Incidence of acute cerebrovascular events in patients with rheumatic or calcific mitral stenosis: a systematic review and meta-analysis

Background Patients with mitral stenosis (MS) may be predisposed to acute cerebrovascular events (ACE) and peripheral thromboembolic events (TEE). Concomitant atrial fibrillation (AF), mitral annular calcification (MAC) and rheumatic heart disease (RHD) are independent risk factors. Our aim was to evaluate the incidence of ACEs in MS patients and the implications of AF, MAC, and RHD on thromboembolic risks. Methods This systematic review was registered on PROSPERO (CRD42021291316). Six databases were searched from inception to 19th December 2021. The clinical outcomes were composite ACE, ischaemic stroke/transient ischaemic attack (TIA), and peripheral TEE. Results We included 16 and 9 papers, respectively, in our qualitative and quantitative analyses. The MS cohort with AF had the highest incidence of composite ACE (31.55%; 95%CI 3.60-85.03; I 2 =99%), followed by the MAC (14.85%; 95%CI 7.21-28.11; I 2 =98%), overall MS (8.30%; 95%CI 3.45-18.63; I 2 =96%) and rheumatic MS population (4.92%; 95%CI 3.53-6.83; I 2 =38%). Stroke/TIA were reported in 29.62% of the concomitant AF subgroup (95%CI 2.91-85.51; I 2 =99%) and in 7.11% of the overall MS patients (95%CI 1.91-23.16; I 2 =97%). However, the heterogeneity of the pooled incidence of clinical outcomes in all groups, except the rheumatic MS group, were substantial and significant. The logit-transformed proportion of composite ACE increased by 0.0141 (95% CI 0.0111-0.0171; p<0.01) per year of follow-up. Conclusion In the MS population, MAC and concomitant AF are risk factors for the development of ACE. The scarcity of data in our systematic review reflects the need for further studies to explore thromboembolic risks in all MS subtypes

Alignment of electrospun PCL scaffold

Electrospinning process, a simple and versatile set up for the fabrication of fibers textiles is capable of mimicking the native extracellular matrix structure. In tissue engineering, there is a need to fabricate electrospun scaffold with moderate mechanical strength which can sustain cyclic stretching to give appropriate mechanical stimulation to stem cell. Besides, the surface topology of the scaffold is also important in cell growth. Efficacy of aligned poly (ε-caprolactone) (PCL) nanofibrous scaffolds for tissue engineering is described. Uniaxially aligned PCL fibrous scaffolds of diameter 0.57±0.03μm were fabricated by an electrospinning technique under optimized condition (accelerating voltage: 25kV, rotating speed: 1500rpm, feed rate: 0.5ml/h) and the diameter of the electrospun fibers can easily be tailored by adjusting the feed rate and rotation speed of drum collector. In comparison, randomly oriented PCL scaffold were produced to study the fiber alignment influence in cell behavior. The optimal parameters to fabricate aligned and randomly oriented scaffold were discussed. The characterization of the scaffolds was carried out. Aligned electrospun scaffold has Young’s modulus of 12.75MPa. It was found that electrospun scaffold is more hydrophobic than casted scaffold. Besides, electrospun scaffold showed higher crystallinity than casted scaffold and aligned scaffold has slightly higher crystallinity than randomly oriented scaffold. Cell culture of human Mesenchymal Stem Cell (hMSCs) on electrospun scaffolds was carried out to study the cell attachment, proliferation and morphology. Cells attached and proliferated well on electrospun scaffolds compared to casted scaffold as the cell viability measured quantitatively by CCK-8 absorbance at 450nm is higher. The crystal violet staining micrographs showed that the cells grew along the direction of the fiber on aligned scaffold while distributed evenly on casted scaffold. In addition, the cell shape changed from circular shape to spindle-shaped on electrospun scaffold. These implied that the surface topology gives some signal to cell behavior and thus electrospun scaffold is a potential candidate as scaffold for hMSCs.Bachelor of Engineering (Materials Engineering

Lateral thyroid cartilage thyrotomy approach to an embedded paraglottic fishbone

Fishbones are of particular interest to otolaryngologists. Most fishbones can be removed transorally or via endoscopic guidance. Transcervical neck exploration is occasionally necessary, especially in cases of an embedded foreign body. Computed tomography is the most sensitive and specific imaging modality for identifying embedded fishbones. To our knowledge, this is the first reported case of a laryngeal foreign body embedded in the paraglottic space that was removed using an open approach via a lateral thyroid cartilage window

Advances in the diagnosis of foot-and-mouth disease

Foot-and-mouth disease (FMD) is a devastating livestock disease caused by foot-and-mouth disease virus (FMDV). Outbreaks of this disease in a country always result in conspicuous economic losses to livestock industry and subsequently lead to serious socioeconomic damages due to the immediate imposition of trade embargo. Rapid and accurate diagnoses are imperative to control this infectious virus. In the current review, enzyme-linked immunosorbent assay (ELISA)-based methods used in FMD diagnosis are extensively reviewed, particularly the sandwich, liquid-phase blocking, and solid-phase competition ELISA. The differentiation of infected animals from vaccinated animals using ELISA-based methods is also highlighted, in which the role of 3ABC polyprotein as a marker is reviewed intensively. Recently, more studies are focusing on the molecular diagnostic methods, which detect the viral nucleic acids based on reverse transcription-polymerase chain reaction (RT-PCR) and RT-loop-mediated isothermal amplification (RT-LAMP). These methods are generally more sensitive because of their ability to amplify a minute amount of the viral nucleic acids. In this digital era, the RT-PCR and RT-LAMP are progressing toward the mobile versions, aiming for on-site FMDV diagnosis. Apart from RT-PCR and RT-LAMP, another diagnostic assay specifically designed for on-site diagnosis is the lateral flow immunochromatographic test strips. These test strips have some distinct advantages over other diagnostic methods, whereby the assay often does not require the aid of an external device, which greatly lowers the cost per test. In addition, the on-site diagnostic test can be easily performed by untrained personnel including farmers, and the results can be obtained in a few minutes. Lastly, the use of FMDV diagnostic assays for progressive control of the disease is also discussed critically

Direct and indirect low skill fibre-optic intubation: A randomised crossover manikin study of six supraglottic airway devices

Background and Aims: Fibre-optic intubation (FOI) through supraglottic airway devices (SADs) is useful in the management of the difficult airway. We compared two methods of FOI through seven SADs in a randomised crossover manikin study to assess each device's performance and discuss implications on SAD selection. Methods: Thirty anaesthetsiologists, 15 seniors and 15 juniors, each performed low skill FOI (LSFOI) with seven SADs using both 'direct' and 'indirect' methods. The order of method and device used were randomised. The primary end point was success rate of intubation; secondary end points were time taken for intubation, incidence of difficulties with direct and indirect LSFOI and operator device preference. Statistical analysis was with univariable analysis and comparison of proportions. Results: Data from six devices were analysed due to a protocol breach with one SAD. There was no difference in intubation success rate across all SADs and intubation methods. Intubation time was significantly shorter in AmbuAuragain than other SADs and shorter with the direct method of LSFOI than the indirect method (mean difference of 6.9 s, P = 0.027). Ambu Auragain had the least SAD and bronchoscope-related difficulties. Seniors had significantly shorter mean intubation times than juniors by 11.6 s (P = 0.0392). The most preferred SAD for both methods was AmbuAuragain. Conclusion: Low skill FOI consistently achieves a high intubation success rate regardless of experience, choice of method, or SAD used. SAD design features may significantly affect the performance of low skill FOI

Antiviral activity of traditional Chinese medicinal plants Dryopteris crassirhizoma and Morus alba against dengue virus

Dengue virus (DENV) has emerged as a major virus that is spread by mosquitoes. Recently, it has spread to more than a hundred nations but continues to lack specific treatable medication. Many traditional Chinese medicinal (TCM) plants are in practice for dengue fever in dengue endemic regions. These traditional medicines persevere with treatments, which modern medicines lack. The study aims to substantiate the anti-dengue potential of some traditional herbs and make them available for further studies to facilitate TCM users. Twelve TCM plants aqueous extracts were evaluated, which are described as cool herbs used for the diseases with high fever. Lead plants were established through detailed in vitro foci forming unit reduction analysis (FFURA) against all four serotypes and validated through quantitative real-time RT-PCR (qRT-PCR). Four plants potentially inhibited the virus in primary phenotypic in vitro evaluation. Two lead plants Dryopteris crassirhizoma (DC) and Morus alba (MA) were identified with half minimal inhibitory concentration (IC50) 130 and 221 μg mL−1, respectively, while the selectivity indices (SI) were 4.21 and 4.62, respectively. Lead plants equally inhibited all four serotypes of DENV. Time-of-addition analysis suggested that, DC was active at later stages of viral replication, whereas MA was active during the early stages and even showed some prophylactic activity. Liquid chromatography-mass spectrometry (HPLC/MS) analysis revealed presence of flavonoids. DC and MA are identified as potential anti-dengue plants, active against varied stages of dengue virus replication cycle. These results may serve as the base knowledge for further investigation on their combined treatments or integrative treatment with western medicines, which may improve the overall anti-dengue activity in future

Sleep apnea and recurrent heart failure hospitalizations after coronary artery bypass grafting

10.5664/jcsm.9442JOURNAL OF CLINICAL SLEEP MEDICINE17122399-240

Electronically Transparent Graphene Barriers against Unwanted Doping of Silicon

Diffusion barriers prevent materials from intermixing (e.g., undesired doping) in electronic devices. Most diffusion barrier materials are often very specific for a certain combination of materials and/or change the energetics of the interface because they are insulating or add to the contact resistances. This paper presents graphene (Gr) as an electronically transparent, without adding significant resistance to the interface, diffusion barrier in metal/semiconductor devices, where Gr prevents Au and Cu from diffusion into the Si, and unintentionally dope the Si. We studied the electronic properties of the <i>n</i>-Si­(111)/Gr/M Schottky barriers (with and without Gr and M = Au or Cu) by <i>I</i>(<i>V</i>) measurements and at the nanoscale by ballistic electron emission spectroscopy (BEEM). The layer of Gr does not change the Schottky barrier of these junctions. The Gr barrier was stable at 300 °C for 1 h and prevented the diffusion of Cu into <i>n</i>-Si­(111) and the formation of Cu₃Si. Thus, we conclude that the Gr is mechanically and chemically stable enough to withstand the harsh fabrication methods typically encountered in clean room processes (e.g., deposition of metals in high vacuum conditions at high temperatures), it is electronically transparent (it does not change the energetics of the Si/Au or Si/Cu Schottky barriers), and effectively prevented diffusion of the Cu or Au into the Si at elevated temperatures and vice versa

Induction of Myogenic Differentiation of Human Mesenchymal Stem Cells Cultured on Notch Agonist (Jagged-1) Modified Biodegradable Scaffold Surface

Engineered scaffold surface provides stem cells with vital cues that could determine the eventual fate of stem cells. In this work, biodegradable poly­(l-lactide-<i>co</i>-ε-caprolactone) (PLCL) scaffold conjugated with Notch agonist-Jagged-1­(JAG) peptide (2.1 kDa) was prepared to initiate myogenic differentiation of human mesenchymal stem cells (hMSCs). The scaffold surface was activated with oxygen plasma and acrylic acid was engrafted via UV polymerization to form a surface bearing carboxylic groups. JAG peptide was subsequently immobilized onto the carboxylated scaffold surface. Surface chemistry and topography were examined using attenuated total reflection Fourier transform infrared, X-ray photoelectron spectroscopy, and atomic force microscopy. Quantitative real time polymerase chain reaction analysis revealed activation of the Notch pathway; furthermore, several specific markers associated with myogenic but not osteogenic differentiation were shown to be up-regulated in hMSCs cultured on the engineered surface. The pro-myocardial effect of surface bound JAG peptide was further affirmed via immunodetection of the distinct myocardial marker, cardiac troponin T. Collectively, our results suggest that PLCL conjugated JAG peptide is a viable strategy to enhance the functional potential of scaffolds to be used as a bioengineered cardiac patch in myocardial infarction repair

Incidence of acute cerebrovascular events in patients with rheumatic or calcific mitral stenosis: A systematic review and meta-analysis

Background: Patients with mitral stenosis (MS) may be predisposed to acute cerebrovascular events (ACE) and peripheral thromboembolic events (TEE). Concomitant atrial fibrillation (AF), mitral annular calcification (MAC) and rheumatic heart disease (RHD) are independent risk factors. Our aim was to evaluate the incidence of ACEs in MS patients and the implications of AF, MAC and RHD on thromboembolic risks. Methods: This systematic review was registered on PROSPERO (CRD42021291316). Six databases were searched from inception to 19th December 2021. The clinical outcomes were composite ACE, ischaemic stroke/transient ischaemic attack (TIA) and peripheral TEE. Results: We included 16 and 9 papers, respectively, in our qualitative and quantitative analyses. The MS cohort with AF had the highest incidence of composite ACE (31.55%; 95% CI 3.60–85.03; I2 = 99%), followed by the MAC (14.85%; 95% CI 7.21–28.11; I2 = 98%), overall MS (8.30%; 95% CI 3.45–18.63; I2 = 96%) and rheumatic MS population (4.92%; 95% CI 3.53–6.83; I2 = 38%). Stroke/TIA were reported in 29.62% of the concomitant AF subgroup (95% CI 2.91–85.51; I2 = 99%) and in 7.11% of the overall MS patients (95% CI 1.91–23.16; I2 = 97%). However, the heterogeneity of the pooled incidence of clinical outcomes in all groups, except the rheumatic MS group, was substantial and significant. The logit-transformed proportion of composite ACE increased by 0.0141 (95% CI 0.0111–0.0171; p < 0.01) per year of follow-up. Conclusion: In the MS population, MAC and concomitant AF are risk factors for the development of ACE. The scarcity of data in our systematic review reflects the need for further studies to explore thromboembolic risks in all MS subtypes