Effects of Contextual Variables on Match Load in a Professional Soccer Team Attending to the Different Season Periods.

This study aimed to analyze the effects of contextual variables (i.e., match location and match outcome) and season periods on match load (i.e., internal and external load) in professional Brazilian soccer players. Thirty-six professional players from the same soccer team participated in this study. The season was split into four phases: matches 1-16 (i.e., Phase 1 = P1); matches 17-32 (i.e., Phase 2 = P2); matches 33-48, (i.e., Phase 3 = P3); matches 49-65 (i.e., Phase 4 = P4). Considering match outcome, when the team wins, Cognitive load, Emotional load, and Affective load were significantly higher in away vs. home matches (p < 0.05). Considering season phases, in P3, Mental Fatigue was significantly higher in drawing than in losing matches (p < 0.05). Additionally, considering the match outcome, when the team lost, Total Distance (TD)/min and TD > 19 km·h-1/min were significantly lower in P1 than P2 (p < 0.001), P3 (p < 0.001), and P4 (p < 0.001). These results suggest to strength and conditioning coaches the need to consider the outcome and location of the previous game when planning the week, as well as the phase of the season they are in to reduce fatigue and injury risk.

The dynamin Vps1 mediates Atg9 transport to the sites of autophagosome formation.

Autophagy is a key process in eukaryotes to maintain cellular homeostasis by delivering cellular components to lysosomes/vacuoles for degradation and reuse of the resulting metabolites. Membrane rearrangements and trafficking events are mediated by the core machinery of autophagy-related (Atg) proteins, which carry out a variety of functions. How Atg9, a lipid scramblase and the only conserved transmembrane protein within this core Atg machinery, is trafficked during autophagy remained largely unclear. Here, we addressed this question in yeast Saccharomyces cerevisiae and found that retromer complex and dynamin Vps1 mutants alter Atg9 subcellular distribution and severely impair the autophagic flux by affecting two separate autophagy steps. We provide evidence that Vps1 interacts with Atg9 at Atg9 reservoirs. In the absence of Vps1, Atg9 fails to reach the sites of autophagosome formation, and this results in an autophagy defect. The function of Vps1 in autophagy requires its GTPase activity. Moreover, Vps1 point mutants associated with human diseases such as microcytic anemia and Charcot-Marie-Tooth are unable to sustain autophagy and affect Atg9 trafficking. Together, our data provide novel insights on the role of dynamins in Atg9 trafficking and suggest that a defect in this autophagy step could contribute to severe human pathologies.

The American College of Surgeons National Surgical Quality Improvement Program surgical risk calculator is not reliable in predicting complications and length of stay after primary total hip arthroplasty at an institution implementing clinical pathways.

INTRODUCTION: The authors aimed to: (1) determine how length of stay (LOS) and complication rates changed over the past 10 years, in comparison to values estimated by the ACS-NSQIP surgical risk calculator, at a single private institution open to external surgeons; and (2) determine preoperative patient factors associated with complications. METHODS: We retrospectively assessed 1018 consecutive patients who underwent primary elective THA over 10 years. We excluded 87 with tumours and 52 with incomplete records. Clinical data of the remaining 879 were used to determine real LOS and rate of 9 adverse events over time, as well as to estimate these values using the risk calculator. Its predictive reliability was represented on receiver operating characteristic curves. Multivariable analyses were performed to determine associations of complications with age, sex, ASA score, diabetes, hypertension, heart disease, smoking and BMI. RESULTS: Over the 10-year period, real LOS and real complication rates decreased considerably, while LOS and complication rates estimated by the surgical risk calculator had little or no change. The difference between real and estimated LOS decreased over time. The overall estimated and real rates of any complication were respectively 3.3% and 2.8%. The risk calculator had fair reliability for predicting any complications (AUC 0.72). Overall estimated LOS was shorter than the real LOS in 764 (86.9%) patients. Multivariable analysis revealed risks of any complication to be greater in patients aged ⩾75 (OR = 4.36, p = 0.002), and with hypertension (OR = 3.13, p = 0.016). CONCLUSIONS: Since the implementation of clinical pathways at our institution, real LOS and complication rates decreased considerably, while LOS and complication rates estimated by the surgical risk calculator had little or no change. The difference between real and estimated LOS decreased over time, which could lead some clinicians to reconsider their discharge criteria, knowing that advanced age and hypertension increased risks of encountering complications.

Effects of match contextual factors on internal and external load in elite Brazilian professional soccer players through the season.

This study aimed to investigate the effects of contextual match factors (quality of opposition, match outcome, change of head coach or playing style) on internal and external load in elite Brazilian professional soccer players, considering the total and effective playing time. Twenty-two professional male outfield soccer players participated in this study (age 28.4 ± 4.9 years; height 1.78 ± 0.1 cm; body mass 72.9 ± 7.1 kg). The internal (rating of perceived exertion-based load [sRPE]) and external load (distance and accelerometry-based measures) were recorded during 38 matches, over the 2021 season of the Brazilian National 1st Division League using a global position system (10 Hz) integrated with an accelerometer (200 Hz). The main results were: (i) matches played against weak opponents presented greater values of sprinting distances compared to matches against intermediate and strong opponents; (ii) players covered greater high-intensity running distances when drawing than winning the matches; (iii) matches with assistant coaches presented higher mean speed relative to effective playing time (MSEPT) compared to coach 1 and coach 2 conditions. In addition, players covered greater MSEPT and high-acceleration in matches with coach 2 vs. coach 3; (iv) finally, small positive correlations were observed between positional attack sequences and MSTPT, total distance covered, and acceleration. Coaches and practitioners should consider these results when interpreting external load variables during elite Brazilian soccer matches.

TOTAL HIP ARTHROPLASTY IN THE PUBLIC HEALTH SYSTEM OF SÃO PAULO: COMPARING TYPES OF FIXATION.

Brazil lacks registries on the prevalence of primary total hip arthroplasty (THA) fixation methods. Objective: (i) to describe the demographic profile of patients who underwent THA in the public health system of the municipality of São Paulo during the last 12 years and (ii) to compare fixation methods regarding costs, hospital stay length, and death rates. Methods: This is an ecological study conducted with data available on TabNet, a platform belonging to DATASUS. Public data (from the government health system) on THA procedures performed in São Paulo from 2008 to 2019 were extracted. Gender, age, city region, THA fixation method, number of surgeries, costs, hospital stay length, and death rates were analyzed. Results: We analyzed 7,673 THA, of which 6220 (81%) were performed via cementless/hybrid fixation and 1453 (19%), via the cemented technique. Cementless/hybrid fixation had a higher cost (US$ 495.27) than the cemented one (p < 0.001). Nevertheless, hospital stay length was 0.87 days longer for cemented fixation than the cementless/hybrid one. We found no significant difference in death rates between THA fixation methods. Conclusion: THA cementless/hybrid fixation is prevalent in the municipality of São Paulo, which had higher total costs and shorter hospitalizations than cemented fixation. We found no difference between THA fixation methods and death rates. Level of Evidence IV, Case Series.

No Brasil, não há registros da prevalência do tipo de fixação da artroplastia total de quadril (ATQ). Objetivo: (i) Descrever perfil demográfico de pacientes submetidos à ATQ no Sistema Único de Saúde de São Paulo durante os últimos doze anos; e (ii) comparar as técnicas de fixação de ATQ quanto aos custos, tempo de internação (TI) e taxa de óbito. Métodos: Estudo ecológico, com dados disponíveis na TabNet do DATASUS. Dados públicos de procedimentos de ATQ eletivos realizados em São Paulo de 2008 a 2019 foram extraídos. Foram analisados: sexo, idade, região municipal, método de fixação em ATQ, número de cirurgias, custo, tempo de internação e óbitos. Resultados: Foram analisadas 7.673 ATQs, sendo 6.220 (81%) não-cimentada/híbridas e 1.453 (19%) cimentadas. A fixação não-cimentada/híbrida teve custo maior em US$ 495,27 do que a cimentada (p < 0,001). Entretanto, TI foi 0,87 dia mais longo na fixação cimentada. Não houve diferença significativa nas taxas de óbito entre os métodos de fixação. Conclusão: A fixação não-cimentada/híbrida na ATQ é prevalente em São Paulo, e apresentou maior custo total, porém menor tempo de internação do que a fixação cimentada. Não houve diferença entre o método de fixação em ATQ e a taxa de óbito. Nível de Evidência IV, Série de Casos.

Urinary tubular biomarkers as predictors of death in critically ill patients with COVID-19.

Aim: To evaluate the prediction capacity of urinary biomarkers for death in critically ill patients with COVID-19. Methods: This is a prospective study with critically ill patients due to COVID-19 infection. The urinary biomarkers NGAL, KIM-1, MCP-1 and nephrin were quantified on ICU admission. Results: There was 40% of death. Urinary nephrin and MCP-1 had no association with death. Tubular biomarkers (proteinuria, NGAL and KIM-1) were predictors of death and cut-off values of them for death were useful in stratify patients with worse prognosis. In a multivariate cox regression analysis, only NGAL remains associated with a two-mount survival chance. Conclusion: Kidney tubular biomarkers, mostly urinary NGAL, had useful capacity to predict death in critically ill COVID-19 patients.

Total hip arthroplasty in the public health system of são paulo: comparing types of fixation / Artroplastia total de quadril no sistema público de são paulo: comparando os tipos de fixação

ABSTRACT Brazil lacks registries on the prevalence of primary total hip arthroplasty (THA) fixation methods. Objective: (i) to describe the demographic profile of patients who underwent THA in the public health system of the municipality of São Paulo during the last 12 years and (ii) to compare fixation methods regarding costs, hospital stay length, and death rates. Methods: This is an ecological study conducted with data available on TabNet, a platform belonging to DATASUS. Public data (from the government health system) on THA procedures performed in São Paulo from 2008 to 2019 were extracted. Gender, age, city region, THA fixation method, number of surgeries, costs, hospital stay length, and death rates were analyzed. Results: We analyzed 7,673 THA, of which 6220 (81%) were performed via cementless/hybrid fixation and 1453 (19%), via the cemented technique. Cementless/hybrid fixation had a higher cost (US$ 495.27) than the cemented one (p < 0.001). Nevertheless, hospital stay length was 0.87 days longer for cemented fixation than the cementless/hybrid one. We found no significant difference in death rates between THA fixation methods. Conclusion: THA cementless/hybrid fixation is prevalent in the municipality of São Paulo, which had higher total costs and shorter hospitalizations than cemented fixation. We found no difference between THA fixation methods and death rates. Level of Evidence IV, Case Series.

RESUMO No Brasil, não há registros da prevalência do tipo de fixação da artroplastia total de quadril (ATQ). Objetivo: (i) Descrever perfil demográfico de pacientes submetidos à ATQ no Sistema Único de Saúde de São Paulo durante os últimos doze anos; e (ii) comparar as técnicas de fixação de ATQ quanto aos custos, tempo de internação (TI) e taxa de óbito. Métodos: Estudo ecológico, com dados disponíveis na TabNet do DATASUS. Dados públicos de procedimentos de ATQ eletivos realizados em São Paulo de 2008 a 2019 foram extraídos. Foram analisados: sexo, idade, região municipal, método de fixação em ATQ, número de cirurgias, custo, tempo de internação e óbitos. Resultados: Foram analisadas 7.673 ATQs, sendo 6.220 (81%) não-cimentada/híbridas e 1.453 (19%) cimentadas. A fixação não-cimentada/híbrida teve custo maior em US$ 495,27 do que a cimentada (p < 0,001). Entretanto, TI foi 0,87 dia mais longo na fixação cimentada. Não houve diferença significativa nas taxas de óbito entre os métodos de fixação. Conclusão: A fixação não-cimentada/híbrida na ATQ é prevalente em São Paulo, e apresentou maior custo total, porém menor tempo de internação do que a fixação cimentada. Não houve diferença entre o método de fixação em ATQ e a taxa de óbito. Nível de Evidência IV, Série de Casos.

Intraparenchymal subependymoma: Case report and literature review.

BACKGROUND: Intracranial subependymomas are rare slow-growing benign tumors typically located in the ventricular system, accounting for 0.07-0.7% of all intracranial neoplasms. Intraparenchymal subependymoma is extremely rare lesions, imposing a challenging diagnosis and management. CASE DESCRIPTION: We describe a case of a supratentorial intraparenchymal mass on left occipital lobe in a 26-year-old woman with progressive headache and visual impairment. Differential diagnosis mainly included gliomas, neuronal-glial tumors, ependymoma, and subependymoma. Complete surgical resection was performed and histopathology analysis confirmed diagnosis of subependymoma. Despite its benign behavior the Ki67/MIB-1 labeling index assessed by immunohistochemistry was 5%. After 1 year of follow-up she was free of tumor recurrence. CONCLUSION: Intraparenchymal subependymoma is extremely rare tumors and literature review showed only 11 cases reported. In general, they are misdiagnosed as other tumors, so careful attention on clinical and radiological features must be taken when looking at a tumor close to the ventricular system, even though it does not have any obvious direct connection to it. Despite its benign nature, total removal must be attempted given that there are reports of recurrence, especially in partially removed tumors with high proliferation index. The role of adjuvant therapy is still limited and new treatment options are being developed as our knowledge on biological and molecular characteristics advances.

Sodium Bicarbonate Supplementation Does Not Improve Running Anaerobic Sprint Test Performance in Semiprofessional Adolescent Soccer Players.

Ergogenic strategies have been studied to alleviate muscle fatigue and improve sports performance. Sodium bicarbonate (NaHCO3) has improved repeated sprint performance in adult team-sports players, but the effect for adolescents is unknown. The aim of the present study was to evaluate the effect of NaHCO3 supplementation on repeated sprint performance in semiprofessional adolescent soccer players. In a double-blind, placebo-controlled, crossover trial, 15 male semiprofessional adolescent soccer players (15 ± 1 years; body fat 10.7 ± 1.3%) ingested NaHCO3 or a placebo (sodium chloride) 90 min before performing the running anaerobic sprint test (RAST). A countermovement jump was performed before and after the RAST, and ratings of perceived exertion, blood parameters (potential hydrogen and bicarbonate concentration), and fatigue index were also evaluated. Supplementation with NaHCO3 promoted alkalosis, as demonstrated by the increase from the baseline to preexercise, compared with the placebo (potential hydrogen: +0.07 ± 0.01 vs. -0.00 ± 0.01, p < .001 and bicarbonate: +3.44 ± 0.38 vs. -1.45 ± 0.31 mmol/L, p < .001); however, this change did not translate into an improvement in RAST total time (32.12 ± 0.30 vs. 33.31 ± 0.41 s, p = .553); fatigue index (5.44 ± 0.64 vs. 6.28 ± 0.64 W/s, p = .263); ratings of perceived exertion (7.60 ± 0.33 vs. 7.80 ± 0.10 units, p = .525); countermovement jump pre-RAST (32.21 ± 3.35 vs. 32.05 ± 3.51 cm, p = .383); or countermovement jump post-RAST (31.70 ± 0.78 vs. 32.74 ± 1.11 cm, p = .696). Acute NaHCO3 supplementation did not reduce muscle fatigue or improve RAST performance in semiprofessional adolescent soccer players. More work assessing supplementation in this age group is required to increase understanding in the area.

Koh group influence on titanium surfaces and pure sol-gel silica for enhanced osteogenic activity.

Although, the excellent level of success of titanium surfaces is based on the literature, there are some biological challenges such as unfavorable metabolic conditions or regions of poor bone quality where greater surface bioactivity is desired. Seeking better performance, we hypothesized that silica-based coating via sol-gel route with immersion in potassium hydroxide basic solution induces acceleration of bone mineralization. This in vitro experimental study coated titanium surfaces with bioactive glass synthesized by route sol-gel via hydrolysis and condensation of chemical alkoxide precursor, tetraethylorthosilicate (TEOS) and/or deposition of chemical compound potassium hydroxide (KOH) to accelerate bone apposition. The generated surfaces titanium(T), titanium with potassium hydroxide deposition (T + KOH), titanium with bioactive glass deposition synthesized by sol-gel route via tetraethylorthosilicate hydrolysis (TEOS), titanium with bioactive glass deposition synthesized by sol-gel route via tetraethylorthosilicate hydrolysis with potassium hydroxide deposition (TEOS + KOH) were characterized by 3D optical profilometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), contact angle by the sessile drop method, x-ray excited photoelectron spectroscopy (XPS) and energy dispersive x-ray spectrometer (EDX). The addition of the KOH group on the pure titanium (T) or bioactive glass (TEOS) surfaces generated a tendency for better results for mineralization. Groups covered with bioactive glass (TEOS, TEOS + KOH) tended to outperform even groups with titanium substrate (T, T + KOH). The addition of both, bioactive glass and KOH, in a single pure titanium substrate yielded the best results for the mineralization process.

The Direct Anterior Approach for Total Hip Arthroplasty for Severe Dysplasia (Crowe III and IV) Provides Satisfactory Medium to Long-Term Outcomes.

BACKGROUND: The direct anterior approach (DAA) is increasingly used for total hip arthroplasty (THA). Although the DAA can reduce pain, recovery time, and dislocations in nondysplastic hips, few studies report its results in patients with severe dysplasia. We aimed to evaluate outcomes of primary THA through the DAA with cup placement at the true acetabulum in hips with severe dysplasia. METHODS: We retrospectively evaluated 23 consecutive patients (29 hips) who underwent THA by DAA for osteoarthritis secondary to Crowe III-IV dysplasia. Surgical procedures were performed on a traction table, and the acetabular cup was placed in the true acetabulum. Patients were assessed clinically (complications, modified Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, Oxford Hip Score) and radiographically (radiolucencies, subsidence, leg length discrepancies, cup inclination, and cup coverage) at a minimum of 2 years. RESULTS: One patient (2 hips) died with original implants (at 13 and 14 years), 3 patients (3 hips) were revised due to wear-induced loosening (at 14, 16, and 18 years), and there were no dislocations or infections. The remaining 19 patients (24 hips) were assessed at 8.4 ± 4.7 years (range 2-20); 2 patients (2 hips) had complications that required reoperation without implant removal. The modified Harris Hip Score improved from 32 ± 9 to 94 ± 7, Western Ontario and McMaster Universities Osteoarthritis Index from 46 ± 18 to 90 ± 7, and Oxford Hip Score was 56 ± 4. Patients were very satisfied (90%) or satisfied (10%). Limb length discrepancy was 2.5 ± 9.0 mm. CONCLUSION: THA through the DAA with cup placement at the true acetabulum provides satisfactory mid to long-term clinical and radiographic outcomes compared to other approaches for hips with severe dysplasia. LEVEL OF EVIDENCE: Level IV, retrospective cohort study.

Superfícies de titânio modificadas por vidros bioativos e hidróxido de potássio: produção, caracterização das superfícies e avaliação biológica in vitro / Titanium surfaces modified by bioactive glasses and potassium hydroxide: production, surface characterization and in vitro biological evaluation

Apesar do consolidado sucesso dos implantes dentários em condições de normalidade, alguns desafios biológicos requerem uma maior reatividade da superfície de implantes. A osseointegração é um processo decorrente de estímulos físicos, químicos e biológicos de complexa interrelação, que podem ser modificados para uma melhor performance. Buscando melhor desempenho em situações metabólicas desfavoráveis ou regiões de pobre qualidade óssea, é defendido o revestimento da superfície de titânio com materiais mais bioativos a fim de acelerar a fixação e diferenciação celular, e consequente aposição óssea. Esse estudo experimental in vitro teve como objetivo sintetizar, caracterizar e testar a capacidade de osseoindução de novos materiais compostos de vidro bioativo. Para isso, discos de titânio, grau 4, tiveram a superfície tratada por jateamento com óxido de alumínio e duplo ataque ácido (HNO3/HF) (grupo I ­ "T"). As superfícies tratadas do titânio foram revestidas pelo processo de imersão controlada em dip-coating com dois novos materiais à base de vidro bioativo sintetizados pela rota solgel em baixas temperaturas (grupos III, IV e V ­ "TEOS, TEOS+KOH, BIOV", respectivamente). Por fim, dois grupos receberam uma imersão de solução básica de KOH (grupos II e IV ­ "T+KOH, TEOS+KOH"). Os métodos de caracterização topográfica foram executados por técnicas de análise de rugosidade (Sa e RMS) pelo perfilômetro óptico 3D e microscopia eletrônica de varredura (MEV); análise de hidrofilicidade pelo método de gota séssil; e mensuração da espessura do revestimento pelo microscópio eletrônico de transmissão (MET). As caracterizações químicas foram realizadas por meio de MEV+ espectrômetro de raio X por dispersão de energia (EDS); MET+EDS; e espectroscopia de fotoelétrons excitado por raios x (XPS). Análises biológicas in vitro utilizando células pré-osteoblásticas imortalizadas da calvária de camundongos neonatos MC3T3 foram realizadas por ensaios de viabilidade celular (MTT ­ 24 horas e 7 dias); ensaio de mineralização (alizarina ­ 21 dias); e avaliação de morfologia celular por imagens de MEV+EDS (7 e 14 dias). O efeito dos fatores em estudo, na rugosidade e hidrofilicidade da superfície, foi verificado por ANOVA e teste post-hoc de Tukey (p≤0,05). Não houve diferença estatisticamente significativa entre os grupos na avaliação da rugosidade aritmética (Sa) e da rugosidade quadrática média (RMS). Os resultados dos testes de hidrofilicidade de superfície mostraram maior molhabilidade para a superfície de vidro bioativo do grupo BIOV (P<0,05). Os ensaio de MTT em 24 horas e 7 dias não apresentaram diferenças estatisticamente significativas entre os grupos. Os grupos TEOS+KOH e BIOV obtiveram os melhores resultados para o ensaio de mineralização após 21 dias de cultura celular. Conclui-se que as superfícies testadas apresentaram-se viáveis e não citotóxicas para o crescimento de células osteoblásticas MC3T3. Os quatro grupos testados, T+KOH, TEOS, TEOS+KOH e BIOV apresentaram respostas biológicas positivas de mineralização, crescimento e multiplicação celular. Os revestimentos de vidro bioativo, independentemente da via de síntese, apresentaram resultados significativamente melhores do que as superfícies de titânio sem revestimento de vidro bioativo.

Despite the consolidated success of dental implants under normal conditions, some biological challenges require a higher reactivity of the implant surface. Osseointegration is a process due to physical, chemical and biological stimuli of complex interrelationships, which can be modified for better performance. Seeking better performance in unfavorable metabolic situations or regions of poor bone quality, the coating of the titanium surface with more bioactive materials is advocated in order to accelerate cell attachment and differentiation, and consequent bone apposition. This in vitro experimental study aimed to synthesize, characterize and test the osseoinduction capacity of new bioactive glass composite materials. For this, titanium discs, grade 4, had the surface treated by blasting with aluminum oxide and double acid attack (HNO3 / HF) (group I - "T"). The treated surfaces of the titanium were coated by the dip-coating controlled immersion process with two new bioactive glass-based materials synthesized by the route solgel at low temperatures (groups III, IV and V - TEOS, TEOS + KOH, BIOV, respectively). Finally, two groups received an immersion of basic KOH solution (groups II and IV - "T + KOH, TEOS + KOH"). The topographic characterization methods were performed by roughness analysis techniques (Sa and RMS) by 3D optical profilometer and scanning electron microscopy (SEM); hydrophilicity analysis by sessile droplet method; and thickness measurement of the coating by the transmission electron microscope (MET). The chemical characterization was performed by MEV + energy dispersive X-ray spectrometer (EDS); MET + EDS; and x-ray excited photoelectron spectroscopy (XPS). In vitro biological analyzes using immortalized pre-osteoblastic calvarial cells from MC3T3 neonates were performed by cell viability assays (MTT - 24 hours and 7 days); mineralization test (alizarin - 21 days); and evaluation of cell morphology by SEM and EDS images (7 and 14 days). The effect of the factors under study, surface roughness and hydrophilicity was verified by ANOVA and Tukey post-hoc test (p≤0.05). There was no statistically significant difference between the groups in the evaluation of arithmetic roughness (Sa) and mean square roughness (RMS). The results of the surface hydrophilicity tests showed greater wettability for the bioactive glass surface of the BIOV group (P <0.05). The 24- hour and 7-day MTT assay did not show statistically significant differences between the groups. The TEOS + KOH and BIOV groups obtained the best results for the mineralization assay after 21 days of cell culture. It is concluded that the surfaces tested were viable and non-cytotoxic for growth of MC3T3 osteoblastic cells. The four groups tested, T + KOH, TEOS, TEOS + KOH and BIOV presented positive biological responses of mineralization, growth and cell multiplication. Bioactive glass coatings, regardless of the synthetic pathway, showed significantly better results than uncoated titanium surfaces of bioactive glass.

Comparative Study of the Osteointegration of Irradiated and Non-irradiated Bone Grafts Used in Patients with Revision Hip Arthroplasty.

Objective To evaluate and compare the osteointegration of irradiated and non-irradiated frozen bone grafts used in 21 patients undergoing revision hip arthroplasty procedures with the Exeter technique. Methods A retrospective study of 21 patients undergoing revision hip arthroplasty with the Exeter technique using bone tissues treated or not with gamma radiation between 2013 and 2014. The patients were divided into two groups according to the use of grafts treated or not with ionizing radiation (gamma rays); as such, these groups were classified as irradiated or non-irradiated. The osteointegration results determined by radiographic analysis of these grafts were compared in the postoperative period of 6 and 12 months. Results Comparing the graft osteointegration in all patients at 6 and 12 months postoperatively, we noticed a significant difference in the radiographic evaluations in this period ( p = 0.031). Out of the patients studied, 7 were from the irradiated group, and 14 belonged to the non-irradiated group. No statistically significant differences were observed ( p = 0.804) regarding osteointegration when we compared the irradiated and non-irradiated groups. Conclusion There was no significant difference in the use of irradiated or non-irradiated grafts in revision hip arthroplasty procedures with the Exeter technique.

Comparative Study of the Osteointegration of Irradiated and Non-irradiated Bone Grafts Used in Patients with Revision Hip Arthroplasty / Estudo comparativo da osteointegração de enxertos ósseos irradiados e não irradiados utilizados em pacientes com revisão de artroplastia do quadril

Abstract Objective To evaluate and compare the osteointegration of irradiated and nonirradiated frozen bone grafts used in 21 patients undergoing revision hip arthroplasty procedures with the Exeter technique. Methods A retrospective study of 21 patients undergoing revision hip arthroplasty with the Exeter technique using bone tissues treated or not with gamma radiation between 2013 and 2014. The patients were divided into two groups according to the use of grafts treated or not with ionizing radiation (gamma rays); as such, these groups were classified as irradiated or non-irradiated. The osteointegration results determined by radiographic analysis of these grafts were compared in the postoperative period of 6 and 12months. Results Comparing the graft osteointegration in all patients at 6 and 12months postoperatively, we noticed a significant difference in the radiographic evaluations in this period (p = 0.031). Out of the patients studied, 7 were from the irradiated group, and 14 belonged to the non-irradiated group. No statistically significant differences were observed (p = 0.804) regarding osteointegration when we compared the irradiated and non-irradiated groups. Conclusion There was no significant difference in the use of irradiated or nonirradiated grafts in revision hip arthroplasty procedures with the Exeter technique.

Resumo Objetivo Avaliar e comparar a osteointegração dos enxertos ósseos congelados irradiados e não irradiados utilizados em 21 pacientes submetidos a revisão de prótese do quadril pela técnica Exeter. Métodos Foi realizado estudo retrospectivo de 21 pacientes submetidos a revisão de artroplastia do quadril pela técnica Exeter comutilização de tecidos ósseos tratados ou não com radiação gama no período entre 2013 e 2014. Dividimos os pacientes em dois grupos, de acordo com o uso do enxerto tratado ou não com radiação ionizante (raios gama), que foram, portanto, classificados como: grupo irradiado e não irradiado. Os resultados da osteointegração por análise radiográfica destes enxertos foram comparados no pós-cirúrgico de 6 e 12 meses. Resultados Quando comparamos a osteointegração dos enxertos no pós-cirúrgico de 6 e 12 meses de todos os pacientes, notamos que houve diferença significativa entre as avaliações radiográficas neste período (p= 0,031). Dos pacientes estudados, 7 pertenciam ao grupo irradiado, e 14, ao grupo não irradiado. Não foram observadas diferenças estatisticamente significativas (p= 0,804) quando a osteointegração entre os grupos irradiados e não irradiados foi comparada. Conclusão Não houve diferença significativa no uso de enxerto irradiado e não irradiado nas revisões de artroplastias do quadril pela técnica Exeter.

Analysis of potential contamination factors in musculoskeletal tissues.

Tissue Banks have become the main source for bone grafts, due to preference for homologous tissues. Notwithstanding the use of aseptic techniques for procurement of tissues and judicious selection of donors, microorganisms are frequently found in procured bones. Purpose of this study is to evaluate the factors that increase safety of procurement and minimize discard of procured tissues. Microbiological contamination was analyzed in 1271 musculoskeletal tissues removed from 138 multi-organ donors over a period extending from 2006 to 2016. Effects of various risk factors related with contamination were estimated using a logistic regression model. Microbiological contamination rate in the tissues was 17.1%; low pathogenic microorganisms were cultivated in 12.9% of the tissues, while highly pathogenic ones were cultivated in 4.2% of the tissues. Evolution of one single team was monitored during that period, verifying a fall in the general contamination level from 22.5 to 9.2%. Absence of antibiotics increased low pathogenic contamination risk. Every additional day in intensive care unit (ICU) increased the risk of highly pathogenic contamination. Time elapsed between death and the beginning of removal procedures was found to be relevant for both low pathogenic and highly pathogenic microorganisms. Among the studied factors, the following contributed for a significant increase in contamination by microorganisms in removed tissues: lack of use of prophylactic antibiotic therapy in donors, quantity of removed tissues, length of admission in ICU and the time elapsed between aortic clamping and beginning of the removal procedure.

Atg9 establishes Atg2-dependent contact sites between the endoplasmic reticulum and phagophores.

The autophagy-related (Atg) proteins play a key role in the formation of autophagosomes, the hallmark of autophagy. The function of the cluster composed by Atg2, Atg18, and transmembrane Atg9 is completely unknown despite their importance in autophagy. In this study, we provide insights into the molecular role of these proteins by identifying and characterizing Atg2 point mutants impaired in Atg9 binding. We show that Atg2 associates to autophagosomal membranes through lipid binding and independently from Atg9. Its interaction with Atg9, however, is key for Atg2 confinement to the growing phagophore extremities and subsequent association of Atg18. Assembly of the Atg9-Atg2-Atg18 complex is important to establish phagophore-endoplasmic reticulum (ER) contact sites. In turn, disruption of the Atg2-Atg9 interaction leads to an aberrant topological distribution of both Atg2 and ER contact sites on forming phagophores, which severely impairs autophagy. Altogether, our data shed light in the interrelationship between Atg9, Atg2, and Atg18 and highlight the possible functional relevance of the phagophore-ER contact sites in phagophore expansion.

Conserved Atg8 recognition sites mediate Atg4 association with autophagosomal membranes and Atg8 deconjugation.

Deconjugation of the Atg8/LC3 protein family members from phosphatidylethanolamine (PE) by Atg4 proteases is essential for autophagy progression, but how this event is regulated remains to be understood. Here, we show that yeast Atg4 is recruited onto autophagosomal membranes by direct binding to Atg8 via two evolutionarily conserved Atg8 recognition sites, a classical LC3-interacting region (LIR) at the C-terminus of the protein and a novel motif at the N-terminus. Although both sites are important for Atg4-Atg8 interaction in vivo, only the new N-terminal motif, close to the catalytic center, plays a key role in Atg4 recruitment to autophagosomal membranes and specific Atg8 deconjugation. We thus propose a model where Atg4 activity on autophagosomal membranes depends on the cooperative action of at least two sites within Atg4, in which one functions as a constitutive Atg8 binding module, while the other has a preference toward PE-bound Atg8.

Is the size of the acetabular bone lesion a predictive factor for failure in revisions of total hip arthroplasty using an impacted allograft?

OBJECTIVE: The aim of this study was to determine the acetabular bone lesion size (in millimeters) from which impacted bone graft failure starts to occur more frequently, through simple anteroposterior hip radiographs, and whether measurement of the defect on simple radiographs maintains the same pattern in inter and intraobserver assessments. METHODS: Thirty-eight anteroposterior pelvic-view radiographs from patients undergoing revision of an acetabular prosthesis were retrospectively analyzed and assessed. In the vertical plane, the bilacrimal line was measured in millimeters from the farthest point found on the bone edge of the acetabular osteolysis to the top edge of the cementation or of the acetabular implant in uncemented cases. The base was taken to be a line perpendicular to bilacrimal line, with the aim of eliminating any pelvic tilt effects. This measurement was named the vertical size of failure. Radiographs produced four years after the operation were analyzed to investigate any failure of the technique. RESULTS: The graft failure rate in the study group was 26.3%. The failures occurred in cases with an initial bone defect larger than 11 mm. No cases with measurements smaller than this evolved with failure of the revision. The highest incidence of graft failure occurred in cases described as advanced according to the "Paprosky" classification. CONCLUSION: Failure of acetabular revision arthroplasty using an impacted graft did not present any statistically significant correlation with the vertical extent of the lesion on simple anteroposterior radiographs, as a predictor of treatment failure.

OBJETIVO: O presente trabalho buscou, através de uma radiografia simples anteroposterior do quadril, quantificar em milímetros a partir de qual tamanho da lesão óssea acetabular ocorre com maior frequência falha do enxerto ósseo impactado e se a medição do defeito nas radiografias simples mantém o mesmo padrão na avaliação inter e intraobservador. MÉTODOS: Foram analisadas e aferidas retrospectivamente 38 radiografias de pacientes submetidos à revisão de prótese acetabular na incidência anteroposterior de bacia, mensurando em milímetros, no plano vertical a linha bilacrimal, a medida entre o ponto mais distante encontrado na borda óssea da osteolise acetabular, com a margem superior da cimentação ou implante acetabular nos casos não cimentados. Tomamos como base uma linha perpendicular a linha bilacrimal com o intuito de eliminar efeitos de inclinação pelvic. Essa medida foi denominada Tamanho Vertical da Falha. Radiografias pós-operatórias com quatro anos foram analisadas para averiguar falha da técnica. RESULTADOS: No grupo estudado observamos 26,3% de falhas do enxerto que ocorreram a partir de 11 mm de tamanho da falha óssea inicial mensurada e que abaixo desse valor nenhum caso evoluiu com falha da revisão. A maior incidência da falha do enxerto ocorreu nos casos avançados segundo a classificação de Paprosky. CONCLUSÃO: A falha na artroplastia de revisão acetabular com enxerto impactado quando relacionado à medida vertical da lesão em radiografia simples anteroposterior do quadril não apresentou significância estatística como fator preditivo de falha do tratamento.