[Natural Latex Rubber Condom Inspection and Exploratory Research Analysis].

According to the situation of 34 batches of natural rubber latex condoms tested by our center in 2018, the unqualified items in the product inspection items and the exploratory research results of D4 and D5 content in silicone oil lubricants are analyzed. We make recommendations on product technical requirements or standards to strengthen the quality supervision of products.

A Highly Robust Amphibious Soft Robot with Imperceptibility Based on a Water-Stable and Self-Healing Ionic Conductor.

Dielectric elastomer actuators (DEAs) are widely exploited for actuating soft machines and granting soft robots with capability to operate in both underwater and on-land environments is important to make them adapt to more complex situations. Here, a DEA-driven, highly robust, amphibious imperceptible soft robot (AISR) based on an all-environment stable ionic conductive material is presented. A soft, self-healable, all-environment stable ionic conductor is developed by introducing cooperative ion-dipole interactions to provide underwater stability as well as efficient suppression of ion penetration. By tuning molecular structures of the material, a 50-time device lifetime increase compared with unmodified [EMI][TFSI]-based devices and excellent underwater actuating performance is achieved. With the synthesized ionic electrode, the DEA-driven soft robot exhibits amphibious functionality to traverse hydro-terrestrial regions. When encountering damage, the robot shows good resilience and can self-heal underwater and it also exhibits imperceptibility to light, sound, and heat.

[The application of carbohydrate binding module-Thermobifida fusca cutinase fusion protein in polyethylene terephthalate degradation].

With the development of global economy, the dramatically increased production of polyethylene terephthalate (PET) plastics has led to a remarkably increased amount of plastic waste. PET waste can be treated by landfill, incineration, or biodegradation. While landfilling and incineration may cause secondary pollution, biodegradation has since received increased attentions due to its environmental friendliness. Recent studies have indicated that the carbohydrate binding module (CBM) can effectively enhance the binding of PET degrading enzymes to PET, and consequently increasing PET degradation rate. Here we constructed a fusion protein BaCBM2-Tfuc containing the BaCBM2 from Bacillus anthraci and the cutinase Tfuc from Thermobifida fusca, by megaprimer PCR of whole plasmids (MEGAWHOP). Notabaly, the PET film degradation efficiency (at 60 ℃) of BaCBM2-Tfuc was 2.8 times that of Tfuc. This study may provide technical support for constructing fusion proteins capable of efficiently degrading PET.

Superstretchable, yet stiff, fatigue-resistant ligament-like elastomers.

Ligaments are flexible and stiff tissues around joints to support body movements, showing superior toughness and fatigue-resistance. Such a combination of mechanical properties is rarely seen in synthetic elastomers because stretchability, stiffness, toughness, and fatigue resistance are seemingly incompatible in materials design. Here we resolve this long-standing mismatch through a hierarchical crosslinking design. The obtained elastomer can endure 30,000% stretch and exhibit a Young's modulus of 18 MPa and toughness of 228 MJ m-3, outperforming all the reported synthetic elastomers. Furthermore, the fatigue threshold is as high as 2,682 J m-2, the same order of magnitude as the ligaments (~1,000 J m-2). We reveal that the dynamic double-crosslinking network composed of Li+-O interactions and PMMA nanoaggregates allows for a hierarchical energy dissipation, enabling the elastomers as artificial ligaments in soft robotics.

Efficacy of Fe3O4@polydopamine nanoparticle-labeled human umbilical cord Wharton's jelly-derived mesenchymal stem cells in the treatment of streptozotocin-induced diabetes in rats.

Diabetes mellitus (DM) is characterized by the irreversible destruction of insulin-secreting pancreatic ß-islet cells and requires life-long exogenous insulin therapy. Umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have been shown to improve islet function in animal models of diabetes. However, inadequate MSC homing to injured sites has limited their efficacy. Since efficient cell therapy heavily relies on appropriate homing to target tissues, increasing the specificity to the target organ and the extent of homing of the injected WJ-MSCs is paramount to successful clinical outcomes. Therefore, in this study, we synthesized Fe3O4@polydopamine nanoparticle (NP)-labeled MSCs and evaluated their therapeutic efficacy in a clinically relevant rat model of streptozotocin-induced diabetes using an external magnetic field. We found that NPs were successfully incorporated into WJ-MSCs and did not negatively affect stem cell properties. Magnetic targeting of WJ-MSCs contributed to long-term cell retention in pancreatic tissue and improved the islet function of diabetic rats, compared to injection of WJ-MSC alone. In addition, anti-inflammatory effects and the anti-apoptotic capacity of WJ-MSCs appeared to play a major role in the functional and structural recovery of the pancreas. Thus, therapy relying on the magnetic targeting of WJ-MSCs may serve as an effective approach for DM treatment.

Rab7 regulates primary cilia disassembly through cilia excision.

The primary cilium is a sensory organelle that protrudes from the cell surface. Primary cilia undergo dynamic transitions between assembly and disassembly to exert their function in cell signaling. In this study, we identify the small GTPase Rab7 as a novel regulator of cilia disassembly. Depletion of Rab7 potently induced spontaneous ciliogenesis in proliferating cells and promoted cilia elongation during quiescence. Moreover, Rab7 performs an essential role in cilia disassembly; knockdown of Rab7 blocked serum-induced ciliary resorption, and active Rab7 was required for this process. Further, we demonstrate that Rab7 depletion significantly suppresses cilia tip excision, referred to as cilia ectocytosis, which has been identified as required for cilia disassembly. Mechanically, the failure of F-actin polymerization at the site of excision of cilia tips caused suppression of cilia ectocytosis on Rab7 depletion. Overall, our results suggest a novel function for Rab7 in regulating cilia ectocytosis and cilia disassembly via control of intraciliary F-actin polymerization.