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1.
Can J Diet Pract Res ; 80(4): 190-194, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30907125

RESUMO

Increasingly, patients and their caregivers desire blenderized tube feeding (BTF) as an alternative or adjunct to commercial enteral formula. Although dietitians are central in the care of tube fed patients, they do not necessarily have training or experience with BTF and may therefore find it challenging to manage the nutrition of patients who opt for this enteral nutrition approach. To describe dietitians' perspectives, perceived competence, and education on BTF, a cross-sectional survey was conducted by use of an original questionnaire. Dietitians with the authority to practice enteral nutrition in the province of British Columbia, Canada, were included in the study (n = 715). Of the 221 respondents (31% response rate), 28% reported being knowledgeable about BTF, and 24% reported confidence managing patients on BTF. Few agreed they had the expertise to design, administer, or teach administration of BTF (29%, 15%, and 24%, respectively). In regards to education, 27% of respondents did not have BTF education of any kind, and those with BTF education reported it to be primarily derived from informal sources such as self-directed study and learning from colleagues or patients. These results indicate that among dietitians, formal BTF education is uncommon, and there is limited perceived competence on BTF practice.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Nutrição Enteral/métodos , Nutricionistas/educação , Colúmbia Britânica , Estudos Transversais , Dietética/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Nutricionistas/psicologia , Nutricionistas/estatística & dados numéricos , Inquéritos e Questionários
2.
Can J Anaesth ; 65(7): 797-805, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29582360

RESUMO

PURPOSE: Studies comparing the recently introduced Ambu® AuraGain™ (Auragain) with the LMA® Supreme™ (Supreme) supraglottic airway (SGA) have reported conflicting results regarding differences in oropharyngeal leak pressure (OLP). This randomized-controlled trial investigated the OLP of the Auragain compared with the Supreme in patients undergoing ambulatory surgery. METHODS: Adult patients with a body mass index ≤ 40 kg·m-2 presenting for ambulatory surgery and requiring an SGA were randomized to receive either the Auragain or the Supreme. Anesthesia was induced with lidocaine (1 mg·kg-1), fentanyl (1-2 µg·kg-1), and propofol (2-3 mg·kg-1). The SGA was inserted using a standard technique with the cuff inflated to 60 cmH2O. The groups were compared for the primary outcome of OLP. RESULTS: One hundred sixty-five patients (n = 81, Auragain; n = 84, Supreme) completed the study. Demographics were similar between the groups. The mean (standard deviation [SD]) OLP was significantly higher in the Auragain than in the Supreme group [26.4 (2.8) cmH2O vs 21.6 (3.4) cmH2O, respectively; difference in means (MD), 4.8 cmH2O; 95% confidence interval (CI), 3.9 to 5.8; P < 0.001]. The mean (SD) insertion time was longer in the Auragain than in the Supreme group [13 (4) sec vs 11 (3) sec, respectively; MD, 2 sec; 95% CI, 1 to 3 sec; P < 0.001]. CONCLUSION: In patients undergoing ambulatory anesthesia, the OLP was higher but took longer to insert with the Auragain than with the Supreme. A higher OLP may allow for SGAs to be utilized in a wider range of patients and procedures. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02816463). Registered 28 June 2016.


Assuntos
Manuseio das Vias Aéreas/instrumentação , Procedimentos Cirúrgicos Ambulatórios , Máscaras Laríngeas , Adulto , Idoso , Manuseio das Vias Aéreas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Orofaringe , Pressão
3.
BJU Int ; 118 Suppl 3: 30-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27457972

RESUMO

OBJECTIVES: To evaluate the intermediate outcome of conservative management in patients with biopsy-proven oncocytoma. PATIENTS AND METHODS: Patients with oncocytoma diagnosed on percutaneous core biopsy between January 2000 to December 2014 were identified from the renal biopsy database of a large specialist urologic pathology laboratory. After review of patient clinical records, the study cohort comprised only of patients enrolled in active surveillance. Clinicopathological and follow-up details were reviewed for each case, in particular: type and interval of surveillance imaging, tumour growth, definitive intervention and reason for intervention. Where possible, correlation was made between the final surgical and the initial biopsy specimens. RESULTS: Fifty three patients diagnosed with oncocytoma on core biopsy were initially placed on active surveillance with median follow-up of 34 months (range 6-109). The median age at diagnosis was 65 years (range 20-85) and median tumour size was 30 mm (range 13-87). Mean average tumour growth was 1.4 mm per annum (median 0 mm/year) with the majority (36 of 53, 68%) exhibiting minimal growth (less than 2 mm per annum) or partial regression. Forty seven of the 53 patients remained on active surveillance with no significant progression. Six patients elected to undergo definitive intervention (five surgical excision, one ablation). Renal oncocytoma was confirmed in all five patients who underwent surgical excision of their lesions. CONCLUSIONS: The majority of oncocytomas in this study showed minimal growth rate or regression. Patients with biopsy proven oncocytoma can be conservatively managed with active surveillance.


Assuntos
Adenoma Oxífilo/diagnóstico , Adenoma Oxífilo/terapia , Biópsia com Agulha de Grande Calibre , Neoplasias Renais/diagnóstico , Neoplasias Renais/terapia , Conduta Expectante , Adenoma Oxífilo/mortalidade , Adenoma Oxífilo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Seguimentos , Humanos , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
Nano Lett ; 15(9): 6142-8, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26237131

RESUMO

Carbon nanofibers, CNFs, due to their superior strength, conductivity, flexibility, and durability have great potential as a material resource but still have limited use due to the cost intensive complexities of their synthesis. Herein, we report the high-yield and scalable electrolytic conversion of atmospheric CO2 dissolved in molten carbonates into CNFs. It is demonstrated that the conversion of CO2 → CCNF + O2 can be driven by efficient solar, as well as conventional, energy at inexpensive steel or nickel electrodes. The structure is tuned by controlling the electrolysis conditions, such as the addition of trace transition metals to act as CNF nucleation sites, the addition of zinc as an initiator and the control of current density. A less expensive source of CNFs will facilitate its adoption as a societal resource, and using carbon dioxide as a reactant to generate a value added product such as CNFs provides impetus to consume this greenhouse gas to mitigate climate change.

5.
Int J Nurs Stud ; 157: 104829, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38901123

RESUMO

BACKGROUND: The contemporary model for managing heart failure has been extended to a patient-family caregiver dyadic context. However, the key characteristics of the model that can optimise health outcomes for both patients and caregivers remain to be investigated. OBJECTIVES: This study aimed to identify the effects of dyadic care interventions on the behavioural, health, and health-service utilisation outcomes of patients with heart failure and their family caregivers and to explore how the intervention design characteristics influence these outcomes. DESIGN: This study involved systematic review, meta-analysis, and meta-regression techniques. METHODS: We performed a systematic review and meta-analysis, using 12 databases to identify randomised controlled trials or quasi-experimental studies published in English or Chinese between database inception and 31 December 2022. The considered interventions included those targeting patients with heart failure and their family caregivers to enhance disease management. Data synthesis was performed on various patient- and caregiver-related outcomes. The identified interventions were categorised according to their design characteristics for subgroup analysis. Meta-regression was performed to explore the relationship between care delivery methods and their effectiveness. RESULTS: We identified 48 studies representing 9171 patient-caregiver dyads. Meta-analyses suggested the positive effects of dyadic care interventions on patients' health outcomes [Hedges' g (95 % confidence interval {CI}): heart failure knowledge = 1.0 (0.26, 1.75), p = 0.008; self-care confidence = 0.45 (0.08, 0.83), p = 0.02; self-care maintenance = 1.12 (0.55, 1.70), p < 0.001; self-care management = 1.01 (0.54, 1.49), p < 0.001; anxiety = -0.18 (-0.34, -0.02), p = 0.03; health-related quality of life = 0.30 (0.08, 0.51), p < 0.001; hospital admission (risk ratio {95 % CI}: hospital admission = 0.79 (0.65, 0.97), p = 0.007; and mortality = 0.58 (0.36, 0.93), p = 0.02)]. Dyadic care interventions also improved the caregivers' outcomes [Hedges' g (95 % CI): social support = 0.67 (0.01, 1.32), p = 0.05; perceived burden = -1.43 (-2.27, -0.59), p < 0.001]. Although the design of the identified care interventions was heterogeneous, the core care components included enabling and motivational strategies to improve self-care, measures to promote collaborative coping within the care dyads, and nurse-caregiver collaborative practice. Incorporating the first two core components appeared to enhance the behavioural and health outcomes of the patients, and the addition of the last component reduced readmission. Interventions that engaged both patients and caregivers in care provision, offered access to nurses, and optimised continuity of care led to better patient outcomes. CONCLUSIONS: These findings demonstrate that dyadic care interventions can effectively improve disease management in a family context, resulting in better health outcomes for both patients and caregivers. Additionally, this study provides important insights into the more-effective design characteristics of these interventions. REGISTRATION NUMBER: The review protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews (CRD42022322492).


Assuntos
Cuidadores , Insuficiência Cardíaca , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/enfermagem , Insuficiência Cardíaca/psicologia , Humanos , Cuidadores/psicologia
6.
Phys Chem Chem Phys ; 15(38): 16043-53, 2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-23963374

RESUMO

The purported effects of weak magnetic fields on various biological systems from animal magnetoreception to human health have generated widespread interest and sparked much controversy in the past decade. To date the only well established mechanism by which the rates and yields of chemical reactions are known to be influenced by magnetic fields is the radical pair mechanism, based on the spin-dependent reactivity of radical pairs. A diagnostic test for the operation of the radical pair mechanism was proposed by Henbest et al. [J. Am. Chem. Soc., 2004, 126, 8102] based on the combined effects of weak static magnetic fields and radiofrequency oscillating fields in a reaction yield detected magnetic resonance experiment. Here we investigate the effects on radical pair reactions of applying relatively strong oscillating fields, both parallel and perpendicular to the static field. We demonstrate the importance of understanding the effect of the strength of the radiofrequency oscillating field; our experiments demonstrate that there is an optimal oscillating field strength above which the observed signal decreases in intensity and eventually inverts. We establish the correlation between the onset of this effect and the hyperfine structure of the radicals involved, and identify the existence of 'overtone' type features appearing at multiples of the expected resonance field position.

7.
Cont Lens Anterior Eye ; 46(1): 101745, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35995721

RESUMO

PURPOSE: To investigate the effectiveness of orthokeratology (ortho-k) lenses and corneal changes with increased compression factor for myopia control over a 2-year period. METHODS: Young participants (age: 6-<12 years), with low myopia (0.50-4.00 D) and low astigmatism (≤1.25 D), were recruited and allowed to choose to wear either single-vision spectacles or ortho-k lenses (randomly assigned to compression factor of either 0.75 or 1.75 D). Axial length and cycloplegic refraction were measured at six monthly intervals for two years by a masked examiner. The myopia control effectiveness was determined by axial elongation. RESULTS: A significant number of control (63 %) dropped out, mainly due to concern about myopia progression (58 %). A total of 75 participants (mean age: 9.3 ± 1.0 years; control: n = 11, ortho-k [0.75 D]: n = 29, ortho-k [1.75 D]: n = 35) completed the study. Considering ortho-k groups only, the mean axial elongation of participants wearing ortho-k lenses of conventional compression factor (0.75 D) and increased compression factor (1.75 D) were 0.53 ± 0.29 and 0.35 ± 0.29 mm, respectively, over the 2-year study period. The between-group differences in corneal health were not significant at all visits. CONCLUSION: Participants wearing ortho-k lenses of increased compression factor further slowed axial elongation by 34%, when compared with the conventional compression factor without compromising corneal health. Further investigations are warranted to confirm the potential mechanism of an increased compression factor for improved myopia control effectiveness.


Assuntos
Astigmatismo , Miopia , Procedimentos Ortoceratológicos , Criança , Humanos , Comprimento Axial do Olho , Córnea , Miopia/terapia , Refração Ocular , Testes Visuais
8.
Cont Lens Anterior Eye ; 45(4): 101484, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34303626

RESUMO

PURPOSE: To investigate the repeatability and reproducibility of choroidal thickness measurements using Lenstar images in young myopic children before and after one-month orthokeratology (ortho-k) treatment. METHOD: Ocular biometry of 39 subjects were performed using the Lenstar 900. The first five measurements with maximum differences of 0.02 mm in axial length in the right eyes were saved and used for measurement of choroidal thickness. Subfoveal choroidal thickness were manually measured by identifying the signals from the retinal pigmented epithelium layer and chorioscleral interface. Repeatability was determined by comparing measurements of the same images made by the same observer on two separate occasions (four weeks apart), while reproducibility was calculated by comparing measurements of the same images made by two independent observers. Data was analysed using intra-class correlation coefficients (ICC) and non-parametric Bland and Altman plots. RESULTS: The choroidal peaks could not be identified in all five measurements in all subjects. On average, only 71% subjects had at least four definable images. Compared with the use of fewer than four images, reliability using an average of four definable images improved statistically, but remained clinically unacceptable (>10 µm), although pre- and post-ortho-k ICC values were good to excellent for repeatability (0.867 and 0.975, respectively) and excellent and good for reproducibility (0.959 and 0.868, respectively). Non-parametric pre- and post-ortho-k limits of agreement (2.5% and 97.5% percentiles) obtained were -45.8 to 79.3 µm and -30.3 to 9.5 µm, respectively for repeatability, and -29.0 to 33.5 µm and -21.8 to 70.0 µm, respectively for reproducibility. CONCLUSION: Choroidal thickness measurements using the Lenstar did not show good reliability, despite the high ICC values, non-parametric Bland and Altman plots demonstrated a wide variability of measurement errors. Any changes in subfoveal choroidal thickness, measured by Lenstar, of <80 µm may not represent real changes.


Assuntos
Miopia , Tomografia de Coerência Óptica , Biometria , Criança , Corioide/diagnóstico por imagem , Humanos , Miopia/terapia , Reprodutibilidade dos Testes , Tomografia de Coerência Óptica/métodos
9.
Artigo em Inglês | MEDLINE | ID: mdl-34497978

RESUMO

C/C++/OpenCL-based high-level synthesis (HLS) becomes more and more popular for field-programmable gate array (FPGA) accelerators in many application domains in recent years, thanks to its competitive quality of results (QoR) and short development cycles compared with the traditional register-transfer level design approach. Yet, limited by the sequential C semantics, it remains challenging to adopt the same highly productive high-level programming approach in many other application domains, where coarse-grained tasks run in parallel and communicate with each other at a fine-grained level. While current HLS tools do support task-parallel programs, the productivity is greatly limited ① in the code development cycle due to the poor programmability, ② in the correctness verification cycle due to restricted software simulation, and ③ in the QoR tuning cycle due to slow code generation. Such limited productivity often defeats the purpose of HLS and hinder programmers from adopting HLS for task-parallel FPGA accelerators. In this paper, we extend the HLS C++ language and present a fully automated framework with programmer-friendly interfaces, unconstrained software simulation, and fast hierarchical code generation to overcome these limitations and demonstrate how task-parallel programs can be productively supported in HLS. Experimental results based on a wide range of real-world task-parallel programs show that, on average, the lines of kernel and host code are reduced by 22% and 51%, respectively, which considerably improves the programmability. The correctness verification and the iterative QoR tuning cycles are both greatly shortened by 3.2× and 6.8×, respectively. Our work is open-source at https://github.com/UCLA-VAST/tapa/.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33467770

RESUMO

HIV self-testing (HIVST) with online real-time counseling (HIVST-online) is an evidence-based intervention to increase HIV testing coverage and to ensure linkage to care for men who have sex with men (MSM). A community-based organization (CBO) recruited 122 MSM who had ever used HIVST-online (ever-users) and another 228 new-users from multiple sources and promoted HIVST-online. A free oral fluid-based HIVST kit was sent to all the participants by mail. Experienced HIVST administrators implemented HIVST-online by providing real-time instruction, standard-of-care pre-test and post-test counseling via live-chat application. The number of HIVST-online sessions performed was documented by the administrators. The post-test evaluation was conducted 6 months after the pre-test survey. At month 6, 63.1% of ever-users and 40.4% of new-users received HIVST-online. Taking other types of HIV testing into account, 79.4% of ever-users and 58.6% of new-users being followed up at month 6 received any HIV testing during the project period. Ever-users were more likely to receive HIVST-online and any HIV testing as compared to new-users. Four HIVST-online users were screened to be HIV positive and linked to the treatment. The process evaluation of HIVST-online was positive. Implementation of HIVST-online was helpful to improve HIV testing coverage and repeated HIV testing among Chinese MSM. A larger scale implementation should be considered.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Aconselhamento , Infecções por HIV/diagnóstico , Teste de HIV , Homossexualidade Masculina , Hong Kong , Humanos , Masculino , Programas de Rastreamento , Autoteste
11.
FPGA ; 2021: 81-92, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33851145

RESUMO

Despite an increasing adoption of high-level synthesis (HLS) for its design productivity advantages, there remains a significant gap in the achievable frequency between an HLS design and a handcrafted RTL one. A key factor that limits the timing quality of the HLS outputs is the difficulty in accurately estimating the interconnect delay at the HLS level. This problem becomes even worse when large HLS designs are implemented on the latest multi-die FPGAs. To tackle this challenge, we propose AutoBridge, an automated framework that couples a coarse-grained floorplanning step with pipelining during HLS compilation. First, our approach provides HLS with a view on the global physical layout of the design, allowing HLS to more easily identify and pipeline the long wires, especially those crossing the die boundaries. Second, by exploiting the flexibility of HLS pipelining, the floorplanner is able to distribute the design logic across multiple dies on the FPGA device without degrading clock frequency. This prevents the placer from aggressively packing the logic on a single die which often results in local routing congestion that eventually degrades timing. Since pipelining may introduce additional latency, we further present analysis and algorithms to ensure the added latency will not compromise the overall throughput. AutoBridge can be integrated into the existing CAD toolflow for Xilinx FPGAs. In our experiments with a total of 43 design configurations, we improve the average frequency from 147 MHz to 297 MHz (a 102% improvement) with no loss of throughput and a negligible change in resource utilization. Notably, in 16 experiments we make the originally unroutable designs achieve 274 MHz on average. The tool is available at https://github.com/Licheng-Guo/AutoBridge.

12.
BMJ Open ; 10(12): e034844, 2020 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371012

RESUMO

OBJECTIVES: To assess the association of fluoroquinolone use with tendon ruptures compared with no fluoroquinolone and that of the four most commonly prescribed non-fluoroquinolone antibiotics in the USA. DESIGN: Retrospective observational study. SETTING: US seniors enrolled in the federal old-age, survivor's insurance programme. PARTICIPANTS: 1 009 925 Medicare fee-for-service beneficiaries and their inpatient, outpatient, prescription drug records were used. INTERVENTIONS: Seven oral antibiotics, fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin) and amoxicillin, amoxicillin-clavulanate, azithromycin and cephalexin. PRIMARY AND SECONDARY OUTCOME MEASURES: All tendon ruptures combined, and three types of tendon ruptures by anatomic site, Achilles tendon rupture, rupture of rotator cuff and other tendon ruptures occurred in 2007-2016. RESULTS: Of three fluoroquinolones, only levofloxacin exhibited a significant increased risk of tendon ruptures-16% (HR=1.16; 95% CI 1.06 to 1.28), and 120% (HR=2.20; 95% CI 1.50 to 3.24) for rotator cuff and Achilles tendon rupture, respectively, in the ≤30 days window. Ciprofloxacin (HR=0.96; 95% CI 0.89 to 1.03) and moxifloxacin (HR=0.59; 95% CI 0.37 to 0.93) exhibited no increased risk of tendon ruptures combined.Among the non-fluoroquinolone antibiotics, cephalexin exhibited increased risk of combined tendon ruptures (HR=1.31; 95% CI 1.22 to 1.41) and modest to large risks across all anatomic rupture sites (HRs 1.19-1.93) at ≤30 days window. Notably, the risk of levofloxacin never exceeded the risk of the non-fluoroquinolone, cephalexin in any comparison. CONCLUSIONS: In our study, fluoroquinolones as a class were not associated with the increased risk of tendon ruptures. Neither ciprofloxacin nor moxifloxacin exhibited any risk for tendon ruptures. Levofloxacin did exhibit significant increased risk. Cephalexin with no reported effect on metalloprotease activity had an equal or greater risk than levofloxacin; so we question whether metalloprotease activity has any relevance to observed associations with tendon rupture. Confounding by indication bias may be more relevant and should be given more consideration as explanation for significant associations in observational studies of tendon rupture.


Assuntos
Antibacterianos , Fluoroquinolonas , Idoso , Antibacterianos/efeitos adversos , Fluoroquinolonas/efeitos adversos , Humanos , Medicare , Estudos Retrospectivos , Ruptura , Tendões , Estados Unidos/epidemiologia
13.
Mar Pollut Bull ; 154: 111116, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32319930

RESUMO

The degree of organotin compounds (OTCs), including dibutyltin, tributyltin, triphenyltin and dioctyltin, contamination in seafood purchased in 2017 and 2018 from Hong Kong market was studied. Edible portions of 341 seafood samples, including fish, crustaceans and molluscs, were used for analysis by gas chromatograph coupled to an inductively coupled plasma mass spectrometry (GC-ICP/MS). The method detection limits and quantification limits of OTCs were below or equal to 0.25 and 1.0 µg Sn kg-1 respectively. Triphenyltin accounted for the majority amongst other OTCs and was detected in 53% of samples. In general, mean total OTCs levels of fish (24 µg Sn kg-1) were higher than crustaceans (14 µg Sn kg-1) and molluscs (15 µg Sn kg-1). The highest detected levels of triphenyltin, tributyltin, dibutyltin and dioctyltin were found to be 480, 24, 4.5 and 0.89 µg Sn kg-1 in a mangrove snapper, noodle fish, coral clam and giant grouper respectively.


Assuntos
Compostos Orgânicos de Estanho , Animais , Crustáceos , Peixes , Hong Kong , Alimentos Marinhos/análise
14.
Invest Ophthalmol Vis Sci ; 61(2): 22, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32068792

RESUMO

Purpose: This retrospective longitudinal study aimed to examine the relationship between ocular higher-order aberrations (HOA) and axial eye growth in young myopic children undergoing orthokeratology (ortho-k) treatment. Methods: Axial length and ocular HOA, measured under cycloplegia annually over a 2-year period from the right eyes of myopic children, who previously completed ortho-k clinical trials, were retrieved. Linear mixed model analyses were applied to determine the association between ocular HOA, other known confounding variables (age, sex, and refractive error), and axial eye growth. Results: Data from 103 subjects were analyzed. The root-mean square (RMS) values of total ocular HOA (third to sixth orders combined), spherical (\({\rm{Z}}_4^0\) and \({\rm{Z}}_6^0\) combined), and comatic (\({\rm{Z}}_3^{ - 1}\), \({\rm{Z}}_3^1\), \({\rm{Z}}_5^{ - 1}\), and \({\rm{Z}}_5^1\) combined) aberrations increased by approximately 3, 9, and 2 times, respectively, after 2 years of ortho-k treatment. After adjusting for age, sex, and refractive error, higher RMS values of total HOA and spherical aberrations were associated with both longer axial length and slower axial elongation (all P < 0.01). For individual Zernike term coefficients, a higher level of positive spherical aberration (\({\rm{Z}}_4^0\)) was also associated with longer axial length and slower axial elongation (both P < 0.01), after adjusting for baseline HOA. Conclusions: Ortho-k for myopia control significantly increases the Zernike coefficients and therefore the RMS values for a range of total ocular HOA terms or metrics in children. These findings suggest the potential role of HOA, particularly spherical aberration, as the possible mechanism of slowing axial elongation in ortho-k treatment.


Assuntos
Comprimento Axial do Olho/fisiologia , Aberrações de Frente de Onda da Córnea/fisiopatologia , Miopia/fisiopatologia , Miopia/cirurgia , Procedimentos Ortoceratológicos , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos
15.
BMJ Open Ophthalmol ; 5(1): e000345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32420450

RESUMO

OBJECTIVE: To present the study design and the baseline data of a prospective cohort study investigating the safety, refractive correction and effectiveness of myopia control in subjects fitted with orthokeratology (ortho-k) lenses of different compression factors. METHODS AND ANALYSIS: This study is a 2-year longitudinal, double-masked, partially randomised study. Myopic children aged between 6 and 10 years are recruited and they may choose to participate in either the ortho-k or spectacle-wearing group. Subjects in the ortho-k group are randomly assigned to wear ortho-k lenses of either conventional compression factor (CCF, 0.75 D) or increased compression factor (ICF, 1.75 D). For the ortho-k subjects, the time and between-group effects within the first month of lens wear were analysed. RESULTS: Sixty-nine ortho-k subjects (CCF: 34; ICF: 35) and 30 control subjects were recruited. There were no significant differences in baseline demographic data among the three groups of subjects (p>0.19). At the 1-month visit, the first fit success rates were 97% and 100% in the CCF and ICF ortho-k group, respectively. A higher percentage of ICF subjects could achieve full correction (CCF: 88.2%; ICF: 94.3%). The change in axial length was significantly higher in the ICF group (CCF, 0.003 mm; ICF, -0.031 mm) (p<0.05). No significant between-group differences in daytime vision or in the coverage and depth of corneal staining between the two ortho-k groups (p>0.05) were observed at any visit. CONCLUSION: ICF did not compromise the corneal integrity and the lens centration within the first month of lens wear. The preliminary performance of ortho-k lenses with ICF of 1.00D shows that it was safe to be used in the longer term for the investigation of myopia control. TRIAL REGISTRATION NUMBER: NCT02643342.

16.
Clin Exp Optom ; 103(1): 123-128, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31264269

RESUMO

BACKGROUND: To investigate the influence of compression factor upon changes in ocular higher-order aberrations (HOAs) in young myopic children undergoing orthokeratology treatment. METHODS: Subjects aged between six and < 11 years, with low myopia (0.50-4.00 D inclusive), low astigmatism (≤ 1.25 D), and anisometropia (≤ 1.00 D), were randomly assigned to wear orthokeratology lenses of different compression factors in each eye (one eye 0.75 D and the fellow eye 1.75 D). HOAs were measured weekly over one month of lens wear. Wavefront analysis was conducted over a 5-mm pupil using a sixth order Zernike polynomial expansion. Linear mixed models were used to examine the individual Zernike co-efficients and specific root-mean-square (RMS) error (spherical, comatic, total HOAs) metrics and their changes between the two eyes during the study period. RESULTS: Twenty-eight myopic (mean manifest spherical equivalent refraction: -2.10 ± 0.58 D) children (median [range] age: 9.3 [7.8-11.0] years) were analysed. Significant interocular differences in HOAs at baseline were observed for Z6-6 and Z6-4 only (both p < 0.05). During the lens wear period, eyes fitted with the increased compression factor showed greater changes in primary spherical aberration ( Z40 , p = 0.04) and RMS values for spherical and total HOAs (both p < 0.01). Considering data from both eyes together, after adjusting for the paired nature of the data, some other Zernike terms ( Z31 and Z60 , both p < 0.01) and the RMS value of comatic aberrations (p < 0.001) significantly increased after one month of orthokeratology treatment. The increase in primary spherical aberration ( Z40 ) was positively correlated with the reduction in spherical equivalent refractive error, but only in eyes fitted with the increased compression factor (r = 0.69, p < 0.001). CONCLUSIONS: Increasing the orthokeratology compression factor by 1.00 D significantly altered some HOAs, particularly spherical aberration. Given the association between positive spherical aberration and eye growth in children, further research investigating the influence of orthokeratology compression factor on axial eye growth is warranted.


Assuntos
Lentes de Contato , Aberrações de Frente de Onda da Córnea/fisiopatologia , Miopia/terapia , Procedimentos Ortoceratológicos , Criança , Topografia da Córnea , Método Duplo-Cego , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia
17.
Cont Lens Anterior Eye ; 43(1): 65-72, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31704093

RESUMO

PURPOSE: To evaluate changes in refractive and corneal responses in myopic children wearing orthokeratology (ortho-k) lenses with conventional compression factor (CCF, 0.75 D) and increased compression factor (ICF, 1.75 D). METHODS: This was a double-blind self-controlled study. Subjects were randomly fitted with CCF in one eye and ICF in the fellow eye. Weekly monitoring of refraction, visual acuity (VA), external ocular health, and corneal responses were performed over one month of lens wear and after discontinuation of lens wear until stabilization was achieved. RESULTS: Twenty-five subjects, aged 9.4 ±â€¯1.0 years, completed one-month lens wear, of whom 23 completed the washout period. The first fit success rates for CCF and ICF were 93% and 96%, respectively. Myopia, unaided VA, central corneal thickness, anterior corneal curvatures (K), apical power (AP), and corneal resistance factor (CRF) all changed significantly during the study period (P <  0.003). Between-eye difference was significant only for myopia reduction (P =  0.001). About 4% and 8% of ICF and CCF eyes were under-corrected. The attempted target was achieved in about 80% of CCF and 60% of ICF eyes at week 4. At the end of the washout period (3 weeks), myopia, K, and AP were significantly different compared to baseline (P <  0.001). CONCLUSION: Increasing the compression factor did not affect the first fit success rate and external ocular health, but did allow faster correction of refractive error within one month of lens wear. Further investigation is warranted to investigate the long-term effects of ICF on myopia control compared to CCF.


Assuntos
Lentes de Contato , Córnea/fisiopatologia , Miopia/terapia , Procedimentos Ortoceratológicos , Refração Ocular/fisiologia , Criança , Topografia da Córnea , Método Duplo-Cego , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Acuidade Visual/fisiologia
18.
Inorg Chem ; 48(2): 708-18, 2009 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-19099443

RESUMO

A series of luminescent cyclometalated iridium(III) polypyridine indole complexes, [Ir(N--C)(2)(N--N)](PF(6)) (HN--C = 2-phenylpyridine (Hppy), N--N = 4-((2-(indol-3-yl)ethyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine (bpy-ind) (1a), N--N = 4-((5-((2-(indol-3-yl)ethyl)aminocarbonyl)pentyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine (bpy-C6-ind) (1b); HN--C = 7,8-benzoquinoline (Hbzq), N--N = bpy-ind (2a), N--N = bpy-C6-ind (2b); and HN--C = 2-phenylquinoline (Hpq), N--N = bpy-ind (3a), N--N = bpy-C6-ind (3b)), have been synthesized, characterized, and their photophysical and electrochemical properties and lipophilicity investigated. Photoexcitation of the complexes in fluid solutions at 298 K and in alcohol glass at 77 K resulted in intense and long-lived luminescence (lambda(em) = 540-616 nm, tau(o) = 0.13-5.15 mus). The emission of the complexes has been assigned to a triplet metal-to-ligand charge-transfer ((3)MLCT) (dpi(Ir) --> pi*(N--N)) excited state, probably with some mixing of triplet intraligand ((3)IL) (pi --> pi*) (pq) character for complexes 3a,b. Electrochemical measurements revealed that all the complexes showed an irreversible indole oxidation wave at ca. +1.1 V versus SCE, a quasi-reversible iridium(IV/III) couple at ca. +1.3 V, and a reversible diimine reduction couple at ca. -1.3 V. The interactions of these complexes with an indole-binding protein, bovine serum albumin (BSA), have been studied by emission titrations, and the K(a) values are on the order of 10(4) M(-1). Additionally, the cytotoxicity of the complexes toward human cervix epithelioid carcinoma (HeLa) cells has been examined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. The IC(50) values of the complexes ranged from 1.1 to 6.3 microM, which are significantly smaller than that of cisplatin (30.7 microM) under the same experimental conditions. Furthermore, the cellular uptake of the complexes has been investigated by flow cytometry and laser-scanning confocal microscopy. The microscopy images indicated that complex 3a was localized in the perinuclear region upon interiorization. Temperature-dependence experiments suggested that the internalization of the complex was an energy-requiring process such as endocytosis. This has been confirmed by cellular-uptake experiments involving the luminescent conjugates Ir-BSA and Ir-TF (TF = holo-transferrin), which were prepared by conjugation of the proteins with the complex [Ir(pq)(2)(phen-NCS)](PF(6)) (phen-NCS = 5-isothiocyanato-1,10-phenanthroline).


Assuntos
Indóis/química , Irídio/química , Luminescência , Compostos Organometálicos/síntese química , Compostos Organometálicos/metabolismo , Polímeros/química , Piridinas/química , Absorção , Animais , Bovinos , Eletroquímica , Elétrons , Citometria de Fluxo , Células HeLa , Humanos , Microscopia Confocal , Compostos Organometálicos/química , Compostos Organometálicos/toxicidade , Ligação Proteica , Soroalbumina Bovina/metabolismo , Titulometria
19.
Support Care Cancer ; 17(10): 1311-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19184123

RESUMO

OBJECTIVES: This is a retrospective observational study evaluating hypersensitivity reactions captured by an electronic medical record (EMR) system for weekly paclitaxel infusions. MATERIALS AND METHODS: The study evaluates the demographics, co-morbidities, premedications, chemotherapy agents, and postmedications of patients reporting a hypersensitivity reaction to weekly infusions of paclitaxel at a major cancer center, from June 2006 to December 2007. Data were analyzed using descriptive statistics and logistic regression. P values <0.05 were considered significant. RESULTS: There were 51 hypersensitivity reactions in 36 patients during this time period that were documented in the allergy section of the EMR. Reactions occurred in patients with an average age of 55 years (SD = 10.77); 47 (92%) of the reactions occurred in females, and 42 (82%) of the reactions occurred with orders on the breast medical/surgical service. Thirty-two (63%) reactions occurred with either the first or second dose of weekly paclitaxel infusion. The most common premedication was dexamethasone (50 infusions), followed by diphenhydramine (18 infusions), and cimetidine (14 infusions). Thirty-three (65%) infusions had only one premedication. Postreaction, 41 (80%) cases had diphenhydramine and 30 (59%) cases had hydrocortisone administered prior to restarting the infusion. Logistic regression analysis did not indicate any relationship between history of previous allergies, hypertension, coronary disease, or chronic obstructive pulmonary disease and the number of premedications. CONCLUSIONS: The results indicate that there is substantial variability in the type and number of premedications utilized in the management of paclitaxel hypersensitivity reactions. Interventions are needed to decrease the rate of hypersensitivity reactions from weekly paclitaxel infusions.


Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos/uso terapêutico , Hipersensibilidade a Drogas/epidemiologia , Paclitaxel/efeitos adversos , Pré-Medicação/efeitos adversos , Esquema de Medicação , Hipersensibilidade a Drogas/tratamento farmacológico , Hipersensibilidade a Drogas/etiologia , Humanos , Infusões Intravenosas/efeitos adversos , Modelos Logísticos , Sistemas Computadorizados de Registros Médicos , Estudos Retrospectivos
20.
Transl Vis Sci Technol ; 8(4): 9, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360614

RESUMO

PURPOSE: To determine the influence of compression factor upon changes in axial length and choroidal thickness during and following orthokeratology treatment. METHODS: Orthokeratology lenses of different compression factors (one eye with 0.75 D and the fellow eye with 1.75 D) were randomly assigned to 28 subjects (median [range] age: 9.3 [7.8-11.0] years). Ocular biometrics were measured weekly for 1 month of lens wear and after lens cessation until the refraction stabilized (mean duration: 2.8 ± 0.4 weeks). Changes between eyes, and the associations between axial shortening and choroidal thickening with other ocular biometrics were analyzed. RESULTS: There were no significant between-eye differences in the changes of ocular biometrics (all P > 0.05). After adjusting for paired-eye data, axial length initially decreased by 26 ± 41 µm (P = 0.03) at week 1, then gradually returned to its original length. An approximate antiphase relationship of choroidal thickness (mean change: 9 ± 12 µm, P < 0.001) with axial length was observed. A significant rebound in axial length, but not choroidal thickness, occurred during the cessation period. Central corneal thinning and choroidal thickening accounted for 70% of initial axial shortening. CONCLUSIONS: Increasing the compression factor by 1.00 D did not affect changes in ocular biometrics in short-term orthokeratology. Significant axial shortening and choroidal thickening were observed during early treatment period. Axial shortening could not be entirely explained by central corneal thinning and choroidal thickening, which warrants further investigation. TRANSLATIONAL RELEVANCE: Initial axial shortening in orthokeratology is transient and therefore axial length remains useful for long-term monitoring of axial elongation in children.

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