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1.
medRxiv ; 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37333093

RESUMO

Background: Delirium following cardiac surgery is common, morbid, and costly, but may be prevented with risk stratification and targeted intervention. Preoperative protein signatures may identify patients at increased risk for worse postoperative outcomes, including delirium. In this study, we aimed to identify plasma protein biomarkers and develop a predictive model for postoperative delirium in older patients undergoing cardiac surgery, while also uncovering possible pathophysiological mechanisms. Methods: SOMAscan analysis of 1,305 proteins in the plasma from 57 older adults undergoing cardiac surgery requiring cardiopulmonary bypass was conducted to define delirium-specific protein signatures at baseline (PREOP) and postoperative day 2 (POD2). Selected proteins were validated in 115 patients using the ELLA multiplex immunoassay platform. Proteins were combined with clinical and demographic variables to build multivariable models that estimate the risk of postoperative delirium and bring light to the underlying pathophysiology. Results: A total of 115 and 85 proteins from SOMAscan analyses were found altered in delirious patients at PREOP and POD2, respectively (p<0.05). Using four criteria including associations with surgery, delirium, and biological plausibility, 12 biomarker candidates (Tukey's fold change (|tFC|)>1.4, Benjamini-Hochberg (BH)-p<0.01) were selected for ELLA multiplex validation. Eight proteins were significantly altered at PREOP, and seven proteins at POD2 (p<0.05), in patients who developed postoperative delirium compared to non-delirious patients. Statistical analyses of model fit resulted in the selection of a combination of age, sex, and three proteins (angiopoietin-2 (ANGPT2); C-C motif chemokine 5 (CCL5); and metalloproteinase inhibitor 1 (TIMP1); AUC=0.829) as the best performing predictive model for delirium at PREOP. The delirium-associated proteins identified as biomarker candidates are involved with inflammation, glial dysfunction, vascularization, and hemostasis, highlighting the multifactorial pathophysiology of delirium. Conclusion: Our study proposes a model of postoperative delirium that includes a combination of older age, female sex, and altered levels of three proteins. Our results support the identification of patients at higher risk of developing postoperative delirium after cardiac surgery and provide insights on the underlying pathophysiology. ClinicalTrials.gov ( NCT02546765 ).

2.
Int J Oral Maxillofac Surg ; 48(6): 810-823, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30442550

RESUMO

This study was performed to investigate sinus floor augmentation with two different particle sizes of demineralized bovine bone mineral (DBBM) by means of histological and immunohistochemical (IHC) analysis. A randomized clinical trial was conducted involving 10 individuals requiring two-stage bilateral maxillary sinus augmentation for implant installation. The patients were randomly divided into two groups following a split-mouth design: the maxillary sinus on one side was filled with small-sized particles (0.25-1mm) and on the contralateral side with large-sized particles (1-2mm). After a healing period of 8 months, 25 implants were placed. During implant site preparation, bone biopsies were obtained from each sinus, perpendicular to the long axis of the implant (buccal-palatal direction), for descriptive and histomorphometric analyses. IHC staining for protein expression of osteocalcin (OCN), vascular endothelial growth factor (VEGF), and tartrate-resistant acid phosphatase (TRAP) was also performed. Histomorphometric analysis revealed no statistically significant difference in the percentage of biomaterial (32.4±8.56% and 38.0±6.92%), newly formed bone (36.1±9.60% and 36.7±5.79%), or connective tissue (30.4±8.63% and 23.8±6.16%) between the small- and large-sized particle groups, respectively. IHC analysis did not reveal differences in the expression of OCN, VEGF, or TRAP. These findings suggest that both particle sizes of DBBM are effective for bone augmentation in the maxillary sinus.


Assuntos
Substitutos Ósseos , Levantamento do Assoalho do Seio Maxilar , Animais , Transplante Ósseo , Bovinos , Implantação Dentária Endóssea , Humanos , Seio Maxilar , Minerais , Tamanho da Partícula , Fator A de Crescimento do Endotélio Vascular
3.
Int J Oral Maxillofac Surg ; 45(12): 1556-1563, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27692642

RESUMO

The aim of this study was to compare implant stability after maxillary sinus floor augmentation using small- or large-sized particles of Bio-Oss. Ten partially edentulous patients requiring bilateral maxillary sinus floor augmentation were enrolled. The subjects were assigned randomly to one of two experimental groups: maxillary sinus was filled with 0.25-1mm particle size (small particles) and the contralateral side was filled with 1-2mm particle size (large particles). After 8 months, a total of 25 implants were placed in the two maxillary sinuses. Primary implant stability was measured immediately after implant placement (T0) using a torque controller and resonance frequency analysis (RFA). Six months after implant placement (T1), the implant stability was measured again. There were no postoperative complications in either particle size group, and the success rate for implant survival was 100%. All implants showed good primary stability as evidenced by high torque for the implant insertion in both groups. RFA revealed high ISQ values for all implants installed in both groups at T0 and T1. These results indicate that the size of the Bio-Oss particles (small and large) did not influence implant stability in the maxillary sinus. Indeed, small and large particles of Bio-Oss presented optimal properties, supporting their possible use as osteoconductive grafts.


Assuntos
Substitutos Ósseos/uso terapêutico , Seio Maxilar/cirurgia , Minerais/uso terapêutico , Levantamento do Assoalho do Seio Maxilar/métodos , Adulto , Idoso , Animais , Transplante Ósseo , Bovinos , Implantação Dentária Endóssea , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Estudos Prospectivos
4.
Mater Sci Eng C Mater Biol Appl ; 54: 196-206, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26046283

RESUMO

Titanium (Ti) is commonly used in dental implant applications. Surface modification strategies are being followed in last years in order to build Ti oxide-based surfaces that can fulfill, simultaneously, the following requirements: induced cell attachment and adhesion, while providing a superior corrosion and tribocorrosion performance. In this work micro-arc oxidation (MAO) was used as a tool for the growth of a nanostructured bioactive titanium oxide layer aimed to enhance cell attachment and adhesion for dental implant applications. Characterization of the surfaces was performed, in terms of morphology, topography, chemical composition and crystalline structure. Primary human osteoblast adhesion on the developed surfaces was investigated in detail by electronic and atomic force microscopy as well as immunocytochemistry. Also an investigation on the early cytokine production was performed. Results show that a relatively thick hybrid and graded oxide layer was produced on the Ti surface, being constituted by a mixture of anatase, rutile and amorphous phases where calcium (Ca) and phosphorous (P) were incorporated. An outermost nanometric-thick amorphous oxide layer rich in Ca was present in the film. This amorphous layer, rich in Ca, improved fibroblast viability and metabolic activity as well as osteoblast adhesion. High-resolution techniques allowed to understand that osteoblasts adhered less in the crystalline-rich regions while they preferentially adhere and spread over in the Ca-rich amorphous oxide layer. Also, these surfaces induce higher amounts of IFN-γ cytokine secretion, which is known to regulate inflammatory responses, bone microarchitecture as well as cytoskeleton reorganization and cellular spreading. These surfaces are promising in the context of dental implants, since they might lead to faster osseointegration.


Assuntos
Cálcio/química , Implantes Dentários , Adesão Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Citocinas/metabolismo , Humanos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Osseointegração , Osteoblastos/citologia , Osteoblastos/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Fósforo/química , Propriedades de Superfície , Titânio/química , Vimentina/genética , Vimentina/metabolismo
5.
Transplant Proc ; 47(2): 240-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25769556

RESUMO

BACKGROUND: Kidney transplantation rates in the United States are lower among African Americans than among whites. Well-documented racial disparities in access to transplantation explain some, but not all, of these differences. Prior survey-based research suggests that African American dialysis patients are less likely than whites to desire transplantation, but little research has focused on an in-depth exploration of preferences about kidney transplantation among African Americans. Thus, the purposes of this study were to explore preferences and to compare patients' expectations about transplantation with actual status on the transplant list. METHODS: We conducted semistructured interviews with 16 African Americans receiving chronic hemodialysis. We analyzed the interviews using the constant comparative method of qualitative analysis. We also reviewed the dialysis center's transplant list. RESULTS: Four dominant themes emerged: (1) varied desire for transplant; (2) concerns about donor source; (3) barriers to transplantation; and (4) lack of communication with nephrologists and the transplantation team. A thread of mistrust about equity in the transplantation process flowed through themes 2-4. In 7/16 cases, patients' understanding of their transplant listing status was discordant with their actual status. CONCLUSIONS: Our study suggests that many African Americans on hemodialysis are interested in kidney transplantation, but that interest is often tempered by concerns about transplantation, including misconceptions about the risks to recipients and donors. Mistrust about equity in the organ allocation process also contributed to ambivalence. The discordance between patients' perceptions of listing status and actual status suggests communication gaps between African American hemodialysis patients and physicians. Clinicians should avoid interpreting ambivalence about transplantation as lack of interest.


Assuntos
Negro ou Afro-Americano/psicologia , Transplante de Rim/psicologia , Preferência do Paciente/psicologia , Diálise Renal/psicologia , Confiança , Adulto , Idoso , Idoso de 80 Anos ou mais , Comunicação , Feminino , Disparidades em Assistência à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Preferência do Paciente/etnologia , Percepção , Pesquisa Qualitativa , Estados Unidos , População Branca
6.
Clin Oral Implants Res ; 24(4): 428-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22092825

RESUMO

AIM: Clinical data are scarce on flapless-guided surgery in the mandible using the all-on-four concept. In addition, limited documentation exists on the latter under immediate loading conditions with a pre-fabricated implant bridge. The aim was to provide detailed documentation focusing on clinical and radiographic outcome and complications. MATERIAL AND METHODS: Sixteen systemically healthy non-smoking patients (10 women, 6 men, average age 59 years) with sufficient bone volume in the mandible were operated via flapless-guided surgery using the all-on-four concept. Clinical and radiographic data and complications were registered at 3, 6 and 12 months. RESULTS: The overall implant survival rate was 90% with a trend for higher failure of short implants (P = 0.098). The mean bone level after 12 months of function was 0.83 mm with a maximum of 1.07 mm. Technical complications were common (15/16 patients). These mainly related to a misfit between the pre-fabricated prosthesis and abutment(s) (13/16 patients). CONCLUSION: If immediate loading of implants is pursued fabrication of the implant bridge should be based on actual impression of the implants at the time of surgery and not on their virtual position.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário/métodos , Mandíbula/cirurgia , Idoso , Dente Suporte , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Radiografia , Resultado do Tratamento
7.
Acta Anaesthesiol Scand ; 54(6): 663-77, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20397979

RESUMO

Post-operative cognitive dysfunction (POCD) is a decline in cognitive function from pre-operative levels, which has been frequently described after cardiac surgery. The purpose of this study was to examine the variability in the measurement and definitions for POCD using the framework of a 1995 Consensus Statement on measurement of POCD. Electronic medical literature databases were searched for the intersection of the search terms 'thoracic surgery' and 'cognition, dementia, and neuropsychological test.' Abstracts were reviewed independently by two reviewers. English articles with >50 participants published since 1995 that performed pre-operative and post-operative psychometric testing in patients undergoing cardiac surgery were reviewed. Data relevant to the measurement and definition of POCD were abstracted and compared with the recommendations of the Consensus Statement. Sixty-two studies of POCD in patients undergoing cardiac surgery were identified. Of these studies, the recommended neuropsychological tests were carried out in less than half of the studies. The cognitive domains measured most frequently were attention (n=56; 93%) and memory (n=57; 95%); motor skills were measured less frequently (n=36; 60%). Additionally, less than half of the studies examined anxiety and depression, performed neurological exam, or accounted for learning. Four definitions of POCD emerged: per cent decline (n=15), standard deviation decline (n=14), factor analysis (n=13), and analysis of performance on individual tests (n=12). There is marked variability in the measurement and definition of POCD. This heterogeneity may impede progress by reducing the ability to compare studies on the causes and treatment of POCD.


Assuntos
Procedimentos Cirúrgicos Cardíacos/psicologia , Transtornos Cognitivos/diagnóstico , Testes Neuropsicológicos , Complicações Pós-Operatórias/diagnóstico , Idoso , Transtornos Cognitivos/etiologia , Conferências de Consenso como Assunto , Ponte de Artéria Coronária/psicologia , Fidelidade a Diretrizes , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Guias de Prática Clínica como Assunto , Padrões de Referência
8.
Neurology ; 72(18): 1570-5, 2009 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-19414723

RESUMO

OBJECTIVE: To examine the impact of delirium on the trajectory of cognitive function in a cohort of patients with Alzheimer disease (AD). METHODS: A secondary analysis of data collected from a large prospective cohort, the Massachusetts Alzheimer's Disease Research Center's patient registry, examined cognitive performance over time in patients who developed (n = 72) or did not develop (n = 336) delirium during the course of their illnesses. Cognitive performance was measured by change in score on the Information-Memory-Concentration (IMC) subtest of the Blessed Dementia Rating Scale. Delirium was identified using a previously validated chart review method. Using linear mixed regression models, rates of cognitive change were calculated, controlling for age, sex, education, comorbid medical diagnoses, family history of dementia, dementia severity score, and duration of symptoms before diagnosis. RESULTS: A significant acceleration in the slope of cognitive decline occurs following an episode of delirium. Among patients who developed delirium, the average decline at baseline for performance on the IMC was 2.5 points per year, but after an episode of delirium there was further decline to an average of 4.9 points per year (p = 0.001). Across groups, the rate of change in IMC score occurred about three times faster in those who had delirium compared to those who did not. CONCLUSIONS: Delirium can accelerate the trajectory of cognitive decline in patients with Alzheimer disease (AD). The information from this study provides the foundation for future randomized intervention studies to determine whether prevention of delirium might ameliorate or delay cognitive decline in patients with AD.


Assuntos
Doença de Alzheimer/epidemiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Delírio/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Estudos de Coortes , Comorbidade , Delírio/prevenção & controle , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Massachusetts , Testes Neuropsicológicos , Estudos Prospectivos , Sistema de Registros , Caracteres Sexuais , Fatores de Tempo
9.
Oral Dis ; 15(2): 148-54, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19036054

RESUMO

OBJECTIVE: The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential. METHODS: Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer (n = 5 patients) and control group--autogenous bone only (n = 13 patients). RESULTS: In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA (P < 0.001) and CP in relation to control (P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups (P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP (P < 0.001). CONCLUSION: Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized.


Assuntos
Processo Alveolar/fisiologia , Substitutos Ósseos/uso terapêutico , Maxila/fisiologia , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Processo Alveolar/irrigação sanguínea , Processo Alveolar/cirurgia , Aumento do Rebordo Alveolar/métodos , Materiais Biocompatíveis/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Fosfatos de Cálcio/uso terapêutico , Humanos , Hidroxiapatitas/uso terapêutico , Maxila/irrigação sanguínea , Maxila/cirurgia , Seio Maxilar/irrigação sanguínea , Seio Maxilar/fisiologia , Seio Maxilar/cirurgia , Microvasos/efeitos dos fármacos , Microvasos/crescimento & desenvolvimento , Neovascularização Fisiológica/fisiologia , Osseointegração/fisiologia , Resinas Vegetais/uso terapêutico , Ricinus
10.
Anaesthesia ; 63(9): 941-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18547292

RESUMO

The purpose of this analysis was to determine if postoperative delirium was associated with early postoperative cognitive dysfunction (at 7 days) and long-term postoperative cognitive dysfunction (at 3 months). The International Study of Postoperative Cognitive Dysfunction recruited 1218 subjects >or= 60 years old undergoing elective, non-cardiac surgery. Postoperatively, subjects were evaluated for delirium using the criteria of the Diagnostic and Statistical Manual. Subjects underwent neuropsychological testing pre-operatively and postoperatively at 7 days (n = 1018) and 3 months (n = 946). Postoperative cognitive dysfunction was defined as a composite Z-score > 2 across tests or at least two individual test Z-scores > 2. Subjects with delirium were significantly less likely to participate in postoperative testing. Delirium was associated with an increased incidence of early postoperative cognitive dysfunction (adjusted risk ratio 1.6, 95% CI 1.1-2.1), but not long-term postoperative cognitive dysfunction (adjusted risk ratio 1.3, 95% CI 0.6-2.4). Delirium was associated with early postoperative cognitive dysfunction, but the relationship of delirium to long-term postoperative cognitive dysfunction remains unclear.


Assuntos
Transtornos Cognitivos/etiologia , Delírio/etiologia , Complicações Pós-Operatórias , Idoso , Transtornos Cognitivos/epidemiologia , Delírio/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Prognóstico , Medição de Risco
11.
J Periodontal Res ; 42(5): 466-73, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17760825

RESUMO

BACKGROUND AND OBJECTIVE: Cyclosporine A is an immunosuppressive drug that is widely used in organ transplant patients as well as to treat a number of autoimmune conditions. Bone loss is reported as a significant side-effect of cyclosporine A use because this can result in serious morbidity of the patients. As we have shown that cyclosporine A-associated bone loss can also affect the alveolar bone, the purpose of this study was to evaluate the effect of the concomitant administration of alendronate on alveolar bone loss in a rat model. MATERIAL AND METHODS: Forty Wistar rats (10 per group) were given cyclosporine A (10 mg/kg, daily), alendronate (0.3 mg/kg, weekly), or both cyclosporine A and alendronate, for 60 d. The control group received daily injections of sterile saline. The expression of proteins associated with bone turnover, including osteocalcin, alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP), and also the calcium levels, were evaluated in the serum. Analysis of the bone volume, alveolar bone surface, the number of osteoblasts per bone surface and the number of osteoclasts per bone surface around the lower first molars was also performed. RESULTS: The results indicate that cyclosporine A treatment was associated with bone resorption, represented by a decrease in the bone volume, alveolar bone surface and the number of osteoblasts per bone surface and by an increase in the number of osteoclasts per bone surface and TRAP-5b. These effects were effectively counteracted by concomitant alendronate administration. CONCLUSION: It is concluded that concomitant administration of alendronate can prevent cyclosporine A-associated alveolar bone loss.


Assuntos
Alendronato/uso terapêutico , Perda do Osso Alveolar/induzido quimicamente , Conservadores da Densidade Óssea/uso terapêutico , Ciclosporina/efeitos adversos , Imunossupressores/efeitos adversos , Fosfatase Ácida/sangue , Alendronato/administração & dosagem , Fosfatase Alcalina/sangue , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Processo Alveolar/efeitos dos fármacos , Processo Alveolar/patologia , Animais , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Cálcio/sangue , Contagem de Células , Modelos Animais de Doenças , Isoenzimas/sangue , Masculino , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteocalcina/sangue , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato
12.
J Periodontal Res ; 39(3): 143-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15102042

RESUMO

OBJECTIVES: The administration of cyclosporin A has been associated with significant bone loss and increased bone remodeling. The present investigation was designed to evaluate the effects of cyclosporin A on alveolar bone of rats subjected to experimental periodontitis, using serum, stereometric and radiographic analysis. METHODS: Twenty-four rats were divided into one of the following groups with six animals each: group I, control rats; group II, in which the animals received a cotton ligature around the lower first molars; group III, in which the rats received a cotton ligature around the lower first molars and were treated with 10 mg/(kg body weight day) of cyclosporin A; group IV, in which the rats were treated with 10 mg/(kg body weight day) of cyclosporin A. At the end of experimental period, at 30 days, animals were killed and the serum calcium and alkaline phosphatase levels were measured in all groups. The distance from the alveolar bone crest to the cemento-enamel junction was measured radiographically for each mesial surface of the lower first molars of each rat. After histological processing, the stereological parameters: volume densities of multinucleated osteoclasts (V(o)), alveolar bone (V(b)), marrow (V(m)), and relation of eroded surface/bone surface (Es/Bs) were assessed at the mesial region of the alveolar bone. RESULTS: Significant decreases in serum calcium were observed in those groups that received cyclosporin A therapy. No significant changes in serum alkaline phosphatase were observed. The therapy with cyclosporin A combined with the ligature placement decreased the V(b) and increased the V(o), V(m) and Es/Bs at the mesial surface of lower first molars. On the other hand, the radiographic data showed that cyclosporin A therapy diminished the alveolar bone loss at the mesial surface of the lower first molars. CONCLUSIONS: Therefore, within the limits of this study, we suggest that cyclosporin A at immunosuppressive levels can bring about an imbalance in the alveolar bone homeostasis in rats. However, in the presence of inflammatory stimulation, the inhibition of the immune system by cyclosporin A may decrease the initial periodontal breakdown.


Assuntos
Perda do Osso Alveolar/induzido quimicamente , Remodelação Óssea/efeitos dos fármacos , Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Periodontite , Fosfatase Alcalina/sangue , Perda do Osso Alveolar/sangue , Perda do Osso Alveolar/diagnóstico por imagem , Análise de Variância , Animais , Densidade Óssea/efeitos dos fármacos , Cálcio/sangue , Ciclosporina/efeitos adversos , Modelos Animais de Doenças , Imunossupressores/efeitos adversos , Ligadura , Periodontite/tratamento farmacológico , Radiografia , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas
14.
J Immunol ; 167(7): 3715-24, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11564787

RESUMO

T cells express a variety of surface proteins as they develop to maturity in the thymus. In addition to the TCR-CD3 complex and the two major coreceptors, CD4 and CD8, other surface proteins expressed include receptors for cytokines, growth factors, counterreceptors, and extracellular matrix molecules. To determine the role of integrin adhesion receptors in T cell development, we have expressed a trans-dominant inhibitor of integrin function in the thymus. This inhibitor leads to a block of adhesion to fibronectin due to reduced activation of integrin receptors. This reduced adhesion leads to a partial block in differentiation from CD4-CD8- cells to CD4+CD8+ cells, after the CD25+ stage, suggesting that integrins are important during Lck-mediated differentiation. Furthermore, the overall production of CD4+ cells is reduced compared with that of CD8+ cells without changes in negative selection, suggesting that integrins may be involved in the determination of the fate of the cell as well. These results demonstrate that integrin receptor function is required for proper thymocyte development in vivo.


Assuntos
Integrinas/fisiologia , Timo/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Adesão Celular , Diferenciação Celular , Células Cultivadas , Dosagem de Genes , Integrina beta1/genética , Integrina beta1/fisiologia , Integrinas/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Subpopulações de Linfócitos T/classificação , Timo/embriologia , Timo/crescimento & desenvolvimento
15.
JAMA ; 286(3): 309-14, 2001 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-11466096

RESUMO

CONTEXT: Right heart catheterization (RHC) is commonly performed before high-risk noncardiac surgery, but the benefit of this strategy remains unproven. OBJECTIVE: To evaluate the relationship between use of perioperative RHC and postoperative cardiac complication rates in patients undergoing major noncardiac surgery. DESIGN: Prospective, observational cohort study. SETTING: Tertiary care teaching hospital in the United States. PATIENTS: Patients (n = 4059 aged >/=50 years) who underwent major elective noncardiac procedures with an expected length of stay of 2 or more days between July 18, 1989, and February 28, 1994. Two hundred twenty one patients had RHC and 3838 did not. MAIN OUTCOME MEASURE: Combined end point of major postoperative cardiac events, including myocardial infarction, unstable angina, cardiogenic pulmonary edema, ventricular fibrillation, documented ventricular tachycardia or primary cardiac arrest, and sustained complete heart block, classified by a reviewer blinded to preoperative data. RESULTS: Major cardiac events occurred in 171 patients (4.2%). Patients who underwent perioperative RHC had a 3-fold increase in incidence of major postoperative cardiac events (34 [15.4%] vs 137 [3.6%]; P<.001). In multivariate analyses, the adjusted odds ratios (ORs) for postoperative major cardiac and noncardiac events in patients undergoing RHC were 2.0 (95% confidence interval [CI], 1.3-3.2) and 2.1 (95% CI, 1.2-3.5), respectively. In a case-control analysis of a subset of 215 matched pairs of patients who did and did not undergo RHC, adjusted for propensity of RHC and type of procedure, patients who underwent perioperative RHC also had increased risk of postoperative congestive heart failure (OR, 2.9; 95% CI, 1.4-6.2) and major noncardiac events (OR, 2.2; 95% CI, 1.4-4.9). CONCLUSIONS: No evidence was found of reduction in complication rates associated with use of perioperative RHC in this population. Because of the morbidity and the high costs associated with RHC, the impact of this intervention in perioperative care should be evaluated in randomized trials.


Assuntos
Cateterismo de Swan-Ganz , Procedimentos Cirúrgicos Eletivos , Cardiopatias/epidemiologia , Assistência Perioperatória , Complicações Pós-Operatórias/epidemiologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Risco
16.
J Am Geriatr Soc ; 49(5): 516-22, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11380742

RESUMO

OBJECTIVES: Delirium (or acute confusional state) affects 35% to 65% of patients after hip-fracture repair, and has been independently associated with poor functional recovery. We performed a randomized trial in an orthopedic surgery service at an academic hospital to determine whether proactive geriatrics consultation can reduce delirium after hip fracture. DESIGN: Prospective, randomized, blinded. SETTING: Inpatient academic tertiary medical center. PARTICIPANTS: 126 consenting patients 65 and older (mean age 79 +/- 8 years, 79% women) admitted emergently for surgical repair of hip fracture. MEASUREMENTS: Detailed assessment through interviews with patients and designated proxies and review of medical records was performed at enrollment to ascertain prefracture status. Subjects were then randomized to proactive geriatrics consultation, which began preoperatively or within 24 hours of surgery, or "usual care." A geriatrician made daily visits for the duration of the hospitalization and made targeted recommendations based on a structured protocol. To ascertain study outcomes, all subjects underwent daily, blinded interviews for the duration of their hospitalization, including the Mini-Mental State Examination (MMSE), the Delirium Symptom Interview (DSI), and the Memorial Delirium Assessment Scale (MDAS). Delirium was diagnosed using the Confusion Assessment Method (CAM) algorithm. RESULTS: The 62 patients randomized to geriatrics consultation were not significantly different (P>.1) from the 64 usual-care patients in terms of age, gender, prefracture dementia, comorbidity, type of hip fracture, or type of surgical repair. Sixty-one percent of geriatrics consultation patients were seen preoperatively and all were seen within 24 hours postoperatively. A mean of 10 recommendations were made throughout the duration of the hospitalization, with 77% adherence by the orthopedics team. Delirium occurred in 20 /62 (32%) intervention patients, versus 32 / 64 (50%) usual-care patients (P =.04), representing a relative risk of 0.64 (95% confidence interval (CI) = 0.37-0.98) for the consultation group. One case of delirium was prevented for every 5.6 patients in the geriatrics consultation group. There was an even greater reduction in cases of severe delirium, occurring in 7/ 60 (12%) of intervention patients and 18 / 62 (29%) of usual-care patients, with a relative risk of 0.40 (95% CI = 0.18-0.89). Despite this reduction in delirium, length of stay did not significantly differ between intervention and usual-care groups (median +/- interquartile range = 5 +/- 2 days in both groups), likely because protocols and pathways predetermined length of stay. In subgroup analyses, geriatrics consultation was most effective in reducing delirium in patients without prefracture dementia or activities of daily living (ADL) functional impairment. CONCLUSIONS: Proactive geriatrics consultation was successfully implemented with good adherence after hip-fracture repair. Geriatrics consultation reduced delirium by over one-third, and reduced severe delirium by over one-half. Our trial provides strong preliminary evidence that proactive geriatrics consultation may play an important role in the acute hospital management of hip-fracture patients.


Assuntos
Delírio/etiologia , Delírio/prevenção & controle , Avaliação Geriátrica , Geriatria/métodos , Fraturas do Quadril/cirurgia , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Encaminhamento e Consulta , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Delírio/classificação , Delírio/diagnóstico , Feminino , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Entrevista Psiquiátrica Padronizada , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Método Simples-Cego , Inquéritos e Questionários
17.
Ann Intern Med ; 134(8): 637-43, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11304103

RESUMO

BACKGROUND: Major surgical procedures are performed with increasing frequency in elderly persons, but the impact of age on resource use and outcomes is uncertain. OBJECTIVE: To evaluate the influence of age on perioperative cardiac and noncardiac complications and length of stay in patients undergoing noncardiac surgery. DESIGN: Prospective cohort study. SETTING: Urban academic medical center. PATIENTS: Consecutive sample of 4315 patients 50 years of age or older who underwent nonemergent major noncardiac procedures. MEASUREMENTS: Major perioperative complications (cardiac and noncardiac), in-hospital mortality, and length of stay. RESULTS: Major perioperative complications occurred in 4.3% (44 of 1015) of patients 59 years of age or younger, 5.7% (93 of 1646) of patients 60 to 69 years of age, 9.6% (129 of 1341) of patients 70 to 79 years of age, and 12.5% (39 of 313) of patients 80 years of age or older (P < 0.001). In-hospital mortality was significantly higher in patients 80 years of age or older than in those younger than 80 years of age (0.7% vs. 2.6%, respectively). Multivariate analyses indicated an increased odds ratio for perioperative complications or in-hospital mortality in patients 70 to 79 years of age (1.8 [95% CI, 1.2 to 2.7]) and those 80 years of age or older (OR, 2.1 [CI, 1.2 to 3.6]) compared with patients 50 to 59 years of age. Patients 80 years of age or older stayed an average of 1 day more in the hospital, after adjustment for other clinical data (P = 0.001). CONCLUSIONS: Elderly patients had a higher rate of major perioperative complications and mortality after noncardiac surgery and a longer length of stay, but even in patients 80 years of age or older, mortality was low.


Assuntos
Fatores Etários , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Tempo de Internação , Complicações Pós-Operatórias/mortalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Análise de Regressão , Estatísticas não Paramétricas
18.
J Mater Sci Mater Med ; 12(3): 273-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15348312

RESUMO

Titanium alloys are hoped to be used much more for applications as implant materials in the medical and dental fields because of their basic properties, such as biocompatibility, corrosion resistance and specific strength compared with other metallic implant materials. Thus, the Ti-6Al-7Nb alloy that has recently been developed for biomedical use, that is, primarily developed for orthopaedic use, is to be studied in this paper, for application in dental implants. The biocompatibility test in vivo was carried out in dogs and the osseointegration was verified through histological analysis of the samples of the Ti-6Al-7Nb alloy with and without hydroxyapatite coating that were inserted in the alveoli. Within the controlled conditions the samples did not show any toxic effects on the cells.

19.
J Periodontol ; 71(9): 1441-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11022773

RESUMO

BACKGROUND: Various procedures have been proposed to treat gingival recession, but few studies compare these procedures to each other. The purpose of this study was to evaluate a clinical comparison of subepithelial connective tissue graft (SCTG) and guided tissue regeneration (GTR) with a collagen membrane in the treatment of gingival recessions in humans. METHODS: Twenty-four defects were treated in 12 patients who presented canine or pre-molar Miller Class I and/or II bilateral gingival recessions. Both treatments were performed in all patients, and clinical measurements were obtained at baseline and 18 months after surgery. These clinical measurements included gingival recession height (GR), root coverage (RC), probing depth (PD), keratinized tissue width (KT), and final esthetic result. RESULTS: Both SCTG and GTR with a bioabsorbable membrane and bone graft demonstrated significant clinical and esthetic improvement for gingival recession coverage. The SCTG group was statistically significantly better than GTR for height of GR (SCTG = 0.2 mm, GTR = 1.12 mm, P= 0.02) and KT (SCTG = 4.58 mm, GTR = 2.5 mm, P<0.0001). However, PD was statistically significantly better for GTR than SCTG treatment (GTR = 1.66 mm, SCTG = 1.00, P= 0.01). The 2 procedures were statistically similar in root coverage (SCTG = 95.6%, GTR = 84.2%, P= 0.073). The esthetic condition after both treatments was satisfactory (P= 0.024). CONCLUSIONS: It was concluded that the gingival recessions treated with the SCTG group were superior for GR, RC, and KT clinical parameters, while GTR demonstrated better PD reduction. The final esthetic results were similar using both techniques.


Assuntos
Gengiva/transplante , Retração Gengival/cirurgia , Regeneração Tecidual Guiada Periodontal , Procedimentos Cirúrgicos Bucais/métodos , Implantes Absorvíveis , Adulto , Colágeno , Tecido Conjuntivo/transplante , Estética Dentária , Feminino , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Satisfação do Paciente , Retalhos Cirúrgicos , Resultado do Tratamento
20.
J Periodontol ; 71(5): 775-84, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10872959

RESUMO

BACKGROUND: The poor predictability of periodontal regenerative treatment of Class III furcation defects stimulates the study of alternatives to improve its results, such as the use of polypeptide growth factors. The objective of this study was to evaluate, both histologically and histometrically, the effects of topical application of basic fibroblast growth factor (b-FGF) associated with guided tissue regeneration (GTR) in the treatment of Class III defects surgically induced in dogs. METHODS: All second and fourth premolars of 5 mongrel dogs were used and randomly assigned to one of three treatment groups: group 1 (control), treated with scaling and root planing, tetracycline hydrochloride (125 mg/ml) conditioning, and GTR with a collagen membrane; group 2, same treatment as group 1 plus 0.5 mg of b-FGF; group 3, same treatment as group 1 plus 1.0 mg of b-FGF. After a 90-day healing period, routine histologic processing and staining with hematoxylin and eosin and Masson trichrome were performed. RESULTS: The descriptive analysis indicated better regenerative results in both groups treated with b-FGF while the histometric data, analyzed by means of analysis of variance (ANOVA), showed greater filling of the defects in group 2 in comparison to the defects in groups 3 and 1, respectively, which was represented by a smaller area of plaque-occupied space (P = 0.004) as well as a greater amount of newly formed cementum (P = 0.002). CONCLUSIONS: These results indicate that b-FGF, especially in smaller doses, may enhance the regenerative results in Class III furcation lesions, leading to greater filling of these defects with both mineralized and non-mineralized tissues.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Cemento Dentário/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Defeitos da Furca/tratamento farmacológico , Regeneração Tecidual Guiada Periodontal/métodos , Análise de Variância , Animais , Cães , Fator 2 de Crescimento de Fibroblastos/farmacologia , Defeitos da Furca/cirurgia , Análise Multivariada , Distribuição Aleatória , Estatísticas não Paramétricas
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