Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
1.
Facts Views Vis Obgyn ; 16(1): 87-91, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38551479

RESUMO

Background: Robotic-assisted hysterectomy (RAH) is a widely accepted minimally invasive approach for uterus removal. However, as RAH is typically performed in the umbilical region, it usually results in scars in cosmetically suboptimal locations. This is the first case of RAH with cervicosacropexy performed below the bikini line, using the new Dexter robotic system™. Objectives: The aim of this article is to show the surgical steps of the first RAH with cervicosacropexy performed below the bikini line with the new Dexter robotic system™ (Distalmotion), and furthermore assess the feasibility of this approach using this robotic platform. Materials and Methods: A 43-year-old woman with uterine adenomyosis and recurrent uterine prolapse underwent a robotic-assisted subtotal hysterectomy with cervicosacropexy, performed below the bikini line, using the Dexter robotic system™, at the Clinic of Gynecology and Obstetrics at Universitätsklinikum Schleswig-Holstein (UKHS) in Kiel, Germany. Main outcome measures: Perioperative data, surgical approach specifics, objective, and subjective outcomes of this new approach. Results: The procedure was performed without intra-operative complications; estimated blood loss was 10 ml. Operative time was 150 minutes, console time 120 minutes, total docking time 6 minutes. Dexter performed as expected; no device-related issues or robotic arm collisions occurred. The patient did not require pain medication and was released on the second postoperative day. Conclusion: RAH performed below the bikini line using the Dexter robotic system™ is a feasible, safe, and adequate procedure. These initial results should be confirmed and further extensively refurbished with larger patient cohorts, and functional and psychological outcomes need further investigation.

2.
Clin Oncol (R Coll Radiol) ; 35(5): e312-e318, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36804153

RESUMO

AIMS: Intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC) differ in prognosis and treatment. We aimed to non-invasively differentiate iCCA and HCC by means of radiomics extracted from contrast-enhanced standard-of-care computed tomography (CT). MATERIALS AND METHODS: In total, 94 patients (male, n = 68, mean age 63.3 ± 12.4 years) with histologically confirmed iCCA (n = 47) or HCC (n = 47) who underwent contrast-enhanced abdominal CT between August 2014 and November 2021 were retrospectively included. The enhancing tumour border was manually segmented in a clinically feasible way by defining three three-dimensional volumes of interest per tumour. Radiomics features were extracted. Intraclass correlation analysis and Pearson metrics were used to stratify robust and non-redundant features with further feature reduction by LASSO (least absolute shrinkage and selection operator). Independent training and testing datasets were used to build four different machine learning models. Performance metrics and feature importance values were computed to increase the models' interpretability. RESULTS: The patient population was split into 65 patients for training (iCCA, n = 32) and 29 patients for testing (iCCA, n = 15). A final combined feature set of three radiomics features and the clinical features age and sex revealed a top test model performance of receiver operating characteristic (ROC) area under the curve (AUC) = 0.82 (95% confidence interval =0.66-0.98; train ROC AUC = 0.82) using a logistic regression classifier. The model was well calibrated, and the Youden J Index suggested an optimal cut-off of 0.501 to discriminate between iCCA and HCC with a sensitivity of 0.733 and a specificity of 0.857. CONCLUSIONS: Radiomics-based imaging biomarkers can potentially help to non-invasively discriminate between iCCA and HCC.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Colangiocarcinoma/diagnóstico por imagem , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/patologia
3.
Biosens Bioelectron ; 216: 114642, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055131

RESUMO

In this study, we compare the electrical and optical signal transduction of nanoscale biosensors based on single-walled carbon nanotubes (SWCNTs). Solution processable single-stranded (ss) DNA-wrapped SWCNTs were used for the fabrication of the distinct sensors. For electrical measurements, SWCNTs were assembled from solution onto pre-patterned electrodes by electric-field-assisted assembly in field-effect transistor (FET) configuration. A combination of micro- and nano-fabrication and microfluidics enabled the integration into a sensing platform that allowed real-time and reversible detection. For optical measurements, the near-infrared (NIR) fluorescence of the SWCNTs was acquired directly from solution. The detection of important biomolecules was investigated in high-ionic strength solution (0.5xPBS). Increase in fluorescence intensities correlated with a decrease in the SWCNTs electrical current and enabled detection of the important biomolecules dopamine, epinephrine, and ascorbic acid. For riboflavin, however, a decrease in the fluorescence intensity could not be associated with changes in the SWCNTs electrical current, which indicates a different sensing mechanism. The combination of SWCNT-based electrical and optical transduction holds great potential for selective detection of biomarkers in next generation portable diagnostic assays.


Assuntos
Técnicas Biossensoriais , Nanotubos de Carbono , Ácido Ascórbico , DNA , DNA de Cadeia Simples , Dopamina , Epinefrina , Neurotransmissores , Riboflavina
5.
BMC Musculoskelet Disord ; 21(1): 759, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208124

RESUMO

BACKGROUND: Legg-Calvé-Perthes (LCP) is a common orthopedic childhood disease that causes a deformity of the femoral head and to an adaptive deformity of the acetabulum. The altered joint biomechanics can result in early joint degeneration that requires total hip arthroplasty. In 2002, Ganz et al. introduced the femoral head reduction osteotomy (FHRO) as a direct joint-preserving treatment. The procedure remains one of the most challenging in hip surgery. Computer-based 3D preoperative planning and patient-specific navigation instruments have been successfully used to reduce technical complexity in other anatomies. The purpose of this study was to report the first results in the treatment of 6 patients to investigate whether our approach is feasible and safe. METHODS: In this retrospective pilot study, 6 LCP patients were treated with FHRO in multiple centers between May 2017 and June 2019. Based on patient-specific 3D-models of the hips, the surgeries were simulated in a step-wise fashion. Patient-specific instruments tailored for FHRO were designed, 3D-printed and used in the surgeries for navigating the osteotomies. The results were assessed radiographically [diameter index, sphericity index, Stulberg classification, extrusion index, LCE-, Tönnis-, CCD-angle and Shenton line] and the time and costs were recorded. Radiologic values were tested for normal distribution using the Shapiro-Wilk test and for significance using Wilcoxon signed-rank test. RESULTS: The sphericity index improved postoperatively by 20% (p = 0.028). The postoperative diameter of the femoral head differed by only 1.8% (p = 0.043) from the contralateral side and Stulberg grading improved from poor coxarthrosis outcome to good outcome (p = 0.026). All patients underwent acetabular reorientation by periacetabular osteotomy. The average time (in minutes) for preliminary analysis, computer simulation and patient-specific instrument design was 63 (±48), 156 (±64) and 105 (±68.5), respectively. CONCLUSION: The clinical feasibility of our approach to FHRO has been demonstrated. The results showed significant improvement compared to the preoperative situation. All operations were performed by experienced surgeons; nevertheless, three complications occurred, showing that FHRO remains one of the most complex hip surgeries even with computer assistance. However, none of the complications were directly related to the simulation or the navigation technique.


Assuntos
Cabeça do Fêmur , Doença de Legg-Calve-Perthes , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Criança , Simulação por Computador , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/cirurgia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Doença de Legg-Calve-Perthes/cirurgia , Osteotomia , Projetos Piloto , Radiografia , Estudos Retrospectivos , Resultado do Tratamento
6.
Phys Chem Chem Phys ; 19(48): 32433-32442, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29186223

RESUMO

The dication Ne and its stability properties are studied by ab initio methods. Assuming the Born-Oppenheimer approximation and employing multireference configuration interaction techniques, potential energy curves of its low-lying electronic spectrum have been computed and analyzed. In addition to identifying metastable electronic and vibrational states, possible electronic transitions and decay mechanisms are examined. Our results also shed new light on the role of the dication as an excimer system and the interpretation of experimentally observed continua in Ne2 ultraviolet emission spectra.

7.
Chem Commun (Camb) ; 52(67): 10285-8, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27470912

RESUMO

Reactions between [Tc(I)(NO)X2(PPh3)2(CH3CN)] complexes (X = Cl, Br) and KCp form the pseudotetrahedral organotechnetium compounds [Tc(I)(NO)(Cp)(PPh3)X]. The halide ligands can readily be replaced by other halides or organometallic ligands giving access to a novel family of technetium(i) compounds with the robust {Tc(NO)(Cp)(PPh3)}(+) core.

8.
J Theor Biol ; 315: 71-80, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-22982289

RESUMO

The rapidly increasing amount of experimental biological data enables the development of large and complex, often genome-scale models of molecular systems. The simulation and analysis of these computer models of metabolism, signal transduction, and gene regulation are standard applications in systems biology, but size and complexity of the networks limit the feasibility of many methods. Reduction of networks provides a hierarchical view of complex networks and gives insight knowledge into their coarse-grained structural properties. Although network reduction has been extensively studied in computer science, adaptation and exploration of these concepts are still lacking for the analysis of biochemical reaction systems. Using the Petri net formalism, we describe two local network structures, common transition pairs and minimal transition invariants. We apply these two structural elements for network reduction. The reduction preserves the CTI-property (covered by transition invariants), which is an important feature for completeness of biological models. We demonstrate this concept for a selection of metabolic networks including a benchmark network of Saccharomyces cerevisiae whose straightforward treatment is not yet feasible even on modern supercomputers.


Assuntos
Redes e Vias Metabólicas , Saccharomyces cerevisiae/metabolismo , Biologia de Sistemas/métodos , Algoritmos
9.
Eur J Clin Invest ; 38(1): 53-60, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18173551

RESUMO

BACKGROUND: Presenting the same histological diagnosis, multiple myeloma (MM) shows a large genomic variety, resulting in variable times of overall survival. MATERIALS AND METHODS: To investigate major cytogenetic categories (any 14q-translocation, t(11;14), t(4;14), 13q-deletions, 17p-deletions) and their clinical consequences in MM after a pre-existing monoclonal gammopathy (MM post-MGUS), we performed a comparative analysis of 41 patients with MM post-MGUS and 287 patients with unknown prior history MM (U-MM). RESULTS: In MM post-MGUS, a t(11;14) was found to be more frequent than in U-MM (24% vs. 14%) and it was associated with significantly shortened survival (24 months vs. 70 months in U-MM; P = 0.01). MM post-MGUS was further characterized by a higher frequency of 13q-deletions only (absence of all other specific abnormalities; 28% vs. 12% in U-MM; P = 0.02). A 13q-deletion only was an indicator of long survival in MM post-MGUS (median not yet reached) as opposed to U-MM (median survival, 29 months; P = 0.001). 17p-deletions were infrequent in MM post-MGUS (3% vs. 16% in U-MM; P = 0.04). Survival times for patients with t(4;14) and/or 17p-deletions and other abnormalities were similar in both MM patient cohorts. CONCLUSIONS: Our data suggest that t(11;14) and 13q-deletions have distinct prognostic implications in the context of MM post-MGUS.


Assuntos
Deleção Cromossômica , Gamopatia Monoclonal de Significância Indeterminada/complicações , Mieloma Múltiplo/genética , Translocação Genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Prognóstico , Taxa de Sobrevida
10.
Eur J Haematol ; 78(3): 227-34, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17253972

RESUMO

Little is known about tumor-related prognostic factors, in particular specific chromosomal abnormalities, in young patients with multiple myeloma (MM). We therefore investigated the chromosomal pattern by interphase fluorescence in situ hybridization (chromosomes 13q14, 14q32-translocations, chromosomes associated with hyperdiploidy) in 38 young patients with MM (age <45 yr) and compared the results with those observed in 69 patients with intermediate age (45-70 yr) and 64 elderly patients (age >70 yr). All chromosomal patterns were not significantly different between the three age cohorts. Similarly, standard MM parameters were equally distributed between these MM patient populations. However, survival by the International Staging System (ISS) for MM revealed marked differences between stage I/II (median survival not yet reached) and stage III (23.4 months; P < 0.0003) among young MM patients. A significant survival difference between ISS-stage I/II and ISS-stage III patients was also noted in the intermediate age group (median 65.4 months vs. 24.6 months; P = 0.0009). However, this difference disappeared among elderly MM patients (39.6 months in ISS-stage I/II vs. 32 months in ISS-stage III patients; P = 0.94), but it was unrelated to the cytogenetic pattern. Our results indicate that MM in young patients does not represent a distinct biologic entity, and that short survival of younger MM patients at ISS-stage III is independent of the molecular cytogenetic pattern.


Assuntos
Aberrações Cromossômicas , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Humanos , Hibridização in Situ Fluorescente , Internacionalidade , Interfase , Pessoa de Meia-Idade , Estadiamento de Neoplasias/normas , Prognóstico , Taxa de Sobrevida
11.
Leukemia ; 21(1): 164-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17096015

RESUMO

Studies of bortezomib in patients with relapsed multiple myeloma (MM) suggested that bortezomib may be active even in the presence of adverse prognostic factors. We therefore evaluated 62 patients with relapsed/refractory MM who were treated with single-agent bortezomib, and addressed the question whether or not the negative prognostic impact of unfavorable cytogenetic abnormalities may be overcome by bortezomib. By interphase fluorescence in situ hybridization (FISH), a deletion of chromosome 13q14 [del(13q14)] was present in 33 patients (53%). Overall response rates to bortezomib were similar in patients with and without del(13q14) (45 versus 55%; P=0.66), and rates of complete remission (CR) near CR were also not different between the two patient populations (18 versus 14%). Three patients had a t(4;14)(p16;q32) in addition to del(13q14), and all of them had a >50% paraprotein reduction. Median duration of response was 12.3 months in patients with del(13q14) compared with 9.3 months in patients with normal 13q-status (P=0.25), and survival was also not different between the two patient populations. Patients not benefiting from single-agent bortezomib were characterized by the combined presence of a del(13q14) and low serum albumin (median survival 4.6 months). Our results provide evidence for remarkable activity of bortezomib in MM with del(13q14). Patients who do not respond to bortezomib and consecutively have short time to treatment failure and overall survival can be identified by low serum albumin in addition to del(13q14) and should be considered for bortezomib combinations.


Assuntos
Antineoplásicos/uso terapêutico , Ácidos Borônicos/uso terapêutico , Deleção Cromossômica , Cromossomos Humanos Par 13 , Mieloma Múltiplo/tratamento farmacológico , Pirazinas/uso terapêutico , Adulto , Idoso , Bortezomib , Estudos de Coortes , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico , Recidiva , Análise de Sobrevida
12.
Dermatology ; 211(2): 84-92, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16088151

RESUMO

BACKGROUND: The c-myb oncogene is a transcription factor that regulates proliferation, differentiation and apoptosis of haematopoietic cells and activated T cells by binding to promoter sequences of such genes as c-myc or bcl-2 that are expressed in cutaneous T-cell lymphoma (CTCL). OBJECTIVE: Our study was performed in order to evaluate c-myb expression as a quantitative parameter for differential diagnosis in leukaemic and non-leukaemic variants of CTCL. METHODS: c-myb expression was analysed in lesional skin and in the peripheral blood of 21 patients with mycosis fungoides (MF), 15 patients with Sézary syndrome (SS) and 15 patients with inflammatory skin diseases using immunohistochemistry and semiquantitative as well as quantitative RT-PCR. RESULTS: Immunohistochemistry confirmed expression of c-myb in the lesional skin of the majority of CTCL patients with a tendency towards higher expression in SS (1.86 +/- 0.5) versus MF (1.2 +/- 0.7) while c-myb was absent from the lesional skin of patients with inflammatory skin diseases. c-myb was overexpressed in the peripheral blood in all SS patients (100% SS vs. 35.7% MF) at a high expression level (51,335.31 +/- 31,960.32 AU in SS vs. 1,226.35 +/- 1,258.29 AU in MF using semiquantitative RT-PCR, and 5.72 x 10(-2) +/- 2.27 x 10(-2) in SS vs. 0.91 x 10(-2) +/- 1.18 x 10(-2) in MF vs. 0.24 x 10(-2) +/- 0.11 x 10(-2) in inflammatory skin disease using quantitative RT-PCR). CD4+ cells from the peripheral blood of SS patients and cell lines in vitro showed the highest c-myb expression levels upon quantitative RT-PCR (23.27 x 10(-2) and 10.78 x 10(-2) +/- 7.24 x 10(-2)). CONCLUSION: Overexpression of c-myb in skin lesions of both non-leukaemic and leukaemic CTCL independent of the stage of the disease indicates that it acts early in disease development. Nevertheless, if positive, c-myb expression in lesional skin is a clear-cut diagnostic marker for CTCL as compared to inflammatory skin diseases. High-level expression of c-myb in the peripheral blood as assessed by quantitative RT-PCR constitutes an additional diagnostic parameter for SS and may be especially useful in cases in which morphological determination of Sézary cells or FACS analysis of CD7 and CD26 remain inconclusive.


Assuntos
Biomarcadores Tumorais/sangue , Genes myb/genética , Linfoma Cutâneo de Células T/genética , Neoplasias Cutâneas/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Southern Blotting , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Linfoma Cutâneo de Células T/sangue , Linfoma Cutâneo de Células T/patologia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/sangue , Micose Fungoide/genética , Micose Fungoide/patologia , Estadiamento de Neoplasias , Prognóstico , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Sensibilidade e Especificidade , Fatores Sexuais , Síndrome de Sézary/genética , Síndrome de Sézary/mortalidade , Síndrome de Sézary/patologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia
13.
Leukemia ; 18(11): 1879-82, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15385925

RESUMO

Molecular and genetic events associated with the transition from monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM) are still poorly characterized. We investigated serial bone marrow specimens from 11 patients with MGUS who eventually progressed to MM (MM post-MGUS) by interphase fluorescence in situ hybridization for immunoglobulin heavy-chain gene (IgH) translocations and chromosome 13q deletions (del(13q)). In nine patients, IgH translocations were present both in MGUS and MM post-MGUS plasma cells, including three t(11;14)(q13;q32) and one t(4;14)(p16;q32), which was observed already 92 months prior to MM. Similarly, all five MM patients with del(13q) had this aberration already at the MGUS stage. Two patients without IgH translocation and del(13q) had chromosomal gains suggesting hyperdiploidy, but IgH translocations and/or del(13q) did not emerge at MM post-MGUS. IgH translocations and del(13q) are early genetic events in monoclonal gammopathies, suggesting that additional events are required for the transition from stable MGUS to progressive MM.


Assuntos
Cromossomos Humanos Par 13 , Deleção de Genes , Cadeias Pesadas de Imunoglobulinas/genética , Mieloma Múltiplo/genética , Paraproteinemias/genética , Translocação Genética , Idoso , Medula Óssea , Progressão da Doença , Humanos , Hibridização in Situ Fluorescente , Interfase , Pessoa de Meia-Idade
14.
Leukemia ; 18(1): 146-55, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14603341

RESUMO

To define reproducible criteria for subgroups of diffuse large B-cell lymphomas (DLBCL), including lymphomas with plasmablastic/plasmacytoid features (PB/PC-Fs), we investigated 66 DLBCL; the samples were categorized as either centroblastic (CB), immunoblastic (IB) or PB/PC-F applying standardized morphologic criteria. Blinded specimens were reviewed by three independent pathologists. The final consensus classification included 44 CB (67%), seven IB (10%) and 15 PB/PC-F (23%). The interobserver agreement between two centers (Vienna, Würzburg) was 93.5%. Most PB/PC-F were CD20+, cIgM+, MUM-1+, CD138+/-, bcl-6-, corresponding to an activated B-cell phenotype. Immunoglobulin-V(H) gene mutation analysis was consistent with a germinal or postgerminal center-cell origin. By fluorescence in situ hybridization analysis, 11/13 (85%) PB/PC-F had a monoallelic TP53 deletion. The pretreatment characteristics of patients with PB/PC-F included a tendency for more B symptoms, extranodal disease and a higher IPI. Importantly, PB/PC-F were resistant to standard chemotherapy (complete remission rate 47%, relapse rate 71%) and even autologous stem-cell transplantation. The median overall survival (OS) (14 months, P<0.002) and disease-free survival (6 months, P=0.02) were significantly shorter compared to patients with CB and IB. The OS difference was pronounced within the low and low-intermediate IPI risk group (P<0.001). Our data indicate a strong association of plasmablastic/plasmacytoid morphology with TP53 deletions, poor response to chemotherapy and short survival.


Assuntos
Genes p53/genética , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/patologia , Plasmócitos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores/análise , Feminino , Seguimentos , Genes de Imunoglobulinas , Centro Germinativo/imunologia , Herpesvirus Humano 4/genética , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Linfoma de Células B/classificação , Linfoma de Células B/mortalidade , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Imunoblástico de Células Grandes/classificação , Linfoma Imunoblástico de Células Grandes/mortalidade , Linfoma Imunoblástico de Células Grandes/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Viral/genética , Deleção de Sequência , Taxa de Sobrevida , Resultado do Tratamento
15.
Ann Oncol ; 14(11): 1667-72, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14581276

RESUMO

It has been established that high-dose chemotherapy (HDT) improves the therapeutic outcome of patients with multiple myeloma (MM) as compared with standard-dose therapy (SDT); however, little is known about the impact of HDT on different prognostic groups of MM patients. We therefore compared the survival times of 77 patients with previously untreated MM who were enrolled in HDT regimens with those of 64 similar patients <65 years old, who would be eligible for HDT but were treated by SDT. Overall, HDT was superior to SDT with respect to achievement of complete remissions (28% versus 2%; P <0.0001) and improvement of progression-free survival (PFS) (30.2 versus 21.2 months; P = 0.01) as well as overall survival (OS) (median 54.9 versus 49.4 months; P = 0.048). According to the chromosome 13q14 status as determined by fluorescence in situ hybridization and serum levels of beta(2)-microglobulin (beta(2)M), MM patients were separated into a standard-risk group (normal chromosome 13q14 and beta(2)M 4 mg/l). Among patients of the high-risk group, both PFS (26.4 versus 10.7 months; P = 0.004) and OS times (40 versus 23 months; P = 0.05) were longer in patients receiving HDT compared with patients treated by SDT. In the standard-risk group, PFS and OS times were not significantly different between HDT patients and SDT patients. Results of this retrospective analysis suggest that the beneficial effects of HDT are greater in MM patients with high-risk features than in patients with absence of such poor prognostic indicators.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cromossomos Humanos Par 13 , Mieloma Múltiplo/tratamento farmacológico , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/genética , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento , Microglobulina beta-2/sangue
16.
J Theor Biol ; 224(4): 539-49, 2003 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-12957125

RESUMO

Previously, numerical simulations have shown that evolving systems can be stabilized against emerging parasites by pattern formation in spatially extended flow reactors. Hence, it can be argued that pattern formation is a prerequisite for any experimental investigation of the biochemical evolution of cooperative function. Here, we study a model of an experimental biochemical system for the cooperative in vitro amplification of DNA strands and show that emerging parasites can induce a complex pattern formation even when no pattern formation occurs without parasites. In an adiabatic approximation where the cooperative amplification reaction is assumed to adapt fast to slowly emerging parasites, the parasite concentration itself acts as a Steuer parameter for the selection of various complex patterns. Without such an adiabatic approximation only transient patterns emerge. As any species can grow for very low concentrations, the parasite is able to infect the entire reactor and the system is finally diluted out. In the experimental biochemical system, however, the species are individual molecules and the growth of spatially separated, non-infected regions becomes feasible. Hence a cutoff threshold for the minimal concentration is applied. In these simulations the otherwise lethal infection by parasites induces the formation of spatiotemporal spirals, and this spatial structure help the host and parasitoid species to survive together. These theoretical results describe an inherent property of cooperative reactions and have an important impact on experimental investigations on the molecular evolution and complex function in spatially extended reactors. Since the formation of the complex pattern is restricted either to a rather large cutoff value or a special choice of the kinetic parameters, we, however, conclude that the persistence of evolving cooperative amplification is not possible in a simple reaction-diffusion reactor. Experimental set-ups with patchy environments, e.g. biomolecular amplification in coupled microstructured flow chambers or in microemulsion, are eligible candidates for the observation of such a self-organized pattern selection.


Assuntos
Evolução Molecular , Interações Hospedeiro-Parasita , Parasitos/crescimento & desenvolvimento , Seleção Genética , Animais , RNA Polimerases Dirigidas por DNA/genética , Modelos Genéticos , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico/métodos
18.
Swiss Surg ; 9(6): 283-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14725097

RESUMO

AIM OF STUDY: To investigate the short- and long-term outcome of patients with isolated lateral malleolar fracture type B treated with a single hemicerclage out of metallic wire or PDS cord. METHODS: Over an 8-year period 97 patients were treated with a single hemicerclage for lateral malleolar fracture type B and 89 were amenable to a follow-up after mean 39 months, including interview, clinical examination and X-ray controls. RESULTS: The median operation time was 35 minutes (range 15-85 min). X-ray controls within the first two postoperative days revealed an anatomical restoration of the upper ankle joint in all but one patient. The complication rate was 8%: hematoma (2 patients), wound infection (2), Sudeck's dystrophy (2) and deep vein thrombosis (1). Full weight-bearing was tolerated at median 6.0 weeks (range 2-26 weeks). No secondary displacement, delayed union or consecutive arthrosis of the upper ankle joint was observed. All but one patient had restored symmetric joint mobility. Ninety-seven percent of patients were satisfied or very satisfied with the outcome. Following bone healing, hemicerclage removal was necessary in 19% of osteosyntheses with metallic wire and in none with PDS cord. CONCLUSION: The single hemicerclage is a novel, simple and reliable osteosynthesis technique for isolated lateral type B malleolar fractures and may be considered as an alternative to the osteosynthesis procedures currently in use.


Assuntos
Traumatismos do Tornozelo/cirurgia , Fios Ortopédicos , Fixação Interna de Fraturas/métodos , Polidioxanona , Suturas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Traumatismos do Tornozelo/diagnóstico por imagem , Feminino , Seguimentos , Consolidação da Fratura/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia
19.
Leuk Lymphoma ; 44(11): 1943-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14738147

RESUMO

Remarkable results of the treatment of refractory multiple myeloma with thalidomide have been reported. In most preceding studies, the given thalidomide dose was escalated to a maximum tolerated dose of up to 800 mg/d. The frequency of adverse effects correlates with dose intensity. Since a significant gain of therapeutic effects could not be observed as thalidomide dosage was escalated, the optimal dose of thalidomide remains to be determined. We report the results of a study with low dose thalidomide (median administered dose 100 mg/d, range 50-400 mg/d). Twenty-four relapsed (n = 19) or resistant (n = 5) multiple myeloma patients were included in the study. Twelve patients (50%) received thalidomide as monotherapy, 8 patients (33%) received a combination of thalidomide and dexamethasone (every 4 weeks 40 mg/day for 4 days) and 4 patients (17%) who were resistant to vincristine, doxorubicin, dexamethasone (VAD) received VAD combined with thalidomide. Overall, a response was observed in 12 patients (50%). Of the 12 patients treated with low dose thalidomide alone 5 (42%) responded, of the 8 patients who received a combination of thalidomide and dexamethasone 5 (63%) responded and of the 4 patients who had thalidomide in addition to VAD 2 patients (50%) responded. In 3 patients, thalidomide treatment had to be discontinued because of side effects and 1 patient died before response could be assessed. We conclude that low dose thalidomide is an effective and safe rescue therapy in relapsing or refractory multiple myeloma. Response to thalidomide might be dependent on prognostic parameters and tumor burden. To answer these questions larger prospective studies are necessary.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Talidomida/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Terapia de Salvação , Resultado do Tratamento , Vincristina/administração & dosagem
20.
Ann Hematol ; 80(8): 445-51, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11563588

RESUMO

During the past decade, new developments have increased our understanding of the biological features of multiple myeloma (MM), and novel therapeutic approaches have improved the outcome and quality of life. The importance of both the malignant clone and the bone marrow environment for disease evolution and propagation has been recognized, and therapeutic approaches that target both components of the disease process appear to be most promising. Along this line, thalidomide has been observed to exert activity in chemotherapy-refractory MM and thus expands the therapeutic armamentarium against MM. Use of high-dose melphalan with autologous stem cell transplantation has resulted in an improved rate of complete remissions as well as prolonged event-free and overall survival. Novel treatment strategies exploiting anti-myeloma immunity (nonmyeloablative allogeneic transplantation, vaccination) are being investigated and carry the potential to further improve the outcome of patients with MM.


Assuntos
Mieloma Múltiplo/fisiopatologia , Mieloma Múltiplo/terapia , Humanos , Mieloma Múltiplo/genética , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...