Telemedicine acceptance by older adults in Hong Kong during a hypothetical severe outbreak and after the COVID-19 pandemic: a cross-sectional cohort survey.

INTRODUCTION: Telemedicine services worldwide have experienced unprecedented growth since the early days of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have shown that telemedicine is an effective alternative to conventional in-person patient care. This study explored the public perception of telemedicine in Hong Kong, specifically among older adults who are most vulnerable to COVID-19. METHODS: Medical students from The Chinese University of Hong Kong conducted in-person surveys of older adults aged ≥60 years. Each survey collected socio-demographic information, medical history, and concerns regarding telemedicine use. Univariate and multivariate logistic regression analyses were conducted to identify statistically significant associations. The primary outcomes were acceptance of telemedicine use during a hypothetical severe outbreak and after the COVID-19 pandemic. RESULTS: There were 109 survey respondents. Multivariate logistic regression analyses revealed that the expectation of government subsidies for telemedicine services was the strongest common driver and the only positive independent predictor of telemedicine use during a hypothetical severe outbreak (P=0.016) and after the COVID-19 pandemic (P=0.003). No negative independent predictors of telemedicine use during a hypothetical severe outbreak were identified. Negative independent predictors of telemedicine use after the COVID-19 pandemic included older age and residence in the New Territories (both P=0.001). CONCLUSION: Government support, such as telemedicine-specific subsidies, will be important for efforts to promote telemedicine use in Hong Kong during future severe outbreaks and after the COVID-19 pandemic. Robust dissemination of information regarding the advantages and disadvantages of telemedicine for the public, especially older adults, is needed.

Measurement of diabetic wounds with optical coherence tomography-based air-jet indentation system and a material testing system.

OBJECTIVE: Material testing system is a conventional but destructive method for measuring the biomechanical properties of wound tissues in basic research. The recently developed optical coherence tomography-based air-jet indentation system is a non-destructive method for measuring these properties of soft tissues in a non-contact manner. The aim of the study was to examine the correlation between the biomechanical properties of wound tissues measured by the two systems. METHOD: Young male Sprague-Dawley rats with streptozotocin-induced diabetic were wounded by a 6 mm biopsy punch on their hind limbs. The biomechanical properties of wound tissues were assessed with the two systems on post-wounding days 3, 7, 10, 14, and 21. Wound sections were stained with picro-sirius red for analysis on the collagen fibres. Data obtained on the different days were charted to obtain the change in biomechanical properties across the time points, and then pooled to examine the correlation between measurements made by the two devices. Qualitative analysis to determine any correlation between indentation stiffness measured by the air-jet indentation system and the orientation of collagen fibres. RESULTS: The indentation stiffness is significantly negatively correlated to the maximum load, maximum tensile stress, and Young's modulus by the material testing system (all p<0.05). The orientation of collagen changes with the indentation stiffness over time. CONCLUSION: Our findings support the use of optical coherence tomography-based air-jet indentation system to evaluate the biomechanical properties of wounds in a non-contact manner. It is a potential clinical device to examine the biomechanical properties of chronic wounds in vivo in a repeatable manner.

Aspirin desensitisation for Chinese patients with coronary artery disease.

OBJECTIVE. To assess the efficacy and safety of aspirin desensitisation in Chinese patients with coronary artery disease. DESIGN. Case series. SETTING. A regional hospital in Hong Kong. PATIENTS. Chinese patients with coronary artery disease and a history of a hypersensitivity reaction to aspirin or non-steroidal anti-inflammatory drug, who underwent aspirin desensitisation between February 2008 and July 2012. RESULTS. There were 24 Chinese patients with coronary artery disease who were admitted to our unit for aspirin desensitisation during this period. The majority (79%) were clinical admissions for desensitisation; eight (33%) of them developed a hypersensitivity reaction during desensitisation. Half of the latter had only limited cutaneous reactions and were able to complete the desensitisation protocol and developed aspirin tolerance. Overall, 20 (83%) of the patients were successfully desensitised at the initial attempt. No serious adverse reactions occurred in the cohort. Twelve of the patients had significant coronary artery disease revealed by coronary angiography and received a percutaneous coronary intervention, nine of whom received drug-eluting stents while three received bare metal stents due to financial constraints. All 11 successfully desensitised patients received aspirin and clopidogrel as double antiplatelet therapy after percutaneous coronary intervention. The remaining patient had a bare metal stent implant due to failed aspirin desensitisation. CONCLUSION. Given the potentially different genetic basis of aspirin hypersensitivity in different ethnicities, recourse to desensitisation in the Chinese population has not previously been addressed. This study demonstrated that aspirin desensitisation using a rapid protocol can be performed effectively and safely in Chinese patients. Our results were comparable to those in other reported studies involving other ethnicities. Successful aspirin desensitisation permits patients to pursue long-term double antiplatelet therapy that includes aspirin after percutaneous coronary intervention, and thus allows the use of drug-eluting stents as a feasible option.

Reperfusion strategy for ST-segment elevation myocardial infarction: trend over a 10-year period.

OBJECTIVES. To review the 10-year trend of reperfusion strategies in patients with ST-segment elevation myocardial infarction, and the adoption rate of percutaneous coronary interventions as opposed to thrombolytic therapy. Also to explore why some patients did not receive reperfusion therapy, and document changes in reperfusion strategies after the introduction of primary percutaneous coronary intervention programmes. DESIGN. Case series. SETTING. A regional hospital, Hong Kong. PATIENTS. All patients with ST-segment elevation myocardial infarction from January 2000 to December 2009. RESULTS. There were 1835 patients with ST-segment elevation myocardial infarction in that period, of which 1179 (64.3%) received reperfusion therapy (thrombolytic therapy, 46.0%; primary percutaneous coronary intervention, 17.5%; emergency coronary artery bypass graft, 0.7%). After introduction of the primary percutaneous coronary intervention programme, significantly more ST-segment elevation myocardial infarction cases underwent that particular intervention (1.6% in 2000 increasing to 30.6% in 2009), while the proportion receiving thrombolytic therapy declined (57.4% in 2000 decreasing to 35.0% in 2009). Seven reasons for no reperfusion therapy were identified. The commonest ones were delayed presentation (45.1%), succumbed before reperfusion (16.0%), multiple medical co-morbidities (15.2%), and contra-indication to thrombolytic therapy (14.8%). The proportion without reperfusion therapy due to a contra-indication to thrombolytic therapy declined (22.7% in 2000 decreasing to 4.9% to 2009), whilst an increasing proportion received primary percutaneous coronary interventions. CONCLUSIONS. Primary percutaneous coronary intervention is increasingly used as the reperfusion therapy in ST-segment elevation myocardial infarction and is replacing thrombolytic therapy, though the latter still remains a mainstay of therapy. A significant proportion of ST-segment elevation myocardial infarction cases received no reperfusion due to various reasons.

Malignant peripheral nerve sheath tumour in the liver of a dog.

A 14-year-old male mixed breed dog was presented for abdominal distension and abdominal pain. Radiographical examination identified a large space-occupying mass in the abdomen. Necropsy examination revealed the presence of a 12cm hepatic mass that occupied almost half of the abdominal cavity. Microscopically, this mass consisted of spindle-shaped neoplastic cells that were arranged in short streams and interlacing bundles. Immunohistochemically, the neoplastic cells expressed vimentin, S-100, protein gene product 9.5 and neuron specific enolase, but were negative for cytokeratin, smooth muscle actin, melan A and von Willebrand Factor. These findings indicated that the hepatic mass was a primary hepatic peripheral nerve sheath tumour. To our knowledge, this is the first documentation of a primary hepatic malignant peripheral nerve sheath tumour in a dog.

Characterization of a linear device developed for research on advanced plasma imaging and dynamics.

Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10(-8) Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.

Primary percutaneous coronary intervention for ST elevation myocardial infarction: performance with focus on timeliness of treatment.

OBJECTIVE: To review primary percutaneous coronary interventions performed for patients with ST elevation myocardial infarction with a focus on door-to-treatment time, especially after introduction of a new management programme in November 2003. DESIGN: Retrospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: All patients with ST elevation myocardial infarction who underwent primary percutaneous coronary intervention in our hospital from January 2002 to December 2007. RESULTS: In all, 209 patients with ST elevation myocardial infarction had primary percutaneous coronary interventions between January 2002 and December 2007; 140 of them were admitted within office hours, 125 of whom came directly from Accident and Emergency Department. The mean door-to-balloon time of these patients was 115 minutes, and in 41% the time was less than 90 minutes (as recommended by the American College of Cardiology/American Heart Association guidelines). Since introduction of the new programme, the mean door-to-balloon time has diminished significantly, from 146 to 116 minutes (P=0.047). Delay in diagnosis (28%) and Cardiac Catheterization Laboratory being occupied (20%) were the two most common reasons for prolonged door-to-balloon times. CONCLUSION: We achieved satisfactory performance in our primary percutaneous coronary intervention programme, providing timely reperfusion therapy for patients with ST elevation myocardial infarction. A well-organised and systematic clinical pathway is a prerequisite for a centre that provides a timely and effective primary percutaneous coronary intervention service for patients with ST elevation myocardial infarction. Better public education and greater awareness on the part of medical service providers are needed, so as to facilitate urgent revascularisation and improve outcomes in patients with ST elevation myocardial infarction.

Liquid-crystal periodic zigzags from geometrical and surface-anchoring-induced confinement: origin and internal structure from mesoscopic scale to molecular level.

We figured out periodic undulations of lamellae "zigzags" in liquid crystals under confinement by glass and patterned silicon hybrid cell, but in the absence of applied fields. The optical and internal structures of zigzags have been investigated from mesoscopic scale to molecular level by convoluting real and reciprocal space probes, such as polarized light microscopy, scanning electron microscopy, and microbeam x-ray diffraction. The homeotropic anchoring happens at air/liquid crystal, while planar one appears at glass or patterned silicon surfaces. The wetting and displacement of lamellae near the glass surface give rise to tilting and bending in the stacking of lamellae. This can provide a solution for the origin of periodic zigzags: asymmetric strain exerted to lamellae at two-dimensional glass surface and one-dimensional-like pattern. This can give a hint for potential photonic applications such as optical gratings and modulators due to its high periodicity.

Descriptions of a linear device developed for research on advanced plasma imaging and dynamics.

The research on advanced plasma imaging and dynamics (RAPID) device is a newly developed linear electron cyclotron resonance (ECR) plasma device. It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. A 6 kW 2.45 GHz magnetron is used to produce steady-state ECR plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). The cylindrical stainless steel vacuum chamber is 300 mm in diameter and 750 mm in length and has eight radial and ten axial ports including 6-in. and 8-in. viewing windows for heating and diagnostics. Experimental observation of ECR plasma heating has been recently carried out during the initial plasma operation. The main diagnostic systems including a 94 GHz heterodyne interferometer, a high-resolution 25 channel one-dimensional array spectrometer, a single channel survey spectrometer, and an electric probe have been also prepared. The RAPID device is a flexible simulator for the understanding of tokamak edge plasma physics and new diagnostic system development. In this work, we describe the RAPID device and initial operation results.

Human microtubule-associated-protein tau regulates the number of protofilaments in microtubules: a synchrotron x-ray scattering study.

Microtubules (MTs), a major component of the eukaryotic cytoskeleton, are 25 nm protein nanotubes with walls comprised of assembled protofilaments built from alphabeta heterodimeric tubulin. In neural cells, different isoforms of the microtubule-associated-protein (MAP) tau regulate tubulin assembly and MT stability. Using synchrotron small angle x-ray scattering (SAXS), we have examined the effects of all six naturally occurring central nervous system tau isoforms on the assembly structure of taxol-stabilized MTs. Most notably, we found that tau regulates the distribution of protofilament numbers in MTs as reflected in the observed increase in the average radius R(MT) of MTs with increasing Phi, the tau/tubulin-dimer molar ratio. Within experimental scatter, the change in R(MT) seems to be isoform independent. Significantly, R(MT) was observed to rapidly increase for 0 < Phi < 0.2 and saturate for Phi between 0.2-0.5. Thus, a local shape distortion of the tubulin dimer on tau binding, at coverages much less than a monolayer, is spread collectively over many dimers on the scale of protofilaments. This implies that tau regulates the shape of protofilaments and thus the spontaneous curvature C(o)(MT) of MTs leading to changes in the curvature C(MT) (=1/R(MT)). An important biological implication of these findings is a possible allosteric role for tau where the tau-induced shape changes of the MT surface may effect the MT binding activity of other MAPs present in neurons. Furthermore, the results, which provide insight into the regulation of the elastic properties of MTs by tau, may also impact biomaterials applications requiring radial size-controlled nanotubes.

Confined self-assembly of toric focal conic domains (the effects of confined geometry on the feature size of toric focal conic domains).

A smectic liquid crystal (LC) containing a rigid biphenyl group and semifluorinated chains exhibits a high density of toric focal conic domains (TFCDs) arranged in an ordered array when confined within a microchannel. The formation of the TFCDs is strongly influenced by the width (W) and depth (h) of the confined microchannels, most importantly, by the channel depth. We studied a broad variety of microchannels, with varying width in the range of 3-200 mum and depth in the range of 2-10 mum. The radius of the TFCDs increases with increases in the width until the saturated radius is achieved, which is determined by the depth of the channel. We used the elastic-anchoring model of TFCD formation to explain the experimental observations. The model allows one to trace the dependence of the TFCD radius on the channel depth h, to explain why the TFCDs do not form in channels that are too shallow or too narrow.

Internal structure visualization and lithographic use of periodic toroidal holes in liquid crystals.

The formation of a large-area ordered structure by organic molecular soft building blocks is one of the most exciting interdisciplinary research areas in current materials science and nanotechnology. So far, several distinct organic building blocks--including colloids, block copolymers and surfactants--have been examined as potential materials for the creation of lithographic templates. Here, we report that perfect ordered arrays of toric focal conic domains (TFCDs) covering large areas can be formed by semi-fluorinated smectic liquid crystals. Combined with controlled geometry, that is, a microchannel, our smectic liquid-crystal system exhibits a high density of TFCDs that are arranged with remarkably high regularity. Direct visualization of the internal structure of the TFCDs clearly verified that the smectic layers were aligned normal to the side walls and parallel to the top surface, and merge with the circular profile on the bottom wall surface. Moreover, we demonstrate a new concept: smectic liquid-crystal lithography. Grown in microchannels from a mixture of liquid-crystal molecules and fluorescent particles, TFCDs of the smectic liquid crystals acted as a template, trapping particles in an ordered array. Our findings pose new theoretical challenges and potentially enable lithographic applications based on smectic liquid-crystalline materials.

Feasibility of transradial coronary angiography and angioplasty in Chinese patients.

OBJECTIVE: To assess the clinical applicability, efficacy, and safety of coronary angiography and angioplasty via a transradial approach in local Chinese patients. DESIGN: Prospective case series. SETTING: Regional hospital, Hong Kong. PATIENTS: All patients undergoing coronary angiography and coronary angioplasty between 1 January and 30 June 2004. INTERVENTIONS: Transradial coronary angiography and coronary angioplasty. MAIN OUTCOME MEASURES: Feasibility, success rate, and complications. RESULTS: A total of 268 coronary angiographies (62% of all coronary angiographies) and 118 coronary angioplasties (48% of all coronary angioplasties) were performed via a transradial approach. The procedural success rate for coronary angiography was 93.7% with a mean duration of 21.8 (standard deviation, 13.5) minutes compared with 17.9 (10.0) minutes for angiography via a femoral approach. Most (99%) patients were free from any complications. Of those patients who underwent elective transradial coronary angiography in the morning, 64% were discharged on the same day. Comparison of data in the first half of the study period with those in the second half revealed a significant increase in the percentage of coronary angiographies performed via a transradial approach (from 52% to 73%, P<0.0001), and an improved procedural success rate (from 91.5% to 95.3%, P=0.1). For transradial coronary angioplasty, the procedural success rate was 98%. A total of 246 lesions (2.08 lesions per patient) were treated with no procedure-related complications. CONCLUSIONS: Transradial coronary angiography and angioplasty are feasible in a significant proportion of local Chinese patients and achieve a high success rate and low complication rate. It tends to prolong procedural duration, but improves patients' comfort and permits earlier ambulation and discharge. The procedural success rate improves with accumulating experience.

Necrotic cardiac haemangioma masquerading as sepsis with disseminated intravascular coagulation.

Cardiac haemangiomas are exceptionally rare benign vascular tumours. We report a case of cardiac haemangioma presenting with pyrexia of unknown origin and clinical features simulating sepsis with disseminated intravascular coagulation. The clinical course was complicated by systemic embolism.

Okadaic acid, a causative toxin of diarrhetic shellfish poisoning, in green-lipped mussels Perna viridis from Hong Kong fish culture zones: method development and monitoring.

Green-lipped mussels (Perna viridis) were collected from seven fish culture zones (FCZs) in Hong Kong and analyzed for okadaic acid (OA). A conventional HPLC method was modified by incorporating a proteinase K digestion step. Results suggest that a higher recovery (2.5 times higher) of OA was obtained from spiked samples after the addition of 1.08 mg proteinase K in comparison with samples incubated without the proteolytic enzyme. For the hepatopancreas (HP) of individual field-collected mussels, the additional digestion step can enhance OA extraction by 3.1 times. Spatial and temporal variations in OA concentrations in the mussels from various FCZs were investigated. The highest concentration of OA in mussel HP samples was 1164.9 ng/g HP wet wt. With respect to OA concentrations in whole mussel tissues from seven sites and four seasonal samplings, the concentrations were between 70.0 and 131.0 ng/g wet wt., which did not exceed the generally recognized international regulatory criteria (>200 ng/g) for OA.

Radiographic contrast study of the upper gastrointestinal tract of eight dogs using carboxymethylcellulose mixed with a low concentration of barium sulphate.

To evaluate the efficacy of a mixture of barium and carboxymethylcellulose (CMC) suspension in upper gastrointestinal contrast studies, and to determine its optimal concentration and method for use, eight healthy beagle dogs underwent conventional upper gastrointestinal contrast imaging and a modified procedure using a mixture of barium sulphate and CMC. Four different procedures were carried out on the dogs at weekly intervals. In the first, the dogs were administered 10 ml/kg of 60 per cent barium suspension for conventional study of the upper gastrointestinal tract. The second, third and fourth procedures involved modified methods in which the dogs were given 10 ml/kg of a mixture of 25 per cent barium and 0.5 per cent CMC prepared to a low, moderate or high viscosity, respectively. All four procedures were evaluated by four criteria: the quality of the images obtained, the translucency and distensibility of the bowel, and the transit time. The method of imaging which used a moderately viscious CMC formulation provided excellent image quality, high translucency, a rapid transit time and suitable bowel distension to enable more precise diagnosis of disorders of the gastrointestinal tract.

The application of chiral aminonaphthols in the enantioselective addition of diethylzinc to aryl aldehydes.

[reaction: see text]. Optically active aminonaphthol 3 obtained by condensation of 2-naphthol, benzaldehyde, and (S)-methylbenzylamine followed by N-methylation was found to catalyze the enantioselective ethylation of aryl aldehydes to secondary alcohols with high enantioselectivities (up to 99.8%) at room temperature.

Scleral melanocytosis and oculodermal melanocytosis (nevus of Ota) in Chinese children.

Two thousand nine hundred fourteen Chinese children (1510 males and 1404 females) were examined for the presence of scleral melanocytosis (SM) and oculodermal melanocytosis in a cross-sectional prevalence survey. SM was found in 4.9% of boys and 4.1% of girls under the age of 1 year. The peak prevalence was at 6 years of age, when 44.6% of boys and 46.6% of girls were affected. At 18 years of age, only 11.1% of boys and 13.2% of girls had SM. The overall prevalence, regardless of age, was 27.6% in boys and 27. 1% in girls. The condition was bilateral in 78% of cases. The medial superior quadrant was the most frequently affected site, and the lateral inferior quadrant was the least frequently affected site. Oculodermal melanocytosis occurred only in one patient; the pigmentation affected the left side of the face and the ipsilateral sclera.