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A cell membrane is an essential cellular component providing protection against the outer environment. It is also a host for proteins and carbohydrates responsible for, e.g. transporter, receptor, or enzymatic functions. In parallel, the membrane may also be implicated in pathological processes leading, e.g. to the oligomerization of amyloid-forming proteins, a hallmark of i.a. Alzheimer's disease. The increasing need for detailed information on mechanisms driving the amyloid formation and the potential role of cell membranes in the process proves the research on protein-membrane interactions biologically relevant. Considering the potential and limitations of the relatively well established and newly developed methods, this study focused on selecting methods that allow a broad and comprehensive description of interactions between amyloidogenic protein human cystatin C and lipid bilayers. In the first step, dot-blot and ELISA tests were selected as techniques allowing fast screening for protein-ligand interactions. Next, surface plasmon resonance, spectral shift, biolayer interferometry, and switchSENSE® technology were used to determine kinetic parameters and binding constants for interactions between human cystatin C and the selected lipid bilayers. Based on the obtained results we have proposed the most promising candidates for monitoring of interactions and determining affinity between amyloidogenic proteins and membrane mimetics., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Przemyslaw Jurczak reports financial support was provided by National Science Centre Poland. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The stability of proteins in solution poses a great challenge for both technical applications and molecular biology, including neurodegenerative diseases. In this work, a phosphorylated resveratrol material was examined for its anti-aggregation properties in vitro and in vivo . Here, an anti-fibrillation effect could be measured for amyloid beta and human insulin in vitro and general anti-aggregation properties for crude chicken egg white in solution. Using a drosophila fly model for the overexpression of amyloid beta protein, changes in physiological protein aggregation and improved locomotor abilities could be observed in the presence of dietary phosphorylated resveratrol., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In his 1916 land-mark paper "Hydrotropic appearances", Carl Neuberg coined the term "hydrotropy", referring to the solubilisation effect of hydrophobic molecules by small, amphiphilic compounds. In this voluminous work he examines 43 different compounds for their hydrotropic effect and touches on many aspects that later became relevant to hydrotrope science (e.g. applications in pharma, green chemistry, pre-ouzo effect, etc.). Given the significance of his work, it is still widely cited today. However, poor availability and a potential language barrier will severely limit the accessibility for international researchers. Therefore, this translation into the English language seeks to provide access to both, his original thoughts as well as his prolific experimental work on this topic., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Amphiphilic molecules (e.g. hydrotropes) that enhance the solubility of hydrophobic compounds in water are often charged. As a result, such compounds also show specific ion effects. These effects can either strengthen or weaken the solubilisation power of amphiphilic molecules, depending on their degree of ion hydration. They can even prevail and transform an apparent solubilizer into an "anti-hydrotrope", i.e. a salting-out agent. In the present paper, we discuss this subtle balance between specific (Hofmeister) effects exerted by ionic headgroups and the hydrophobicity of the residual compound structure, including the size of the molecule and the presence of electron-withdrawing groups.

Purpose: To describe the first 30 days of rapid adolescent telehealth scale-up in response to the coronavirus (COVID-19) pandemic at a single academic medical center and assess for disparities in visit completion rates by patient characteristics., Methods: Visit outcome and patient demographic data were obtained via electronic health record (EHR) reports. Telehealth visit completion rates were compared by patient characteristics using the chi-square test and t-test. We used zip code data to generate latitude- and longitude-based maps of the range and density of service delivery. Patient cases highlighting challenges and opportunities for adolescent telehealth were summarized., Results: Between March 16 and April 15, 2020, 392 telehealth visits were scheduled in 331 unique patients, with an 82% appointment completion rate. Video visits were conducted for eating disorders (39%), contraception/menstrual disorders (22%), gender-affirming care (17%), general adolescent medicine (15%), HIV treatment (6%), and substance abuse (1%). The majority of telehealth patients were female Caucasian minors with private insurance. There were no significant differences in telehealth visit completion rates by age, sex, gender, or insurance. Patients coded as non-white (African-American, Asian, or other) in the EHR had lower visit completion rates than white patients (p = .003). Telehealth patients were distributed across five states, with the highest concentration in the zip codes nearest to the clinic., Conclusions: Rapid scale-up of telehealth for Adolescent Medicine was achieved at this large academic medical center. Future implementation research is needed to assure telehealth reaches adolescents without widening health disparities., (Copyright © 2020 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Sexual and reproductive health are an integral part of all youths' health and wellbeing, including youth who are transgender and gender-expansive. This article will discuss general approaches to the sexual and reproductive health care of transgender and gender-expansive youth, and review the topics of contraception and menstrual suppression, fertility preservation and family building, and the prevention and treatment of sexually transmitted infections and HIV in this population. Although transgender youth on testosterone therapy often become amenorrheic, ovulation and pregnancy can still occur, and thus all youth on testosterone therapy should be counseled on the potential for pregnancy and have access to effective contraception. Many forms of hormonal contraceptives are both safe and efficacious when used by youth on testosterone therapy. Hormonal contraceptives may also be used to provide menstrual suppression for those experiencing dysphoria from unwanted uterine bleeding. All transgender youth should receive counseling on fertility preservation and reproductive options prior to starting pubertal blockers and/or gender-affirming hormones, therapies that have varying effects on long-term fertility potential. Several different methods of fertility preservation exist, however there are numerous barriers to transgender youth receiving fertility preservation services, and rates of utilization of these services is low. Transgender individuals suffer from a disproportionate burden of HIV compared to their peers-thought to result from stigma, marginalization, and lack of access to appropriate care. All providers caring for youth should be informed about HIV pre-exposure prophylaxis (PrEP) and HIV post-exposure prophylaxis (PEP), which may help to prevent HIV acquisition., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Heparin cofactor II (HCII) is a glycoprotein in human plasma that inhibits thrombin rapidly in the presence of dermatan sulfate or heparin. Unexpectedly, we found that HCII activity in murine plasma is present in two proteins of 68 and 72 kDa. The two proteins have the same N-terminal amino acid sequence, and both react with an antibody raised against the C-terminal nine amino acid residues of murine HCII predicted from the cDNA sequence. Treatment of the two proteins with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase yields a single 54-kDa band. Thus, murine plasma contains two forms of HCII that appear to have identical amino acid sequences but differ in the composition of their N-linked oligosaccharides. HCII cDNA clones isolated from a murine liver library include a 1434 bp open reading frame following the first Met codon, a TAA stop codon, and 580 bp of 3'-untranslated sequence terminating in a poly(A) tail. The amino acid sequence deduced from the cDNA contains the N-terminal sequence of purified murine plasma HCII preceded by a 23-residue hydrophobic sequence presumed to be the signal peptide. The amino acid sequence of murine HCII is 87% identical to that of human HCII, the greatest variability occurring in the N-terminal portion of the protein. Northern blot analysis reveals a 2.3-kb HCII mRNA in murine and human liver, but no HCII mRNA is detectable in heart, brain, spleen, lung, skeletal muscle, kidney, testis, placenta, pancreas, or intestine. Southern blot analysis of restriction fragment length polymorphisms in progeny on interspecific and intersubspecific crosses indicates that mice have a single HCII gene (designated Hcf2), which maps to chromosome 16 between Prm-1 and Igl. The murine HCII gene is approximately 7.1 kb in size and consists of at least four exons and three introns. The intron/exon organization is identical to that of the human HCII gene except at the 5' end, where the murine gene may lack a large intron in the 5'-untranslated region. Our results indicate that HCII is more highly conserved than the human and murine homologues of other serpins such as alpha 1-antitrypsin and alpha 1-antichymotrypsin.

We previously observed that Ser378 in the heparin-binding domain of vitronectin becomes phosphorylated by a protein kinase in plasma upon addition of ATP and divalent cations. We now report that purified plasma vitronectin contains approximately 2.5 mol of phosphate per mol of protein and that vitronectin becomes phosphorylated during biosynthesis in human hepatoma (HepG2) cells. In vitro, rabbit muscle cAMP-dependent protein kinase specifically phosphorylates Ser378 in single-chain (75 kDa) vitronectin but does not phosphorylate the two-chain (65/10 kDa) form cleaved at Arg379. Heparin affects neither the time course nor the extent of phosphorylation of Ser378 at neutral pH. The extent of phosphorylation of Ser378 achieved with cAMP-dependent protein kinase (greater than or equal to 0.3 mol phosphate per mol vitronectin) is greater than that obtainable in plasma and should enable comparisons to be made of the activities of the native and phosphorylated forms.