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1.
J Biol Chem ; 299(5): 104712, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37060997

RESUMO

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.


Assuntos
Autofagossomos , Proteínas de Saccharomyces cerevisiae , Humanos , Autofagossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Dinaminas/metabolismo , Vacúolos/metabolismo , Autofagia , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Transporte Proteico , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Membrana/metabolismo
2.
Sensors (Basel) ; 24(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276372

RESUMO

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.


Assuntos
Desempenho Atlético , Futebol , Humanos , Estações do Ano , Brasil
3.
J Arthroplasty ; 35(6): 1642-1650, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32046871

RESUMO

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.


Assuntos
Artroplastia de Quadril , Hepatite C Crônica , Luxação Congênita de Quadril , Prótese de Quadril , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Artroplastia de Quadril/efeitos adversos , Seguimentos , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
4.
Int J Sport Nutr Exerc Metab ; 30(5): 330-337, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32668408

RESUMO

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.


Assuntos
Desempenho Atlético/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Corrida/fisiologia , Futebol/fisiologia , Bicarbonato de Sódio/administração & dosagem , Adolescente , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Humanos , Concentração de Íons de Hidrogênio , Fadiga Muscular , Força Muscular , Substâncias para Melhoria do Desempenho/sangue , Bicarbonato de Sódio/sangue
5.
EMBO Rep ; 18(5): 765-780, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28330855

RESUMO

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.


Assuntos
Autofagossomos/metabolismo , Família da Proteína 8 Relacionada à Autofagia/química , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Família da Proteína 8 Relacionada à Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Membranas/química , Membranas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Fagossomos/metabolismo , Fosfatidiletanolaminas/metabolismo , Ligação Proteica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
6.
Cell Tissue Bank ; 19(4): 659-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30069709

RESUMO

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.


Assuntos
Sistema Musculoesquelético/microbiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Risco , Adulto Jovem
7.
Methods ; 75: 3-12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25526918

RESUMO

Macroautophagy (hereafter autophagy) is a highly evolutionarily conserved process essential for sustaining cellular integrity, homeostasis, and survival. Most eukaryotic cells constitutively undergo autophagy at a low basal level. However, various stimuli, including starvation, organelle deterioration, stress, and pathogen infection, potently upregulate autophagy. The hallmark morphological feature of autophagy is the formation of the double-membrane vesicle known as the autophagosome. In yeast, flux through the pathway culminates in autophagosome-vacuole fusion, and the subsequent degradation of the resulting autophagic bodies and cargo by vacuolar hydrolases, followed by efflux of the breakdown products. Importantly, aberrant autophagy is associated with diverse human pathologies. Thus, there is a need for ongoing work in this area to further understand the cellular factors regulating this process. The field of autophagy research has grown exponentially in recent years, and although numerous model organisms are being used to investigate autophagy, the baker's yeast Saccharomyces cerevisiae remains highly relevant, as there are significant and unique benefits to working with this organism. In this review, we will focus on the current methods available to evaluate and monitor autophagy in S. cerevisiae, which in several cases have also been subsequently exploited in higher eukaryotes.


Assuntos
Autofagia/genética , Fagossomos/genética , Saccharomyces cerevisiae/genética , Família da Proteína 8 Relacionada à Autofagia , Humanos , Hidrolases/genética , Hidrolases/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Vacúolos/enzimologia , Vacúolos/genética
8.
Methods ; 75: 141-50, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25484341

RESUMO

Autophagy is a conserved intracellular catabolic pathway that degrades unnecessary or dysfunctional cellular components. Components destined for degradation are sequestered into double-membrane vesicles called autophagosomes, which subsequently fuse with the vacuole/lysosome delivering their cargo into the interior of this organelle for turnover. Autophagosomes are generated through the concerted action of the autophagy-related (Atg) proteins. The yeast Saccharomyces cerevisiae has been key in the identification of the corresponding genes and their characterization, and it remains one of the leading model systems for the investigation of the molecular mechanism and functions of autophagy. In particular, it is still pivotal for the study of selective types of autophagy. The objective of this review is to present detailed protocols of the methods available to monitor the progression of both nonselective and selective types of autophagy, and to discuss their advantages and disadvantages. The ultimate aim is to provide researchers with the information necessary to select the optimal approach to address their biological question.


Assuntos
Autofagia/genética , Biologia Molecular/métodos , Vacúolos/ultraestrutura , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Vacúolos/genética
10.
Int Orthop ; 39(10): 1939-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26298535

RESUMO

PURPOSE: The purpose of this study was to identify the frequency and type of intra-operative periprosthetic fractures and to describe risk factors in a single tertiary, public hospital, so that these events could be prevented, even among less experienced surgeons. METHODS: This is a cross-sectional study, based on medical records and imaging exams from the archives of a public, tertiary hospital, from April 1998 to October 2013. All consecutive patients submitted to total hip arthroplasty (THA) in the study period were evaluated, excluding unipolar or bipolar arthroplasty, surgery for the osteosynthesis of periprosthetic fractures, surgical procedure to clean infection site without component substitution and not arthroplastic surgery. Data were analyzed with chi-squared test and multivariate Cox regression. RESULTS: In the study period, 1,872 THA (1,728 patients) were performed and analyzed, with 144 bilateral cases. In 173 cases, patients had undergone surgical procedures other than THA previously, and in only 260 the surgery consisted of revision THA. There were only two cases of resection THA. Among all patients 101 intra-operative periprosthetic fractures occurred. The univariate analysis revealed a significantly higher risk of intra-operative fractures in female patients, aged more than 65 years, with indication of primary THA and the presence of a previous hip surgery. It indicated also that revision surgeries were associated with a 2.8-fold higher risk of intra-operative fracture, 2.18-fold risk in a previously operated hip and 3.9-fold in cases of resection THA or revision surgery in two stages. CONCLUSIONS: Intraoperative periprosthetic fracture is a rare event, and it is associated with revision type surgery and THA in a previously operated hip.


Assuntos
Artroplastia de Quadril/efeitos adversos , Fixação Interna de Fraturas/efeitos adversos , Fraturas Periprotéticas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Prevalência , Reoperação , Fatores de Risco , Adulto Jovem
12.
Hip Int ; 33(3): 384-390, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35114832

RESUMO

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.


Assuntos
Artroplastia de Quadril , Hipertensão , Cirurgiões , Humanos , Estados Unidos , Idoso , Tempo de Internação , Artroplastia de Quadril/efeitos adversos , Medição de Risco , Estudos Retrospectivos , Melhoria de Qualidade , Procedimentos Clínicos , Reprodutibilidade dos Testes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Hipertensão/complicações , Fatores de Risco
13.
Acta Ortop Bras ; 30(5): e251150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451786

RESUMO

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.

14.
Sci Rep ; 12(1): 21287, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494482

RESUMO

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.


Assuntos
Desempenho Atlético , Corrida , Futebol , Humanos , Masculino , Adulto Jovem , Adulto , Aceleração , Acelerometria , Sistemas de Informação Geográfica
15.
Biomark Med ; 16(9): 681-692, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35531623

RESUMO

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.


Assuntos
Injúria Renal Aguda , COVID-19 , Injúria Renal Aguda/diagnóstico , Biomarcadores , Estado Terminal , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Lipocalina-2 , Estudos Prospectivos
16.
Microbiol Immunol ; 55(10): 673-82, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21752087

RESUMO

PNAG is a major component of Staphylococcus epidermidis biofilms involved in intercellular adhesion as well as in the interaction of the biofilm with components of the host immune response. Synthesis of PNAG has been found to be regulated by several environmental factors. In the present study, the effect of glucose metabolism-dependent culture medium acidification in PNAG accumulation was evaluated. Established S. epidermidis biofilms were allowed to grow in excess glucose with or without maintained pH conditions. PNAG accumulation in these biofilms was determined by flow cytometry and fluorescence microscopy using wheat germ agglutinin as a fluorescent probe. Biofilms grown in maintained pH conditions presented significantly higher amounts of this polymer as well as higher icaA expression than biofilms grown in acidic pH conditions. Moreover, PNAG accumulation in biofilms grown in non-maintained pH conditions occurred in association with cell death. Overall, we show that glucose metabolism by decreasing the culture pH affects biofilm physiology in respect to PNAG production and cell death. The reported in vitro modulation of PNAG accumulation within S. epidermidis biofilms further highlights the role of environment on determining the biofilm physiological state.


Assuntos
Acetilglucosamina/biossíntese , Biofilmes , Glucose/metabolismo , Staphylococcus epidermidis/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/crescimento & desenvolvimento
17.
Surg Neurol Int ; 12: 154, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948324

RESUMO

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.

18.
Arthroscopy ; 26(8): 1053-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20678702

RESUMO

PURPOSE: The aim of this study was to evaluate the type and incidence of complications during the development of hip arthroscopic techniques. METHODS: A retrospective series of 194 files of patients treated with hip arthroscopy in a tertiary hospital from December 1999 to March 2008 was reviewed for complications. The incidence of complications was recorded consecutively for each group of 30 patients and in intervals of 2 years. A comparison between the complication rates was performed within the time frames and the set of cases. The type and severity of complications were also recorded. RESULTS: There were 12 complications (6.1%) in this series. Of these, 5 were neurologic (2.6%), 4 were musculoskeletal (2%), and 3 were vascular/ischemic (1.5%). According to severity, 2 were considered major complications (1%), 8 were intermediate (4.1%), and 2 were minor (1%). The incidence of complications did not change with time (P = .959) or with the number of cases performed (P = .771), but different types of complications occurred along the learning curve. CONCLUSIONS: The nature of complications changed with experience, but no significant variation in the incidence was observed over the 9-year period of experience with hip arthroscopy. LEVEL OF EVIDENCE: Level IV, therapeutic case series.


Assuntos
Artroscopia/efeitos adversos , Articulação do Quadril/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
J Biomater Appl ; 35(3): 405-421, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32571173

RESUMO

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.


Assuntos
Materiais Revestidos Biocompatíveis/química , Géis/química , Hidróxidos/química , Compostos de Potássio/química , Dióxido de Silício/química , Titânio/química , Animais , Calcificação Fisiológica , Adesão Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis/metabolismo , Implantação Dentária , Humanos , Camundongos , Osteogênese , Silanos/química , Propriedades de Superfície , Titânio/metabolismo
20.
J Laparoendosc Adv Surg Tech A ; 19 Suppl 1: S191-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19021469

RESUMO

BACKGROUND: Esophageal replacement (ER) is indicated for long gap esophageal atresia (LGEA) when anastomosisis not possible, especially in cases without fistula or when elongation techniques have failed. The authors show their techniques and analyze preliminary results of the laparoscopic gastric pull-up (LGPU) for ERin LGEA. METHODS: Four children with LGEA admitted for ER (three type A, one type C) underwent LGPU. Using three ports, including the gastrostomy site, surgical steps included releasing the stomach while preserving the right gastric and gastroepiploic arteries, pyloromyoplasty, and retromediastinal blunt dissection through a laparoscopic view. The esophagostomy was freed and the superior mediastinum was dissected, the stomach was pulled up for cervical anastomosis to the distal esophagus in two cases and to the gastric fundus in another two, adding thoracoscopy in two. RESULTS: All operations were performed without major surgical complications, conversion, death, or reoperation.There were no abdominal complications. Two children presented atelectasis and one case evolved to pneumonia.A girl had a cervical fistula close spontaneously. Transanastomotic tube feeding began after 2-4 days,oral feeding after 8-12 days. Mild anastomotic stenosis (2) was resolved with endoscopic dilatations. After a follow-up of 9-26 months all children have functional grafts and satisfactory oral feeding. One child has duodeno-gastric reflux. Cosmetics have been excellent. The children have the same scars they had before (umbilicus,gastrostomy, and esophagostomy) plus a tiny 3 mm scar on the right flank. CONCLUSIONS: Video-assisted esophageal replacement with the stomach for LGEA can be safely performed in children and infants, even after a previous mediastinal operation; however, larger comparative series are required in the future.


Assuntos
Atresia Esofágica/cirurgia , Laparoscopia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Seguimentos , Humanos , Lactente , Masculino , Complicações Pós-Operatórias
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