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Skin injuries lead to a large burden of morbidity. Although numerous clinical and scientific strategies have been investigated to repair injured skin, optimal regeneration therapy still poses a considerable obstacle. To address this challenge, decellularized extracellular matrix-based scaffolds recellularized with stem cells offer significant advancements in skin regeneration and wound healing. Herein, a decellularized human placental sponge (DPS) was fabricated using the decellularization and freeze-drying technique and then recellularized with human adipose-derived mesenchymal cells (MSCs). The biological and biomechanical properties and skin full-thickness wound healing capacity of the stem cells-DPS constructs were investigated in vitro and in vivo. The DPS exhibited a uniform 3D microstructure with an interconnected pore network, 89.21% porosity, a low degradation rate, and good mechanical properties. The DPS and MSCs-DPS constructs were implanted in skin full-thickness wound models in mice. An accelerated wound healing was observed in the wounds implanted with the MSCs-DPS construct when compared to DPS and control (wounds with no treatment) during 7 and 21 days postimplantation follow-up. In the MSCs-DPS group, the wound was completely re-epithelialized, the epidermis layer was properly organized, and the dermis and epidermis' bilayer structures were restored after 7 days. Our findings suggest that DPS is an excellent carrier for MSC culture and delivery to skin wounds and now promises to proceed with clinical evaluations.

In this study, a Nd 2 O 3 @MIL(Fe)-88A composite was prepared through a hydrothermal method and used to detect dichlorvos. The XRD result demonstrated that the prepared sensor is highly crystalline in nature. The affinity of metal oxide and MIL(Fe)-88A could be utilised to overcome low stability and sensitivity owing to their synergistic and electronic effects. Differential pulse voltammetry (DPV) exhibits the electrocatalytic behaviour of Nd 2 O 3 @MIL(Fe)-88A; it functions at a lower potential at -0.5 to 0.8 V and has a wide linear range of 1-250 nM. It shows a very low detection limit of 0.92 nM with good sensitivity (4.42 mA nM -1 ) and selectivity. The developed Nd 2 O 3 @MIL(Fe)-88A sensor was successfully applied to detect dichlorvos in real analysis. The recovery range calculated for cabbage and orange extracts was 96-97% and 99.5-103.4%, respectively, and RSD% calculated for cabbage and orange extracts was from 1.40 to 3.39% and from 0.64 to 2.26%, respectively., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

In the biomedical sciences, particularly in wound healing, tissue engineering, and regenerative medicine, the development of natural-based biomaterials as a carrier has revealed a wide range of advantages. Tissue engineering is one of the therapeutic approaches used to replace damaged tissue. Polymers have received a lot of attention for their beneficial interactions with cells, but they have some drawbacks, such as poor mechanical properties. Due to their relatively large surface area, nanoparticles can cause significant changes in polymers and improve their mechanical properties. The nanoparticles incorporated into biomaterial scaffolds have been associated with positive effects on cell adhesion, viability, proliferation, and migration in the majority of studies. This review paper discusses recent applications of polymer-nanoparticle composites in the development of tissue engineering scaffolds, as well as the effects of these nanomaterials in the fields of cardiovascular, neural, bone, and skin tissue engineering., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Bone as a minerals' reservoir and rigid tissue of the body generating red and white blood cells supports various organs. Although the self-regeneration property of bone, it cannot regenerate spontaneously in severe damages and still remains as a challenging issue. Tissue engineering offers several techniques for regenerating damaged bones, where various biomaterials are examined to fabricate scaffolds for bone repair. Piezoelectric characteristic plays a crucial role in repairing and regenerating damaged bone by mimicking the bone niche behavior. Piezoelectric biomaterials show significant potential for bone tissue engineering. Herein we try to have a comparative review on piezoelectric and non-piezoelectric biomaterials used in bone tissue engineering, classified them, and discussed their effects on implanted cells and manufacturing techniques. Especially, Polyvinylidene fluoride (PVDF) and its composites are the most practically used piezoelectric biomaterials for bone regeneration. PVDF and its composites have been summarized and discussed to repair damaged bone tissues.

There have been several attempts to find promising biomaterials for skin regeneration, among which polylysine (a homopolypeptide) has shown benefits in the regeneration and treatment of skin disorders. This class of biomaterials has shown exceptional abilities due to their macromolecular structure. Polylysine-based biomaterials can be used as tissue engineering scaffolds for skin regeneration, and as drug carriers or even gene delivery vectors for the treatment of skin diseases. In addition, polylysine can play a preservative role in extending the lifetime of skin tissue by minimizing the appearance of photodamaged skin. Research on polylysine is growing today, opening new scenarios that expand the potential of these biomaterials from traditional treatments to a new era of tissue regeneration. This review aims to address the basic concepts, recent trends, and prospects of polylysine-based biomaterials for skin regeneration. Undoubtedly, this class of biomaterials needs further evaluations and explorations, and many critical questions have yet to be answered., Competing Interests: Michael R. Hamblin declares the following potential conflicts of interest. Scientific Advisory Boards: Transdermal Cap Inc, Cleveland, OH; Hologenix Inc. Santa Monica, CA; Vielight, Toronto, Canada; JOOVV Inc, Minneapolis‐St. Paul MN; USHIO Corp, Japan; Sanofi‐Aventis Deutschland GmbH, Frankfurt am Main, Germany., (© 2021 The Authors. Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)

There has been a recent surge in research on primate infectious disease ecology. Two major areas remain relatively unaddressed to date-the prevalence of enteric bacterial parasites and the role of anthropogenic environmental factors in parasite acquisition in commensally living primate populations. In this preliminary assessment, we address both these gaps by assessing the prevalence, and the role of anthropogenic factors in shaping this prevalence, of three enteric bacterial parasites-E . coli O157:H7, Salmonella sp., Shigella sp.-across populations of rhesus macaques (M. mulatta) that live commensally with humans in Dehradun, northern India. Across 10-week study period, we collected data on (1) human-macaque behavioral interactions, (2) macaque and human demographic and activity scans, and (3) macaque fecal samples from the environment at four different locations in Dehradun. Biochemical tests and morphology-based confirmations clearly established the presence of all three enteric bacterial parasites in rhesus macaques. Overall prevalence ranged from 2 to 5 %, with Shigella sp. being the most prevalent. Regression analyses linking anthropogenic factors to bacterial prevalence showed a positive association between rates of macaques eating human garbage and E. coli O157:H7 (β = 0.23, p = 0.083), but a negative association with Salmonella sp. (β = -0.17, p = 0.026). Rather, the prevalence of Salmonella sp. was positively linked to rates of macaque eating provisioned food (β = 0.0012, p = 0.058). Finally, we found no relationship between anthropogenic factors and the prevalence of Shigella sp. Our findings establish the prevalence of enteric bacterial parasites in commensal populations of primates and suggest that although anthropogenic factors are linked to bacterial prevalence, the nature of the relationships may depend on the socioecological/foraging strategies of macaques and the food sources that facilitate the environmental survival of particular types of enteric bacteria over others.

In this research, after synthesizing poly(L-lactide-co-β-malic acid) (PLMA) copolymer, hybrid particles of ice and nanocrystalline forsterite (NF) as coating carriers were used to prepare NF-coated PLMA scaffolds. The porous NF-coated scaffolds were directly fabricated by a combined technique using porogen leaching and freeze-drying methods. The obtained results indicate that the scaffolds were structurally porous with NF particles on their surfaces. When compared to the uncoated scaffolds, the NF coating improved both mechanical properties as well as enhanced bioactivity of the scaffolds. In addition, in vitro biological response of the rat bone marrow stromal cells indicated that NF significantly increased the biocompatibility of NF-coated scaffolds compared with PLMA., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A novel oligomer p-bromoacetophenone-formaldehyde (OPBAF) was prepared by condensation polymerization in the presence of an acid as catalyst. It was characterized by FT-IR, NMR, pyrolysis GC/MS, XRD, GPC, and TG-DTG. The crystallographic parameters and space group for hexagonal OPBAF were a = b = 2.0810 Å and c = 9.2340 Å and P3̅m1, respectively. The degradation activation energy of the oligomer was studied by the Kissinger method. The kinetic parameters were also obtained. Halogen bonding interactions in the crystalline oligomers are identified between halogen···carbonyl and halogen···halogen. Little correlation was found in the halogen bonding motifs exhibited as a function of bromine present in this oligomer, and a unique bifurcated Br···Br/Br···O═C halogen bonding synthon was identified. This newly developed oligomer may be used as an interesting material for the development of 3D-designed structural products.

Macaques live in close contact with humans across South and Southeast Asia, and direct interaction is frequent. Aggressive contact is a concern in many locations, particularly among populations of rhesus and longtail macaques that co-inhabit urbanized cities and towns with humans. We investigated the proximate factors influencing the occurrence of macaque aggression toward humans as well as human aggression toward macaques to determine the extent to which human behavior elicits macaque aggression and vice versa. We conducted a 3-month study of four free-ranging populations of rhesus macaques in Dehradun, India from October-December 2012, using event sampling to record all instances of human-macaque interaction (N = 3120). Our results show that while human aggression was predicted by the potential for economic losses or damage, macaque aggression was influenced by aggressive or intimidating behavior by humans as well as recent rates of conspecific aggression. Further, adult female macaques participated in aggression more frequently than expected, whereas adult and subadult males participated as frequently as expected. Our analyses demonstrate that neither human nor macaque aggression is unprovoked. Rather, both humans and macaques are responding to one another's behavior. Mitigation of human-primate conflict, and indeed other types of human-wildlife conflict in such coupled systems, will require a holistic investigation of the ways in which each participant is responding to, and consequently altering, the behavior of the other., (© 2015 Wiley Periodicals, Inc.)

Background: Direct tabletting is a need of Pharmaceutical industries. Poor mechanical properties of drug particles require wet granulation which is uneconomical, laborious, and tedious., Objective: Objective of this work was to study influence of various polymers/excipients on formation of directly compressible Crystallo-co-agglomerates (CCA) of water soluble drug Secnidazole (hydroxy-2-propyl)-1-methyl-2-nitro-5-imidazole), an antimicrobial agent., Method: Acetone-petroleum ether system was used to develop CCA of drug in the presence of polymers/excipients. Clarity of the supernatant was considered an endpoint for completion of agglomeration. The prepared CCA were subjected for topographic, micromeritic, mechanical, compressional, and drug release properties., Results: The process yielded ~92 to 98% wt/wt CCA containing secnidazole with the diameter between 0.2 and 0.7 mm. CCA showed excellent flow, packability, compatibility, and crushing strength. Heckel plot showed lower σ(0) and higher tensile strength with lower elastic recovery (0.55-1.28%) of CCA. Dissolution profile of CCA was improved. Differential scanning calorimetry , fourier transform infra-red, and x-ray diffractometry results showed absence of drug-excipient interaction., Discussion: Matrix beads were generated with uniform dispersion of crystallized drug. Excellent flow, packability, and compactability were due to sphericity of agglomerates. Higher crushing strength of CCA was an indication of good handling qualities. Lower σ(0), higher tensile strength, and lower elastic recovery indicated excellent compressibility of agglomerates. Improvement in dissolution profile was due to porous nature of CCA., Conclusion: Excipients and polymers can play a key role to prepare CCA, an excellent alternative to wet granulation process to prepare particles for direct compression.