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A plethora of human pluripotent stem cells

Gao L, Thilakavathy K, Nordin N

Cell Biol Int, 2013 Sep;37(9):875-87.
PMID: 23619972 DOI: 10.1002/cbin.10120

At the early stages of mammalian development, a number of developmentally plastic cells appear that possess the ability to give rise to all of the differentiated cell types normally derived from the three primary germ layers - unique character known as pluripotency. To date, embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have been shown to be truly pluripotent. However, recent studies have revealed a variety of other cells that demonstrate pluripotentiality, including very small embryonic-like stem cells (VSELs), amniotic fluid stem cells (AFSCs), marrow-isolated adult multilineage inducible cells (MIAMI) and multipotent adult precursor cells (MAPCs). This review summarises key features of these six kinds of pluripotent and potentially pluripotent stem cells (ESCs, iPSCs, VSELs, AFSCs, MIAMI and MAPCs) and the evidence for their pluripotency properties.
Stink bean (Parkia speciosa) empty pod: a potent natural antidiabetic agent for the prevention of pancreatic and hepatorenal dysfunction in high fat diet/streptozotocin-induced type 2 diabetes in rats

Gao L, Zhang W, Yang L, Fan H, Olatunji OJ

Arch Physiol Biochem, 2023 Feb;129(1):261-267.
PMID: 33522287 DOI: 10.1080/13813455.2021.1876733

The present study investigated the effect of polyphenol-rich extract of Parkia speciosa (PPS) against pancreatic and hepatorenal dysfunction in high-fat diet (HFD)/streptozotocin (STZ)-induced diabetes. Diabetic rats were treated with PPS (100 and 400 mg/kg) and glibenclamide. The results revealed that diabetic rats displayed marked hyperglycaemia, hyperlipidaemia, hypoinsulinemia as well as alterations in serum renal and kidney function markers. Furthermore, diabetic rats showed significant increase in hepatorenal level of malonaldehyde as well as suppression of antioxidant enzyme activities. Whereas, diabetic rats that received PPS displayed marked attenuation in most of the aforementioned parameters compared to the untreated diabetic rats. Additionally, histological examination revealed restoration of histopathological alterations of the pancreas, liver, and kidney of PPS treated diabetic rats. In conclusion, the results demonstrated that PPS could decrease serum lipids and blood glucose level, enhance insulin level and hepatorenal antioxidant capacity, as well as ameliorate hepatorenal dysfunction in rats.
Fulltext Blockchain for Vehicular Internet of Things: Recent Advances and Open Issues

Peng C, Wu C, Gao L, Zhang J, Alvin Yau KL, Ji Y

Sensors (Basel), 2020 Sep 07;20(18).
PMID: 32906707 DOI: 10.3390/s20185079

The vehicular Internet of Things (IoT) comprises enabling technologies for a large number of important applications including collaborative autonomous driving and advanced transportation systems. Due to the mobility of vehicles, strict application requirements, and limited communication resources, the conventional centralized control fails to provide sufficient quality of service for connected vehicles, so a decentralized approach is required in the vicinity to satisfy the requirements of delay-sensitive and mission-critical applications. A decentralized system is also more resistant to the single point of failure problem and malicious attacks. Blockchain technology has been attracting great interest due to its capability of achieving a decentralized, transparent, and tamper-resistant system. There are many studies focusing on the use of blockchain in managing data and transactions in vehicular environments. However, the application of blockchain in vehicular environments also faces some technical challenges. In this paper, we first explain the fundamentals of blockchain and vehicular IoT. Then, we conduct a literature review on the existing research efforts of the blockchain for vehicular IoT by discussing the research problems and technical issues. After that, we point out some future research issues considering the characteristics of both blockchain and vehicular IoT.
Glycaemic responses in Asian and non-Asian people with type 2 diabetes initiating insulin glargine 100 units/mL: A patient-level pooled analysis of 16 randomised controlled trials

Chan JCN, Bunnag P, Chan SP, Tan ITI, Tsai ST, Gao L, et al.

Diabetes Res Clin Pract, 2018 Jan;135:199-205.
PMID: 29179974 DOI: 10.1016/j.diabres.2017.11.025

AIMS: To compare outcomes between Asian and non-Asian patients with type 2 diabetes (T2D) inadequately controlled on oral antidiabetic drugs (OADs) initiating insulin glargine 100 units (U)/mL (Gla-100) in randomised controlled clinical trials.
METHODS: Post hoc analysis of patient-level data (Asian n = 235; non-Asian n = 3351) from 16 trials.
RESULTS: At baseline, Asian patients were younger with lower body mass index (BMI), fasting C-peptide, and fasting plasma glucose (FPG) than non-Asian patients (all P 
First Report of Angiopsora paspalicola Causing Leaf Rust on Paspalum conjugatum in Malaysia

Khoo YW, Gao L, Khaw YS, Tan HT, Li S, Chong KP

Plant Dis, 2023 May 25.
PMID: 37227434 DOI: 10.1094/PDIS-01-23-0109-PDN

Paspalum conjugatum (family Poaceae), locally known as Buffalo grass, is a perennial weed that can be found in rice field, residential lawn, and sod farm in Malaysia (Uddin et al. 2010; Hakim et al. 2013). In September 2022, Buffalo grass with rust symptoms and signs were collected from the lawn located in Universiti Malaysia Sabah in the province of Sabah (6°01'55.6"N, 116°07'15.7"E). The incidence was 90%. Yellow uredinia were observed primarily on the abaxial surface of the leaves. As the disease progressed, leaves were covered with coalescing pustules. Microscopic examination of pustules revealed the presence of urediniospores. Urediniospores were ellipsoid to obovoid in shape, contents in yellow, 16.4-28.8 x 14.0-22.4 μm and echinulate, with a prominent tonsure on most of the spores. A fine brush was used to collect yellow urediniospores, and genomic DNA was extracted based on Khoo et al. (2022a). The primers Rust28SF/LR5 (Vilgalys and Hester 1990; Aime et al. 2018) and CO3_F1/CO3_R1 (Vialle et al. 2009) were used to amplify partial 28S ribosomal RNA (28S) and cytochrome c oxidase III (COX3) gene fragments following the protocols of Khoo et al. (2022b). The sequences were deposited in GenBank under accession numbers OQ186624- OQ186626 (985/985 bp) (28S) and OQ200381-OQ200383 (556/556 bp) (COX3). They were 100% similar to Angiopsora paspalicola 28S (MW049243) and COX3 (MW036496) sequences. Phylogenetic analysis using maximum likelihood based on the combined 28S and COX3 sequences indicated that the isolate formed a supported clade to A. paspalicola. Koch's postulates were performed with spray inoculations of urediniospores suspended in water (106 spores/ml) on leaves of three healthy Buffalo grass leaves, while water was sprayed on three additional Buffalo grass leaves which served as control. The inoculated Buffalo grass were placed in the greenhouse. Symptoms and signs similar to those of the field collection occurred after 12 days post inoculation. No symptoms occurred on controls. To our knowledge, this is the first report of A. paspalicola causing leaf rust on P. conjugatum in Malaysia. Our findings expand the geographic range of A. paspalicola in Malaysia. Albeit P. conjugatum is a host of the pathogen, but the host range of the pathogen especially in Poaceae economic crops need to be studied. Weed management could be an effective way to eliminate inoculum sources of A. paspalicola.
Fulltext Generation and consequence of nano/microplastics from medical waste and household plastic during the COVID-19 pandemic

Mohana AA, Islam MM, Rahman M, Pramanik SK, Haque N, Gao L, et al.

Chemosphere, 2023 Jan;311(Pt 2):137014.
PMID: 36328315 DOI: 10.1016/j.chemosphere.2022.137014

Since the end of 2019, the world has faced a major crisis because of the outbreak of COVID-19 disease which has created a severe threat to humanity. To control this pandemic, the World Health Organization gave some guidelines like wearing PPE (personal protective equipment) (e.g., face masks, overshoes, gloves), social distancing, hand hygiene and shutting down all modes of public transport services. During this pandemic, plastic products (e.g., household plastics, PPE and sanitizer bottles) have substantially prevented the spread of this virus. Since the outbreak, approximately 1.6 million tons of plastic waste have been generated daily. However, single-use PPE like face masks (N95), surgical masks and hand gloves contain many non-biodegradable plastics materials. These abandoned products have created a huge number of plastic debris which ended up as microplastics (MPs) followed by nanoplastics (NPs) in nature that are hazardous to the eco-system. These MPs and NPs also act as vectors for the various pathogenic contaminants. The goal of this review is to offer an extensive discussion on the formation of NPs and MPs from all of these abandoned plastics and their long-term impact on the environment as well as human health. This review paper also attempts to assess the present global scenario and the main challenge of waste management to reduce the potential NP/MPs pollution to improve the eco-systems.
Deciphering Adverse Detrapped Hole Transfer in Hot-Electron Photoelectric Conversion at Infrared Wavelengths

Yu Y, Gao L, Niu X, Liu K, Li R, Yang D, et al.

Adv Mater, 2023 Mar;35(12):e2210157.
PMID: 36732915 DOI: 10.1002/adma.202210157

Hot-carrier devices are promising alternatives for enabling path breaking photoelectric conversion. However, existing hot-carrier devices suffer from low efficiencies, particularly in the infrared region, and ambiguous physical mechanisms. In this work, the competitive interfacial transfer mechanisms of detrapped holes and hot electrons in hot-carrier devices are discovered. Through photocurrent polarity research and optical-pump-THz-probe (OPTP) spectroscopy, it is verified that detrapped hole transfer (DHT) and hot-electron transfer (HET) dominate the low- and high-density excitation responses, respectively. The photocurrent ratio assigned to DHT and HET increases from 6.6% to over 1133.3% as the illumination intensity decreases. DHT induces severe degeneration of the external quantum efficiency (EQE), especially at low illumination intensities. The EQE of a hot-electron device can theoretically increase by over two orders of magnitude at 10 mW cm-2 through DHT elimination. The OPTP results show that competitive transfer arises from the carrier oscillation type and carrier-density-related Coulomb screening. The screening intensity determines the excitation weight and hot-electron cooling scenes and thereby the transfer dynamics.
Telluride-Based Materials: A Promising Route for High Performance Supercapacitors

Khan AJ, Sajjad M, Khan S, Khan M, Mateen A, Shah SS, et al.

Chem Rec, 2024 Jan;24(1):e202300302.
PMID: 38010947 DOI: 10.1002/tcr.202300302

As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.
Broadband Nonlinear Photonics in Few-Layer Borophene

Ma C, Yin P, Khan K, Tareen AK, Huang R, Du J, et al.

Small, 2021 Jan 27.
PMID: 33502109 DOI: 10.1002/smll.202006891

In this paper, 2D borophene is synthesized through a liquid-phase exfoliation. The morphology and structure of as-prepared borophene are systemically analyzed, and the Z-scan is used to measure the nonlinear optical properties. It is found that the saturable absorber (SA) properties of borophene make it serve as an excellent broadband optical switch, which is strongly used for mode-locking in near- and mid-infrared laser systems. Ultrastable pulses with durations as short as 792 and 693 fs are successfully delivered at the central wavelengths of 1063 and 1560 nm, respectively. Furthermore, stable pulses at a wavelength of 1878 nm are demonstrated from a thulium mode-locked fiber laser based on the same borophene SA. This research reveals a significant potential for borophene used in lasers helping extending the frontiers of photonic technologies.
A phase III, multi-arm multi-stage covariate-adjusted response-adaptive randomized trial to determine optimal early mobility training after stroke (AVERT DOSE)

Bernhardt J, Churilov L, Dewey H, Donnan G, Ellery F, English C, et al.

Int J Stroke, 2023 Jul;18(6):745-750.
PMID: 36398582 DOI: 10.1177/17474930221142207

RATIONALE: The evidence base for acute post-stroke rehabilitation is inadequate and global guideline recommendations vary.
AIM: To define optimal early mobility intervention regimens for ischemic stroke patients of mild and moderate severity.
HYPOTHESES: Compared with a prespecified reference arm, the optimal dose regimen(s) will result in more participants experiencing little or no disability (mRS 0-2) at 3 months post-stroke (primary), fewer deaths at 3 months, fewer and less severe complications during the intervention period, faster recovery of unassisted walking, and better quality of life at 3 months (secondary). We also hypothesize that these regimens will be more cost-effective.
SAMPLE SIZE ESTIMATES: For the primary outcome, recruitment of 1300 mild and 1400 moderate participants will yield 80% power to detect a 10% risk difference.
METHODS AND DESIGN: Multi-arm multi-stage covariate-adjusted response-adaptive randomized trial of mobility training commenced within 48 h of stroke in mild (NIHSS 2) and hemorrhagic stroke. With four arms per stratum (reference arm retained throughout), only the single treatment arm demonstrating the highest proportion of favorable outcomes at the first stage will proceed to the second stage in each stratum, resulting in a final comparison with the reference arm. Three prognostic covariates of age, geographic region and reperfusion interventions, as well as previously observed mRS 0-2 responses inform the adaptive randomization procedure. Participants randomized receive prespecified mobility training regimens (functional task-specific), provided by physiotherapists/nurses until discharge or 14 days. Interventions replace usual mobility training. Fifty hospitals in seven countries (Australia, Malaysia, United Kingdom, Ireland, India, Brazil, Singapore) are expected to participate.
SUMMARY: Our novel adaptive trial design will evaluate a wider variety of mobility regimes than a traditional two-arm design. The data-driven adaptions during the trial will enable a more efficient evaluation to determine the optimal early mobility intervention for patients with mild and moderate ischemic stroke.
Fulltext Loss-free tensile ductility of dual-structure titanium composites via an interdiffusion and self-organization strategy

Liu L, Li S, Pan D, Hui D, Zhang X, Li B, et al.

Proc Natl Acad Sci U S A, 2023 Jul 11;120(28):e2302234120.
PMID: 37399391 DOI: 10.1073/pnas.2302234120

The deformation-coordination ability between ductile metal and brittle dispersive ceramic particles is poor, which means that an improvement in strength will inevitably sacrifice ductility in dispersion-strengthened metallic materials. Here, we present an inspired strategy for developing dual-structure-based titanium matrix composites (TMCs) that achieve 12.0% elongation comparable to the matrix Ti6Al4V alloys and enhanced strength compared to homostructure composites. The proposed dual-structure comprises a primary structure, namely, a TiB whisker-rich region engendered fine grain Ti6Al4V matrix with a three-dimensional micropellet architecture (3D-MPA), and an overall structure consisting of evenly distributed 3D-MPA "reinforcements" and a TiBw-lean titanium matrix. The dual structure presents a spatially heterogeneous grain distribution with 5.8 μm fine grains and 42.3 μm coarse grains, which exhibits excellent hetero-deformation-induced (HDI) hardening and achieves a 5.8% ductility. Interestingly, the 3D-MPA "reinforcements" show 11.1% isotropic deformability and 66% dislocation storage, which endows the TMCs with good strength and loss-free ductility. Our enlightening method uses an interdiffusion and self-organization strategy based on powder metallurgy to enable metal matrix composites with the heterostructure of the matrix and the configuration of reinforcement to address the strength-ductility trade-off dilemma.
IDRiD: Diabetic Retinopathy - Segmentation and Grading Challenge

Porwal P, Pachade S, Kokare M, Deshmukh G, Son J, Bae W, et al.

Med Image Anal, 2020 01;59:101561.
PMID: 31671320 DOI: 10.1016/j.media.2019.101561

Diabetic Retinopathy (DR) is the most common cause of avoidable vision loss, predominantly affecting the working-age population across the globe. Screening for DR, coupled with timely consultation and treatment, is a globally trusted policy to avoid vision loss. However, implementation of DR screening programs is challenging due to the scarcity of medical professionals able to screen a growing global diabetic population at risk for DR. Computer-aided disease diagnosis in retinal image analysis could provide a sustainable approach for such large-scale screening effort. The recent scientific advances in computing capacity and machine learning approaches provide an avenue for biomedical scientists to reach this goal. Aiming to advance the state-of-the-art in automatic DR diagnosis, a grand challenge on "Diabetic Retinopathy - Segmentation and Grading" was organized in conjunction with the IEEE International Symposium on Biomedical Imaging (ISBI - 2018). In this paper, we report the set-up and results of this challenge that is primarily based on Indian Diabetic Retinopathy Image Dataset (IDRiD). There were three principal sub-challenges: lesion segmentation, disease severity grading, and localization of retinal landmarks and segmentation. These multiple tasks in this challenge allow to test the generalizability of algorithms, and this is what makes it different from existing ones. It received a positive response from the scientific community with 148 submissions from 495 registrations effectively entered in this challenge. This paper outlines the challenge, its organization, the dataset used, evaluation methods and results of top-performing participating solutions. The top-performing approaches utilized a blend of clinical information, data augmentation, and an ensemble of models. These findings have the potential to enable new developments in retinal image analysis and image-based DR screening in particular.
Fulltext Epidemiology of anal human papillomavirus infection and high-grade squamous intraepithelial lesions in 29 900 men according to HIV status, sexuality, and age: a collaborative pooled analysis of 64 studies

Wei F, Gaisa MM, D'Souza G, Xia N, Giuliano AR, Hawes SE, et al.

Lancet HIV, 2021 Sep;8(9):e531-e543.
PMID: 34339628 DOI: 10.1016/S2352-3018(21)00108-9

BACKGROUND: Robust age-specific estimates of anal human papillomavirus (HPV) and high-grade squamous intraepithelial lesions (HSIL) in men can inform anal cancer prevention efforts. We aimed to evaluate the age-specific prevalence of anal HPV, HSIL, and their combination, in men, stratified by HIV status and sexuality.
METHODS: We did a systematic review for studies on anal HPV infection in men and a pooled analysis of individual-level data from eligible studies across four groups: HIV-positive men who have sex with men (MSM), HIV-negative MSM, HIV-positive men who have sex with women (MSW), and HIV-negative MSW. Studies were required to inform on type-specific HPV infection (at least HPV16), detected by use of a PCR-based test from anal swabs, HIV status, sexuality (MSM, including those who have sex with men only or also with women, or MSW), and age. Authors of eligible studies with a sample size of 200 participants or more were invited to share deidentified individual-level data on the above four variables. Authors of studies including 40 or more HIV-positive MSW or 40 or more men from Africa (irrespective of HIV status and sexuality) were also invited to share these data. Pooled estimates of anal high-risk HPV (HR-HPV, including HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68), and HSIL or worse (HSIL+), were compared by use of adjusted prevalence ratios (aPRs) from generalised linear models.
FINDINGS: The systematic review identified 93 eligible studies, of which 64 contributed data on 29 900 men to the pooled analysis. Among HIV-negative MSW anal HPV16 prevalence was 1·8% (91 of 5190) and HR-HPV prevalence was 6·9% (345 of 5003); among HIV-positive MSW the prevalences were 8·7% (59 of 682) and 26·9% (179 of 666); among HIV-negative MSM they were 13·7% (1455 of 10 617) and 41·2% (3798 of 9215), and among HIV-positive MSM 28·5% (3819 of 13 411) and 74·3% (8765 of 11 803). In HIV-positive MSM, HPV16 prevalence was 5·6% (two of 36) among those age 15-18 years and 28·8% (141 of 490) among those age 23-24 years (ptrend=0·0091); prevalence was 31·7% (1057 of 3337) among those age 25-34 years and 22·8% (451 of 1979) among those age 55 and older (ptrend<0·0001). HPV16 prevalence in HIV-negative MSM was 6·7% (15 of 223) among those age 15-18 and 13·9% (166 of 1192) among those age 23-24 years (ptrend=0·0076); the prevalence plateaued thereafter (ptrend=0·72). Similar age-specific patterns were observed for HR-HPV. No significant differences for HPV16 or HR-HPV were found by age for either HIV-positive or HIV-negative MSW. HSIL+ detection ranged from 7·5% (12 of 160) to 54·5% (61 of 112) in HIV-positive MSM; after adjustment for heterogeneity, HIV was a significant predictor of HSIL+ (aPR 1·54, 95% CI 1·36-1·73), HPV16-positive HSIL+ (1·66, 1·36-2·03), and HSIL+ in HPV16-positive MSM (1·19, 1·04-1·37). Among HPV16-positive MSM, HSIL+ prevalence increased with age.
INTERPRETATION: High anal HPV prevalence among young HIV-positive and HIV-negative MSM highlights the benefits of gender-neutral HPV vaccination before sexual activity over catch-up vaccination. HIV-positive MSM are a priority for anal cancer screening research and initiatives targeting HPV16-positive HSIL+.
FUNDING: International Agency for Research on Cancer.
Direct and indirect effects of climate on richness drive the latitudinal diversity gradient in forest trees

Chu C, Lutz JA, Král K, Vrška T, Yin X, Myers JA, et al.

Ecol Lett, 2019 Feb;22(2):245-255.
PMID: 30548766 DOI: 10.1111/ele.13175

Climate is widely recognised as an important determinant of the latitudinal diversity gradient. However, most existing studies make no distinction between direct and indirect effects of climate, which substantially hinders our understanding of how climate constrains biodiversity globally. Using data from 35 large forest plots, we test hypothesised relationships amongst climate, topography, forest structural attributes (stem abundance, tree size variation and stand basal area) and tree species richness to better understand drivers of latitudinal tree diversity patterns. Climate influences tree richness both directly, with more species in warm, moist, aseasonal climates and indirectly, with more species at higher stem abundance. These results imply direct limitation of species diversity by climatic stress and more rapid (co-)evolution and narrower niche partitioning in warm climates. They also support the idea that increased numbers of individuals associated with high primary productivity are partitioned to support a greater number of species.
Fulltext Arbuscular mycorrhizal trees influence the latitudinal beta-diversity gradient of tree communities in forests worldwide

Zhong Y, Chu C, Myers JA, Gilbert GS, Lutz JA, Stillhard J, et al.

Nat Commun, 2021 May 25;12(1):3137.
PMID: 34035260 DOI: 10.1038/s41467-021-23236-3

Arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) associations are critical for host-tree performance. However, how mycorrhizal associations correlate with the latitudinal tree beta-diversity remains untested. Using a global dataset of 45 forest plots representing 2,804,270 trees across 3840 species, we test how AM and EcM trees contribute to total beta-diversity and its components (turnover and nestedness) of all trees. We find AM rather than EcM trees predominantly contribute to decreasing total beta-diversity and turnover and increasing nestedness with increasing latitude, probably because wide distributions of EcM trees do not generate strong compositional differences among localities. Environmental variables, especially temperature and precipitation, are strongly correlated with beta-diversity patterns for both AM trees and all trees rather than EcM trees. Results support our hypotheses that latitudinal beta-diversity patterns and environmental effects on these patterns are highly dependent on mycorrhizal types. Our findings highlight the importance of AM-dominated forests for conserving global forest biodiversity.

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