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Organic small‐molecule fluorophores, characterized by flexible chemical structure and adjustable optical performance, have shown tremendous potential in biosensing. However, classical organic fluorophore motifs feature large overlap between excitation and emission spectra, leading to the requirement of advanced optical set up to filter desired signal, which limits their application in scenarios with simple settings. Here, a series of wavelength‐tunable small‐molecule fluorescent dyes (PTs) bearing simple organic moieties have been developed, which exhibit Stokes shift up to 262 nm, molar extinction coefficients ranged 30,000–100,000 M−1 cm−1, with quantum yields up to 54.8 %. Furthermore, these dyes were formulated into fluorescent nanoparticles (PT‐NPs), and applied in lateral flow assay (LFA). Consequently, limit of detection for SARS‐CoV‐2 nucleocapsid protein reached 20 fM with naked eye, a 100‐fold improvement in sensitivity compared to the pM detection level for colloidal gold‐based LFA. Besides, combined with loop‐mediated isothermal amplification (LAMP), the LFA system achieved the visualization of single copy level nucleic acid detection for monkeypox (Mpox). [ABSTRACT FROM AUTHOR]

Telocytes (TCs) are distinctive interstitial cells due to their characteristic structures and heterogeneity. They are suggested to participate in tissue repair/regeneration. TCs have been identified in many organs of various mammals. However, data on TCs in lower animals are still very limited. In this work, TCs were identified in the myocardium of the bullfrog (Rana catesbeiana) by light and transmission electron microscopy (TEM). The structural relationships between TCs and neighbouring cell types were measured using the ImageJ (FiJi) morphometric software. TCs with slender Tps (telepodes) were located around cardiomyocytes (CMC). TEM revealed TCs with long Tps in the stroma between CMC. The homocellular tight junctions were observed between the Tps. The Tps were also very close to the neighbouring CMC. The distance between Tps and CMC was 0.15 ± 0.08 μm. Notably, Tps were observed to adhere to the periphery of the satellite cells. The Tps and the satellite cells established heterocellular structural connections by tight junctions. Additionally, Tps were frequently observed in close proximity to mast cells (MCs). The distance between the Tps and the MCs was 0.19 ± 0.09 μm. These results confirmed that TCs are present in the myocardium of the bullfrog, and that TCs established structural relationships with neighbouring cell types, including satellite cells and MCs. These findings provide the anatomical evidence to support the note that TCs are involved in tissue regeneration. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID‐19) remains a serious issue, and the role played by meteorological indicators in the process of virus spread has been a topic of academic discussion. Previous studies reached different conclusions due to inconsistent methods, disparate meteorological indicators, and specific time periods or regions. This manuscript is based on seven daily meteorological indicators in the NCEP reanalysis data set and COVID‐19 data repository of Johns Hopkins University from 22 January 2020 to 1 June 2021. Results showed that worldwide average temperature and precipitable water (PW) had the strongest correlation (ρ > 0.9, p < 0.001) with the confirmed COVID‐19 cases per day from 22 January to 31 August 2020. From 22 January to 31 August 2020, positive correlations were observed between the temperature/PW and confirmed COVID‐19 cases/deaths in the northern hemisphere, whereas negative correlations were recorded in the southern hemisphere. From 1 September to 31 December 2020, the opposite results were observed. Correlations were weak throughout the near full year, and weak negative correlations were detected worldwide (|ρ| < 0.4, p ≤ 0.05); the lag time had no obvious effect. As the latitude increased, the temperature and PW of the maximum confirmed COVID‐19 cases/deaths per day generally showed a decreasing trend; the 2020‐year fitting functions of the response latitude pattern were verified by the 2021 data. Meteorological indicators, although not a decisive factor, may influence the virus spread by affecting the virus survival rates and enthusiasm of human activities. The temperature or PW threshold suitable for the spread of COVID‐19 may increase as the latitude decreases. Plain Language Summary: Climate change has altered life's living environment; humans seem to be able to adapt to climate change within a certain range. This adaptability seems to be human talent, but how about a coronavirus? The impact of environmental variables on coronavirus disease (COVID‐19) spread varies between regions. The two meteorological variables that are most likely to affect the distribution of COVID‐19 have significant latitude patterns, which means that in areas with higher climate temperatures, the temperature range for the maximum spread of COVID‐19 is higher, while in areas with lower climate temperatures, the temperature for the maximum spread of COVID‐19 is lower. Perhaps it indicates that the virus also has the ability to adapt to climate change, even more so than humanity. The complete cessation of COVID‐19 pandemic requires everyone's efforts. Key Points: A more than yearlong and global scale analysis showed environmental variables having a possible influence on coronavirus disease (COVID‐19) spreadTemperature and precipitable water had the strongest correlations with COVID‐19 (ρ > 0.9, p < 0.001) than common meteorological indicatorsThe latitude pattern of COVID‐19 may be a key point in the prediction of the next round of its outbreak [ABSTRACT FROM AUTHOR]

Enrofloxacin, a third-generation fluoroquinolone, is a broad-spectrum antimicrobial drug against a lot of veterinary bacterial diseases. However, bactericidal activity of enrofloxacin is concentration-dependent and its poor aqueous solubility and bitter taste limit its development and application. Meanwhile, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), a widely used cyclodextrin analog, is a safe and an effective drug carrier. It forms inclusion complexes with its drug substrates and improves their physiochemical and pharmacokinetic properties. Enrofloxacin was also found to form a stable inclusion complex with HP-β-CD and different research groups have shown improved solubility for enrofloxacin by 32.5%, 9.25 and 165-fold. Our own efforts in this direction resulted in manifold improvement (916-fold) in its solubility compared to the previous studies. It was further shown that pharmaceutical properties, absorption and bioavailability, of enrofloxacin have also been significantly improved by complexation with HP-β-CD. [ABSTRACT FROM AUTHOR]

Over the last 30 years, there have been several methods developed for the synthesis of oligosaccharides, such as combinatorial synthesis, programmable one‐pot glycosylations, pre‐activation‐based chemo‐selective glycosylation strategy, random glycosylation, chemo‐enzymatic processes, and automated platforms. Distinguishing hydroxyl groups in carbohydrate monomers form the crux of oligosaccharides synthesis. The protection of hydroxyl groups stops glycosylation at undesired positions on carbohydrates, but additional steps are required to install and remove the protecting groups. The targeted functionalization of carbohydrates relies mostly on the protection of hydroxyl groups that are not supposed to undergo glycosylation and to leave the hydroxyl group unprotected where the glycosylation should occur. Numerous procedures to avoid or decrease protecting group manipulations have been developed for the synthesis of a single or an oligosaccharide library, such as glycosylation on unprotected or partially protected acceptors, and random glycosylation on unprotected acceptors. In this review, overall approaches for glycosylation on unprotected or partially protected acceptors in the synthesis of oligosaccharides and oligosaccharide libraries are summarized, the glycosylation on unprotected or partially protected carbohydrate acceptors with or without tin or boron mediation, and random glycosylation on unprotected or partially protected acceptors in solution phase or on solid phase are discussed. [ABSTRACT FROM AUTHOR]

Recent studies have reported that T-reg cells are intimately linked with hair follicles in a stage-dependent manner and play an important role in hair follicle cycling and regeneration in murine skin. Further study revealed that T-reg cell's regulation of hair follicle growth is through its preferential expression of the Notch ligand Jagged‐1 (Jag1), which facilitates hair follicle regeneration. However, the role of Jag1 in androgen-suppressed hair growth is yet to be investigated. In addition, although epidermal growth factor (EGF) is a mitogen for cells including skin cells, whether it works synergistically with Jag1 to enhance hair follicle development is unknown. The current study intended to investigate effects of topical application of Jag1 on androgen-suppressed hair growth, and to determine the potential synergistic effect of EGF and Jag1 in this process in vivo. Fifty mice were depilated at the dorsal back area to achieve synchronized anagen development, and randomly divided into five groups with the following topical treatments control for 14 days; testosterone to induce androgenetic alopecia; Jagged1 (testosterone + Jagged1); EGF (testosterone + EGF); and Jagged1 + EGF (testosterone + Jagged1 + EGF). It was found that EGF and Jag1 by itself respectively, did not promote androgen-suppressed hair growth significantly. This stimulating effect was enhanced in the presence of both EGF and Jagged1 (p < 0.05). The hair growth promoting effect was accompanied by better follicle growth, which is associated with increased cell proliferation in the hair follicle and altered the expression of genes that are important in hair follicular cell proliferation and differentiation. Our results provide insights into the therapeutic potential of these peptides for androgenetic alopecia. [ABSTRACT FROM AUTHOR]

Fondaparinux (trade name Arixtra) is a safe and efficacious anticoagulant, and it is chemically related to low-molecular-weight heparins such as enoxaparin. Fondaparinux is a synthetic pentasaccharide, and its synthesis is difficult and expensive. The high cost of fondaparinux thwarts its extensive worldwide usage. Over the last two decades, several research groups and pharmaceutical companies have been interested in finding efficient and practical methods for its synthesis. The present review discusses those strategies and their pros and cons in a comparative account. [ABSTRACT FROM AUTHOR]

Cholic acid and galactose or lactose dual conjugated chitosan derivatives were designed and synthesized as potential anti liver cancer drug carriers, their structures were characterized through proton NMR spectra, elemental analysis, size distribution, zeta potential, and scanning electron microscope image studies. The ability of the dual conjugates to enhance the aqueous solubility of the cancer drug sorafenib was evaluated. The entrapment efficiency (EE%) and drug content (DC%) of sorafenib in the inclusion complexes were measured. The chitosan dual conjugate with cholic acid and galactose was found to be best in enhancing the aqueous solubility of sorafenib. The solubility of sorafenib in water has increased from 1.7 µg/mL to 1900 µg/mL which is equal to 1117-fold increase in its solubility due to the inclusion complex with chitosan conjugate. [ABSTRACT FROM AUTHOR]

Precipitation microphysics over the Tibetan Plateau (TP) remain insufficiently understood, due to the lack of observations and studies. This paper presents a comprehensive investigation of the raindrop size distribution (DSD) for rainfall that happened on the eastern slope of TP in summer. DSD differences between different rain types and under different rain rates are investigated. Confidential empirical relationships between the gamma shape and slope parameters, and between reflectivity and rain rate are proposed. DSD properties in this area are also compared with those in other areas. The results indicate that the stratiform and convective rains contribute to different rain duration and amount, with diverse rainfall macro- and microphysical properties. The rain spectra of two rain types can become broader with higher concentrations as the rain rate increases. DSDs in this area are different to those in other areas. The stratiform DSD is narrower than that in the non-plateau area. The two rain types of this area both have higher number concentrations for 0.437–1.625 mm raindrops than those of the mid-TP. The relationships of shape–slope parameters and reflectivity–rain rate in this area are also different from those in other areas. The rain spectra in this area can produce a larger slope parameter under the same shape parameter than in the mid-TP. The convective rain can produce a smaller rain rate under the same reflectivity. The accuracy proposed reflectivity–rain rate relationship in application to quantitative rainfall estimation is also discussed. The results show that the relationship has an excellent performance when the rain rate exceeds 1 mm h−1. [ABSTRACT FROM AUTHOR]

• Protegrin-1 promoted the viability of porcine granulosa cells. • Transcriptome analysis showed that PG1 regulate genes with GC and ovarian function. • PG1 downregulated many pro-inflammatory genes in porcine GCs. • PG1 may regulate ovarian function through its immunomodulatory activities. Protegrin-1 (PG1) is an antimicrobial peptide (AMP) that has garnered increasing attention due to its potent immune defense activity. Our previous studies demonstrated the ability of PG1 to enhance proliferation and inhibit apoptosis of porcine granulosa cells (GCs) under oxidative stress. GCs play a crucial role in ovary follicular development. However, the specific function and underlying mechanisms of AMP in follicular development still need further elucidation. The present study aimed to comprehensively explore the biological effects of PG1 on porcine GCs using transcriptome profiling by RNA sequencing technology. Isolated GCs were incubated with or without PG1 for 24 h and transcriptome-wide analysis was exerted to identify differentially expressed genes (DEGs). The results of expression analysis revealed 1,235 DEGs, including 242 up-regulated genes and 993 down-regulated genes (|log2 (FoldChange)| > 1; adjusted P -value < 0.05). The expression levels of 7 selected DEGs were validated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) analysis, which was consistent with the RNA-sequencing data. Among the significant DEGs, several genes associated with GC function and ovarian follicle development were identified, such as estrogen receptor 2 (ESR2), growth and differentiation factor 6 (GDF6), cell division cycle 20 homolog (CDC20), Notch3 , ephrin and Eph receptor system, Egl nine homolog 3 (EGLN3), and BCL2 like 14 (BCL2L14). Gene Ontology (GO) analysis revealed that the top three significant GO terms were inflammatory response, defense response, and granulocyte migration. Additionally, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis presented that DEGs were mainly enriched in the immune system, infectious disease, signaling molecules and interaction, and immune disease. Furthermore, Ingenuity Pathway Analysis (IPA) predicted that the top activated pathway was Liver X Receptor (LXR)/ Retinoid X Receptor (RXR) Activation which is known to be associated with female reproduction. Predicted protein–protein interactions (PPIs) analysis identified complement C3 (C3) as the top node with the highest degree of network connection and revealed that DEGs in the sub-networks were involved in cytokine-cytokine receptor interaction, neuroactive ligand-receptor interaction, chemokine signaling pathway, and metabolic process. In conclusion, this study expanded the understanding of the effects of PG1 on porcine GCs at the transcriptomic level and provided a theoretical basis for further investigation into the role of PG1 in immune defense and mammalian ovarian follicular development. [ABSTRACT FROM AUTHOR]

Galactosyl and lactosyl conjugated 6A,6D-bifunctionlized β cyclodextrin derivatives were designed and synthesized as the potential liver cancer drug carriers through SN2 replacement and click reactions in order to increase liver cancer drug’s targeting ability, solubility and stability. The synthetic methods and strategies to obtain the designed compounds were discussed. [ABSTRACT FROM AUTHOR]

Combining advantageous sequences of Alchemia and Sanofi methods of synthesis of Fondaparinux, a more efficient and practical synthetic strategy for the synthesis of corresponding protected pentasaccharide was developed. The protected pentasaccharide was smoothly converted into Fondaparinux in overall high yield (1%). [ABSTRACT FROM AUTHOR]

We investigated the anti-inflammatory effect of trilobatin, the flavonoid isolated from the leaves of Lithocarpus polystachyus Rehd, as well as the underlying molecular mechanisms. Treatment with trilobatin (0.005-5μM) dose-dependently inhibited the lipopolysaccharide (LPS)-induced mRNA expression and secretion of pro-inflammatory cytokines, including tumor necrosis factor α (TNFα), interleukin-1β (IL-1β) and interleukin-6 (IL-6), in RAW 264.7 macrophages. However, no further inhibition was detected when the concentration of trilobatin was increased to 50μM. Western blot analysis confirmed that the mechanism of the anti-inflammatory effect was correlated with the inhibition of LPS-induced inhibitor of nuclear factor-kappa B α (IκBα) degradation and nuclear factor-kappa B (NF-κB) p65 phosphorylation. In addition, trilobatin also showed a significant inhibition of LPS-induced TNFα and IL-6 at both the mRNA and protein levels in a mouse model. Our results suggest that trilobatin potentially inhibits the LPS-induced inflammatory response by suppressing the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]