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Neurons become more vulnerable to stress factors with age, which leads to increased oxidative DNA damage, decreased activity of mitochondria and lysosomes, increased levels of p16, decreased LaminB1 proteins, and the depletion of the dendritic tree. These changes are exacerbated in vulnerable neuronal populations during the development of neurodegenerative diseases. Glu-Asp-Arg (EDR) and Lys-Glu-Asp (KED), and Ala-Glu-Asp-Gly (AEDG) peptides have previously demonstrated neuroprotective effects in various models of Alzheimer's disease. In this study, we investigated the influence of EDR, KED, and AEDG peptides on the aging of fibroblast-derived induced neurons. We used a new in vitro cellular model of human neuronal aging based on the transdifferentiation of aged dermal fibroblasts from elderly donors into induced cortical neurons. All peptides promote the arborization of the dendritic tree, increasing both the number of primary processes and the total length of dendrites. Tripeptides have no effect on the activity of mitochondria and lysosomes and the level of p16 protein in induced neurons. EDR peptide reduces oxidative DNA damage in induced neurons derived from elderly donor fibroblasts. Short peptides partially protect induced neurons from age-related changes and stimulate dendritogenesis in neurons. They can be recommended for use as neuroprotective agents. [ABSTRACT FROM AUTHOR]

Introduction. Melatonin and serotonin can influence certain aging processes in the ovaries. The main melatonin receptors are represented by types MT1 and MT2. The goal of investigation. Here, we evaluated the expression of genes and synthesis of MT1 and MT2 receptors, as well as serotonin synthesis in the ovaries during ontogenesis. Methods. We analyzed histological material obtained from the ovaries of infants, women of younger and older reproductive age, premenopausal, menopausal, and postmenopausal women. For the analysis of MT1 and MT2 receptors and serotonin expression and synthesis, RT-PCR and immunohistochemistry were used. Results. We found that the synthesis of serotonin, as well as MT1 and MT2 receptors in the ovaries significantly decrease in ontogenesis. The sharpest drop in these molecules was observed in samples obtained from one-year-old infants, as well as from pubescent girls and menopausal women. A statistically significant 2.3–7.6-fold decrease in the expression of MTNR1A and MTNR1B genes in the ovaries was also observed in one-year-old infants, in adolescents, and in middle-aged women. Conclusions. These data are crucial to understanding the fundamental mechanisms of aging of the female reproductive system and the search for molecules predicting its aging. [ABSTRACT FROM AUTHOR]

A type A aortic dissection (TAAD) is a dangerous condition requiring emergency surgery. Due to the similarity of the symptoms of cerebral malperfusion in TAAD and the signs of ischemic stroke, a differential diagnosis of these diseases is not always available. Patients with TAAD after cerebral malperfusion can have a neurological deficit. Thrombolysis is performed in this case. It can worsen the patient's condition and increase the risk of mortality and disability. The aim of the study is to evaluate the new approach to restoring cerebral perfusion during aortic dissection. This approach includes endovascular recanalization and carotid stenting. Methods: Two clinical cases of TAAD complicated by cerebral malperfusion are described. The first patient is 73 years old and was admitted as planned to perform transcatheter aortic valve implantation (TAVI) for grade III aortic stenosis. The patient underwent transcatheter aortic valve implantation (TAVI) on the second day after admission. The second patient is 60 years old and was hospitalized by an ambulance with strong hypertension and ischemia. The surgical correction of aortic dissection was postponed until the neurological status assessment in both patients. Results: The surgery to correct the aorta dissection was deemed inappropriate. The carotid arteries have been reanalyzed, and cerebral perfusion has been restored in a short time in both patients. Conclusion: Acute bilateral internal carotid occlusion is a potentially fatal TAAD outcome. Emergency endovascular recanalization and carotid stenting may be considered one of the few ways to restore cerebral perfusion. [ABSTRACT FROM AUTHOR]

Peptides show high promise in the targeting and intracellular delivery of next-generation biotherapeutics. The main limitation is peptides' susceptibility to proteolysis in biological systems. Numerous strategies have been developed to overcome this challenge by chemically enhancing the resistance to proteolysis. In nature, amino acids, except glycine, are found in L- and D-enantiomers. The change from one form to the other will change the primary structure of polypeptides and proteins and may affect their function and biological activity. Given the inherent chiral nature of biological systems and their high enantiomeric selectivity, there is rising interest in manipulating the chirality of polypeptides to enhance their biomolecular interactions. In this review, we discuss the first examples of up-and-down homeostasis regulation by two enantiomeric drugs: immunostimulant Thymogen (L-Glu-L-Trp) and immunosuppressor Thymodepressin (D-Glu(D-Trp)). This study shows the perspective of exploring chirality to remove the chiral wall between L- and D-biomolecules. The selected clinical result will be discussed. [ABSTRACT FROM AUTHOR]

Background: Spectrum monitoring of the pathogen in spondylitis patients plays a key role in preventing infectious complications of spinal reconstructions in chronic spondylitis (CS) and in the treatment of surgical site infection (SSI). The aim of this study is to characterize the spectrum of SSI pathogens in CS requiring revision surgery. Methods: The primary cohort encompassed 569 surgical patients with infectious CS. In 99 patients (61 men and 38 women) requiring revision surgical interventions due to SSI, continuous microbiological monitoring of the pathogens was conducted. The average age of the patients was 63 ± 14 years. The vast majority of the patients underwent surgery on a set of multilevel (two or more spinal–motor segments) lesions. Lesions of the lumbar spine were more often noted, and lesions of the thoracic, thoracolumbar, and cervical spine sections were less often noted. This study included all patients operated on within the scope of revision spinal reconstructions in connection with the development of infection of the surgical area over the period from January 2018 to December 2022. Inclusion criteria were etiologically verified spondylitis, age of 18 years or older, and follow-up of 6 months or more. Results: The average rate of revision surgery due to SSI was 17.4%. Germ detection from the material of vertebral localization was noted in 48.3% and pathogen strains were isolated in urine in 60.8%, in decubital ulcers in 23.9%, and in hemoculture in 15.2% of all study patients. Aseptic, deep SSI was detected in 10.1%. Gram-positive, multidrug-resistant, and Gram-negative bacteria with extreme resistance prevailed in the microbiological landscape of late SSI, early, and delayed Gram-positive strains without drug resistance. Conclusions: Infectious etiology of spondylitis is associated with a significantly higher frequency of SSI. In the absence of a positive result from bacteriological examination of the vertebral localization material, it is advisable to conduct blood, decubital ulcer discharge, and urine sampling. [ABSTRACT FROM AUTHOR]

Abstract: Spectroscopic (laser-induced luminescence (LIL) and EPR) and catalytic (ethane hydrogenolysis) techniques were used for characterization of the active sites of Pd/Al2O3 catalysts. These techniques have high sensitivity and make it possible to study the catalysts with Pd concentrations as low as 0.02–0.03wt.%. It was found by EPR using spin probes that the electron donor sites of the support are modified by the deposited palladium. It was found by LIL that the Pd deposition has a substantial effect on the state of hydroxyls on the Al2O3 surface. The obtained results indicate that at Pd concentrations 0.5wt.% or lower supported Pd does not form PdO phase. Instead, it is stabilized in the form of atomically dispersed ion clusters. The possible role of the Al2O3 donor sites in stabilization of such clusters is discussed. [Copyright &y& Elsevier]