Retrospective clinical study analysis of skin adverse reactions related to epidermal growth factor receptor inhibitors.

Background: Epidermal growth factor receptor inhibitors (EGFRIs) represent a cornerstone in the targeted therapy of malignant tumors. While effective, dermatological adverse events (dAEs) associated with EGFRIs pose a significant challenge, often necessitating treatment discontinuation due to their severity and potential to impede the continuity of cancer therapy. Despite extensive research, the specific mechanisms and predictors of these adverse events remain poorly understood, particularly in diverse populations. This gap in knowledge underscores the need for targeted studies to better predict and manage these events, enhancing patient outcomes and adherence to life-saving therapies. Methods: This observational study was conducted at The First Affiliated Hospital of Guangxi Medical University, covering cancer patients treated with EGFRIs from 2020 to 2022. We analyzed clinical data including patient demographics, treatment specifics, and the development and timing of dAEs. The study employed SPSS 26.0 software for data analysis, focusing on the incidence of dAEs and factors influencing their occurrence. We used Kaplan-Meier and Cox regression methods to establish a predictive model for dAEs, tracking their onset and impact on treatment continuity. Results: In our study of 120 patients treated with EGFR inhibitors at The First Affiliated Hospital of Guangxi Medical University, we found a high prevalence of dAEs, with 84.2% of patients experiencing such effects. The most common manifestations were papulopustular rashes, observed as pustules in 52.5% and papules in 57.4% of cases, followed by nail lesions in 62.4% of patients, oral or other mucosal ulcers in 34.7%, and hair changes in 26.7%. The median incubation time (MIT) for dAEs was 5 weeks. We identified drug type, ethnicity, and occupation as statistically significant risk factors (P<0.05 for all) that influenced the MIT, which the Cox regression model further identified as protective factors. Nomograms were developed to assess the risk of dAEs, although it is important to note that these models have only been internally validated, lacking external validation data at this stage. Conclusions: The study highlights the high incidence of EGFRIs-associated dAEs, with specific dermatological manifestations posing significant challenges in cancer therapy. The identification of drug type, ethnicity, and occupation as influential factors on the MIT for dAEs informs clinical decisions. Our prediction model serves as a practical tool for evaluating the risk of developing dAEs over time, aiming to optimize patient management and mitigate treatment interruptions.

Study on the anti-cancer activity of α-phenethylamine ferrocenecarboxylic acid co-crystals.

Ferrocene derivatives show a wide range of pharmacological activities in the medical field, especially in the anti-tumor field, and can be used as candidate drugs or lead compounds for the treatment of tumors and other diseases. And α-phenethylamine is an important intermediate for the preparation of fine chemical products. (R)-(+)-1-Phenethylamine ferrocenecarboxylic acid/(S)-(-)-1-phenethylamine ferrocenecarboxylic acid were prepared, named compounds 1 and 2, respectively. Single crystal X-ray diffraction showed that compounds 1 and 2 crystallized in the orthorhombic system space group P21 21 21 , and the crystal structures of compounds 1 and 2 exhibited mirror symmetry. The inhibitory effect of two compounds on SW480, MDA-MB-231, and H1299 cells was tested by MTT colorimetry. The IC50 values of the compounds against cancer cells were also calculated. The anti-cancer effect was more pronounced for compounds in the S-configuration. Compound 2 made the wild-type cancer cells undergo apoptosis, thus preventing cancer; it also had the function of helping the cell gene repair defects.

Leonurus japonicus Houtt. (Motherwort): Systematic research through chemical profiling, stability under controlled conditions and pharmacokinetic analysis on screening Q-markers for quality control.

Leonurus japonicus Houtt. (Motherwort) is the fresh or dried aerial part of Leonurus japonicus Houtt. (Labiaceae), which is widely used in clinical practice and daily life, used to treat gynecological diseases. However, the differences between different parts, single index component in Pharmacopoeias and the less stability of active ingredients affect its clinical efficacy. This study aimed to find the multi-active compounds between different parts of Motherwort to ensure its clinical efficacy, which related to stability and had pharmacokinetic behavior. Firstly, HPLC-Q-TOF-MS/MS was used to analyze the components in vitro and in vivo, as well as multivariate statistical analysis and network pharmacology analysis was conducted to find the significant different components related to activity. Secondly, the content determination methods were established to study the stability of effective components during storage in order to establish the content limit for quality control of Motherwort. Thirdly, UFLC-MS/MS was used to analyze the pharmacokinetic behavior of active components in Motherwort. The results showed that a total of 131 chemical constituents were identified in vitro and 21 prototype absorption compounds and 72 metabolites were found in vivo. Meantime, multivariate statistical analysis and network pharmacology analysis was combined to find that leonurine, stachydrine and trigonelline were activity-related substance, which could be used as active components related to pharmacodynamics in different parts. Then the stability variation trend and content limit of three alkaloids were found, which could be used for the quality control of Motherwort. Furthermore, the results showed that three alkaloids had pharmacokinetic behavior in vivo. 3 alkaloids were screened, which could be used as active components most closely related to pharmacodynamics among different parts. The stable stage, assay tolerance and pharmacokinetic characteristics were studied by the active substances, which could provide a basis for quality control and clinical medication of Motherwort.

Observation of frequency-uncorrelated photon pairs generated by counter-propagating spontaneous parametric down-conversion.

We report the generation of frequency-uncorrelated photon pairs from counter-propagating spontaneous parametric down-conversion in a periodically-poled KTP waveguide. The joint spectral intensity of photon pairs is characterized by measuring the corresponding stimulated process, namely, the difference frequency generation process. The experimental result shows a clear uncorrelated joint spectrum, where the backward-propagating photon has a narrow bandwidth of 7.46 GHz and the forward-propagating one has a bandwidth of 0.23 THz like the pump light. The heralded single-photon purity estimated through Schmidt decomposition is as high as 0.996, showing a perspective for ultra-purity and narrow-band single-photon generation. Such unique feature results from the backward-wave quasi-phase-matching condition and does not has a strict limitation on the material and working wavelength, thus fascinating its application in photonic quantum technologies.

Anti-SARS-CoV-2 activities in vitro of Shuanghuanglian preparations and bioactive ingredients.

Human infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) and there is no cure currently. The 3CL protease (3CLpro) is a highly conserved protease which is indispensable for CoVs replication, and is a promising target for development of broad-spectrum antiviral drugs. In this study we investigated the anti-SARS-CoV-2 potential of Shuanghuanglian preparation, a Chinese traditional patent medicine with a long history for treating respiratory tract infection in China. We showed that either the oral liquid of Shuanghuanglian, the lyophilized powder of Shuanghuanglian for injection or their bioactive components dose-dependently inhibited SARS-CoV-2 3CLpro as well as the replication of SARS-CoV-2 in Vero E6 cells. Baicalin and baicalein, two ingredients of Shuanghuanglian, were characterized as the first noncovalent, nonpeptidomimetic inhibitors of SARS-CoV-2 3CLpro and exhibited potent antiviral activities in a cell-based system. Remarkably, the binding mode of baicalein with SARS-CoV-2 3CLpro determined by X-ray protein crystallography was distinctly different from those of known 3CLpro inhibitors. Baicalein was productively ensconced in the core of the substrate-binding pocket by interacting with two catalytic residues, the crucial S1/S2 subsites and the oxyanion loop, acting as a "shield" in front of the catalytic dyad to effectively prevent substrate access to the catalytic dyad within the active site. Overall, this study provides an example for exploring the in vitro potency of Chinese traditional patent medicines and effectively identifying bioactive ingredients toward a specific target, and gains evidence supporting the in vivo studies of Shuanghuanglian oral liquid as well as two natural products for COVID-19 treatment.

Activated mTOR signaling pathway in myofibers with inherited metabolic defect might be an evidence for mTOR inhibition therapies.

BACKGROUND: Abnormally activated mechanistic target of rapamycin (mTOR) pathway has been reported in several model animals with inherited metabolic myopathies (IMMs). However, the profiles of mTOR pathway in skeletal muscles from patients are still unknown. This study aimed to analyze the activity of mTOR pathway in IMMs muscles. METHODS: We collected muscle samples from 25 patients with mitochondrial myopathy (MM), lipid storage disease (LSD) or Pompe disease (PD). To evaluate the activity of mTOR pathway in muscle specimens, phosphorylation of S6 ribosomal protein (p-S6) and p70S6 kinase (p-p70S6K) were analyzed by Western blotting and immunohistochemistry. RESULTS: Western blotting results showed that p-p70S6K/p70S6K in muscles from LSD and MM was up-regulated when compared with normal controls (NC) (NC vs. LSD, U = 2.000, P = 0.024; NC vs. MM: U = 6.000, P = 0.043). Likewise, p-S6/S6 was also up-regulated in muscles from all three subgroups of IMMs (NC vs. LSD, U = 0.000, P = 0.006; NC vs. PD, U = 0.000, P = 0.006; NC vs. MM, U = 1.000, P = 0.007). Immunohistochemical study revealed that p-S6 was mainly expressed in fibers with metabolic defect. In MM muscles, most p-S6 positive fibers showed cytochrome C oxidase (COX) deficiency (U = 5.000, P = 0.001). In LSD and PD muscles, p-S6 was mainly overexpressed in fibers with intramuscular vacuoles containing lipid droplets (U = 0.000, P = 0.002) or basophilic materials (U = 0.000, P = 0.002). CONCLUSION: The mTOR pathway might be activated in myofibers with various metabolic defects, which might provide evidence for mTOR inhibition therapy in human IMMs.

The inhibitory mechanism of aurintricarboxylic acid targeting serine/threonine phosphatase Stp1 in Staphylococcus aureus: insights from molecular dynamics simulations.

Serine/threonine phosphatase (Stp1) is a member of the bacterial Mg2+- or Mn2+- dependent protein phosphatase/protein phosphatase 2C family, which is involved in the regulation of Staphylococcus aureus virulence. Aurintricarboxylic acid (ATA) is a known Stp1 inhibitor with an IC50 of 1.03 µM, but its inhibitory mechanism has not been elucidated in detail because the Stp1-ATA cocrystal structure has not been determined thus far. In this study, we performed 400 ns molecular dynamics (MD) simulations of the apo-Stp1 and Stp1-ATA complex models. During MD simulations, the flap subdomain of the Stp1-ATA complex experienced a clear conformational transition from an open state to a closed state, whereas the flap domain of apo-Stp1 changed from an open state to a semi-open state. In the Stp1-ATA complex model, the hydrogen bond (H-bond) between D137 and N142 disappeared, whereas critical H-bond interactions were formed between Q160 and H13, Q160/R161 and ATA, as well as N162 and D198. Finally, four residues (D137, N142, Q160, and R161) in Stp1 were mutated to alanine and the mutant enzymes were assessed using phosphate enzyme activity assays, which confirmed their important roles in maintaining Stp1 activity. This study indicated the inhibitory mechanism of ATA targeting Stp1 using MD simulations and sheds light on the future design of allosteric Stp1 inhibitors.

Clinical, Neuroimaging, and Pathological Analyses of 13 Chinese Leigh Syndrome Patients with Mitochondrial DNA Mutations.

BACKGROUND: Leigh syndrome (LS) is a rare disease caused by mitochondrial defects and has high phenotypic and genotypic heterogeneity. We analyzed the clinical symptoms, neuroimaging, muscular histopathology, and genotypes of 13 Chinese LS patients with mitochondrial DNA (mtDNA) mutations. METHODS: Mutations in mtDNA were identified by targeted sequencing. The brain imaging features on magnetic resonance imaging (MRI) were analyzed. The levels of lactate in fasting blood and cerebrospinal fluid (CSF) were routinely tested. The levels of urinary organic acids, plasma amino acids, and acylcarnitines were examined with gas chromatography-mass spectrometry and tandem mass spectrometry. The histopathological traits of skeletal muscles were analyzed under microscope. RESULTS: Among 13 patients, mutations of MT-NDs (n = 8) and MT-ATP6 (n = 4) genes were most common. Strabismus (8/13), muscle weakness (8/13), and ataxia (5/13) were also common, especially for the patients with late-onset age after 2 years old. However, respiratory distress was common in patients with early-onset age before 2 years old. The most frequently affected brain area in these patients was the brain stem (12/13), particularly the dorsal part of midbrain, followed by basal ganglia (6/13), thalamus (6/13), cerebellum (5/13), and supratentorial white matter (2/13). Besides, the elevated lactate levels in CSF (6/6) were more common than those in serum (7/13). However, the analysis of abnormal plasma amino acid and urinary organic acid showed limited results (0/3 and 1/4, respectively). Muscular histopathology showed mitochondrial myopathy in the three late-onset patients but not in the early-onset ones. CONCLUSIONS: Noninvasive genetic screening is recommended for mtDNA mutations in MT-NDs and MT-ATP6 genes in patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory disorder. Furthermore, the lactate detection in CSF and the brain MRI scanning are suggested as the diagnosis methods for LS patients with mtDNA mutations.

Conformation and dynamics of the C-terminal region in human phosphoglycerate mutase 1.

Phosphoglycerate mutase 1 (PGAM1), an important enzyme in glycolysis, is overexpressed in a number of human cancers, thus has been proposed as a promising metabolic target for cancer treatments. The C-terminal portion of the available crystal structures of PGAM1 and its homologous proteins is partially disordered, as evidenced by weak electron density. In this study, we identified the conformational behavior of the C-terminal region of PGAM1 as well as its role during the catalytic cycle. Using the PONDR-FIT server, we demonstrated that the C-terminal region was intrinsically disordered. We applied the Monte Carlo (MC) method to explore the conformational space of the C-terminus and conducted a series of explicit-solvent molecular dynamics (MD) simulations, and revealed that the C-terminal region is inherently dynamic; large-scale conformational changes in the C-terminal segment led to the structural transition of PGAM1 from the closed state to the open state. Furthermore, the C-terminal segment influenced 2,3-bisphosphoglycerate (2,3-BPG) binding. The proposed swing model illustrated a critical role of the C-terminus in the catalytic cycle through the conformational changes. In conclusion, the C-terminal region induces large movements of PGAM1 from the closed state to the open state and influences cofactor binding during the catalytic cycle. This report describes the dynamic features of the C-terminal region in detail and should aid in design of novel and efficient inhibitors of PGAM1. A swing mechanism of the C-terminal region is proposed, to facilitate further studies of the catalytic mechanism and the physiological functions of its homologues.

Sex Determination in Bluegill Sunfish Lepomis macrochirus: Effect of Temperature on Sex Ratio of Four Geographic Strains.

There is increasing evidence that temperature effects on sex ratio in fish species are ubiquitous. Temperature effects on sex ratio could be influenced by parent, strain, and population, whether in fish species with temperature-dependent sex determination or genetic sex determination plus temperature effects. In the present study, effects of genotype-temperature interactions on sex determination in bluegill sunfish were further investigated, based on our previous results, using four geographic strains: Hebron, Jones, Hocking, and Missouri. In the Hebron strain, the two higher-temperature treatment groups (24 °C and 32 °C) produced more males than the low-temperature treatment group (17 °C) from 6 days post-hatching (dph) to 90 dph. In contrast, the low-temperature treatment produced more males than the other two higher-temperature treatments in the Jones strain. No significant effects of temperature on sex ratio were detected in the other two strains. Our results from sex ratio variance in different treatment times suggest that the thermosensitive period of sex differentiation occurs prior to 40 dph. Our results further confirmed that genotype-temperature interactions influence sex determination in bluegill. Therefore, to significantly increase the proportion of males, which grow faster and larger than females, a consumer- and environment-friendly approach may be achieved through selection of temperature sensitivity in bluegill.

Nonuniformity correction for an infrared focal plane array based on diamond search block matching.

In scene-based nonuniformity correction algorithms, artificial ghosting and image blurring degrade the correction quality severely. In this paper, an improved algorithm based on the diamond search block matching algorithm and the adaptive learning rate is proposed. First, accurate transform pairs between two adjacent frames are estimated by the diamond search block matching algorithm. Then, based on the error between the corresponding transform pairs, the gradient descent algorithm is applied to update correction parameters. During the process of gradient descent, the local standard deviation and a threshold are utilized to control the learning rate to avoid the accumulation of matching error. Finally, the nonuniformity correction would be realized by a linear model with updated correction parameters. The performance of the proposed algorithm is thoroughly studied with four real infrared image sequences. Experimental results indicate that the proposed algorithm can reduce the nonuniformity with less ghosting artifacts in moving areas and can also overcome the problem of image blurring in static areas.

[Enhanced reductive decoloration of methylene blue by polyacrylic acid modified zero-valent iron nanoparticles].

Nano zerovalent iron ( NZVI) technology has attracted tremendous amount of interests for degrading a number of environmental contaminants found both in surface water and underground water. However, these nanoscale particles are prone to aggregate, which may result in the decrease of its reactivity in liquid phase. Iron nanoparticles (Fe NPs) modified with polyacrylic acid (PAA) has enhanced the dispersion of NZVI and reduced its agglomeration. For the first time, PAA modified NPs (PAA-Fe NPs) were used for degradation of methylene blue in water phase. The PAA-Fe NPs prepared were characterized in terms of TEM, SEM, XRD and specific surface area. The results indicated that, the surface area of PAA-Fe NPs was increased, compared with unmodified pristine zero-valent iron NPs, and PAA-Fe NPs were smoother with smaller particle size. With addition of 0.1 g x L(-1) of PAA, the decolorization efficiency of methylene blue by PAA-Fe NPs was 98.84% in 60 min, which was 27.32% higher than that of pristine Fe NPs. Decolorization efficiencies were also affected by initial pH value, initial concentration of methylene blue, dosage of PAA-Fe NPs, and degradation temperature. Kinetic analyses based on the experimental data illustrated that the decolorization reaction of methylene blue fitted well to the pseudo first-order kinetics model.

Separation and purification of small peptides from fermented sesame meal and their antioxidant activities.

Protein hydrolysates are widely applied as antioxidants in nutrition, but the potential antioxidant activities of small peptides remain unknown. Therefore, we investigated the antioxidant activities of small peptides isolated from solid-state fermented sesame meal via Sephadex G-15 chromotography. The scavenging capacities for 2, 2- diphenylpicrylhydrazyl (DPPH) and hydroxyl (•OH) radicals as well as the total reducing capacity were determined. The in vivo antioxidant activity was determined upon 30-d intragastric administration of the isolated small peptides (tripeptide, tetrapeptide, and hexapeptide) at different doses (0.1, 0.2, and 0.4 g/kg•d) in healthy Kunming mice. The results showed that the DPPH and •OH scavenging rates of the three peptides exceeded 80%. The total reducing activities of 4 mg/mL tetrapeptide or hexapeptide and 2 mg/mL tripeptide were comparable to that of 0.5 mg/mL glutathione. In mice fed sesame peptides, malondialdehyde levels in the serum and liver were lower than those in controls, whereas the activities of liver superoxide dismutase and glutathione peroxidase were significantly higher than those in controls (P<0.05). The antioxidant activity of tripeptide was significantly higher than those of tetrapeptide and hexapeptide (P<0.05). In conclusion, small peptides extracted from solid-state fermented sesame meal possess strong antioxidant activities that increase with decreasing peptide molecular weight.

Molecular insights into the D1R agonist and D2R/D3R antagonist effects of the natural product (-)-stepholidine: molecular modeling and dynamics simulations.

(-)-Stepholidine (l-SPD), an active ingredient of the Chinese herb Stephania, is the first compound found to have a dual function as a dopamine receptor D1 agonist and D2 antagonist. The preliminary dynamical behaviors of D1R and D2R and their interaction modes with l-SPD were investigated in our previous study. Recently, the pharmacological effect of l-SPD on D3R was elucidated as an antagonist. This new discovery in combination with the explosion of structural biology in GPCR superfamily prompted us to perform a more comprehensive investigation on the special pharmacological profiles of l-SPD on dopamine receptors. In this study, the integration of homology modeling, automated molecular docking, and MD simulations was used to probe the agonistic and antagonistic mechanism of l-SPD on D1R, D2R, and D3R. Our analyses showed that hydrogen bonding of the hydroxyl group on the D ring of l-SPD with side chain of N6.55 which, in combination with hydrophobic stacking between I3.40, F6.44 and W6.48, is the key feature to mediate the agonist effect of l-SPD on D1R, whereas the absence of hydrophobic stacking between I3.40, F6.44, and W6.48 in D2R and D3R excludes receptor activation. Finally, the agonistic and antagonistic mechanisms of l-SPD and an activation model of D1R were proposed on the basis of these findings. The present study could guide future experimental works on these receptors and has the significance to the design of functionally selective drugs targeting dopamine receptors.

Pharmacophore-based virtual screening versus docking-based virtual screening: a benchmark comparison against eight targets.

AIM: This study was conducted to compare the efficiencies of two virtual screening approaches, pharmacophore-based virtual screening (PBVS) and docking-based virtual screening (DBVS) methods. METHODS: All virtual screens were performed on two data sets of small molecules with both actives and decoys against eight structurally diverse protein targets, namely angiotensin converting enzyme (ACE), acetylcholinesterase (AChE), androgen receptor (AR), D-alanyl-D-alanine carboxypeptidase (DacA), dihydrofolate reductase (DHFR), estrogen receptors alpha (ERalpha), HIV-1 protease (HIV-pr), and thymidine kinase (TK). Each pharmacophore model was constructed based on several X-ray structures of protein-ligand complexes. Virtual screens were performed using four screening standards, the program Catalyst for PBVS and three docking programs (DOCK, GOLD and Glide) for DBVS. RESULTS: Of the sixteen sets of virtual screens (one target versus two testing databases), the enrichment factors of fourteen cases using the PBVS method were higher than those using DBVS methods. The average hit rates over the eight targets at 2% and 5% of the highest ranks of the entire databases for PBVS are much higher than those for DBVS. CONCLUSION: The PBVS method outperformed DBVS methods in retrieving actives from the databases in our tested targets, and is a powerful method in drug discovery.

Novel cyclophilin D inhibitors derived from quinoxaline exhibit highly inhibitory activity against rat mitochondrial swelling and Ca2+ uptake/ release.

AIM: To investigate methods for identifying specific cyclophilin D (CypD) inhibitors derived from quinoxaline, thus developing possible lead compounds to inhibit mitochondrial permeability transition (MPT) pore opening. METHODS: Kinetic analysis of the CypD/inhibitor interaction was quantitatively performed by using surface plasmon resonance (SPR) and fluorescence titration (FT) techniques. IC(50) values of these inhibitors were determined by PPIase inhibition activity assays. RESULTS: All the equilibrium dissociation constants (KD) of the seven compounds binding to CypD were below 10 mumol/L. The IC(50) values were all consistent with the SPR and FT results. Compounds GW2, 5, 6, and 7 had high inhibition activities against Ca(2+)-dependent rat liver mitochondrial swelling and Ca(2+) uptake/release. Compound GW5 had binding selectivity for CypD over CypA. CONCLUSION: The agreement between the measured IC(50) values and the results of SPR and FT suggests that these methods are appropriate and powerful methods for identifying CypD inhibitors. The compounds we screened using these methods (GW1-7) are reasonable CypD inhibitors. Its potent ability to inhibit mitochondrial swelling and the binding selectivity of GW5 indicates that GW5 could potentially be used for inhibiting MPT pore opening.