bluuebunny/crossref_metadata_2025 huggingface dataset:
LPMO‐like Activity of Bioinspired Copper Complexes: From Model Substrate to Extended Polysaccharides
Authors: Leblay Rébecca , Delgadillo‐Ruíz Rafael , Decroos Christophe , Hureau Christelle , Réglier Marius , Castillo Ivan , Faure Bruno , Simaan A. Jalila
Published: September 2023

Polysaccharide oxidative depolymerization is highly desirable to achieve recalcitrant biomass valorization. Inspired by recently discovered Lytic Polysaccharide Monooxygenases, mononuclear copper complexes have been prepared and studied in the literature. However, the activities were evaluated on different substrates and under various conditions. In this work we intended to establish a robust and reproducible activity assay, in aqueous solution at a pH close from neutrality and under mild conditions. We have evaluated several complexes on substrates of increasing complexity: the model substrate para‐nitrophenyl‐β‐D‐glucopyranoside (p‐NPG), cellobiose (glucose dimer), as well as on extended substrates (chitin, cellulose and bagasse from agave). The different assays were compared and proof‐of‐concept that bioinspired complexes can oxidatively promote polysaccharide depolymerization was obtained. Finally, we measured level of hydroxyl radicals released by the complexes under comparable experimental conditions and mechanistic pathways are discussed.
Fluorogen‐Functionalized Mesoporous Silica Hybrid Sensing Materials: Applications in Cu2+ Detection
Authors: Xu Lijie , Jiang Xiaoping , Liu Yuhong , Liang Kang , Gao Meng , Kong Biao
Published: September 2023

Since Cu2+ ions play a pivotal role in both ecosystems and human health, the development of a rapid and sensitive method for Cu2+ detection holds significant importance. Fluorescent mesoporous silica materials (FMSMs) have garnered considerable attention in the realm of chemical sensing, biosensing, and bioimaging due to their distinctive structure and easily functionalized surfaces. As a result, numerous Cu2+ sensors based on FMSMs have been devised and extensively applied in environmental and biological Cu2+ detection over the past few decades. This review centers on the recent advancements in the methodologies for preparing FMSMs, the mechanisms underlying sensing, and the applications of FMSMs‐based sensors for Cu2+ detection. Lastly, we present and elucidate pertinent perspectives concerning FMSMs‐based Cu2+ sensors.
Good Practices and Practical Considerations for Research with Perfluoroalkyl Substances
Authors: Taylor Chloe M. , Breadmore Michael C. , Kilah Nathan L.
Published: September 2023

Per‐ and polyfluoroalkyl substances (PFAS) are a class of hazardous pollutant that are ubiquitous in our modern world. Current research is driven by an increased awareness and concern regarding the safety of PFAS for the general population, while tightening regulations have prompted the need for detection and quantification techniques from a wide range of matrices. PFAS are a group of molecules offering unique behaviours, hazards, and complications that are not obvious or readily apparent from reading the literature. These peculiarities can impede or convolute analyses when not considered in experimental design. Drawing on the knowledge of a range of literature sources, this tutorial review looks to highlight and amalgamate the valuable suggestions and methodologies currently available to enable successful PFAS research in any laboratory.
Acyclic Cucurbit[n]urils: Effective Taste Masking Nanocontainers for Cationic Bitter Compounds
Authors: Peng Wen‐Chang , Lei Zhuo , Lin Qi‐Han , Wu Yan , Yang Jing‐Yu , Wang Hui , Zhou Wei , Zhang Dan‐Wei , Li Zhan‐Ting , Ma Da
Published: September 2023

New acyclic cucurbit[n]urils (ACBs) with eight carboxylate groups were synthesized. These hosts are highly soluble in water, and can form stable inclusion complexes with cationic bitter compounds. ACBs are confirmed to be non‐toxic and biocompatible. Two‐bottle preference (TBP) tests on mice show that all ACBs are tasteless to mammals. ACBs are discovered to mask the bitterness of berberine and denatonium benzoate, but not quinine hydrochloride, due to different binding modes.
Higher‐Order Electrocyclizations in Biological and Synthetic Processes
Authors: de Cózar Abel , Arrieta Ana , Arrastia Iosune , Cossío Fernando P.
Published: September 2023

In general, electrocyclizations follow the Woodward‐Hoffmann's rules of conservation of orbital symmetry. These rules have been extensively verified in low‐order processes, both in thermal and photochemical reactions, up to eight π‐electrons. However, when the number of π‐electrons in the system increases, some deviations of that general rules can be found. This focused review highlights the main features of reported higher‐order electrocyclizations involving 10, 12, 14, 16 and 18 π‐electrons. Some of these examples constitute useful intermediates in the synthesis of biologically active compounds. When computational studies were not included in the reported examples, DFT calculations have been performed to be included in this review. Analysis of the respective pericyclic topologies shows the importance of computational tools for understanding the selectivity observed experimentally.
Calling Cards: A Customizable Platform to Longitudinally Record Protein‐DNA Interactions Over Time in Cells and Tissues
Authors: Yen Allen , Mateusiak Chase , Sarafinovska Simona , Gachechiladze Mariam A. , Guo Juanru , Chen Xuhua , Moudgil Arnav , Cammack Alexander J. , Hoisington‐Lopez Jessica , Crosby MariaLynn , Brent Michael R. , Mitra Robi D. , Dougherty Joseph D.
Published: September 2023

Calling Cards is a platform technology to record a cumulative history of transient protein‐DNA interactions in the genome of genetically targeted cell types. The record of these interactions is recovered by next‐generation sequencing. Compared with other genomic assays, readouts of which provide a snapshot at the time of harvest, Calling Cards enables correlation of historical molecular states to eventual outcomes or phenotypes. To achieve this, Calling Cards uses the piggyBac transposase to insert self‐reporting transposon “Calling Cards” into the genome, leaving permanent marks at interaction sites. Calling Cards can be deployed in a variety of in vitro and in vivo biological systems to study gene regulatory networks involved in development, aging, and disease. Out of the box, it assesses enhancer usage but can be adapted to profile‐specific transcription factor (TF) binding with custom TF‐piggyBac fusion proteins. The Calling Cards workflow has five main stages: delivery of Calling Cards reagents, sample preparation, library preparation, sequencing, and data analysis. Here, we first present a comprehensive guide for experimental design, reagent selection, and optional customization of the platform to study additional TFs. Then, we provide an updated protocol for the five steps, using reagents that improve throughput and decrease costs, including an overview of a newly deployed computational pipeline. This protocol is designed for users with basic molecular biology experience to process samples into sequencing libraries in 2 days. Familiarity with bioinformatic analysis and command line tools is required to set up the pipeline in a high‐performance computing environment and to conduct downstream analyses. © 2023 Wiley Periodicals LLC.

This article was corrected on 16 October 2023. See the end of the full text for details.

Basic Protocol 1: Preparation and delivery of Calling Cards reagents

Support Protocol 1: Next‐generation sequencing quantification of barcode distribution within self‐reporting transposon plasmid pool and adeno‐associated virus genome

Basic Protocol 2: Sample collection and RNA purification

Support Protocol 2: Library density quantitative PCR

Basic Protocol 3: Sequencing library preparation

Basic Protocol 4: Library pooling and sequencing

Basic Protocol 5: Data analysis
Fabrication Technique of Micropatterned Inverse Photonic Crystal Films
Authors: Ashurov Matin , Liu Yuchen , Ezhov Alexander , Din Salah Ud , Baranchikov Alexander , Klimonsky Sergey
Published: September 2023

A simple and frugal method for fabricating inverse micropatterned photonic crystal (PhC) films aimed at miniaturization and multiplexing of opaline PhCs is described. First, highly uniform micropatterned synthetic opal structures in the form of periodic stripes are formed via stick‐slip motion of the meniscus during SiO2 colloid solution evaporation. The prepared opal structures are then used as templates to produce inverse stripe patterned films with highly uniform colors via photopolymerization of ethoxylate trimethylolpropane triacrylate (ETPTA) photocurable resin. Local reflectance spectra are recorded to prove the PhC properties of the inverse stripes, and peaks over 40% associated with the first photonic stop band are observed. The readily fabrication process suggested here is an important step toward the development of many applications that can pave the technical road map for the next wave of innovations and breakthrough in PhCs for sensing. In particular, the resulting structures can be used as PhC arrays containing a line of periodically repeating sensor strips capable to detect the content of alcohols in water.
Determination of chlorphenesin in cosmetics, a preservative that can affect anti‐doping test result interpretations
Authors: Lu Yi‐Wen , Chan Kuei‐Hui , Wu Yu‐Tse , Chang William Chih‐Wei
Published: September 2023

Chlorphenesin is a legitimate preservative commonly used in cosmetics. It shares one urinary metabolite of 4‐chlorophenoxyacetic acid with meclofenoxate, a prohibited stimulant in sports. Recently, there have been cases where athletes using chlorphenesin‐containing products were falsely identified as users of meclofenoxate. This study developed and validated a liquid chromatography method with diode‐array detection to determine the chlorphenesin content in 61 selected personal care products with various functions (e.g., facial care, body cleansing, sun protection, make‐up, hairstyling, perfume, and oral cleaning). The analytical method demonstrated fit‐for‐purpose quantitation and provided good linearity, precision, accuracy, and recovery for analyzing different cosmetic matrices. Among the 27 cosmetics labeled with chlorphenesin, the chlorphenesin concentrations ranged from 0.10 to 2.67 mg/g, with three products showing no detection. None of the products exceeded the maximum limit of 3 mg/g (0.3%) set by regulatory authorities. Among the 34 cosmetics not labeled with chlorphenesin, none of them contained chlorphenesin. This study confirmed the absence of undeclared chlorphenesin in the selected cosmetics, supporting the correctness of chlorphenesin labeling in cosmetics sold in Taiwan. Further investigations studying urinary excretion patterns after different types, doses, frequencies, and sites of cosmetics applications could contribute to strengthen current testing approaches in anti‐doping.
Fundamental experiment and numerical simulation of pre‐ionized inert gas plasma MHD electrical power generation
Authors: Kimsor Ork , Kodera Yoshinobu , Okuno Yoshihiro
Published: September 2023

The experiments of pre‐ionized inert gas plasma MHD electrical power generation are conducted, and the performance and plasma behavior in the experimental generator are examined through time‐dependent r‐_ two‐dimensional numerical simulation. In the experiment, an enthalpy extraction ratio of 4.01% has been obtained with a disk‐shaped MHD generator with radio‐frequency pre‐ionization. In the numerical simulation, at an assumed inlet electron temperature around 5600 K (inlet ionization degree 0:10 × 10−4)_6600 K (1:36 × 10−4), the plasma structure is similar to the non‐uniform structure observed in the experiment. An enthalpy extraction ratio around 2_5% matches well with that in the experiment. At a suitable inlet electron temperature of 7000 K (3:15 × 10−4)_8000 K (1:79 × 10−3), although non‐uniform plasma structure still occurs, a high enthalpy extraction ratio over 10% is expected.
A Hydrophobic Deep Eutectic Solvent for Nuclear Fuel Cycle: Extraction of Actinides and Dissolution of Uranium Oxide
Authors: Gamare Jayashree , Vats Bal Govind
Published: September 2023

Hydrophobic Deep Eutectic Solvents (DESs) have been attracting attention for metal ion extraction in solvent extraction process due to their favorable properties. A Trioctyl phosphine oxide (TOPO) and Thenoyl trifluoroacetone (HTTA) based hydrophobic DES was synthesized and characterized by FTIR and NMR spectroscopy. Actinide ions ( UO22+, Pu4+ and Am3+) and Eu3+ ion extraction was carried out using the DES which shows that it extracts these metal ions from aqueous nitric acid medium depending upon the molarity of nitric acid. At higher molarity of nitric acid (>5 M) the extraction becomes insignificant only for trivalent metal ions and open up the possibility to selectively strip trivalent metal ions from tetravalent and hexavalent ions. This DES was also used for dissolution of uranium oxide (UO3). The dissolution kinetics was studied and it was shown that oxide was dissolved within an hour at 80 °C. The maximum solubility of UO3 in DES was measured and found to be 130±5 mg/mL which is one of the highest reported solubility of UO3 in ILs and DES. The species of uranium which is formed in situ in DES was ascertained to be UO2(TTA)2.TOPO after dissolution of UO3 as supported by FTIR and NMR (1H and 31P) investigations.
Cellular Mechanistic Considerations on Cytotoxic Mode of Action of Phosphino Ru(II) and Ir(III) Complexes
Authors: Wojtala Daria B. , Komarnicka Urszula K. , Kyzioł Agnieszka , Kozieł Sandra , Szmitka Magdalena , Słowikowski Mateusz , Kulczyńska Julia , Stochel Grażyna
Published: September 2023

Two piano‐stool ruthenium(II) complexes Ru(η6‐p‐cymene)Cl2PPh2CH2OH (RuPOH) and Ru(η6‐p‐cymene)Cl2P(p‐OCH3Ph)2CH2OH (RuMPOH) and two half‐sandwich iridium(III) complexes Ir(η5‐Cp*)Cl2PPh2CH2OH (IrPOH) and Ir(η5‐Cp*)Cl2P(p‐OCH3Ph)2CH2OH (IrMPOH) have been studied in terms of potential anticancer activity on previously selected cell line (human lung adenocarcinoma). Based on experimental results obtained in monoculture in vitro model mechanistic considerations on the possible cellular modes of action have been carried out. ICP‐MS analysis revealed the higher cellular uptake for less hydrophobic Ir(III) complexes in comparison to the corresponding Ru(II) compounds. Cytometric analysis showed a predominance of apoptosis over the other types of cell death for all complexes. The apoptotic pathway was confirmed by a decrease in mitochondrial membrane potential and the activation of caspases‐3/9 for both Ru(II) and Ir(III) complexes. It was concluded that in the case of Ru(II) complexes the intense ROS generation is mainly responsible for the resulting cytotoxicity. The corresponding Ir(III) complexes trigger simultaneously at least three different cytotoxic pathways i. e., depletion of mitochondrial potential, activation of caspases‐dependent apoptosis, and ROS‐associated oxidation. Thus, it can be assumed that the final accumulation of toxic effects over time via parallel activation of different pathways results in the highest cytotoxicity in vitro exhibited by Ir(III) complexes when compared with Ru(II) complexes.
Market research of infant formula milks in Spain
Authors: Albertos Irene , Romero Janira , Piqueras‐Picón Alicia , García Sara , López María , Jiménez José María , Alija María José Castro
Published: September 2023

There are circumstances in which breastfeeding is not possible and formula milk feeding has to be resorted to. In these cases, it is difficult to choose among the multitude of brands on the market for infant feeding. Although the composition of formula milk is largely regulated by legislation, there are certain nutrients whose presence in breast milk is beneficial. This circumstance will help us to establish some criteria to choose formula milk for a healthy infant. Among all the formula milks which can be found in different shops (pharmacies, supermarkets, etc.), market research has been carried out based on the nutritional criteria: the lipid and protein profile, certain carbohydrates, amino acids, and vitamins, as well as the presence of nucleotides, prebiotics, and probiotics. Based on these results, it can be established which formula milk we would give to a healthy infant. Thus, within the analyzed formula milks, it has been concluded that the most complete milk in this would be formula milk D and the least formula milk J. Although more studies are needed to confirm this, it is foreseeable that, as the scientific evidence is greater, the legislation will be updated and considering these nutrients for a correct formula milk.
Can technical indicators based on underlying assets help to predict implied volatility index
Authors: Yafeng Shi , Shi Yanlong , Tingting Ying
Published: September 2023

Given the widespread use of technical analysis and the tight relationship between derivatives and the underlying assets, we employ the copula approach to investigate whether the technical indicators based on underlying assets convey extra information about the future movements of implied volatility (IV) indexes. The empirical results, based on long samples of five well‐known IV indexes, suggest that although the technical indicators are not informative for forecasting the future prices of IV indexes, they can provide extra information about the size of forecasting errors of the IV indexes. The findings are also robust to the impact of COVID‐19. The technical indicators are then used to extend Threshold ARCH and Exponencial GARCH models for improving the estimation of Value at Risks (VaRs). The out‐of‐sample forecast results show that the proposed model outperforms the benchmark in estimating the VaRs. These findings have implications for pricing options of IV indexes and managing the risks of IV‐related portfolios.
Rapid Synthesis of Propargyl‐γ‐Modified Peptide Nucleic Acid Monomers for Late‐Stage Functionalization of Oligomers
Authors: López‐Tena Miguel , Watson Emma E. , Romanens Patrick , Winssinger Nicolas
Published: September 2023

The exceptional hybridization properties of peptide nucleic acids (PNAs) coupled with the ease of their synthesis has made this artificial nucleic acid mimetic a desirable platform for diagnostics, therapeutics and supramolecular engineering. PNA backbone modifications have been extensively explored to finetune physicochemical properties and for conjugation of functional molecules. Here, we detail the synthesis of a universal γ‐propargyl‐PNA backbone from serine, and its acylation with the four DNA canonical nucleobases. The availability of serine as d or l enantiomer provide simple accesses to PNA oligomers for hybridization with natural oligonucleotides or for orthogonal hybridization circuitry. We show that late‐stage conjugation enables optimization of the physicochemical properties. This approach is appealing due to its orthogonality to Fmoc‐SPPS, its flexibility and ease for introducing diversity by on‐resin copper(I)‐catalyzed azide‐alkyne cycloaddition (CuAAC). We exemplified the utility of these novel monomers with PNA based hybridization chain reactions (HCRs).
Comparison of autologous, matched sibling, and alternative donor stem cell transplant outcomes for acute myeloid leukemia patients in first remission: A propensity score matching study
Authors: Wang Mingyang , Zhang Haixiao , Zheng Xinhui , Liu Jia , Wang Jiali , Cao Yigeng , Zhang Xiaoyu , Zhang Rongli , Chen Xin , Zhai Weihua , Ma Qiaoling , Wei Jialin , Huang Yong , Yang Donglin , He Yi , Pang Aiming , Feng Sizhou , Han Mingzhe , Jiang Erlie
Published: September 2023

Autologous hematopoietic stem cell transplantation (auto‐HSCT), matched sibling donor HSCT (MSD‐HSCT), and alternative donor HSCT (AD‐HSCT) are viable post‐remission treatment options for acute myeloid leukemia (AML). A total of 283 de novo favorable‐ and intermediate‐risk AML patients, based on the ELN 2022 criteria, in first complete remission were initially included for propensity score matching. Following the matching process, 126 patients were selected for further analysis, with 42 patients in each of the auto‐HSCT, MSD‐HSCT, and AD‐HSCT groups. Among the AD‐HSCT group, 38 of 42 (90.5%) patients received haploidentical HSCT. In patients with persistent undetectable measurable residual disease (uMRD) before transplant (n = 83), overall survival (OS) was similar across the groups. However, auto‐HSCT showed a trend of increased disease‐free survival (DFS) compared to AD‐HSCT (HR 2.85, P = 0.09), resulting in a 3‐year DFS and OS of 79.1% and 82.8%, respectively. In the non‐persistent uMRD group (n = 38), auto‐HSCT exhibited a tendency to increase the risk of relapse, particularly when compared to AD‐HSCT (HR 0.24, P = 0.07), but this did not result in inferior OS. The monthly direct medical cost per patient within the first 2 years after HSCT was significantly lower in auto‐HSCT compared to MSD‐HSCT (P = 0.015) and AD‐HSCT (P < 0.001). Our results provide evidence for the use of auto‐HSCT as a viable therapeutic option for favorable‐ and intermediate‐risk de novo AML patients in first complete remission with persistent uMRD. Additionally, our findings demonstrated a notable cost advantage associated with auto‐HSCT compared to MSD‐HSCT and AD‐HSCT.
A case study on using an intrauterine foley catheter to reduce postpartum bleeding in a patient with hemophilia
Authors: Yared Georges , Tachdjian Annie , El Kazwini Mohammad El Jawad , Azzi Joelle , El Hajjar Charlotte , Ghazal Kariman
Published: September 2023

Synopsis

Case of a pregnant patient suffering from severe hemophilia A who had effective uterine foley tamponade to treat postpartum hemorrhage.
Systems Engineering Management in Research and Development Valley of Death
Authors: DiMario Michael , Hodges Ann
Published: September 2023

A failure of a great many early research and development programs is the result of encountering the traditional valley of death that shadows early research and technology development. The elements that create the valley of death leads to research and technology development high risk and poor return on investment for a great many research and development organizations. This leads eventually to avoiding research and technology development all together because the organizations cannot viably manage the outcome of their early‐stage research and development (ESR&D) efforts. Unfortunately, there are few established frameworks and processes for enabling smooth transitions to avoid failure and manage risk across fundamental research, applied research, development, and productization. Many leaders, program managers, and scientists are unwilling to involve systems engineering because of the perception that systems engineering is heavily process oriented, adds unnecessary costs, and should be applied only to mature technologies. The value of systems engineering as applied to ESR&D is unclear to these key individuals. The unfortunate result is that systems engineering is not applied to ESR&D. This article discusses the potential of application of systems engineering to ESR&D to improve return on investment and decrease risk.
Systems Engineering in Technology Development
Authors: Sly Jaime , Crowne David
Published: September 2023

Technology development is the crucial first step in designing new products and systems. It is a unique phase of product development in that it incorporates both scientific exploration and reduction to an engineered result. Too often, systems thinking and systems engineering principles aren't applied at this stage, leading to technologies that solve the wrong problems, inability to progress to higher maturity levels, and unworkable implementation architectures. In practice, this means higher development costs, extended timelines, and failed technology development projects. This article presents a framework for and provides guidance on systems engineering activities that add value and improve outcomes if applied during early stages of product development.
The Pharmacology of Adenosine
Authors: Pelleg Amir , Porter R. Stephen
Published: September 2023

Adenosine is a purine nucleoside present in every cell of the human body. It is released into the extracellular space under physiologic and pathophysiologic conditions characterized by increased oxygen demand: supply ratio. Adenosine can exert a wide spectrum of effects in various organs and tissues. Exogenous adenosine has a wide spectrum of effects in experimental animal models as well as humans. The pharmacokinetics, pharmacodynamics, and the interaction of adenosine with other drugs are reviewed.
Evaluation of Bromfenac, Aspirin, and Ibuprofen in Postoperative Oral Surgery Pain
Authors: Forbes James A. , Edquist Irene A. , Smith Frederick G. , Schwartz Michael K. , Beaver William T.
Published: September 2023

Two hundred forty‐one outpatients with postoperative pain after the surgical removal of impacted third molars were randomly assigned, on a double‐blind basis, to receive a single oral dose of bromfenac 5, 10, or 25 mg, aspirin 650 mg, ibuprofen 400 mg, or placebo. Using a self‐rating record, subjects rated their pain and its relief for 8 hours after medicating. Estimates of summed pain intensity difference, peak pain intensity difference, total relief, peak relief, and hours of 50% relief were derived from these subjective reports. All active treatments were significantly superior to placebo, and the slope of the dose‐response curve for bromfenac was significant. Bromfenac 5 mg and aspirin 650 mg were equianalgesic; bromfenac 25 mg was slightly more efficacious than ibuprofen 400 mg. Bromfenac 25 mg and ibuprofen 400 mg were significantly superior to the other active treatments. Adverse effects were transient and consistent with the pharmacologic profiles of the medications evaluated.
Prolonged Nausea and Vomiting Associated with Buprenorphine
Authors: Fullerton Terence , Timm Edward G. , Kolski Gerald B. , Bertino Joseph S.
Published: September 2023

We conducted a trial to evaluate the histamine‐releasing characteristics of morphine, meperidine, and buprenorphine when administered intravenously to 20 healthy adults without pain. Substantially more nausea and vomiting occurred with buprenorphine than with the other compounds, and was more intense on ambulation. High‐affinity receptor binding may play a role in the long duration of nausea and vomiting after a single dose of this agent.
Normal and Abnormal Development of the Male Urogenital Tract
Authors: CUNHA GERALD R. , ALARID ELAINE T. , TURNER TIMOTHY , DONJACOUR ANNEMARIE A. , BOUTIN EUGENIE L. , FOSTER BARBARA A.
Published: September 2023

ABSTRACT: Androgen‐dependent male urogenital development occurs via mesenchymal‐epithelial interactions in which mesenchyme induces epithelial morphogenesis, regulates epithelial proliferation, and evokes expression of tissue‐specific secretory proteins. Mesenchymal‐epithelial interactions continue to be important into adulthood. For example, mesenchyme of the urogenital sinus (UGM) and seminal vesicle (SVM) induce dramatic morphologic and functional changes in various adult epithelia. Since adult epithelial cells are unquestionably responsive to mesenchymes that can elicit expression of alternative morphologic and functional phenotypes, established carcinomas might also be influenced by their connective tissue environment. In this regard, Dunning prostatic tumor has been induced by UGM or SVM to differentiate into tall columnar secretory epithelial cells. This change in cytodifferentiation is associated with a reduction in growth rate and loss of tumorigenesis. The role of soluble growth factors in the mechanism of mesenchymal‐epithelial interactions is discussed.
Sperm Surface Proteins After Capacitation
Authors: FUSI F. M. , LORENZETTI I. , VIGNALI M. , BRONSON R.A.
Published: September 2023

ABSTRACT: Several integrins recognize as ligands proteins containing the Arg‐Gly‐Asp (RGD) sequence, such as fibronectin, vitronectin, and laminin. It has been previously demonstrated that oligopeptides containing the RGD sequence competitively inhibit both the adhesion of hamster and human sperm to zona‐free hamster eggs and their subsequent penetration. In addition, the appearance of fibronectin on the surface of living human spermatozoa after capacitation has been demonstrated. In this work, it is shown that spermatozoa incubated overnight under capacitating conditions, but not fresh spermatozoa, also display the RGD‐containing proteins vitronectin and laminin. Whereas the expression of fibronectin does not appear to be localized to any specific region of the sperm surface, laminin is present solely on the sperm tail, and vitronectin was detected mostly as an equatorial band on the sperm head. The percent of capacitated spermatozoa within each ejaculate reacting with antivitronectin antibodies (51% to 94%) was similar to that observed with antifibronectin antibodies (72% to 100%) in a series of fertile donors, and in a series of infertile men (7% to 98% for vitronectin versus 5% to 100% for fibronectin). In contrast, the percent of spermatozoa displaying laminin was lower, ranging from 2% to 42% for fertile donors and from 5% to 34% for infertile donors, and was unrelated to the expression of fibronectin or vitronectin. The time of appearance of both fibronectin and vitronectin when spermatozoa were incubated under capacitating conditions varied for different sperm donors, suggesting a difference in the process of their expression between different men. The specificity of antivitronectin antibody binding to human spermatozoa was demonstrated by competitive inhibition with purified human vitronectin. That there was no immunologic reaction between the antivitronectin antibodies used and fibronectin was demonstrated both by the failure of free fibronectin to inhibit antivitronectin antibody binding to spermatozoa, and by Dot blot analysis. A partial cross‐reaction of the polyclonal antivitronectin antibody with fibronectin was shown by Western blot analysis, but this phenomenon was not present when the monoclonal antivitronectin antibody was used. In addition, both fibronectin and vitronectin could be extracted from capacitated spermatozoa solubilized in Chaps buffer, as shown by Dot blot and Western blot analysis. These observations suggest that vitronectin and fibronectin expressed on the surface of capacitated human spermatozoa could act as a ligand for specific receptors on the egg, and play a role in sperm—oolemmal adhesion.
Differential Regulation in the Release of Bioactive Versus Immunoactive Gonadotropins from Cultured Rat Pituitary Cells by Inhibin and Androgens
Authors: DAHL KRISTINE D. , CAMPEN CAROLYN A. , McGUINNESS DOROTHY M. , VALE WYLIE
Published: September 2023

ABSTRACT: Using in vitro bioassays and radioimmunoassays, the authors examined the interactions between purified 32kD ovine inhibin, testosterone, and dihydrotestosterone on basal and GnRH‐stimulated secretion of gonadotropins in primary rat pituitary cell cultures. This study demonstrates that inhibin and androgens: 1) differentially regulate gonadotropin levels, 2) cause changes in the amounts of bioactive and immunoactive FSH and LH released. In conclusion, differences in bio‐ and immuno‐FSH and LH secretion suggest that the endocrine milieu results in not only quantitative but qualitative changes in the secreted gonadotropin isoforms.
Dose‐Response Effects of Gonadotropin‐releasing Hormone on Plasma Concentrations of Gonadotropins and Testosterone in Fertile and Subfertile Stallions
Authors: ROSER JANET F. , HUGHES JOHN P.
Published: September 2023

ABSTRACT: Five fertile and five subfertile stallions were treated with a single intravenous injection of saline the first week followed by a single intravenous injection of varying doses of gonadotropin‐releasing hormone (5, 10, 25, 100, 500 μg) given in a randomized fashion over the next 5 weeks during the nonbreeding season. Blood samples were collected periodically before and after treatment for analysis of luteinizing hormone, follicle stimulating hormone, and testosterone content by radioimmunoassay. Before treatment, semen samples were collected every other day for 3 weeks for analysis of volume, concentration, motility, pH, and morphology. Basal plasma levels of luteinizing hormone were higher (P < 0.05) in the subfertile group, follicle stimulating hormone levels tended to be higher (P < 0.10) in the subfertile group, and testosterone levels were similar in the two groups. A significant linear‐log dose‐response relationship was observed for plasma luteinizing hormone (P < 0.05) and follicle stimulating hormone (P < 0.05) to exogenous gonadotropin‐releasing hormone in both the fertile and subfertile group. A linear‐log dose‐response relationship was also observed for plasma testosterone (P < 0.05) in the fertile group. The magnitude of the luteinizing hormone and follicle stimulating hormone response to gonadotropin‐releasing hormone across doses was similar in both groups of stallions. A significant testosterone response to gonadotropin‐releasing hormone in the subfertile group of stallions was not observed (P > 0.05). Mean testosterone concentrations after treatment in terms of net increase and percent of baseline were significantly lower (P < 0.05) in the subfertile group compared to the fertile group. Total viable sperm was lower (P < 0.05) in the subfertile group than in the fertile group of stallions. These results demonstrate that, in the nonbreeding season, the pituitary of subfertile stallions, like fertile stallions, has the capacity to respond to exogenous gonadotropin‐releasing hormone in a significant linear‐log dose‐response fashion. However, the capacity of Leydig cells to respond to increasing doses of gonadotropin releasing hormone (via endogenous luteinizing hormone) is significantly reduced in subfertile stallions compared to fertile stallions. The findings that subfertile stallions have high basal levels of gonadotropins, normal basal levels of testosterone, and yet a poor testosterone response to gonadotropin‐releasing hormone suggests that the endocrine dysfunction in stallions with idiopathic subfertility is associated with impaired Leydig/Sertoli cell function and/or alterations in the functional capacity of the hypothalamic‐pituitary axis.
Testicular Capillary Permeability: The Movement of Luteinizing Hormone from the Vascular to the Interstitial Compartment
Authors: TURNER T. T. , RHOADES C. P.
Published: September 2023

ABSTRACT: It has previously been shown in several species that pulses of luteinizing hormone (LH) in peripheral serum are followed within 10–20 minutes by pulses of testosterone. Whether or not LH pulses directly stimulate Leydig cells to produce the testosterone pulses would depend on the vascular permeability of LH within that physiologically relevant time. In the present experiments, the capillary permeability of the testicular microvasculature was characterized in adult rats, and the relative permeability to LH was determined. Adult male rats were prepared for in vivo micropuncture and testes were infused with 3H‐water, 14C‐urea, 14C‐polyethylene glycol (PEG), and 3H‐dextran directly into the testicular surface artery. Testicular interstitial fluid (TIF) and testicular venous plasma were collected at 5 minutes, 10 minutes, and 15 minutes after initiation of isotope infusion. Data were recorded as isotope concentration in TIF as a proportion of the isotope concentration in testicular venous plasma collected at that same time period. 3H‐water movement into the TIF from blood was rapid reaching 50% of serum values within 15 minutes. 14C‐PEG and 3H‐dextran were largely excluded from the TIF, typically not exceeding 5–10% of serum concentrations. In subsequent experiments, 125I‐LH was infused using the same protocol. 128I‐LH concentrations in TIF were 3.6 ± 2.0% of plasma concentrations 10 minutes after initiation of infusion. Preceding the 125I‐LH infusion experiments with 5‐day hypophysectomy or with LH pulses delivered either 10 minutes or 4 hours prior to the initiation of infusion did not alter the capillary permeability of 125I‐LH. These data demonstrate the restricted availability of LH to the TIF. This implies that Leydig cells are not exposed to LH pulses through the TIF and raises the question whether LH pulses directly stimulate testosterone pulses.
Sperm Immobilizing Activity of a Synthetic Bioactive Peptide 20–44 of 37‐kDa Cationic Antimicrobial Protein (CAP37) of Human Neutrophils
Authors: D'CRUZ OSMOND J. , PEREIRA H. ANNE , HAAS GILBERT G.
Published: September 2023

ABSTRACT: We have previously reported that human sperm coincubated with human peripheral blood neutrophils in the presence of complement (C)‐fixing antisperm antibody (ASA)‐positive sera are rapidly internalized and degraded within the neutrophil phagolyso‐some. However, the mechanism by which motile sperm are processed within the phagolysosome is unknown. Various spermicidal/antimicrobial proteins contained in azurophilic granules that can be secreted into the phagolysosome may play a role in sperm disposal. In this study, we examined the expression of a 37‐kDa cationic antimicrobial protein (CAP37) during sperm phagocytosis and the effect of its synthetic bioactive fragment, Peptide 20–44 (P20‐44), on sperm motility, acrosomal integrity, and mitochondrial functionality. CAP37 expression by neutrophils undergoing ASA‐ and C‐dependent sperm phagocytosis was increased as measured by flow cytometry. Exposure of motile sperm to a cationic P20‐44, the bioactive antimicrobial fragment of CAP37, resulted in the loss of sperm motility without disruption of the acrosomal membrane. The sperm immobilizing activity (SIA) of P20‐44 was modulated by the length of incubation, the concentration of the peptide, and the pH of the assay medium. SIA induced by P20‐44 was partially reversible and was unaffected by the presence of anionic heparin or seminal plasma. Similar to the antimicrobial activity of P20‐44, the SIA was also dependent on the presence of a disulfide bond between cysteine residues at positions 26 and 42 and was inhibited by Lipid A. However, the mechanism of action of P20‐44 on sperm is not totally dependent on the molecule's cationicity, because five other cationic antimicrobial peptides had no detectable effect on sperm viability. Thus, the mechanism of action of P20‐44 on human sperm is different from its cationic antibactericidal effect. These findings established that motile human sperm are sensitive to CAP37 or its synthetic bioactive peptide and suggested that this protein could play a role in neutrophil‐mediated immune destruction of sperm in the female genital tract. P20‐44 of CAP37 may be useful in investigating the regulation of human sperm motility and to construct “hybrid peptides” with enhanced potency as a component of vaginal contraceptive that could doubly be effective by killing infectious agents and inhibiting sperm transport.
Effects of Lipoprotein, Equine Luteinizing Hormone, Equine Follicle‐Stimulating Hormone, and Equine Prolactin on Equine Testicular Steroidogenesis In Vitro
Authors: Eisenhauer Karen M. , Roser Janet F.
Published: September 2023

ABSTRACT: A stallion testicular cell incubation system was developed and used to investigate the regulation of steroidogenesis in stallion testes. Cells isolated from testes of 2‐ to 4‐year‐old stallions (n = 6) were cultured for 12 hours in a defined medium with and without varying doses of lipoprotein, equine luteinizing hormone (eLH), human chorionic gonadotropin (hCG), equine follicle‐stimulating hormone (eFSH), and/or equine prolactin (ePRL). Estrogen conjugate (EC), testosterone (T), and estradiol‐17β (E2) production were determined by RIA. Increasing doses of lipoprotein significantly (P < 0.001) increased basal, hCG‐ and eLH‐stimulated EC production, resulting in a maximal fourfold increase in each case. A maximal dose of lipoprotein (3 mg/ml) significantly (P < 0.001) increased basal T production threefold, whereas hCG‐ and eLH‐stimulated T production were increased 76‐ and 30‐fold, respectively. In the presence of 0.5 mg/ml of lipoprotein, increasing doses of eLH significantly (P < 0.001) stimulated EC, T, and E2 production. The increase in T production (5.6‐fold) at a physiological dose of eLH (5 ng/ml) was significantly (P < 0.05) greater than the increase in EC or E2 production (2.1‐ and 2.3‐fold, respectively). However, the total mass of EC produced was significantly greater (P < 0.05) than the total amount of T produced at both basal (15 ng vs. 148 pg) or hormonestimulated (48 ng vs. 2,427 pg at 5 ng/ml eLH) levels. hCG significantly (P < 0.001) stimulated EC and T production and was 82‐fold more active in stimulating EC production and 41‐fold more active in stimulating T production than was eLH. FSH had no significant effect on steroidogenesis either alone or in the presence of eLH, except at the highest dose tested (50 ng/ml), which was above the physiological level of circulating FSH (4–7 ng/ml) in the stallion. PRL (1–50 ng/ml) had no significant effect on steroidogenesis either alone or in the presence of eLH. These data suggest that in the postpubertal stallion, both estrogen and T production are regulated by LH, and this regulation appears to be dependent on the availability of lipoproteinderived cholesterol. Furthermore, the observation that testicular cells produced a larger mass of EC than T, but responded to eLH with a larger relative increase in T production, suggests that production of these two steroids may be independently regulated.
Anti‐Androgen Effects of the Aromatase Inhibitor, Atamestane
Authors: SHAO TSANG C. , MARCELLI MARCO , KONG ANN , CUNNINGHAM GLENN R.
Published: September 2023

ABSTRACT: Prostatic hyperplasia can be induced in both intact and castrated dogs and in intact cynomolgus monkeys by the administration of androgenic steroids. Estrogenic steroids potentiate this effect in dogs. These changes also can be induced by andros‐tenedione, which increases androgen and estrogen levels. Atamestane (ATA; 1‐methyl‐3,17‐dione‐androsta‐1,4‐diene), a potent aromatase inhibitor, inhibits some of the androstendione‐induced effects; however, the nonsteroidal aromatase inhibitor, CGS‐16949A, has been reported to decrease serum estradiol levels in adult rats but to have no effect on androgen‐dependent organ weights. To examine the mechanisms by which ATA affects the rat prostate, in vivo and in vitro studies were conducted using adult rat ventral prostate (VP). Intact Sprague‐Dawtey rats were injected daily for 14 days with sesame seed oil, ATA (70 mg/kg/day), finasteride (FIN; 5 mg/kg/day), a 5α‐reductase inhibitor, or the combination of FIN plus ATA. A fifth group was castrated (CASTR) on day 1. The mean ± standard error VP weight of the controls was 350 ± 19 mg. It was reduced 17% (P < 0.05) by ATA, 29% (P < 0.001) by FIN, 48% (P < 0.001) by FIN plus ATA, and 86% (P < 0.001) by CASTR. The DNA/VP was reduced 22% (not significant) by ATA, 18% by FIN (not significant), 35% (P < 0.01) by FIN plus ATA, and 60% (P < 0.001) by CASTR. More significant changes were observed in RNA and protein. The mRNA for prostatein C3 was reduced by each of the treatments, but only CASTR increased the mRNA for TRPM‐2, a marker of apoptosis. In VP explant cultures the effect of DHT on maintaining prostatein C3 mRNA was inhibited by ATA, and ATA was observed to compete with tritiated dihydrotestosterone ([3H]DHT) for binding to the cytosolic androgen receptor (AR) of the rat VP with an approximate k1, of 3.5 × 10−4 M. To further investigate the anti‐androgenic properties of ATA, CV‐1 cells were transfected with expression plasmids encoding the human AR, cytomegalovirus‐β‐galactosidase, and the reporter plasmid, MMTV‐CAT. DHT‐activated expression of chloramphenicol acetyl transferase activity was reduced from 100% to 57% by 1 μM ATA and to 31% by 10 μM ATA. We conclude that ATA causes involution of the rat VP and that this effect is potentiated by the addition of FIN. It is likely that at least part of the effects of ATA on the rat VP are caused by anti‐androgenic properties of ATA.
Human Chorionic Gonadotropin But Not the Calcitonin Gene‐Related Peptide Induces Postnatal Testicular Descent in Mice
Authors: HOULE ANNE‐MARIE , GAGNÉ DONALD
Published: September 2023

ABSTRACT: The androgen‐regulated paracrine factor, calcitonin gene‐related peptide (CGRP), has been proposed as a possible mediator of testicular descent. This peptide has been found to increase rhythmic contractions of gubernaculae and is known to be released by the genitofemoral nerve. We have investigated the ability of CGRP to induce premature testicular descent. CGRP was administered alone, or in combination with human chorionic gonadotropin (hCG) to C57BLV/6 male mice postnatally. The extent of testicular descent at 18 days postpartum was then ascertained. The potential relationship between testicular weight and descent was also examined. Our results show that testes of mice treated with either hCG alone, or in combination with 500 ng CGRP, were at a significantly lower position than those of controls by 16% and 17%, respectively. In contrast, mice treated with 500 ng of CGRP alone had testes at a higher position when compared to those of controls, by 19%. In mice treated with 50 ng of CGRP alone or in combination with hCG, testes were at a position similar to those in controls. Furthermore, testicular descent was analyzed in relation to testicular weight, and we found that significantly smaller testes per gram of body weight than those of controls were at a significantly lower position compared to those of controls. Our data demonstrate that CGRP had no effect on postnatal testicular descent and that there is no relationship between postnatal descent and testicular weight.
Acute Effects of Spinal Cord Injury on the Pituitary‐Testicular Hormone Axis and Sertoli Cell Functions: A Time Course Study
Authors: HUANG H. F. S. , LINSENMEYER T. A. , LI M. T. , GIGLIO W. , ANESETTI R. , VON HAGEN J. , OTTENWELLER J. E. , SERENAS C. , POGACH L.
Published: September 2023

ABSTRACT: The present study investigated the time course of the onset of the abnormalities in spermatogenesis following spinal cord injury, and their relationship to changes in the pituitary testicular hormonal axis and Sertoli cell function.

These results suggest that spinal cord injury will result in a temporary, but profound, effect on the pituitary‐testicular hormone axis. These changes may impair certain aspects of Sertoli cell function that could render these cells incapable of supporting normal spermatogenesis. However, the seventy of spermatogenic lesions and the disparate responses of the two major Sertoli cell proteins make it unlikely that hormone deficiency is the only mechanism responsible for the impaired spermatogenesis following spinal cord injury.

Spinal cord injury (SCI) was induced in adult male rats by surgical transection of the spinal cord at the level of T9 and L1 vertebrae. Animals were killed 3, 7, and 14 days after the operation. As early as 3 days following SCI, abnormalities in spermatogenesis, including delayed spermiation and vacuolization of the nucleus of spermatids, were noted in both the T9 and L1 animals. By 14 days, other lesions, including phagocytosis of mature spermatids, incomplete cellular associations, and total regression of seminiferous epithelium, became apparent. Concurrently a transient but significant (P < 0.05) suppression of serum follicle‐stimulating hormone (FSH) occurred in the T9 animals, and a suppression of serum luteinizing hormone (LH) occurred in both the T9 and the L1 animals 3 days after the surgery. This was accompanied by a suppression of testicular and serum testosterone levels (P < 0.05, P < 0.01, respectively). Most of the hormonal parameters had recovered and were not different from those of sham‐operated animals by 14 days (P > 0.10). Northern blot analysis of testicular poty(A)+ RNA revealed a transient but significant reduction in the steady‐state level of the 2.7‐kilobase (kb) Sertoli cell transferrin mRNA transcript in both the T9 and the L1 animals 3 days after the operation (P < 0.05). On the other hand, the 1.7‐kb androgen binding protein (ABP) mRNA remained unaffected during the 2‐week study period. The steady‐state level of mRNA transcripts for spermatogenic cell‐specific hemiferrin and spermatid specific transition protein 2 and protamine 1 also remained unchanged.