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A time-resolved, phase-sensitive second harmonic generation (SHG) method to probe the excited state dynamics of interfacial species is presented. It is based on an interference measurement between the SHG from a sample and a local oscillator generated at a reference surface in which an entire interference pattern is recorded in a single shot by using a spatially varying phase unit comprised of a pair of wedges that sandwich the reference sample. In combination with 30 kHz modulation of the experiment, shot-to-shot pump-probe measurements are presented. The technique is characterised by measuring the time-resolved change in the amplitude and phase of the interference pattern due to the excited state dynamics of the dye malachite green at the air/water interface. The key attributes of the technique are its excellent phase stability and sensitivity, and relatively short data acquisition times.
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BACKGROUND: A proportion of patients who sustain upper limb fractures develop post-traumatic stiffness (PTS), which may progress in a similar way to primary frozen shoulder (PFS). We have had success in treating PFS with manipulation under anaesthetic (MUA) and therefore treated PTS using MUA. Oxford Shoulder Scores (OSS), range of motion (ROM) data pre- and post-MUA, and the need for repeat procedure were compared. METHODS: Sixty-four patients with PTS following an upper limb fracture, unresponsive to conservative measures, were seen between 1 January 1999 and 1 November 2015. Thirty-two patients had sustained a proximal humeral fracture, six of whom had a concurrent shoulder dislocation. MUA was performed using a standard technique. The results were compared with 487 PFS patients undergoing the same procedure. RESULTS: There was no significant difference in ROM change between the groups. Improvement in OSS was slightly greater in the PFS group (17 versus 14, p = 0.005) but, upon subgroup analysis of the PTS group, no significant difference was found for patients presenting with humeral fractures alone. CONCLUSIONS: MUA results for PTS following upper limb fracture are comparable to MUA for PFS. We therefore recommend MUA in PTS cases where conservative methods have failed.
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Electron-transfer reactions at ambient aqueous interfaces represent one of the most fundamental and ubiquitous chemical reactions. Here the dynamics of the charge transfer to solvent (CTTS) reaction from iodide was probed at the ambient water/air interface by phase-sensitive transient second-harmonic generation. Using the three allowed polarization combinations, distinctive dynamics assigned to the CTTS state evolution and to the subsequent solvating electron-iodine contact pair have been resolved. The CTTS state is asymmetrically solvated in the plane of the surface, while the subsequent electron solvation dynamics are very similar to those observed in the bulk, although slightly faster. Between 3 and 30 ps, a small phase shift distinguishes an electron bound in a contact pair with iodine and a free hydrated electron at the water/air interface. Our results suggest that the hydrated electron is fully solvated in a region of reduced water density at the interface.
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A 72-year-old lady underwent a Copeland hemiarthoplasty of the shoulder for rotator cuff arthropathy with a good functional outcome. Her past medical history included previous management of a malignant melanoma. Several years following arthroplasty surgery, she acutely developed signs and symptoms of prosthetic joint infection. The present case report describes the metastatic spread of malignant melanoma mimicking that of prosthetic sepsis.
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INTRODUCTION: Patients with secondary frozen shoulder following anterior dislocation were treated with manipulation under anaesthesia (MUA) and injection. METHODS: Ten patients included in study. Oxford Shoulder Scores (OSS), range of motion (ROM) and need for any further treatment measured. RESULTS: Mean follow-up of 93 weeks. OSS and ROM improved in all patients. Three patients required repeat MUA. Two patients developed recurrent instability. DISCUSSION: Secondary frozen shoulder may be more recalcitrant. Recurrent instability is a risk following anterior shoulder dislocation. It is feasible that by performing an MUA to maximise mobility, stability may be sacrificed. It should be performed with caution.
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A methodology based on time-resolved, phase-sensitive second harmonic generation (SHG) for probing the excited state dynamics of species at interfaces is presented. It is based on an interference measurement between the SHG from the sample and a local oscillator generated at a reference together with a lock-in measurement to remove the large constant offset from the interference. The technique is characterized by measuring the phase and excited state dynamics of the dye malachite green at the water/air interface. The key attributes of the technique are that the observed signal is directly proportional to sample concentration, in contrast to the quadratic dependence from non-phase sensitive SHG, and that the real and imaginary parts of the 2nd order non-linear susceptibility can be determined independently. We show that the method is highly sensitive and can provide high quality excited state dynamics in short data acquisition times.
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Our current protocol in treating open long-bone fractures includes early administration of intravenous antibiotics and surgery on a scheduled trauma list. This represents a change from a previous protocol where treatment as soon as possible after injury was carried out. This review reports the infection rates in the period 6 years after the start of this protocol. Two hundred and twenty open long-bone fractures were reviewed. Data collected included time of administration of antibiotics, time to theatre and seniority of surgeon involved. The patients were followed up until clinical or radiological union occurred or until a secondary procedure for non-union or infection was performed. Clinical, radiological and haematological signs of infection were documented. If present, infection was classified as deep or superficial. Surgical debridement was performed within 6 h of injury in 45 % of cases and after 6 h in 55 % of cases. Overall infection rates were 11 and 15.7 %, respectively (p = 0.49). The overall deep infection rate was 4.3 %. There was also no statistically significant difference in the subgroups of deep (p = 0.46) and superficial (p = 0.78) infection. Intravenous antibiotics were administered within 3 h of injury in 80 % of cases and after 3 h in 20 % of cases. The infection rates were 14 and 12.5 %, respectively (p = 1.0). There was no statistically significant difference in the subgroups of deep (p = 0.62) and superficial (p = 0.73) infection. Further statistical analysis did not reveal a significant difference in infection rates for any combination of timing of antibiotics and surgical debridement. Infection rates where the most senior surgeon present was a consultant were 9.5 % as opposed to 16 % with the consultant not present, but this trend was not statistically significant. These results suggest that the change in policy may have contributed to an improvement of the deep infection rate to 4.3 % from the previous figure of 8.5 % although this decrease is not statistically significant. Surgeons may have had concerns that delaying theatre may lead to an increased infection rate, but these results do not substantiate this concern.
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Total internal reflection (TIR) spectroscopy is a widely used technique to study soft matter at interfaces. This tutorial review aims to provide researchers with an overview of the principles, experimental design and applications of TIR spectroscopy to enable them to understand how this class of techniques might be used in their research. It also highlights limitations and pitfalls of TIR techniques, which will assist readers in critically analysing the literature. Techniques covered include attenuated total reflection infrared spectroscopy (ATR-IR), TIR fluorescence, TIR Raman scattering and cavity-enhanced techniques. Other related techniques are briefly described.
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Análise Espectral Raman/métodos , Análise Espectral Raman/instrumentaçãoRESUMO
BACKGROUND: The present study aimed to evaluate and determine the factors that affect short- and long-term outcome following manipulation under anaesthesia (MUA) of patients with adhesive capsulitis. METHODS: Patients recruited from January 1999 to January 2010 were retrospectively analyzed and classified as having primary or secondary adhesive capsulitis. All patients were assessed for range of movement (ROM) and Oxford Shoulder Scores (OSS) before and immediately postoperatively, as well as for OSS more than 1 year post MUA. RESULTS: In total, 295 patients (315 shoulders) were sequentially recruited, and information was collected at baseline, as well as at a mean follow-up of 28 days and 3.6 years. A significant improvement in OSS and ROM was noted 1 month post MUA (p < 0.0001) with females benefiting more than males (p < 0.0025). Long-term follow-up revealed that the improvement in OSS was maintained (p < 0.0001). Secondary adhesive capsulitis significantly reduced the efficacy of MUA as assessed by ROM (p < 0.0001). Other factors (age, initial ROM and OSS, and length of symptoms prior to MUA) did not significantly affect the outcome over the short- or long-term. CONCLUSIONS: The findings of the present study show that all patient groups had a significantly improved ROM and OSS in the short-term with long-term maintenance of improved OSS.
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HYPOTHESIS: Frozen shoulder has a greater incidence, more severe course, and resistance to treatment in patients with diabetes mellitus compared with the general population. We hypothesized that diabetic patients with frozen shoulder undergoing treatment with manipulation under general anaesthesia (MUA) would have the same outcome as patients without diabetes. MATERIALS AND METHODS: We retrospectively analyzed data collected during a 10-year period of referrals for frozen shoulder. In all cases, a standardized MUA protocol was followed once the diagnosis of frozen shoulder in the frozen phase was made; this included an early repeat MUA in individuals with recurrence. We compared outcomes for patients documented as having diabetes with a nondiabetic control group and assessed the effect of insulin dependence and frozen shoulder etiology within the diabetic group. RESULTS: Of a consecutive series of 315 frozen shoulders, 36 patients (39 shoulders) were included in the diabetic group, with 256 patients (274 shoulders) as controls. There was a significant improvement in range of movement and Oxford Shoulder Score (P all <.001), with no difference between diabetic and control groups at early or late follow-up (mean, 41 months). A repeat procedure was required in 36% of diabetic patients compared with 15% of control patients. Recurrence in the diabetic group was influenced by etiology (47% of primary vs 0% of secondary frozen shoulders) and insulin requirement (39% insulin-dependent vs. 31% non-insulin-dependent). CONCLUSION: We provide a strategy for the management of diabetic frozen shoulders using MUA and estimates of success and recurrence rates that may be useful when informing consent.
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Anestesia Geral/métodos , Bursite/terapia , Diabetes Mellitus/fisiopatologia , Manejo da Dor/métodos , Amplitude de Movimento Articular , Articulação do Ombro/fisiopatologia , Adulto , Idoso , Bursite/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Manipulação Ortopédica/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Total internal reflection (TIR) Raman spectroscopy is an experimentally straightforward, surface-sensitive technique for obtaining chemically specific spectroscopic information from a region within approximately 100-200 nm of a surface. While TIR Raman spectroscopy has long been overshadowed by surface-enhanced Raman scattering, with modern instrumentation TIR Raman spectra can be acquired from sub-nm thick films in only a few seconds. In this review, we describe the physical basis of TIR Raman spectroscopy and illustrate the performance of the technique in the diverse fields of surfactant adsorption, liquid crystals, lubrication, polymer films and biological interfaces, including both macroscopic structures such as the surfaces of leaves, and microscopic structures such as lipid bilayers. Progress, and challenges, in using TIR Raman to obtain depth profiles with sub-diffraction resolution are described.
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Análise Espectral Raman/métodos , Tensoativos/análise , Adsorção , Bicamadas Lipídicas/análise , Bicamadas Lipídicas/química , Cristais Líquidos/análise , Cristais Líquidos/química , Lubrificantes/análise , Lubrificantes/química , Polímeros/análise , Polímeros/química , Análise Espectral Raman/instrumentação , Propriedades de Superfície , Tensoativos/químicaRESUMO
Total internal reflection (TIR) Raman spectroscopy has been used to study the kinetics of adsorption, desorption, and displacement of mixed surfactant systems at the silica-water interface. The limited penetration depth of the evanescent wave provides surface sensitivity while the chemical sensitivity of Raman scattering permits the determination of the time-dependent composition of the adsorbed film. Principal component analysis is used to deconvolute the Raman spectra with a time resolution of 2 s and a precision of 5% of a monolayer. Both equilibrium and kinetic measurements are presented for the cetyltrimethylammonium bromide (CTAB)/Triton X-100 system over a range of concentrations and compositions. For a total concentration of 2 mM, the adsorption isotherm shows strong synergistic behavior with the addition of small amounts of CTAB (â¼2% of the total surfactant) doubling the adsorbed amount of Triton X-100. This synergism has a marked influence on the kinetics: for example, when Triton X-100 replaces CTAB, the Triton X-100 surface excess overshoots its equilibrium value and returns only very slowly to equilibrium. For systems above the cmc, the repartitioning of surfactant between micelles and monomers results in unexpected behavior during exchange or rinsing of mixed surfactant solutions. For example, during rinsing, the more rapid diffusion of CTAB away from the surface leads to a local increase in the monomer concentration of Triton X-100, resulting in a temporary spike in the Triton X-100 surface excess. Displacement kinetics of CTAB by TX-100 and vice versa are generally slower than the adsorption or desorption of the pure surfactants but cover a wide range of kinetic time scales, depending on the details of the compositions and concentrations of the initial and final solutions.
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Total internal reflection Raman spectroscopy provides a sensitive probe of surfactants adsorbed at an interface. A visible laser passes through a silica hemisphere and reflects off the flat silica-water interface. An evanescent wave probes â¼100 nm of solution below the surface, and the Raman scattering from this region provides chemically specific information on the molecules present. Here we look at both equilibrium and kinetic aspects of the adsorption of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and the nonionic surfactant Triton X-100 in single-component systems. We use the well-defined wall jet geometry to provide known hydrodynamics for the adsorption process. The well-defined hydrodynamics allows us to model the mass transport of surfactant to the surface which is coupled with a kinetic model consistent with the Frumkin isotherm to produce a complete model of the adsorption process. The fit between this model and the experimental results provides insight into the interactions on the surface.
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BACKGROUND: There is a disparity of availability and cost of drugs in the community for palliative care patients through the Pharmaceutical Benefits Scheme (PBS) compared to those available to inpatients in public hospitals. METHODS: The Joint Therapeutics Committee of the Australian and New Zealand Society of Palliative Medicine, Palliative Care Australia and the Clinical Oncological Society of Australia surveyed palliative care practitioners in Australia to compile a list of drugs they considered essential. RESULTS: Drugs nominated generally had good levels of evidence for use in palliative care, although many practitioners still used some without evidence of benefit. DISCUSSION: We are now working with the Commonwealth Department of Health and Ageing to agree on a list of drugs for specific palliative care indications. As a result, the first ever section in the PBS for a specific patient population has been created. There is a need for high quality studies in palliative care to determine the best drugs to add to the list.
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Tratamento Farmacológico/estatística & dados numéricos , Medicina/estatística & dados numéricos , Cuidados Paliativos/estatística & dados numéricos , Especialização , Adulto , Idoso , Anorexia/tratamento farmacológico , Ansiedade/tratamento farmacológico , Austrália , Constipação Intestinal/tratamento farmacológico , Delírio/tratamento farmacológico , Depressão/tratamento farmacológico , Tratamento Farmacológico/métodos , Dispneia/tratamento farmacológico , Medicina de Família e Comunidade/métodos , Medicina de Família e Comunidade/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Humanos , Pessoa de Meia-Idade , Náusea/tratamento farmacológico , Dor/tratamento farmacológico , Cuidados Paliativos/métodos , Agitação Psicomotora/tratamento farmacológico , Xerostomia/tratamento farmacológicoRESUMO
BACKGROUND: As the English-language literature on prosthetic elbow arthroplasty contains only two comparative studies of implants in contemporary use, to our knowledge, comparisons of prosthetic performance is difficult. An improved knowledge of comparative outcomes would be valuable in guiding implant selection. METHODS: We identified three groups of consecutive patients who had undergone prosthetic elbow arthroplasty with the Souter-Strathclyde, Kudo, or Coonrad-Morrey implant for the treatment of rheumatoid arthritis. There were thirty-three elbows in each group. All procedures were done by or under the supervision of one surgeon. Surviving patients in whom the elbow had not been revised were followed for a mean of sixty-one months after treatment with the Souter-Strathclyde implant, sixty-seven months after treatment with the Kudo implant, and sixty-eight months after treatment with the Coonrad-Morrey implant. Clinical function was assessed on the basis of pain relief and the range of flexion. Survivorship was assessed with use of a life-table method, with revision surgery and radiographic signs of loosening as the end points. RESULTS: The groups were comparable in terms of age, sex, and mean duration of follow-up. All three implant procedures relieved pain. Sustained improvement in the range of flexion was comparable among the three groups, with no implant procedure dramatically changing the fixed flexion deformity and all three improving maximum flexion. Revision surgery was needed because of infection, dislocation, and aseptic loosening. Survival of the Coonrad-Morrey implant was better than that of the other two implants. The five-year survival rates, with revision and radiographic signs of loosening as the end points, were 85% and 81% for the Souter-Strathclyde implant, 93% and 82% for the Kudo implant, and 90% and 86% for the Coonrad-Morrey implant. While radiographic evidence of loosening of the Coonrad-Morrey implants was less common, we noted focal osteolysis adjacent to 16% of these ulnar components and half of these cases progressed to frank loosening. CONCLUSIONS: The clinical function of these implants was similar in terms of pain relief and range of motion. We believe that component linkage with the Coonrad-Morrey implant prevents dislocation without increasing the risk of loosening.
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Artrite Reumatoide/cirurgia , Artroplastia de Substituição/instrumentação , Articulação do Cotovelo/cirurgia , Prótese Articular , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
Spontaneous rupture of the popliteus tendon has not previously been reported. We report the case of a 74-year-old patient, discuss its diagnosis and management, and review the current literature on isolated popliteus lesions. A multi-database electronic literature review suggests that the injury is invariably traumatic and has essentially been reported only in young, active individuals. It should be suspected in a patient with acute lateral knee pain who, on examination, has a hemarthrosis and a stable, possibly locked knee. The diagnosis is readily made using arthroscopy. While both conservative treatment with physiotherapy and open repair have been advocated, we describe a successful outcome of arthroscopic resection in an elderly patient and propose that popliteus injury is not confined to a younger age group. The balance of opinion in the current literature is that acute traumatic rupture in the young patient is managed by primary surgical repair, but successful outcome is also reported with nonoperative treatment.