Anti-biofilm and antibacterial effect of Bacteriocin derived from Lactobacillus plantarum on the multidrug-resistant Acinetobacter baumannii.

This research examines the impact of bacteriocin derived from Lactobacillus plantarum PTCC 1745 on the biofilm formations of A. baumannii isolates. Bacteriocin derived from L. plantarum PTCC 1745 was obtained through ammonium sulfate precipitation, cation-exchange chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). Testing for bacteriocin susceptibility has been conducted using the broth dilution method. The anti-biofilm activity of bacteriocin was evaluated using a microtiter plate method. Quantitative real-time PCR assay evaluated bap gene expression in bacteriocin-treated cells. According to SDS-PAGE, bacteriocin from L. plantarum has a 25-kDa apparent molecular weight. The MICs of bacteriocin ranged from 30 to 120 µg/mL, while the MBCs varied between 60 to 120 µg/mL. Compared to the non-treated group, strains bacteriocin-treated isolates had 59% less ability to form biofilm. The mean relative expression of the bap gene among the MDR A. baumannii isolates decreased by 52% compared to the untreated control. This study demonstrated that bacteriocin derived from L. plantarum PTCC 1745 had antibacterial and antibiofilm activity against MDR A. baumannii isolates.

Biosystematic studies of genus Withania Pauquy in Egypt.

Withania (Solanaceae, Solanoideae) is a widespread genus. Comparative macro-, micro-morphological, anatomical, and molecular features of this genus in Egypt were examined using light and scanning electron microscopy to reassess the conflicted taxonomic relationships between the two studied species. The most significant morphological differences that have been found were: the shape of the lamina, apex, anther, and stigma, and the ratio of calyx tube/lobe; anatomical examination of taxonomic interest are as follows: number of vascular bundles, presence of ears and distribution of accessory vascular bundles in petiole and shape of spongy cells, and number of lower parenchyma in the midrib region of the leaf; trichomes of both species showed no significant differences; pollen, and seed characters are of taxonomic significance in differentiation and characterization between them. Protein profiling revealed that W. somnifera has only conserved proteins, while W. obtusifolia possessed both conserved and additional proteins in their SDS-PAGE banding patterns. Eleven starts codon-targeted (ScoT) primers were applied and produced 96 amplicons with an average of 70.83% polymorphism/primer. W. obtusifolia generated more polymorphic bands and maintained monomorphic ones. SDS-PAGE disclosed that both Withania species were 50% related. While Scot-Dendrogram revealed that both Withania species were poorly related. So, protein and molecular analyses showed considerable genetic variations between these two species.

Vaginal natural orifice transvaginal endoscopic surgery (vNOTES) for benign ovarian cysts is safe and feasible in same-day discharge: a retrospective cohort study.

BACKGROUND: Advances in minimally invasive surgery and the development of Enhanced Recovery After Surgery (ERAS) have favored the spread of day-surgery programs. Even though Vaginal natural orifice transvaginal endoscopic surgery (vNOTES) is accepted as an innovative treatment for benign ovarian cysts that is rapidly gaining recognition worldwide, the safety and feasibility of same-day surgery (SDS) have yet to be established. OBJECTIVE: This study aimed to evaluate the safety and feasibility of day surgery compared to inpatient surgery of patients undergoing vNOTES for benign ovarian cysts by determining perioperative outcomes. MATERIALS AND METHODS: The study consisted of 213 patients who underwent vNOTES for ovarian cystectomy at a single institution from January 2020 to November 2022. Based on the hospital stay, patients were classified into the same-day surgery group (SDSG) and the inpatient surgery group (ISG); after data processing and screening considering the balance of the two groups, SDSG has 83 samples(n = 83), and ISG has 113 samples(n = 113). The patient's demographic characteristics and follow-up data were collected during the perioperative period by doctors and nurses for medical tracking and analysis purposes and 1-month postoperatively by doctors in charge of their operation. Independent sample t-tests were performed to verify if there was any major difference between these two groups for continuous data like age, BMI, and cyst diameter, and Pearson's chi-squared tests were used to test whether there was a major difference between these two groups for categorical data like cyst count, abdominal surgery history and whether their cyst is bilateral ovarian cysts or not. The association between exhaust time and postoperative characteristics and the association between levels of pain and postoperative characteristics were further analyzed to unveil the confounding factors contributing to the same-day discharge method's quick recovery nature. RESULTS: Upon performing propensity score matching, 196 patients were finally enrolled in this study for the matched comparison, including 83(42.3%) patients in the SDSG and 113(57.7%) patients in the ISG. There was no statistical difference between the two groups in terms of duration of operation (85.0 ± 41.5 min vs. 80.5 ± 33.5 min), estimated blood loss (27.7 ± 28.0 ml vs. 36.3 ± 33.2 ml), preoperative hemoglobin levels (128.8 ± 13.2 g/L vs. 128.6 ± 14.0 g/L), postoperative hemoglobin difference at 24 h (16.5 ± 15.4 g/L vs. 19.3 ± 9.1 g/L), pelvic adhesions (42 (50.6%) vs. 47 (41.6%)), and postoperative complications (7(8.4%) vs. 4(3.5%)). The SDSG group showed less time of feeding/off-bed/exhaust/urination after surgery, shorter hospitalization duration, a lower postoperative 6-hour pain score, and a lower incidence of analgesic drug use. Multiple linear regression analysis showed that advancing the time of postoperative off-bed activity and feeding reduced the postoperative exhaust time by 0.34 (95% CI: 0.185-0.496, 0.34 h, p < 0.001) and 0.299(95% CI: 0.158-0.443, 0.229 h, p = 0.036) hours. In addition, Ordinal logistic regression revealed a correlation between pain scores and bilaterality of cyst, increasing about 25.98 times the risk of pain levels when ovarian cysts are bilateral (OR: 26.98, 95% CI: 1.071-679.859, P = 0.045). CONCLUSION: In this pilot study, same-day discharge after vaginal natural orifice transvaginal endoscopic ovarian cystectomy is safe and feasible. The vNOTES for ovarian cystectomy combined with the same-day discharge shorten the exhaust time and duration of hospitalization, reduce postoperative pain, and lower the use incidence of analgesic drugs.

Systematic review and meta-analysis of the effects of progestins on depression in post-menopausal women: An evaluation of randomized clinical studies that used validated questionnaires.

OBJECTIVE: Hormone therapy (HT) can relieve symptoms of menopause and treat chronic diseases. Its effectiveness in treating psychological symptoms is still debated. Several progestins can be used in HT, but their effects on mood, in particular depressive symptoms, is still unclear. This systematic review evaluates the evidence from randomized clinical trials with postmenopausal women on the effect of adjunctive progestins on symptoms of depression assessed by validated questionnaires. The primary aim was to evaluate scores on the Center for Epidemiologic Studies Depression Scale (CESD). The secondary aim was to assess scores on the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HAMD), and the Zung Self-Rating Depression Scale (SDS). METHODS: A systematic review and meta-analysis were conducted to identify the most reliable evidence of the effects of progestin on depression to inform decision-making. A PICO- and PRISMA-based framework was established to formulate explicit and reasoned recommendations. The pre-/post-treatment effect was evaluated using standardized mean change (SMC). RESULTS: We selected and analyzed 16 randomized clinical trials qualitatively and 12 studies quantitatively out of 9320 items identified. Most of the studies used medroxyprogesterone acetate as progestin. The results indicate that depressive symptoms do not increase with the addition of a progestin to estrogen HT. Depressive symptoms improved over time in the progestins-estrogen HT group, independent of progestin type (SMC CES-D -0.08 CI.95-0.10/-0.06, BDI -0.19 CI.95-0.32/-0.06, HAM-D -1.13 CI.95-1.47/-0.78, and SDS -0.11 CI.95-0.82/0.60). Yet similar effects were observed with estrogens alone and did not significantly differ from control groups on placebo. In one study, the addition of fluoxetine greatly increased the reduction of depressive symptoms observed with estrogen-progestin HT. CONCLUSIONS: In summary, in randomized clinical trials using validated questionnaires adjunctive progestin with estrogens did not increase depressive symptoms of postmenopausal women. Overall, depressive symptoms decreased with estrogen-progestin HT but also with estrogen alone. The decrease was not so pronounced to differ from controls on placebo. HT does not hamper the clinical efficacy of fluoxetine. The scarcity of randomized studies makes it difficult to determine the exact effect on depressive symptoms of different types of progestins. Project protocol registered in PROSPERO, registration number CRD42023454099.

Chemotherapy-induced neutropenia management in a patient with metastatic breast cancer and Shwachman-Diamond syndrome (SDS): a case report.

Background: Shwachman-Diamond syndrome (SDS) is a rare inherited bone marrow failure syndrome associated with cytopenia and the development of hematologic malignancies. Solid tumor occurrence is rare and, historically, these patients have had poor outcomes due to chemotherapy-induced myelosuppression and increased susceptibility to infections. We report the administration of cytotoxic systemic therapy with granulocyte colony-stimulating factor (G-CSF) in a patient with SDS and metastatic breast cancer. We describe the risk-benefit profile of utilizing G-CSF in managing this patient to improve her therapeutic outcome and review the prior literature. Case Description: A 41-year-old Caucasian female with SDS developed stage IV triple-positive [estrogen positive, progesterone positive, and human epidermal growth factor receptor 2 (HER2) positive] invasive ductal carcinoma of the left breast with liver metastases. She had lifelong thrombocytopenia with other hematologic parameters within normal limits, no tumor protein 53 (TP53) mutation, and no history of marrow dysplasia. Based on her underlying SDS, paclitaxel was favored over docetaxel due to the reduced risk of myelosuppression and weekly dosing schedule. Her regimen included weekly paclitaxel with trastuzumab and pertuzumab every 21 days. She experienced chemotherapy-induced neutropenia with an absolute neutrophil count of less than 1,500 leading to the utilization of G-CSF support. She received chemotherapy with twice-weekly G-CSF and did not experience severe infections. After nine cycles of therapy, she had no evidence of metastatic disease on imaging. The patient has an ongoing complete response at 18 months since treatment initiation. Conclusions: This case report describes the treatment of a patient with SDS and metastatic breast cancer with cytotoxic chemotherapy and G-CSF. G-CSF facilitated ongoing chemotherapy administration and reduced the risk of infection leading to an optimal therapeutic outcome. There should be careful consideration of early G-CSF use in patients with SDS to optimize continuous chemotherapy dosing.

Effects of sodium dodecyl sulfate, Sarkosyl and sodium lauroyl glutamate on the structure of proteins monitored by agarose native gel electrophoresis and circular dichroism.

We have studied binding properties of three detergents, i.e., sodium dodecyl sulfate (SDS), Sarkosyl and sodium lauroyl glutamate (SLG), to model proteins based on their effects on electrophoretic mobilities of the proteins using agarose native gel electrophoresis and circular dichroism (CD). This simple technology can evaluate the dissociative properties of bound detergents from the proteins and their effects on protein structure. SDS influenced the electrophoretic mobilities of all model proteins more strongly than the other two detergents, implying a stronger inclination for protein binding and subsequent alterations in protein structure or reductions in activity, which are supported by CD analysis. On the contrary, Sarkosyl and SLG showed weaker binding and interfered less with the structure and biological activities, indicating that these detergents may be useful for protein purification and analysis. It appeared that SLG was weaker in protein binding than Sarkosyl, although the effects of these two detergents appeared to depend on the proteins.

How traditional Chinese exercise (Daoyin) can help COVID-19 patients relieve psychological symptoms: a systematic review and meta-analysis.

Objective: The mental health issues of individuals with coronavirus disease 2019 (COVID-19) are currently widespread. Traditional Chinese exercise (Daoyin) plays an important role in relieving patients' psychological problems. This study aims to assess the efficacy of Daoyin in mitigating mental health issues among individuals diagnosed with COVID-19. Methods: PubMed, the Cochrane library, Embase, CNKI, Wanfang, VIP database, and SinoMed were searched from their inception to October 2023. Two researchers independently selected the eligible studies. The analysis and presentation of the findings were conducted using Review Manager 5.2 software. The data were analyzed using mean difference (MD), inverse variance, and 95% confidence intervals (CIs). Results: A total of 12 studies (N = 1291) were included in this study. The results showed that Daoyin can significantly reduce the scores of the Self-Rating Anxiety Scale (SAS: MD = -13.03, 95% CI -19.56 to -6.49, P<.49,yca Self-Rating Depression Scale (SDS: MD = -11.13, 95% CI -14.56 to -7.71, P<.71,sion Pittsburgh Sleep Quality Index (PSQI: MD = -2.00, 95% CI -5.43 to 1.43, P = 0.25), Hamilton Anxiety Scale (HAMA: MD = -2.42, 95% CI -5.25 to 0.41, P = 0.09), and Hamilton Depression Scale (HAMD: MD = -11.17, 95% CI -25.5 to 3.15, P = 0.13). Conclusion: In COVID-19 patients, Daoyin can alleviate feelings of anxiety and depression, as well as improve sleep quality. The use of Daoyin has no adverse effects and side effects and can reduce the cost of medication. Therefore, Daoyin can be widely promoted. Further research is warranted to analyze the effect of Daoyin on mental health. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42023391845.

Impact of Ultrafiltration on the Physicochemical Properties of Bovine Lactoferrin: Insights into Molecular Mass, Surface Morphology, and Elemental Composition.

The large-scale isolation of bovine lactoferrin (bLF) typically involves using large amounts of concentrated eluents, which might introduce impurities to the final product. Sometimes, protein pre-concentration is required for the greater accuracy of experimental results. In this research, the supplied bLF sample was subjected to additional ultrafiltration (UF) to eliminate possible small impurities, such as salts and peptides of bLF. Beforehand, the basic characterization of native bLF, including surface-charge properties and the structural sensitivity to the various pH conditions, was performed. The study aimed to evaluate the difference in molecular mass, primary structure, surface morphology, and elemental composition of the protein before and after UF. The research was provided by application of spectroscopic, spectrometric, electrophoretic, and microscopic techniques. The evident changes in the surface morphology of bLF were observed after UF, while the molecular masses of both proteins were comparable. According to MALDI-TOF/MS results, UF had a positive impact on the bLF sample representation, improving the identification parameters, such as sequence coverage and intensity coverage.

Identification and Quantification of Extracellular Vesicles: Comparison of SDS-PAGE Analysis and Biosensor Analysis with QCM and IDT Chips.

This study presents and compares two methods for identifying the types of extracellular vesicles (EVs) from different cell lines. Through SDS-PAGE analysis, we discovered that the ratio of CD63 to CD81 in different EVs is consistent and distinct, making it a reliable characteristic for recognizing EVs secreted by cancer cells. However, the electrophoresis and imaging processes may introduce errors in the concentration values, especially at lower concentrations, rendering this method potentially less effective. An alternative approach involves the use of quartz crystal microbalance (QCM) and electroanalytical interdigitated electrode (IDT) biosensors for EV type identification and quantification. The QCM frequency shift caused by EVs is directly proportional to their concentration, while electroanalysis relies on measuring the curvature of the I-V curve as a distinguishing feature, which is also proportional to EV concentration. Linear regression lines for the QCM frequency shift and the electroanalysis curvature of various EV types are plotted separately, enabling the estimation of the corresponding concentration for an unknown EV type on the graphs. By intersecting the results from both biosensors, the unknown EV type can be identified. The biosensor analysis method proves to be an effective means of analyzing both the type and concentration of EVs from different cell lines.

Efficient biosynthesis of D/L-alanine in the recombinant Escherichia coli BL21(DE3) by biobrick approach.

Alanine is the most abundant chiral amino acid that exists into the D-alanine or L-alanine forms with diverse applications in the biomedical, pharmaceutical, plastics, and food industries. D/L-alanine production can be carried out through chemical, microbial fermentation, and biocatalytic methods and not much effective due to complicated processes or purification issues and is still challenging to achieve a higher yield. In the present study, biobrick method was utilized for efficient production of D/L-alanine in the recombinant Escherichia coli BL21(DE3) with tandem three-gene co-expression plasmid. Firstly, the co-expression plasmid pET-22bNS-DadX-Ald-Gdh containing three genes, alanine dehydrogenase (ald), alanine racemase (dadX), and glucose dehydrogenase (gdh) from Bacillus pseudofirmus OF4 were successfully constructed and introduced into the E. coli BL21(DE3) strain. Then, under optimized conditions in the whole-cell biocatalytic reaction [20 mM Na2CO3-NaHCO3 (pH 10.1), 200 mM D-glucose, 200 mM sodium pyruvate, and 200 mM ammonium chloride], the concentration of D-alanine and L-alanine reached the maximum value (6.48 g/L and 7.05 g/L) after 3.0 h reaction time at 37°C under 180 rpm rotation. Meanwhile, promoter replacement experiments and Western blot analysis revealed that the expression level of protein OF4Ald had a significant effect on the production of D/L-alanine, indicating that alanine dehydrogenase might be the rate-limiting enzyme for D/L-alanine synthesis. This study provides a simple, feasible, and efficient biosynthesis process of D/L-alanine, which could explore emerging applications for large-scale production of industrial bioproducts.

Rapid identification of antibody impurities in size-based electrophoresis via CZE-MS generated spectral library.

Methods for the reliable and effective detection and identification of impurities are crucial to ensure the quality and safety of biopharmaceutical products. Technical limitations constrain the accurate identification of individual impurity peaks by size-based electrophoresis separations followed by mass spectrometry. This study presents a size-based electrophoretic method for detecting and identifying impurity peaks in antibody production. A hydrogen sulfide-accelerated degradation method was employed to generate known degradation products observed in bioreactors that forms the basis for size calibration. LabChip GXII channel electrophoresis enabled the rapid (< 1 min) detection of impurity peaks based on size, while capillary zone electrophoresis-mass spectrometry (CZE-MS) facilitated their accurate identification. We combine these techniques to examine impurities resulting from cell culture harvest conditions and forced degradation to assess antibody stability. To mimic cell culture harvest conditions and the impact of forced degradation, we subjected samples to cathepsin at different pH buffers or exposed them to high pH and temperature. Our method demonstrated the feasibility and broad applicability of using a CZE-MS generated spectral library to unambiguously assign peaks in high throughput size-based electrophoresis (i.e., LabChip GXII) with identifications or likely mass of the antibody impurity. Overall, this strategy combines the utility of CZE-MS as a high-resolution separation and detection method for impurities with size-based electrophoresis methods that are typically used to detect (not identify) impurities during the discovery and development of antibody therapeutics.

SDS3 regulates microglial inflammation by modulating the expression of the upstream kinase ASK1 in the p38 MAPK signaling pathway.

BACKGROUND: Microglia, the main innate immune cells in the central nervous system, are key drivers of neuroinflammation, which plays a crucial role in the pathogenesis of neurodegenerative diseases. The Sin3/histone deacetylase (HDAC) complex, a highly conserved multiprotein co-repressor complex, primarily performs transcriptional repression via deacetylase activity; however, the function of SDS3, which maintains the integrity of the complex, in microglia remains unclear. METHODS: To uncover the regulatory role of the transcriptional co-repressor SDS3 in microglial inflammation, we used chromatin immunoprecipitation to identify SDS3 target genes and combined with transcriptomics and proteomics analysis to explore expression changes in cells following SDS3 knocking down. Subsequently, we validated our findings through experimental assays. RESULTS: Our analysis revealed that SDS3 modulates the expression of the upstream kinase ASK1 of the p38 MAPK pathway, thus regulating the activation of signaling pathways and ultimately influencing inflammation. CONCLUSIONS: Our findings provide important evidence of the contributions of SDS3 toward microglial inflammation and offer new insights into the regulatory mechanisms of microglial inflammatory responses.

SBDS Gene Mutation Increases ROS Production and Causes DNA Damage as Well as Oxidation of Mitochondrial Membranes in the Murine Myeloid Cell Line 32Dcl3.

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disease caused by mutation in the Shwachman-Bodian-Diamond syndrome (SBDS) gene. SDS has a variety of clinical features, including exocrine pancreatic insufficiency and hematological dysfunction. Neutropenia is the most common symptom in patients with SDS. SDS is also associated with an elevated risk of developing myelodysplastic syndromes and acute myeloid leukemia. The SBDS protein is involved in ribosome biogenesis, ribosomal RNA metabolism, stabilization of mitotic spindles and cellular stress responses, yet the function of SBDS in detail is still incompletely understood. Considering the diverse function of SBDS, the effect of SBDS seems to be different in different cells and tissues. In this study, we established myeloid cell line 32Dcl3 with a common pathogenic SBDS variant on both alleles in intron 2, 258 + 2T > C, and examined the cellular damage that resulted. We found that the protein synthesis was markedly decreased in the mutant cells. Furthermore, reactive oxygen species (ROS) production was increased, and oxidation of the mitochondrial membrane lipids and DNA damage were induced. These findings provide new insights into the cellular and molecular pathology caused by SBDS deficiency in myeloid cells.

A Microdissection Protocol for Proteogenomic Analysis of Histological Sections to Advance Drug Development.

Combining proteogenomics with laser capture microdissection (LCM) in cancer research offers a targeted way to explore the intricate interactions between tumor cells and the different microenvironment components. This is especially important for immuno-oncology (IO) research where improvements in the predictability of IO-based drugs are sorely needed, and depends on a better understanding of the spatial relationships involving the tumor, blood supply, and immune cell interactions, in the context of their associated microenvironments. LCM is used to isolate and obtain distinct histological cell types, which may be routinely performed on complex and heterogeneous solid tumor specimens. Once cells have been captured, nucleic acids and proteins may be extracted for in-depth multimodality molecular profiling assays. Optimizing the minute tissue quantities from LCM captured cells is challenging. Following the isolation of nucleic acids, RNA-seq may be performed for gene expression and DNA sequencing performed for the discovery and analysis of actionable mutations, copy number variation, methylation profiles, etc. However, there remains a need for highly sensitive proteomic methods targeting small-sized samples. A significant part of this protocol is an enhanced liquid chromatography mass spectrometry (LC-MS) analysis of micro-scale and/or nano-scale tissue sections. This is achieved with a silver-stained one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D-SDS-PAGE) approach developed for LC-MS analysis of fresh-frozen tissue specimens obtained via LCM. Included is a detailed in-gel digestion method adjusted and specifically designed to maximize the proteome coverage from amount-limited LCM samples to better facilitate in-depth molecular profiling. Described is a proteogenomic approach leveraged from microdissected fresh frozen tissue. The protocols may also be applicable to other types of specimens having limited nucleic acids, protein quantity, and/or sample volume.

Detection and Quantitation of Endogenous Membrane-Bound RAS Proteins and KRAS Mutants in Cancer Cell Lines Using 1D-SDS-PAGE LC-MS2.

In healthy cells, membrane-anchored wild-type RAS proteins (i.e., HRAS, KRAS4A, KRAS4B, and NRAS) regulate critical cellular processes (e.g., proliferation, differentiation, survival). When mutated, RAS proteins are principal oncogenic drivers in approximately 30% of all human cancers. Among them, KRAS mutants are found in nearly 80% of all patients diagnosed with RAS-driven malignancies and are regarded as high-priority anti-cancer drug targets. Due to the lack of highly qualified/specific RAS isoform and mutant RAS monoclonal antibodies, there is a vital need for an effective antibody-free approach capable of identifying and quantifying membrane-bound RAS proteins in isoform- and mutation-specific manner. Here, we describe the development of a simple antibody-free protocol that relies on ultracentrifugation to isolate the membrane fraction coupled with single-dimensional (1D) sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to fractionate and enrich membrane-bound endogenous RAS isoforms. Next, bottom-up proteomics that utilizes in-gel digestion followed by reversed-phase high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS2) is used for detection and relative quantitation of all wild-type RAS proteins (i.e., HRAS, KRAS4A, KRAS4B, and NRAS) and corresponding RAS mutants (e.g., G12D, G13D, G12S, G12V). Notably, this simple 1D-SDS-PAGE-HPLC-MS2-based protocol can be automated and widely applied to multiple cancer cell lines to investigate concentration changes in membrane-bound endogenous RAS proteins and corresponding mutants in the context of drug discovery.

Pyranine Interaction with Amines in Micelles.

The fluorescence behavior of pyranine in anionic micellar system of sodium dodecyl sulphate was studied in the presence of selected amines. The amines included cyclopropylamine (CPA), ethylenediamine (EDA), benzylamine (BA), dibutylamine (DBA), cyclohexylamine (CHA), and polyethylenediamine (PEDA). All the studied amines quenched the intensity of pyranine. Study was performed in 0.05 M and 0.1 M SDS. The thermodynamic parameters were determined in order to understand the quenching of pyranine by the studied amines. Change in Gibbs free energy and quenching was found higher in 0.05 M SDS concentration and was found lower when SDS concentration was increased to 0.1 M SDS. Pyranine quenching by the amines studied were treated with an extended Stern-Volmer equation that produced the Stern-Volmer constant ([Formula: see text]). Binding constant (Kb), number of binding stoichiometry (n) and Gibbs free energy change (ΔGbinding) were found higher for lower surfactant concentration as compare to higher surfactant concentration. More negative (-ve) the Gibbs free energies more will be the quenching, higher will be the sensitivity and vice versa. The Gibbs free energies for all the studied amines were found in the order as cyclopropylamine > ethylenediamine > benzylamine > dibutylamine > cyclohexylamine > polyethylenediamine. Fluorescence quenching of pyranine by amines in aqueous SDS is reproducible and is useful for the determination of amines in environmental samples.

Deciphering the impact of nitrogen morphologies distribution on nitrogen and biomass accumulation in tobacco plants.

Background and aims: Nitrogen (N) distribution in plants is intricately linked to key physiological functions, including respiration, photosynthesis, structural development, and nitrogen storage. However, the specific effects of different N morphologies on N accumulation and plant growth are poorly understood. Our research specifically focused on determining how different N morphologies affect N absorption and biomass accumulation. Methods: This study elucidated the impact of different application rates (CK: 0 g N/plant; T1: 4 g N/plant; T2: 8 g N/plant) of N fertilizer on N and biomass accumulation in tobacco cultivars Hongda and K326 at different growth stages. Results: Our findings emphasize the critical role of N distribution in various plant parts, including leaves, stems, and roots, in determining the complex mechanisms of N and biomass accumulation in tobacco. We found that in relation to total N, a greater ratio of water-soluble N (N w) in leaves facilitated N accumulation in leaves. In contrast, an increased ratio of SDS (detergent)-insoluble N (N in-SDS) in leaves and non-protein N (N np) in roots hindered this increase. Additionally, our results indicate that a greater proportion of N np in leaves has a negative impact on biomass accumulation in leaves. Furthermore, elevated levels of N in-SDS, N w, and N np in roots, and N np in leaves adversely affected biomass accumulation in tobacco leaves. The Hongda cultivar exhibited greater biomass and N accumulation abilities as compared to K326. Conclusions: Our findings highlight the significant role of distribution of N morphologies on plant growth, as well as N and biomass accumulation in tobacco plants. Understanding N distribution allows farmers to optimize N application, minimizing environmental losses and maximizing yield for specific cultivars. These insights advance sustainable agriculture by promoting efficient resource use and reducing environmental impact.

Corrigendum: Current phenotypic and genetic spectrum of syndromic deafness in Tunisia: paving the way for precision auditory health.

[This corrects the article DOI: 10.3389/fgene.2024.1384094.].

Exploring cheese and red wine pairing by an in vitro simulation of tasting.

The cheese wine pairing is a beloved combination subject to a certain subjectivity due to sensorial, psychological, chemical, and cultural factors. This work represents a first attempt to explore the in vitro interactions between cheese, wine, and saliva to objectively measure the pairing. Two experimental red wines obtained from the same grape cultivar and four different cheeses were studied for their composition. Binding reactions between wine and cheese were carried out in three simulated tasting trials and, after precipitation, the wine phenolic content, Saliva Precipitation Index (SPI), and total proteins were evaluated. The optimal pairing (OP) was calculated considering the decrease in salivary and cheese proteins by wine, defined as the cleansing effect; the decrease in astringency due to the cheese, measured by the SPI, and the coating fat which would remain in mouth after eating a piece of cheese. Based on obtained results, the semi-hard cheese was identified as the best pairing option for the two experimental red wines. The differences in the phenolic content between the two wines were instead not enough to show a significant influence on the OP. The in vitro cheese wine pairing can contribute to understanding of wine tasting but it is only a part of the puzzle. However, this first contribution paves the way for additional studies on the molecular and chemical interactions involved in aroma and textural perception in simulated trials.

Combining SDS-PAGE to capillary zone electrophoresis-tandem mass spectrometry for high-resolution top-down proteomics analysis of intact histone proteoforms.

Mass spectrometry (MS)-based top-down proteomics (TDP) analysis of histone proteoforms provides critical information about combinatorial post-translational modifications (PTMs), which is vital for pursuing a better understanding of epigenetic regulation of gene expression. It requires high-resolution separations of histone proteoforms before MS and tandem MS (MS/MS) analysis. In this work, for the first time, we combined SDS-PAGE-based protein fractionation (passively eluting proteins from polyacrylamide gels as intact species for mass spectrometry, PEPPI-MS) with capillary zone electrophoresis (CZE)-MS/MS for high-resolution characterization of histone proteoforms. We systematically studied the histone proteoform extraction from SDS-PAGE gel and follow-up cleanup as well as CZE-MS/MS, to determine an optimal procedure. The optimal procedure showed reproducible and high-resolution separation and characterization of histone proteoforms. SDS-PAGE separated histone proteins (H1, H2, H3, and H4) based on their molecular weight and CZE provided additional separations of proteoforms of each histone protein based on their electrophoretic mobility, which was affected by PTMs, for example, acetylation and phosphorylation. Using the technique, we identified over 200 histone proteoforms from a commercial calf thymus histone sample with good reproducibility. The orthogonal and high-resolution separations of SDS-PAGE and CZE made our technique attractive for the delineation of histone proteoforms extracted from complex biological systems.