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Structural analysis of macromolecular complexes within their natural cellular environment presents a significant challenge. Recent applications of solid-state NMR (ssNMR) techniques on living fungal cells and intact plant tissues have greatly enhanced our understanding of the structure of extracellular matrices. Here, we selectively highlight the most recent progress in this field. Specifically, we discuss how ssNMR can provide detailed insights into the chemical composition and conformational structure of pectin, and the consequential impact on polysaccharide interactions and cell wall organization. We elaborate on the use of ssNMR data to uncover the arrangement of the lignin-polysaccharide interface and the macrofibrillar structure in native plant stems or during degradation processes. We also comprehend the dynamic structure of fungal cell walls under various morphotypes and stress conditions. Finally, we assess how the combination of NMR with other techniques can enhance our capacity to address unresolved structural questions concerning these complex macromolecular assemblies. [Display omitted] The advance in solid-state NMR spectroscopy enables the analysis of polysaccharide and protein assemblies in living fungal cells and intact plant tissues at atomic-to-nanometer resolution. In this review, Fernando et al. discuss the most recent conceptual breakthroughs in cell wall structural biology. [ABSTRACT FROM AUTHOR]

Abstract: The two-dimensional phase unwrapping plays an important role in phase measurement applications. This paper proposes a simple but effective method to construct reliable quality maps for two-dimensional quality-guided phase unwrapping. A new group of reliable quality maps based on weighted-phase-gradient is proposed to overcome the shortcomings of traditional phase-gradient quality maps. When a quality map of a wrapped phase image is generated, the weighted gradient information of neighborhood pixels of the wrapped phase image is used to determine the quality of the current pixel. Thus the quality of the wrapped phase data can be accurately reflected in the resulting quality map. In order to evaluate the reliability, effectiveness and advantages of the proposed quality maps, a new performance evaluation model for quality maps is also proposed. Unwrapped results demonstrate that the weighted-phase-gradient-based quality maps are excellent indicators of the phase quality and can be used to retrieve a reliable phase profile in quality-guided phase unwrapping process. [Copyright &y& Elsevier]

To introduce an effective assisted method using the hysteroscopy transmittance test and a Foley catheter to repair previous cesarean scar defect (PCSD) by laparoscopy. A step-by-step explanation of the surgery using video. A university hospital. A young woman with abnormal uterine bleeding. First, we inspected the pelvic cavity and detached the adhesion, opened the uterovesical peritoneal reflection, and pushed down the bladder. Then, the hysteroscopy transmittance test was used to confirm the site and the size of the PCSD. Next, a Foley catheter was inserted into the diverticulum through the cervical canal, and then we removed the diverticulum along the outer edge [1–4]. The myometrium and the serosal layer were sutured continuously with absorbable sutures. At this point, a second hysteroscopy transmittance test was performed to verify the repair effect. Finally, we placed antiadhesive film. The location, size, and boundary of the PCSD can be exactly marked by this method. The operative time was 68 minutes, blood loss was 20mL, and no complications occurred. This surgical method has the following benefits: the resection of the diverticulum is complete, and the suture is exact; it is suitable for patients with a thin diverticulum wall, large diverticulum cavity, and a long duration of bleeding after menstruation; the hysteroscopy transmittance test was used to confirm the site of the PCSD and verify the repair effect; and the Foley catheter can marker the resection site, prevent gas leakage, and stop bleeding by local compression. [ABSTRACT FROM AUTHOR]

Study Objective: To introduce an effective assisted method using the hysteroscopy transmittance test and a Foley catheter to repair previous cesarean scar defect (PCSD) by laparoscopy.Design: A step-by-step explanation of the surgery using video.Setting: A university hospital.Patients: A young woman with abnormal uterine bleeding.Interventions: First, we inspected the pelvic cavity and detached the adhesion, opened the uterovesical peritoneal reflection, and pushed down the bladder. Then, the hysteroscopy transmittance test was used to confirm the site and the size of the PCSD. Next, a Foley catheter was inserted into the diverticulum through the cervical canal, and then we removed the diverticulum along the outer edge [1-4]. The myometrium and the serosal layer were sutured continuously with absorbable sutures. At this point, a second hysteroscopy transmittance test was performed to verify the repair effect. Finally, we placed antiadhesive film.Measurements and Main Results: The location, size, and boundary of the PCSD can be exactly marked by this method. The operative time was 68 minutes, blood loss was 20mL, and no complications occurred.Conclusion: This surgical method has the following benefits: the resection of the diverticulum is complete, and the suture is exact; it is suitable for patients with a thin diverticulum wall, large diverticulum cavity, and a long duration of bleeding after menstruation; the hysteroscopy transmittance test was used to confirm the site of the PCSD and verify the repair effect; and the Foley catheter can marker the resection site, prevent gas leakage, and stop bleeding by local compression. [ABSTRACT FROM AUTHOR]

Plant cell walls contain cellulose embedded in matrix polysaccharides. Understanding carbohydrate structures and interactions is critical to the production of biofuel and biomaterials using these natural resources. Here we present a solid-state NMR study of cellulose and pectin in 13C-labeled cell walls of Arabidopsis wild-type and mutant plants. Using 1D 13C and 2D 13C–13C correlation experiments, we detected a highly branched arabinan structure in qua2 and tsd2 samples, two allelic mutants for a pectin methyltransferase. Both mutants show close physical association between cellulose and the backbones of pectic homogalacturonan and rhamnogalacturonan-I. Relaxation and dipolar order parameters revealed enhanced microsecond dynamics due to polymer disorder in the mutants, but restricted motional amplitudes due to tighter pectin-cellulose associations. These molecular data shed light on polymer structure and packing in these two pectin mutants, helping to elucidate how pectin could influence cell wall architecture at the nanoscale, cell wall mechanics, and plant growth. • Pectin structure and cellulose packing were assessed using solid-state NMR. • Two pectin mutants, tsd2 and qua2 , were compared to wild-type Arabidopsis. • In these mutants, arabinan content is increased, with a higher degree of branching. • Mutants show tighter packing between cellulose and pectic backbones (HG and RG-I). • The motion of HG and RG-I is faster in the mutants, but with smaller amplitudes. [ABSTRACT FROM AUTHOR]

• A new biomimetic tumor targeting drug delivery system was established. • DOX/Au@Pt-M-NPs can be used for the combined chemo/photothermal therapy of cancer. • DOX/Au@Pt-M-NPs achieved higher drug loading than previous drug delivery systems. • DOX/Au@Pt-M-NPs can reduce oxidative stress damage caused by chemotherapy drugs. [Display omitted] The emergence of the biomimetic nano-drug delivery system provides a feasible way for the clinical treatment of cancer. Noble metal nanomaterials often possess unique and intriguing physicochemical properties, optical properties, electromagnetic properties and catalytic properties, therefore have broad applications in the field of biomedicine. In this work, the porous Au@Pt bimetallic nanoparticles were synthesized via the blending of the chloroauric acid (a gold precursor) with the potassium chloroplatinate (a platinum precursor) at the ratio of 1:1. These Au@Pt NPs exhibited decent catalytic properties, high drug loading capacity (32.3%) and high photothermal conversion efficiency (44.1%). Based on the resultant Au@Pt NPs, a cell membrane-coated photothermal nano-drug delivery system (i.e. the DOX/Au@Pt-M-NPs) was formulated by loading the Doxorubicin (DOX) onto the Au@Pt nanoparticles, which showed a stronger inhibitory effect on tumor cells. The use of the HeLa tumor cell membrane coating demonstrated significantly reinforcing effect on the absorption of the DOX/Au@Pt-M-NPs by tumor cells because of homologous targeting. The cytotoxicity and apoptosis rate of the DOX/Au@Pt-M-NPs group (73.4%) were significantly higher than that of the Au@Pt group (49%). In addition, the damage to major organs caused by the DOX/Au@Pt-M nanoparticle group was significantly lower than that by the DOX/Au@Pt nanoparticle group and the pure DOX group. Taken together, our work demonstrated that nanomedicine carriers camouflaged by tumor cell membranes combined with photothermal therapy and chemotherapy would have potential use in clinical tumor treatment. [ABSTRACT FROM AUTHOR]