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Acute and chronic skin wounds due to burns, pressure injuries, and trauma represent a substantial challenge to healthcare delivery with particular impacts on geriatric, paraplegic, and quadriplegic demographics worldwide. Nevertheless, the current standard of care relies extensively on preventive measures to mitigate pressure injury, surgical debridement, skin flap procedures, and negative pressure wound vacuum measures. This article highlights the potential of adipose-, blood-, and cellulose-derived products (cells, decellularized matrices and scaffolds, and exosome and secretome factors) as a means to address this unmet medical need. The current status of this research area is evaluated and discussed in the context of promising avenues for future discovery.

Greige cotton (GC) has attracted interest in recent years as an eco-friendly, functional fiber for use in nonwoven topsheet materials. GC imparts favorable fluid management and sensorial properties associated with urinary liquid transport and indices related to comfort in wearable incontinence nonwovens. Nonwoven GC has material surface polarity, an ambient moisture content, and a lipid/polysaccharide matrix that imparts positive fluid mechanic properties applicable to incontinence management topsheet materials. However, a better understanding of the connection between functionality and compositional aspects of molecular, mechanical, and material property relations is still required to employ structure/function relations beyond a priori design. Thus, this study focuses on the relation of key indices of material fluid and sensorial functions to nonwoven topsheet composition. Greige cotton, polypropylene, bleached cotton, and polyester fiber blends were hydroentangled at 60, 80, and 100 bar. Greige cotton polypropylene and bleached cotton were blended at ratios to balance surface polarity, whereas low percentages of polyester were added to confer whiteness properties. Electrokinetic and contact angle measurements were obtained for the hydroentangled nonwovens to assess surface polarity in light of material composition. Notably, materials demonstrated a relation of hydrophobicity to swelling as determined electrokinetically by Δζ, ζplateau, and contact angles greater than 90°. Subsequently, three blended nonwoven fabrics were selected to assess effects on fluid management properties including topsheet performance indices of rewet, strikethrough, and fluid handling (rate and efficiency of transport to the absorbent core). These materials aligned well with commercial topsheet fluid mechanics. Using the Leeds University Fabric Handle Evaluation System (LUFHES), the nonwovens were tested for total fabric hand. The results of the LUFHES measurements are discussed in light of fiber contributions. Fiber ratios were found to correlate well with improvement in softness, flexibility, and formability. This study provides insights that improves the understanding of the multifunctional properties accessible with greige cotton toward decisions valuable to selecting greige cotton as an environmentally friendly fiber for nonwoven topsheets.

The cyclic tetrapeptide tentoxin and the conformationally related analog [Pro1] tentoxin have been synthesized by a new solution methodology. D, L-3-phenyl-serine was employed as a synthetic precursor to the Z-dehydrophenylalanine substituent. Increased yields of both compounds were obtained when a modified cyclization procedure was employed through ring closure from the N-terminal substituents of N-methylalanine and proline to a C-terminal glycine. Biological activities were determined in a seedling assay used to measure chlorosis induction. Both tentoxin and [Pro1] tentoxin exhibited similar chlorosis inducing activity. Whole leaf extracts of chlorotic, [Pro1] tentoxin-treated seedling leaves lacked active polyphenoloxidase when subjected to electrophoretic analysis. Coupling factor1 (CF1) ATPase isozymes were assayed for ATPase activity in 10μuM-100 μuM solutions of tentoxin and [Pro1] tentoxin. CF1 ATPase inhibition was observed for both tentoxin and [Pro1] tentoxin. Inhibition of a single ATPase isozyme by tentoxin was alleviated at or above 50μuM while [Pro1] tentoxin inhibited two CF1 ATPases at concentrations up to 110μuM. No alleviation of ATPase inhibition was noted for higher concentrations of [Pro1] tentoxin.

Studies on hydrobenzoins : preparation, crystal structure and stability of borate complexes

The peptide bond in the 4-5 position of the cyclic and linear enkephalin analogs H-Tyr-cyclo[-D-Lys-Gly-Phe-L(or D)-Leu-] and H-Tyr-D-Ala-Gly-Phe-L(or D)-Leu-OH was replaced by a thiomethylene ether linkage. Each of the configurational isomers of the cyclic pseudopeptide H-Tyr-cyclo[-D-Lys-Gly-Phe psi [CH2S]L(or D)-Leu-] showed high potency in both the guinea pig ileum and the mouse vas deferens assay and, therefore, had no preference for either mu- or delta-opioid receptors, in contrast to the cyclic parent peptides H-Tyr-cyclo[-D-Lys-Gly-Phe-L(or D)-Leu-] which are mu-receptor selective. The loss of selectivity observed with the cyclic pseudopeptides may be due to the greater flexibility of their 18-membered ring structures as a consequence of the peptide bond substitution. The linear pseudopeptide analogs were both less potent and less delta-receptor selective than their parent compounds. These results indicate that thiomethylene ether peptide bond replacements can have a pronounced effect on the activity profile of peptide hormones and neurotransmitters.

The potential for use of compounds isolated from diverse sources, ranging from microbial to higher plants, has received increasing attention. These natural products represent a vast array of chemistries and mechanisms of action often having the requisite specificities to be ideal herbicides. Tentoxin, a cyclic tetrapeptide, has potent chlorosis activity on a variety of weeds of soybean and corn while not affecting these crops. Investigations into this toxin's mechanism suggest several enzyme target sites for the development of herbicidal analogues, each having the inherent specificity of the parent compound. Structure/activity relationships determined so far may permit a directed synthesis of efficacious analogues. New insights into biosynthesis of the toxin suggest possible means of increasing production to allow economical exploitation of the toxin itself as a herbicide.

A simple method for determination and quantitation of a cyclic peptide mycotoxin, cyclosporin A, in rice is presented. Rice inoculated with Trichoderma polysporum (Link ex Pers.) was extracted with methylene chloride after 4 weeks of incubation. Cyclosporin A was isolated from extracts by using open bed gel filtration column chromatography (LH-20, acetonitrile) and monitored with thin layer chromatography and reverse phase liquid chromatography coelution with a standard. Preliminary thin layer chromatographic methods were developed. Cyclosporin A was detected by iodine and after partial acid hydrolysis by ninhydrin and UV light. A liquid chromatographic method was developed that used a reverse phase disposable cartridge cleanup and isocratic chromatography with a reverse phase octadecylsilica column and a UV detector set at 212 nm. Recovery of cyclosporin A from spiked rice samples (mg/g range) was 85%.

An isomeric series of four leucine-enkephalin analogs containing the thiomethylene ether unit as an amide bond replacement in all positions have been prepared by solid phase methods. The resulting pseudopeptides divulged widely differing retentive behaviors on reversed phase high performance liquid chromatography (HPLC). An analog containing the Pheψ[CH 2 S]Leu dipeptide replacement at the 4–5 position exhibited binding close to the parent, leucine enkephalin; its guinea pig ileum (GPI) activity was the highest of the analous tested. Another compound, Tyrψ[CH 2 S]Gly 1–2 ]-Leu-enkephalin, also displaced 3 H-etorphine well in the binding assay, but caused increased contractions in the GPI assay at low concentrations. The Pheψ[CH 2 S]Leu results are not compatible with the necessity of a β-turn structure for agonist activity in the GPI assay.

Top round, bovine semimembranosus and adductor muscle was selected as a model for isolation of presumptive, low molecular mass (Mr) flavor peptides. The isolation and purification of these peptides (