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1.
Ophthalmologie ; 121(7): 554-564, 2024 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-38801461

RESUMO

PURPOSE: In recent years artificial intelligence (AI), as a new segment of computer science, has also become increasingly more important in medicine. The aim of this project was to investigate whether the current version of ChatGPT (ChatGPT 4.0) is able to answer open questions that could be asked in the context of a German board examination in ophthalmology. METHODS: After excluding image-based questions, 10 questions from 15 different chapters/topics were selected from the textbook 1000 questions in ophthalmology (1000 Fragen Augenheilkunde 2nd edition, 2014). ChatGPT was instructed by means of a so-called prompt to assume the role of a board certified ophthalmologist and to concentrate on the essentials when answering. A human expert with considerable expertise in the respective topic, evaluated the answers regarding their correctness, relevance and internal coherence. Additionally, the overall performance was rated by school grades and assessed whether the answers would have been sufficient to pass the ophthalmology board examination. RESULTS: The ChatGPT would have passed the board examination in 12 out of 15 topics. The overall performance, however, was limited with only 53.3% completely correct answers. While the correctness of the results in the different topics was highly variable (uveitis and lens/cataract 100%; optics and refraction 20%), the answers always had a high thematic fit (70%) and internal coherence (71%). CONCLUSION: The fact that ChatGPT 4.0 would have passed the specialist examination in 12 out of 15 topics is remarkable considering the fact that this AI was not specifically trained for medical questions; however, there is a considerable performance variability between the topics, with some serious shortcomings that currently rule out its safe use in clinical practice.


Assuntos
Avaliação Educacional , Oftalmologia , Conselhos de Especialidade Profissional , Oftalmologia/educação , Avaliação Educacional/métodos , Avaliação Educacional/normas , Alemanha , Humanos , Competência Clínica/normas , Certificação , Inteligência Artificial
2.
Transl Oncol ; 37: 101773, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37666208

RESUMO

INTRODUCTION: Conventional morphologic and volumetric assessment of treatment response is not suitable for adequately assessing responses to targeted cancer therapy. The aim of this study was to evaluate changes in tumor composition after targeted therapy in murine models of breast cancer with differing degrees of malignancy via non-invasive magnetic resonance imaging (MRI). MATERIALS AND METHODS: Mice bearing highly malignant 4T1 tumors or low malignant 67NR tumors were treated with either a combination of two immune checkpoint inhibitors (ICI, anti-PD1 and anti-CTLA-4) or the multi-tyrosine kinase inhibitor sorafenib, following experiments with macrophage-depleting clodronate-loaded liposomes and vessel-stabilizing angiopoietin-1. Mice were imaged on a 9.4 T small animal MRI system with a multiparametric (mp) protocol, comprising T1 and T2 mapping and diffusion-weighted imaging. Tumors were analyzed ex vivo with histology. RESULTS AND DISCUSSIONS: All treatments led to an increase in non-viable areas, but therapy-induced intratumoral changes differed between the two tumor models and the different targeted treatments. While ICI treatment led to intratumoral hemorrhage, sorafenib treatment mainly induced intratumoral necrosis. Treated 4T1 tumors showed increasing and extensive areas of necrosis, in comparison to 67NR tumors with only small, but also increasing, necrotic areas. After either of the applied treatments, intratumoral heterogeneity, was increased in both tumor models, and confirmed ex vivo by histology. Apparent diffusion coefficient with subsequent histogram analysis proved to be the most sensitive MRI sequence. In conclusion, mp MRI enables to assess dedicated therapy-related intratumoral changes and may serve as a biomarker for treatment response assessment.

3.
Anaesthesist ; 68(8): 520-529, 2019 08.
Artigo em Alemão | MEDLINE | ID: mdl-31396674

RESUMO

BACKGROUND: Dipyrone (metamizole) is widely used for perioperative pain management in countries where it is marketed; however, uncertainty exists concerning the safe use of this drug, specifically considering the rare adverse event of an agranulocytosis. METHODS: As evidence from published studies was lacking, an expert panel developed recommendations for the perioperative use of dipyrone. After a formal, structured consensus process, the recommendations were approved by the involved medical societies. RESULTS: The panel agreed that blood cell counts shall not be standard for short-term perioperative use in patients unless they are at risk for neutropenia. The medical staff shall be aware of the symptoms and course of action when agranulocytosis is suspected. Patients shall be informed about the risks and benefits of dipyrone and about potential alternatives. The expert group concluded that dipyrone has a relatively positive risk-benefit ratio compared to other nonopioid analgesics. The group strongly recommended educating patients about the symptoms of agranulocytosis if they have received dipyrone over several days and/or treatment is to be continued after discharge, because agranulocytosis can occur several days after discontinuation of metamizole. Further recommendations refer to the information of the physician taking over the patient's care after discharge and the avoidance of re-exposure in patients having previously suffered from dipyrone-induced agranulocytosis. CONCLUSION: The group's recommendations shall be communicated in order to raise medical staff's and patients' awareness of the appropriate use of dipyrone in the perioperative period.


Assuntos
Dor Aguda/tratamento farmacológico , Agranulocitose/induzido quimicamente , Analgésicos não Narcóticos/uso terapêutico , Dipirona/uso terapêutico , Período Perioperatório , Sociedades Médicas , Analgésicos não Narcóticos/efeitos adversos , Anestesiologia , Dipirona/efeitos adversos , Alemanha , Humanos , Suíça
4.
Chirurg ; 90(8): 652-659, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31359112

RESUMO

BACKGROUND: Dipyrone (metamizole) is widely used for perioperative pain management in countries where it is marketed; however, uncertainty exists concerning the safe use of this drug, specifically considering the rare adverse event of an agranulocytosis. METHODS: As evidence from published studies was lacking, an expert panel developed recommendations for the perioperative use of dipyrone. After a formal, structured consensus process, the recommendations were approved by the involved medical societies. RESULTS: The panel agreed that blood cell counts shall not be standard for short-term perioperative use in patients unless they are at risk for neutropenia. The medical staff shall be aware of the symptoms and course of action when agranulocytosis is suspected. Patients shall be informed about the risks and benefits of dipyrone and about potential alternatives. The expert group concluded that dipyrone has a relatively positive risk-benefit ratio compared to other nonopioid analgesics. The group strongly recommended educating patients about the symptoms of agranulocytosis if they have received dipyrone over several days and/or treatment is to be continued after discharge, because agranulocytosis can occur several days after discontinuation of metamizole. Further recommendations refer to the information of the physician taking over the patient's care after discharge and the avoidance of re-exposure in patients having previously suffered from dipyrone-induced agranulocytosis. CONCLUSION: The group's recommendations shall be communicated in order to raise medical staff's and patients' awareness of the appropriate use of dipyrone in the perioperative period.


Assuntos
Dor Aguda , Anestesiologia , Anti-Inflamatórios não Esteroides , Dipirona , Dor Aguda/tratamento farmacológico , Analgésicos , Anti-Inflamatórios não Esteroides/uso terapêutico , Cuidados Críticos , Dipirona/uso terapêutico , Humanos
5.
Schmerz ; 33(4): 287-294, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31342162

RESUMO

BACKGROUND: Dipyrone (metamizole) is widely used for perioperative pain management in countries where it is marketed; however, uncertainty exists concerning the safe use of this drug, specifically considering the rare adverse event of an agranulocytosis. METHODS: As evidence from published studies was lacking, an expert panel developed recommendations for the perioperative use of dipyrone. After a formal, structured consensus process, the recommendations were approved by the involved medical societies. RESULTS: The panel agreed that blood cell counts shall not be standard for short-term perioperative use in patients unless they are at risk for neutropenia. The medical staff shall be aware of the symptoms and course of action when agranulocytosis is suspected. Patients shall be informed about the risks and benefits of dipyrone and about potential alternatives. The expert group concluded that dipyrone has a relatively positive risk-benefit ratio compared to other nonopioid analgesics. The group strongly recommended educating patients about the symptoms of agranulocytosis if they have received dipyrone over several days and/or treatment is to be continued after discharge, because agranulocytosis can occur several days after discontinuation of metamizole. Further recommendations refer to the information of the physician taking over the patient's care after discharge and the avoidance of re-exposure in patients having previously suffered from dipyrone-induced agranulocytosis. CONCLUSION: The group's recommendations shall be communicated in order to raise medical staff's and patients' awareness of the appropriate use of dipyrone in the perioperative period.


Assuntos
Agranulocitose , Dipirona , Dor Aguda/tratamento farmacológico , Dor Aguda/prevenção & controle , Agranulocitose/induzido quimicamente , Agranulocitose/prevenção & controle , Analgésicos/administração & dosagem , Analgésicos/efeitos adversos , Anestesiologia/normas , Associação , Cuidados Críticos , Dipirona/administração & dosagem , Dipirona/efeitos adversos , Humanos , Período Perioperatório
6.
Ophthalmologe ; 116(9): 879-881, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-30519740

RESUMO

The treatment of congenital glaucoma requires special expertise and often novel surgical approaches. The combined use of a XEN and a Baerveldt implant is an alternative to conventional tube implants and may be less harmful for long-term corneal endothelial damage. If this technique does not provide sufficient long-term control of intraorbital pressure (IOP), a direct implantation of the Baerveldt tube can be easily performed in a second intervention.


Assuntos
Implantes para Drenagem de Glaucoma , Pressão Intraocular
7.
Ophthalmologe ; 115(7): 585-591, 2018 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-29770858

RESUMO

INTRODUCTION: As our population ages and comorbidities rise, ophthalmic surgeons are increasingly faced with patients on anticoagulant therapy or with clotting disorders. The ophthalmic surgeon has to weigh the perioperative risk of haemorrhage when anticoagulation continues against the risk of thromboembolism caused by discontinuation or changing the patient's medication (bridging, switching, cessation). There are currently no guidelines or recommendations. METHODS: A survey was sent to the DOG (German Ophthalmologic Society) divisions and associated surgical organizations to determine the status quo. A questionnaire was sent out and filled out by the different groups of specialists. RESULTS: All four divisions of the DOG and four associated organizations returned completed questionnaires. Surgical interventions were listed that are carried out during anticoagulant therapy without exceptions, as well as interventions that were classified to require medical adjustment. Although the assessments varied, general consensus was achieved regarding interventions not requiring adjustments due to anticoagulants (i. e., intravitreal injection, cataract surgery, laser and corneal operations, simple muscle surgery), and those interventions requiring adjustments in medications (glaucoma operations, complex retina surgery, eye socket surgery, complex surgery of the lid). CONCLUSION: Main result of this survey was the specification of serious bleeding complications which are permanent vision loss and re-operation. They could serve as endpoint parameters for essential future investigations. Nevertheless, this survey makes clear that the decision about an adjustment of anticoagulant medication in ophthalmic surgery is currently made individually and not based on established standards.


Assuntos
Cirurgiões , Tromboembolia , Anticoagulantes , Alemanha , Humanos , Inquéritos e Questionários
8.
Ophthalmologe ; 115(6): 521-523, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29589148

RESUMO

Trabeculectomy is the most proven method for the treatment of open angle glaucoma. The long-term results of this method show an 80% success rate in lowering intraocular pressure over 20 years. The surgical technique is demonstrated in detail with the help of a video of the operation and which is available online. For more than 15 years trabeculectomy has been performed with the use of antifibrotic substances, such as mitomycin C. Long-term treatment with antiglaucoma eyedrops leads to a proven inflammation of the conjunctiva and the ocular surface with an increase in lymphocytes, mast cells, and fibroblasts. Discontinuation of antiglaucoma therapy in turn allows regeneration of the ocular surface. From the knowledge gained from these histopathological studies it has been recommended to stop glaucoma treatment prior to glaucoma surgery and to pretreat the conjunctiva with eyedrops containing cortisone. Administration of nonsteroidal antiphlogistic substances or local steroids to the conjunctiva 4 weeks prior to surgery increases long-term success of the filtering bleb function.


Assuntos
Trabeculectomia , Túnica Conjuntiva , Pressão Intraocular , Mitomicina , Tonometria Ocular , Resultado do Tratamento
9.
Ophthalmologe ; 114(10): 885-889, 2017 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-28676930

RESUMO

Career paths have become very complex and variable in the field of ophthalmology. The common way of ophthalmologists in private practice is still a very popular model, especially with regard to the autonomy which has been missing for years in hospitals. It is still an attractive way but alternative developmental options which appear more exciting and flexible, are on the increase.


Assuntos
Competência Clínica , Educação de Pós-Graduação em Medicina , Internato e Residência , Oftalmologia/educação , Escolha da Profissão , Currículo , Alemanha , Humanos , Prática Privada , Especialização
10.
HNO ; 65(Suppl 2): 130-135, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28477091

RESUMO

BACKGROUND: The HÖRSTAT study conducted in Northwest Germany found hearing impairment in approximately 16% of adults when applying the World Health Organization (WHO) criterion. However, the robustness of extrapolations to a national level might be questioned, as the epidemiological data were collected on a regional level. METHODS: Independently from HÖRSTAT, the "Hearing in Germany" study examined adult hearing in Aalen, a town located in Southwest Germany. Both cross-sectional studies were based on stratified random samples from the general population. The average pure-tone threshold shift at 0.5, 1, 2, and 4 kHz (PTA4), the prevalence of hearing impairment (WHO criterion: PTA4 in the better ear >25), and hearing aid uptake were compared. Data from the Aalen and HÖRSTAT studies were pooled (n = 3105) to extrapolate to the prevalence and the degree of hearing impairment for the years 2015, 2020, and 2025. RESULTS: Both studies yielded very similar results for PTA4. Weighted for official population statistics, the prevalence of hearing impairment according to the WHO criterion is 16.2% in adults, thus affecting 11.1 million persons in Germany. Owing to demographic changes, the prevalence is expected to increase in the medium term by around 1% per 5­year period. With a similar degree of hearing loss, hearing aid provision differs from place to place. CONCLUSION: When adjusted for gender and age to the European Standard Population, the prevalence of hearing impairment observed both in HÖRSTAT and the Aalen sample is considerably lower than reported for international studies. Since the analysis refers to cross-sectional data only, possible cohort effects are not considered in the prevalence projection.


Assuntos
Perda Auditiva/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Audiometria de Tons Puros , Limiar Auditivo , Estudos Transversais , Feminino , Alemanha/epidemiologia , Auxiliares de Audição/estatística & dados numéricos , Perda Auditiva/reabilitação , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos
11.
PLoS One ; 12(5): e0178099, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542372

RESUMO

PURPOSE: To compare two surgical approaches for treating encapsulated blebs after trabeculectomy with mitomycin C, in terms of the development of intraocular pressure and progression of glaucoma in a long-term follow up: 1. bleb needling alone vs. 2. a combined approach of needling with additional transconjunctival scleral flap sutures, to prevent early ocular hypotony. METHODS: Forty-six patients with failing blebs after trabeculectomy with mitomycin C were enrolled in this study. Patients received either needling revision alone (group 1; n = 23) or a combined needling with additional transconjuctival flap sutures, if intraoperatively the intraocular pressure was estimated to be low (group 2; n = 23). Intraocular pressure (IOP), visual acuity, visual fields, and optic nerve head configuration by means of Heidelberg Retina Tomograph (HRT®) were analysed over time. Results from both groups were compared using Mann-Whitney U-test for single timepoints. RESULTS: IOP did not differ significantly between the two groups during follow-up at three months (P = 0.13), six months (P = 0.12), one year (P = 0.92) and two years (P = 0.57) after surgery. Furthermore, there was no significant difference in the course of glaucoma concerning the optic nerve anatomy between the two groups (Rim Area Change in the Moorfields Regression Analysis of HRT®) till two years after surgery (P = 0.289). No functional impairment in visual acuity and visual fields was found in the groups of the study. CONCLUSIONS: Single needling procedure is a standard successful method for restoring the function of encapsulated blebs. Postoperative hypotony represents a possible hazard, which can be minimized by additional transconjunctival flap sutures. Long-term results suggest that this modification is equally effective in lowering the IOP and preventing the progression of glaucoma as the standard needling procedure. To our knowledge this is the first study to investigate the long-term effect of tranconjunctival sutures for the prevention of hypotony.


Assuntos
Vesícula/cirurgia , Trabeculectomia/métodos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Vesícula/tratamento farmacológico , Túnica Conjuntiva/cirurgia , Feminino , Seguimentos , Humanos , Pressão Intraocular/efeitos dos fármacos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Mitomicina/farmacologia , Mitomicina/uso terapêutico , Disco Óptico/fisiologia , Retalhos Cirúrgicos , Tonometria Ocular , Acuidade Visual/fisiologia , Campos Visuais/fisiologia
13.
Nano Lett ; 15(5): 3295-302, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25923841

RESUMO

Strong surface and impurity scattering in III-V semiconductor-based nanowires (NW) degrade the performance of electronic devices, requiring refined concepts for controlling charge carrier conductivity. Here, we demonstrate remote Si delta (δ)-doping of radial GaAs-AlGaAs core-shell NWs that unambiguously exhibit a strongly confined electron gas with enhanced low-temperature field-effect mobilities up to 5 × 10(3) cm(2) V(-1) s(-1). The spatial separation between the high-mobility free electron gas at the NW core-shell interface and the Si dopants in the shell is directly verified by atom probe tomographic (APT) analysis, band-profile calculations, and transport characterization in advanced field-effect transistor (FET) geometries, demonstrating powerful control over the free electron gas density and conductivity. Multigated NW-FETs allow us to spatially resolve channel width- and crystal phase-dependent variations in electron gas density and mobility along single NW-FETs. Notably, dc output and transfer characteristics of these n-type depletion mode NW-FETs reveal excellent drain current saturation and record low subthreshold slopes of 70 mV/dec at on/off ratios >10(4)-10(5) at room temperature.


Assuntos
Alumínio/química , Arsenicais/química , Gálio/química , Nanotecnologia , Nanofios/química , Elétrons , Semicondutores , Silício/química
14.
Int J Oral Maxillofac Surg ; 44(2): 203-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25277806

RESUMO

The aim of the present study was to compare subjective experiences using bur, ultrasonic, and sonic osteotomy systems. Ten novice (N) and 10 expert (E) practitioners performed osteotomies on bovine ribs with each system. They scored ease of handling and sense of accuracy on visual analogue scales. The duration of the osteotomy procedure and the amount of noise were recorded objectively. Learning experience was evaluated in a second run. The Mann-Whitney U-test, Wilcoxon signed rank tests, and Spearman's rank correlation coefficient were used for the statistical analyses. The sonic system was significantly slower, with the worst noise impact (92.9dB; standard deviation (SD) 7.1). However, both user groups improved significantly in the second run (N 7.9, E 7.6). There were no significant differences in handling. The sense of accuracy was evaluated to be significantly best for the sonic system (N 8.4, E 8.4), compared to the ultrasonic system (N 7.1, E 7.1; both P=0.043) and bur system (N 5.5, P=0.002; E 6.0, P=0.006). The practitioners had a promising experience with the application of the ultrasonic system and particularly with the sonic system.


Assuntos
Osteotomia/métodos , Procedimentos Cirúrgicos Ultrassônicos/métodos , Animais , Bovinos , Competência Clínica , Desenho de Equipamento , Técnicas In Vitro , Osteotomia/instrumentação , Piezocirurgia , Projetos Piloto , Costelas/cirurgia , Procedimentos Cirúrgicos Ultrassônicos/instrumentação
15.
Pflugers Arch ; 467(7): 1495-1508, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25163766

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has one of the worst survival rates of all cancers. ANO1 (TMEM16A) is a recently identified Ca(2+)-activated Cl(-) channel (CaCC) that is upregulated in several tumors. Although ANO1 was subject to extensive studies in the recent years, its pathophysiological function has only been poorly understood. The aim of the present study is to establish the significance of ANO1 in PDAC behavior and demarcate its roles in PDAC from those of the volume-regulated anion channel (VRAC). We performed qPCR and Western blot measurements on different PDAC cell lines (Panc-1, Mia PaCa 2, Capan-1, AsPC-1, BxPC-3) and compared the results to those obtained in a human pancreatic ductal epithelium (HPDE) cell line. All cancer cell lines showed an upregulation of ANO1 on mRNA and protein levels. Whole-cell patch-clamp recordings identified large Ca(2+) and voltage-dependent Cl(-) currents in PDAC cells. Using siRNA knockdown of ANO1 and three ANO1 inhibitors (T16Ainh-A01, CaCCinh-A01, and NS3728), we found that ANO1 is the main constituent of CaCC current in PDAC cells. We further characterized these three inhibitors and found that they had unspecific effects on the free intracellular calcium concentration. Functional studies on PDAC behavior showed that surprisingly inhibition of ANO1 did not influence cellular proliferation. On the other hand, we found ANO1 channel to be pivotal in PDAC cell migration as assessed in wound healing experiments.


Assuntos
Adenocarcinoma/metabolismo , Canais de Cloreto/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Anoctamina-1 , Cálcio/metabolismo , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/genética , Cloretos/metabolismo , Humanos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima
16.
Br J Pharmacol ; 171(12): 3077-88, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24611668

RESUMO

BACKGROUND AND PURPOSE: CYP2D6 metabolizes many centrally acting drugs, neurotoxins and endogenous neurochemicals, and differences in brain levels of CYP2D have been associated with brain function and drug response. Alcohol consumers and smokers have higher levels of CYP2D6 in brain, but not liver, suggesting ethanol and/or nicotine may induce human brain CYP2D6. We investigated the independent and combined effects of chronic ethanol self-administration and nicotine treatment on CYP2D expression in African green monkeys. EXPERIMENTAL APPROACH: Forty monkeys were randomized into control, ethanol-only, nicotine-only and ethanol + nicotine groups. Two groups voluntarily self-administered 10% ethanol in sucrose solution for 4 h·day(-1) , whereas two groups consumed sucrose solution on the same schedule. Two groups received daily s.c. injections of 0.5 mg·kg(-1) nicotine in saline bid, whereas two groups were injected with saline on the same schedule. KEY RESULTS: Both nicotine and ethanol dose-dependently increased CYP2D in brain; brain mRNA was unaffected, and neither drug altered hepatic CYP2D protein or mRNA. The combination of ethanol and nicotine increased brain CYP2D protein levels to a greater extent than either drug alone (1.2-2.2-fold, P < 0.05 among the eight brain regions assessed). Immunohistochemistry revealed the induction of brain CYP2D protein within specific cell types and regions in the treatment groups. CONCLUSIONS AND IMPLICATIONS: Ethanol and nicotine increase brain CYP2D protein levels in monkeys, in a region and treatment-specific manner, suggesting that CNS drug responses, neurodegeneration and personality may be affected among people who consume alcohol and/or nicotine.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Encéfalo/efeitos dos fármacos , Etanol/administração & dosagem , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Encéfalo/enzimologia , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Indução Enzimática , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , RNA Mensageiro/metabolismo , Autoadministração
17.
Orthop Traumatol Surg Res ; 100(1): 159-63, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24440546

RESUMO

BACKGROUND: Sacro-iliac arthrodesis usually requires an extended posterior approach, which is associated with a number of dreaded complications. Here, we assessed the feasibility of arthroscopic exploration of the dislocated sacro-iliac joint. MATERIALS AND METHODS: In the first step of our study, we used ligament section to induce loss of sacro-iliac joint coaptation in a cadaver. We then studied 5 patients with Tile C pelvic ring injuries. Arthroscopy was used to clear the joint of fibrous tissue and to roughen the bone to subchondral level in order to induce sacro-iliac arthrodesis. In addition, posterior fixation was performed using a hinge system or an ilio-sacral screw. RESULTS: The cadaver study confirmed the feasibility of sacro-iliac arthroscopy after disruption of the strong posterior inter-osseous ligament. In the clinical part of the study in 5 patients with Tile C pelvic ring injuries, arthroscopy allowed direct visualisation extending to the anterior part of the joint space. A power burr and synovial knife were introduced to remove the interposed fibrous tissue and to roughen the bone to subchondral level in order to induce joint fusion. In addition, percutaneous or open posterior fixation was performed in all 5 patients. No infectious complications were recorded. DISCUSSION: An arthroscope cannot be introduced into the normal sacro-iliac joint. In contrast, after traumatic sacro-iliac dislocation, arthroscopy can be used to evaluate the intra-articular injuries and to roughen the bone to subchondral level.


Assuntos
Artrodese/métodos , Artroscopia , Luxações Articulares/cirurgia , Articulação Sacroilíaca/lesões , Articulação Sacroilíaca/cirurgia , Adulto , Idoso , Cadáver , Estudos de Viabilidade , Feminino , Humanos , Masculino
18.
Pflugers Arch ; 466(10): 1899-910, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24419539

RESUMO

Anoctamin 6 (ANO6), also known as TMEM16F, has been shown to be a calcium-activated anion channel with delayed calcium activation. The cellular function of ANO6 is under debate, and different groups have come to different conclusions about ANO6's physiological role. Although it is now quite well established that ANO6 is distinct from the volume-regulated anion channel, it is still unclear whether ANO6 or other anoctamins can be activated by cell swelling. In this study, we suggest that ANO1, ANO6, and ANO10 do not contribute to the volume-activated current in ANO-overexpressing HEK293 cells. Furthermore, knock-down of ANO6 in Ehrlich ascites tumor cells (EATC) and Ehrlich-Lettre ascites (ELA) did not decrease but instead significantly increased swelling-activated membrane currents. Knock-down of ANO6 in EATC did not reduce regulatory volume decrease (RVD) in the absence of extracellular calcium, whereas it significantly reduced RVD in the presence of calcium. Interestingly, we found that knock-down of ANO6 in ELA cells resulted in a decrease in cisplatin-induced caspase-3 activity, confirming earlier findings that ANO6 is involved in apoptosis. Finally, knock-down of ANO1 and ANO6 did not affect the volume-sensitive release of taurine in ELA cells. Thus, our data provide evidence that ANO6 cannot be activated directly by cell swelling unless Ca(2+) is present. We also conclude that ANO6 carries a current during RVD, provided extracellular calcium is present. Thus, swelling activation of ANO6 requires the presence of free calcium.


Assuntos
Apoptose , Cálcio/metabolismo , Tamanho Celular , Proteínas de Transferência de Fosfolipídeos/metabolismo , Animais , Anoctamina-1 , Anoctaminas , Caspase 3/metabolismo , Linhagem Celular Tumoral , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Células HEK293 , Humanos , Camundongos , Proteínas de Transferência de Fosfolipídeos/genética , Taurina/metabolismo
19.
Pflugers Arch ; 465(12): 1753-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23832500

RESUMO

Members of the TMEM16 family have recently been described as Ca(2+)-activated Cl(-) channels. They have been implicated in cancer and appear to be associated with poor patient prognosis. Here, we investigate the role of TMEM16 channels in cell migration, which is largely unknown. We focused on TMEM16A and TMEM16F channels that have the highest expression of TMEM16 channels in Ehrlich Lettre ascites (ELA) cells. Due to the lack of specific pharmacological modulators, we employed a miRNA approach and stably knocked down the expression of TMEM16A and TMEM16F channels, respectively. Migration analysis shows that TMEM16A KD clones are affected in their directional migration, whereas TMEM16F KD clones show a 40 % reduced rate of cell migration. Moreover, TMEM16A KD clones have a smaller projected cell area, and they are rounder than TMEM16F KD clones. The morphological changes are linearly correlated with the directionality of cells. TMEM16A and TMEM16F, thus, have an important function in cell migration-TMEM16A in directional migration, TMEM16F in determination of the speed of migration. We conclude that TMEM16A and TMEM16F channels have a distinct impact on the steering and motor mechanisms of migrating ELA cells.


Assuntos
Movimento Celular/fisiologia , Canais de Cloreto/fisiologia , Proteínas de Transferência de Fosfolipídeos/fisiologia , Animais , Anoctamina-1 , Anoctaminas , Carcinoma de Ehrlich , Técnicas de Silenciamento de Genes , Camundongos
20.
Int J Oral Maxillofac Surg ; 42(12): 1510-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23769472

RESUMO

Retrobulbar haemorrhage is a sight-threatening condition that can occur after orbital trauma. The aim of this study was to evaluate the frequency and outcome of orbital haemorrhages following orbital fractures in geriatric patients receiving anticoagulants. All patients aged 65 years or more suffering from orbital fractures between 2008 and 2009 were included in this study. The mechanism of trauma, underlying diseases, and medication were recorded. In case of a retrobulbar haemorrhage, surgical exploration, the elapsed time between the onset of haemorrhage symptoms and surgical treatment, and the outcome regarding visual acuity were documented. Sixty-eight orbital fractures occurred (31 males, 37 females, age 65-95 years) resulting in six (3%) orbital haemorrhages. Four cases were associated with initial orbital bleeding, two other patients developed orbital haemorrhage as a complication after surgical reconstruction. Anticoagulant therapy, but not aspirin, was associated with a significantly increased risk of retrobulbar haematoma (p=0.02). Two patients permanently lost vision, two partial recoveries and two total recoveries were observed. Patients receiving anticoagulants have a higher risk of orbital haemorrhage after orbital fracture and should be monitored closely. Any evidence of visual impairment should lead to further investigation and prompt treatment.


Assuntos
Anticoagulantes/efeitos adversos , Hematoma/etiologia , Fraturas Orbitárias/complicações , Inibidores da Agregação Plaquetária/efeitos adversos , Hemorragia Retrobulbar/etiologia , Transtornos da Visão/etiologia , Acidentes por Quedas , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Fraturas Orbitárias/cirurgia , Tomografia Computadorizada por Raios X , Transtornos da Visão/diagnóstico
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