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1.
Heliyon ; 10(1): e23736, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38268586

RESUMO

The role of higher education in the foreign policy of states has been increasing significantly in order to generate soft power. Nevertheless, the literature on the educational aspect of soft power has yet to be systematically reviewed. Therefore, this systematic review is conducted to delineate and analyze the major studies in the field of international higher education which indicates education as a soft power resource for a country. To identify the multiple and contrary arguments on the topic, this study reviewed 48 peer-reviewed articles published from 2001 to 2022. The data collected from the reviewed papers are organized into five sub-sections outlined in the results sections. The contradictions in the literature are examined within the sub-sections in order to understand the various perspectives on education as a resource of soft power. Through analyzing the data mentioned in the results section, this study provides a framework of the essential conditions to harness education as a soft power resource. Furthermore, this review also suggests prospects for future research in this area.

2.
Isotopes Environ Health Stud ; 59(3): 248-268, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37210706

RESUMO

Rainforests play an important role in hydrological and carbon cycles, both at regional and global scales. They pump large quantities of moisture from the soil to the atmosphere and are major rainfall hotspots of the world. Satellite-observed stable water isotope ratios have played an essential role in determining sources of moisture in the atmosphere. Satellites provide information about the processes involving vapour transport in different zones of the world, identifying sources of rainfall and distinguishing moisture transport in monsoonal systems. This paper focuses on major rainforests of the world (Southern Amazon, Congo and Northeast India) to understand the role of continental evapotranspiration in influencing tropospheric water vapour. We have used satellite measurements of 1H2H16O/1H216O from Atmospheric InfraRed Sounder (AIRS), evapotranspiration (ET), solar-induced fluorescence (SIF), precipitation (P), atmospheric reanalysis-derived moisture flux convergence (MFC) and wind to discern the role of ET in influencing water vapour isotopes. A global map of the correlation between δ2Hv and ET-P flux indicates that densely vegetated regions in the tropics show the highest positive correlation (r > 0.5). Using mixing models and observations of specific humidity and isotopic ratio over these forested regions, we discern the source of moisture in pre-wet and wet seasons.


Assuntos
Atmosfera , Vapor , Isótopos de Oxigênio/análise , Estações do Ano , Gases
3.
J Exp Orthop ; 9(1): 86, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36042122

RESUMO

PURPOSE: The introduction of robotics for total knee arthroplasty (TKA) into the operating theatre is often associated with a learning curve and is potentially associated with additional complications. The purpose of this study was to determine the learning curve of robotic-assisted (RA) TKA within a multi-surgeon team. METHODS: This prospective cohort study included 83 consecutive conventional jig-based TKAs compared with 53 RA TKAs using the Robotic Surgical Assistant (ROSA) system (Zimmer Biomet, Warsaw, Indiana, USA) for knee osteoarthritis performed by three high-volume (> 100 TKA per year) orthopaedic surgeons. Baseline characteristics including age, BMI, sex and pre-operative Kellgren-Lawrence graded and Hip-Knee-Ankle Axis were well-matched between the conventional and RA TKA groups. Cumulative summation (CUSUM) analysis was used to assess learning curves for operative times for each surgeon. Peri-operative and delayed complications (infection, periprosthetic fracture, thromboembolism, and compromised wound healing) and revisions were reviewed. RESULTS: The CUSUM analysis for operative time demonstrated an inflexion point after 5, 6 and 15 cases for each of the three surgeons, or 8.7 cases on average. There were no significant differences (p = 0.53) in operative times between the RA TKA learning (before inflexion point) and proficiency (after inflexion point) phases. Similarly, the operative times of the RA TKA group did not differ significantly (p = 0.92) from the conventional TKA group. There was no discernible learning curve for the accuracy of component planning using the RA TKA system. The average length of post-operative follow-up was 21.3 ± 9.0 months. There was one revision for instability in the conventional TKA group and none in the RA TKA group. There were no significant difference (p > 0.99) in post-operative complication rates between the conventional TKA and RA TKA groups. CONCLUSIONS: The introduction of the RA TKA system was associated with a learning curve for operative time of 8.7 cases. Operative times between the RA TKA and conventional TKA group were similar. The short learning curve implies this RA TKA system can be adopted relatively quickly into a surgical team with minimal risks to patients.

4.
IJID Reg ; 2: 1-7, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35721436

RESUMO

Background: COVID-19 emerged as a global pandemic in 2020, spreading rapidly to most parts of the world. The proportion of infected individuals in a population can be reliably estimated via serosurveillance, making it a valuable tool for planning control measures. Our serosurvey study aimed to investigate SARS-CoV-2 seroprevalence in the urban population of Hyderabad at the end of the first wave of infections. Methods: This cross-sectional survey, conducted in January 2021 and including males and females aged 10 years and above, used multi-stage random sampling. 9363 samples were collected from 30 wards distributed over six zones of Hyderabad, and tested for antibodies against SARS-CoV-2 nucleocapsid antigen. Results: Overall seropositivity was 54.2%, ranging from 50% to 60% in most wards. Highest exposure appeared to be among those aged 30-39 and 50-59 years, with women showing greater seropositivity. Seropositivity increased with family size, with only marginal differences among people with varying levels of education. Seroprevalence was significantly lower among smokers. Only 11% of the survey subjects reported any COVID-19 symptoms, while 17% had appeared for COVID-19 testing. Conclusion: Over half the city's population was infected within a year of onset of the pandemic. However, ∼ 46% of people remained susceptible, contributing to subsequent waves of infection.

5.
Biomedicines ; 9(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34829751

RESUMO

Natural bioactive compounds derived from plant-based products are known for their biological immunomodulatory activities. They possess systemic pleiotropic effects, minimal side effects, and very low toxicities. Plant-based bioactive compounds have tremendous potential as natural therapeutic entities against various disease conditions and act as anti-inflammatory, antioxidant, anti-mutagenic, anti-microbial, anti-viral, anti-tumour, anti-allergic, neuroprotective, and cardioprotective agents. A herbal formulation extract including five biologically active compounds: Apigenin, Quercetin, Betulinic acid, Oleanolic acid, and ß-Sitosterol can impart several immunomodulatory effects. In this review, we systematically present the impact of these compounds on important molecular signaling pathways, including inflammation, immunity, redox metabolism, neuroinflammation, neutropenia, cell growth, apoptosis, and cell cycle. The review corroborates the beneficial effect of these compounds and shows considerable potential to be used as a safer, more cost-effective treatment for several diseases by affecting the major nodal points of various stimulatory pathways.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21260555

RESUMO

BackgroundCOVID-19 emerged as a global pandemic in 2020, rapidly spreading to most parts of the world. The proportion of infected individuals in a population can be reliably estimated via sero-surveillance, making it a valuable tool for planning control measures. We conducted a serosurvey study to investigate SARS-CoV-2 seroprevalence in the urban population of Hyderabad at the end of the first wave of infections. MethodsThe cross-sectional survey conducted in January 2021 included males and females aged 10 years and above, selected by multi-stage random sampling. 9363 samples were collected from 30 wards distributed over 6 zones of Hyderabad and tested for antibodies against SARS-CoV-2 nucleocapsid antigen. ResultsOverall seropositivity was 54.2%, ranging from 50-60% in most wards. Highest exposure appeared to be among 30-39y and 50-59y olds, with women showing greater seropositivity. Seropositivity increased with family size, with only marginal differences among people with varying levels of education. Seroprevalence was significantly lower among smokers. Only 11% of the survey subjects reported any COVID-19 symptoms, while 17% had appeared for Covid testing. ConclusionOver half the citys population was infected within a year of onset of the pandemic. However, [~]46% people were still susceptible, contributing to subsequent waves of infection. Highlights National level serosurveys under-estimate localised prevalence in dense urban areas SARS-CoV-2 seroprevalence in Hyderabad city was 54.2% after the first wave A large proportion of the population remains at risk over a year into the pandemic

7.
Ayu ; 42(2): 93-102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37153067

RESUMO

Background: Achillea millefolium L. is traditionally important medicinal herb used for the treatment of various ailments from the centuries. Recent studies showed its biological activities on hay fever, hepato-biliary disorders, and as appetite enhancing drug. It is also reported to be used for the treatments of skin inflammations, wounds, cuts, and abrasions. Aim: To investigate preliminary pharmacognostical, phytochemical, and molecular parameters of aerial parts of the drug. Materials and methods: A. millefolium was identified and collected from the Himalaya region. The material is properly dried, macro-and microscopic evaluation, phytochemical and molecular studies as per the standard quality control and WHO guidelines. Results: The leaves are pinnately lobed, inflorescence compound corymbose. Nonglandular trichomes are uni-seriate, multicellular, and smooth walled; glandular trichomes are bicellular, present throughout the aerial parts. The endodermis is evident in the stem and leaf mesophyll is equifacial. The partial genome sequence analysis showed similarity toward studied species, which can clearly distinguish it from other species of the genus Achillea. The best chromatographic separation was observed with ascentis express C18, 2.7 µm, 100 mm × 4.6 mm. The flavonoids and phenolic acids have shown maximum absorbance at 330 nm. The system suitability parameters such as theoretical plate, tailing factor, and resolution met the acceptance criteria with United States pharmacopeia (USP). Conclusion: The findings of this study will be helpful for the precise identification of the raw drug of A. millefolium from its closely allied species.

8.
Sci Rep ; 9(1): 18646, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819130

RESUMO

Variations in isotopic composition of water vapor in the atmosphere is an important indicator of the processes within the hydrological cycle. Isotopic signature of water vapor and precipitation can be helpful in partitioning evaporation and transpiration fluxes. It is well known that transpiration from forested regions supplies a significant amount of vapor to the atmosphere in monsoon and post-monsoon seasons. Here, we utilize observations from Tropospheric Emission Spectrometer (TES), Atmospheric Infra-Red Sounder (AIRS) and simulation models to ascertain that transpiration is dominant in the forests of Northeast India (NE) during pre-monsoon season. Our results show an increase in δD of 78.0 ± 7.1‰ and in specific humidity of 3.1 ± 0.2 g kg-1 during the pre-monsoon months of April-May compared to January-February. In the monsoon months of July-August, δD reduces by 53.0 ± 6.5‰ albeit the specific humidity increases by 3.4 ± 0.2 g kg-1. Using joint observations of specific humidity and isotope ratio in lower troposphere, we discern the moisture sources over NE India in pre-monsoon and monsoon seasons and posit the role of transpiration in continental recycling during pre-monsoon season.

9.
Adv Pharmacol Sci ; 2019: 8272850, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863446

RESUMO

The objective of the present study was to evaluate "DXB-2030," a polyherbal combination of Trigonella foenum-graecum, Aloe vera, Sphaeranthus indicus, Nardostachys jatamansi, and Symplocos racemosa extracts in an experimental model of testosterone propionate (TP), induced polycystic ovary syndrome (PCOS) in female rats. Thirty animals were divided into 3 groups of 10 each; group 1 served as normal control; group 2 was administered with TP and served as positive control; along with TP, group 3 was treated with "DXB-2030" at a dose of 100 mg/kg p.o., for 60 days. At the end of the study period, the animals were subjected for the estimation of serum testosterone levels, oral glucose tolerance test (OGTT), weight of the ovaries, estrous cycle, and histopathological evaluation. An in vitro assay on GLUT4 expression was carried out to understand the effect of "DXB-2030" on insulin resistance. Results showed that treatment with "DXB-2030" reversed the TP-induced changes by increasing the GLUT4 expression and decreasing the body weight, testosterone levels, AUC of glucose in OGTT, and the cystic follicles of the ovaries, thus indicating its beneficial effect in PCOS by ameliorating the metabolic dysfunction and reproductive impairment, which are the pathophysiological conditions associated with PCOS. From the results obtained, it can be concluded that "DXB-2030" was effective in the management of experimental PCOS and hence may be recommended in the treatment of PCOS.

10.
Plant Mol Biol ; 95(3): 313-331, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28861701

RESUMO

KEY MESSAGE: Ethylene biosynthesis is regulated in reproductive tissues in response to heat stress in a manner to optimize resource allocation to pollinated fruits with developing seeds. High temperatures during reproductive development are particularly detrimental to crop fruit/seed production. Ethylene plays vital roles in plant development and abiotic stress responses; however, little is known about ethylene's role in reproductive tissues during development under heat stress. We assessed ethylene biosynthesis and signaling regulation within the reproductive and associated tissues of pea during the developmental phase that sets the stage for fruit-set and seed development under normal and heat-stress conditions. The transcript abundance profiles of PsACS [encode enzymes that convert S-adenosyl-L-methionine to 1-aminocyclopropane-1-carboxylic acid (ACC)] and PsACO (encode enzymes that convert ACC to ethylene), and ethylene evolution were developmentally, environmentally, and tissue-specifically regulated in the floral/fruit/pedicel tissues of pea. Higher transcript abundance of PsACS and PsACO in the ovaries, and PsACO in the pedicels was correlated with higher ethylene evolution and ovary senescence and pedicel abscission in fruits that were not pollinated under control temperature conditions. Under heat-stress conditions, up-regulation of ethylene biosynthesis gene expression in pre-pollinated ovaries was also associated with higher ethylene evolution and lower retention of these fruits. Following successful pollination and ovule fertilization, heat-stress modified PsACS and PsACO transcript profiles in a manner that suppressed ovary ethylene evolution. The normal ethylene burst in the stigma/style and petals following pollination was also suppressed by heat-stress. Transcript abundance profiles of ethylene receptor and signaling-related genes acted as qualitative markers of tissue ethylene signaling events. These data support the hypothesis that ethylene biosynthesis is regulated in reproductive tissues in response to heat stress to modulate resource allocation dynamics.


Assuntos
Etilenos/biossíntese , Flores/metabolismo , Frutas/metabolismo , Temperatura Alta , Pisum sativum/metabolismo , Transdução de Sinais , Aminoácidos Cíclicos/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Liases/genética , Liases/metabolismo , Pisum sativum/genética , Pisum sativum/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polinização/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Fatores de Tempo
11.
J Exp Bot ; 68(8): 1885-1894, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28011717

RESUMO

Legume crops are grown throughout the world and provide an excellent food source of digestible protein and starch, as well as dietary fibre, vitamins, minerals, and flavonoids. Fruit and seeds from legumes are also an important source of vegetables for a well-balanced diet. A trend in elevated temperature as a result of climate change increases the risk of a heat stress-induced reduction in legume crop yield. High temperatures during the crop reproductive development phase are particularly detrimental to fruit/seed production because the growth and development of the reproductive tissues are sensitive to small changes in temperature. Hormones are signalling molecules that play important roles in a plant's ability to integrate different environmental inputs and modify their developmental processes to optimize growth, survival, and reproduction. This review focuses on the hormonal regulation of reproductive development and heat stress-induced alteration of this regulation during (i) pollination, (ii) early fruit set, and (iii) seed development that affects fruit/seed yield in legume and other model crops. Further understanding of hormone-regulated reproductive growth under non-stress and heat-stress conditions can aid in trait selection and the development of gene modification strategies and cultural practices to improve heat tolerance in legume crops contributing to improved food security.


Assuntos
Produtos Agrícolas/fisiologia , Fabaceae/fisiologia , Sementes/fisiologia , Estresse Fisiológico/fisiologia , Regulação da Expressão Gênica de Plantas , Temperatura Alta
13.
Rev. bras. anestesiol ; 66(4): 423-425,
Artigo em Inglês | LILACS | ID: lil-787627

RESUMO

Abstract Nephrectomies are usually performed under general anesthesia alone or in combination with regional anesthesia and rarely under regional anesthesia alone. We report the management of a patient with chronic obstructive pulmonary disease with a history of recurrent spontaneous pneumothorax undergoing nephrectomy under regional anesthesia alone.


Resumo Geralmente, as nefrectomias são feitas sob anestesia geral, isoladamente ou em combinação com anestesia regional, e raramente sob anestesia regional sozinha. Relatamos o tratamento de um paciente com doença pulmonar obstrutiva crônica e história de pneumotórax espontâneo recorrente submetido à nefrectomia sob anestesia regional isolada.


Assuntos
Humanos , Masculino , Pneumotórax/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Hidronefrose/cirurgia , Hidronefrose/complicações , Anestesia por Condução/métodos , Nefrectomia/métodos , Recidiva , Rim/cirurgia , Pessoa de Meia-Idade
14.
Rev Bras Anestesiol ; 66(4): 423-5, 2016.
Artigo em Português | MEDLINE | ID: mdl-27343353

RESUMO

Nephrectomies are usually performed under general anesthesia alone or in combination with regional anesthesia and rarely under regional anesthesia alone. We report the management of a patient with chronic obstructive pulmonary disease with a history of recurrent spontaneous pneumothorax undergoing nephrectomy under regional anesthesia alone.

15.
Braz J Anesthesiol ; 66(4): 423-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27343795

RESUMO

Nephrectomies are usually performed under general anesthesia alone or in combination with regional anesthesia and rarely under regional anesthesia alone. We report the management of a patient with chronic obstructive pulmonary disease with a history of recurrent spontaneous pneumothorax undergoing nephrectomy under regional anesthesia alone.


Assuntos
Anestesia por Condução/métodos , Hidronefrose/complicações , Hidronefrose/cirurgia , Nefrectomia/métodos , Pneumotórax/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Humanos , Rim/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva
16.
Anesth Essays Res ; 10(2): 349-55, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27212773

RESUMO

BACKGROUND: Goal of premedication in pediatric anesthesia are relieving pre and postoperative anxiety, good parental separation, and smooth induction of anesthesia. Anxiety can produce aggressive reactions, increased distress, increased postoperative pain and postoperative agitation. The benzodiazepine, midazolam, is the most frequently used premedication in pediatric anesthesia. Midazolam has a number of beneficial effects when used as premedication in children: Sedation, fast onset, and limited duration of action. Though midazolam has a number of beneficial effects, it is far from an ideal premedicant having untoward side effects such as paradoxical reaction, respiratory depression, cognitive impairment, amnesia, and restlessness. Dexmedetomidine is a newer α-2-agonist, which can be used as premedicant. AIMS: To compare the level of sedation, parental separation, mask acceptance, postoperative recovery of intranasal premedication with dexmedetomidine and dexmedetomidine-ketamine combination in pediatric patients. SETTINGS AND DESIGN: Prospective randomized double-blind study. SUBJECTS AND METHODS: After written informed consent from the patient's parents or legal guardian, 54 children of American Society of Anesthesiologists physical status I or II, aged between 1 and 6 years, scheduled to undergo elective minor surgery were enrolled. In group D patient received 1 µg/kg dexmedetomidine intranasally and in group DK received 1 µg/kg dexmedetomidine and 2 mg/kg ketamine intranasally. Patients were assessed every 10 min for the level of sedation, parenteral separation, heart rate, and oxygen saturation by an independent observer. Mask acceptance and postoperative agitation were noted using an appropriate scale. STATISTICAL ANALYSIS USED: Pearson Chi-square analysis to determine differences between two groups with respect to separation anxiety and acceptance of the anesthesia mask. Percentages used to represent frequencies. The level of significance was set at P< 0.05. RESULTS: Acceptable parenteral separation was achieved in 90% of patients 30 min after premedication. Sedation was acceptable in 80% of patients at induction. Good mask acceptance was seen in 60% of patients. The incidence of emergence agitation (EA) was 2%. None of the above parameters was statistically significant between the two groups. CONCLUSIONS: Dexmedetomidine, as premedicant in children provides acceptable parenteral separation. However, mask acceptance in operation room is poor. Combination of dexmedetomidine and ketamine does not increase the success of premedication. Use of dexmedetomidine is associated with decreased EA.

17.
J Am Heart Assoc ; 5(4): e002664, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27101833

RESUMO

BACKGROUND: Early intervention with medical and/or coronary revascularization treatment approaches remains the cornerstone of the management of patients hospitalized with acute myocardial infarction (AMI). However, several patient groups, especially the elderly, are known to delay seeking prompt medical care after onset of AMI-associated symptoms. Current trends, and factors associated with prolonged prehospital delay among elderly patients hospitalized with AMI, are incompletely understood. METHODS AND RESULTS: Data from a population-based study of patients hospitalized at all 11 medical centers in central Massachusetts with a confirmed AMI on a biennial basis between 2001 and 2011 were analyzed. Information about duration of prehospital delay after onset of acute coronary symptoms was abstracted from hospital medical records. In patients 65 years and older, the overall median duration of prehospital delay was 2.0 hours, with corresponding median delays of 2.0, 2.1, and 2.0 hours in those aged 65 to 74 years, 75 to 84 years, and in patients 85 years and older, respectively. There were no significant changes over time in median delay times in each of the age strata examined in both crude and multivariable adjusted analyses. A limited number of patient characteristics were associated with prolonged delay in this patient population. CONCLUSIONS: The results of this community-wide study demonstrate that delay in seeking prompt medical care continues to be a significant problem among elderly patients hospitalized with AMI. The lack of improvement in the timeliness of patients' care-seeking behavior during the years under study remains of considerable clinical and public health concern.


Assuntos
Diagnóstico Tardio/estatística & dados numéricos , Serviços Médicos de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Infarto do Miocárdio/diagnóstico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Massachusetts/epidemiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Fatores de Tempo
18.
Bioresour Technol ; 188: 202-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25739996

RESUMO

Nitrilases constitute an important class of biocatalysts for chiral synthesis. This work was undertaken with the aim to optimize nitrilase production in a host that is well-studied for protein production. Process parameters were optimized for high cell density fermentation, in batch and fed-batch modes, of Escherichia coli BL21 (DE3) expressing Pseudomonas fluorescens nitrilase with a T7 promoter based expression system. Effects of different substrates, temperature and isopropyl ß-D-1-thiogalactopyranoside (IPTG) induction on nitrilase production were studied. Super optimal broth containing glycerol but without an inducer gave best results in batch mode with 32 °C as the optimal temperature. Use of IPTG led to insoluble protein and lower enzyme activity. Optimized fed-batch strategy resulted in significant improvement in specific activity as well as volumetric productivity of the enzyme. On a volumetric basis, the activity improved 40-fold compared to the unoptimized batch process.


Assuntos
Aminoidrolases/biossíntese , Escherichia coli/metabolismo , Fermentação , Glicerol/química , Proteínas Recombinantes/biossíntese , Proteínas de Bactérias/biossíntese , Reatores Biológicos , Carbono/química , Meios de Cultura/metabolismo , Glucose/química , Microbiologia Industrial , Isopropiltiogalactosídeo/química , Plasmídeos/metabolismo , Pseudomonas fluorescens/enzimologia
19.
Proc Inst Mech Eng H ; 229(1): 69-76, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25655956

RESUMO

In contrast to the articulating and taper surfaces of failed total hip replacements, volumetric wear analysis of trunnions is not routinely performed. Metal wear particles from the trunnion may contribute not only to the failures of metal-on-metal total hip replacements but also to all hip replacements utilising metal trunnions. A validation study was performed with the material removed in stages from the trunnions of an Exeter V40 stem, a Corail stem and an Accolade stem to simulate different magnitudes of wear. The material loss from the trunnions was measured both volumetrically with a coordinate measuring machine and gravimetrically with a high-precision balance. A cohort of 28 ex vivo trunnions was also measured using the coordinate measuring machine. The maximum error between the two methods was found to be 0.13 mm(3). This result was comparable with the coordinate measuring machine method for the taper surface (0.2 mm(3)). The ex vivo trunnions had a median wear volume of 0.14mm(3) (range: 0.04-0.28 mm(3)). This is the first study to determine the accuracy of volumetric wear measurements of trunnions by comparing against gravimetric measurements. Volumetric wear analysis of trunnions may provide additional insights into failures of modular total hip prostheses and will be performed routinely at our centre.


Assuntos
Análise de Falha de Equipamento/instrumentação , Análise de Falha de Equipamento/métodos , Colo do Fêmur/fisiologia , Colo do Fêmur/cirurgia , Prótese de Quadril , Humanos , Tamanho da Partícula , Desenho de Prótese , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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