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1.
J Ment Health ; : 1-8, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38845178

ABSTRACT

BACKGROUND: Mental illnesses and mental health challenges have become increasingly pervasive among Chinese university students. However, the utilization rate of mental health services is low among students. AIMS: We aimed to explore Chinese university students' help-seeking behaviors to understand how they deal with mental health challenges and use the results to inform the development of effective mental health promotion initiatives. METHODS: In this study, we conducted 13 focus group interviews with students in six universities in Jinan, China, including 91 (62%) female students and 56 (38%) male students. We drew on the Theory of Planned Behaviors to guide our thematic analysis to gain a contextual understanding of participants' accounts on help-seeking. RESULTS: Our results have depicted the help-seeking patterns of Chinese university students and show that there are four major behaviors which are self-reliance, seeking support from peers and families, seeking professional support, and accessing virtual mental health care. CONCLUSION: Results from this study can be used to inform the development of mental health literacy programming for students in universities that share similar contexts, and the study has also opened up a new space for using qualitative approaches to study mental health needs and access to care in diverse populations.

2.
Pediatr Surg Int ; 39(1): 262, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37668756

ABSTRACT

INTRODUCTION: Central venous catheter (CVC) placement is commonly performed in children. We aim to develop simple formulas to predict CVC intravascular length to minimise radiation exposure associated with the procedure. METHODS: 124 paediatric patients who received tunnelled neck CVCs and subsequent CT thorax at Hong Kong Children's Hospital from January 2020 to July 2022 were reviewed retrospectively. Formula development cohorts were subdivided by insertion sites-9 right external jugular vein (REJV), 41 right internal jugular vein (RIJV), 14 left external jugular vein (LEJV), 10 left internal jugular vein (LIJV). Using measurements from CT by two radiologists, formulas predicting the CVC intravascular length based on height and insertion sites were developed using a linear regression model. These formulas were tested with validation cohorts (10 randomly selected cases in REJV and RIJV groups respectively). Validation cohorts were not available for LEJV and LIJV groups due to small sample sizes. RESULT: The goodness-of-fit (R^2) of all formulas are above 0.8. In the validation cohorts, the REJV formula was predictive of intravascular CVC length within 1 cm in 70% of CVC with mean absolute difference of 0.63 cm (SD 0.48 cm), and the RIJV formula was predictive of intravascular CVC length within 1 cm in 80% of CVC with mean absolute difference of 0.67 cm (SD 0.53 cm). CONCLUSION: Intravascular CVC length can be estimated using simple formulas based on height and insertion sites. Further prospective validation of the LEJV and LIJV formulas is needed.


Subject(s)
Central Venous Catheters , Humans , Child , Retrospective Studies , Brachiocephalic Veins , Hospitals, Pediatric , Jugular Veins/diagnostic imaging
4.
Nano Lett ; 23(5): 1717-1725, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36821385

ABSTRACT

Magnetic particle imaging (MPI) is a sensitive, high-contrast tracer modality that images superparamagnetic iron oxide nanoparticles, enabling radiation-free theranostic imaging. MPI resolution is currently limited by scanner and particle constraints. Recent tracers have experimentally shown 10× resolution and signal improvements with dramatically sharper M-H curves. Experiments show a dependence on interparticle interactions, conforming to literature definitions of superferromagnetism. We thus call our tracers superferromagnetic iron oxide nanoparticles (SFMIOs). While SFMIOs provide excellent signal and resolution, they exhibit hysteresis with non-negligible remanence and coercivity. We provide the first quantitative measurements of SFMIO remanence decay and reformation using a novel multiecho pulse sequence. We characterize MPI scanning with remanence decay and coercivity and describe an SNR-optimized pulse sequence for SFMIOs under human electromagnetic safety limitations. The resolution from SFMIOs could enable clinical MPI with 10× reduced scanner selection fields, reducing hardware costs by up to 100×.

5.
Clin Radiol ; 77(5): 319-325, 2022 05.
Article in English | MEDLINE | ID: mdl-35000764

ABSTRACT

Anomalies in number and location may occur during splenic development. This review aims to offer a brief overview of splenic function and embryology and a detailed account of the imaging appearances using different imaging techniques of the normal spleen and various congenital splenic anomalies including (1) abnormal viscero-atrial situs, (2) splenogonadal fusion, (3) intrapancreatic accessory spleen, (4) wandering spleen, and (5) splenosis. Emphasis is placed on the salient features that help radiologists recognise important associations (e.g., asplenia/polysplenia in situs abnormalities), avoid diagnostic pitfalls (e.g., mistaking intrapancreatic accessory spleen as pancreatic neoplasms), and potential complications (e.g., acute torsion in wandering spleen). The correct identification of the said anomalies from more sinister causes, such as malignancies, are essential, where early intervention is necessary.


Subject(s)
Heterotaxy Syndrome , Splenic Diseases , Wandering Spleen , Heterotaxy Syndrome/diagnostic imaging , Humans , Multimodal Imaging , Splenic Diseases/diagnostic imaging
6.
Small Methods ; 5(11): e2100796, 2021 11.
Article in English | MEDLINE | ID: mdl-34927972

ABSTRACT

Magnetic nanoparticles have many advantages in medicine such as their use in non-invasive imaging as a Magnetic Particle Imaging (MPI) tracer or Magnetic Resonance Imaging contrast agent, the ability to be externally shifted or actuated and externally excited to generate heat or release drugs for therapy. Existing nanoparticles have a gentle sigmoidal magnetization response that limits resolution and sensitivity. Here it is shown that superferromagnetic iron oxide nanoparticle chains (SFMIOs) achieve an ideal step-like magnetization response to improve both image resolution & SNR by more than tenfold over conventional MPI. The underlying mechanism relies on dynamic magnetization with square-like hysteresis loops in response to 20 kHz, 15 kAm-1 MPI excitation, with nanoparticles assembling into a chain under an applied magnetic field. Experimental data shows a "1D avalanche" dipole reversal of every nanoparticle in the chain when the applied field overcomes the dynamic coercive threshold of dipole-dipole fields from adjacent nanoparticles in the chain. Intense inductive signal is produced from this event resulting in a sharp signal peak. Novel MPI imaging strategies are demonstrated to harness this behavior towards order-of-magnitude medical image improvements. SFMIOs can provide a breakthrough in noninvasive imaging of cancer, pulmonary embolism, gastrointestinal bleeds, stroke, and inflammation imaging.


Subject(s)
Magnetite Nanoparticles/chemistry , Mesenchymal Stem Cells/cytology , Cells, Cultured , Humans , Magnetic Resonance Imaging , Mesenchymal Stem Cells/chemistry
7.
J Otolaryngol Head Neck Surg ; 50(1): 59, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34670607

ABSTRACT

BACKGROUND: During the early part of the COVID-19 pandemic, the Canadian Society of Otolaryngology - Head & Neck Surgery (CSO-HNS) task force published recommendations on performance of tracheotomy. Since then, our understanding of the virus has evolved with ongoing intensive research efforts. New literature has helped us better understand various aspects including patient outcomes and health care worker (HCW) risks associated with tracheotomy during the COVID-19 pandemic. Accordingly, the task force has re-evaluated and revised some of the previous recommendations. MAIN BODY: Based on recent evidence, a negative reverse transcription polymerase chain reaction (RT-PCR) COVID-19 swab status is no longer the main deciding factor in the timing of tracheotomy. Instead, tracheotomy may be considered as soon as COVID-19 swab positive patients are greater than 20 days beyond initial symptoms and 2 weeks of mechanical ventilation. Furthermore, both open and percutaneous surgical techniques may be considered with both techniques showing similar safety and outcome profiles. Additional recommendations with discussion of current evidence are presented. CONCLUSION: These revised recommendations apply new evidence in optimizing patient and health care system outcomes as well as minimizing risks of COVID-19 transmission during aerosol-generating tracheotomy procedures. As previously noted, additional evidence may lead to further evolution of these and other similar recommendations.


Subject(s)
COVID-19/prevention & control , Infection Control , Otolaryngology , Tracheotomy , COVID-19/diagnosis , COVID-19/transmission , Canada , Critical Care , Humans , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Patient Selection , Practice Guidelines as Topic
11.
Nanotheranostics ; 5(2): 240-255, 2021.
Article in English | MEDLINE | ID: mdl-33614400

ABSTRACT

White blood cells (WBCs) are a key component of the mammalian immune system and play an essential role in surveillance, defense, and adaptation against foreign pathogens. Apart from their roles in the active combat of infection and the development of adaptive immunity, immune cells are also involved in tumor development and metastasis. Antibody-based therapeutics have been developed to regulate (i.e. selectively activate or inhibit immune function) and harness immune cells to fight malignancy. Alternatively, non-invasive tracking of WBC distribution can diagnose inflammation, infection, fevers of unknown origin (FUOs), and cancer. Magnetic Particle Imaging (MPI) is a non-invasive, non-radioactive, and sensitive medical imaging technique that uses safe superparamagnetic iron oxide nanoparticles (SPIOs) as tracers. MPI has previously been shown to track therapeutic stem cells for over 87 days with a ~200 cell detection limit. In the current work, we utilized antibody-conjugated SPIOs specific to neutrophils for in situ labeling, and non-invasive and radiation-free tracking of these inflammatory cells to sites of infection and inflammation in an in vivo murine model of lipopolysaccharide-induced myositis. MPI showed sensitive detection of inflammation with a contrast-to-noise ratio of ~8-13.


Subject(s)
Cell Tracking/methods , Magnetics , Neutrophils/cytology , Humans
12.
Curr Oncol ; 27(5): e467-e477, 2020 10.
Article in English | MEDLINE | ID: mdl-33173386

ABSTRACT

Background: Head-and-neck cancers (hncs) often present at an advanced stage, leading to poor outcomes. Late presentation might be attributable to patient delays (reluctance to seek treatment, for instance) or provider delays (misdiagnosis, prolonged wait time for consultation, for example). The objective of the present study was to examine the length and cause of such delays in a Canadian universal health care setting. Methods: Patients presenting for the first time to the hnc multidisciplinary team (mdt) with a biopsy-proven hnc were recruited to this study. Patients completed a survey querying initial symptom presentation, their previous medical appointments, and length of time between appointments. Clinical and demographic data were collected for all patients. Results: The average time for patients to have their first appointment at the mdt clinic was 15.1 months, consisting of 3.9 months for patients to see a health care provider (hcp) for the first time since symptom onset and 10.7 months from first hcp appointment to the mdt clinic. Patients saw an average of 3 hcps before the mdt clinic visit (range: 1-7). No significant differences in time to presentation were found based on stage at presentation or anatomic site. Conclusions: At our tertiary care cancer centre, a patient's clinical pathway to being seen at the mdt clinic shows significant delays, particularly in the time from the first hcp visit to mdt referral. Possible methods to mitigate delay include education about hnc for patients and providers alike, and a more streamlined referral system.


Subject(s)
Delayed Diagnosis , Head and Neck Neoplasms , Ambulatory Care Facilities , Canada , Head and Neck Neoplasms/diagnosis , Head and Neck Neoplasms/epidemiology , Head and Neck Neoplasms/therapy , Health Personnel , Humans , Referral and Consultation
14.
Anaesthesia ; 75(8): 1022-1027, 2020 08.
Article in English | MEDLINE | ID: mdl-32348561

ABSTRACT

The COVID-19 pandemic has increased the demand for disposable N95 respirators. Re-usable elastomeric respirators may provide a suitable alternative. Proprietary elastomeric respirator filters may become depleted as demand increases. An alternative may be the virus/bacterial filters used in anaesthesia circuits, if they can be adequately fitted onto the elastomeric respirators. In addition, many re-usable elastomeric respirators do not filter exhaled breaths. If used for sterile procedures, this would also require modification. We designed a 3D-printed adaptor that permits elastomeric respirators to interface with anaesthesia circuit filters and created a simple modification to divert exhaled breaths through the filter. We conducted a feasibility study evaluating the performance of our modified elastomeric respirators. A convenience sample of eight volunteers was recruited. Quantitative fit testing, respiratory rate and end-tidal carbon dioxide were recorded during fit testing exercises and after 1 h of wear. All eight volunteers obtained excellent quantitative fit testing throughout the trial. The mean (SD) end-tidal carbon dioxide was 4.5 (0.5) kPa and 4.6 (0.4) kPa at baseline and after 1 h of wear (p = 0.148). The mean (SD) respiratory rate was 17 (4) breaths.min-1 and 17 (3) breaths.min-1 at baseline and after 1 h of wear (p = 0.435). Four out of eight subjects self-reported discomfort; two reported facial pressure, one reported exhalation resistance and one reported transient dizziness on exertion. Re-usable elastomeric respirators to utilise anaesthesia circuit filters through a 3D-printed adaptor may be a potential alternative to disposable N95 respirators during the COVID-19 pandemic.


Subject(s)
Betacoronavirus , Coronavirus Infections/therapy , Filtration/instrumentation , Pneumonia, Viral/therapy , Ventilators, Mechanical , Adult , COVID-19 , Carbon Dioxide/physiology , Coronavirus Infections/epidemiology , Elastomers , Equipment Design , Equipment Reuse , Feasibility Studies , Female , Humans , Male , Materials Testing/methods , Middle Aged , Pandemics , Pneumonia, Viral/epidemiology , Printing, Three-Dimensional , Respiratory Rate , SARS-CoV-2 , Ventilators, Mechanical/supply & distribution
15.
J Otolaryngol Head Neck Surg ; 49(1): 23, 2020 Apr 27.
Article in English | MEDLINE | ID: mdl-32340627

ABSTRACT

INTRODUCTION: The performance of tracheotomy is a common procedural request by critical care departments to the surgical services of general surgery, thoracic surgery and otolaryngology - head & neck surgery. A Canadian Society of Otolaryngology - Head & Neck Surgery (CSO-HNS) task force was convened with multi-specialty involvement from otolaryngology-head & neck surgery, general surgery, critical care and anesthesiology to develop a set of recommendations for the performance of tracheotomies during the COVID-19 pandemic. MAIN BODY: The tracheotomy procedure is highly aerosol generating and directly exposes the entire surgical team to the viral aerosol plume and secretions, thereby increasing the risk of transmission to healthcare providers. As such, we believe extended endotracheal intubation should be the standard of care for the entire duration of ventilation in the vast majority of patients. Pre-operative COVID-19 testing is highly recommended for any non-emergent procedure. CONCLUSION: The set of recommendations in this document highlight the importance of avoiding tracheotomy procedures in patients who are COVID-19 positive if at all possible. Recommendations for appropriate PPE and environment are made for COVID-19 positive, negative and unknown patients requiring consideration of tracheotomy. The safety of healthcare professionals who care for ill patients and who keep critical infrastructure operating is paramount.


Subject(s)
Coronavirus Infections/diagnosis , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Pandemics , Personal Protective Equipment/standards , Pneumonia, Viral/diagnosis , Respiratory Insufficiency/surgery , Tracheostomy/standards , COVID-19 , Canada , Coronavirus Infections/complications , Coronavirus Infections/epidemiology , Humans , Intubation, Intratracheal , Pneumonia, Viral/complications , Pneumonia, Viral/epidemiology , Respiration, Artificial , Respiratory Insufficiency/etiology , Time Factors , Tracheostomy/methods , Tracheotomy
17.
Int J Hyperthermia ; 37(3): 141-154, 2020 12.
Article in English | MEDLINE | ID: mdl-33426994

ABSTRACT

Magnetic fluid hyperthermia (MFH) has been widely investigated as a treatment tool for cancer and other diseases. However, focusing traditional MFH to a tumor deep in the body is not feasible because the in vivo wavelength of 300 kHz very low frequency (VLF) excitation fields is longer than 100 m. Recently we demonstrated that millimeter-precision localized heating can be achieved by combining magnetic particle imaging (MPI) with MFH. In principle, real-time MPI imaging can also guide the location and dosing of MFH treatments. Hence, the combination of MPI imaging plus real time localized MPI-MFH could soon permit closed-loop high-resolution hyperthermia treatment. In this review, we will discuss the fundamentals of localized MFH (e.g. physics and biosafety limitations), hardware implementation, MPI real-time guidance, and new research directions on MPI-MFH. We will also discuss how the scale up to human-sized MPI-MFH scanners could proceed.


Subject(s)
Hyperthermia, Induced , Magnetite Nanoparticles , Diagnostic Imaging , Humans , Hyperthermia , Magnetic Fields , Magnetics
18.
Ophthalmol Retina ; 3(10): 879-887, 2019 10.
Article in English | MEDLINE | ID: mdl-31229419

ABSTRACT

PURPOSE: To evaluate the vascular structure within combined hamartoma of retina and retinal pigment epithelium (CHRRPE) lesions using OCT angiography (OCTA). DESIGN: Multicenter, retrospective, observational analysis, PARTICIPANTS: Twenty eyes of patients diagnosed with CHRRPE. METHODS: Retrospective analysis of color fundus photographs, OCT, and OCTA of 20 eyes with CHRRPE. Morphologic characteristics of CHRRPE and the OCT features were correlated with the density of the filigree vascular pattern and with the published histopathologic findings of CHRRPE lesions. MAIN OUTCOME MEASURE: Density of flow signals, that is, the filigree vascular pattern seen on OCTA in the deep capillary plexus, graded as high (>20), intermediate (10-20), or low (<10). RESULTS: Of 20 lesions, 11 were peripapillary, 8 were macular, and 1 was equatorial in location. A high density of filigree vascular pattern was observed in most peripapillary CHRRPE lesions, which also showed full-thickness retinal involvement (8/10). A low density of filigree pattern was seen in macular lesions, which showed partial-thickness retinal involvement and preretinal fibrosis (5/6). CONCLUSIONS: A filigree vascular pattern on OCTA is seen in CHRRPE lesions. High density of this pattern is noted in CHRRPE lesions with a peripapillary location, full-thickness retinal disorganization, and minimal preretinal fibrosis. These findings correlate well with published histopathologic findings of CHRRPE lesions both in terms of topographic and morphologic features. OCT angiography provides a promising method for further study of these lesions.


Subject(s)
Fluorescein Angiography/methods , Hamartoma/diagnosis , Retinal Diseases/diagnosis , Retinal Pigment Epithelium/pathology , Tomography, Optical Coherence/methods , Visual Acuity , Adolescent , Adult , Aged , Child , Female , Fundus Oculi , Humans , Male , Middle Aged , Retrospective Studies , Young Adult
19.
J Laryngol Otol ; 133(4): 339-343, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30924439

ABSTRACT

OBJECTIVES: Little is known about what shapes the choice of employment location in a competitive surgical specialty like otolaryngology - head and neck surgery. This study aimed to identify factors important in determining practice location among Canadian otolaryngologists METHODS: An online survey was distributed nationally to active members of the Canadian Society of Otolaryngology - Head and Neck Surgery. The survey collected data on general demographics, current practice description, training location, factors deemed important in practice location decisions, and job satisfaction. RESULTS: A total of 122 survey responses were collected, with a similar proportion of participants in academic versus community practice. The majority of respondents (73 per cent) practised in the same province as their residency training. Participants identified job vacancy, colleague interaction, spouse opinion and hospital services as important in the decision of practice location. CONCLUSION: Key determinants of practice location among Canadian otolaryngologists include job vacancies, spouse opinion, and colleague interactions. Overall, Canadian otolaryngologists report high satisfaction with current employment.


Subject(s)
Job Satisfaction , Otolaryngologists/psychology , Otolaryngology/organization & administration , Adult , Aged , Canada , Choice Behavior , Cross-Sectional Studies , Demography , Employment , Female , Humans , Internet , Male , Middle Aged , Societies, Medical , Surveys and Questionnaires
20.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Non-conventional in English | MedCarib | ID: biblio-1023182

ABSTRACT

Objectives: To establish normative Hand Grip Strength (HGS) data for Trinidad and Tobago and to assess factors that may influence hand grip strength within this population. Design and Methodology: A cross sectional study of participants between the ages of 18-80 years was conducted at five distinct geographic regions in Trinidad and Tobago. Demographic data was collected including hand dominance. HGS was measured using a Jamar dynamometer. Descriptive statistics were performed for all direct measurements and Pearson's correlation coefficient used to analyze the relationship between variables. All statistical analysis was performed using the Statistical Package for Social Sciences (SPSS v20) p-value < 0.05 was considered significant. Results: A total of 1354 participants took part in the study, with 121 exclusions leaving 1233 for analysis. There were 561 males (45.5%) and 672 females (54.5%). The mean age of the participants was 42.5 years (SD +/-15.5) and mean body mass index (kg/m2) 27.3 (SD +/- 6.0). The overall mean HGS for our sample was 28.4 kgs. (SD +/- 2.9) with males having a higher overall HGS compared with females. Conclusions: This study presents previously unreported normative data on HGS in a Trinidad and Tobago population. This data will allow for a more objective evaluation of hand function in patients following injury and has implications for the assessment of disability in workmen's compensation.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Hand Strength , Trinidad and Tobago
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