Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
1.
J Thromb Thrombolysis ; 52(3): 848-853, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33649980

RESUMO

Multiple myeloma (MM) is associated to an increased incidence of venous thromboembolism (VTE). IMPEDE-VTE score constitutes a valuable risk assessment tool for VTE prediction in first-line MM patients. Nevertheless, refinement of the primary thromboprophylaxis category of this score (which pools aspirin and heparin) seems desirable. To investigate the role of the type of thromboprophylaxis, within IMPEDE-VTE score, for VTE prediction in MM patients. Retrospective analysis of a single-center cohort of 438 MM patients receiving first-line antimyeloma treatment (1991-2020). IMPEDE-VTE score was calculated. Primary thromboprophylaxis was additionally stratified into aspirin- and heparin-based regimen subgroups. VTE risk was analyzed by Cox regression. Median follow-up during first-line antimyeloma treatment was 6.0 months (IQR 4.1-9.0 months). Twenty-three patients developed VTE (5.3%, 95%CI 3.4-7.8%). IMPEDE-VTE score showed a notable predictive value (area under the ROC curve: 0.70, 95%CI 0.60-0.80). Cox analysis confirmed that 1-point increase in the score resulted in a 1.3-fold increase in VTE risk (HR 1.30, 95%CI 1.13-1.53, p < 0.001). In the multivariable analysis, the type of primary thromboprophylaxis (heparin versus aspirin) was an independent predictive factor (HR 0.15, 95% CI 0.05-0.47, p = 0.001). The combined model showed a higher goodness-of-fit (Akaike Information Criterion [AIC]: 99) than IMPEDE-VTE separately (AIC:235). Our analysis contributes to the external validation of IMPEDE-VTE score for the prediction of VTE in MM. But more interestingly, our results demonstrate that among those patients receiving thromboprophylaxis, the type of regimen (heparin versus aspirin) adds independent predictive value and should be explored for a more accurate risk assessment.


Assuntos
Mieloma Múltiplo , Trombose Venosa , Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Heparina/efeitos adversos , Humanos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
2.
Int J Mol Sci ; 21(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991626

RESUMO

Immunotherapy has changed the oncology landscape during the last decade and become standard of care for several cancers. The combinations of immunotherapy with other treatment modalities are also being investigated. One of the challenges to investigate such combinations is to identify suitable mouse models for the pre-clinical experiments. In the past, we and other researchers showed that murine B16-F10 melanoma in C57Bl6 mice is refractory to treatment with immune checkpoint inhibitors. In this work we studied the suitability of an alternative syngeneic model, Cloudman S91 murine melanoma in DBA/2 mouse (DBA/2NCrl), to study the combination of immunotherapy targeting PD-1 and radioimmunotherapy targeting melanin. DBA/2 male and female mice were injected subcutaneously with 3-6 million Cloudman S91 cells. When the tumors reached ~150 mm3 volume, the animals were treated intraperitoneally with PBS (sham), h8C3 unlabeled (cold) antibody to melanin, immunotherapy with anti-PD-1 antibody, radioimmunotherapy with 213Bismuth (213Bi)-labeled h8C3 antibody, or several combinations of immunotherapy and radioimmunotherapy. Treatments with immunotherapy alone produced very modest effect on the tumor size, while combination therapy resulted in significant slowing down of the tumor growth, increased animal survival, and no decrease in animal body weight. We conclude that Cloudman S91 murine melanoma in DBA/2 mouse is a suitable model to evaluate combination of immunotherapy of melanoma with tangentially targeted treatments.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Bismuto/farmacologia , Melanoma Experimental/terapia , Radioimunoterapia , Radioisótopos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Receptor de Morte Celular Programada 1/imunologia
3.
Rev Epidemiol Sante Publique ; 66(2): 99-105, 2018 Mar.
Artigo em Francês | MEDLINE | ID: mdl-29530441

RESUMO

BACKGROUND: The Forensic medicine reform in 2011 enabled the development of forensic units specialized in multidisciplinary care of victims of criminal offences. Thanks to an annual budgetary allocation, the Ministry of Justice handles the financing of judicial acts, while the health care facilities assume the medical, psychological and social aspects. The objective of this study was to determine the direct costs of medical care provided to rape victims (such as defined in the article 222-23 of the Penal Code) in order to see how its funding could be reconsidered to prevent any additional cost that could be caused by non-sufficient medical, psychological and social care. Furthermore, this first assessment may serve as a basis for further reflection on creating other medical judicial units but also for reviewing existing structures. METHODS: The direct costs for medical care of a recent rape victim (<48hours) was quantified by including staff and consumables costs, treatments, biological tests and other expenses. RESULTS: The overall time for the entire medical care procedure was approximately three hours, for an overall cost of 673.92€, of which 41.5 % (279.90€) was paid by the Ministry of Justice. The medical, psychological and social aspects stood for the major expenditure items (394.02€), attributable mainly to the biological screening tests for sexually transmissible infections (STIs). CONCLUSION: These frequent situations require the convergence of human and material needs with a financial burden shared between the Ministry of Justice and health establishments. Authors suggest that in the annual hospital budgetary allocation allotted by the Ministry of Justice, the care of victims of sexual assault be based on the rate of day hospitalization "Medicine, medical specialties part time day or night common regime", allowing to provide optimal multidisciplinary care, which lessens the risks of complications and reduces the global cost created by these situations.


Assuntos
Vítimas de Crime , Serviço Hospitalar de Emergência , Custos de Cuidados de Saúde , Estupro , Vítimas de Crime/economia , Vítimas de Crime/psicologia , Vítimas de Crime/estatística & dados numéricos , Procedimentos Clínicos/economia , Procedimentos Clínicos/organização & administração , Procedimentos Clínicos/estatística & dados numéricos , Emergências/economia , Emergências/epidemiologia , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Medicina Legal/economia , Medicina Legal/estatística & dados numéricos , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Estupro/psicologia , Estupro/reabilitação , Estupro/estatística & dados numéricos , Estudos Retrospectivos , Delitos Sexuais/economia , Delitos Sexuais/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/economia , Infecções Sexualmente Transmissíveis/prevenção & controle
4.
Osteoporos Int ; 27(12): 3439-3447, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27368699

RESUMO

We analysed the impact of a standardized order set empowering staff nurses to independently manage a Fracture Liaison Service over a 9-month period. Nurses identified between 30 and 70 % of non-hip fragility fractures to the unit in charge of management over time. The latter managed 58 % of referred patients. INTRODUCTION: The main goal of this study was to evaluate the impact of a standardized order set empowering nurses to independently manage a fracture liaison service (FLS). METHODS: Since November 2014, an order set allowed nurses of a Montreal hospital, Quebec, Canada to entirely manage an FLS on their own. Nurses followed an 6-h training program on-site. Emergency department (ED) and orthopaedic outpatient clinic (OC) nurses identified non-hip fragility fractures. Medical day treatment unit (MDTU) nurses were in charge of the management (investigation and treatment initiation). The list of patients, 50 years and older, with a fracture were retrieved for the period of November 2014 to July 2015. Performance was assessed with the rate of identification over time and the rate of management of non-hip fragility fractures. RESULTS: Over the 9-month period, 346 patients of ≥50 years old were seen for a fracture, of which 190 met fragility criteria (excluding hip fractures). A sinusoid pattern of rates of identification between 30-70 % was observed over time. An average proportion of 58.1 % of fracture patients were managed by MDTU nurses. CONCLUSIONS: A standardized order set legally allowing nurses to manage an FLS led to identification rates varying from 30-70 % and a management rate close to 60 % for referred patients over a 9-month period, which largely exceeds that of standard care. Identification was mostly compromised by difficulty integrating the order set into routine practice. Enforcement of the hospital policy on fragility fractures could help yield efficiency of identification of osteoporosis-related fractures by the staff.


Assuntos
Fraturas por Osteoporose/enfermagem , Fraturas por Osteoporose/terapia , Avaliação de Processos em Cuidados de Saúde , Humanos , Recursos Humanos de Enfermagem Hospitalar , Osteoporose , Quebeque
5.
Diabetes Obes Metab ; 18(5): 519-27, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876427

RESUMO

AIMS: To examine whether co-administration of intestinal alkaline phosphatase (IAP) with antibiotics early in life may have a preventive role against metabolic syndrome (MetS) in mice. METHODS: A total of 50 mice were allocated to four treatment groups after weaning. Mice were treated with azithromycin (AZT) ± IAP, or with no AZT ± IAP, for three intermittent 7-day cycles. After the last treatment course, the mice were administered a regular chow diet for 5 weeks and subsequently a high-fat diet for 5 weeks. Body weight, food intake, water intake, serum lipids, glucose levels and liver lipids were compared. 16S rRNA gene pyrosequencing was used to determine the differences in microbiome composition. RESULTS: Exposure to AZT early in life rendered mice susceptible to MetS in adulthood. Co-administration of IAP with AZT completely prevented this susceptibility by decreasing total body weight, serum lipids, glucose levels and liver lipids to the levels of control mice. These effects of IAP probably occur as a result of changes in the composition of specific bacterial taxa at the genus and species levels (e.g. members of Anaeroplasma and Parabacteroides). CONCLUSIONS: Co-administration of IAP with AZT early in life prevents mice from susceptibility to the later development of MetS. This effect is associated with alterations in the composition of the gut microbiota. IAP may represent a novel treatment against MetS in humans.


Assuntos
Fosfatase Alcalina/uso terapêutico , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Suplementos Nutricionais , Disbiose/prevenção & controle , Mucosa Intestinal/enzimologia , Síndrome Metabólica/prevenção & controle , Acholeplasma/classificação , Acholeplasma/efeitos dos fármacos , Acholeplasma/crescimento & desenvolvimento , Acholeplasma/isolamento & purificação , Fosfatase Alcalina/efeitos adversos , Animais , Bacteroides/classificação , Bacteroides/efeitos dos fármacos , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Bovinos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Disbiose/induzido quimicamente , Disbiose/microbiologia , Disbiose/fisiopatologia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/etiologia , Síndrome Metabólica/microbiologia , Camundongos Endogâmicos C57BL , Tipagem Molecular , Obesidade/complicações , Obesidade/etiologia , Obesidade/microbiologia , Obesidade/prevenção & controle , Desmame , Aumento de Peso/efeitos dos fármacos
6.
Osteoarthritis Cartilage ; 23(3): 414-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25479166

RESUMO

OBJECTIVE: To quantify early osteoarthritic-like changes in the structure and volume of subchondral bone plate and trabecular bone and properties of articular cartilage in a rabbit model of osteoarthritis (OA) induced by anterior cruciate ligament transection (ACLT). METHODS: Left knee joints from eight skeletally mature New Zealand white rabbits underwent ACLT surgery, while the contralateral (CTRL) right knee joints were left unoperated. Femoral condyles were harvested 4 weeks after ACLT. Micro-computed tomography imaging was applied to evaluate the structural properties of subchondral bone plate and trabecular bone. Additionally, biomechanical properties, structure and composition of articular cartilage were assessed. RESULTS: As a result of ACLT, significant thinning of the subchondral bone plate (P < 0.05) was accompanied by significantly reduced trabecular bone volume fraction and trabecular thickness in the medial femoral condyle compartment (P < 0.05), while no changes were observed in the lateral compartment. In both lateral and medial femoral condyles, the equilibrium modulus and superficial zone proteoglycan (PG) content were significantly lower in ACLT than CTRL joint cartilage (P < 0.05). Significant alterations in the collagen orientation angle extended substantially deeper into cartilage from the ACLT joints in the lateral femoral condyle relative to the medial condyle compartment (P < 0.05). CONCLUSIONS: In this model of early OA, significant changes in volume and microstructure of subchondral bone plate and trabecular bone were detected only in the femoral medial condyle, while alterations in articular cartilage properties were more severe in the lateral compartment. The former finding may be associated with reduced joint loading in the medial compartment due to ACLT, while the latter finding reflects early osteoarthritic changes in the lateral compartment.


Assuntos
Lesões do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Fêmur/patologia , Traumatismos do Joelho/patologia , Osteoartrite do Joelho/patologia , Animais , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Fêmur/diagnóstico por imagem , Fêmur/metabolismo , Imageamento Tridimensional , Traumatismos do Joelho/diagnóstico por imagem , Traumatismos do Joelho/metabolismo , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/metabolismo , Proteoglicanas/metabolismo , Coelhos , Microtomografia por Raio-X
7.
Gut ; 59(11): 1476-84, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20947883

RESUMO

BACKGROUND AND AIMS: The intestinal microbiota plays a critical role in maintaining human health; however, the mechanisms governing the normal homeostatic number and composition of these microbes are largely unknown. Previously it was shown that intestinal alkaline phosphatase (IAP), a small intestinal brush border enzyme, functions as a gut mucosal defence factor limiting the translocation of gut bacteria to mesenteric lymph nodes. In this study the role of IAP in the preservation of the normal homeostasis of the gut microbiota was investigated. METHODS: Bacterial culture was performed in aerobic and anaerobic conditions to quantify the number of bacteria in the stools of wild-type (WT) and IAP knockout (IAP-KO) C57BL/6 mice. Terminal restriction fragment length polymorphism, phylogenetic analyses and quantitative real-time PCR of subphylum-specific bacterial 16S rRNA genes were used to determine the compositional profiles of microbiotas. Oral supplementation of calf IAP (cIAP) was used to determine its effects on the recovery of commensal gut microbiota after antibiotic treatment and also on the colonisation of pathogenic bacteria. RESULTS: IAP-KO mice had dramatically fewer and also different types of aerobic and anaerobic microbes in their stools compared with WT mice. Oral supplementation of IAP favoured the growth of commensal bacteria, enhanced restoration of gut microbiota lost due to antibiotic treatment and inhibited the growth of a pathogenic bacterium (Salmonella typhimurium). CONCLUSIONS: IAP is involved in the maintenance of normal gut microbial homeostasis and may have therapeutic potential against dysbiosis and pathogenic infections.


Assuntos
Fosfatase Alcalina/fisiologia , Intestino Delgado/enzimologia , Intestino Delgado/microbiologia , Metagenoma/fisiologia , Administração Oral , Fosfatase Alcalina/deficiência , Fosfatase Alcalina/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Bactérias Aeróbias Gram-Negativas/isolamento & purificação , Bactérias Anaeróbias Gram-Negativas/isolamento & purificação , Homeostase/fisiologia , Metagenoma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento
8.
PLoS One ; 16(9): e0257353, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506616

RESUMO

Chronic Lymphocytic Leukemia (CLL) is the most prevalent leukemia in Western countries and is notable for its variable clinical course. This variability is partly reflected by the mutational status of IGHV genes. Many CLL samples have been studied in recent years by next-generation sequencing. These studies have identified recurrent somatic mutations in NOTCH1, SF3B1, ATM, TP53, BIRC3 and others genes that play roles in cell cycle, DNA repair, RNA metabolism and splicing. In this study, we have taken a deep-targeted massive sequencing approach to analyze the impact of mutations in the most frequently mutated genes in patients with CLL enrolled in the REM (rituximab en mantenimiento) clinical trial. The mutational status of our patients with CLL, except for the TP53 gene, does not seem to affect the good results obtained with maintenance therapy with rituximab after front-line FCR treatment.


Assuntos
Ciclofosfamida/administração & dosagem , Regulação Leucêmica da Expressão Gênica , Imunoterapia/métodos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/terapia , Mutação , Rituximab/administração & dosagem , Vidarabina/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Análise Mutacional de DNA , Feminino , Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Splicing de RNA , Vidarabina/administração & dosagem
9.
Can Urol Assoc J ; 14(12): 423-430, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32569563

RESUMO

INTRODUCTION: There remains uncertainty regarding the differences in patient outcomes between monopolar transurethral resection of the prostate (MTURP) and bipolar TURP (BTURP) in the management of lower urinary tract symptoms (LUTS) secondary to benign prostatic obstruction (BPO). METHODS: A systematic literature search was carried out up to March 19, 2019. Methods in the Cochrane Handbook were followed. Certainty of evidence (CoE) was assessed using the GRADE approach. RESULTS: A total of 59 randomized controlled trials (RCTs) with 8924 participants were included. BTURP probably results in little to no difference in International Prostate Symptom Score (IPSS) at 12 months (mean difference -0.24, 95% confidence internal [CI] -0.39--0.09; participants=2531; RCTs=16; moderate CoE) or health-related quality of life (HRQOL) at 12 months (mean difference -0.12, 95% CI -0.25-0.02; participants=2004, RCTs=11; moderate CoE), compared to MTURP. BTURP probably reduces TUR syndrome (relative risk [RR] 0.17, 95% CI 0.09-0.30; participants= 6,745, RCTs=44; moderate CoE) and blood transfusions (RR 0.42, 95% CI 0.30-0.59; participants=5727, RCTs=38; moderate CoE), compared to MTURP. BTURP may carry similar risk of urinary incontinence at 12 months (RR 0.20, 95% CI 0.01-4.06; participants=751; RCTs=4; low CoE), re-TURP (RR 1.02, 95% CI 0.44-2.40; participants=652, RCTs=6, I2=0%; low CoE) and erectile dysfunction (International Index of Erectile Function [IIEF-5]) at 12 months (mean difference 0.88, 95% CI -0.56-2.32; RCTs=3; moderate CoE), compared to MTURP. CONCLUSIONS: BTURP and MTURP probably improve urological symptoms to a similar degree. BTURP probably reduces TUR syndrome and blood transfusion slightly postoperatively. The moderate certainty of evidence available for primary outcomes suggests no need for further RCTs comparing BTURP and MTURP.

10.
Sci Rep ; 8(1): 5466, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615812

RESUMO

Metastatic melanoma remains difficult to treat despite recent approvals of several new drugs. Recently we reported encouraging results of Phase I clinical trial of radiolabeled with 188Re murine monoclonal IgM 6D2 to melanin in patients with Stage III/IV melanoma. Subsequently we generated a novel murine IgG 8C3 to melanin. IgGs are more amenable to humanization and cGMP (current Good Manufacturing Practice) manufacturing than IgMs. We performed comparative structural analysis of melanin-binding IgM 6D2 and IgG 8C3. The therapeutic efficacy of 213Bi- and 188Re-labeled 8C3 and its comparison with anti-CTLA4 immunotherapy was performed in B16-F10 murine melanoma model. The primary structures of these antibodies revealed significant homology, with the CDRs containing a high percentage of positively charged amino acids. The 8C3 model has a negatively charged binding surface and significant number of aromatic residues in its H3 domain, suggesting that hydrophobic interactions contribute to the antibody-melanin interaction. Radiolabeled IgG 8C3 showed significant therapeutic efficacy in murine melanoma, safety towards healthy melanin-containing tissues and favorable comparison with the anti-CTLA4 antibody. We have demonstrated that antibody binding to melanin relies on both charge and hydrophobic interactions while the in vivo data supports further development of 8C3 IgG as radioimmunotherapy reagent for metastatic melanoma.


Assuntos
Anticorpos/química , Anticorpos/imunologia , Melaninas/imunologia , Melanoma/imunologia , Melanoma/terapia , Radioimunoterapia/métodos , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/terapia , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Melanoma/patologia , Camundongos , Neoplasias Cutâneas/patologia , Relação Estrutura-Atividade , Melanoma Maligno Cutâneo
11.
Int J Lab Hematol ; 40(5): 549-555, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29774987

RESUMO

INTRODUCTION: The Revised International Prognostic Scoring System (IPSS-R) for myelodysplastic syndromes (MDS) has established an intermediate category where a disease-modifying intervention is a matter of debate. Flow cytometry allows us to determine a fraction of immature myeloid cells in a semiautomated procedure. The aim of this study, mirroring IPSS-R study inclusion criteria, was to test whether bone marrow (BM) CD34+My percentage has independent prognostic value in the MDS setting. METHODS: BM CD34+My cells were quantified, at diagnosis, selecting CD34+/CD45+/CD11b±/CD13+. Patients were excluded when receiving treatment for altering the natural course of the disease and when IPSS-R could not be calculated due to the lack of metaphases. Finally, Cox analyses were performed, on a series of 260 patients, for overall survival (OS) and time to acute myeloid leukemia (AML) transformation. RESULTS: By analyzing ROC curves, the most accurate prognostic variable, regarding blasts by cytology and CD34+ by cytometry, was the percentage of blasts by microscopy. The percentage of CD34+My in BM showed an AUC of 0.767 and 0.576 for time to AML transformation and OS, respectively. When performing a multivariate regression including the IPSS-R and the percentage of BM CD34+My cells >1%, both factors predicted for a shorter time to AML transformation. In addition, CD34+My percentage successfully stratified the intermediate IPSS-R category into two prognostic groups with a relative risk of 5.73 (95% CI [1.2-27.8]; P = .03). CONCLUSION: We found that BM CD34+My percentage has an independent value concerning the IPSS-R, especially relevant for the prediction of transformation to AML and within the intermediate group.

12.
Biosystems ; 87(2-3): 136-41, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17070987

RESUMO

In this article, we present a game theory based framework, named games network, for modeling biological interactions. After introducing the theory, we more precisely describe the methodology to model biological interactions. Then we apply it to the plasminogen activator system (PAs) which is a signal transduction pathway involved in cancer cell migration. The games network theory extends game theory by including the locality of interactions. Each game in a games network represents local interactions between biological agents. The PAs system is implicated in cytoskeleton modifications via regulation of actin and microtubules, which in turn favors cell migration. The games network model has enabled us a better understanding of the regulation involved in the PAs system.


Assuntos
Teoria dos Jogos , Ativadores de Plasminogênio/fisiologia , Movimento Celular/fisiologia , Modelos Biológicos , Neoplasias/patologia , Neoplasias/fisiopatologia , Transdução de Sinais/fisiologia , Biologia de Sistemas
13.
Orthop Traumatol Surg Res ; 103(2): 307-314, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28065868

RESUMO

BACKGROUND: The clinical significance of a positive culture to Propionibacterium acnes in orthopedic specimens remains unclear, whether about its role as a contaminant or a pathogen, or its impact as a coinfectant. Therefore, we performed a retrospective study to provide a more accurate description of the clinical impact of P. acnes in an orthopedic population aiming to determine: 1) if there is a clinical difference between P. acnes infection and contamination? 2) If there is a clinical difference between P. acnes monoinfection, and coinfection. HYPOTHESIS: There is a clinical difference between P. acnes infection and contamination. MATERIALS AND METHODS: Patients were selected over a five-year period, and those with a minimum of one positive culture for P. acnes, from any intraoperative orthopedic tissue sample, were included in the study. P. acnes infection was defined as the isolation of P. acnes from≥2 specimens, or in only one specimen, in the presence of typical perioperative findings and/or local signs of infection. RESULTS: A total of 68 patients had a positive P. acnes culture, 35 of which were considered to be infected. The infections affected mostly males (29/35-83%), occurred mostly in shoulders (22/35-63%), and at a site already containing an orthopedic implant (32/35-91%). Local inflammatory signs were present in half of the cases when an infection was diagnosed. Coinfection with other pathogens was present in 31% of patients (11/35). When comparing patients coinfected with P. acnes, and those who were monoinfected, the latter presented less often with local inflammatory signs. Recurrence rate was 24% (8/35) and the only risk factor for recurrence was the presence of a monoinfection. DISCUSSION: This study confirms the pathogenicity of P. acnes in an orthopedic population, as it is present in multiple samples in the same patient, and because it is present in cultures from cases with clinical recurrence. Our study showed that monoinfections differ from coinfections mainly by their higher risk of recurrence. LEVEL OF EVIDENCE: Level IV retrospective case series.


Assuntos
Infecções por Bactérias Gram-Positivas/microbiologia , Prótese Articular/microbiologia , Procedimentos Ortopédicos , Propionibacterium acnes/isolamento & purificação , Idoso , Coinfecção/diagnóstico , Coinfecção/microbiologia , Feminino , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Articulação do Ombro/microbiologia
14.
J Biomech ; 65: 96-105, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29108850

RESUMO

Trabecular bone is viscoelastic under dynamic loading. However, it is unclear how tissue viscoelasticity controls viscoelasticity at the apparent-level. In this study, viscoelasticity of cylindrical human trabecular bone samples (n=11, male, age 18-78 years) from 11 proximal femurs were characterized using dynamic and stress-relaxation testing at the apparent-level and with creep nanoindentation at the tissue-level. In addition, bone tissue elasticity was determined using scanning acoustic microscope (SAM). Tissue composition and collagen crosslinks were assessed using Raman micro-spectroscopy and high performance liquid chromatography (HPLC), respectively. Values of material parameters were obtained from finite element (FE) models by optimizing tissue-level creep and apparent-level stress-relaxation to experimental nanoindentation and unconfined compression testing values, respectively, utilizing the second order Prony series to depict viscoelasticity. FE simulations showed that tissue-level equilibrium elastic modulus (Eeq) increased with increasing crystallinity (r=0.730, p=.011) while at the apparent-level it increased with increasing hydroxylysyl pyridinoline content (r=0.718, p=.019). In addition, the normalized shear modulus g1 (r=-0.780, p=.005) decreased with increasing collagen ratio (amide III/CH2) at the tissue-level, but increased (r=0.696, p=.025) with increasing collagen ratio at the apparent-level. No significant relations were found between the measured or simulated viscoelastic parameters at the tissue- and apparent-levels nor were the parameters related to tissue elasticity determined with SAM. However, only Eeq, g2 and relaxation time τ1 from simulated viscoelastic values were statistically different between tissue- and apparent-levels (p<.01). These findings indicate that bone tissue viscoelasticity is affected by tissue composition but may not fully predict the macroscale viscoelasticity in human trabecular bone.


Assuntos
Osso Esponjoso/fisiologia , Fêmur/fisiologia , Adolescente , Adulto , Idoso , Colágeno/metabolismo , Simulação por Computador , Módulo de Elasticidade , Análise de Elementos Finitos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Viscosidade , Adulto Jovem
15.
Med Phys ; 43(5): 2030, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27147315

RESUMO

PURPOSE: The purpose of this study was to investigate the effect of simultaneous changes in cortical porosity, tissue mineral density, and elastic properties on radial speed of sound (SOS) in cortical bone. The authors applied quantitative pulse-echo (PE) ultrasound techniques that hold much potential especially for screening of osteoporosis at primary healthcare facilities. Currently, most PE measurements of cortical thickness, a well-known indicator of fracture risk, use a predefined estimate for SOS in bone to calculate thickness. Due to variation of cortical bone porosity, the use of a constant SOS value propagates to an unknown error in cortical thickness assessment by PE ultrasound. METHODS: The authors conducted 2.25 and 5.00 MHz focused PE ultrasound time of flight measurements on femoral diaphyses of 18 cadavers in vitro. Cortical porosities of the samples were determined using microcomputed tomography and related to SOS in the samples. Additionally, the effect of cortical bone porosity and mechanical properties of the calcified matrix on SOS was investigated using numerical finite difference time domain simulations. RESULTS: Both experimental measurements and simulations demonstrated significant negative correlation between radial SOS and cortical porosity (R(2) ≥ 0.493, p < 0.01 and R(2) ≥ 0.989, p < 0.01, respectively). When a constant SOS was assumed for cortical bone, the error due to variation of cortical bone porosity (4.9%-16.4%) was about 6% in the cortical thickness assessment in vitro. CONCLUSIONS: Use of a predefined, constant value for radial SOS in cortical bone, i.e., neglecting the effect of measured variation in cortical porosity, propagated to an error of 6% in cortical thickness. This error can be critical as characteristic cortical thinning of 1.10% ± 1.06% per yr decreases bending strength of the distal radius and results in increased fragility in postmenopausal women. Provided that the cortical porosity can be estimated in vivo, the relationship between radial SOS and cortical porosity can be utilized and a porosity based radial SOS estimate could be implemented to determine cortical thickness. This would constitute a step toward individualized quantitative ultrasound diagnostics of osteoporosis.


Assuntos
Osso Cortical/fisiologia , Fêmur/fisiologia , Ondas Ultrassônicas , Adulto , Idoso , Fenômenos Biomecânicos , Calcificação Fisiológica/fisiologia , Simulação por Computador , Osso Cortical/diagnóstico por imagem , Elasticidade , Feminino , Fêmur/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Tamanho do Órgão , Porosidade , Ultrassonografia , Microtomografia por Raio-X
16.
Rev Sci Instrum ; 87(11): 11D809, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910539

RESUMO

A systematic study of scintillation materials was undertaken to improve the time resolution of the fast ion diagnostic currently installed at TJ-II stellarator. It was found that YAP:Ce (formula YAlO3:Ce, Yttrium Aluminum Perovskite doped with Cerium) ionoluminescence offers better sensitivity and time response compared to the standard detector material, SrGa2S4:Eu (TG-Green), currently used in TJ-II. A comparison between both materials was carried out by irradiating them with H+ ions of up to 40 keV using a dedicated laboratory setup. It is found that for the low energy ions of interest at TJ-II, YAP:Ce offers 20 times higher sensitivity than TG-Green and much faster decay time, 27 ns versus 540 ns. It is expected that the use of YAP:Ce in combination with a faster data acquisition and an ion counting software as part of the TJ-II ion luminescent probe will provide 20 times faster data on ion loss.

17.
J Biomech ; 48(2): 269-75, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25498367

RESUMO

Trabecular bone is a metabolically active tissue with a high surface to volume ratio. It exhibits viscoelastic properties that may change during aging. Changes in bone properties due to altered metabolism are sensitively revealed in trabecular bone. However, the relationships between material composition and viscoelastic properties of bone, and their changes during aging have not yet been elucidated. In this study, trabecular bone samples from the femoral neck of male cadavers (n=21) aged 17-82 years were collected and the tissue level composition and its associations with the tissue viscoelastic properties were evaluated by using Raman microspectroscopy and nanoindentation, respectively. For composition, collagen content, mineralization, carbonate substitution and mineral crystallinity were evaluated. The calculated mechanical properties included reduced modulus (Er), hardness (H) and the creep parameters (E1, E2, η1and η2), as obtained by fitting the experimental data to the Burgers model. The results indicated that the creep parameters, E1, E2, η1and η2, were linearly correlated with mineral crystallinity (r=0.769-0.924, p<0.001). Creep time constant (η2/E2) tended to increase with crystallinity (r=0.422, p=0.057). With age, the mineralization decreased (r=-0.587, p=0.005) while the carbonate substitution increased (r=0.728, p<0.001). Age showed no significant associations with nanoindentation parameters. The present findings suggest that, at the tissue-level, the viscoelastic properties of trabecular bone are related to the changes in characteristics of bone mineral. This association may be independent of human age.


Assuntos
Elasticidade , Colo do Fêmur/citologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Fenômenos Biomecânicos , Densidade Óssea , Colágeno/metabolismo , Colo do Fêmur/metabolismo , Colo do Fêmur/fisiologia , Dureza , Humanos , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Viscosidade , Suporte de Carga , Adulto Jovem
18.
Blood Cancer J ; 5: e342, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26314984

RESUMO

An increasing numbers of patients are being diagnosed with asymptomatic early-stage chronic lymphocytic leukemia (CLL), with no treatment indication at baseline. We applied a high-throughput deep-targeted analysis, especially designed for covering widely TP53 and ATM genes, in 180 patients with inactive disease at diagnosis, to test the independent prognostic value of CLL somatic recurrent mutations. We found that 40/180 patients harbored at least one acquired variant with ATM (n=17, 9.4%), NOTCH1 (n=14, 7.7%), TP53 (n=14, 7.7%) and SF3B1 (n=10, 5.5%) as most prevalent mutated genes. Harboring one 'sub-Sanger' TP53 mutation granted an independent 3.5-fold increase of probability of needing treatment. Those patients with a double-hit ATM lesion (mutation+11q deletion) had the shorter median time to first treatment (17 months). We found that a genomic variable: TP53 mutations, most of them under the sensitivity of conventional techniques; a cell phenotypic factor: CD38-positive expression; and a classical marker as ß2-microglobulin, remained as the unique independent predictors of outcome. The high-throughput determination of TP53 status, particularly in this set of patients frequently lacking high-risk chromosomal aberrations, emerges as a key step, not only for prediction modeling, but also for exploring mutation-specific therapeutic approaches and minimal residual disease monitoring.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Mutação , Idoso , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genes Neoplásicos , Estudos de Associação Genética , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Prognóstico , Modelos de Riscos Proporcionais
19.
Gene ; 87(1): 127-31, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2185135

RESUMO

The cysD gene, involved in cysteine biosynthesis in Escherichia coli and Salmonella typhimurium, is positively regulated by the CysB regulatory protein. The cysD promoter of E. coli K-12 in a 492-bp PstI-Eco RI fragment was sequenced. The in vivo transcription start point (tsp) for the cysD gene was determined by the methods of T4 DNA polymerase mapping and mung-bean nuclease mapping. The -10 region of the cysD promoter (TATAGT) is closely homologous to the -10 consensus sequence (TATAAT) for E. coli promoters. The -35 region of this promoter (TTCATT) is less closely related to the -35 consensus sequence (TTGACA). Several mutants were obtained by using a chain-termination method for generating unidirectional deletions. Evidence is presented for a possible CysB protein binding site around -89, thought to be involved in regulation of expression of the cysD gene.


Assuntos
Cistina/biossíntese , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Regiões Promotoras Genéticas , Sequência de Aminoácidos , Sequência de Bases , Genes Reguladores , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Mapeamento por Restrição , Salmonella typhimurium/genética , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
20.
Gene ; 64(2): 207-15, 1988 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-2841194

RESUMO

Two promoter-detection vectors have been constructed which enable the cloning and characterization of promoters recognized by the RNA polymerase of Escherichia coli K-12. The intergenic region of phage M13 DNA, present in opposite orientations in the two vectors, permits the preparation of single-stranded DNA of either strand of the insert thus facilitating oligodeoxyribonucleotide heteroduplex mutagenesis and sequencing of both strands by the dideoxy method of chain termination. After mutagenesis, isolates can be screened for changed function by replica-plating colonies to plates containing XGal. Selected isolates can be characterized by nucleotide sequence analysis, to determine the change in structure, and by beta-galactosidase assays, thus measuring the effect of mutagenesis on promoter function. The vectors could also be used like other protein-fusion vectors.


Assuntos
Escherichia coli/genética , Vetores Genéticos , Regiões Promotoras Genéticas , Sequência de Bases , Clonagem Molecular , Colífagos/genética , Enzimas de Restrição do DNA , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Dados de Sequência Molecular , Mutação , Plasmídeos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA