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2.
Strahlenther Onkol ; 200(7): 583-594, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38381142

RESUMO

BACKGROUND AND OBJECTIVE: Data on enteral tube feeding in head and neck cancer (HNC) patients undergoing chemoradiotherapy vary considerably between German institutions. This survey aims to investigate the management of feeding tubes in an interdisciplinary context across Germany. MATERIALS AND METHODS: Between December 2022 and May 2023, 70 participants (42 radiation oncologists, 12 medical oncologists, 14 head and neck surgeons, and 2 physicians covering several specialties) responded to our web-based survey. In addition to the type of institution (university hospital, private practice, etc.), their age, and professional experience (in years), participants were asked several questions on the indication and institutional policy for tube placement and management (prophylactic/reactive nasogastric or gastrostomy tube). All questions were mandatory single- or multiple-choice questions, while additional comments were possible by email. RESULTS: Most participants were employed at a university hospital (n = 52; 74.3%) and came from a radiation oncology background (n = 42; 60%). Fifty-four contributors (77.1%) reported that no nutritional risk screening prior to chemoradiotherapy was routinely performed, and 71.4% (n = 50) stated that no standardized protocol was used at the institution to set the indication for tube placement. Generally, policies and methods of tube feeding vary considerably between the individual institutions and specialties. However, the majority (n = 56, 80%) recommended a prophylactic percutaneous enteral gastrostomy (PEG) tube to their patients before chemoradiotherapy. Still, there was no consistent trend regarding the approach for reactive tube feeding. CONCLUSION: The policies and methods of tube feeding vary considerably between the individual institutions and specialties in Germany. In the era of individualized medicine, uniform protocols are difficult to establish. However, a baseline nutritional risk screening could simplify decision-making in clinical practice.


Assuntos
Quimiorradioterapia , Nutrição Enteral , Gastrostomia , Neoplasias de Cabeça e Pescoço , Intubação Gastrointestinal , Humanos , Alemanha , Neoplasias de Cabeça e Pescoço/terapia , Masculino , Inquéritos e Questionários , Padrões de Prática Médica/estatística & dados numéricos , Feminino , Pesquisas sobre Atenção à Saúde , Comunicação Interdisciplinar , Pessoa de Meia-Idade , Radio-Oncologistas
3.
Xenotransplantation ; 31(4): e12877, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39077824

RESUMO

INTRODUCTION: Inflammatory responses and coagulation disorders are a relevant challenge for successful cardiac xenotransplantation on its way to the clinic. To cope with this, an effective and clinically practicable anti-inflammatory and anti-coagulatory regimen is needed. The inflammatory and coagulatory response can be reduced by genetic engineering of the organ-source pigs. Furthermore, there are several therapeutic strategies to prevent or reduce inflammatory responses and coagulation disorders following xenotransplantation. However, it is still unclear, which combination of drugs should be used in the clinical setting. To elucidate this, we present data from pig-to-baboon orthotopic cardiac xenotransplantation experiments using a combination of several anti-inflammatory drugs. METHODS: Genetically modified piglets (GGTA1-KO, hCD46/hTBM transgenic) were used for orthotopic cardiac xenotransplantation into captive-bred baboons (n = 14). All animals received an anti-inflammatory drug therapy including a C1 esterase inhibitor, an IL-6 receptor antagonist, a TNF-α inhibitor, and an IL-1 receptor antagonist. As an additive medication, acetylsalicylic acid and unfractionated heparin were administered. The immunosuppressive regimen was based on CD40/CD40L co-stimulation blockade. During the experiments, leukocyte counts, levels of C-reactive protein (CRP) as well as systemic cytokine and chemokine levels and coagulation parameters were assessed at multiple timepoints. Four animals were excluded from further data analyses due to porcine cytomegalovirus/porcine roseolovirus (PCMV/PRV) infections (n = 2) or technical failures (n = 2). RESULTS: Leukocyte counts showed a relevant perioperative decrease, CRP levels an increase. In the postoperative period, leukocyte counts remained consistently within normal ranges, CRP levels showed three further peaks after about 35, 50, and 80 postoperative days. Analyses of cytokines and chemokines revealed different patterns. Some cytokines, like IL-8, increased about 2-fold in the perioperative period, but then decreased to levels comparable to the preoperative values or even lower. Other cytokines, such as IL-12/IL-23, decreased in the perioperative period and stayed at these levels. Besides perioperative decreases, there were no relevant alterations observed in coagulation parameters. In summary, all parameters showed an unremarkable course with regard to inflammatory responses and coagulation disorders following cardiac xenotransplantation and thus showed the effectiveness of our approach. CONCLUSION: Our preclinical experience with the anti-inflammatory drug therapy proved that controlling of inflammation and coagulation disorders in xenotransplantation is possible and well-practicable under the condition that transmission of pathogens, especially of PCMV/PRV to the recipient is prevented because PCMV/PRV also induces inflammation and coagulation disorders. Our anti-inflammatory regimen should also be applicable and effective in the clinical setting of cardiac xenotransplantation.


Assuntos
Animais Geneticamente Modificados , Transplante de Coração , Inflamação , Papio , Transplante Heterólogo , Animais , Transplante Heterólogo/métodos , Transplante de Coração/métodos , Suínos , Inflamação/imunologia , Coagulação Sanguínea/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Humanos , Xenoenxertos/imunologia , Galactosiltransferases/genética , Imunossupressores/farmacologia , Citocinas/metabolismo
4.
Nature ; 564(7736): 430-433, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30518863

RESUMO

Heart transplantation is the only cure for patients with terminal cardiac failure, but the supply of allogeneic donor organs falls far short of the clinical need1-3. Xenotransplantation of genetically modified pig hearts has been discussed as a potential alternative4. Genetically multi-modified pig hearts that lack galactose-α1,3-galactose epitopes (α1,3-galactosyltransferase knockout) and express a human membrane cofactor protein (CD46) and human thrombomodulin have survived for up to 945 days after heterotopic abdominal transplantation in baboons5. This model demonstrated long-term acceptance of discordant xenografts with safe immunosuppression but did not predict their life-supporting function. Despite 25 years of extensive research, the maximum survival of a baboon after heart replacement with a porcine xenograft was only 57 days and this was achieved, to our knowledge, only once6. Here we show that α1,3-galactosyltransferase-knockout pig hearts that express human CD46 and thrombomodulin require non-ischaemic preservation with continuous perfusion and control of post-transplantation growth to ensure long-term orthotopic function of the xenograft in baboons, the most stringent preclinical xenotransplantation model. Consistent life-supporting function of xenografted hearts for up to 195 days is a milestone on the way to clinical cardiac xenotransplantation7.


Assuntos
Transplante de Coração , Xenoenxertos/transplante , Papio , Suínos , Transplante Heterólogo , Animais , Anticorpos/análise , Anticorpos/sangue , Proteínas do Sistema Complemento/análise , Enzimas/sangue , Fibrina/análise , Galactosiltransferases/deficiência , Galactosiltransferases/genética , Xenoenxertos/patologia , Humanos , Fígado/enzimologia , Masculino , Proteína Cofatora de Membrana/genética , Proteína Cofatora de Membrana/metabolismo , Miocárdio/enzimologia , Necrose , Perfusão , Contagem de Plaquetas , Tempo de Protrombina , Trombomodulina/genética , Trombomodulina/metabolismo , Fatores de Tempo
5.
Strahlenther Onkol ; 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713170

RESUMO

PURPOSE: Patient misidentification in radiation oncology (RO) is a significant concern due to the potential harm to patient health and the burden on healthcare systems. Electronic patient identification systems (ePIS) are increasingly being used as an alternative or supplement to organizational systems (oPIS). The objective of this study was to assess the usability and usefulness of ePIS and oPIS in German-speaking countries. METHODS: A cross-sectional survey was designed by a group of experts from various professional backgrounds in RO. The survey consisted of 38 questions encompassing quantitative and qualitative data on usability, user experience, and usefulness of PIS. It was available between August and October 2022. RESULTS: Of 118 eligible participants, 37% had implemented some kind of ePIS. Overall, 22% of participants who use an oPIS vs. 10% of participants who use an ePIS reported adverse events in terms of patients' misidentification in the past 5 years. Frequent or very frequent drop-outs of electronic systems were reported by 31% of ePIS users. Users of ePIS significantly more often affirmed a positive cost-benefit ratio of ePIS as well as an improvement of workflow, whereas users of oPIS more frequently apprehended a decrease in staffs' attention through ePIS. The response rate was 8%. CONCLUSION: The implementation of ePIS can contribute to efficient PI and improved processes. Apprehensions by oPIS users and assessments of ePIS users differ significantly in aspects of the perceived usefulness of ePIS. However, technical problems need to be addressed to ensure the reliability of ePIS. Further research is needed to assess the impact of different PIS on patient safety in RO.

6.
Strahlenther Onkol ; 199(4): 350-359, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35931889

RESUMO

PURPOSE: Risk management (RM) is a key component of patient safety in radiation oncology (RO). We investigated current approaches on RM in German RO within the framework of the Patient Safety in German Radiation Oncology (PaSaGeRO) project. Aim was not only to evaluate a status quo of RM purposes but furthermore to discover challenges for sustainable RM that should be addressed in future research and recommendations. METHODS: An online survey was conducted from June to August 2021, consisting of 18 items on prospective and reactive RM, protagonists of RM, and self-assessment concerning RM. The survey was designed using LimeSurvey and invitations were sent by e­mail. Answers were requested once per institution. RESULTS: In all, 48 completed questionnaires from university hospitals, general and non-academic hospitals, and private practices were received and considered for evaluation. Prospective and reactive RM was commonly conducted within interprofessional teams; 88% of all institutions performed prospective risk analyses. Most institutions (71%) reported incidents or near-events using multiple reporting systems. Results were presented to the team in 71% for prospective analyses and 85% for analyses of incidents. Risk conferences take place in 46% of institutions. 42% nominated a manager/committee for RM. Knowledge concerning RM was mostly rated "satisfying" (44%). However, 65% of all institutions require more information about RM by professional societies. CONCLUSION: Our results revealed heterogeneous patterns of RM in RO departments, although most departments adhered to common recommendations. Identified mismatches between recommendations and implementation of RM provide baseline data for future research and support definition of teaching content.


Assuntos
Segurança do Paciente , Radioterapia (Especialidade) , Humanos , Radioterapia (Especialidade)/métodos , Estudos Prospectivos , Inquéritos e Questionários , Gestão de Riscos
7.
Strahlenther Onkol ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052968

RESUMO

PURPOSE: The aim of this work was to assess the current state of digitalization in radiation oncology departments in Germany, Austria, and Switzerland. METHODS: A comprehensive survey was conducted in a digital format, consisting of 53 questions that covered various aspects of digitalization including patient workflow, departmental organization, radiotherapy planning, and employee-related aspects. RESULTS: Overall, 120 forms were eligible for evaluation. Participants were mainly physicians or medical physicists responsible for digitalization aspects in their departments. Nearly 70% of the institutions used electronic patient records, with 50% being completely paperless. However, the use of smartphone apps for electronic patient reported outcomes (ePROMs) and digital health applications (DIGA) was limited (9% and 4.9%, respectively). In total, 70.8% of the radio-oncology departments had interfaces with diagnostic departments, and 36% had digital interchanges with other clinics. Communication with external partners was realized mainly through fax (72%), e­mails (55%), postal letters (63%), or other digital exchange formats (28%). Almost half of the institutions (49%) had dedicated IT staff for their operations. CONCLUSION: To the best of our knowledge, this survey is the first of its kind conducted in German-speaking radiation oncology departments within the medical field. The findings suggest that there is a varied level of digitalization implementation within these departments, with certain areas exhibiting lower rates of digitalization that could benefit from targeted improvement initiatives.

8.
Nutr Cancer ; 74(8): 2887-2895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35209777

RESUMO

Malnutrition negatively impacts quality of life (QoL) in patients with head and neck cancer (HNC). This is the first prospective study to assess the impact of malnutrition (defined by the bioelectrical impedance analysis (BIA)-derived fat-free mass index) on QoL in patients with HNC undergoing (chemo)radiotherapy. Between October 2018 and October 2020, 58 HNC patients prospectively completed the QoL-questionnaires EORTC-QLQ-C30 and EORTC-QLQ-H&N35 at the beginning (tb) and at the end of (chemo)radiotherapy (te) as well as during follow-up (tf). At these time points, nutritional risk assessment (MUST, NRS-2002, Nutriscore), BIA measurement and laboratory testing was performed by a permanent study team. Differences between malnourished (n = 14) and well-nourished patients (n = 44) were observed in UICC classification (P < 0.001) and HPV status (P = 0.03). Well-nourished patients showed higher baseline hemoglobin (P = 0.025) and albumin (P = 0.005), but lower c-reactive protein levels (P < 0.001). At tb, mostly malnourished patients presented with worse QoL. Multivariable analysis showed that MUST, NRS-2002, HPV status, and UICC classification were related to QoL. Nutritional status has a crucial impact on QoL. The nutritional screening protocols MUST and NRS-2002 are suitable for identifying patients at risk and predicting QoL in patients with HNC undergoing (chemo)radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Desnutrição , Infecções por Papillomavirus , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Desnutrição/etiologia , Avaliação Nutricional , Estado Nutricional , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários
9.
Circulation ; 142(9): 868-881, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32508131

RESUMO

BACKGROUND: Ischemic heart diseases are leading causes of death and reduced life quality worldwide. Although revascularization strategies significantly reduce mortality after acute myocardial infarction (MI), a large number of patients with MI develop chronic heart failure over time. We previously reported that a fragment of the extracellular matrix protein agrin promotes cardiac regeneration after MI in adult mice. METHODS: To test the therapeutic potential of agrin in a preclinical porcine model, we performed ischemia-reperfusion injuries using balloon occlusion for 60 minutes followed by a 3-, 7-, or 28-day reperfusion period. RESULTS: We demonstrated that local (antegrade) delivery of recombinant human agrin to the infarcted pig heart can target the affected regions in an efficient and clinically relevant manner. A single dose of recombinant human agrin improved heart function, infarct size, fibrosis, and adverse remodeling parameters 28 days after MI. Short-term MI experiments along with complementary murine studies revealed myocardial protection, improved angiogenesis, inflammatory suppression, and cell cycle reentry as agrin's mechanisms of action. CONCLUSIONS: A single dose of agrin is capable of reducing ischemia-reperfusion injury and improving heart function, demonstrating that agrin could serve as a therapy for patients with acute MI and potentially heart failure.


Assuntos
Agrina/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Recuperação de Função Fisiológica/efeitos dos fármacos , Animais , Humanos , Camundongos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Proteínas Recombinantes/farmacologia , Suínos
10.
Strahlenther Onkol ; 196(12): 1128-1134, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32951162

RESUMO

PURPOSE: Patients and staffs are endangered by different failure modes during clinical routine in radiation oncology and risks are difficult to stratify. We implemented the method of failure mode and effects analysis (FMEA) via questionnaires in our institution and introduced an adapted scale applicable for radiation oncology. METHODS: Failure modes in physical treatment planning and daily routine were detected and stratified by ranking occurrence, severity, and detectability in a questionnaire. Multiplication of these values offers the risk priority number (RPN). We implemented an ordinal rating scale (ORS) as a combination of earlier published scales from the literature. This scale was optimized for German radiation oncology. We compared RPN using this ORS versus use of a rather subjective visual analogue rating scale (VRS). RESULTS: Mean RPN using ORS was 62.3 vs. 67.5 using VRS (p = 0.7). Use of ORS led to improved completeness of questionnaires (91 vs. 79%) and stronger agreement among the experts, especially concerning failure modes during radiation routine. The majority of interviewed experts found the analysis by using the ORS easier and expected a saving of time as well as higher intra- and interobserver reliability. CONCLUSION: The introduced rating scale together with a questionnaire survey provides merit for conducting FMEA in radiation oncology as results are comparable to the use of VRS and the process is facilitated.


Assuntos
Análise do Modo e do Efeito de Falhas na Assistência à Saúde/métodos , Neoplasias/radioterapia , Alemanha , Humanos , Radioterapia (Especialidade)/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Inquéritos e Questionários , Fluxo de Trabalho
11.
Reprod Fertil Dev ; 31(4): 820-826, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30384878

RESUMO

Immunosurgical isolation of the inner cell mass (ICM) from blastocysts is based on complement-mediated lysis of antibody-coated trophectoderm (TE) cells. Conventionally, anti-species antisera, containing antibodies against multiple undefined TE-cell epitopes, have been used as the antibody source. We previously generated α-1,3-galactosyltransferase deficient (GTKO) pigs to prevent hyperacute rejection of pig-to-primate xenotransplants. Since GTKO pigs lack galactosyl-α-1,3-galactose (αGal) but are exposed to this antigen (e.g. αGal on gut bacteria), they produce anti-αGal antibodies. In this study, we examined whether serum from GTKO pigs could be used as a novel antibody source for multi-species embryo immunosurgery. Mouse, rabbit, pig and cattle blastocysts were used for the experiment. Expression of αGal epitopes on the surface of TE cells was detected in blastocysts of all species tested. GTKO pig serum contained sufficient anti-αGal antibodies to induce complement-mediated lysis of TE cells in blastocysts from all species investigated. Intact ICMs could be successfully recovered and the majority showed the desired level of purity. Our study demonstrates that GTKO pig serum is a reliable and effective source of antibodies targeting the αGal epitopes of TE cells for multi-species embryo immunosurgery.


Assuntos
Blastocisto/imunologia , Epitopos , Galactose/imunologia , Animais , Bovinos , Camundongos , Coelhos , Suínos
12.
Int J Mol Sci ; 20(19)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557793

RESUMO

Coronary heart diseases are of high relevance for health care systems in developed countries regarding patient numbers and costs. Disappointingly, the enormous effort put into the development of innovative therapies and the high numbers of clinical studies conducted are counteracted by the low numbers of therapies that become clinically effective. Evidently, pre-clinical research in its present form does not appear informative of the performance of treatments in the clinic and, even more relevant, it appears that there is hardly any consent about how to improve the predictive capacity of pre-clinical experiments. According to the steadily increasing relevance that pig models have gained in biomedical research in the recent past, we anticipate that research in pigs can be highly predictive for ischemia-reperfusion injury (IRI) therapies as well. Thus, we here describe the significance of pig models in IRI, give an overview about recent developments in evaluating such models by clinically relevant methods and present the latest insight into therapies applied to pigs under IRI.


Assuntos
Biomarcadores , Suscetibilidade a Doenças , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Animais , Biomimética , Modelos Animais de Doenças , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Óxido Nítrico/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Suínos
13.
Xenotransplantation ; 25(5): e12390, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29536572

RESUMO

BACKGROUND: In pig-to-human xenotransplantation, early cellular rejection reactions are mediated by natural killer cells (NK cells). Human NK cells are inhibited by HLA-E via CD94/NKG2A receptors. To protect porcine grafts against human NK cell responses, transgenic GTKO pigs expressing hCD46 and HLA-E have been generated. The aim of this study was to test the effect of this genetic modification on xenogeneic, and in particular human NK cell response, using an ex vivo perfusion model of pig hearts with human blood. METHODS: Cardiopleged and explanted genetically modified (gm) pig hearts (GTKO/hCD46/HLA-E/hß2-microglobulin) and wild-type (wt) controls (n = 6 each) were reperfused and tested in an 8 hours ex vivo perfusion system using freshly drawn human blood. Cardiac function was evaluated during a 165-minute period in working heart mode. Myocardial damage, antibody deposition, complement activation, and coagulation parameters were evaluated histologically at the end of perfusion. The number of NK cells in the perfusate was determined by flow cytometry at baseline and at 8 hours; tissue infiltration by NK cells was quantified by immunofluorescence microscopy using NKp46 staining of frozen sections. RESULTS: Deposition of IgG (1.2 ± 1 × 107 vs 8.8 ± 2.9 × 106 ; P < .01), IgM (4.4 ± 3.7 × 106 vs 1.7 ± 1.2 × 106 ; P < .01), and the complement activation product C4b/c (3.5 ± 1.3 × 106 vs 2.3 × 106  ± 9.4 × 105 ; P > .01) was lower in gm than wt hearts. NK cell percentages of leukocytes in the perfusate decreased from 0.94 ± 0.77% to 0.21 ± 0.25% (P = .04) during xenoperfusion of wt hearts. In contrast, the ratio of NK cells did not decrease significantly in the gm hearts. In this group, NK cell myocardial infiltration after 480 minutes of perfusion was lower than in wt organs (2.5 ± 3.7 × 104 /mm3 vs 1.3 ± 1.4 × 105 /mm3 ; P = .0001). The function of gm hearts was better preserved compared to wt organs, as demonstrated by higher cardiac index during the first 2 hours of ex vivo perfusion. CONCLUSION: GTKO, hCD46, and HLA-E expression in porcine hearts reduced complement deposition, complement dependent injury, and myocardial NK cell infiltration during perfusion with human blood. This tested combination of genetic modifications may minimize damage from acute human-anti-pig rejection reactions and improve myocardial function after xenotransplantation.


Assuntos
Animais Geneticamente Modificados/imunologia , Ativação do Complemento/imunologia , Coração , Xenoenxertos/imunologia , Células Matadoras Naturais/imunologia , Animais , Células Endoteliais/imunologia , Humanos , Leucócitos/metabolismo , Miocárdio/imunologia , Suínos , Transplante Heterólogo/métodos
14.
Xenotransplantation ; 22(6): 443-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26490671

RESUMO

BACKGROUND: Intraportal infusion is currently the method of choice for clinical islet cell transplantation but suffers from poor efficacy. As the liver may not represent an optimal transplantation site for Langerhans islets, we examined the potential of neonatal porcine islet-like clusters (NPICCs) to engraft in skeletal muscle as an alternative transplantation site. METHODS: Neonatal porcine islet-like clusters were isolated from 2- to 5-day-old piglets and either transplanted under the kidney capsule (s.k.) or injected into the lower hindlimb muscle (i.m.) of streptozotocin-diabetic NOD-SCID IL2rγ(-/-) (NSG) mice. Survival, vascularization, maturation, and functional activity were analyzed by intraperitoneal glucose tolerance testing and immunohistochemical analyses. RESULTS: Intramuscular transplantation of NPICCs resulted in development of normoglycemia and restored glucose homeostasis. Time to reversal of diabetes and glucose tolerance (AUC glucose and AUC insulin) did not significantly differ as compared to s.k. transplantation. Intramuscular grafts exhibited rapid neovascularization and graft composition with cytokeratin-positive ductal cells and beta cells at post-transplant weeks 2 and 8 and after establishment of normoglycemia was comparable in both groups. CONCLUSIONS: Intramuscular injection represents a minimally invasive but efficient alternative for transplantation of NPICCs and, thus, offers an attractive alternative site for xenotransplantation approaches. These findings may have important implications for improving the outcome and the monitoring of pig islet xenotransplantation.


Assuntos
Diabetes Mellitus Experimental/patologia , Sobrevivência de Enxerto/fisiologia , Insulina/sangue , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Animais , Glicemia/análise , Teste de Tolerância a Glucose/métodos , Transplante das Ilhotas Pancreáticas/métodos , Camundongos Endogâmicos NOD , Camundongos SCID , Suínos , Fatores de Tempo
15.
Xenotransplantation ; 22(6): 427-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26602740

RESUMO

BACKGROUND: As a step towards clinical cardiac xenotransplantation, our experimental heterotopic intrathoracic xenotransplantation model offers a beating and ejecting donor heart while retaining the recipient's native organ as a backup in case of graft failure. Clinically applicable immunosuppressive regimens (IS) were investigated first, then treatments known to be effective in hypersensitized patients or those with recalcitrant rejection reactions. METHODS: Consecutive experiments were carried out between 2009 and 2013. Twenty-one genetically modified pigs (GGTA1-knockout/hCD46/± thrombomodulin, in one case HLA-E instead) were used as donors. In all experiments, two cycles of immunoabsorption reduced preformed antibodies. Recipient baboons were divided into two groups according to IS regimen: In group one (n = 10), pre-treatment started either one (anti-CD20) or four weeks (anti-CD20 plus the proteasome inhibitor bortezomib) prior to transplantation. The extended conventional (as for allotransplantation) immunosuppressive maintenance regimen included anti-thymocyte globuline, tacrolimus, mycophenolate mofetil, methylprednisolone and weekly anti-CD20. In group two (n = 11), myeloablative pre-treatment as in multiple myeloma patients (long and short regimens) was added to extended conventional IS; postoperative total thoracic and abdominal lymphoid irradiation (TLI; single dose of 600 cGY) was used to further reduce antibody-producing cells. RESULTS: In the perioperative course, the surgical technique was safely applied: 19 baboons were weaned off extracorporeal circulation and 17 extubated. Nine animals were lost in the early postoperative course due to causes unrelated to surgical technique or IS regimen. Excluding these early failures, median graft survival times of group 1 and 2 were 18.5 (12-50) days and 16 (7-35) days. Necropsy examination of group 1 donor organs revealed hypertrophy of the left ventricular wall in the six longer-lasting grafts; myocardial histology confirmed pre-clinical suspicion of humoral rejection, which was not inhibited by the extended conventional IS including intensified treatments, and signs of thrombotic microangiopathy. Grafts of group 2 presented with only mild-to-moderate features of humoral rejection and thrombotic microangiopathy, except in one case of delayed rejection on day 17. The other experiments in this group were terminated because of untreatable pulmonary oedema, recurring ventricular fibrillation, Aspergillus sepsis, as well as a combination of a large donor organ and late toxic side effects due to TLI. CONCLUSIONS: Longer-term results were difficult to achieve in this model due to the IS regimens used. However, we conclude that heterotopic intrathoracic heart transplantation may be an option for clinical xenotransplantation.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração , Imunossupressores/farmacologia , Animais , Animais Geneticamente Modificados , Anticorpos/imunologia , Anticorpos/farmacologia , Transplante de Coração/métodos , Suínos , Transplante Heterólogo/métodos
16.
BMJ Open ; 14(8): e086214, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153790

RESUMO

INTRODUCTION: Ensuring patient safety in radiation oncology is crucial for delivering high-quality healthcare. Patient safety indicators (PSIs) provide a mechanism for identifying, quantifying and evaluating risks and the effectiveness of safety measures. However, there is currently no specialised set of PSIs tailored for radiation oncology in Germany. This study seeks to: (1) create PSIs specifically designed for radiation oncology settings, (2) develop and psychometrically validate an instrument for assessing safety in German radiation oncology facilities and (3) evaluate the feasibility of implementing this instrument in routine clinical practice. The finalised questionnaire will serve as a self-assessment instrument for radiation oncology departments, aiding them in evaluating their efficacy in ensuring patient safety, prioritising safety interventions and tracking performance over time. METHODS AND ANALYSIS: We are undertaking a 3-year, mixed methods study to address our objectives. For the identification of PSIs, we will conduct a comprehensive review on the PubMed database, along with reviewing national and international guidelines and recommendations. To refine the initial set of indicators, we will consult with experts, including physicians, medical physicists, nurses, administrators and radiation therapists through focus groups. We will employ a Delphi study for the final consensus and selection of indicators. Additionally, the perspectives of patients will be incorporated by formation of a project patient's committee which meets throughout the project phases. We will reformulate the identified PSIs into questionnaire items. The questionnaire's clarity and comprehensibility will be validated through cognitive interviews, followed by psychometric testing in a pilot group of over 150 participants from German radiation oncology departments. The final version of the questionnaire will then be implemented in routine healthcare settings and we will interview individual users about their experiences with the questionnaire in semistructured interviews. We will convene a subsequent expert workshop to discuss the study results and explore avenues for the questionnaire's broader implementation. The finalised questionnaire will be made accessible via a web app. We hereby present the study potocol as a pre-results report. ETHICS AND DISSEMINATION: Ethical approval for this study was granted by the Hamburg Ethics Committee (Approval Number: 2023-101018-BO-ff). This trial is registered by the ARO (Arbeitsgemeinschaft Radioonkologie /working group for radiation oncology of the German Cancer Society), protocol number 2023-03 and in the German register for clinical trials with the number DRKS00034690. Study results will be published in conference papers and talks as well as journal papers with focus on open access journals. The results will be also disseminated during the implementation workshop in phase III, which will involve a diverse group of stakeholders. TRIAL REGISTRATION NUMBER: DRKS00034690.


Assuntos
Segurança do Paciente , Psicometria , Radioterapia (Especialidade) , Humanos , Alemanha , Radioterapia (Especialidade)/normas , Inquéritos e Questionários , Técnica Delphi , Projetos de Pesquisa , Reprodutibilidade dos Testes
17.
BMC Biotechnol ; 13: 43, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23688045

RESUMO

BACKGROUND: Somatic cell nuclear transfer (SCNT) using genetically engineered donor cells is currently the most widely used strategy to generate tailored pig models for biomedical research. Although this approach facilitates a similar spectrum of genetic modifications as in rodent models, the outcome in terms of live cloned piglets is quite variable. In this study, we aimed at a comprehensive analysis of environmental and experimental factors that are substantially influencing the efficiency of generating genetically engineered pigs. Based on a considerably large data set from 274 SCNT experiments (in total 18,649 reconstructed embryos transferred into 193 recipients), performed over a period of three years, we assessed the relative contribution of season, type of genetic modification, donor cell source, number of cloning rounds, and pre-selection of cloned embryos for early development to the cloning efficiency. RESULTS: 109 (56%) recipients became pregnant and 85 (78%) of them gave birth to offspring. Out of 318 cloned piglets, 243 (76%) were alive, but only 97 (40%) were clinically healthy and showed normal development. The proportion of stillborn piglets was 24% (75/318), and another 31% (100/318) of the cloned piglets died soon after birth. The overall cloning efficiency, defined as the number of offspring born per SCNT embryos transferred, including only recipients that delivered, was 3.95%. SCNT experiments performed during winter using fetal fibroblasts or kidney cells after additive gene transfer resulted in the highest number of live and healthy offspring, while two or more rounds of cloning and nuclear transfer experiments performed during summer decreased the number of healthy offspring. CONCLUSION: Although the effects of individual factors may be different between various laboratories, our results and analysis strategy will help to identify and optimize the factors, which are most critical to cloning success in programs aiming at the generation of genetically engineered pig models.


Assuntos
Animais Geneticamente Modificados/fisiologia , Técnicas de Transferência Nuclear/estatística & dados numéricos , Suínos/fisiologia , Animais , Animais Geneticamente Modificados/genética , Blastocisto/fisiologia , Clonagem Molecular , Interpretação Estatística de Dados , Feminino , Técnicas de Inativação de Genes , Masculino , Gravidez , Estações do Ano , Natimorto , Suínos/genética
18.
Cancers (Basel) ; 15(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38136257

RESUMO

This biophysical study aimed to determine fitting parameters for the Lyman-Kutcher-Burman (LKB) dose-response model for normal tissue complication probability (NTCP) calculations of acute side effects and to investigate the impact of reduced radiation doses on the probability of their occurrence in supradiaphragmatic non-Hodgkin lymphoma (NHL) irradiation. A cohort of 114 patients with NHL in the cervicothoracic region, treated between 2015 and 2021 at the University Hospitals of Münster, Hamburg, and Essen, with involved site radiation therapy (ISRT), were included. Among them, 68 patients with aggressive NHL (a-NHL) received consolidative radiation therapy with 24-54 Gy following (R-)CHOP chemotherapy. Additionally, 46 patients with indolent NHL (i-NHL) underwent radiotherapy with 22.5-45.0 Gy. Two treatment plans were prospectively created for each patient (a-NHL: 30.0/40.0 Gy; i-NHL: 24.0/30.0 Gy). NTCP were then calculated using the optimized LKB model. The adapted dose-response models properly predicted the patient's probability of developing acute side effects when receiving doses ≤ 50 Gy. In addition, it was shown that reduced radiation doses can influence the NTCP of acute side effects depending on the aggressiveness of NHL significantly. This study provided a foundation to prospectively assess the probability of adverse side effects among today's reduced radiation doses in the treatment of NHL.

19.
Radiat Oncol ; 17(1): 194, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443849

RESUMO

BACKGROUND AND PURPOSE: Malignant melanoma constitutes an aggressive tumor of the skin, the pathogenesis of which is influenced by immunological processes. In this context, the influence of radiotherapy (RT) on inflammatory markers has not been studied in detail, yet. MATERIALS AND METHODS: In this prospective analysis, 28 patients were recruited, 24 of these could be included for further analysis. According to protocol, patients underwent three blood-draws: before, after half of RT-fractions and after completion of RT. Serum levels of programmed death-ligand (PD-L) 1 and 2, interleukin 6 and cytotoxic t-lymphocyte-associated protein 4 were assessed via enzyme-linked immunosorbent assay and compared to healthy volunteers. Correlation with clinical data was attempted. RESULTS: Comparing patients with healthy volunteers, a significant difference in the mean baseline serum-level of PD-L1 (90.1 pg/ml vs. 76.7 pg/ml for patients vs. control, respectively; p = 0.024) and PD-L2 (4.4 ng/ml vs. 8.7 ng/ml; p = 0.04) could be found. Increased levels of PD-L1 were only found in patients with prior immunotherapy. There was a tendency for higher interleukin 6 levels in the patients (8.5 pg/ml vs. 0.6 pg/ml; p = 0.052). No significant differences in serum levels could be found between the three time points. CONCLUSION: The present study reveals a characteristic immunological pattern for melanoma patients in comparison to healthy controls. Future studies will have to focus on a putative correlation between immunological markers and clinical outcome parameters.


Assuntos
Melanoma , Radioterapia (Especialidade) , Neoplasias Cutâneas , Humanos , Antígeno B7-H1 , Interleucina-6 , Melanoma/radioterapia , Neoplasias Cutâneas/radioterapia , Microambiente Tumoral
20.
Neurooncol Pract ; 9(1): 59-67, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35096404

RESUMO

BACKGROUND: There is a pressing demand for more accurate, disease-specific quality measures in the field of neurosurgery. Aiming at most adequately measuring and reflecting the quality of glioma therapy, we developed a novel quality indicator bundle in form of a checklist for all patients that are treated operatively for glioma. METHODS: On the basis of possible glioma-specific quality indicators retrieved from the literature and quality guidelines, a multidisciplinary team developed a checklist containing 13 patient-need-specific outcome measures. Subsequently, the checklist was prospectively applied to a total of 78 patients compared with a control group consisting of 322 patients. A score was generated based on the maximum of quality measures achieved. RESULTS: Significant improvements in quality after prospectively introducing the checklist were achieved for supplemental physical and occupational therapy during inpatient stay (89.4% vs 100%, P = .002), consultation of a social worker during inpatient stay (64% vs 92.3%, P < .001), psycho-oncological screening (14.3% vs 70.5%, P < .001), psycho-oncological consultation (31.1% vs 82.1%, P < .001), and consultation of the palliative care team (20% vs 40%, P = .031). Overall, after introduction of the checklist one-third (n = 23) of patients reached best-practice measures in all categories, and over half of the patients (n = 44) achieved above 90% with respect to the outcome measures. CONCLUSIONS: Aiming at ensuring comprehensive, consistent, and timely care of glioma patients, the implementation of the checklist for routine use in glioma surgery represents an efficient, easily reproducible, and powerful tool for significant improvements.

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