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1.
Eur J Orthop Surg Traumatol ; 34(2): 1057-1064, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37907769

RESUMO

PURPOSE: Polyethylene particles produced from metal-backed tibial (MBT) implants are understood to contribute to bone loss and component loosening. This, along with advanced surgical techniques, improved materials and increasing costs, has renewed interest in all-polyethylene tibias (APTs). We investigated peri-APT bone mineral density (BMD) in patients, expecting to find no differences between two post-operative values. METHODS: Patients over 65 years, with BMI ≤ 37.5 kg/m2 and no previous joint replacements were recruited to have computer-navigated total knee arthroplasty using an APT. The study cohort (n = 27) had mean age of 71.9 (SD 4.35) and BMI of 31.2 (SD 3.8). The BMD examinations were performed 6 weeks and 18 months post-operatively. Six regions of interest (ROI) were identified on anterior/posterior and lateral dual-energy X-ray absorptiometry scans. For each ROI, BMD relative differences (RDs) were determined between limbs and RDs at the two time points were compared. RESULTS: No differences were found between the RDs for any ROI. No revisions or complications were reported. At 18 months post-operatively, 79.2% of the cohort were very satisfied or satisfied with the outcome of their surgery and Oxford Knee Scores improved significantly compared to pre-operatively (p < 0.001). Mean knee range of motion was 102° (SD 10.7°), and mean leg alignment was 2.0° valgus (1-6°valgus). CONCLUSION: Results from BMD analysis suggest that implants were well fixated without compromising function. We believe that using APTs with computer navigation is a viable cheaper option to MBTs for patients who are less active, have lower BMI and good bone quality.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Humanos , Idoso , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Densidade Óssea , Polietileno , Prótese do Joelho/efeitos adversos , Tíbia/cirurgia , Desenho de Prótese , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia
2.
Am J Physiol Endocrinol Metab ; 325(1): E99-E105, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37285597

RESUMO

Low circulating levels of insulin-like growth-factor binding protein-2 (IGFBP-2) have been associated with increased adiposity and metabolic alterations such as insulin resistance, dyslipidemia, and nonalcoholic fatty liver disease in individuals with obesity. However, whether IGFBP-2 affects energy metabolism in the early stages of these disorders remains unclear. Herein, we hypothesized that plasma IGFBP-2 concentrations are inversely associated with early liver fat accumulation and alterations in lipid and glucose homeostasis in apparently healthy and asymptomatic men and women. Three hundred thirty-three middle-aged Caucasian men and women apparently healthy and without cardiovascular symptoms were enrolled for a cross-sectional cardiometabolic imaging study. Individuals with BMI ≥ 40 kg/m2, cardiovascular disease, dyslipidemia, hypertension, and diabetes were excluded. Fasting glucose and lipid profiles were measured and an oral glucose tolerance test was performed. Liver fat content was assessed by magnetic resonance spectroscopy. Volume of visceral adipose tissue (VAT) was evaluated by magnetic resonance imaging. Plasma IGFBP-2 levels were quantified by ELISA. Participants with low IGFBP-2 levels were characterized by a higher body fat mass (P < 0.0001), insulin resistance (P < 0.0001), higher plasma triglyceride (TG) (P < 0.0001), and lower HDL-cholesterol levels (P < 0.0001) in a sex-independent manner. IGFBP-2 levels were inversely correlated with hepatic fat fraction in both men (r = -0.36, P < 0.0001) and women (r = -0.40, P < 0.0001). IGFBP-2 concentrations were negatively associated with hepatic fat fraction independently of age and VAT in both men (R2 = 0.23, P = 0.012) and women (R2 = 0.27, P = 0.028). In conclusion, our findings show that even in asymptomatic, apparently healthy individuals, low IGFBP-2 levels are associated with a more deteriorated cardiometabolic risk profile and with a high hepatic fat content in a VAT-independent manner. However, IGFBP-2 does not appear to influence the established sexual dimorphism observed for metabolic variables and hepatic fat fraction. Additional studies are required to better understand the relationships between IGFBP-2 and liver fat content.NEW & NOTEWORTHY Faced with a paucity of reliable clinical etiologic markers for fatty liver, this research article demonstrates, for the first time, that low blood levels of the protein IGFBP-2 are associated with a more deteriorated cardiometabolic risk profile and with a high hepatic fat content independently of visceral fat volume and sex, even in asymptomatic, apparently healthy individuals.


Assuntos
Doenças Cardiovasculares , Hipercolesterolemia , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Estudos Transversais , Obesidade/metabolismo , Triglicerídeos/metabolismo , Fígado/diagnóstico por imagem , Fígado/metabolismo , Hipercolesterolemia/metabolismo , Doenças Cardiovasculares/metabolismo , Glucose/metabolismo , Metaboloma , Gordura Intra-Abdominal/metabolismo
3.
Eur J Orthop Surg Traumatol ; 33(4): 919-925, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35182238

RESUMO

PURPOSE: Venous thromboembolism (VTE) is a significant complication following lower limb arthroplasty (LLA). There is a paucity of evidence with regard to air travel following LLA. Orthopaedic surgeons are often asked by patients regarding air travel following LLA, and there is a need for evidence to guide these patients. METHODS: This was a retrospective cohort study. We identified two cohorts, one travelling to and from the hospital by air and another, by land. All patients received routine preoperative and post-operative care, and thromboprophylaxis, as per our hospital guidelines. We collected baseline demographics, ASA score and incidence of VTE at 90 days using local patient records and a national joint registry. We also recorded data on flight time and overland distance of travel. RESULTS: Two hundred and forty-three patients travelled by air; mean flight time was 74 min. In total, 5498 patients travelled a mean 25.3 miles over land to the hospital. No differences in baseline demographics or ASA score were observed. Four patients developed a VTE in the flight group, with 32 patients suffering a VTE in the control group. There was a significant difference in the VTE rate between the flight and control groups (p < 0.05); the relative risk of developing a VTE in the flight group was 2.85. CONCLUSIONS: In our cohort, perioperative short haul air travel is associated with an increased risk of VTE at 90 days following LLA. Orthopaedic surgeons must ensure that their patients are cognizant of the risks associated with perioperative air travel and take measures to minimise these risks.


Assuntos
Viagem Aérea , Artroplastia do Joelho , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Estudos Retrospectivos , Viagem , Artroplastia do Joelho/efeitos adversos , Fatores de Risco , Complicações Pós-Operatórias/etiologia
4.
J Lipid Res ; 63(10): 100269, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36030928

RESUMO

Low circulating concentrations of insulin-like growth factor binding protein-2 (IGFBP-2) have been associated with dyslipidemia, notably with high triglyceride (TG) levels. However, the determinants by which IGFBP-2 influences lipoprotein metabolism, especially that of TG-rich lipoproteins (TRLs), are poorly understood. Here, we aimed to assess the relationships between IGFBP-2 levels and lipoprotein production and catabolism in human subjects. Fasting IGFBP-2 concentrations were measured in the plasma of 219 men pooled from previous lipoprotein kinetics studies. We analyzed production rate and fractional catabolic rates of TRLapoB-48, and LDL-, IDL-, and VLDLapoB-100 by multicompartmental modeling of l-[5,5,5-D3] leucine enrichment data after a 12 h primed constant infusion in individuals kept in a constant nutritional steady state. Subjects had an average BMI of 30 kg/m2, plasma IGFBP-2 levels of 157 ng/ml, and TG of 2.2 mmol/l. After adjustments for age and BMI, IGFBP-2 levels were negatively associated with plasma TG (r = -0.29; P < 0.0001) and positively associated with HDL-cholesterol (r = 0.26; P < 0.0001). In addition, IGFBP-2 levels were positively associated with the fractional catabolic rate of VLDLapoB-100 (r = 0.20; P < 0.01) and IDLapoB-100 (r = 0.19; P < 0.05) and inversely with the production rate of TRLapoB-48 (r = -0.28; P < 0.001). These correlations remained statistically significant after adjustments for age, BMI, and the amount of fat given during the tracer infusion. These findings show that the association between low plasma IGFBP-2 and high TG concentrations could be due to both an impaired clearance of apoB-100-containing VLDL and IDL particles and an increased production of apoB-48-containing chylomicrons. Additional studies are necessary to investigate whether and how IGFBP-2 directly impacts the kinetics of TRL.


Assuntos
Apolipoproteínas B , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina , Humanos , Masculino , Apolipoproteína B-100/metabolismo , Apolipoproteína B-48/metabolismo , Apolipoproteínas B/metabolismo , HDL-Colesterol/metabolismo , Quilomícrons/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Cinética , Leucina , Lipoproteínas/metabolismo , Lipoproteínas VLDL/metabolismo , Triglicerídeos
5.
Immun Ageing ; 18(1): 8, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622333

RESUMO

BACKGROUND: The resident immune population of pancreatic islets has roles in islet development, beta cell physiology, and the pathology of diabetes. These roles have largely been attributed to islet macrophages, comprising 90% of islet immune cells (in the absence of islet autoimmunity), and, in the case of type 1 diabetes, to infiltrating autoreactive T cells. In adipose, tissue-resident and recruited T and B cells have been implicated in the development of insulin resistance during diet-induced obesity and ageing, but whether this is paralleled in the pancreatic islets is not known. Here, we investigated the non-macrophage component of resident islet immune cells in islets isolated from C57BL/6 J male mice during ageing (3 to 24 months of age) and following similar weight gain achieved by 12 weeks of 60% high fat diet. Immune cells were also examined by flow cytometry in cadaveric non-diabetic human islets. RESULTS: Immune cells comprised 2.7 ± 1.3% of total islet cells in non-diabetic mouse islets, and 2.3 ± 1.7% of total islet cells in non-diabetic human islets. In 3-month old mice on standard diet, B and T cells each comprised approximately 2-4% of the total islet immune cell compartment, and approximately 0.1% of total islet cells. A similar amount of T cells were present in non-diabetic human islets. The majority of islet T cells expressed the αß T cell receptor, and were comprised of CD8-positive, CD4-positive, and regulatory T cells, with a minor population of γδ T cells. Interestingly, the number of islet T cells increased linearly (R2 = 0.9902) with age from 0.10 ± 0.05% (3 months) to 0.38 ± 0.11% (24 months) of islet cells. This increase was uncoupled from body weight, and was not phenocopied by a degree similar weight gain induced by high fat diet in mice. CONCLUSIONS: This study reveals that T cells are a part of the normal islet immune population in mouse and human islets, and accumulate in islets during ageing in a body weight-independent manner. Though comprising only a small subset of the immune cells within islets, islet T cells may play a role in the physiology of islet ageing.

6.
Knee Surg Sports Traumatol Arthrosc ; 27(5): 1635-1641, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30415388

RESUMO

PURPOSE: Knee alignment is a fundamental measurement in the assessment, monitoring and surgical management of patients with osteoarthritis. There is a lack of data regarding how static tibiofemoral alignment varies between supine and standing conditions. This study aimed to quantify the relationship between supine and standing lower limb alignment in asymptomatic, osteoarthritic (OA) and prosthetic (TKA) knees. METHODS: A non-invasive position capture system was used to assess knee alignment for 30 asymptomatic controls and 31 patients with OA both before and after TKA. Coronal and sagittal mechanical femorotibial angles were measured supine with the lower limb in extension and in bipedal stance. Changes between conditions were analysed using paired ttests. Vector plots of ankle centre displacement relative to the knee centre from supine to standing were produced to allow three-dimensional visualisation. RESULTS: All groups showed a trend towards varus and extension when going from supine to standing. Mean change for asymptomatic knees was 1.2° more varus (p = 0.001) and 3.8° more extended (p < 0.001). For OA knees this was 1.1° more varus (p = 0.009) and 5.9° more extended (p < 0.001) and TKA knees 1.9° more varus (p < 0.001) and 5.6° more extended (p < 0.001). CONCLUSION: The observed consistent changes in lower limb alignment between supine and standing positions across knee types suggests the soft tissue envelope restraining the knee may have a greater influence on dynamic alignment changes than the underlying bony deformity. This highlights the importance of quantifying soft tissue behaviour when planning, performing and evaluating alignment dependent surgical interventions of the knee. When routinely assessing any type of knee, clinicians should be aware that subtle consistent alignment changes occur under weightbearing conditions and tailor their treatments accordingly. LEVEL OF EVIDENCE: II.


Assuntos
Articulação do Joelho/cirurgia , Prótese do Joelho , Osteoartrite do Joelho/cirurgia , Postura , Caminhada , Suporte de Carga , Adulto , Idoso , Idoso de 80 Anos ou mais , Articulação do Tornozelo/cirurgia , Artroplastia do Joelho , Estudos de Casos e Controles , Feminino , Humanos , Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
7.
Ann Pharmacother ; 52(5): 425-430, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29319327

RESUMO

BACKGROUND: The absorption of drugs and fat-soluble vitamins is impaired after bariatric surgery on which intestinal length and function are altered. In this context, the anticoagulant effect of warfarin is difficult to predict in the postoperative period. OBJECTIVE: This study aimed at describing the average weekly warfarin dose required to maintain a therapeutic international normalized ratio (INR) before and up to 1 year after sleeve gastrectomy with biliopancreatic diversion and duodenal switch (BPD/DS). Secondary end points included the number of patients requiring a minimal 20% reduction in their weekly dose of warfarin following the BPD/DS. METHODS: This descriptive and retrospective longitudinal population study included 20 patients using warfarin who underwent BPD/DS. An INR was considered nontherapeutic if it was below or above 15% of the targeted therapeutic range for any given patient. RESULTS: One month after the surgery, the median weekly dose of warfarin was 55% lower than the preoperative dose ( P < 0.0001). In the 9 patients with full follow-up data, the warfarin dose at 1 year was still 39% lower than the preoperative dose ( P < 0.05). At that time, all patients presented a minimal dose reduction of 20%. CONCLUSIONS: BPD/DS robustly reduced the requirement of warfarin, which resulted in lower doses after surgery. This persisted over the first year after the surgery, likely because of enhanced sensitivity. The mechanisms for this effect remain multifactorial, and the exact extent of change in dose cannot be predicted.


Assuntos
Anticoagulantes/administração & dosagem , Cirurgia Bariátrica , Desvio Biliopancreático , Gastrectomia , Varfarina/administração & dosagem , Adulto , Feminino , Humanos , Coeficiente Internacional Normatizado , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/cirurgia , Estudos Retrospectivos
8.
Ann Plast Surg ; 81(2): 170-175, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29762444

RESUMO

BACKGROUND: After conventional treatments, keloid scars show varying degrees of recurrence. The aim of this study was to assess the efficacy and safety of platelet-rich plasma in the treatment of postoperative keloid scars refractory to conventional treatments. METHODS: This pilot prospective study was conducted in 17 patients with keloid scars who did not respond to 4 injections of cortisone or radiotherapy after extralesional resection of keloid. Platelet-rich plasma was injected intraoperatively and then 3 times with a 1-month interval. The primary end point was the complete remission of keloid scars 2 years posttreatment. Scar pruritus severity was scored before and after treatment. The study protocol was approved by the ethics committee and authorized by the French National Agency. This trial was registered at ClinicalTrials.gov, identifier NCT02922972. RESULTS: Nine keloid scars (53%) were completely resolved at 2 years, and 5 (29%) completely relapsed after treatment. Pruritus severity score was significantly lower at 2 years compared with baseline (1.33 ± 0.97 before treatment and 0.40 ± 0.63 at 2 years, P < 0.003). The mean Vancouver Scar Scale score significantly improved (8.18 ± 2.38 before treatment and 3.82 ± 1.98 at 2 years, P < 0.001). CONCLUSIONS: Injecting platelet-rich plasma is an effective and safe method as adjunctive therapy to resection for treating keloid scars refractory to conventional therapy.


Assuntos
Transfusão de Sangue Autóloga/métodos , Queloide/terapia , Transfusão de Plaquetas/métodos , Plasma Rico em Plaquetas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Seguimentos , Humanos , Queloide/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
9.
J Arthroplasty ; 33(6): 1861-1867, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29506934

RESUMO

BACKGROUND: Surgical site infection (SSI) is a debilitating complication of lower limb arthroplasty with significant morbidity and increased costs. Numerous risk factors are associated with SSI. METHODS: In an effort to identify novel risk factors for SSI, we undertook a retrospective cohort study of 1832 primary total hip arthroplasties and 2100 primary total knee arthroplasties performed in our high volume arthroplasty unit over a 2-year period. RESULTS: Two risk factors were identified for SSI following total hip arthroplasty: body mass index ≥30 and peri-operative blood transfusion. Eight risk factors were identified for SSI following total knee arthroplasty: hypertension, peri-operative blood transfusion, skin closure using 2-octyl cyanoacrylate, use of oral steroids, reduced serum mean cell volume, reduced mean cell hemoglobin, elevated serum neutrophil count, and use of warfarin or rivaroxaban for venous thromboembolism prophylaxis. CONCLUSIONS: Our work proposes a number of previously undocumented risk factors in relation to SSI. Further investigation is required to ascertain the magnitude of their effect.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue , Índice de Massa Corporal , Cianoacrilatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Estudos Retrospectivos , Fatores de Risco , Rivaroxabana/administração & dosagem , Esteroides/administração & dosagem , Tromboembolia Venosa/prevenção & controle , Varfarina/administração & dosagem , Adulto Jovem
10.
Clin Anat ; 31(7): 981-987, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30203862

RESUMO

The anterior pelvic plane (APP) is a useful anatomical reference with both clinical and research applications in orthopedic surgery and rehabilitation medicine. It is used as a marker for computer-assisted total hip replacement and image-guided assessment of the hip center in clinical gait analysis. Despite its common use, no published data exist on the variations in height and width in an adult population. The aim of this study was to determine the range of dimensions for the anterior pelvic plane found in the Scottish adult population. Thirty-five human cadavers and 100 pelvic computed tomography (CT) scans were examined. Pelvic height and width were measured, and the ratios were determined. The mean width and height for combined cadaver and CT pelves were found to be 238.0 mm (SD 20.1, range 188.3-273.8) and 92.7 mm (SD 10.5, range 71.2-114.7), respectively. The mean width-to-height ratio for all pelves was 2.59 (SD 0.31, range 1.73-3.50). There were no statistically significant differences in means between males and females. The variations of APP dimensions within an adult population are presented. These will be of value in the validation of algorithms for computer navigation and hip joint center calculation in total hip arthroplasty and gait analysis. Furthermore, differences in dimensions between cadaveric and CT measurements have been shown which may have implications for further research and the validity of reference data dependent on data-point acquisition. Clin. Anat. 31:981-987, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Ossos Pélvicos/anatomia & histologia , Pelve/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Articulação do Quadril/anatomia & histologia , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto Jovem
11.
Scott Med J ; 63(4): 132-139, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30153761

RESUMO

INTRODUCTION: The Clostridia species are responsible for life-threatening conditions such as tetanus, botulism and gas gangrene. Clostridium septicum is a rare cause of clinical infection, accounting for less than 1% of blood culture samples that test positive for Clostridia. However, C. septicum bacteraemia is associated with greater than 60% mortality and in over 80% of cases is associated with an underlying malignancy. CASE PRESENTATION: We present a review of the literature and the first case of an acute arthroplasty infection and concurrent infective aortitis caused by this organism in the absence of an identified underlying malignancy. Early diagnosis and multi-disciplinary input resulted in the patient surviving a rare and potentially fatal infective aortitis and septic arthritis. CONCLUSION: This case demonstrates the importance of early systemic investigation to exclude occult infective aortitis in C. septicum infection. The key role of multi-disciplinary input into the management of this often fatal infection is also discussed along with the requirement to exclude occult gastrointestinal and haematological malignancy.

12.
Eur J Orthop Surg Traumatol ; 28(5): 781-791, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29564615

RESUMO

In this review, we outlined the definition of minimally invasive surgery (MIS) in total knee replacement (TKR) and described the different surgical approaches reported in the literature. Afterwards, we went through the most recent studies assessing MIS TKR. Next, we searched for potential limitations of MIS knee replacement and tried to answer the following questions: Are there selective criteria and specific patient selection for MIS knee surgery? If there are, then what are they? After all, a discussion and conclusion completed this article. There is certainly room for MIS or at least less invasive surgery for appropriate selected patients. Nonetheless, there are differences between approaches. Mini-medial parapatellar is easy to master, quick to perform and potentially extendable, whereas mini-subvastus and mini-midvastus are trickier and require more caution related to risk of haematoma and vastus medialis oblique (VMO) nerve damage. Current evidence on the safety and efficacy of mini-incision surgery for TKR does not appear fully adequate for the procedure to be used without special arrangements for consent and for audit or continuing research. There is an argument that a sudden jump from standard TKR to MIS TKR, especially without computer assistance such as navigation, patient-specific instrumentation or robotic, may breach a surgeon's duty of care towards patients because it exposes patients to unnecessary risks. As a final point, more evidence is required on the long-term safety and efficacy of this procedure which will give objective shed light on real benefits of MIS TKR.


Assuntos
Artroplastia do Joelho/métodos , Artropatias/cirurgia , Articulação do Joelho/cirurgia , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos
13.
Mol Pharmacol ; 91(3): 167-177, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049773

RESUMO

Alternative splicing at the human glucuronosyltransferase 1 gene locus (UGT1) produces alternate isoforms UGT1A_i2s that control glucuronidation activity through protein-protein interactions. Here, we hypothesized that UGT1A_i2s function as a complex protein network connecting other metabolic pathways with an influence on cancer cell metabolism. This is based on a pathway enrichment analysis of proteomic data that identified several high-confidence candidate interaction proteins of UGT1A_i2 proteins in human tissues-namely, the rate-limiting enzyme of glycolysis pyruvate kinase (PKM), which plays a critical role in cancer cell metabolism and tumor growth. The partnership of UGT1A_i2 and PKM2 was confirmed by coimmunoprecipitation in the HT115 colon cancer cells and was supported by a partial colocalization of these two proteins. In support of a functional role for this partnership, depletion of UGT1A_i2 proteins in HT115 cells enforced the Warburg effect, with a higher glycolytic rate at the expense of mitochondrial respiration, and led to lactate accumulation. Untargeted metabolomics further revealed a significantly altered cellular content of 58 metabolites, including many intermediates derived from the glycolysis and tricarboxylic acid cycle pathways. These metabolic changes were associated with a greater migration potential. The potential relevance of our observations is supported by the down-regulation of UGT1A_i2 mRNA in colon tumors compared with normal tissues. Alternate UGT1A variants may thus be part of the expanding compendium of metabolic pathways involved in cancer biology directly contributing to the oncogenic phenotype of colon cancer cells. Findings uncover new aspects of UGT functions diverging from their transferase activity.


Assuntos
Processamento Alternativo/genética , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Glucuronosiltransferase/genética , Proteínas de Transporte/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Respiração Celular , Sobrevivência Celular , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Metabolismo Energético , Regulação Neoplásica da Expressão Gênica , Glucuronosiltransferase/metabolismo , Glicólise , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Ácido Láctico/metabolismo , Proteínas de Membrana/metabolismo , Metabolômica , Mitocôndrias/metabolismo , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Hormônios Tireóideos/metabolismo , Proteínas de Ligação a Hormônio da Tireoide
14.
J Arthroplasty ; 32(9): 2783-2787, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28511948

RESUMO

BACKGROUND: Noise after ceramic-on-ceramic (CoC) total hip arthroplasty (THA) is a well-recognized problem. Computer navigation has been shown to achieve desired implant orientation. Our aim was (1) to compare the incidence of noise between navigated and conventional CoC THAs and (2) to determine the factors associated with noise. METHODS: All patients undergoing CoC THA between March 2009 and August 2012 were considered for this study. Information regarding hip noise was obtained via telephone or postal interview. A comparable cohort of patients in navigated and conventional groups was used to evaluate the incidence of noise. RESULTS: A total of 375 CoC THAs using the same implant (202 navigated and 173 conventional) were evaluated. Patients <65 years of age had significantly greater incidence of noise (22.4% vs 6.1%; P < .001). To ensure similarity, a subgroup of cohort <65 years and a 32-mm head size was used to compare the incidence of noise between the navigated (68 THAs) and conventional (118 THAs) groups. Overall incidence of noise was significantly greater in the conventional group (28%) as compared with the navigated group (10%; P = .005). The relative risk of noise for the conventional vs the navigated group was 2.7 (P = .01), and for squeaking was 1.9 (P = .2). Squeaking THAs had significantly lower cup anteversion (13.4° ± 5.2°) as compared with the silent THAs (17.6° ± 6.9°; P = .01). CONCLUSION: Navigated CoC THAs were 2.7× less likely to have noise as compared with the conventional ones. Squeaking THAs had significantly lower cup anteversion as compared with the silent ones. Patients of age <65 years had significantly greater incidence of noise after CoC THA.


Assuntos
Artroplastia de Quadril , Cerâmica , Diagnóstico por Computador , Prótese de Quadril , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Incidência , Masculino , Pessoa de Meia-Idade , Ruído , Estudos Prospectivos , Software , Interface Usuário-Computador
15.
Knee Surg Sports Traumatol Arthrosc ; 24(11): 3575-3583, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27714437

RESUMO

PURPOSE: The aim of this study was to assess the kinematics of arthritic knees prior to TKA. The hypothesis was that the arthritic knee follows distinct patterns with regard to deformity in coronal plane as it flexes from extended position. METHOD: Data from 585 consecutive arthritic knees that had undergone TKA using two non-image-based navigation systems were included in the study. Coronal plane alignment given by the femoro-tibial mechanical angle (FTMA) was recorded in extension, 30°, 60°, 90° and maximum flexion prior to making any bony cuts or ligamentous releases. RESULTS: Complete data were available for 512 (87.5 %) of arthritic knees. It was found that pre-implant arthritic knees behaved in different distinct patterns from full extension to 90° flexion. These patterns in FTMA from extension through to 90° of flexion were classified into 4 major types (1, 2, 3, and 4) and 8 subgroups (1A, 1B, 2A, 2B, 3, 4A, 4B, 4C) for varus and valgus knees. Beyond 90° of flexion, there were no distinct or consistent patterns. There were differences between varus and valgus knee deformities not only in overall numbers (73.8 % varus vs. 21.1 % valgus) but also in kinematic behaviour. Only 14.1 % of total knees had a consistent deformity (Type 1A) which remained the same throughout the range of flexion. 14.1 % knees actually become opposite deformity as the knee flexes; thus, varus becomes valgus and valgus becomes varus as the knee flexes (Type 3 and 4C). CONCLUSION: This study has observed and categorised distinct patterns which arthritic knees follow in the coronal plane as it flexes. This dynamic change during flexion will have bearing on collateral releases that are traditionally done based on deformity in extension or 90° flexion mainly. This may be the underlying cause of flexion instability especially for Types 3 and 4C knees if collateral soft tissue release is done based on deformity in extension. Full significance of this remains unknown and will need further investigation. LEVEL OF EVIDENCE: III.


Assuntos
Geno Valgo/fisiopatologia , Genu Varum/fisiopatologia , Articulação do Joelho/fisiopatologia , Osteoartrite do Joelho/fisiopatologia , Amplitude de Movimento Articular , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/métodos , Fenômenos Biomecânicos , Feminino , Geno Valgo/etiologia , Genu Varum/etiologia , Humanos , Joelho , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia , Cirurgia Assistida por Computador/métodos , Tíbia/cirurgia
16.
Knee Surg Sports Traumatol Arthrosc ; 24(11): 3565-3574, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27704159

RESUMO

PURPOSE: Computer-assisted surgery in orthopaedics is passing through the initial adapter phase of technology adoption. It started more than 20 years ago, but the uptake of technology is still not widespread. The purpose of this article is to introduce the reader to the basic technology and familiarize with the terminology used in the computer navigation. METHODS: During this time, the technology has matured and we have the evidence to prove its benefits for patients. Not only does it help placing the prosthetic components in correct orientation, it also helps with other parameters like blood loss and fat embolism reduction. In addition to being a teaching and training tool, it has also opened new areas of research which now question the traditional practices. Since it is not in commonly used, the basic aspects of computer navigation are not very well known. RESULTS: This paper outlines some important definitions and restates the classification of navigation within the spectrum of computer-assisted technologies; it then elaborates on the key principles behind navigation in knee arthroplasty and goes through some of the differences between navigation systems. Finally, it describes in some detail the surgical steps with an image-free knee navigation system. CONCLUSIONS: Computer-assisted navigation is not mainstream yet, but this article should help readers unfamiliar with the technology to understand the basic terms and how it actually works. LEVEL OF EVIDENCE: III.


Assuntos
Artroplastia do Joelho/métodos , Articulação do Joelho/cirurgia , Cirurgia Assistida por Computador/métodos , Humanos , Imageamento Tridimensional , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Procedimentos Ortopédicos , Tomografia Computadorizada por Raios X
17.
Wound Repair Regen ; 23(5): 638-43, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26019054

RESUMO

Nonhealing chronic wounds and exposed tendons, bones and joints are very challenging to cure specially for diabetic patients. Plastic surgeons have a new weapon to enhance wound healing with the use of autologous growth factors. Recently, the process of fabrication of platelet-rich plasma (PRP) has been simplified. The goal of this literature review is to summarize the evidenced-based body of knowledge regarding the treatment of diabetic chronic wounds by PRP. A PubMed and Cochrane search (1978-2015) was performed and all studies assessing the clinical effect of PRP on the healing of diabetic chronic wounds were included. The screening retrieved 7,555 articles and 12 studies were included. On six randomized studies included, five found significant benefits for the use of PRP on diabetic chronic foot ulcers and the sixth randomized study did not publish a statistical analysis but found favorable outcomes. The two other controlled studies included found significant benefits regarding the healing rate and the four uncontrolled studies included showed high rates of healing with the adjunction of PRP. Regarding the method of use, PRP was applied on the wound as a gel twice a week (41.7% of studies) or once a week (33.3% of studies). In conclusion, 87.5% of controlled studies found a significant benefit for the adjunction of PRP to treat chronic diabetic wounds. As PRP may be beneficial, we suggest using PRP on diabetic ulcers which remain unhealed after standard treatment.


Assuntos
Pé Diabético/terapia , Plasma Rico em Plaquetas , Medicina Regenerativa/normas , Cicatrização , Doença Crônica , Humanos
18.
Wound Repair Regen ; 23(2): 163-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25683096

RESUMO

Platelet-rich plasma seems to help wound healing. The goal of this review is to determine if the adjunction of platelet-rich plasma enhances the clinical outcome of acute wounds, burns, and laser therapies. A PubMed and Cochrane library search was performed by two reviewers with the senior author as a consultant. Medical Subject Headings search terms used were the following: ["Platelet-rich plasma" OR "Platelet gel" OR "Platelet growth factor"] AND ["Acute wound" OR "Wound" OR "Burn" OR "Laser"]. We included controlled studies assessing the clinical outcome of acute wounds, burns, and laser therapies treated by platelet-rich plasma. Nine randomized controlled studies, six prospective controlled studies, and two retrospective controlled studies were included. Regarding acute wounds, three randomized controlled trials found a statistical benefit regarding either the healing time, the return back to work time, the quality of life, or the pain and three prospective controlled studies found a statistical difference regarding the velocity of healing. Platelet-rich plasma decreased the intensity or duration of erythema after laser therapy in four randomized studies. Regarding the long-term outcome of laser therapies, two studies found a statistical benefit and two others did not. Platelet-rich plasma accelerates acute wound healing and decreases erythema after laser therapies. Its use on burns has not been enough studied.


Assuntos
Queimaduras/terapia , Terapia a Laser/métodos , Transfusão de Plaquetas , Plasma Rico em Plaquetas , Úlcera por Pressão/terapia , Úlcera Varicosa/terapia , Cicatrização , Transfusão de Sangue Autóloga , Queimaduras/patologia , Lista de Checagem , Humanos , Úlcera por Pressão/patologia , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Qualidade de Vida , Resultado do Tratamento , Úlcera Varicosa/patologia
19.
Clin Orthop Relat Res ; 473(1): 206-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25002214

RESUMO

BACKGROUND: Surgical robotics has been shown to improve the accuracy of bone preparation and soft tissue balance in unicondylar knee arthroplasty (UKA). However, although extensive data have emerged with regard to a CT scan-based haptically constrained robotic arm, little is known about the accuracy of a newer alternative, an imageless robotic system. QUESTIONS/PURPOSES: We assessed the accuracy of a novel imageless semiautonomous freehand robotic sculpting system in performing bone resection and preparation in UKA using cadaveric specimens. METHODS: In this controlled study, we compared the planned and final implant placement in 25 cadaveric specimens undergoing UKA using the new tool. A quantitative analysis was performed to determine the translational, angular, and rotational differences between the planned and achieved positions of the implants. RESULTS: The femoral implant rotational mean error was 1.04° to 1.88° and mean translational error was 0.72 to 1.29 mm across the three planes. The tibial implant rotational mean error was 1.48° to 1.98° and the mean translational error was 0.79 to 1.27 mm across the three planes. CONCLUSIONS: The image-free robotic sculpting tool achieved accurate implementation of the surgical plan with small errors in implant placement. The next step will be to determine whether accurate implant placement translates into a clinical and functional benefit for the patient.


Assuntos
Artroplastia do Joelho/instrumentação , Fêmur/cirurgia , Articulação do Joelho/cirurgia , Robótica/instrumentação , Cirurgia Assistida por Computador/instrumentação , Tíbia/cirurgia , Pontos de Referência Anatômicos , Artroplastia do Joelho/métodos , Fenômenos Biomecânicos , Cadáver , Desenho de Equipamento , Fêmur/anatomia & histologia , Fêmur/fisiologia , Humanos , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Prótese do Joelho , Teste de Materiais , Cirurgia Assistida por Computador/métodos , Tíbia/anatomia & histologia , Tíbia/fisiologia
20.
J Arthroplasty ; 30(4): 695-700, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25702592

RESUMO

Weight-bearing hip-knee-ankle (HKA) radiographs are the gold standard for measuring lower limb alignment after total knee arthroplasty (TKA), however the majority of UK units use standardised anteroposterior (AP) knee radiographs. This study aimed to determine whether standardised AP knee radiographs adequately assess lower limb alignment after TKA. HKA radiographs from 50 post-operative TKAs were cropped to the size of a standardised AP knee radiograph allowing comparison of mechanical and anatomical alignment measurements between the two views. Repeatability of alignment measurements was significantly better for HKA radiographs, however, there was poor agreement of the mechanical alignment measured between the two views. Standardised AP knee radiographs are insufficient to assess the mechanical alignment of post-operative TKA and we recommend routinely using HKA radiographs.


Assuntos
Artroplastia do Joelho , Mau Alinhamento Ósseo/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Articulação do Joelho/cirurgia , Período Pós-Operatório , Radiografia , Estudos Retrospectivos , Suporte de Carga
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