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1.
Blood ; 140(20): 2113-2126, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-35704690

RESUMO

The BCL2 inhibitor venetoclax has been approved to treat different hematological malignancies. Because there is no common genetic alteration causing resistance to venetoclax in chronic lymphocytic leukemia (CLL) and B-cell lymphoma, we asked if epigenetic events might be involved in venetoclax resistance. Therefore, we employed whole-exome sequencing, methylated DNA immunoprecipitation sequencing, and genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 screening to investigate venetoclax resistance in aggressive lymphoma and high-risk CLL patients. We identified a regulatory CpG island within the PUMA promoter that is methylated upon venetoclax treatment, mediating PUMA downregulation on transcript and protein level. PUMA expression and sensitivity toward venetoclax can be restored by inhibition of methyltransferases. We can demonstrate that loss of PUMA results in metabolic reprogramming with higher oxidative phosphorylation and adenosine triphosphate production, resembling the metabolic phenotype that is seen upon venetoclax resistance. Although PUMA loss is specific for acquired venetoclax resistance but not for acquired MCL1 resistance and is not seen in CLL patients after chemotherapy-resistance, BAX is essential for sensitivity toward both venetoclax and MCL1 inhibition. As we found loss of BAX in Richter's syndrome patients after venetoclax failure, we defined BAX-mediated apoptosis to be critical for drug resistance but not for disease progression of CLL into aggressive diffuse large B-cell lymphoma in vivo. A compound screen revealed TRAIL-mediated apoptosis as a target to overcome BAX deficiency. Furthermore, antibody or CAR T cells eliminated venetoclax resistant lymphoma cells, paving a clinically applicable way to overcome venetoclax resistance.


Assuntos
Neoplasias Hematológicas , Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Reguladoras de Apoptose/genética , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Linfoma Difuso de Grandes Células B/patologia , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Epigênese Genética
2.
Anaesthesia ; 74(7): 896-903, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31062348

RESUMO

Central venous catheter insertion is a routine procedure performed by anaesthetists in the peri-operative setting. Upper body central venous catheters are usually placed such that their tip lies within the superior vena cava or at the cavo-atrial junction. Positioning the tip 'too low' in the right atrium has long been argued against on the basis that it increases the risk of perforation, leading to cardiac tamponade. Positioning the tip 'too high' in the brachiocephalic vein or above can also be problematic in that proximal migration can result in extravascular placement of the proximal lumen. Such an incident occurred at our hospital in 2016, resulting in extravasation of a vesicant medication causing tissue necrosis. We undertook a quality improvement project involving a standardised bundle of care and a peri-operative central venous catheter insertion checklist with the aim of reducing the risk of such an incident re-occurring. We conducted a three-month pre-intervention audit (n = 84) in 2016 and a post-intervention audit (n = 84) in 2017. Compared with the pre-intervention audit, the post-intervention audit coincided with a lower rate of central venous catheter tip malpositioning (5.6% vs. 9.2%); and a higher rate of 'optimal' central venous catheter tip position in the distal superior vena cava or cavo-atrial junction (45.1% vs. 29.2%). The central venous catheter insertion checklist also substantially improved documentation of sterility measures, insertion depth and post-insertional documentation of tip position on chest radiograph.


Assuntos
Cateterismo Venoso Central/instrumentação , Cateterismo Venoso Central/métodos , Cateteres Venosos Centrais , Lista de Checagem/métodos , Melhoria de Qualidade , Austrália , Humanos , Guias de Prática Clínica como Assunto , Estudos Retrospectivos
4.
Z Geburtshilfe Neonatol ; 219(6): 281-8, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26098383

RESUMO

BACKGROUND: Vaginal birth after Caesarean (VBAC) in out-of-hospital settings is controversial. With increasing Caesarean rates, more women with a prior Caesarean will decide to give birth in midwife-led birth-centres or at home. Therefore the study explores the question about maternal and neonatal outcomes in German out-of-hospital settings. METHOD: A retrospective study of German out-of-hospital data from 2005 to 2011 was undertaken. Included were 66,437 singleton pregnancies in cephalic presentation at term. This study describes the outcome parameters of first paras compared to mothers with their second child who had a prior Caesarean. RESULTS: The VBAC rate was 77.8%, and the first para vaginal birth rate was 89.8% (p<0.001). The intrapartum transfer rate of women with a prior Caesarean section was significantly more than for the first paras (38.2 vs. 27.2%; p<0.001). A prolonged first stage was the most frequently documented indication for intrapartal transfer in both groups. There were no significant differences in rates of maternal postpartum complications, or in postpartum hospital transfer rates. Also, neither neonatal transfer rates nor Apgar scores were statistically different between the groups. DISCUSSION: These results are consistent with other studies which reported that an out-of-hospital setting is an alternative to the clinical setting for women with a prior Caesarean. However, the fact that the intrapartum transfer rate of women with a prior Caesarean was almost 40% should be included in antenatal counselling about the place of labour and birth.


Assuntos
Cesárea/estatística & dados numéricos , Parto Normal/estatística & dados numéricos , Complicações do Trabalho de Parto/epidemiologia , Transferência de Pacientes/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Adulto , Feminino , Alemanha/epidemiologia , Parto Domiciliar/estatística & dados numéricos , Humanos , Gravidez/estatística & dados numéricos , Prevalência , Fatores de Risco
5.
Z Geburtshilfe Neonatol ; 218(5): 195-202, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25353213

RESUMO

BACKGROUND: Even though vaginal birth after Caesarean section (VBAC) is recommended, an out-of-hospital setting is discussed controversially. First of all, uterine rupture and placental complications are named. Nevertheless, an increasing number of women with a prior Caesarean section decide to give birth in an out-of-hospital setting. What is the maternal and neonatal outcome in international studies in these cases? METHOD: The databases of Medline, Cinahl, Embase and Cochrane Library on vaginal birth after Caesarean section in out-of-hospital settings were searched. Included are studies in German and English language without a limit on year of publication, which describe maternal and neonatal outcomes. RESULTS: 5 studies were found. All of them describe a high VBAC rate (73.5-98%). Only one study found uterine ruptures. Haemorrhage/placental complications were described in 2 studies (0.5 and 1.7%). None of the studies found maternal deaths. Neonatal death was described in 3 studies in a range from 0 -1.7%. DISCUSSION: There is a wide difference in the population of the studies. An important difference is the parity of the women and the prior mode of birth. 4 of the 5 studies do not see a reason not to try VBAC in an out-of-hospital setting. Further studies are necessary to inform the increasing number of women who decide to try VBAC in an out-of-hospital setting.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Morte Materna/estatística & dados numéricos , Morte Perinatal/prevenção & controle , Resultado da Gravidez/epidemiologia , Ruptura Uterina/mortalidade , Nascimento Vaginal Após Cesárea/mortalidade , Feminino , Humanos , Recém-Nascido , Internacionalidade , Gravidez , Prevalência , Fatores de Risco , Taxa de Sobrevida
6.
Int J Oral Maxillofac Surg ; 52(2): 168-174, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35659500

RESUMO

Free flaps are commonly used for head and neck reconstruction. However, flap dimensions are still evaluated by visual and tactile assessment. The aim of this study was to enable preoperative planning of flap dimensions for soft tissue reconstruction based on clinical parameters. Computed tomography records from 230 patients dated from 2009 to 2019 were analysed retrospectively. A virtual, three-dimensional anterolateral thigh flap model was standardized, aligned to segmented leg models in two positions, and flap thicknesses and volumes were determined. Associations of flap thickness and volume with clinical parameters were evaluated, and an approximative calculation method was derived. The laterally positioned anterolateral thigh flap showed an average (interquartile range) thickness of 15.6 mm (8.7 mm) and volume of 1.5 cm3 (0.9 cm3) per cm2. The medially positioned anterolateral thigh flap showed an average (interquartile range) thickness of 16.3 mm (8.7 mm) and volume of 1.6 cm3 (0.9 cm3) per cm2. For both flap positions, leg circumference was the strongest predictor of flap thickness (ß = 0.545, P < 0.001 and ß = 0.529, P < 0.001) and flap volume (ß = 0.523, P < 0.001 and ß = 0.480, P < 0.001). Flap dimensions can be calculated based on leg circumference, and this preoperative planning of flap dimensions can help the surgeon to select the appropriate flap.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Humanos , Coxa da Perna/cirurgia , Estudos Retrospectivos , Cabeça/cirurgia , Transplante de Pele
8.
R Soc Open Sci ; 5(10): 181227, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30473858

RESUMO

Evaluating how populations are connected by migration is important for understanding species resilience because gene flow can facilitate recovery from demographic declines. We therefore investigated the extent to which migration may have contributed to the global recovery of the Antarctic fur seal (Arctocephalus gazella), a circumpolar distributed marine mammal that was brought to the brink of extinction by the sealing industry in the eighteenth and nineteenth centuries. It is widely believed that animals emigrating from South Georgia, where a relict population escaped sealing, contributed to the re-establishment of formerly occupied breeding colonies across the geographical range of the species. To investigate this, we interrogated a genetic polymorphism (S291F) in the melanocortin 1 receptor gene, which is responsible for a cream-coloured phenotype that is relatively abundant at South Georgia and which appears to have recently spread to localities as far afield as Marion Island in the sub-Antarctic Indian Ocean. By sequencing a short region of this gene in 1492 pups from eight breeding colonies, we showed that S291F frequency rapidly declines with increasing geographical distance from South Georgia, consistent with locally restricted gene flow from South Georgia mainly to the South Shetland Islands and Bouvetøya. The S291F allele was not detected farther afield, suggesting that although emigrants from South Georgia may have been locally important, they are unlikely to have played a major role in the recovery of geographically more distant populations.

9.
Biochim Biophys Acta ; 428(3): 720-5, 1976 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-6056

RESUMO

The apparent pK for benzimidazole displacement of a number of cobalamins is markedly affected by the presence of sodium lauryl sulfate micelles. However, micelles of cetyltrimethylammonium bromide or Triton X have little or no effect on the pK. By measuring the apparent pK as a function of sodium lauryl sulfate concentration, the association constants between the micelles and both base on and base off methylcobalamin were calculated. This calculation indicates that the base off form is strongly associated with the micelle while the base on form is not.


Assuntos
Coloides , Micelas , Vitamina B 12 , Sítios de Ligação , Concentração de Íons de Hidrogênio , Cinética , Matemática , Vitamina B 12/análogos & derivados , Água
11.
Theriogenology ; 39(3): 611-22, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16727240

RESUMO

One- and 2-cell porcine embryos were obtained from oviductal flushes and cultured for 96 hours in media with varied osmolarity that resulted from alterations in NaCl and sorbitol content. The viability of experimental embryos cultured to advanced stages was determined by comparison with that of the controls, noncultured embryos transferred to recipient gilts. The data suggest that variation in embryonic development in the experimental media is related to the NaCl concentration rather than to osmolarity. Increased NaCl concentration impairs development of the embryos to the advanced morula/blastocyst stages (P<0.001). There was no difference in the pregnancy rate between the recipients of cultured (45%) and noncultured (57%) embryos on Day 25. There was, however, a higher embryonic survival rate (P<0.05) within the control gilts.

13.
J Clin Endocrinol Metab ; 96(2): E360-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21177793

RESUMO

CONTEXT: Sex steroids play a central role in breast cancer development. OBJECTIVE: This study aimed to relate polymorphic variants in 36 candidate genes in the sex steroid pathway to serum concentrations of sex steroid hormones and SHBG. DESIGN: Data on 700 genetic polymorphisms were combined with existing hormone assays and data on breast cancer incidence, within the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Nurses' Health Study (NHS) cohorts; significant findings were reanalyzed in the Multiethnic Cohort (MEC). SETTING AND PARTICIPANTS: We analyzed data from a pooled sample of 3852 pre- and postmenopausal Caucasian women from EPIC and NHS and 454 postmenopausal women from MEC. MAIN OUTCOME MEASURES: Outcome measures were SHBG, testosterone, dehydroepiandrosterone (DHEAS), androstenedione, estrone (E1), and estradiol (E2) as well as breast cancer risk. RESULTS: Globally significant associations were found among pre- and postmenopausal women combined between levels of SHBG and the SHBG gene and between DHEAS and the FSHR and AKR1C3 genes. Among postmenopausal women, serum E1 and E2 were significantly associated with the genes CYP19 and FSHR, and E1 was associated with ESR1. None of the variants related to serum hormone levels showed any significant association with breast cancer risk. CONCLUSIONS: We confirmed associations between serum levels of SHBG and the SHBG gene and of E1 and E2 and the CYP19 and ESR1 genes. Novel associations were observed between FSHR and DHEAS, E1, and E2 and between AKR1C3 and DHEAS.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Hormônios/genética , Hormônios/metabolismo , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Esteroides/metabolismo , Fatores Etários , Idoso , Alelos , Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Estudos de Coortes , Etnicidade , Europa (Continente)/epidemiologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Hormônios Esteroides Gonadais/genética , Hormônios Esteroides Gonadais/metabolismo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco
14.
Physiol Meas ; 31(2): 233-47, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20086274

RESUMO

Textile electrodes and conductors are being developed and used in different monitoring scenarios, such as ECG or bioimpedance spectroscopy measurements. Compared to standard materials, conductive textile materials offer improved wearing comfort and enable long-term measurements. Unfortunately, the development and investigation of such materials often suffers from the non-reproducibility of the test scenarios. For example, the materials are generally tested on human skin which is difficult since the properties of human skin differ for each person and can change within hours. This study presents two test setups which offer reproducible measurement procedures for the systematic analysis of textile electrodes and conductors. The electrode test setup was designed with a special skin dummy which allows investigation of not only the electrical properties of textile electrodes but also the contact behavior between electrode and skin. Using both test setups, eight textile electrodes and five textile conductors were analyzed and compared.


Assuntos
Eletrodos , Eletrônica Médica/instrumentação , Têxteis , Algoritmos , Impedância Elétrica , Eletricidade , Humanos , Fenômenos Mecânicos , Modelos Biológicos , Fotoperíodo , Reprodutibilidade dos Testes , Fenômenos Fisiológicos da Pele , Fatores de Tempo
15.
Leukemia ; 29(4): 981-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25376373
16.
Artigo em Inglês | MEDLINE | ID: mdl-19964634

RESUMO

During physical exercise body muscles are activated and heat is generated. In intensive physical activity, heat will be released by sweating to protect the body of overheating. Sweating and convection implies a water loss which can lead to dehydration. To avoid health problems as a result of dehydration, the body water content can be monitored to detect changes early in order to rehydrate in time. Bioimpedance Spectroscopy (BIS) is a comfortable measurement method to monitor the body composition under controlled conditions, that is used for different applications, like monitoring dialysis. Unfortunately, the physiological changes due to sportive activities can influence the BIS and complicate the measurement. In this article, a study is presented in which the fluid content of five test persons is monitored during physical exercise, whereas all test persons did not drink anything before and during sport. During training not only the body composition was measured using a BIS device but also the skin temperature was monitored with an infrared camera. As a result, it could be shown that such a combination of measurement systems allow to use BIS devices also during sport as significant monitoring systems for detecting a person's body fluid loss.


Assuntos
Água Corporal , Esforço Físico/fisiologia , Análise Espectral/métodos , Adulto , Impedância Elétrica , Feminino , Humanos , Masculino , Fenômenos Fisiológicos da Pele , Temperatura Cutânea
17.
Genes Immun ; 7(8): 615-24, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16971956

RESUMO

Interactions between environment and immune system play an essential role in the aetiology of immunopathologies, including lymphomas. Toll-like receptors (TLR) belong to a group of pattern recognition receptors, with importance for innate immune response and inflammatory processes. Interleukin-10 (IL-10) is a key regulatory cytokine and has been implicated in lymphomagenesis. Functional polymorphisms in these inflammation-associated genes may affect the susceptibility towards lymphoma. To test this hypothesis, we have genotyped DNA of 710 lymphoma cases and 710 controls within the context of a population-based epidemiological study for 11 functionally important single-nucleotide polymorphisms in TLR1, -2, -4, -5, -9, IL10 and IL10 receptor (IL10RA). The IL10RA Ser138Gly variant was underrepresented among lymphoma cases (odds ratio (OR)=0.81, 95 per cent confidence interval (95% CI)=0.65-1.02), mainly owing to an inverse association with Hodgkin's lymphoma (HL). The TLR2 -16933T>A variant was associated with a 2.8-fold increased risk of follicular lymphoma (95% CI=1.43-5.59) and a decreased risk of chronic lymphocytic leukaemia (OR=0.61, 95% CI=0.38-0.95). Furthermore, the TLR4 Asp299Gly variant was positively associated with the risk of mucosa-associated lymphoid tissue lymphoma (OR=2.76, 95% CI=1.12-6.81) and HL (OR=1.80, 95% CI=0.99-3.26). In conclusion, this study suggests an effect of polymorphisms in factors of the innate immune response in the aetiology of some lymphoma subtypes.


Assuntos
Predisposição Genética para Doença , Imunidade Inata/genética , Subunidade alfa de Receptor de Interleucina-10/genética , Interleucina-10/genética , Linfoma/genética , Polimorfismo de Nucleotídeo Único , Receptores Toll-Like/genética , Adulto , Idoso , Feminino , Genótipo , Alemanha/epidemiologia , Haplótipos/genética , Humanos , Linfoma/epidemiologia , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances
18.
Anaesth Intensive Care ; 33(6): 762-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16398382

RESUMO

A survey was posted to all New South Wales and Provisional Fellows of the Australian and New Zealand College of Anaesthetists to assess the influence of the current medicolegal climate on their anaesthetic practice. Information collected included demographics, opinions regarding the current medico-legal climate, medical defence organizations, and the implications for anaesthetic practice. The response rate was 78% (640/820). Nearly all (95.3%) were concerned about the current medical indemnity crisis and 80.5% felt concerned about the financial security of medical insurers. Of all these respondents 23.6% had personal experience of litigation and 73.6% expected to have a claim made against them during their career: Respondents spent an average of 8.3% of their gross annual income on medical insurance premiums and 47.2% are concerned about the viability of their practice given the rising costs of medical insurance. Obstetric anaesthesia was the most common area of practice to be ceased due to medicolegal concerns. In the next two years, 20.2% of obstetric anaesthetists who responded intend to cease practice. In the past two years, 3.1% of respondents retired due to their litigation concerns, while 12.8% (average age 56.7y) are intending to retire in the next two years for the same reasons. Changes to the conduct of the preoperative consultation were common. Other changes to practice included more thorough documentation of complications (50.8%) and a strong reluctance to perform neuraxial blocks (54%). This survey suggests that anaesthetists are concerned about the current medicolegal climate and as a result, some are retiring earlier and giving up high-risk areas of practice.


Assuntos
Anestesia/métodos , Anestesiologia/legislação & jurisprudência , Seguro de Responsabilidade Civil , Imperícia/legislação & jurisprudência , Gestão da Qualidade Total , Anestesiologia/economia , Atitude do Pessoal de Saúde , Mobilidade Ocupacional , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Seguro de Responsabilidade Civil/economia , Responsabilidade Legal , Masculino , Auditoria Médica , New South Wales , Padrões de Prática Médica , Inquéritos e Questionários
19.
Bioinformatics ; 21(14): 3183-4, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15879457

RESUMO

SDMinP is an easy-to-use program for fast calculation of empirical and adjusted P-values for correlated and uncorrelated hypotheses in multiple testing experiments. It is based on the Free Step-Down Resampling Method for controlling the family wise error rate, and implements a variation of an efficient algorithm, which reduces the originally required re-sampling effort considerably and makes the method computationally feasible. The program is independent of the underlying test statistic and works with provided observed and permutation test statistics.


Assuntos
Algoritmos , Interpretação Estatística de Dados , Modelos Biológicos , Software , Simulação por Computador , Tamanho da Amostra
20.
Eur Spine J ; 14(8): 752-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16133078

RESUMO

UNLABELLED: This biomechanical study was performed to test the primary segmental in vitro stabilising effect of a standard and large footprint radiolucent poly-ether-ether-ketone (PEEK) box cage versus a titanium box cage for anterior lumbar interbody fusion. Eighteen L2-L3 and sixteen L4-L5 cadaveric motion segments were divided into three groups and received a titanium cage or a radiolucent PEEK cage with standard or large footprint. All specimens were tested in three testing conditions: intact, stand-alone anterior cage and finally with supplemental translaminar screw fixation. Full range of motion and neutral zone measurements were determined and anterior cage pull out force was tested. The titanium design was significantly more effective in reducing the range of motion only in axial rotation. The larger footprint radiolucent cage did not increase stability as compared to the standard footprint. The titanium cage pull out force was significantly (P=0.0002) higher compared to both radiolucent cage constructs. CLINICAL RELEVANCE: Supplemental posterior fixation is strongly recommended to increase initial stability of any anterior interbody fusion cage construct. Although the biomechanical stability necessary to achieve spinal fusion is not defined, the radiolucent designs tested in this study, with a standard footprint as well as with a larger footprint, may be insufficiently stabilised with translaminar screws as compared to the titanium implant. Supplemental pedicle screw fixation may be required to obtain adequate stabilisation in the clinical setting.


Assuntos
Fixadores Internos , Cetonas , Vértebras Lombares/cirurgia , Polietilenoglicóis , Fusão Vertebral , Titânio , Benzofenonas , Cadáver , Feminino , Humanos , Implantes Experimentais , Vértebras Lombares/patologia , Masculino , Teste de Materiais , Polímeros , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Estresse Mecânico
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