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1.
EMBO J ; 42(10): e111806, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36988334

RESUMO

Spatially organized reaction dynamics between proto-oncogenic epidermal growth factor receptor (EGFR) and protein tyrosine phosphatases determine EGFR phosphorylation dynamics in response to growth factors and thereby cellular behavior within developing tissues. We show that the reaction dynamics of mutual inhibition between RPTPγ phosphatase and autocatalytic ligandless EGFR phosphorylation enable highly sensitive promigratory EGFR signaling responses to subnanomolar EGF levels, when < 5% receptors are occupied by EGF. EGF thereby triggers an autocatalytic phospho-EGFR reaction by the initial production of small amounts of phospho-EGFR through transient, asymmetric EGF-EGFR2 dimers. Single cell RPTPγ oxidation imaging revealed that phospho-EGFR induces activation of NADPH oxidase, which in turn inhibits RPTPγ-mediated dephosphorylation of EGFR, tilting the autocatalytic RPTPγ/EGFR toggle switch reaction towards ligandless phosphorylated EGFR. Reversibility of this reaction to EGF is maintained by the constitutive phosphatase activity of endoplasmic reticulum-associated TCPTP. This RPTPγ/EGFR reaction at the plasma membrane causes promigratory signaling that is separated from proliferative signaling induced by accumulated, liganded, phosphorylated EGF-EGFR in endosomes. Accordingly, loss of RPTPγ results in constitutive promigratory signaling from phosphorylated EGFR monomers. RPTPγ is thus a suppressor of promigratory oncogenic but not of proliferative EGFR signaling.


Assuntos
Fator de Crescimento Epidérmico , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo , Receptores ErbB/metabolismo , Transdução de Sinais , Fosforilação , Oxirredução
2.
Angew Chem Int Ed Engl ; 62(49): e202309498, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37786992

RESUMO

Here, we show the conversion of unactivated alkenes into α-branched enones via regioselective chloroacylation with acyl chlorides. The method relies upon the initial in situ generation of chlorine radicals directly from the acyl chloride precursor under cooperative nickel/photoredox catalysis. Subsequent HCl elimination provides enones and α,ß-unsaturated esters that are not accessible via the conventional acylation approaches that provide the other, linear constitutional isomer.

3.
BMC Med Educ ; 18(1): 85, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29716611

RESUMO

BACKGROUND: Evaluation of two different self-educational methods (video assisted learning versus video assisted learning plus a nodal point operation primer) on learning laparoscopic suturing and intracorporal knotting. METHODS: Randomized controlled trial at the laparoscopic surgical training center, University of Tubingen with 45 surgical novices first year medical students being pretested for dexterity. After self-educational training for 90 min with either method (Group A: video assisted learning, Group B: video assisted learning plus a nodal point operation primer) participants had to perform five laparoscopic intracorporal knots. Assessed were number of knots completed (maximum of five knots counted, knot integrity, technical proficiency and knotting time per knot. Primary outcome measure is a composed knot score combining knot integrity, technical proficiency and knotting time. RESULTS: Group B (n = 23) achieved a significantly higher composed knot score than Group A (n = 22) (53.3 ± 8.4 versus 46.5 ± 13.6 points respectively, p = 0.016). Median knotting time per completed knot was significantly different between Group B and Group A (308 s [100-1221] versus 394 s [138-1397] respectively, p = 0.001). Concerning number of completed knots there was a trend towards more knots achieved in Group B (4.2 ± 1.2 versus 3.55 ± 1.4 respectively, p = 0.075) . CONCLUSIONS: The use of a nodal point operation primer highlighting essential key steps of a procedure augment the success of learning laparoscopic skills as suturing and intracorporal knotting. (UIN researchregistry3866, March 22, 2018).


Assuntos
Recursos Audiovisuais , Laparoscopia/educação , Destreza Motora , Autoaprendizagem como Assunto , Estudantes de Medicina , Técnicas de Sutura/educação , Adulto , Competência Clínica , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Fatores de Tempo , Adulto Jovem
4.
J Neurooncol ; 130(3): 439-448, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27619981

RESUMO

Tissue inhibitor of metalloproteinases-1 (TIMP-1) has been associated with poor prognosis and resistance towards chemotherapy in several cancer forms. In a previous study we found an association between a low TIMP-1 tumor immunoreactivity and increased survival for glioblastoma patients, when compared to moderate and high TIMP-1 tumor immunoreactivity. The aim of the present study was to further evaluate TIMP-1 as a biomarker in gliomas by studying TIMP-1 gene copy numbers by fluorescence in situ hybridization (FISH) on 33 glioblastoma biopsies and by measuring levels of TIMP-1 in plasma obtained pre-operatively from 43 patients (31 gliomas including 21 glioblastomas) by enzyme-linked immunosorbent assay (ELISA). The results showed TIMP-1 gene copy numbers per cell ranging from 1 to 5 and the TIMP-1/CEN-X ratio ranging between 0.7 and 1.09, suggesting neither amplification nor loss of the TIMP-1 gene. The TIMP-1 protein levels measured in plasma were not significantly higher than TIMP-1 levels measured in healthy subjects. No correlation was identified between TIMP-1 tumor cell immunoreactivities and the TIMP-1 gene copy numbers or the plasma TIMP-1 levels. In conclusion, high immunohistochemical TIMP-1 protein levels in glioblastomas were not caused by TIMP-1 gene amplification and TIMP-1 in plasma was low and not directly related to tumor TIMP-1 immunoreactivity. The study suggests that TIMP-1 immunohistochemistry is the method of choice for future clinical studies evaluating TIMP-1 as a biomarker in glioblastomas.


Assuntos
Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/genética , Glioblastoma/sangue , Glioblastoma/genética , Inibidor Tecidual de Metaloproteinase-1/sangue , Inibidor Tecidual de Metaloproteinase-1/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Variações do Número de Cópias de DNA , Dinamarca , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise Serial de Tecidos
5.
World J Surg ; 40(12): 2888-2891, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27431317

RESUMO

BACKGROUND: Clinical pathways aim to standardize perioperative and postoperative care of surgical procedures and are shown to result in a significant optimization associated with cost reduction. The aim of this study was to establish the impact of two different implementations forms of clinical pathways on the pathway compliance and resulting costs. METHODS: Data of patients undergoing elective cholecystectomy for symptomatic cholecystolithiasis were collected over two different periods: using a clinical pathway in the form of a paper-based checklist, or a clinical pathway integrated into the paper-based medical treatment and nursing documentation. Outcome measures were compliance of the clinical pathway and total costs per case. RESULTS: The compliance was significantly higher using integrated pathways compared to paper-based checklists (n = 117 of 123, 95 % vs 54 of 118, 46 %; p < 0.001). Mean total costs (€2206 vs €2458, p = 0.027) and length of hospital stay (2.13 vs 2.77 days, p < 0.001) were significantly reduced by the integrated clinical pathway compared to checklists. Further, the variation of costs per case and variation of length of hospital stay were significantly smaller with integrated clinical pathway (±€440 vs ±€538, p = 0.039 and ±0.53 vs ±0.68 days, p < 0.001, respectively). No difference regarding postoperative complication was observed (n = 3 vs. 4 events; p = 0.67). CONCLUSION: Integrated clinical pathways display a significant higher compliance compared to checklists resulting in reduced total costs, shorter hospital stay and a smaller variation of cost, making it a useful tool in process controlling and planning.


Assuntos
Colecistectomia Laparoscópica , Procedimentos Clínicos , Procedimentos Cirúrgicos Eletivos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
6.
World J Surg Oncol ; 13: 338, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26684213

RESUMO

BACKGROUND: Rapid growth of thyroid nodules is described as being associated with thyroid cancer. The objective of the study was to determine how the growth rate of thyroid nodules during follow-up is associated with the risk of thyroid cancer. METHODS: Retrospective analysis of patients undergoing thyroid surgery for nodular disease and a repetitive preoperative ultrasound work-up of at least 6 months was done. Nodule growth was considered relevant when a volume increase >49% was detected. Growth patterns were described as rapid for a volume increase present over 6 to 24 months. RESULTS: Of the 297 analysed patients, 226 (76%) displayed relevant nodule growth and 71 (24%) no relevant growth. A rapid growth pattern was seen in 73 patients (32%). Well-differentiated thyroid cancer was diagnosed in 33 patients (11%; 27 papillary, 6 follicular) with a relevant nodule growth in 2 and no relevant growth in 31 patients. No rapid growth pattern was observed in any case of well-differentiated thyroid cancer. A rapid growth pattern occurred only in benign nodules (70 patients) and in 1 patient each with a lymphoma, a metastasis of a renal cell cancer and a metastasis of a gastric adenocarcinoma. Therapy with levothyroxine and/or iodine was administered to 129 patients (43%) and was significantly inversely correlated with nodule growth (odds ratio 0.27; CI 95 % 0.14-0.53, p < 0.001). CONCLUSIONS: Thyroid nodule growth alone and especially a rapid growth pattern during follow-up for thyroid nodular disease is not a marker for well-differentiated thyroid cancer and should not be used as a stand-alone argument for thyroid surgery.


Assuntos
Adenocarcinoma Folicular/secundário , Adenocarcinoma/secundário , Carcinoma Papilar/secundário , Diferenciação Celular , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma Folicular/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/cirurgia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/cirurgia , Adulto Jovem
7.
Emerg Med J ; 32(9): 698-702, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25476715

RESUMO

BACKGROUND: Hyperbilirubinaemia is reported to be a positive predictor in diagnosing appendicitis and especially appendiceal perforation. We, therefore, analysed the diagnostic accuracy of serum bilirubin in anticipating appendicitis and its severity. METHODS: All consecutive patients undergoing appendectomy for suspected appendicitis from May 2009 to August 2011 were analysed. Patients were classified based on final histopathological findings into the groups: no appendiceal inflammation, non-perforated appendicitis and perforated appendicitis. Primary outcome was the diagnostic accuracy of serum bilirubin levels in discriminating between no appendiceal inflammation and any appendicitis (perforated and non-perforated appendicitis) and non-perforated and perforated appendicitis. RESULTS: Of 493 analysed patients, 125 (25%) had no appendiceal inflammation, 312 (64%) had non-perforated appendicitis and 56 (11%) had perforated appendicitis. The proportion of patients with bilirubin elevation (>1.1 mg/dL) was different between those with no appendiceal inflammation (14%) and any appendicitis (36%) (p<0.0001), and between non-perforated appendicitis and perforated appendicitis 48% (p=0.04). However, the positive and negative likelihood ratios (LRs) for an elevated bilirubin were poor at discriminating the groups: no appendiceal inflammation versus any appendicitis (LR+ 2.62 (95% CI 1.65 to 4.16) and LR- 0.75 (95% CI 0.67 to 0.83)) and non-perforated appendicitis versus perforated appendicitis (LR+ estimate 1.74 (95% CI 1.28 to 2.38) and LR- 0.72 (95% CI 0.55 to 0.93)). CONCLUSIONS: Hyperbilirubinaemia is present in acute appendicitis but has a low diagnostic accuracy in discriminating between any appendicitis versus no appendiceal inflammation and perforated versus non-perforated appendicitis and is, therefore, of limited value in clinical routine. TRIAL REGISTRATION NUMBER: NCT01698099.


Assuntos
Apendicite/sangue , Apendicite/patologia , Bilirrubina/sangue , Hiperbilirrubinemia/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apendicectomia , Apendicite/cirurgia , Feminino , Humanos , Hiperbilirrubinemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Adulto Jovem
8.
Nanotechnology ; 25(11): 115303, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24561614

RESUMO

Low energy ion beam pattern formation on Si with simultaneous co-deposition of Ag, Pd, Pb, Ir, Fe or C impurities was investigated by in situ scanning tunneling microscopy as well as ex situ atomic force microscopy, scanning electron microscopy, transmission electron microscopy and Rutherford backscattering spectrometry. The impurities were supplied by sputter deposition. Additional insight into the mechanism of pattern formation was obtained by more controlled supply through e-beam evaporation. For the situations investigated, the ability of the impurity to react with Si, i.e. to form a silicide, appears to be a necessary, but not a sufficient condition for pattern formation. Comparing the effects of impurities with similar mass and nuclear charge, the collision kinetics is shown to be not of primary importance for pattern formation. To understand the observed phenomena, it is necessary to assume a bi-directional coupling of composition and height fluctuations. This coupling gives rise to a sensitive dependence of the final morphology on the conditions of impurity supply. Because of this history dependence, the final morphology cannot be uniquely characterized by a steady state impurity concentration.

9.
BMC Cancer ; 13: 489, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24144331

RESUMO

BACKGROUND: Platinum-based chemotherapy has long been used in the treatment of a variety of cancers and functions by inducing DNA damage. ERCC1 and ERCC4 are involved in the removal of this damage and have previously been implicated in resistance to platinum compounds. The aim of the current investigation is to determine the presence, frequency and prognostic impact of ERCC1 or ERCC4 gene copy number alterations in colorectal cancer (CRC). METHODS: Fluorescent in situ hybridization probes directed at ERCC1 and ERCC4 with relevant reference probes were constructed. Probes were tested in a CRC cell line panel and in tumor sections from 152 stage III CRC chemonaive patients. Relationships between biomarker status and clinical endpoints (overall survival, time to recurrence, and local recurrence in rectal cancer) were analyzed by survival statistics. RESULTS: ERCC1-19q13 copy number alterations were observed in a single cell line metaphase (HT29). In patient material, ERCC1-19q13 copy number gains (ERCC1-19q13/CEN-2 ≥ 1.5) were detected in 27.0% of specimens, whereas ERCC1-19q13 deletions (ERCC1-19q13/CEN-2 < 0.8) were only detected in 1.3%. ERCC1-19q13 gain was significantly associated with longer survival (multivariate analysis, HR: 0.45, 95% CI: 0.20-1.00, p = 0.049) in patients with colon tumors, but not rectal tumors. No ERCC4 aberrations were detected and scoring was discontinued after 50 patients. CONCLUSIONS: ERCC1-19q13 copy number gains occur frequently in stage III CRC and influences survival in patients with colon tumors. Future studies will investigate the effect of ERCC1-19q13 aberrations in a platinum-treated patient population with the aim of developing a predictive biomarker profile for oxaliplatin sensitivity in CRC.


Assuntos
Cromossomos Humanos Par 19 , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Fatores Etários , Linhagem Celular Tumoral , Aberrações Cromossômicas , Estudos de Coortes , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Fatores Sexuais
10.
Trials ; 24(1): 76, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726155

RESUMO

BACKGROUND: Incisional hernia is a frequent complication following loop ileostomy reversal. Incisional hernias are associated with morbidity, loss of health-related quality of life and costs and warrant the investigation of prophylactic measures. Prophylactic mesh implantation at the time of surgical stoma reversal has shown to be a promising and safe method to prevent incisional hernias in this setting. However, the efficacy of this method has not yet been investigated in a large multicentre randomised-controlled trial (RCT) with adequate external validity. The P.E.L.I.O.N. trial will evaluate the efficacy of prophylactic mesh reinforcement after loop ileostomy closure in decreasing the rate of incisional hernia versus standard closure alone. METHODS: P.E.L.I.O.N. is a multicentre, patient- and observer-blind RCT. Patients undergoing loop ileostomy closure will undergo intraoperative 1:1 randomisation into either abdominal wall closure with a continuous slowly absorbable suture in small-stitch technique without mesh reinforcement (control group) or abdominal wall closure with an additional reinforcement with a retromuscular non-absorbable, macro-pore (pore size ≥ 1000 µm or effective porosity >0%) light-weight monofilament or mixed structure mesh. A total of 304 patients (152 per group) will need to be randomised in the study. Based on inclusion and exclusion criteria, 1,014 patients are expected to be screened for eligibility in order to recruit the necessary number of patients. The primary endpoint will be the frequency of incision hernias within 24 months according to the European Hernia Society definition. Secondary endpoints will be the frequency of surgical site occurrences (including surgical site infections, wound seromas and hematomas, and enterocutaneous fistulas), postoperative pain, the number of revision surgeries and health-related quality of life. Safety will be assessed by measuring postoperative complications ≥ grade 3 according to the Dindo-Clavien classification. DISCUSSION: Depending on the results of the P.E.L.I.O.N. trial, prophylactic mesh implantation could become the new standard for loop ileostomy reversal. TRIAL REGISTRATION: DRKS00027921, U1111-1273-4657.


Assuntos
Técnicas de Fechamento de Ferimentos Abdominais , Hérnia Incisional , Estomas Cirúrgicos , Humanos , Hérnia Incisional/etiologia , Hérnia Incisional/prevenção & controle , Ileostomia/efeitos adversos , Telas Cirúrgicas/efeitos adversos , Incidência , Técnicas de Fechamento de Ferimentos Abdominais/efeitos adversos
11.
J Surg Res ; 173(1): 68-74, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20934714

RESUMO

BACKGROUND AND OBJECTIVE: Key factors of Fast Track (FT) programs are fluid restriction and epidural analgesia (EDA). We aimed to challenge the preconception that the combination of fluid restriction and EDA might induce hypotension and renal dysfunction. METHODS: A recent randomized trial (NCT00556790) showed reduced complications after colectomy in FT patients compared with standard care (SC). Patients with an effective EDA were compared with regard to hemodynamics and renal function. RESULTS: 61/76 FT patients and 59/75 patients in the SC group had an effective EDA. Both groups were comparable regarding demographics and surgery-related characteristics. FT patients received significantly less i.v. fluids intraoperatively (1900 mL [range 1100-4100] versus 2900 mL [1600-5900], P < 0.0001) and postoperatively (700 mL [400-1500] versus 2300 mL [1800-3800], P < 0.0001). Intraoperatively, 30 FT compared with 19 SC patients needed colloids or vasopressors, but this was statistically not significant (P = 0.066). Postoperative requirements were low in both groups (3 versus 5 patients; P = 0.487). Pre- and postoperative values for creatinine, hematocrit, sodium, and potassium were similar, and no patient developed renal dysfunction in either group. Only one of 82 patients having an EDA without a bladder catheter had urinary retention. Overall, FT patients had fewer postoperative complications (6 versus 20 patients; P = 0.002) and a shorter median hospital stay (5 [2-30] versus 9 d [6-30]; P< 0.0001) compared with the SC group. CONCLUSIONS: Fluid restriction and EDA in FT programs are not associated with clinically relevant hemodynamic instability or renal dysfunction.


Assuntos
Analgesia Epidural , Anestésicos Combinados , Colectomia , Hidratação , Rim/fisiologia , Assistência Perioperatória , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Contraindicações , Feminino , Hemodinâmica/fisiologia , Humanos , Incidência , Infusões Intravenosas , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos
12.
Scand J Gastroenterol ; 47(1): 68-79, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22171973

RESUMO

OBJECTIVE: A positive relationship between topoisomerase-1 (TOP1) protein and sensitivity toward the TOP1 inhibitor irinotecan has been reported in patients with metastatic colorectal cancer (mCRC). In this study, we analyzed TOP1 gene copy number variation in tumor tissue from CRC patients and CRC cell lines with different sensitivities to the TOP1 inhibitor SN-38 and oxaliplatin. MATERIAL AND METHODS: A TOP1 gene probe with a chromosome 20 centromere (CEN-20) reference probe was applied on normal mucosa and on tumor tissue from 50 stage III CRC patients. Additionally, associations between TOP1/CEN-20 ratio and in vitro sensitivity to SN-38 (irinotecan) and oxaliplatin were tested on 10 CRC cell lines. Results. In the malignant epithelium, 84% of the samples demonstrated an increased TOP1 gene copy number and 64% had an increased TOP1/CEN-20 ratio compared with the non-affected mucosa. Sixteen (32%) of the tumors had a ratio of ≥ 1.5 and 9 (18%) of these had a ratio of ≥ 2.0. A positive association was observed between the TOP1 gene copy number and the TOP1/CEN-20 ratio and in vitro sensitivity toward SN-38, but not toward oxaliplatin. CONCLUSIONS: A large fraction of the clinical samples demonstrated increased TOP1 gene copy number and increased TOP1/CEN-20 ratio. The cell line study suggested an association between TOP1 gene copy number or TOP1/CEN-20 ratio and sensitivity to irinotecan but not oxaliplatin.


Assuntos
Neoplasias Colorretais/genética , DNA Topoisomerases Tipo I/genética , Resistencia a Medicamentos Antineoplásicos/genética , Dosagem de Genes , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hibridização in Situ Fluorescente , Irinotecano , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Estatísticas não Paramétricas
13.
Dig Surg ; 29(3): 183-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22677649

RESUMO

BACKGROUND AND AIM: In up to 3% of laparoscopic cholecystectomies, procedure-related complications occur. Routine postoperative ultrasound is one means of screening for these complications. The aim of this study was to determine the utility of this practice after laparoscopic cholecystectomy. METHODS: A series of consecutive patients (n = 1,044) undergoing laparoscopic cholecystectomy from January 2007 to January 2011 was analysed. Primary endpoint was the detection of procedure-related complications by routine ultrasound. RESULTS: Routine ultrasound within the first 48 h after laparoscopic cholecystectomy was performed in 967 of 1,044 patients. Overall, 25 (2.4%) of the 1,044 patients suffered from procedure-related complications, but only in 2 patients was the complication detected by routine ultrasound. Findings were false-positive in 103 patients. This corresponds to a sensitivity of 8% and a specificity of 89%. Hospital stay was prolonged in the false-positive group. CONCLUSION: Routine postoperative ultrasound has a low sensitivity for the detection of complications after laparoscopic cholecystectomy. In almost all cases, the diagnosis is initiated by clinical findings. Therefore, routine ultrasound is of limited value in screening for postoperative complications after cholecystectomy.


Assuntos
Abscesso Abdominal/diagnóstico por imagem , Ductos Biliares/diagnóstico por imagem , Ductos Biliares/lesões , Colecistectomia Laparoscópica/efeitos adversos , Coledocolitíase/diagnóstico por imagem , Hemorragia Pós-Operatória/diagnóstico por imagem , Abscesso Abdominal/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Coledocolitíase/etiologia , Reações Falso-Positivas , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Sensibilidade e Especificidade , Fatores de Tempo , Ultrassonografia , Adulto Jovem
14.
BMC Clin Pathol ; 12: 3, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22333181

RESUMO

BACKGROUND: Chromogenic in situ hybridization (CISH) is fast becoming a well established technique for easy and sensitive determination of HER2 gene status in breast cancer. However, for the chromogenic method to achieve status as a safe and reliable technique, the method needs to be validated against already known and validated FISH techniques. METHODS: Here it is reported from a comparative study where HER2 gene status obtained by HER2 CISH pharmDx™ Kit was compared to HER2 gene status obtained by the FDA approved HER2 FISH pharmDx™ Kit and the PathVysion HER-2 DNA probe Kit. The study included 365 formalin fixed and paraffin-embedded invasive breast cancer tissue specimens collected consecutively at a US reference laboratory. RESULTS: The data obtained revealed an overall HER2 status concordance of approximately 98% for comparisons of HER2 CISH pharmDx™ Kit to both HER2 FISH pharmDx™ Kit and PathVysion HER-2 DNA Probe Kit. CONCLUSIONS: The concordance between results obtained using the recently FDA approved HER2 CISH pharmDx™ Kit with previously FDA approved FISH techniques for HER2 gene status determination indicate that the HER2 CISH pharmDx™ Kit is a reliable chromogenic alternative to fluorescence-based methods.

15.
World J Surg Oncol ; 10: 264, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23231927

RESUMO

BACKGROUND: Vasoactive intestinal polypeptide secreting tumors(VIPomas) are rare endocrine tumors of the pancreas with an estimated incidence of 0.1 per million per year. The molecular mechanisms that mediate development of VIPomas are poorly investigated and require definition. METHODS: A genome- and gene expression analysis of specimens of a primary pancreatic VIPoma with hepatic metastases was performed. The primary tumor, the metastases, the corresponding healthy tissue of the liver, and the pancreas were compared with each other using oligonucleotide microarrays and loss of heterozygosity (LOH). RESULTS: The results revealed multiple LOH events and several differentially expressed genes. Our finding of LOH and downregulation was conspicuous in the microarray analysis for the mismatch repair gene MSH2 in the primary pancreatic VIPoma tumor, the hepatic metastasis but not in the corresponding healthy tissue. Further a strong overexpression of the chemokine CXCR4 was detected in the hepatic metastases compared to its pancreatic primary. With a review of the literature we describe the molecular insights of metastatic development in VIPoma. CONCLUSION: In VIPoma, defects in the mismatch repair system especially in MSH2 may contribute to carcinogenesis, and increased CXCR4 may be associated with liver metastasis.


Assuntos
Proteína 2 Homóloga a MutS/fisiologia , Neoplasias Pancreáticas/genética , Receptores CXCR4/fisiologia , Vipoma/genética , Idoso , Reparo de Erro de Pareamento de DNA/genética , Humanos , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites , Proteína 2 Homóloga a MutS/genética , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/patologia , Receptores CXCR4/genética , Vipoma/etiologia , Vipoma/patologia
16.
Nano Lett ; 11(6): 2304-10, 2011 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-21608990

RESUMO

The fabrication of three-dimensional assemblies consisting of large quantities of nanowires is of great technological importance for various applications including (electro-)catalysis, sensitive sensing, and improvement of electronic devices. Because the spatial distribution of the nanostructured material can strongly influence the properties, architectural design is required in order to use assembled nanowires to their full potential. In addition, special effort has to be dedicated to the development of efficient methods that allow precise control over structural parameters of the nanoscale building blocks as a means of tuning their characteristics. This paper reports the direct synthesis of highly ordered large-area nanowire networks by a method based on hard templates using electrodeposition within nanochannels of ion track-etched polymer membranes. Control over the complexity of the networks and the dimensions of the integrated nanostructures are achieved by a modified template fabrication. The networks possess high surface area and excellent transport properties, turning them into a promising electrocatalyst material as demonstrated by cyclic voltammetry studies on platinum nanowire networks catalyzing methanol oxidation. Our method opens up a new general route for interconnecting nanowires to stable macroscopic network structures of very high integration level that allow easy handling of nanowires while maintaining their connectivity.


Assuntos
Nanofios/química , Platina/química , Catálise , Eletroquímica , Metanol/química , Oxirredução , Tamanho da Partícula , Polímeros/química , Teoria Quântica , Propriedades de Superfície
17.
Chem Commun (Camb) ; 58(77): 10809-10812, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36069397

RESUMO

Pd-catalyzed alkenylations of metallocenes via C-H activation were developed using electronically tunable pyrazolonaphthyridine (PzNPy) ligands. Ferrocene was alkenylated using the most electron-deficient ligand in the series, whereas the less reactive ruthenocene needed balancing of the electrophilicity and stability of catalysts. Various alkenes were installed, allowing fine-tuning of redox potentials.


Assuntos
Alcenos , Paládio , Compostos Ferrosos , Ligantes , Metalocenos , Compostos Organometálicos
18.
Breast Cancer Res Treat ; 127(2): 345-55, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20556506

RESUMO

The estrogen receptor (ER) is the target of tamoxifen, but endocrine therapies do not benefit all patients with ER positive tumors. We therefore hypothesized that copy number changes in the ESR1 gene, encoding ER, confer resistance. Within a consecutive series of ER positive, postmenopausal patients allocated to 5 years tamoxifen, we identified 61 patients with recurrence less than 4 years and 48 patients without recurrence at least 7 years after initiation of adjuvant tamoxifen. Archival tissue containing primary tumor was collected from 97 patients (89%). Tumor samples were analyzed for ESR1 copy number changes using FISH with a probe covering the ESR1 gene at 6q25 and a reference probe covering the centromere of chromosome 6. The assay was validated in a material of 120 normal breast samples. FISH analysis for ESR1 was successful in 91 patients (94%). Amplification (ratio ESR1/CEN-6 ≥ 2.0) was observed in 11 of 50 (22%) patients with early recurrence, compared to two of 41 (5%) patients without recurrence. The difference is statistically significant (P = 0.033). In both groups, two patients with ESR1 deletion (ratio ESR1/CEN-6 < 0.8) were identified. ESR1 amplification was significantly associated with poor disease-free survival (P = 0.0054) and overall survival (P = 0.0004). This pilot study supports our hypothesis that ESR1 amplification is associated with a poorer outcome following adjuvant treatment with tamoxifen in ER positive early breast cancer. This study also revealed the existence of ESR1 deletions. The prognostic and predictive impact of ESR1 copy number changes needs further exploration in clinical trials.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Amplificação de Genes/genética , Pós-Menopausa , Tamoxifeno/uso terapêutico , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Quimioterapia Adjuvante , Feminino , Deleção de Genes , Ordem dos Genes , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Análise de Sobrevida
19.
Sci Rep ; 11(1): 14802, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285304

RESUMO

A key challenge to advance the efficiency of bioprocesses is the uncoupling of biomass from product formation, as biomass represents a by-product that is in most cases difficult to recycle efficiently. Using the example of rhamnolipid biosurfactants, a temperature-sensitive heterologous production system under translation control of a fourU RNA thermometer from Salmonella was established to allow separating phases of preferred growth from product formation. Rhamnolipids as bulk chemicals represent a model system for future processes of industrial biotechnology and are therefore tied to the efficiency requirements in competition with the chemical industry. Experimental data confirms function of the RNA thermometer and suggests a major effect of temperature on specific rhamnolipid production rates with an increase of the average production rate by a factor of 11 between 25 and 38 °C, while the major part of this increase is attributable to the regulatory effect of the RNA thermometer rather than an unspecific overall increase in bacterial metabolism. The production capacity of the developed temperature sensitive-system was evaluated in a simple batch process driven by a temperature switch. Product formation was evaluated by efficiency parameters and yields, confirming increased product formation rates and product-per-biomass yields compared to a high titer heterologous rhamnolipid production process from literature.


Assuntos
Glicolipídeos/metabolismo , RNA Bacteriano/metabolismo , Salmonella/crescimento & desenvolvimento , Biotecnologia , Engenharia Metabólica , Modelos Moleculares , Conformação Molecular , RNA Bacteriano/química , Salmonella/genética , Salmonella/metabolismo , Temperatura , Termômetros
20.
Gastroenterology ; 136(3): 842-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19135997

RESUMO

BACKGROUND & AIMS: A fast-track program is a multimodal approach for patients undergoing colonic surgery that combines stringent regimens of perioperative care (fluid restriction, optimized analgesia, forced mobilization, and early oral feeding) to reduce perioperative morbidity, hospital stay, and cost. We investigated the impact of a fast-track protocol on postoperative morbidity in patients after open colonic surgery. METHODS: A randomized trial of patients in 4 teaching hospitals in Switzerland included 156 patients undergoing elective open colonic surgery who were assigned to either a fast-track program or standard care. The primary end point was the 30-day complication rate. Secondary end points were severity of complications, hospital stay, and compliance with the fast-track protocol. RESULTS: The fast-track protocol significantly decreased the number of complications (16 of 76 in the fast-track group vs 37 of 75 in the standard care group; P = .0014), resulting in shorter hospital stays (median, 5 days; range, 2-30 vs 9 days, respectively; range, 6-30; P < .0001). There was a trend toward less severe complications in the fast-track group. A multiple logistic regression analysis revealed fluid administration greater than the restriction limits (odds ratio, 4.198; 95% confidence interval, 1.7-10.366; P = .002) and a nonfunctioning epidural analgesia (odds ratio, 3.365; 95% confidence interval, 1.367-8.283; P = .008) as independent predictors of postoperative complications. CONCLUSIONS: The fast-track program reduces the rate of postoperative complications and length of hospital stay and should be considered as standard care. Fluid restriction and an effective epidural analgesia are the key factors that determine outcome of the fast-track program.


Assuntos
Doenças do Colo/cirurgia , Tempo de Internação , Equipe de Assistência ao Paciente , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgesia Epidural , Ingestão de Alimentos , Feminino , Hidratação , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Valor Preditivo dos Testes , Resultado do Tratamento
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