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1.
Eur J Orthop Surg Traumatol ; 28(7): 1359-1367, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29693238

RESUMO

PURPOSE: The aim of our study is to compare the mechanical resistance of two screw configurations in fixating type II Pauwels femoral neck fractures. METHODS: Fifteen synthetic models of femur bones in young adults were divided into three equal groups: intact (G1), models with fixation of a 5.0-mm failure zone created in the posterior cortex of the femoral neck using an L-shaped screw arrangement (G2, n = 5), and models with an identical failure zone fixated using an inverted triangle assembly (G3, n = 5). Model strength (axial loading) and rotational deviation of the fragments were load-tested until a 5.0-mm displacement was reached (step 1) and then until failure, here considered as 10.0 mm displacement in G2 and G3 or femoral neck fracture in G1 (step 2). RESULTS: In step 1, the mean resistance in G1 was 1593 N (standard deviation [SD] of 62 N); this value in G2 was 1261 N (SD 49 N) and in G3 was 1074 N (SD 153 N). During step 2, the value for G1 was 2247 N (SD 84 N), for G2 was 1895 N (SD 69 N), and for G3 was 1523 N (SD 280 N). G3 (the inverted triangle assembly) showed a significantly lower maximum load than the group using the L-shaped assembly (G2) and the control group (G1), which was significant using Kruskal-Wallis analysis of variance (p = 0.002). CONCLUSION: Under test conditions in synthetic bone, fixation using a L-shaped screw assembly provides greater mechanical resistance than an inverted triangle assembly.


Assuntos
Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Adulto , Fenômenos Biomecânicos , Fraturas do Colo Femoral/classificação , Fraturas do Colo Femoral/fisiopatologia , Fêmur/cirurgia , Humanos , Fenômenos Mecânicos , Modelos Anatômicos , Adulto Jovem
2.
Intern Med J ; 46(10): 1172-1181, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26865245

RESUMO

BACKGROUND: The epidemiology of in-hospital cardiac arrests (IHCA) in Australia and New Zealand (ANZ) has not been systematically assessed. AIM: To conduct a systematic review of the frequency, characteristics and outcomes of adult IHCA in ANZ. METHODS: Medline search for studies published in 1964-2014 using MeSH terms 'arrest AND hospital AND Australia', 'arrest AND hospital AND New Zealand', 'inpatient AND arrest AND Australia' and 'inpatient AND arrest AND New Zealand'. RESULTS: We screened 934 studies, analysed 50 and included 30. Frequency of IHCA ranged from 1.31 to 6.11 per 1000 admissions in 4 population studies and 0.58 to 4.59 per 1000 in 16 cohort studies. The frequency was 4.11 versus 1.32 per 1000 admissions in hospitals with rapid response system (RRS) compared with those without (odds ratio: 0.32; 95% confidence interval 0.28-0.37; P < 0.001). On aggregate, the initial cardiac rhythm was ventricular tachycardia/fibrillation in 31.4% (range 19.0-48.8%) in 10 studies reporting such data. On aggregate, IHCA were witnessed in 80.2% cases (three studies) and monitored patients in 53.4% cases (four studies). Details of life support were poorly documented. On aggregate, return of spontaneous circulation occurred in 46.0% of patients. Overall, 74.6% (range 59.4-77.5%) died in-hospital but survival was higher among monitored or younger patients, in those with a shockable rhythm, or during working hours. CONCLUSION: IHCA are uncommon in ANZ and three quarters die in-hospital. However, their frequency varies markedly across institutions and may be affected by the presence of RRS. Where reported, the long-term outcomes survivors appear to have acceptable neurological outcomes.


Assuntos
Parada Cardíaca/mortalidade , Taquicardia Ventricular/complicações , Taquicardia Ventricular/epidemiologia , Fibrilação Ventricular/complicações , Fibrilação Ventricular/epidemiologia , Fatores Etários , Austrália , Reanimação Cardiopulmonar , Parada Cardíaca/terapia , Mortalidade Hospitalar , Humanos , Monitorização Fisiológica , Nova Zelândia , Análise de Sobrevida , Fatores de Tempo
3.
Anaesthesia ; 70(10): 1140-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26010229

RESUMO

We measured carotid and brachial artery blood flow by Doppler ultrasound in 11 human volunteers, and related these to cardiac index and to each other. The median (IQR [range]) carotid arterial blood flow was 0.334 (0.223-0.381 [0.052-0.563]) l.min(-1) on the right and 0.315 (0.223-0.369 [0.061-0.690]) l.min(-1) on the left. The brachial arterial blood flow was 0.049 (0.033-0.062 [0.015-0.204]) l.min(-1) on the right and 0.039 (0.027-0.054 [0.011-0.116]) on the left. Cardiac index was 3.2 (2.8-3.5 [1.9-5.4]) l.min(-1) .m(-2) . There was a moderate to good correlation between right-and left-sided flows (brachial: ρ = 0.45; carotid: ρ = 0.567). Brachial and carotid flow had no or a negative correlation with cardiac index (right brachial: ρ = -0.145, left brachial: ρ = -0.349; right carotid: ρ = -0.376, left carotid: ρ = -0.285). In contrast to some previous studies, we found that Doppler-estimated peripheral arterial blood flows only show a weak correlation with cardiac index and cannot be used to provide non-invasive estimates of cardiac index in man.


Assuntos
Artéria Braquial/fisiologia , Débito Cardíaco/fisiologia , Artéria Carótida Primitiva/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Artéria Braquial/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Fluxo Sanguíneo Regional/fisiologia , Reprodutibilidade dos Testes , Ultrassonografia Doppler/métodos
4.
Perfusion ; 30(4): 291-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25070898

RESUMO

We report the case of a patient with cardiovascular and respiratory failure due to severe anaphylaxis requiring multiple extracorporeal membrane oxygenation (ECMO) cannulation strategies to provide adequate oxygen delivery and ventilatory support during a period of rapid physiological change. ECMO provides partial or complete support of oxygenation-ventilation and circulation. The choice of which ECMO modality to use is governed by anatomical (vessel size, cardiovascular anatomy and previous surgeries) and physiological (respiratory and/or cardiac failure) factors. The urgency with which ECMO needs to be implemented (emergency cardiopulmonary resuscitation (eCPR), urgent, elective) and the institutional experience will also influence the type of ECMO provided. Here we describe a 12-year-old schoolgirl who, having been resuscitated with peripheral veno-venous (VV) ECMO for severe hypoxemia due to status asthmaticus in the setting of acute anaphylaxis, required escalation to peripheral veno-arterial (VA) ECMO for precipitous cardiovascular deterioration. Insufficient oxygen delivery for adequate cellular metabolic function and possible cerebral hypoxia due to significant differential hypoxia necessitated ECMO modification. After six days of central (transthoracic) VA ECMO support and 21 days of intensive care unit (ICU) care, she made a complete recovery with no neurological sequelae. The use of ECMO support warrants careful consideration of the interplay of a patient's pathophysiology and extracorporeal circuit dynamics. Particular emphasis should be placed on the potential for mismatch between cardiovascular and respiratory support as well as the need to meet metabolic demands through adequate cerebral, coronary and systemic oxygenation. Cannulation strategies occasionally require alteration to meet and anticipate the patient's evolving needs.


Assuntos
Anafilaxia/terapia , Oxigenação por Membrana Extracorpórea , Insuficiência Cardíaca/terapia , Hipóxia/terapia , Insuficiência Respiratória/terapia , Estado Asmático/terapia , Anafilaxia/complicações , Anafilaxia/fisiopatologia , Criança , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipóxia/etiologia , Hipóxia/fisiopatologia , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Estado Asmático/complicações , Estado Asmático/fisiopatologia
5.
PLoS One ; 19(5): e0299390, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38696477

RESUMO

OBJECTIVE: To evaluate the association of a validated chest computed tomography (Chest-CT) severity score in COVID-19 patients with their respiratory outcome in the Intensive Care Unit. METHODS: A single-center, prospective study evaluated patients with positive RT-PCR for COVID-19, who underwent Chest-CT and had a final COVID-19 clinical diagnosis needing invasive mechanical ventilation in the ICU. The admission chest-CT was evaluated according to a validated Chest-CT Severity Score in COVID-19 (Chest-CTSS) divided into low ≤50% (<14 points) and >50% high (≥14 points) lung parenchyma involvement. The association between the initial score and their pulmonary clinical outcomes was evaluated. RESULTS: 121 patients were clustered into the > 50% lung involvement group and 105 patients into the ≤ 50% lung involvement group. Patients ≤ 50% lung involvement (<14 points) group presented lower PEEP levels and FiO2 values, respectively GEE P = 0.09 and P = 0.04. The adjusted COX model found higher hazard to stay longer on invasive mechanical ventilation HR: 1.69, 95% CI, 1.02-2.80, P = 0.042 and the adjusted logistic regression model showed increased risk ventilator-associated pneumonia OR = 1.85 95% CI 1.01-3.39 for COVID-19 patients with > 50% lung involvement (≥14 points) on Chest-CT at ICU admission. CONCLUSION: COVID-19 patients with >50% lung involvement on Chest-CT admission presented higher chances to stay longer on invasive mechanical ventilation and more chances to developed ventilator-associated pneumonia.


Assuntos
COVID-19 , Estado Terminal , Unidades de Terapia Intensiva , Respiração Artificial , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Humanos , COVID-19/diagnóstico por imagem , COVID-19/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , SARS-CoV-2/isolamento & purificação , Pulmão/diagnóstico por imagem
6.
Curr Opin Crit Care ; 19(6): 624-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24240829

RESUMO

PURPOSE OF REVIEW: Decisions to limit life-sustaining therapy (DLLST) in the ICU are used to uphold patients' autonomy, protect them from non-beneficial treatment and fairly distribute resources. The institution of these decisions is complex, with a variety of qualitative and quantitative data published. This review aims to summarize the main issues and review the contemporary research findings on this subject. RECENT FINDINGS: DLLST are used in a variety of clinical and non-clinical situations, before and after ICU admission, and are not always part of end-of-life management. There are many dilemmas and barriers that beset their institution. Many ICU physicians feel inadequately trained to carry them out and they are frequently a source of conflict. A variety of strategies have been examined to improve their institution, including advanced directives, intensive communication strategies and family information leaflets, many of which have improved patient and family-centred outcomes. SUMMARY: There are a number of uncertainties that beset the institution of DLLST in the ICU; however, a variety of research has improved our ability to understand and implement them. This review frames some of the dilemmas and discusses some of the procedural strategies that have been used to improve outcomes.


Assuntos
Unidades de Terapia Intensiva , Cuidados para Prolongar a Vida , Assistência Terminal , Suspensão de Tratamento , Comunicação , Tomada de Decisões , Eutanásia Passiva/ética , Eutanásia Passiva/tendências , Família/psicologia , Feminino , Humanos , Cuidados para Prolongar a Vida/ética , Cuidados para Prolongar a Vida/psicologia , Masculino , Autonomia Pessoal , Relações Profissional-Família , Assistência Terminal/ética , Assistência Terminal/psicologia
7.
Sci Rep ; 13(1): 18504, 2023 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-37898681

RESUMO

This study aimed to evaluate the effect of two restrictive cumulative fluid balance (CFB) trends on survival and on major clinical outcomes in invasively ventilated patients with moderate to severe respiratory distress syndrome (ARDS) due to SARS-CoV-2. Prospective data collection was conducted on patients in the intensive care unit (ICU) originating from a tertiary university hospital. The primary outcomes were the risk association between the CFB trend during D0 to D7 and 28-day survival. The secondary outcomes were ICU mortality, in-hospital mortality, the need for invasive ventilation at D28, administration of vasoactive drugs at D7, time on invasive ventilation after D7, and length of ICU and hospital stay. 171 patients were enrolled in the study and divided according to their CFB trends during seven days of follow-up using model-based clustering [median CFB negative trend (n = 89) - 279 ml (- 664 to 203) and (n = 82) median CFB positive trend 1362 ml (619-2026)]. The group with CFB negative trend showed a higher chance of surviving 28-day in the ICU (HR: 0.62, 95% CI 0.41-0.94, p = 0.038). Moreover, this group had a reduced length of stay in the ICU, 11 (8-19) days versus 16.5 (9-29) days p = 0.004 and presented lower rates (OR = 0.22; 95% CI 0.09-0.52) of invasive ventilation after 28-days in the ICU. In patients invasively ventilated with moderate to severe ARDS due to COVID-19, the collective who showed a negative trend in the CFB after seven days of invasive ventilation had a higher chance of surviving 28 days in the ICU and lower length of stay in the ICU.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Humanos , COVID-19/complicações , COVID-19/terapia , SARS-CoV-2 , Respiração Artificial , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/terapia , Unidades de Terapia Intensiva , Equilíbrio Hidroeletrolítico
8.
Orthopedics ; 45(4): e220-e225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35245137

RESUMO

Articular fractures of the distal humerus in adults are challenging fractures requiring adequate surgical exposure for optimum reconstruction. Most commonly, an articular osteotomy of the olecranon is performed, but complications have been reported related to both creating and repairing the articular osteotomy. We describe the use of an extra-articular olecranon osteotomy for approaching articular fractures of the distal humerus. We highlight the surgical steps required to obtain adequate exposure facilitating anatomical reduction, stable fixation, and early range of motion of the elbow joint. This technique can be added to the surgeon's armamentarium for the management of these complex injuries. [Orthopedics. 2022;45(4):e220-e225.].


Assuntos
Lesões no Cotovelo , Articulação do Cotovelo , Fraturas do Úmero , Fraturas Intra-Articulares , Olécrano , Adulto , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Úmero/cirurgia , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia , Olécrano/cirurgia , Amplitude de Movimento Articular , Resultado do Tratamento
9.
ISA Trans ; 128(Pt A): 581-592, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34815072

RESUMO

A robust current control approach with disturbance cross-coupling compensation for permanent magnet synchronous motor drives (PMSM) is proposed in this paper. The proposed approach can enhance the reference tracking and provides a robust option for current control of PMSM drives. A discrete-time sliding mode current controller is proposed. The PMSM model includes the digital implementation delay, present due to the discrete-time algorithm execution. A discrete-time backstepping disturbance observer is developed, being combined to the sliding mode controller as a means to improve the robustness and tracking capability. The effects of coupling, parametric uncertainties and load disturbances are compensated by the backstepping disturbance observer. The stability analysis of the combined system is presented and the limits for overall system stability are discussed. Simulations and experimental results validate the combined scheme and demonstrate the good performance of the proposal.

10.
Eur J Trauma Emerg Surg ; 47(6): 1911-1920, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32144445

RESUMO

PURPOSE: Despite the fact that open reduction and internal fixation with a plate, either non-locked or locked, is the standard of care for managing lateral malleolus fractures, intramedullary (IM) fixation of the fibula has been recently introduced as an alternative, mainly for some potential complicated situations. We hypothesized that almost all patterns of distal fibula fracture can be safely fixed with an IM device, with the potential benefit of providing biomechanical efficiency, but using a soft-tissue friendly implant. Here, we present a multicenter case series based on a proposed algorithm. PATIENTS AND METHODS: Sixty-nine consecutive patients were managed with fibular IM fixation for closed malleolar fractures. Twenty patients were managed by IM screw fixation and 49 by fibular nailing. Outcome was measured both according to the American Orthopaedic Foot and Ankle Society (AOFAS) score for ankle and hindfoot, and the time to bone union. RESULTS: The mean AOFAS for Group I was 99.35 ± 1.95 points and that for Group II was 89.30 ± 16.98 points. There were no significant differences between the fracture pattern, according to the Lauge-Hansen classification, and post-operative levels of pain and functional activity among patients in both groups (p > 0.05). All fractures healed uneventfully in both groups. The mean time to union for Group I was 8.15 weeks and for Group II was 8.25 weeks (p > 0.05). CONCLUSION: In this multicenter case series, intramedullary fixation for the lateral malleolus fracture presented itself as a viable and safe option for the treatment of almost all patterns of fibula fracture in adults. Overall, we were able to demonstrate the potential indications of the proposed algorithm for the choice of IM implant for the lateral malleolus fracture in terms of the Lauge-Hansen staged classification.


Assuntos
Fraturas do Tornozelo , Fixação Intramedular de Fraturas , Adulto , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Placas Ósseas , Fíbula/diagnóstico por imagem , Fíbula/cirurgia , Fixação Interna de Fraturas , Humanos , Resultado do Tratamento
11.
J Hosp Infect ; 104(2): 193-197, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31628957

RESUMO

Increased public awareness of antimicrobial resistance (AMR) is a key component of effective antimicrobial stewardship strategies. Educational theatre combined with an expert panel was used to engage the public about AMR through delivery of a play entitled 'The drugs don't work'. Audience knowledge and understanding of AMR were measured by pre- and post-play questionnaires. Performance of the play and discussion with the expert panel significantly improved audience knowledge and understanding of AMR, including antibiotic misuse and prescribing. Educational theatre provides a positive learning experience and is an innovative method of public engagement to disseminate important public health messages.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Jogos e Brinquedos , Opinião Pública , Estudantes , Reino Unido , Adulto Jovem
12.
J Exp Orthop ; 7(1): 2, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953619

RESUMO

PURPOSE: The aim of this study is to compare the biomechanical behavior of three different fixation constructions currently used for buttressing the posteromedial shearing tibial plateau fragment. Our hypothesis is that non-locked implants provide sufficient comparable stability in posteromedial tibial plateau fractures as locked implants. METHODS: Fifteen left synthetic tibiae from a single manufacturing batch were used to create a posteromedial shear tibial plateau fracture. The fracture was buttressed with three different posteriorly placed five-hole straight small-fragment plate. Five models were fixed with a one-third tubular plate (TTP), five models with a dynamic compression plate (DCP), and five models with a locking compression plate (LCP). All groups were tested to vertical subsidence (Stage 1). In the same experiment (Stage 2), TTP and DCP groups were tested until catastrophic failure. Force versus displacement curves were obtained in the two stages of the experiment. RESULTS: Stage 1 - There was no significant difference in stiffness (p = 0.89), subsidence up to 2 mm (p = 0.38), and energy (p = 0.36) among the three fixation constructions. Stage 2 - Yield load revealed significantly less yield strength for the TTP group as compared with the DCP group (p = 0.048). However, there was no significant difference in maximum load to failure among the TTP and DCP fixation constructions (p = 0.16). CONCLUSION: Placement of either a locked or non-locked small fragment straight plate to buttress the posteromedial shear tibial plateau fragment has a similar biomechanical behavior. When the implant is positioned to buttress the shearing fragment it maximizes biomechanical stiffness.

13.
Science ; 258(5079): 60-6, 1992 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-1359640

RESUMO

The human Y chromosome was physically mapped by assembling 196 recombinant DNA clones, each containing a segment of the chromosome, into a single overlapping array. This array included more than 98 percent of the euchromatic portion of the Y chromosome. First, a library of yeast artificial chromosome (YAC) clones was prepared from the genomic DNA of a human XYYYY male. The library was screened to identify clones containing 160 sequence-tagged sites and the map was then constructed from this information. In all, 207 Y-chromosomal DNA loci were assigned to 127 ordered intervals on the basis of their presence or absence in the YAC's, yielding ordered landmarks at an average spacing of 220 kilobases across the euchromatic region. The map reveals that Y-chromosomal genes are scattered among a patchwork of X-homologous, Y-specific repetitive, and single-copy DNA sequences. This map of overlapping clones and ordered, densely spaced markers should accelerate studies of the chromosome.


Assuntos
Genoma Humano , Cromossomo Y , Sequência de Bases , Centrômero , Clonagem Molecular , Impressões Digitais de DNA , Biblioteca Gênica , Genes Fúngicos , Humanos , Masculino , Dados de Sequência Molecular , Família Multigênica , Polimorfismo de Fragmento de Restrição , Homologia de Sequência , Sitios de Sequências Rotuladas , Cromossomo X
14.
Science ; 258(5079): 52-9, 1992 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-1439769

RESUMO

A deletion map of the human Y chromosome was constructed by testing 96 individuals with partial Y chromosomes for the presence or absence of many DNA loci. The individuals studied included XX males, XY females, and persons in whom chromosome banding had revealed translocated, deleted, isodicentric, or ring Y chromosomes. Most of the 132 Y chromosomal loci mapped were sequence-tagged sites, detected by means of the polymerase chain reaction. These studies resolved the euchromatic region (short arm, centromere, and proximal long arm) of the Y chromosome into 43 ordered intervals, all defined by naturally occurring chromosomal breakpoints and averaging less than 800 kilobases in length. This deletion map should be useful in identifying Y chromosomal genes, in exploring the origin of chromosomal disorders, and in tracing the evolution of the Y chromosome.


Assuntos
Mapeamento Cromossômico , Deleção de Genes , Genoma Humano , Cromossomo Y , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sitios de Sequências Rotuladas
15.
PLoS One ; 14(7): e0220523, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361778

RESUMO

BACKGROUND: The purpose of this study was to evaluate the role of a non-locking plate applied to the anteromedial surface of the proximal humerus on loads at the implant-bone interface of non-locking and locking lateral plate fixation of proximal humeral fractures with a medial gap. METHODS: Twenty synthetic humeri models were used. In fifteen, the proximal portion of the humerus was osteotomized to create a two-part surgical neck fracture, with a 10-mm medial gap and a 5-mm lateral gap; five models were controls. In the osteotomized humeri, five models were stabilized with a locking lateral plate (group L), five with a locking lateral plate and an anteromedial non-locking plate (group L+T), and five with a non-locking lateral plate and a non-locking anteromedial plate (group T+T). All humeri were tested under axial loading until catastrophic failure, which was characterized as complete closure of the medial gap. Stiffness was calculated using force vs. displacement curves. The data were analyzed via descriptive and inferential studies, at a 5% significance level. RESULTS: Statistically significant differences were seen among all the constructions. The combination of a lateral locking plate with an anteromedial non-locking plate (group L+T) was the stiffest construction, while the combination of a non-locking lateral plate with a non-locking anteromedial plate (group T+T) was the least stiff, even in comparison with a single locking lateral plate (p = 0.01). When the two groups which utilized a lateral locking plate (groups L+T and L) were compared, the group with additional anteromedial support demonstrated greater stiffness (p = 0.03), and stiffness values for the control group comprised of intact humeri models were even higher (p = 0.01). CONCLUSION: Combining a lateral locking plate with a non-locking anteromedial plate provides a stiffer construction for fixation of unstable two-part proximal humerus fractures with a medial gap. Mechanical benefits of medial support with a second non-locking antero-medial plate seems to be related with better construct stability in terms of strength and fatigue, potentially reducing the risk of varus collapse of the humerus head and fracture healing disturbances.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Lesões do Pescoço/cirurgia , Fraturas do Ombro/cirurgia , Fenômenos Biomecânicos , Parafusos Ósseos , Estudos de Casos e Controles , Osso Cortical , Fixação Interna de Fraturas/classificação , Humanos
16.
J Exp Orthop ; 6(1): 18, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049738

RESUMO

BACKGROUND: The biomechanical behavior of Pauwels type III fractures should be taken into consideration when performing internal fixation, since this repair should resist the shear force inherent in the vertical fracture line to the greatest extent possible. Recently, the use of a small fragment plate on the medial face of the femoral neck has been proposed by some authors, with satisfactory initial results. In the current study we analyze the mechanical role a medial plate used as a buttress plate for Pauwels type III femoral neck fractures, comparing the resistance of two fixation configurations using three cannulated screws. METHODS: Pauwels type III fractures were simulated in synthetic bones models and two groups were created, one of those using two parallel screws at the bottom of the femoral neck and the third screw crossing the fracture horizontally (G1), and the other fixed in the same arrangement as G1, but with the addition of a medial side plate at the apex of the fracture (G2). The constructs were subjected to axial loading until catastrophic failure. RESULTS: The addition of a medial plate buttressing the femoral neck increased significantly the resistance to maximum loading (p = 0.003). CONCLUSION: Use of a medial buttress plate results in a mechanically superior construction for Pauwels type III fractures fixed with multiple cannulated screws. LEBEL OF EVIDENCE: Level IV. Biomechanical comparative study.

17.
Sci Adv ; 5(9): eaax4489, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31579826

RESUMO

Most studies on human immunity to malaria have focused on the roles of immunoglobulin G (IgG), whereas the roles of IgM remain undefined. Analyzing multiple human cohorts to assess the dynamics of malaria-specific IgM during experimentally induced and naturally acquired malaria, we identified IgM activity against blood-stage parasites. We found that merozoite-specific IgM appears rapidly in Plasmodium falciparum infection and is prominent during malaria in children and adults with lifetime exposure, together with IgG. Unexpectedly, IgM persisted for extended periods of time; we found no difference in decay of merozoite-specific IgM over time compared to that of IgG. IgM blocked merozoite invasion of red blood cells in a complement-dependent manner. IgM was also associated with significantly reduced risk of clinical malaria in a longitudinal cohort of children. These findings suggest that merozoite-specific IgM is an important functional and long-lived antibody response targeting blood-stage malaria parasites that contributes to malaria immunity.


Assuntos
Anticorpos Antiprotozoários/imunologia , Interações Hospedeiro-Parasita/imunologia , Imunidade , Imunoglobulina M/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Plasmodium falciparum/imunologia , Adolescente , Adulto , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Antígenos de Protozoários/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Antimicrob Agents Chemother ; 52(10): 3633-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18676882

RESUMO

This study evaluated a model of skin permeation to determine the depth of delivery of chlorhexidine into full-thickness excised human skin following topical application of 2% (wt/vol) aqueous chlorhexidine digluconate. Skin permeation studies were performed on full-thickness human skin using Franz diffusion cells with exposure to chlorhexidine for 2 min, 30 min, and 24 h. The concentration of chlorhexidine extracted from skin sections was determined to a depth of 1,500 microm following serial sectioning of the skin using a microtome and analysis by high-performance liquid chromatography. Poor penetration of chlorhexidine into skin following 2-min and 30-min exposures to chlorhexidine was observed (0.157 +/- 0.047 and 0.077 +/- 0.015 microg/mg tissue within the top 100 microm), and levels of chlorhexidine were minimal at deeper skin depths (less than 0.002 microg/mg tissue below 300 microm). After 24 h of exposure, there was more chlorhexidine within the upper 100-microm sections (7.88 +/- 1.37 microg/mg tissue); however, the levels remained low (less than 1 microg/mg tissue) at depths below 300 microm. There was no detectable penetration through the full-thickness skin. The model presented in this study can be used to assess the permeation of antiseptic agents through various layers of skin in vitro. Aqueous chlorhexidine demonstrated poor permeation into the deeper layers of the skin, which may restrict the efficacy of skin antisepsis with this agent. This study lays the foundation for further research in adopting alternative strategies for enhanced skin antisepsis in clinical practice.


Assuntos
Anti-Infecciosos Locais/farmacocinética , Clorexidina/farmacocinética , Pele/metabolismo , Administração Tópica , Anti-Infecciosos Locais/administração & dosagem , Cateterismo Venoso Central/métodos , Clorexidina/administração & dosagem , Feminino , Humanos , Técnicas In Vitro , Modelos Biológicos , Permeabilidade , Pele/efeitos dos fármacos , Pele/microbiologia , Soluções
19.
J Antimicrob Chemother ; 62(3): 522-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18544601

RESUMO

OBJECTIVES: Persistent contamination of surfaces by spores of Clostridium difficile is a major factor influencing the spread of C. difficile-associated diarrhoea (CDAD) in the clinical setting. In recent years, the antimicrobial efficacy of metal surfaces has been investigated against microorganisms including methicillin-resistant Staphylococcus aureus. This study compared the survival of C. difficile on stainless steel, a metal contact surface widely used in hospitals, and copper surfaces. METHODS: Antimicrobial efficacy was assessed using a carrier test method against dormant spores, germinating spores and vegetative cells of C. difficile (NCTC 11204 and ribotype 027) over a 3 h period in the presence and absence of organic matter. RESULTS: Copper metal eliminated all vegetative cells of C. difficile within 30 min, compared with stainless steel which demonstrated no antimicrobial activity (P < 0.05). Copper significantly reduced the viability of spores of C. difficile exposed to the germinant (sodium taurocholate) in aerobic conditions within 60 min (P < 0.05) while achieving a >or=2.5 log reduction (99.8% reduction) at 3 h. Organic material did not reduce the antimicrobial efficacy of the copper surface (P > 0.05). CONCLUSIONS: The use of copper surfaces within the clinical environment and application of a germination solution in infection control procedures may offer a novel way forward in eliminating C. difficile from contaminated surfaces and reducing CDAD.


Assuntos
Anti-Infecciosos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Cobre/farmacologia , Equipamentos e Provisões/microbiologia , Esporos/efeitos dos fármacos , Contagem de Colônia Microbiana , Viabilidade Microbiana , Aço Inoxidável/farmacologia , Fatores de Tempo
20.
J Hosp Infect ; 70(4): 314-20, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18848735

RESUMO

SUMMARY: Between January 2005 and December 2005, 199 meticillin-resistant Staphylococcus aureus (MRSA) isolates were obtained from non-hospitalised patients presenting skin and soft tissue infections to local general practitioners. The study area incorporated 57 surgeries from three Primary Care Trusts in the Lichfield, Tamworth, Burntwood, North and East Birmingham regions of Central England, UK. Following antibiotic susceptibility testing, pulsed-field gel electrophoresis, Panton-Valentine leukocidin gene detection and SCCmec element assignment, 95% of the isolates were shown to be related to hospital epidemic strains EMRSA-15 and EMRSA-16. In total 87% of the isolate population harboured SCCmec IV, 9% had SCCmec II and 4% were identified as carrying novel SCCmec IIIa(-mecI). When mapped to patient home postcode, a diverse distribution of isolates harbouring SCCmec II and SCCmec IV was observed; however, the majority of isolates harbouring SCCmec IIIa(-mecI) were from patients residing in the north-west of the study region, highlighting a possible localised clonal group. Transmission of MRSA from the hospital setting into the surrounding community population, as demonstrated by this study, warrants the need for targeted patient screening and decolonisation in both the clinical and community environments.


Assuntos
Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/epidemiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Proteínas de Bactérias/genética , Infecções Comunitárias Adquiridas/microbiologia , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Meticilina/farmacologia , Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Fenótipo , Reação em Cadeia da Polimerase , Infecções Estafilocócicas/microbiologia , Reino Unido/epidemiologia
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