Number Of Nuclei Research Articles

Neuromuscular Junction Remodeling: the Role of Sub-Synaptic Nuclei, Terminal Schwann Cells, and Trophic Signaling Following Neuromusculoskeletal Injuries

Peripheral nerve crush injury is a well-established model of neuromuscular junction (NMJ) denervation and subsequent re-innervation. Functionally, the muscle tissue follows a similar pattern as neural recovery, with immediate loss of force production that steadily improves in parallel with rates of re-innervation. On the other hand, traumatic injury to the muscle tissue itself, specifically volumetric muscle loss (VML), results in an irrecoverable loss of muscle function. Recent work has indicated significant impairments to the NMJ following VML that appear chronic in nature, alongside functional recovery. Thus, the goal of this study was to compare the effects of nerve and muscle injury on NMJ remodeling, with the hypothesis that VML will result in chronic alterations to the NMJ, including a higher degree of cellular localization to the NMJ. Even numbers of adult male and female mice were used with three experimental groups: injury naive, nerve crush, and VML-injury; and three terminal timepoints: 3-, 48-, and 112-days post injury. Data were analyzed by three-way ANOVA with Tukey’s HSD post-hoc. Confirming the assumed recoverability of the two injury models, we found in vivo maximal torque was fully restored following nerve crush injury (Tukey’s HSD post hoc p=0.730), but remained at a significant deficit following VML (~41% lower than injury naïve; Tukey’s HSD post hoc p<0.001). Compared to nerve crush and injury naïve, we found VML results in aberrantly high trophic signaling and numbers of supporting cells. Protein expression of neuregulin-1 and connective tissue growth factor were both highest in the VML group (~1.2-fold and 12-fold increase compared to injury naïve, respectively; Main effect of group, p<0.001). While nerve crush injury elicited a transient increase in terminal Schwann cell numbers (~38% higher than injury naïve at 48dpi; Tukey’s HSD post hoc p<0.001), VML resulted in a chronic increase (~53% and 27% higher than injury naïve at 48 and 112dpi, respectively; Tukey’s HSD post hoc p<0.001). Moreover, nerve crush injury did not alter the number of sub-synaptic nuclei per NMJ, while VML resulted in significant increases at both 48- and 112-days post injury (~27% and 24% higher than injury naïve, respectively; Tukey’s HSD post hoc p=0.002). In some cases, sex differences were detected, including higher rates of innervation in females than males (Main effect of sex p=0.003), particularly following VML-injury (Tukey’s HSD post hoc p=0.004). The findings herein bear a striking resemblance to NMJs found in dystrophic muscle, which are thought to be the result of continuous cycles of muscle fiber degeneration and regeneration. Thus, the NMJ changes observed following VML may be indicative of a larger issue, such as chronic muscle fiber remodeling and pervasive fibrotic accumulation. R01-AR078903 (JAC & SMG); K02-AG081488 (SMG). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Glucose-Induced Cellular Morphological Changes Across Mammalian Species

All organisms encounter environmental fluctuations and must contend with these changes to maintain homeostasis. Some mammals tolerate a wide range of intracellular conditions while others do not. Altered glucose levels are an example of a physiological challenge that can be encountered by cells. We studied responses of dermal fibroblasts obtained from skin biopsies to altered glucose treatments in culture using a comparative approach. Specifically, we investigated responses of mammals known to tolerate a range of blood glucose levels (fruit-eating geladas and Egyptian rousettes) as well as a hibernator (ground squirrel), which exhibits a marked winter decrease in glucose metabolism. As a comparison, we investigated species that maintain fairly stable blood glucose (human and rat). Fibroblasts were cultured at baseline (8mM glucose), then subjected to hypoglycemic (2.5mM) and hyperglycemic (30mM) treatment over 24h. We assayed glycolytic rate in human and rat fibroblasts using a Seahorse XFp analyzer, and found no significance between oxygen consumption or glycolysis across glucose treatments (all p>0.05). To investigate underlying cell phenotypes, we used Cell Painting, employing fluorescent stains to mark organelles. Hoechst 34580 stained DNA, to quantify number and size of nuclei, offering insights into proliferation. MitoTracker Deep Red visualized mitochondria, providing information about energy generation. Alexa Fluor 488 Concanavalin A conjugate marked endoplasmic reticulum. F-actin was stained with Alexa Fluor 555 Phalloidin conjugate, detecting cytoskeletal organization and overall cell structure. Images were analyzed with CellProfiler software, which extracts ~1400 morphological cell features, including area, compactness, fluorescence intensity, and cell connectivity to quantify subtle changes in phenotype. Each extracted feature will be compared across treatments and within a comparative context. We predict that fibroblasts exposed to hyperglycemia exhibit mitochondrial fragmentation and redistribution (MitoTracker) and increased production of reactive oxygen species (assessed with MitoSOX), which is linked to the opening of mitochondrial permeability transition pores. Cell Profiler analysis will identify structural changes that could indicate negative outcomes, such as mitophagy. Hyperglycemia may also induce endoplasmic stress, increasing lipid droplets and altering shape and size of the endoplasmic reticulum. In contrast, hypoglycemia will cause mitochondrial degradation. In both hyper- and hypoglycemia, proliferation rates are predicted to decrease, resulting in fewer nuclei and reduced cell connectivity. Phenotypic differences across species, evaluated in the context of their organismal phenotype, will help explain the mechanisms of cell function in mammals under environmental stress. Funding by NSF #2022046. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

In-situ observations of cloud microphysics over Arabian Sea during dust transport events

The unique in situ measurements of clouds and precipitation within the shallow and deep cumulus over the north-eastern Arabian Sea region during the Indian monsoon are illustrated in this study with a focus on droplet spectral parameters. The observational period showed a significant incursion of Arabian dust and the presence of giant cloud condensation nuclei (GCCN), modifying the cloud and precipitation spectral properties. Warm rain microphysics supported the mixed-phase development in these clouds and exhibited hydrometeors of snow, graupel and large aggregates as part of ice processes. Cloud base droplet number concentration is about 142 ± 79 cm−3 which is one third of the cloud condensation nuclei (CCN) number concentration at 0.2% supersaturation. A rapid broadening of droplet size distribution (DSD) near to the cloud base was noted in contrast to polluted continental clouds. Relationship between the relative dispersion ( ε; the ratio of DSD spectral width ( σ ) to mean radius ( rm )) and liquid water adiabatic fraction (AF) indicates that the entrainment effect has increased relative dispersion significantly (2–3 times larger) in these clouds. Effective radius ( reff ) is found to be proportional to mean volume radius ( rv ) with a proportionality constant ( β ) that varies between 1.0–1.6, depending on the spectral dispersion parameter. Drop size distributions for the small cloud droplets with size range 2–50 μ m and the large drizzle drops (or ice hydrometeors) with size range 100–6400 μ m are parameterized using the gamma function distributions useful for large-scale cloud models.

Reactions of Citrullus amarus and Cucumis metuliferus to Meloidogyne chitwoodi, Meloidogyne enterolobii and Meloidogyne luci

Meloidogyne chitwoodi, M. enterolobii, and M. luci are present in some EU countries, with restricted distributions, and plant resistance can be used to manage these nematodes. Two pot experiments were conducted under controlled conditions for 56 d to assess the host suitability of two potential rootstocks, Cucumis metuliferus BGV11135 and Citrullus amarus BGV5167, to one isolate of each nematode. The susceptible cucumber (Cucumis sativus) ‘Dasher II’, watermelon (Citrullus lanatus) ‘Sugar Baby’ and tomato (Solanum lycopersicum) ‘Coração-de-Boi’ were included for comparisons. A histopathological study using confocal-laser microscopy was also conducted 15 d after nematode inoculations. In the pot test, the rootstocks showed lower numbers of galls, egg masses, and eggs per plant than their susceptible ones. Reproduction indices of the rootstocks varied from immune to moderately resistant, depending on the isolate-rootstock combination. In the histopathological study, M. enterolobii and M. luci induced similar numbers of giant cells (GC) per feeding site in all germplasms. However, GC volumes and numbers of nuclei in rootstocks were lower than in the susceptible germplasms. GCs induced by M. chitwoodi were only detected in susceptible cucumber. These results emphasize the potential of C. metuliferus and C. amarus as effective, eco-friendly strategies for managing root-knot nematodes, and show the complex these host-pathogen interactions.

Supersaturation and Critical Size of Cloud Condensation Nuclei in Marine Stratus Clouds

AbstractObservations of marine stratus clouds in clean air off the Californian coast reveal a functional relationship between the number of cloud condensation nuclei (CCN) and supersaturation. Satellite‐derived liquid droplet density estimates the number density of CCN. Combining the estimated supersaturation using Köhler theory, global maps of supersaturation and the critical activation size of CCN are estimated. Here, we show that high supersaturation >0.5% persists over the oceans with a critical CCN size of 25–30 nm, which is smaller than the conventional wisdom of 60 nm. Independent support for such high supersaturation in the marine cloud is obtained from CCN measurements provided by the “Atmospheric Tomography Mission.” Higher supersaturation implies smaller activation size for CCN making cloud formation more sensitive to changes in aerosol nucleation.

Synthesis of a 50-electron triangular ruthenium cluster containing a μ3-methylidyne ligand via the fragmentation of the Ru2 skeleton

A chloride salt of cationic triruthenium complex containing a μ3-methylidyne ligand, [{Cp*Ru(μ-Cl)}3(μ3CH)]+ (4; Cp* = η5-C5Me5)), was synthesized by the reaction of diruthenium tetrahydrido complex [Cp*Ru(μ-H)4RuCp*] (1) with chloroform in 91% yield. Although 4 contains a 50-electron configuration, an X-ray diffraction study of a tetraphenylborate salt of 4 demonstrated that 4 has a closed-triangular triruthenium skeleton with a Ru−Ru distance of ca. 2.87 Å, which is considerably longer than the Cl-bridged Ru−Ru distance in the related 48-electron μ3-methylidyne complex, [(Cp*Ru)3(μ3CH)(μ-Cl)2(μ-H)]+ (5; 2.757(1) Å). Complex 4 was also obtained by the reaction of triruthenium pentahydrido complex [{Cp*Ru(μ-H)}3(μ3H)2] (2) with CHCl3, and crossover experiments using 2 and [{CpEtRu(μ-H)}3(μ3H)2] (2-Et3; CpEt = η5-C5EtMe4) demonstrated that the cluster skeleton of 2 was broken during the reaction. These results are contrasted with the exclusive formation of dinuclear μ-chloromethylidyne complex, [(Cp*RuCl)2(μ-CCl)(μ-Cl)] (3), by the reaction of 1 with CCl4, and the number of nuclei of the product is suggested to be determined by the substituent at the methylidyne carbon. Although a triruthenium complex was not formed by the reaction of 3 with [Cp*RuCl]4, a heterobimetallic trinuclear μ3-methylidyne complex, [(Cp*Ru)2(Cp*Ir)(μ3CH)(μ-Cl)(μ-H)2] (9) was obtained by the reaction of 3 with [Cp*IrH4] along with substitution of the chloromethylidyne ligand by a hydride.

Physiological DNA damage promotes functional endoreplication of mammary gland alveolar cells during lactation

Lactation insufficiency affects many women worldwide. During lactation, a large portion of mammary gland alveolar cells become polyploid, but how these cells balance the hyperproliferation occurring during normal alveologenesis with terminal differentiation required for lactation is unknown. Here, we show that DNA damage accumulates due to replication stress during pregnancy, activating the DNA damage response. Modulation of DNA damage levels in vivo by intraductal injections of nucleosides or DNA damaging agents reveals that the degree of DNA damage accumulated during pregnancy governs endoreplication and milk production. We identify a mechanism involving early mitotic arrest through CDK1 inactivation, resulting in a heterogeneous alveolar population with regards to ploidy and nuclei number. The inactivation of CDK1 is mediated by the DNA damage response kinase WEE1 with homozygous loss of Wee1 resulting in decreased endoreplication, alveologenesis and milk production. Thus, we propose that the DNA damage response to replication stress couples proliferation and endoreplication during mammary gland alveologenesis. Our study sheds light on mechanisms governing lactogenesis and identifies non-hormonal means for increasing milk production.

Possible retinotoxicity of long-term vardenafil treatment

Phosphodiesterase (PDE) inhibitors – such as vardenafil – are used primarily for treating erectile dysfunction via increasing cyclic guanosine monophosphate (cGMP) levels. Recent studies have also demonstrated their significant cardioprotective effects in several diseases, including diabetes, upon long-term, continuous application. However, PDE inhibitors are not specific for PDE5 and also inhibit the retinal isoform. A sustained rise in cGMP in photoreceptors is known to be toxic; therefore, we hypothesized that long-term vardenafil treatment might result in retinotoxicity. The hypothesis was tested in a clinically relevant animal model of type 2 diabetes mellitus. Histological experiments were performed on lean and diabetic Zucker Diabetic Fatty rats. Half of the animals were treated with vardenafil for six months, and the retinal effects were evaluated. Vardenafil treatment alleviated rod outer segment degeneration but decreased rod numbers in some positions and induced changes in the interphotoreceptor matrix, even in control animals. Vardenafil treatment decreased total retinal thickness in the control and diabetic groups and reduced the number of nuclei in the outer nuclear layer. Müller cell activation was detectable even in the vardenafil-treated control animals, and vardenafil did not improve gliosis in the diabetic group. Vardenafil-treated animals showed complex retinal alterations with improvements in some parameters while deterioration in others. Our results point towards the retinotoxicity of vardenafil, even without diabetes, which raises doubts about the retinal safety of long-term continuous vardenafil administration. This effect needs to be considered when approving PDE inhibitors for alternative indications.

Light-Regulated Nucleation for Growing Highly Uniform Single-Crystalline Microrods.

We report a light-irradiation method to control the synchronous nucleation of a donor-acceptor (D-A) fluorophore for growing highly uniform single-crystalline microrods, which is in sharp contrast to the prevailing methods of restricting spontaneous nucleation and additionally adding seeds. The D-A fluorophore was observed to undergo photoinduced electron transfer to CrCl3, leading to the generation of HCl and the subsequent protonation of the D-A fluorophore. By intensifying photoirradiation or prolonging its duration, the concentration of protonated D-A fluorophores can be rapidly increased to a high supersaturation level. This results in the formation of a controlled number of nuclei in a synchronous manner, which in turn kickstart the epitaxial growth of protonated D-A fluorophores towards uniform single-crystalline microrods of controlled sizes. The light-regulated synchronous nucleation and uniform growth of microrods are a unique phenomenon that can only be achieved by specific Lewis acids, making it a novel probing method for sensitively detecting strong Lewis acids such as chromium chloride.

Automatic Detection of Nuclear Spins at Arbitrary Magnetic Fields via Signal-to-Image AI Model.

Quantum sensors leverage matter's quantum properties to enable measurements with unprecedented spatial and spectral resolution. Among these sensors, those utilizing nitrogen-vacancy (NV) centers in diamond offer the distinct advantage of operating at room temperature. Nevertheless, signals received from NV centers are often complex, making interpretation challenging. This is especially relevant in low magnetic field scenarios, where standard approximations for modeling the system fail. Additionally, NV signals feature a prominent noise component. In this Letter, we present a signal-to-image deep learning model capable of automatically inferring the number of nuclear spins surrounding a NV sensor and the hyperfine couplings between the sensor and the nuclear spins. Our model is trained to operate effectively across various magnetic field scenarios, requires no prior knowledge of the involved nuclei, and is designed to handle noisy signals, leading to fast characterization of nuclear environments in real experimental conditions. With detailed numerical simulations, we test the performance of our model in scenarios involving varying numbers of nuclei, achieving an average error of less than 2kHz in the estimated hyperfine constants.

Widespread cortical and subcortical gray matter loss and an increase of globus pallidus volume in treatment-resistant schizophrenia

Introduction It is still being discussed whether treatment-resistant schizophrenia (TRS) is a biological subtype which differs from non-treatment-resistant schizophrenia or is it a more severe condition that affects brain worse than non-treatment-resistant schizophrenia. However, there are few and heterogeneous studies and the etiology of TRS remains quite unclear.ObjectivesThis study aimed to explore cortical and subcortical morphometric characteristics in TRS patients and its associations with the clinical features. The pilot stage comprises the comparison to the mentally healthy subjects.Methods 21 right-handed male patients (mean age 28.99 ± 8.08 years) fulfilling TRS criteria and 21 matched healthy controls (mean age 29.35 ± 7.41 years) underwent T1-weighted structural MRI at 3T Philips scanner and clinical examination. Images were processed using FreeSurfer 7.1.1. Cortical thickness and area, volumes of subcortical structures and separately volumes of the amygdala nuclei and hippocampal subregions were compared between groups. The morphometry data, PANSS (Positive and Negative Syndrome Scale), CDSS (Calgary Depression Scale for Schizophrenia) and daily chlorpromazine equivalent doses of antipsychotics were included in correlational analysis. Results were considered significant if they retained significance after correction for multiple comparisons.Results Compared to healthy controls, TRS patients showed decreased gray matter thickness in frontal, temporal, parietal, occipital, cingulate and insular regions (Figure 1). The temporal lobe showed the most prominent thinning of the cortex. The volumes of the amygdala, hippocampus (Figure 2) and nucleus accumbens, a number of amygdala nuclei and hippocampal subregions bilaterally were also decreased in TRS patients. The volume of the right globus pallidus, on the contrary, was increased (Figure 2). No correlations between altered cortical thickness, PANSS (positive, negative, general psychopathology scales and total score), CDSS and chlorpromazine equivalent doses of antipsychotics were found.Image:Image 2:Conclusions The widespread gray matter cortical and subcortical loss in TRS finds confirmation in the literature. The increased globus pallidus volume is an unexpected and intriguing result. Other studies demonstrated conflicting results on that point. Some studies reported possible therapy influence, others suggested possible associations with symptoms. We did not find any correlations with psychometric or therapy characteristics. It is possible that there are non-linear relationships or relationships that exist only at a certain stage of the disease. As for therapy, patients took individual medication, consisting of various antipsychotics and drugs from other pharmacological groups, and such heterogeneity could affect the results of the study. Further research is going to be carried out.Disclosure of InterestNone Declared

A Framework for Exploring Nuclear Physics Sensitivity in Numerical Simulations

We describe the AMReX-Astrophysics framework for exploring the sensitivity of astrophysical simulations to the details of a nuclear reaction network, including the number of nuclei, choice of reaction rates, and approximations used. This is explored by modeling a simple detonation with the Castro simulation code. The entire simulation methodology is open-source and GPU-enabled.

Effect of drugs regulating acute immune responses on the liver in septic processes

Objective. To study the effect of drugs regulating acute immune responses on liver in septic processes. Materials and methods. The study was conducted on 39 male white rats weighing 250-400 g. The animals were initiated septic process development by intraperitoneal injection of Klebsiella pneumoniae culture suspension with simultaneous intravenous injection of polyvinylpyrrolidone (PVP) and gadolinium in the volume of 0.6 ml. On the 14th day the animals were removed from the experiment by decapitation under light ether anesthesia, blood and liver were taken for biochemical and histological studies. Results. When analyzing the morphometric parameters of liver preparations, an increase in the number of nuclei and a slight increase in the area of nuclei in three experimental groups was established by 1,2 times (p < 0,05) compared to the control group, which reflects the ongoing processes of hepatocyte regeneration due to possible mechanisms, namely hypertrophy nuclei and proliferation with both PVP and gadolinium in systemic inflammatory response and sepsis. Moreover, the use of PVP and gadolinium led to a decrease in the likelihood of perinuclear edema, protein degeneration and large droplet vacuolization (p < 0,05). When using gadolinium, the lumen diameter of the sinusoids was the largest and amounted to 4,47; 3,22-5,63 µm (p<0,05), and in septic shock it did not differ from the group where PVP was used (p > 0,05). Of the laboratory parameters of surviving individuals, the lowest ALaT level was noted in the gadolinium experimental group – 53,7; 51,8-55,1 U/L (p<0,05), while the lowest urea level was observed when using PVP (5,0; 4,99-5,15 mmol/l) (p < 0,05) as part of a systemic inflammatory response. Conclusion. Gadolinium and PVP have a positive effect on the detoxification function of liver. Moreover, the effect of PVP on the morphology and function of the liver differs at the stages of septic process.

Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)

Abstract. New particle formation (NPF) in the free troposphere (FT) is thought to be a significant source of particles over the oceans. The entrainment of particles initially formed in the marine FT is further suspected to be a major contributor to cloud condensation nuclei (CCN) number concentrations in the marine boundary layer (BL). Yet, little is known about the process and, more broadly, about the composition of the marine FT, which remains poorly explored due to access difficulties. Here we report measurements performed in April 2018 at the Maïdo Observatory with a nitrate-based chemical ionization atmospheric pressure interface time-of-flight mass spectrometer, which have allowed the first molecular-level characterization of the remote marine FT composition. A number of molecules and clusters were identified and classified into nine groups according to their chemical composition; among the identified species, the groups containing methanesulfonic acid (MSA) and C2 amines show signals that are on average significantly higher when the site is under conditions representative of the marine FT (compared to the BL). The correlation analysis revealed apparent connections between the signals of the identified compounds and several variables concurrently measured at the site (under FT conditions) or related to air mass history, suggesting that oxalic acid, malonic acid, and observed C2 amines could be of terrestrial origin, with, in addition, a possible marine source for oxalic acid and amines, while iodic acid, sulfur species, and maleic acid have a dominant marine origin. Identification of FT conditions at the site was based on the analysis of the standard deviation of the wind direction; this parameter, which can easily be derived from continuous measurements at the site, is shown in the first part of the study to be a relevant tracer when compared to predictions from the Meso-NH atmospheric model. Similar to other high-altitude sites, FT conditions are mainly encountered at night at Maïdo; therefore, the link to NPF could not be established, and further research is needed to assess the composition of precursors to nanoparticle formation in the marine FT.

Effect of electroacupuncture on behavior and hippocampal inflammatory factors in rats with chronic fatigue syndrome.

To observe the effect of electroacupuncture (EA) on the changes of behavior and hippocampal inflammatory factors in rats with chronic fatigue syndrome (CFS), so as to explore its possible mechanisms in the treatment of CFS. Twenty-seven SD rats were randomly divided into control, model and electroacupuncture (EA) groups (n=9 rats in each group). The CFS model was established by multi-factor compound stress stimulation method. Rats of the EA group received EA (10 Hz) at "Shenting" (GV24) penetrating "Baihui" (GV20), "Dazhui" (GV14) for 15 min, twice a day for 14 days. The general conditions, Morris water maze test, open field test, the exhausted running platform were conducted for determining the rats' locomotor and learning-memory activities. H.E. staining was used to observe the morphological structure of neurons in hippocampal CA1 region. The contents of interleukin (IL)-10, IL-17 and transforming growth factor (TGF) β1 in hippocampus and serum of rats were detected by ELISA, and the positive expressions of IL-10, IL-17 and TGF-β1 in hippocampal CA1 region were detected by immunofluorescence staining. Compared with the control group, the score of general condition was increased (P<0.05), the escape latency was prolonged (P<0.05), the number of crossing the original platform was decreased (P<0.05), the numbers of crossing the grid and entering the central area were increased (P<0.05), and the exhaustive treadmill time was shortened (P<0.05) in the model group. The contents of IL-10 in the hippocampus and serum were decreased (P<0.05), while IL-17 and TGF-β1 contents were increased (P<0.05). The immunofluorescence intensity of IL-10 in the hippocampus was decreased (P<0.05), while the intensity of IL-17 and TGF-β1 were increased (P<0.05). After treatment, compared with the model group, the score of general condition was decreased (P<0.05), the escape latency was shortened (P<0.05), the number of crossing the original platform was increased (P<0.05), the numbers of crossing the grid and entering the central area were decreased (P<0.05), and the exhaustive treadmill time was prolonged (P<0.05) in the EA group. The contents of IL-10 in the hippocampus and serum were increased (P<0.05), while IL-17 and TGF-β1 levels were decreased (P<0.05). The immunofluorescence intensity of IL-10 in the hippocampus was increased (P<0.05), while the intensity of IL-17 and TGF-β1 were decreased (P<0.05). H.E. staining showed that in the model group, the number of neurons in the hippocampus decreased, with disordered arrangement and loose structure, and a small numbers of neuronal nuclei were missing. The degree of tissue damage of the EA group was milder than that of the model group. EA can alleviate fatigue and spatial learning and memory impairment in CFS rats, which may be related to the regulation of peripheral and central inflammation.

Abstract 749: Randomized placebo-controlled phase II clinical trial on oral supplementation of sulforaphane for 12 months that reduced bronchial Ki-67 index in former smokers at high risk for lung cancer

Abstract Background: Epidemiological studies showed higher intake of cruciferous vegetables or their active compounds, isothiocyanates (ITCs), with lower risk of lung cancer. ITCs inhibited tobacco-carcinogen induced lung adenocarcinoma in animal models, along with reduced cellular proliferative marker Ki-67 and increased apoptotic markers Caspase-3 and TUNEL. However, human data lack. The aim of our study was to assess if oral intake of sulforaphane (SFN) for 12 months would stop/reverse the progression of bronchial histopathology, reduce Ki-67 index and/or increase Caspase-3 and TUNEL indices. Methods: A randomized clinical trial (NCT03232138) was conducted in former smokers with ≥ 30 pack-years and quitting smoking for 1-10 years in USA. Forty-three subjects were randomly assigned to the SFN (n = 21) or placebo group (n = 22) in 2018-2022. Each participant was instructed to take 4 Avmacol® or identical placebo capsules BID for 12 months. Each Avmacol® capsule contained 15 mg of glucoraphanin, which yielded a daily internal dose of 120 μmol SFN. Biopsies were collected from 6 predetermined bronchial sites at baseline and the end of treatment, respectively. The primary outcomes were the average changes of histopathology scores, Ki-67, Caspase-3 and TUNEL indices in post- vs. pre-treatment biopsies. Results: Thirty-seven participants completed the study. In the SFN group (n = 17) at baseline, 13 were men, all white, mean age 64.1 (SD 5.3) years, body mass index (BMI) 30.6 (6.1) kg/m2, years of smoking 39.5 (8.2), cigarettes per day (CPD) 23.8 (10.7), and years of quitting smoking 4.3 (2.9). The corresponding figures in the placebo group (n=20) were 9 men, 19 white, age 68.0 (3.2), BMI 28.6 (4.2), years of smoking 42.2 (4.5), CPD 25.5 (8.4), and years of quitting smoking 6.8 (3.2). The baseline medians of total Ki-67 positive nuclei were 22.3 nuclei/mm2 in the SFN group and 22.9/mm2 in the placebo group (p = 0.96). After treatment, the number of positive Ki-67 nuclei decreased by 5.3/mm2 (-24%) in the SFN group and increased by 18.0/mm2 (+79%) in the placebo group (p = 0.014) with adjustment for baseline Ki-67 and other covariates. The post- and pre-treatment difference was even greater in high-density (3+) positive Ki-67, with -46% decrease in the SFN group vs. +99% increase in the placebo group (p = 0.004). There was a dose-response effect of higher compliance with SFN intake on reducing Ki-67 index (ptrend = 0.01). SFN treatment had no impact on Caspase-3, TUNEL, or bronchial histopathology. No severe adverse event was observed in the SFN group. Conclusion: Daily intake of 120 μmol SFN for 12 months significantly reduced Ki-67 index in bronchial tissue. The findings support the potential chemopreventive effect of SFN against lung cancer development in high-risk former smokers (Grant # R01CA213123). Citation Format: Jian-Min Yuan, Thomas W. Kensler, Sanja Dacic, Douglas J. Harman, Renwei Wang, Paula Balogh, Lindsey Seigh, Yen T-H Pham, Jennifer Adams-Haduch, Shivendra Singh, James G. Herman, Avrum Spira, David O. Wilson. Randomized placebo-controlled phase II clinical trial on oral supplementation of sulforaphane for 12 months that reduced bronchial Ki-67 index in former smokers at high risk for lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 749.

Characterizing the Role of AosfgA and AofluG in Mycelial and Conidial Development in Arthrobotrys oligospora and Their Role in Secondary Metabolism.

Arthrobotrys oligospora, a widespread nematode-trapping fungus which can produce conidia for asexual reproduction and form trapping devices (traps) to catch nematodes. However, little is known about the sporulation mechanism of A. oligospora. This research characterized the functions and regulatory roles of the upstream spore-producing regulatory genes, AosfgA and AofluG, in A. oligospora. Our analysis showed that AosfgA and AofluG interacted with each other. Meanwhile, the AofluG gene was downregulated in the ΔAosfgA mutant strain, indicating that AosfgA positively regulates AofluG. Loss of the AosfgA and AofluG genes led to shorter hyphae and more septa, and the ΔAosfgA strain responded to heat and chemical stresses. Surprisingly, the number of nuclei was increased in the mycelia but reduced in the conidia of the ΔAosfgA and ΔAofluG mutants. In addition, after nematode induction, the number and volume of vacuoles were remarkably increased in the ΔAosfgA and ΔAofluG mutant strains. The abundance of metabolites was markedly decreased in the ΔAosfgA and ΔAofluG mutant strains. Collectively, the AosfgA and AofluG genes play critical roles in mycelial development, and they are also involved in vacuole assembly, the stress response, and secondary metabolism. Our study provides distinct insights into the regulatory mechanism of sporulation in nematode-trapping fungi.

Light‐Regulated Nucleation for Growing Highly Uniform Single‐Crystalline Microrods

We report a light‐irradiation method to control the synchronous nucleation of a donor‐acceptor (D‐A) fluorophore for growing highly uniform single‐crystalline microrods, which is in sharp contrast to the prevailing methods of inhibiting spontaneous nucleation and additionally adding seeds. The D‐A fluorophore was observed to undergo photoinduced electron transfer to CrCl3, leading to the generation of HCl and the subsequent protonation of the D‐A fluorophore. By intensifying photoirradiation or prolonging its duration, the concentration of protonated D‐A fluorophores can be rapidly increased to a high supersaturation level. This results in the formation of a controlled number of nuclei in a synchronous manner, which in turn kickstart the epitaxial growth of protonated D‐A fluorophores towards uniform single‐crystalline microrods of controlled sizes. The light‐regulated synchronous nucleation and uniform growth of microrods are a unique phenomenon that can only be achieved by specific Lewis acids, making it a novel probing method for sensitively detecting strong Lewis acids such as chromium chloride.

Novel role of thermomechanical grain boundary engineering in the microstructure evolution of austenitic stainless steel

The effect of special grain boundary development via the grain boundary engineering process (GBE) was explored in a bimodal microstructured 316L austenitic stainless steel with an average grain size of 1.92 μm. The GBE process was carried out by the rolling-annealing method via two routes of low and medium applied strain, followed by a short annealing period in a single-step and iterative manner. The grain boundary character distribution was obtained by Electron Backscatter Diffraction (EBSD) analysis, and the intergranular corrosion resistance and the tensile behavior of the samples were examined. Microstructural characterization showed that applying low strain repetitively increased the coincidence site lattice (CSL) and Σ3 boundaries percentage and created large twin-related domains (TRD). The reduced sensitization was attributed to a high proportion of CSLs and large-sized TRDs by applying a low-strain route. In the early stages of the low-strain route, the grain boundary character distribution showed a high number of primary twin nuclei in coarse grains and a continuous network of single twin nuclei in smaller grains, creating a high percentage of Σ3-grain boundaries. The low applied strain and the absence of the necessary driving force for the recrystallization and GBs migration led to the formation of twin nuclei, which would assist with the reduction of microstructure energy. A high percentage of Σ3 boundaries and an increase in the percentage of triple points consisting of low energy boundaries were found to be influential factors in increasing elongation.

Mitigating transcription noise via protein sharing in syncytial cells

Bursty transcription allows nuclei to concentrate the work of transcribing mRNA into short, intermittent intervals, potentially reducing transcriptional interference. However, bursts of mRNA production can increase noise in protein abundances. Here, we formulate models for gene expression in syncytia, or multinucleate cells, showing that protein abundance noise may be mitigated locally via spatial averaging of diffuse proteins. Our modeling shows a universal reduction in protein noise, which increases with the average number of nuclei per cell and persists even when the number of nuclei is itself a random variable. Experimental data comparing distributions of a cyclin mRNA that is conserved between brewer’s yeast and a closely related filamentous fungus Ashbya gossypii confirm that syncytism is permissive of greater levels of transcriptional noise. Our findings suggest that division of transcriptional labor between nuclei allows syncytia to sidestep tradeoffs between efficiency and precision of gene expression.