining the certificate are described in the following article. The qualification of the lecturers and auditors are also defined. CONCLUSION: The systematic training serves the quality assurance and establishment of standards in the diagnostics and therapy of oropharyngeal dysphagia in the area of phoniatrics and ear, nose and throat medicine.


Assuntos
Transtornos de Deglutição , Currículo , Deglutição , Alemanha , Humanos , Otolaringologia
8.
J Voice ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31488316

RESUMO

OBJECTIVE: The purpose of the study was to implement a cross-validation and adaption of the Vocal Fatigue Index (VFI) in German language. METHODS: The translation process for the German version (GV) of the VFI passed through three steps of translation before a final version was completed. Study subjects included 100 vocally healthy subjects and 101 voice-disordered subjects with various types of dysphonia. The internal consistency was determined using Cronbach's alpha (cron α) and the item-total analysis. Test-retest reliability was measured with the Pearson correlation coefficient. To assess the validity, the independent sample t test, the receiver-operating characteristic curve, the likelihood ratios, and Youden Index were used. RESULTS: The internal consistency across all three domains were good (#1: cron α = 0.945, #2: cron α = 0.904, and #3: cron α = 0.871) and no item of the GV of the VFI had to be deleted for further analysis relating to the item-total analysis. The test-retest reliability was high to very high (r = 0.86-0.93). Significant higher scores were revealed in voice-disordered subjects in comparison with vocally healthy subjects in all three domains (all Pvalues <0.01). Thresholds for the three domains of the GV of the VFI were determined at ≥15.5 (76.2% sensitivity and 90.0% specificity) for #1, ≥2.5 (71.5% sensitivity and 81.0% specificity) for #2, and ≤7.5 (50.5% sensitivity and 80.0% specificity) for #3. CONCLUSIONS: It can be considered that the VFI is a valid and reliable tool identifying vocal fatigue symptoms and its severity in the German-speaking population.

9.
Laryngorhinootologie ; 98(10): 701-707, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31378851

RESUMO

AIM: To evaluate ultrasonographic hypoechoic lesions (HEL) of the head and neck region to predict their entity and plan surgery. METHODS: Patients with HEL were included that were further analysed by B-mode ultrasound (US), colour-coded duplex sonography (CDS), contrast enhanced US (CEUS), and strain elastography (SE). RESULTS: 184 patients were included. Level VIII, II, and I were affected frequently with 103, 40, and 21 HEL. The cohort comprised 40 lymph node disorders, 101 salivary gland diseases, 31 cystic lesions, and 12 other rarer entities. HEL in level II were significantly larger than in level I and VIII (p < 0.001). HEL in level VI showed less vascularisation than in level VIII in CDS (p < 0.01). There were no differences in B-mode criteria, SE, or CEUS between HEL in the different neck levels. Patients with cystic lesions were significantly younger than patients with metastases or Warthin's tumours (p = 0.026, 0.028). Pleomorphic adenomas were significantly smaller than cystic lesions (p < 0.0006), lymphomas (p = 0.026), metastases (p = 0.0003), or Warthin's tumours (p = 0.034). In CDS and CEUS, cystic lesions showed significantly less vascularisation and perfusion than lymphomas (p = 0.014) and Warthin's tumours (p < 0.0001), while pleomorphic adenomas were stiffer than cystic lesions in SE (p = 0.0006). CONCLUSION: Predicting lesion's entity is still challenging. The combination of different ultrasonographic criteria helped selecting patients that needed intraoperative fresh frozen section with possible extended surgery and profited from intraoperative nerve monitoring.


Assuntos
Adenolinfoma , Adenoma Pleomorfo , Técnicas de Imagem por Elasticidade , Neoplasias Parotídeas , Ultrassonografia , Humanos , Neovascularização Patológica
10.
Sci Rep ; 9(1): 4766, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886219

RESUMO

The cytochrome bo3 quinol oxidase from Vitreoscilla (vbo3) catalyses oxidation of ubiquinol and reduction of O2 to H2O. Data from earlier studies suggested that the free energy released in this reaction is used to pump sodium ions instead of protons across a membrane. Here, we have studied the functional properties of heterologously expressed vbo3 with a variety of methods. (i) Following oxygen consumption with a Clark-type electrode, we did not observe a measurable effect of Na+ on the oxidase activity of purified vbo3 solubilized in detergent or reconstituted in liposomes. (ii) Using fluorescent dyes, we find that vbo3 does not pump Na+ ions, but H+ across the membrane, and that H+-pumping is not influenced by the presence of Na+. (iii) Using an oxygen pulse method, it was found that 2 H+/e- are ejected from proteoliposomes, in agreement with the values found for the H+-pumping bo3 oxidase of Escherichia coli (ecbo3). This coincides with the interpretation that 1 H+/e- is pumped across the membrane and 1 H+/e- is released during quinol oxidation. (iv) When the electron transfer kinetics of vbo3 upon reaction with oxygen were followed in single turnover experiments, a similar sequence of reaction steps was observed as reported for the E. coli enzyme and none of these reactions was notably affected by the presence of Na+. Overall the data show that vbo3 is a proton pumping terminal oxidase, behaving similarly to the Escherichia coli bo3 quinol oxidase.


Assuntos
Transporte de Elétrons/fisiologia , Oxirredutases/metabolismo , Bombas de Próton/metabolismo , Sódio/metabolismo , Vitreoscilla/metabolismo , Grupo dos Citocromos b/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Transporte de Íons , Oxirredução , Oxigênio/metabolismo , Consumo de Oxigênio/fisiologia , Prótons , Vitreoscilla/enzimologia
11.
J Voice ; 33(4): 482-489, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29454552

RESUMO

In this study, an adjustment of the vocal tract shape toward selected sound waves in the frequency range of the first and second formants without phonation is discussed. The sound waves of a loudspeaker in front of the open mouth and amplified by the vocal tract are used as biofeedback signals. It is shown that the resonance amplification of the vocal tract complies with the concept of forced oscillation, with the driver being the sound source and the resonator being the vocal tract. An adjustment toward increased amplification via vocal tract resonance can be related to smaller bandwidths and lower damping. Furthermore, the applied adjustment frequencies are preserved as vocal tract resonances during exhalation and even phonation. This novel form of biofeedback might enrich standard voice training procedures by exercises without phonation.


Assuntos
Acústica , Biorretroalimentação Psicológica , Fonação , Prega Vocal/fisiologia , Qualidade da Voz , Treinamento da Voz , Análise de Fourier , Humanos , Pressão , Estudos de Caso Único como Assunto , Espectrografia do Som , Fatores de Tempo , Vibração
12.
Sci Rep ; 6: 34098, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27682138

RESUMO

Complex III in C. glutamicum has an unusual di-heme cyt. c1 and it co-purifies with complex IV in a supercomplex. Here, we investigated the kinetics of electron transfer within this supercomplex and in the cyt. aa3 alone (cyt. bc1 was removed genetically). In the reaction of the reduced cyt. aa3 with O2, we identified the same sequence of events as with other A-type oxidases. However, even though this reaction is associated with proton uptake, no pH dependence was observed in the kinetics. For the cyt. bc1-cyt. aa3 supercomplex, we observed that electrons from the c-hemes were transferred to CuA with time constants 0.1-1 ms. The b-hemes were oxidized with a time constant of 6.5 ms, indicating that this electron transfer is rate-limiting for the overall quinol oxidation/O2 reduction activity (~210 e-/s). Furthermore, electron transfer from externally added cyt. c to cyt. aa3 was significantly faster upon removal of cyt. bc1 from the supercomplex, suggesting that one of the c-hemes occupies a position near CuA. In conclusion, isolation of the III-IV-supercomplex allowed us to investigate the kinetics of electron transfer from the b-hemes, via the di-heme cyt. c1 and heme a to the heme a3-CuB catalytic site of cyt. aa3.

13.
World J Gastroenterol ; 21(3): 982-7, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25624734

RESUMO

AIM: To determine the laryngeal H+K+-ATPase and pharyngeal pH in patients with laryngopharyngeal reflux (LPR)-symptoms as well as to assess the symptom scores during PPI therapy. METHODS: Endoscopy was performed to exclude neoplasia and to collect biopsies from the posterior cricoid area (immunohistochemistry and PCR analysis). Immunohistochemical staining was performed with monoclonal mouse antibodies against human H+K+-ATPase. Quantitative real-time RT-PCR for each of the H+K+-ATPase subunits was performed. The pH values were assessed in the aerosolized environment of the oropharynx (DxpH Catheter) and compared to a subsequently applied combined pH/MII measurement. RESULTS: Twenty patients with LPR symptoms were included. In only one patient, the laryngeal H+K+-ATPase was verified by immunohistochemical staining. In another patient, real-time RT-PCR for each H+K+-ATPase subunit was positive. Fourteen out of twenty patients had pathological results in DxpH, and 6/20 patients had pathological results in pH/MII. Four patients had pathological results in both functional tests. Nine out of twenty patients responded to PPIs. CONCLUSION: The laryngeal H+K+-ATPase can only be sporadically detected in patients with LPR symptoms and is unlikely to cause the LPR symptoms. Alternative hypotheses for the pathomechanism are needed. The role of pharyngeal pH-metry remains unclear and its use can only be recommended for patients in a research study setting.


Assuntos
ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Refluxo Laringofaríngeo/diagnóstico , Laringe/enzimologia , Monitorização Fisiológica/métodos , Faringe/metabolismo , Adulto , Idoso , Biópsia , Feminino , ATPase Trocadora de Hidrogênio-Potássio/genética , Humanos , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Refluxo Laringofaríngeo/tratamento farmacológico , Refluxo Laringofaríngeo/enzimologia , Refluxo Laringofaríngeo/genética , Refluxo Laringofaríngeo/fisiopatologia , Laringoscopia , Laringe/efeitos dos fármacos , Laringe/fisiopatologia , Masculino , Pessoa de Meia-Idade , Faringe/efeitos dos fármacos , Faringe/fisiopatologia , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Resultado do Tratamento
14.
J Gastrointest Surg ; 16(6): 1096-101, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22450948

RESUMO

OBJECTIVE: Diagnosis of laryngopharyngeal reflux (LPR) is still challenging. Recently a diagnostic device for pH values in the aerosolized environment of the pharynx has been introduced (Dx-pH). We evaluated results of Dx-pH with objective criteria of pH/impedance monitoring (MII) and subjective reflux scoring systems and assessed day-to-day variability. DESIGN: This study makes use of a prospective single-center trial. Thirty patients with suspected LPR were analyzed. Upper endoscopic examination, manometry, phoniatric examination, and reflux scores were assessed. Dx-pH was performed on two consecutive days, first in combination with MII and second as single measurement. Thereafter, proton pump inhibitor (PPI) trial was performed. Patients were interviewed about symptom relief after 3 months. RESULTS: There were considerable differences between MII and results on Dx-pH: day 1 (agreement 11 out of 30, kappa 0.137) and day 2 (agreement 14 out of 30, kappa 0.036). Statistically significant differences were detected correlating all single reflux episodes (n = 453) of Dx-pH with MII and vice versa. Furthermore acidic reflux episodes did not result in pH drops of the pharynx. There was a fair agreement between Dx-pH measurements on subsequent days. After follow-up, 3 out of 18 patients with pathological Dx-pH results reported positive response to PPIs, in contrast to 5 out of 6 patients with pathological MII. CONCLUSION: According to our data, acid pharyngeal pH levels detected with Dx-pH are not related to GERD and acid esophageal reflux episodes do not result in pharyngeal pH alterations. Hence, present etiology of LPR needs to be reconsidered since neither mixed nor gas reflux events result in pharyngeal pH alteration. Other acid-producing or retaining factors should be taken into account.


Assuntos
Monitoramento do pH Esofágico , Refluxo Laringofaríngeo/diagnóstico , Faringe/fisiopatologia , Adulto , Idoso , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Impedância Elétrica , Esofagoscopia , Feminino , Seguimentos , Humanos , Concentração de Íons de Hidrogênio , Refluxo Laringofaríngeo/tratamento farmacológico , Refluxo Laringofaríngeo/metabolismo , Masculino , Manometria , Pessoa de Meia-Idade , Faringe/metabolismo , Pressão , Estudos Prospectivos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/uso terapêutico , Curva ROC , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
16.
Emerg Infect Dis ; 15(2): 185-91, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19193261

RESUMO

Children account for an appreciable proportion of total imported malaria cases, yet few studies have quantified these cases, identified trends, or suggested evidence-based prevention strategies for this group of travelers. We therefore sought to identify numbers of cases and deaths, Plasmodium species, place of malaria acquisition, preventive measures used, and national origin of malaria in children. We analyzed retrospective data from Australia, Denmark, France, Germany, Italy, Japan, the Netherlands, Sweden, Switzerland, the United Kingdom, and the United States and data provided by the United Nations World Tourism Organization. During 1992-2002, >17,000 cases of imported malaria in children were reported in 11 countries where malaria is not endemic; most (>70%) had been acquired in Africa. Returning to country of origin to visit friends and relatives was a risk factor. Malaria prevention for children should be a responsibility of healthcare providers and should be subsidized for low-income travelers to high-risk areas.


Assuntos
Países Desenvolvidos , Malária , Plasmodium , Viagem , Adolescente , Animais , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Malária/epidemiologia , Malária/mortalidade , Malária/parasitologia , Malária Falciparum/epidemiologia , Malária Falciparum/mortalidade , Malária Falciparum/parasitologia , Plasmodium/classificação , Plasmodium/isolamento & purificação , Plasmodium falciparum/isolamento & purificação , Vigilância da População/métodos
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