Synergistic acceleration of machine learning and molecular docking for prostate-specific antigen ligand design.

Prostate-specific antigen (PSA) serves as a critical biomarker for the early detection and continuous monitoring of prostate cancer. However, commercial PSA detection methods primarily rely on antigen-antibody interactions, leading to issues such as high costs, stringent storage requirements, and potential cross-reactivity due to PSA variant sequence homology. This study is dedicated to the precise design and synthesis of molecular entities tailored for binding with PSA. By employing a million-level virtual screening to obtain potential PSA compounds and effectively guiding the synthesis using machine learning methods, the resulting lead compounds exhibit significantly improved binding affinity compared to those developed before by researchers using high-throughput screening for PSA, substantially reducing screening and development costs. Unlike antibody detection, the design of these small molecules offers promising avenues for advancing prostate cancer diagnostics. Furthermore, this study establishes a systematic framework for the rapid development of customized ligands that precisely target specific protein entities.

An environmentally insensitive fluorescent probe for G4 DNA detection: Design, synthesis, and mechanism studies.

G4 DNA structure highly localized to functionally important sites within the human genome, has been identified as a biomarker for regulation of multiple biological processes. Identification G4-responsive fluorescence probes has broad application prospects for addressing G4 biological functions, as well as developing of new families of anticancer drugs. However, some currently designed G4 DNA probes may suffer from serious solvent-dependent effect, and cause unspecific fluorescence that masks the specific signal from G4 DNA. Herein, with a bulky imidazole-cored molecular rotor fusing in D-A building block of carbazole-pyridinium, we constructed a new probe ACPS. This new probe with desirable environmentally insensitive property exhibited a "fluorescence-off" state in various polarity solvents. In the presence of G4 DNA, the intra-molecular rotations would be restricted, triggering intense fluorescence enhancement. Especially, probe ACPS bound to G4 DNA structures with superior selectivity, exhibiting much weaker fluorescence response in the presence of non-G4 DNA structures. This probe was also able to realize fluorescence visualization in cell imaging. Collectively, the probe design strategy eliminates the background fluorescence caused by uncontrollable environmental polarity change, thereby achieving high-fidelity sensing G4 DNA structures in complicated systems.

Selective c-MYC G4 DNA recognition based on a fluorescent light-up probe with disaggregation-induced emission characteristics.

The c-MYC promoter is well-known as an important oncogene, the overexpression of which leads to ∼80% of all solid tumors. The four-stranded G4 present in the c-MYC promoter has been shown to play a pivotal role in the regulation of c-MYC transcription. Accordingly, strategies employed for c-MYC G4 DNA sensing have implications for the detection of many human pathologies. However, achieving specificity toward c-MYC G4 over other structurally similar G4s is a challenging task. Here, a supramolecular strategy that relies on the recognition-driven disaggregation of a novel BODIPY probe is outlined. The synthesized probe remained almost non-fluorescent in aqueous media in the aggregation state. Of all the tested G4 and non-G4 DNAs, only c-MYC triggered probe disaggregation and induced a significant increase in fluorescence intensity. The binding details discussed here suggest the basis for the recognition of a particular G4 structure, thus opening up a new way for the design and development of sequence-selective supramolecular G4 probes with desired properties.

Design, synthesis and mechanistic studies of a TICT based fluorogenic probe for lighting up protein HSA.

Human serum albumin (HSA) in blood serves as an important biomarker for clinical diagnosis, and fluorescence sensing method has attracted extensive attention. In this work, a small organic molecule probe, YS8, involving twisted intramolecular charge transfer (TICT) characteristic, was designed and investigated to detect HSA. YS8 kept silent state in fluorescence under physiological conditions, but the encapsulation of YS8 in the hydrophobic subdomain IB region of HSA inhibited the TICT state and produced a clear light-up fluorescent signal. Especially, YS8 was demonstrated to be an efficient fluorogenic probe to discriminate HSA from other proteins including the bovine serum albumin (BSA). Moreover, YS8/HSA complex could be applied in fluorescence imaging in living cells and is also useful in the study of artificial fluorescent protein (AFP).

Lipopolysaccharide inhibits triglyceride synthesis in dairy cow mammary epithelial cells by upregulating miR-27a-3p, which targets the PPARG gene.

The fat content of milk determines the quality of milk, and triglycerides are the major components of milk fat. Milk fat synthesis is regulated by many factors. Lipopolysaccharide (LPS) has been shown to inhibit milk fat synthesis in bovine mammary epithelial cells, but research on the underlying mechanisms has been limited. MicroRNA (miRNA) are involved in many physiological processes, but there have been few studies on their regulation in milk fat synthesis. In this study, we aimed to investigate whether LPS upregulates miR-27a-3p, which targets PPARG, thereby inhibiting the synthesis of triglycerides in a dairy cow mammary epithelial cell line (MAC-T). After LPS stimulation of MAC-T cells, PPARG gene expression and milk fat synthesis were inhibited. TargetScan software was used to predict miRNA targeting PPARG, and miR-27a-3p was selected as a candidate. A dual luciferase reporter assay further confirmed the targeting connection between miR-27a-3p and the PPARG gene. To investigate the functions of miR-27a-3p, miR-27a-3p mimic and inhibitors were transfected into MAC-T cells. The mRNA and protein levels of PPAR-γ were negatively correlated with the expression of miR-27a-3p. Lipid droplet accumulation and triglyceride synthesis were also negatively correlated with miR-27a-3p expression. Inhibition of miR-27a-3p partially reversed the LPS-induced decreases in PPARG expression and milk fat synthesis. In summary, our results reveal that LPS can inhibit MAC-T cell milk fat synthesis by upregulating miR-27a-3p, which targets the PPARG gene.

Carbazole-based fluorescent probes for G-quadruplex DNA targeting with superior selectivity and low cytotoxicity.

G-quadruplex DNA plays a very important role in clinical diagnosis and fluorescence analysis has attracted extensive attention. A class of carbazole-based fluorescent probes for the detection of G-quadruplex DNA was established in this work. In this system, the installation of an oligo(ethylene glycol) chain on the scaffold will improve the water-solubility and biocompatibility. The presence of styrene-like different side groups could tune the selectivity toward G-quadruplex DNA binding. Results revealed that the substitution pattern and position gave a great influence on the ability for the discrimination of the G-quadruplex from other DNA structures. Especially, probe E1 bound to G-quadruplex DNA with superior selectivity, which exhibiting almost no fluorescence response in the presence of non-G-quadruplex DNA structures. Comprehensive analyses revealed that E1 could bind both ends of the G-quadruplex, resulting in a significant increase of fluorescence emission intensity. Cellular uptake assay suggested that E1 could pass through membrane and enter living cells with low cytotoxicity.

Synthesis, G-Quadruplex DNA binding and cytotoxic properties of naphthalimide substituted styryl dyes.

G-Quadruplex DNAs, formed by G-rich DNA sequences in human genes, are promising targets for design of cancer drugs. In this study, two naphthalimide substituted styryl dyes with different sizes of aromatic groups were synthesized. The spectral analysis showed that the dye X-2 with a large aromatic group formed aggregates in buffer solution displaying very weak fluorescence intensity, and disaggregated in the presence of G-Quadruplex DNAs with large intensity enhancements (up to ~1800 fold). Moreover, X-2 displayed good selectivity to G-Quadruplex DNAs. In contrast, dye X-3 with the smaller aromatic group had much lower fluorescence enhancements and poor selectivity to G-Quadruplex DNAs, suggesting that the suitably sized aromatic ring was essential for the interaction with G-Quadruplex. Further binding studies suggested that X-2 mainly bound on G-quartet surface through end-stacking mode. Cytotoxicity assay showed that both of the two dyes showed good anti-proliferative activities against the cancer cell lines and less cytotoxicity in non-malignant cell lines, which were better than a standard drug 5-fluorouracil. In addition, living cell imaging was also studied and demonstrated the potential applications of the new dye X-2 in bioassays and cell imaging.

Conjugating a groove binder analogue to a styryl-quinolinium scaffold for the light-up detection of duplex and G-Quadruplex DNA with different binding modes.

The rational design of novel small molecules, which can target specific DNA sequences or secondary structural DNAs, is one of the most important goals in medicinal chemistry. Also the studies of DNA binding potency which can give fundamental insight into binding mechanisms and specificity are essential. In this paper, a N-methylated quinolinium probe NSQ functionalized with a G-Quadruplex DNA groove binder analogue was designed and synthesized. NSQ was found to express selective and sensitive for "light-up" detection of both G-Quadruplex and duplex DNAs over RNA and other biomolecules. The characteristics of NSQ and its interactions with DNAs were comprehensively evaluated by means of fluorescence, UV-Vis, circular dichroism, FID assay, DFT calculation and molecular docking. NSQ exhibited higher binding affinity to G-Quadruplex than to duplex DNA. Binding mechanism analysis indicated NSQ interacted with G-Quadruplex DNA mainly through end-stacking mode, while bound with duplex DNA into the minor groove of AT-rich regions. Further, NSQ exhibited potent in vitro anti-tumor activity, and to elucidate the cellular applications, confocal cell imaging was carried out and validated its mainly nuclear localization.

The Association Between Perceived Stress and Hypertension Among Asian Americans: Does Social Support and Social Network Make a Difference?

Prior research suggests that stress plays role in the etiology and progression of hypertension. To lend a more accurate depiction of the underlying mechanisms between stress and hypertension, this study aims to assess the associations between perceived stress and hypertension across varying levels of social support and social network among Asian Americans. We conducted a cross-sectional study using data on 530 Chinese, Korean and Vietnamese Americans recruited from a liver cancer prevention program in the Washington D.C.-Baltimore metropolitan area. Hypertension prevalence was 29.1%. Individuals with high perceived stress were 61% more likely to have hypertension compared to those with low levels of perceived stress (odds ratio 1.61, 95% confidence interval 1.15, 2.46). There was no evidence that social support and social network acted as effect modifiers. Social support had a direct beneficial effect on hypertension, irrespective of whether individuals were under stress. The relationship between perceived stress and hypertension was modified by gender and ethnicity whereby a significant positive association was only observed among male or Chinese participants. Our study highlights the importance of understanding the associations between stress, social support, and hypertension among Asian American subgroups. Findings from the study can be used to develop future stress management interventions, and incorporate culturally and linguistically appropriate strategies into community outreach and education to decrease hypertension risk within the Asian population.

miR-454 regulates triglyceride synthesis in bovine mammary epithelial cells by targeting PPAR-γ.

Triglycerides account for 99% of milk fat and play a central role in determining dairy product quality. Many factors influence triglyceride synthesis and milk fat secretion. MicroRNAs have been verified to be involved in numerous biological processes, but little is known about their roles in milk fat biosynthesis. In this study, we aim to explore whether miR-454 could regulate triglyceride synthesis in bovine mammary epithelial cells (BMECs) by targeting PPAR-γ. A luciferase reporter assay showed that the predicted target site was correct and that miR-454 and PPAR-γ had a direct interaction. In addition, miR-454 mimics and inhibitors were transfected into BMECs. The results showed that both the mRNA and protein levels of PPAR-γ were negatively correlated with miR-454 expression. Fat droplet accumulation and triglyceride production were also inversely correlated with miR-454 expression. Our results indicate that miR-454 regulates triglyceride synthesis by directly targeting the PPAR-γ 3' UTR in BMECs, suggesting that miR-454 could potentially be a new factor to elevate dairy product quality.

Tuning the selectivity of N-alkylated styrylquinolinium dyes for sensing of G-quadruplex DNA.

Selective and sensitive detection of G-quadruplex DNA structures is an important issue and attracts extensive interest. To this end, numerous small molecular fluorescent probes have been designed. Here, we present a series of N-alkylated styrylquinolinium dyes named Ls-1, Ls-2 and Ls-3 with varying side groups at the chain end. We found that these dyes exhibited different binding behaviors to DNAs, and Ls-2 with a sulfonato group at the chain end displayed sensitivity and selectivity to G-quadruplex DNA structures in vitro. The characteristics of this dye and its interaction with G-quadruplex DNA were comprehensively investigated by means of UV-vis spectrophotometry, fluorescence, circular dichroism and molecular docking. Furthermore, confocal fluorescence images and MTT assays indicated dye Ls-2 could pass through membrane and enter the living HepG2 cells with low cytotoxicity.

[Advances in endoscopic technology for the treatment of thoracic spinal stenosis].

Due to the special anatomical characteristics of thoracic spine, surgery is the only effective way to treat thoracic spinal stenosis. Traditional open surgery is highly traumatic and risky, but it is still regarded as the gold standard for the treatment of the disease. With the development of computer and endoscopic technology, endoscopic technology represented by transforaminal endoscopic surgical system has been widely used in the treatment of cervical and lumbar vertebral diseases, and has achieved good results in recent 10 years. On this basis, domestic and foreign experts have applied endoscopic techniques to the treatment of thoracic spinal stenosis and also achieved good results. The development of endoscopic techniques in the treatment of thoracic spinal stenosis was summarized and reviewed in this paper.

Biomarker and competing endogenous RNA potential of tumor-specific long noncoding RNA in chromophobe renal cell carcinoma.

BACKGROUND: Accumulating evidence suggests long noncoding RNAs (lncRNAs) play important roles in the initiation and progression of cancers. However, their functions in chromophobe renal cell carcinoma (chRCC) are not fully understood. METHODS: We analyzed the expression profiles of lncRNA, microRNA, and protein-coding RNA, along with the clinical information of 59 primary chRCC patients collected from The Cancer Genome Atlas database to identify lncRNA biomarkers for prognosis. We also constructed an lncRNA-microRNA-mRNA coexpression network (competitive endogenous RNAs network) by bioinformational approach. RESULTS: One hundred and forty-two lncRNAs were found to be differentially expressed between the cancer and normal tissues (fold change ≥1.5, P<0.001). Among them, 12 lncRNAs were also differentially expressed with the corresponding clinical characteristics (fold change ≥1.5, P<0.01). Besides, 7 lncRNAs (COL18A1-AS, BRE-AS1, SNHG7, TMEM51-AS1, C21orf62-AS1, LINC00336, and LINC00882) were identified to be significantly correlated with overall survival (log-rank P<0.05). A competitive endogenous RNA network in chRCC containing 16 lncRNAs, 18 miRNAs, and 168 protein-coding RNAs was constructed. CONCLUSION: Our results identified specific lncRNAs associated with chRCC progression and prognosis, and presented competing endogenous RNA potential of lncRNAs in the tumor.

Effects of Adenovirus-Mediated Hepatocyte Growth Factor Gene Therapy on Postinfarct Heart Function: Comparison of Single and Repeated Injections.

Clinical trials testing the effects of a single injection of adenovirus carrying the human hepatocyte growth factor gene (Ad-HGF) in patients with chronic ischemic heart failure failed to show consistent improvements in cardiac function. The aim of this study was to evaluate the efficacy of repeated injections of Ad-HGF in a rat model of postinfarct heart failure. Ad-HGF or Ad-green fluorescent protein (GFP) was administered to Sprague Dawley rat models of postinfarct heart failure via single or fractional repeated intrapericardial injection. Heart function was monitored by magnetic resonance imaging for 4 and 8 weeks after injections. The expression of HGF or factor VIII/Ki-67 was evaluated by Western blot assay or immunofluorescence. We found that Ad-HGF gene expression could be prolonged in vivo by repeated injections and that cardiac function was significantly improved in the Ad-HGF repeat-injection group compared with the Ad-HGF single-injection group. Newly formed capillary density was similarly higher in the Ad-HGF repeat-injection group compared with that in the Ad-HGF single-injection group. We therefore conclude that fractional repeated injections of Ad-HGF may represent a promising therapeutic strategy to improve cardiac function in the setting of postinfarct heart failure.

Severe iron deficiency is associated with a reduced conception rate in female rats.

BACKGROUND/AIMS: Iron deficiency is a global nutritional disorder, especially for pregnant women. There is a close relationship between deficiency in trace elements and unexplained infertility in females. However, the relationship between iron deficiency and unexplained infertility has not been determined. This study was designed to determine the effect of iron deficiency on conception in a rat model. METHODS: Female rats were randomly divided into two groups (n = 15 each): an iron-deficiency group fed a low iron diet and a normal control group. Both groups of female rats were mated with healthy male rats after the iron-deficiency model was established. RESULTS: Iron-deficient rats developed white skin and eyes, hair loss, and weight loss. Hemoglobin levels and red blood cell count were significantly lower than in controls, showing successful establishment of the iron-deficiency model. There was a significantly lower conception rate in the iron-deficiency group; there also appeared to be a disruption of estrus and a delay in conception in the iron-deficiency group. CONCLUSIONS: Severe iron deficiency has a significant influence on fertility, and may be an important factor in unexplained infertility. Further research on the role of iron in conception is warranted.