Overexpression of PtrMYB121 Positively Regulates the Formation of Secondary Cell Wall in Arabidopsis thaliana.

MYB transcription factors have a wide range of functions in plant growth, hormone signaling, salt, and drought tolerances. In this study, two homologous transcription factors, PtrMYB55 and PtrMYB121, were isolated and their functions were elucidated. Tissue expression analysis revealed that PtrMYB55 and PtrMYB121 had a similar expression pattern, which had the highest expression in stems. Their expression continuously increased with the growth of poplar, and the expression of PtrMYB121 was significantly upregulated in the process. The full length of PtrMYB121 was 1395 bp, and encoded protein contained 464 amino acids including conserved R2 and R3 MYB domains. We overexpressed PtrMYB121 in Arabidopsis thaliana, and the transgenic lines had the wider xylem as compared with wild-type Arabidopsis. The contents of cellulose and lignin were obviously higher than those in wild-type materials, but there was no significant change in hemicellulose. Quantitative real-time PCR demonstrated that the key enzyme genes regulating the synthesis of lignin and cellulose were significantly upregulated in the transgenic lines. Furthermore, the effector-reporter experiment confirmed that PtrMYB121 bound directly to the promoters of genes relating to the synthesis of lignin and cellulose. These results suggest that PtrMYB121 may positively regulate the formation of secondary cell wall by promoting the synthesis of lignin and cellulose.

In Vitro Cytotoxicity of Antiresorptive and Antiangiogenic Compounds on Oral Tissues Contributing to MRONJ: Systematic Review.

BACKGROUND: Invasive dental treatment in patients exposed to antiresorptive and antiangiogenic drugs can cause medication-related osteonecrosis of the jaw (MRONJ). Currently, the exact pathogenesis of this disease is unclear. METHODS: In March 2022, Medline (Ovid), Embase (Ovid), Scopus, and Web of Science were screened to identify eligible in vitro studies investigating the effects of antiresorptive and antiangiogenic compounds on orally derived cells. RESULTS: Fifty-nine articles met the inclusion criteria. Bisphosphonates were used in 57 studies, denosumab in two, and sunitinib and bevacizumab in one. Zoledronate was the most commonly used nitrogen-containing bisphosphonate. The only non-nitrogen-containing bisphosphonate studied was clodronate. The most frequently tested tissues were gingival fibroblasts, oral keratinocytes, and alveolar osteoblasts. These drugs caused a decrease in cell proliferation, viability, and migration. CONCLUSIONS: Antiresorptive and antiangiogenic drugs displayed cytotoxic effects in a dose and time-dependent manner. Additional research is required to further elucidate the pathways of MRONJ.

Preparation, physicochemical characteristics and bioavailability studies of an atorvastatin hydroxypropyl-beta-cyclodextrin complex.

The aim of this study was to improve the solubility, stability and bioavailability of amorphous atorvastatin calcium (AT) by complexing it with hydroxypropyl-beta-cyclodextrin. The formation of the inclusion complexation was identified by molecular modeling, phase solubility diagrams, differential scanning calorimetry and X-ray powder diffractometry. Orally Disintegrating Tablets (ODT) were then manufactured by direct compression. Apart from improved stability compared to pure AT, disintegration time of 27s, hardness of 5 kg and favorable mouth feel were achieved. In vitro dissolution tests of the ODT of AT inclusion complex exhibited higher dissolution rates than those with pure drug and the commercial tablet Lipitor. In vivo bioavailability studies in rats also showed shorter T(max), higher C(max) and increased AUC of 4.42 and 1.86 fold compared to the plain drug ODT and Lipitor. These results strongly suggest to use HP-beta-CD to improve the physicochemical characteristics and bioavailability of AT.

The Clinical and Epidemiological Study of Children with Hand, Foot, and Mouth Disease in Hunan, China from 2013 to 2017.

Hand, foot, and mouth disease (HFMD) is endemic in the Pacific region, especially in mainland China. The case-fatality ratio of HFMD is increasing steadily. Knowledge of the changing epidemiology of HFMD in different regions is necessary for implementing appropriate intervention strategies. In this study, we describe the clinical and epidemiological characteristics of HFMD in Hunan Children's Hospital between 2013 and 2017. A total of 7203 patients with HFMD were admitted, with complication and mortality rates of 35.62% and 0.78%, respectively. The total number of children with HFMD, proportion of severely ill children, and HFMD mortality rate were the highest in 2014. The number of cases caused by EV-A71 and CV-A16 decreased continuously, while the number of cases caused by 'other enteroviruses' increased yearly since 2014, suggesting that other enteric viruses will gradually replace EV-A71 and CV-A16 as the main pathogenic HFMD agents. Furthermore, EV-A71 and mixed infections accounted for the high case fatality rates in children with severe HFMD, among whom EV-A71 infection resulted in the highest complication and mortality rates; the mild form of the disease was dominated by 'other enteroviruses'. In conclusion, the changing etiological pattern highlights the need to improve pathogen surveillance and vaccine strategies for HFMD control.

Thermosensitive and mucoadhesive in situ gel based on poloxamer as new carrier for rectal administration of nimesulide.

Poloxamer 407 has excellent thermo-sensitive gelling properties. Nevertheless, these gels possess inadequate poor bioadhesiveness and high permeability to water, which limited its' application as a thermoresponsive matrix. The main aim of the present investigation was to develop thermosensitive and mucoadhesive rectal in situ gel of nimesulide (NM) by using mucoadhesive polymers such as sodium alginate (Alg-Na) and HPMC. These gels were prepared by addition of mucoadhesive polymers (0.5%) to the formulations of thermosensitive gelling solution containing poloxamer 407 (18%) and nimesulide (2.0%). Polyethylene glycol (PEG) was used to modify gelation temperature and drug release properties. The gelation temperature and drug release rate of the prepared in situ gels were evaluated. Gelation temperature was significantly increased with incorporation of nimesulide (2.0%) in the poloxamer solution, while the addition of the mucoadhesive polymers played a reverse role on gelation temperature. The addition of PEG polymers increased the gelation temperature and the drug release rate. Among the formulations examined, the poloxamer 407/nimesulide/sodium alginate/PEG 4000 (18/2.0/0.5/1.2%) exhibited the appropriate gelation temperature, acceptable drug release rate and rectal retention at the administration site. Furthermore, the micrographic results showed that in situ gel, given at the dose of 20mg/kg, was safe for no mucosa irritation. In addition, it resulted in significantly higher initial serum concentrations, C(max) and AUC of NM compared to the solid suppository.