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1.
Int J Pharm ; 635: 122788, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36863544

RESUMO

The incidence of fungal pulmonary infections is known to be on the increase, and yet there is an alarming gap in terms of marketed antifungal therapies that are available for pulmonary administration. Amphotericin B (AmB) is a highly efficient broad-spectrum antifungal only marketed as an intravenous formulation. Based on the lack of effective antifungal and antiparasitic pulmonary treatments, the aim of this study was to develop a carbohydrate-based AmB dry powder inhaler (DPI) formulation, prepared by spray drying. Amorphous AmB microparticles were developed by combining 39.7 % AmB with 39.7 % γ-cyclodextrin, 8.1 % mannose and 12.5 % leucine. An increase in the mannose concentration from 8.1 to 29.8 %, led to partial drug crystallisation. Both formulations showed good in vitro lung deposition characteristics (80 % FPF < 5 µm and MMAD < 3 µm) at different air flow rates (60 and 30 L/min) when used with a DPI, but also during nebulisation upon reconstitution in water.


Assuntos
Anfotericina B , Pneumonia , Humanos , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Inaladores de Pó Seco , Manose , Pulmão , Macrófagos Alveolares , Administração por Inalação , Tamanho da Partícula , Pós/farmacologia , Aerossóis e Gotículas Respiratórios
2.
Foot (Edinb) ; 53: 101924, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36037775

RESUMO

PURPOSE: To validate a new classification system for bespoke thermoplastic ankle foot orthoses (AFOs). METHODS: Inter- and intra-observer reliability study. A classification system based on the design and function of AFOs was created. Sixty-three independent observers classified thirty-six photographs of different AFOs, according to the proposed classification system via an online questionnaire. Approximately two weeks later, the same AFOs were classified again by fifty-three of the same participants. All participants were health care professionals, researchers, or technicians with experience in referring for, prescribing, fitting, reviewing, researching or manufacturing AFOs. RESULTS: The mean inter- and intra-observer agreement Fleiss' kappa was 0.932 and 0.944, respectively. 98.3% of participants reported that the classification system was very easy or moderately easy to use, with 85.7% reporting they would use the classification system. 90.5% of participants reported that the proposed AFO classification system was clear, with 84% stating it was useful. CONCLUSION: The proposed classification system for bespoke thermoplastic AFOs, has an excellent inter- and intra-observer agreement. It will reduce the ambiguity of the description of the type of AFOs used in clinical practice and research. Furthermore, it makes reproducible comparisons between groups possible, which are essential for future evaluations of evidence-based orthotic care.


Assuntos
Órtoses do Pé , Humanos , Articulação do Tornozelo , Reprodutibilidade dos Testes , Fenômenos Biomecânicos , , Marcha
3.
Diabetes Res Clin Pract ; 187: 109865, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35398144

RESUMO

AIMS: Literature indicates that altered plantar loading in people with diabetes could trigger changes in plantar soft tissue biomechanics which, in turn, could affect the risk for ulceration. To stimulate more research in this area, this study uses in vivo testing to investigate the link between plantar loading and tissue hardness. METHODS: Tissue hardness and plantar pressure distribution were measured for six plantar areas in 39 people with diabetes and peripheral neuropathy. RESULTS: Spearman correlation analysis revealed that increased pressure time integral at the 1st metatarsal-head region (r = -0.354, n = 39, P = 0.027) or at the heel (r = -0.378, n = 39, P = 0.018) was associated with reduced hardness in the same regions. After accounting for confounding parameters, generalised estimating equations analysis also showed that 10% increase in pressure time integral at the heel was associated with ≈ 1 unit reduction in hardness in the same region. CONCLUSIONS: For the first time, this study reveals that people with diabetes and neuropathy who tend to load their feet more heavily also tend to have plantar soft tissues with lower hardness. The observed difference in tissue hardness is likely to affect the tissue's vulnerability to overload injury. More research will be needed to explore the implications of the observed association for the risk of ulceration.


Assuntos
Diabetes Mellitus , Pé Diabético , Doenças do Sistema Nervoso Periférico , , Dureza , Calcanhar , Humanos
5.
Drug Dev Ind Pharm ; 47(2): 292-301, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33496638

RESUMO

OBJECTIVE: The focus of this study was to investigate the possibility of producing ibuprofen-nicotinamide (IBU-NIC) and ibuprofen-isonicotinamide (IBU-INA) cocrystal-containing granules, using a one-step fluidized bed dryer granulation manufacturing process, and evaluate their mechanical properties. SIGNIFICANCE: Pharmaceutical cocrystals represent a suitable strategy to improve properties of active pharmaceutical ingredients (APIs), such as solubility and processability. Ibuprofen (IBU) is a small molecule API which can form cocrystals with different coformers, including NIC and INA. An improvement in mechanical properties for IBU-NIC cocrystals relative to IBU was previously reported but, to date, the formulation of IBU cocrystals in a solid dosage form has not been investigated. METHODS: In situ cocrystallization and granulation were achieved concurrently by processing in a lab-scale fluidized bed granulator following a design of experiment (DoE) approach using a two-level factorial design with both process and formulation variables. Solid-state, micrometric, dissolution, and mechanical (tabletability) characteristics of granules were assessed post-processing. RESULTS: Granules containing cocrystals were successfully prepared for 11 of 16 DoE runs. Parameters with a significant effect on granule drug loading, flow function, porosity, and size could be identified from the DoE model. Process yield was increased by using a high inlet temperature at high solution feed rate. To avoid the formation of sticky particles, caking and over-wetting of the powder during the process, the utilization of high inlet temperature, low API + coformer:filler ratio, low API concentration in solution and low solution feed rate were suggested by the model. CONCLUSION: The multivariable model developed enables accurate optimization of the granulation process for IBU cocrystals.


Assuntos
Excipientes , Ibuprofeno , Porosidade , Pós , Solubilidade
6.
Foot (Edinb) ; 43: 101660, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32179372

RESUMO

STUDY DESIGN: Case series. BACKGROUND: AFOs are a commonly prescribed medical device given to children with cerebral palsy (CP) in an attempt to improve their gait. The current literature is equivocal on the effects AFOs have on the gait of children with CP. The vast majority of AFOs issued are not subject to AFO-FC tuning. There are emerging studies investigating the effects tuning AFO-FCs has on the gait of children with CP. However, the research is limited, and there is a lack of quantitative data. OBJECTIVE: To compare the kinematics of tuned versus non-tuned gait in children with CP. METHODS: Gait analysis assessment of five children aged between 7-11 years with a diagnosis of CP (one hemiplegic and four diplegic participants, two female, three male, with a Gross Motor Functional Classification System (GMFCS) of 2) at a Gait Analysis Laboratory. RESULTS: In comparison to barefoot and non-tuned gait, walking with a tuned AFO-FC produced improvements in several key gait parameters. Including hip flexion and extension, posterior pelvic tilt and knee extension. Results also indicated that the type of gait pattern demonstrated by the participant affected the outcomes of tuning. CONCLUSIONS: Tuning the AFO-FC of children with CP has the potential to improve hip function, pelvic function, knee extension in stance phase and knee flexion during swing phase and that a non-tuned AFO-FC can potentially decrease hip function, posterior pelvic tilt and increase knee extension. CLINICAL RELEVANCE: Whilst AFO-FC tuning has been recommended for routine clinical practice, there still remains a paucity of research on the kinematic effects of using a tuned AFO-FC compared to a non-tuned. This paper provides a comparison of kinematics on children with CP, during barefoot, non-tuned and tuned AFO-FC walking with a view to inform clinical practice.


Assuntos
Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/reabilitação , Órtoses do Pé , Marcha/fisiologia , Sapatos , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Amplitude de Movimento Articular/fisiologia
7.
Foot (Edinb) ; 43: 101655, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32086139

RESUMO

STUDY DESIGN: Pilot study. BACKGROUND: Ankle foot orthoses (AFOs) and footwear combination (FC) is a commonly prescribed medical device given to children with cerebral palsy (CP) in an attempt to improve their gait. Biomechanically optimising the AFO-FC often requires large adaptations to the sole of the user's footwear. There is currently a dearth of literature regarding the user's perception of wearing biomechanically optimised AFOs and adapted footwear and whether their perception affects their adherence to orthotic treatment. OBJECTIVE: This study aimed to investigate perception and adherence to wearing an AFO and FC the participants were asked to wear as part of their orthotic prescription. In particular, whether the visibly modified footwear affected the user's adherence to the orthotic treatment. METHODS: Questionnaire devised for the purpose of this study. RESULTS: All five participants responded to the questionnaire; reporting a high number of positive responses in relation to function, including; an improvement in the way they walked, improved balance and fewer falls. Conversely, there was a high level of negative responses regarding aesthetics, with all participants reporting they did not like the cosmesis of their AFO-FCs. They were conscious that the modification to their footwear was noticeable and therefore different from their peers, yet they adhered to the treatment and in some cases increased the wearing time. CONCLUSIONS: This pilot set of questions indicated that cosmesis is an important factor for children who wear AFOs and adapted footwear. It can be concluded that the impact of the adapted AFO-FC on the participants' function outweighed their opinion on the cosmesis of the device. CLINICAL RELEVANCE: It is vital to understand how orthotic prescriptions affect user adherence. Orthotic prescriptions which are not utilised by the user result in a failed treatment intervention, regardless of the scientific application underpinning them.


Assuntos
Paralisia Cerebral/psicologia , Paralisia Cerebral/reabilitação , Órtoses do Pé , Cooperação do Paciente/psicologia , Autoimagem , Braquetes , Criança , Feminino , Humanos , Masculino , Projetos Piloto , Sapatos , Contenções , Inquéritos e Questionários
8.
Int J Pharm ; 566: 476-487, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31085253

RESUMO

Currently in the pharmaceutical industry, continuous manufacturing is an area of significant interest. In particular, hot-melt extrusion (HME) offers many advantages and has been shown to significantly reduce the number of processing steps relative to a conventional product manufacturing line. To control product quality during HME without process interruption, integration of inline analytical technology is critical. Vibrational spectroscopy (Raman, NIR and FT-IR) is often employed and used for real-time measurements because of the non-destructive and rapid nature of these analytical techniques. However, the establishment of reliable Process Analytical Technology (PAT) tools for HME of thermolabile drugs is challenging. Indeed, the Raman effect is inherently weak and might be subject to interference. Moreover, during HME, heating and photodecomposition can occur and disrupt spectra acquisition. The aim of this research article was to explore the use of inline Raman spectroscopy to characterise a thermolabile drug, ramipril (RMP), during continuous HME processing. Offline measurements by HPLC, LC-MS and Raman spectroscopy were used to characterise RMP and its main degradation product, ramipril-diketopiperazine (RMP-DKP, impurity K). A set of HME experiments together with inline Raman spectroscopic analyses were performed. The feasibility of implementing inline Raman spectroscopic analysis to quantify the level of RMP and RMP-DKP in the extrudate was addressed. Two regions in the Raman spectrum were selected to differentiate RMP and RMP-DKP. When regions were combined, a principle component analysis (PCA) model defined by these two main components (PC 1 = 50.1% and PC 2 = 45%) was established. Using HPLC analyses, we were able to confirm that the PC 1 score was attributed to the level of RMP-DKP, and the PC 2 score was related to the RMP drug content. Investigation of the PCA scatterplot indicated that HME processing temperature was not the only factor causing RMP degradation. Additionally, the plasticiser content, feeding speed and screw rotating speed contributed to RMP degradation during HME processing.


Assuntos
Tecnologia de Extrusão por Fusão a Quente , Controle de Qualidade , Análise Espectral Raman/métodos , Cromatografia Líquida de Alta Pressão , Citratos/química , Combinação de Medicamentos , Plastificantes/química , Ácidos Polimetacrílicos/química , Ramipril/química
9.
Int J Pharm ; 562: 228-240, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30849470

RESUMO

The present study evaluates the effect of L-leucine concentration and operating parameters of a laboratory spray dryer on characteristics of trehalose dry powders, with the goal of optimizing production of these powders for inhaled drug delivery. Trehalose/L-leucine mixtures were spray dried from aqueous solution using a laboratory spray dryer. A factorial design of experiment (DoE) was undertaken and process parameters adjusted were: inlet temperature, gas flow rate, feed solution flow rate (pump setting), aspiration setting and L-leucine concentration. Resulting powders were characterised in terms of particle size, yield, residual moisture content, and glass transition temperature. Particle size was mainly influenced by gas flow rate, whereas product yield and residual moisture content were found to be primarily affected by inlet temperature and spray solution feed rate respectively. Interactions between a number of different process parameters were elucidated, as were relationships between different responses. The leucine mass ratio influenced the physical stability of powders against environmental humidity, and a high leucine concentration (30% w/w) protected amorphous trehalose from moisture induced crystallization. High weight ratio of leucine in the formulation, however, negatively impacted the aerosol performance. Thus, in terms of L-leucine inclusion in a formulation designed for pulmonary delivery, a balance needs to be found between physical stability and deposition characteristics.


Assuntos
Composição de Medicamentos/métodos , Leucina/química , Trealose/química , Administração por Inalação , Aerossóis , Dessecação , Desenho de Fármacos
10.
Mol Pharm ; 16(5): 1827-1838, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30702301

RESUMO

Hyperlipidaemia is considered as one of the main risk factors associated with cardiovascular diseases (CVDs). Among different lipid-lowering agents used to manage hyperlipidaemia, statins are highly prescribed for management of hyperlipidaemia with simvastatin being one of the most common. Simvastatin is susceptible to extensive metabolism by CYP450 3A4 and 3A5, which are expressed both in the liver and the gastrointestinal tract. Nevertheless, the localization of these enzymes is site-dependent with lower concentration at the distal/proximal regions of the small intestine/colon. In addition to statins, medications such as antihypertensive agents and anticoagulants are introduced as adjuvants, for the treatment of cardiovascular disease. The aim of this study was to design a bilayer delivery system capable of delivering biphasic release of simvastatin and aspirin, within a fixed dose combination. A delayed release platform based on a combination of anionic polymers prepared using hot-melt extrusion was developed to delay the release of simvastatin. An optimized formulation tested for dissolution performance clearly demonstrated an ability to delay the release of simvastatin. In addition, an immediate release layer based on Kollidon VA64 was successfully developed to deliver aspirin. Both formulations were then manufactured as a bilayer drug delivery system (tablets and coextrudates), and the release performance was examined. On the basis of the obtained results, these formulations may be used as a platform for delivering a wide range of medications in a biphasic manner.


Assuntos
Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/tratamento farmacológico , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Desenho de Fármacos , Hiperlipidemias/complicações , Hiperlipidemias/tratamento farmacológico , Aspirina/administração & dosagem , Aspirina/química , Formas de Dosagem , Combinação de Medicamentos , Liberação Controlada de Fármacos , Tecnologia de Extrusão por Fusão a Quente/métodos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Polietilenoglicóis/química , Polivinil/química , Pirrolidinas/química , Sinvastatina/administração & dosagem , Sinvastatina/química , Solubilidade , Compostos de Vinila/química
11.
Int J Pharm ; 545(1-2): 183-196, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29730176

RESUMO

The purpose of this work was to investigate the application of different advanced continuous processing techniques (hot melt extrusion and spray drying) to the production of fixed-dose combination (FDC) monolithic systems comprising of hydrochlorothiazide and ramipril for the treatment of hypertension. Identical FDC formulations were manufactured by the two different methods and were characterised using powder X-ray diffraction (PXRD) and modulated differential scanning calorimetry (mDSC). Drug dissolution rates were investigated using a Wood's apparatus, while physical stability was assessed on storage under controlled temperature and humidity conditions. Interestingly both drugs were transformed into their amorphous forms when spray dried, however, hydrochlorothiazide was determined, by PXRD, to be partially crystalline when hot melt extruded with either polymer carrier (Kollidon® VA 64 or Soluplus®). Hot melt extrusion was found to result in significant degradation of ramipril, however, this could be mitigated by the inclusion of the plasticizer, polyethylene glycol 3350, in the formulation and appropriate adjustment of processing temperature. The results of intrinsic dissolution rate studies showed that hot-melt extruded samples were found to release both drugs faster than identical formulations produced via spray drying. However, the differences were attributable to the surface roughness of the compressed discs in the Wood's apparatus, rather than solid state differences between samples. After a 60-day stability study spray dried samples exhibited a greater physical stability than the equivalent hot melt extruded samples.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/química , Diuréticos/química , Temperatura Alta , Hidroclorotiazida/química , Ramipril/química , Tecnologia Farmacêutica/métodos , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Portadores de Fármacos , Combinação de Medicamentos , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Plastificantes/química , Polietilenoglicóis/química , Polivinil/química , Difração de Pó , Pirrolidinas/química , Solubilidade , Propriedades de Superfície , Compostos de Vinila/química
13.
Genes Brain Behav ; 16(7): 709-724, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28523735

RESUMO

Opioid abuse in the United States has reached epidemic proportions, with treatment admissions and deaths associated with prescription opioid abuse quadrupling over the past 10 years. Although genetics are theorized to contribute substantially to inter-individual variability in the development, severity and treatment outcomes of opioid abuse/addiction, little direct preclinical study has focused on the behavioral genetics of prescription opioid reinforcement and drug-taking. Herein, we employed different 129 substrains of mice currently available from The Jackson Laboratory (129S1/SvlmJ, 129X1/SvJ, 129S4/SvJaeJ and 129P3/J) as a model system of genetic variation and assayed mice for oral opioid intake and reinforcement, as well as behavioral and somatic signs of dependence. All substrains exhibited a dose-dependent increase in oral oxycodone and heroin preference and intake under limited-access procedures and all, but 129S1/SvlmJ mice, exhibited oxycodone reinforcement. Relative to the other substrains, 129P3/J mice exhibited higher heroin and oxycodone intake. While 129X1/SvJ exhibited the highest anxiety-like behavior during natural opioid withdrawal, somatic and behavior signs of precipitated withdrawal were most robust in 129P3/J mice. These results demonstrate the feasibility and relative sensitivity of our oral opioid self-administration procedures for detecting substrain differences in drug reinforcement/intake among 129 mice, of relevance to the identification of genetic variants contributing to high vs. low oxycodone reinforcement and intake.


Assuntos
Variação Genética , Transtornos Relacionados ao Uso de Opioides/genética , Reforço Psicológico , Síndrome de Abstinência a Substâncias/genética , Analgésicos Opioides/efeitos adversos , Animais , Fentanila/efeitos adversos , Heroína/efeitos adversos , Masculino , Camundongos , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Oxicodona/efeitos adversos
14.
Org Biomol Chem ; 13(42): 10527-31, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26337398

RESUMO

A late stage Diels-Alder reaction is used to prepare a mixture of JBIR-22, a natural product from the Equisetin family of tetramic acids, and one of its diastereomers. This is achieved in just 8 steps from pyruvate. The success of the late stage DA approach is discussed in the context of the biosynthesis of JBIR-22 (and perhaps related natural products).


Assuntos
Pirrolidinonas/síntese química , Tetra-Hidronaftalenos/síntese química , Ciclização , Estrutura Molecular , Naftalenos/química , Pirrolidinonas/química , Estereoisomerismo , Tetra-Hidronaftalenos/química
15.
Med Hypotheses ; 81(5): 789-91, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24055096

RESUMO

Using the Interactive Autism Network Research Database, the Autistic Spectrum Disorder concordance rates for twins and non-twin siblings were calculated. For males, females and both genders together, the concordance rate for dizygotic twins is approximately twice that of non-twin siblings. We also determined that the concordance rate for non-twin siblings decreases as the interval between pregnancies increases. Our results appear to indicate that the uterine environment may contribute to autism concordance rates.


Assuntos
Intervalo entre Nascimentos/estatística & dados numéricos , Transtornos Globais do Desenvolvimento Infantil/epidemiologia , Doenças em Gêmeos/epidemiologia , Irmãos , Gêmeos , Útero/fisiologia , Feminino , Humanos , Masculino , Modelos Biológicos
16.
J Dairy Sci ; 96(3): 1905-14, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23357013

RESUMO

This study investigated conception rates and other reproductive outcomes achieved with artificial insemination (AI) of nulliparous Holstein heifers using sexed and conventional semen in a commercial Australian dairy herd in central western New South Wales from January 2004 to April 2009. Retrospective data from on-farm records of 9,870 inseminations of 4,456 heifers were analyzed using several mixed models to assess the effect of temperature and humidity surrounding breeding, insemination sire, artificial insemination technician, service number, and heifer weight and age at breeding on reproductive traits (conception rates, sex ratios, gestation length, and abortion and stillbirth rates). Semen was used from 15 sexed sires and 41 unsexed sires. Sexed semen was primarily used at first and second service. Empirical conception rates of 31.6 and 39.6% were achieved for sexed and unsexed semen respectively, whereas model-based predictions were lower, at 21.3 and 32.1%. Conception rates were significantly affected by insemination sire, sex-sorting, heifer age at breeding, temperature and humidity surrounding breeding, service number, and AI technician. Sexed semen yielded 86% heifers, compared with 48% for conventional semen. Significant predictors of calf sex included semen sexing, gestation length, and insemination sire. Twinning rate was high, at 3.6% for both semen types, and gestation length and heifer weight at breeding were significant predictors of twinning. Abortion rates for sexed and unsexed conceptions were similar at 6.1 and 6.5%, respectively, and were affected by heifer age at breeding. Stillbirth rate was affected by calf sex, twinning, gestation length, and AI technician; semen sorting, age at breeding, and temperature and humidity were marginally significant predictors. No abnormalities were observed in the development of offspring, except for a marginally higher stillbirth rate for sexed calves, a finding that needs further investigation. Many variables influence the breeding outcomes associated with the application of sex-sorted sperm on commercial dairy farms. Recognition and management of these variables will increase the economic return from the investment in sex-sorted sperm.


Assuntos
Inseminação Artificial/veterinária , Sêmen , Pré-Seleção do Sexo/veterinária , Fatores Etários , Animais , Bovinos , Indústria de Laticínios/métodos , Feminino , Fertilização , Abrigo para Animais , Inseminação Artificial/métodos , Inseminação Artificial/estatística & dados numéricos , Masculino , Gravidez , Gravidez Múltipla/estatística & dados numéricos , Pré-Seleção do Sexo/métodos , Pré-Seleção do Sexo/estatística & dados numéricos
17.
Stud Health Technol Inform ; 176: 104-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22744469

RESUMO

There are assumptions that leg length discrepancy (LLD) may cause low back pain by creating pelvis obliquity and lumbar scoliosis. Although individuals with LLD develop compensatory movements in the lower limbs and pelvis during walking, few investigations have attempted to identify kinematic variables of the upper body. This study aims to gain an understanding of how simulated LLD influences three-dimensional motion of the pelvis and spine. Seven male participants were required to walk barefoot at a preferred speed. Three LLD conditions (1, 2, and 3cm) were simulated using modified pieces of high density EVA attached to the right foot. An optoelectronic motion analysis system was used to record kinematic data of the pelvis and spine (lumbar, lower and upper thoracic segments) for each condition. Differences in range of motion and patterns of movement for the pelvis and lumbar spine were minimal between barefoot and LLD conditions. These observations could be attributed to various kinematic compensatory strategies within the lower limbs which require further in-depth investigation.


Assuntos
Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Marcha , Desigualdade de Membros Inferiores/complicações , Desigualdade de Membros Inferiores/fisiopatologia , Vértebras Lombares/fisiopatologia , Pelve/fisiopatologia , Adulto , Humanos , Amplitude de Movimento Articular
18.
Stud Health Technol Inform ; 176: 151-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22744479

RESUMO

Optoelectronic motion capture technology is a useful tool in the quantitative dynamic assessment of the spine. In a clinical setting this may help gain a further understanding of underlining musculoskeletal pathology. It is therefore important that accurate measurements are made to allow data to be comparable across various investigations. This report outlines a new multi-segment spinal model and its validation. A mechanical model consisting of an upper thoracic (UT), lower thoracic and lumbar segment was developed allowing for range of motion assessment. An electrogoniometer and torsiometer were attached to the model to provide a control measurement. The UT segment was chosen for analysis and static trials were collected at angles ranging from 2-45°. Kinematic data was captured using an optoelectronic motion capture system. Software computed angles corresponded well with the control measure. While highlighting the differences in the estimation of angles between software platforms, this study emphasizes the need for the clear description and understanding of the kinematic model used.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Movimento/fisiologia , Postura/fisiologia , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/fisiologia , Humanos , Interpretação de Imagem Assistida por Computador/instrumentação , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Foot (Edinb) ; 22(1): 10-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21944945

RESUMO

BACKGROUND: Previous research has found that ankle joint equinus can lead to foot pathologies. Calf stretching exercises are a common treatment prescription; however, no dynamic quantitative data on its effectiveness is available. OBJECTIVE: To investigate the effect of calf muscle stretching on ankle joint dorsiflexion and subsequent changes within dynamic forefoot peak plantar pressures (PPP), force and temporal parameters. METHOD: Thirteen runners with ankle joint equinus were required to perform calf muscle stretching twice a day (morning and evening) on a Flexeramp. Measurements were collected on day 1, week 4 and week 8. A repeated measures ANOVA with Bonferroni-adjusted post hoc comparisons was used to assess differences across the three data collection sessions. RESULTS: Findings indicated that the calf stretching program increased ankle joint dorsiflexion significantly (from 5° to 16°, p≤0.05). The adaptive kinetics brought about by the increased ankle joint range of motion included significantly increased forefoot PPP and maximum force during stance phase but decreased time between heel contact and heel lift and total stance phase time. CONCLUSION: The calf stretching programme used in this study was found to increase ankle joint dorsiflexion and hence can be used for first line conservative management of ankle equinus.


Assuntos
Articulação do Tornozelo/fisiologia , Exercícios de Alongamento Muscular/métodos , Músculo Esquelético/fisiologia , Fenômenos Fisiológicos Musculoesqueléticos , Amplitude de Movimento Articular/fisiologia , Adulto , Artrometria Articular/métodos , Fenômenos Biomecânicos , Feminino , Seguimentos , Humanos , Masculino , Pressão
20.
Med Phys ; 39(6Part4): 3633, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28519500

RESUMO

PURPOSE: For almost four decades bead and wire ramps have been used in the evaluation of slice width as part of QA testing for CT scanners. While each of these approaches have been recognized and accepted as reliable, in this paper we investigate the differences, advantages and limitations of these tools. Moreover, we study the effect of varying the field of view (FOV) and focal spot size. METHODS: The Catphan® 700 phantom includes two pairs of bead ramps (coarse and fine) and a pair of wire ramps in the same module providing an ideal setting for comparing bead ramps and wire ramps. The phantom was scanned using three devices from two different manufacturers. The data set consisted of 428 slices of 0.5,1,2,4,8 and 10 mm thickness. For the study of FOV and focal spot, 512 slices from the Catphan® 600 were acquired. All images were analyzed using Image Owl Catphan® QA software. RESULTS: For 0.5mm slices, bead ramps gave more accurate and precise (lower variance) estimation of the thickness than wire ramps. For 2-4 mm slices, the two approaches performed on equal terms while for the thickest slices (8 and 10mm), the wires gave more precise results. For thin slices, a small FOV (100mm) gave better results and lower spread than a large FOV (240mm). Finally, a small focal spot gave significantly better results than a large one using wire ramps for 0.5 and 1mm slices. CONCLUSIONS: For measuring thin slices, the use of bead ramps, with adequately small FOV and a small focal spot should be advised. For measuring thick slices, wire ramps will give less variability although bead ramps give equally accurate results on average. Funding provided by The Phantom Laboratory, Incorporated and Image Owl, Incorporated.

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