Overexpression of a BAHD acyltransferase, OsAt10, alters rice cell wall hydroxycinnamic acid content and saccharification.

Grass cell wall properties influence food, feed, and biofuel feedstock usage efficiency. The glucuronoarabinoxylan of grass cell walls is esterified with the phenylpropanoid-derived hydroxycinnamic acids ferulic acid (FA) and para-coumaric acid (p-CA). Feruloyl esters undergo oxidative coupling with neighboring phenylpropanoids on glucuronoarabinoxylan and lignin. Examination of rice (Oryza sativa) mutants in a grass-expanded and -diverged clade of BAHD acyl-coenzyme A-utilizing transferases identified four mutants with altered cell wall FA or p-CA contents. Here, we report on the effects of overexpressing one of these genes, OsAt10 (LOC_Os06g39390), in rice. An activation-tagged line, OsAT10-D1, shows a 60% reduction in matrix polysaccharide-bound FA and an approximately 300% increase in p-CA in young leaf tissue but no discernible phenotypic alterations in vegetative development, lignin content, or lignin composition. Two additional independent OsAt10 overexpression lines show similar changes in FA and p-CA content. Cell wall fractionation and liquid chromatography-mass spectrometry experiments isolate the cell wall alterations in the mutant to ester conjugates of a five-carbon sugar with p-CA and FA. These results suggest that OsAT10 is a p-coumaroyl coenzyme A transferase involved in glucuronoarabinoxylan modification. Biomass from OsAT10-D1 exhibits a 20% to 40% increase in saccharification yield depending on the assay. Thus, OsAt10 is an attractive target for improving grass cell wall quality for fuel and animal feed.

Clinical phenotype and genetic function analysis of a family with hypomyelinating leukodystrophy-7 caused by POLR3A mutation.

Hypomyelinating leukodystrophy (HLD) is a rare genetic heterogeneous disease that can affect myelin development in the central nervous system. This study aims to analyze the clinical phenotype and genetic function of a family with HLD-7 caused by POLR3A mutation. The proband (IV6) in this family mainly showed progressive cognitive decline, dentin dysplasia, and hypogonadotropic hypogonadism. Her three old brothers (IV1, IV2, and IV4) also had different degrees of ataxia, dystonia, or dysarthria besides the aforementioned manifestations. Their brain magnetic resonance imaging showed bilateral periventricular white matter atrophy, brain atrophy, and corpus callosum atrophy and thinning. The proband and her two living brothers (IV2 and IV4) were detected to carry a homozygous mutation of the POLR3A (NM_007055.4) gene c. 2300G > T (p.Cys767Phe), and her consanguineous married parents (III1 and III2) were p.Cys767Phe heterozygous carriers. In the constructed POLR3A wild-type and p.Cys767Phe mutant cells, it was seen that overexpression of wild-type POLR3A protein significantly enhanced Pol III transcription of 5S rRNA and tRNA Leu-CAA. However, although the mutant POLR3A protein overexpression was increased compared to the wild-type protein overexpression, it did not show the expected further enhancement of Pol III function. On the contrary, Pol III transcription function was frustrated (POLR3A, BC200, and tRNA Leu-CAA expression decreased), and MBP and 18S rRNA expressions were decreased. This study indicates that the POLR3A p.Cys767Phe variant caused increased expression of mutated POLR3A protein and abnormal expression of Pol III transcripts, and the mutant POLR3A protein function was abnormal.

Targeting CDK4/6 in glioblastoma via in situ injection of a cellulose-based hydrogel.

Despite aggressive treatments, including surgery, chemotherapy and radiotherapy, the prognosis of glioblastoma (GBM) remains poor, and tumor recurrence is inevitable. The FDA-approved CDK4/6 inhibitor palbociclib (PB) showed interesting anti-GBM effects, but its brain penetration is limited by the blood-brain barrier. The aim of this project is to find whether the cellulose-based hydrogel via in situ injection could provide an alternative route to PB brain delivery and generate sufficient drug exposure in orthotopic GBM. In brief, PB was encapsulated in a cellulose nanocrystal network structure crosslinked by polydopamine via divalent Cu2+ and hexadecylamine. The formed hydrogel (PB@PH/Cu-CNCs) exhibited sustained drug retention and acid-responsive network de-polymerization for controlled release in vivo. Specifically, the released Cu2+ catalyzed a Fenton-like reaction to generate reactive oxygen species (ROS), which was further enhanced by PB, and consequently, irreversible senescence and apoptosis were induced in GBM cells. Finally, PB@PH/Cu-CNCs demonstrated a more potent anti-GBM effect than those treated with free PB or PH/Cu-CNCs (drug-free hydrogel) in cultured cells or in an orthotopic glioma model. These results prove that the injection of the PB-loaded hydrogel in situ is an effective strategy to deliver the CDK4/6 inhibitor into the brain and its anti-GBM effect can be further enhanced by combining Cu2+-mediated Fenton-like reaction.

Low-dose post-transplant cyclophosphamide with G-CSF/ATG based haploidentical protocol provides favorable outcomes for SAA patients.

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT), as one of the life-saving treatments for severe aplastic anemia (SAA), is widely used because of its great donor availability. Over decades, granulocyte colony-stimulating factor (G-CSF)/antithymocyte globulin (ATG)-based protocol (the so-called Beijing Protocol) has achieved favorable engraftment and survival outcomes. In this study, we modified the conventional Beijing Protocol: the full-dose Cyclophosphamide (Cy) (200 mg/kg in total) was divided into 42.75 mg/kg Cy on day -5 to day -2 and Low dose post-transplant Cy (PTCy) (14.5 mg/kg on days +3 and +4), hoping to reduce the incidence of severe acute graft-versus-host disease (aGVHD) and to guarantee successful and stable engraftment. Here we retrospectively reported and analyzed the data of first 17 patients with SAA who had received haplo-HSCT using this novel regimen between August 2020 and August 2022. The median follow-up was 522 days (range, 138-859 days). No patient developed primary graft failure. Four (23.5%) patients developed grade II bladder toxicity, two (11.8%) patients developed grade II cardiotoxicity. All patients achieved neutrophil and platelet engraftment at median times of 12 days (range, 11-20 days) and14 days (range, 8-36 days). During our follow-up, no patients developed grade III-IV aGVHD. The cumulative incidence of grade II and grade I aGVHD at 100 days was 23.5% (95% CI, 6.8%-49.9%) and 47.1% (95% CI, 23.0%-72.2%). Three patients (17.6%) developed chronic GVHD of skin, mouth, and eyes and all of which were mild. All patients are alive by the end of the follow-up, with a failure-free survival of 100%, which was defined as survival without treatment failures, such as death, graft failure, or relapse rate. The rate of cytomegalovirus (CMV) reactivation was 82.4% (95% CI, 64.3%-100%). The rate of Epstein-Barr virus (EBV) reactivation was 17.6% (95% CI, 3.8%-43.4%). No CMV disease and post-transplantation lymphoproliferative disorder (PTLD) occurred among these patients. In conclusion, the encouraging results of prolonged survival outcomes and reduced incidence of GVHD suggest promising effect of this novel regimen in haplo-HSCT for patients with SAA. Larger-sample prospective clinical trials are needed to confirm the effectiveness of this regimen.

A molecularly imprinted photonic polymer sensor with high selectivity for tetracyclines analysis in food.

A molecularly imprinted photonic polymer (MIPP) sensor for respective detection of tetracycline, oxytetracycline and chlortetracycline is developed based on the combination of a colloidal crystal templating method and a molecular imprinting technique. Colloidal crystal templates are prepared from monodisperse polystyrene colloids. The molecularly imprinted polymer, which is embodied in the colloidal crystal templates, is synthesized with acrylic acid and acrylamide as monomers, N,N'-methylene bisacrylamide as a cross-linker and tetracyclines (TCs) as imprinting template molecules. After removal of the colloidal crystal template and the molecularly imprinted template, the resulted MIPP consists of a three-dimensional, highly ordered and interconnected macroporous array with a thin hydrogel wall, where nanocavities complementary to analytes in shape and binding sites are distributed. The response of MIPP to TCs stimulants in aqueous solution is detected through a readable Bragg diffraction red-shift, which is due to the lattice change of MIPP structures responding to their rebinding to the target TCs molecules. A linear relationship was found between the Δλ and the concentration of TCs in the range from 0.04 µM to 0.24 µM. With this sensory system, direct and selective detection of TCs has been achieved without using label techniques and expensive instruments. The developed method has been applied successfully to detect tetracycline in milk and honey samples.

Reactive oxygen species mediated theranostics using a Fenton reaction activable lipo-polymersome.

Recently, reactive oxygen species (ROS)-induced apoptosis has been widely studied by researchers through various means. Among them, the singlet oxygen produced by the Fenton reaction is particularly effective in killing tumor cells. Although photodynamic therapy (PDT) takes advantage of the spatial-temporal control of ROS production, the design of the Fenton reaction in an ingenious way is still a question worth exploring. Herein, we have designed and prepared a succinic peroxide-filled Fenton reaction activable Pt/Fe3O4@SP-PLGA lipo-polymersome that displays ROS mediated chemodynamic therapy (CDT). The therapeutic element, ˙OH, is generated under NIR irradiation/tumor acidic pH environment through engineering the reaction between succinic peroxide (SP) and iron oxide. Instead of using single endogenous H2O2 or even encapsulation, the conjugation with SP in the Pt/Fe3O4@SP-PLGA lipo-polymersome provides a more stable, high-yielding peroxygen source. The results also showed that after the addition of cisplatin, the amount of ROS production increased significantly. The proof-of-concept design of the Fenton reaction activable Pt/Fe3O4@SP-PLGA lipo-polymersome with enhanced ROS-generation characteristics provides a general approach to afford potent ROS-mediated cancer therapy.

Constituting fully integrated colorimetric analysis system for Fe(III) on multifunctional nitrogen-doped MoO3/cellulose paper.

Using ammonium molybdate and thiourea as precursors, nitrogen-doped MoO3 was produced by a one-step carbonization and then fixed into the cellulose filter paper (NMCP) with acrylic resin as a fixative. NMCP was designed as a multifunctional nanocomposite, i.e., solid phase adsorbent for Fe(III) preconcentration, photocatalyst for iron species transformation and color interference removal, and colorimetric sensor for Fe(III) determination. After photocatalysis, the complex of Fe-humic substances could be transformed into Fe(III) ions, the interference of colored organic matter (e.g., aqueous humic substance) was removed, Fe(III) was enriched selectively onto NMCP with the coexistence of interference metal ions (e.g. Co(II) and Cd(II)) and then transformed into Fe(II) by hydroxylamine and photoreduction and for colorimetric analysis. The obstacle of o-phenanthroline colorimetric method was overcome. The photodegradation activity of MoO3 was improved 2.02 times by nitrogen doping with the optimal mass ratio, which was also 5.11 times of P25-TiO2. The concentration of Fe(III) on NMCP was quantified by the gray-scale using smart phones and image processing software, without complicated equipment. Based on multifunctional NMCP, a fully integrated visual analysis system was proposed and suitable for the field detection of Fe(III) in natural water. The log-linear calibration curve for Fe(III) was in the range of 0.05-5mg/L with a determination coefficient (R2) of 0.976 and detection limit of 15µg/L.

[Surgical treatment of carotid stenosis].

OBJECTIVE: To summarize clinical experience of carotid endarterectomy (CEA) in treating severe carotid stenosis. METHODS: Between October 1998 and January 2010, 215 patients with carotid stenosis were treated with CEA. There were 140 males and 75 females with an average age of 66 years (range, 51-88 years). Transient ischemic attack (TIA) occurred in 127 cases, and 31 cases had history of cerebral infarction. All cases were diagnosed definitely by selective angiography and/or CT angiography, and stenosis degree was more than 80%; contralateral carotid artery was also involved in 45 cases. Ninety-six cases were found to have coronary artery stenosis by coronary angiography. CEA and coronary artery bypass grafting were performed simultaneously in 25 cases. Peripheral arterial disease was found in 43 cases and treated at the same time. RESULTS: A total of 155 patients were followed up 6-72 months. The clinical symptom significantly alleviated in 148 cases postoperatively. Two cases had complication of cerebral hemorrhage within 1 week postoperatively; one died and the other was resumed after the conservative treatment. One case had hypoglossal nerve injury. Four cases had injuring marginal mandibular branch of the facial nerve, and no special treatment was given. Restenosis was found in 25 patients, and the stenosis degree was less than 25%; moreover, the patients had no TIA. One case died of heart attack at 3 years of follow-up period. CONCLUSION: CEA is an effective and safe method for treating severe carotid stenosis.

[Expression of interleukin 2 and IL-2 receptor after implanted tissue engineered bones constructed with allogeneic marrow stromal stem cells and bio-derived materials in rhesus monkeys].

OBJECTIVE: To explore the feasibility of allogeneic marrow stromal stem cells (MSCs) as seed cells to construct tissue engineered bone by detecting the expressions of interleukin 2 (IL-2) and IL-2 receptor in rhesus monkeys after implanting these tissue engineered bones. METHODS: Engineered bones were constructed with osteoblasts which derived from allogeneic MSCs and bio-derived materials in vitro, and then were implanted to bridge 2.5 cm segmental bone defects of left radius in 15 rhesus monkeys as experimental group, bio-derived materials only were implanted to bridge same size defects of right radius as control group. Every 3 monkeys were sacrificed in the 1st, the 2nd, the 3rd, the 6th and the 12th weeks postoperatively and the expressions of IL-2 and IL-2 receptor in blood and graft samples were detected quantitatively by enzyme-linked immunosorbent assay (ELISA). RESULTS: There was no significant difference in the contents of IL-2 and its receptor between 2 groups (P>0.05). The contents of IL-2 and its receptor increased from the 2nd week and maintained high level from the 2nd to the 6th week, but decreased after 6 weeks. CONCLUSION: Tissue engineered bones constructed with allogeneic MSCs and bio-derived materials show low immunogenicity. Allogeneic MSCs may be used as seed cells to construct tissue engineered bone.