Background 900 MHz radiofrequency radiation (RF) is a commonly used frequency in modern wireless communication devices, and its potential health effects have drawn much attention, especially its impact on bone metabolism, which has not been fully clarified. Objective To investigate the effects of 900 MHz RF on the bone tissue and osteoblast senescence of mice, as well as the dose-effect relationship. Methods In vivo, 3-month-old female C57BL/6 mice were divided into five groups (n=10): sham exposure, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and D-galactose positive control (D-gal). Treatments were administered for 4 h per day for 28 d. Bone mineral density (BMD) and microstructure, including bone volume (BV), tissue volume (TV), bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular separation (Tb.Sp), and trabecular thickness (Tb.Th), were assessed by Micro-CT; bone morphology was examined after hematoxylin and eosin (HE) staining; osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-κΒ ligand (RANKL) expression was detected by immunohistochemistry; serum OPG, tartrate-resistant acid phosphatase 5b (TRACP-5b), plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6), and C-X-C motif chemokine ligand 15 (CXCL15) levels were measured by enzyme-linked immunosorbent assay (ELISA); mRNA expression of Tp53, Cdkn1a, and Cdkn2a in bone tissue was analyzed by reverse transcription polymerase chain reaction (RT-PCR). In vitro, MC3T3-E1 pre-osteoblasts were grouped into sham, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and H₂O₂ control, groups, and were exposed for 4 h per day for 5 d. Cell morphology was observed by microscopy; viability was tested by cell counting kit-8 (CCK-8); senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining; P53 and P21 protein expression was detected by Western blot; Tp53 and Cdkn1a mRNA levels were measured by RT-PCR. Results In vivo, RF at each dose significantly reduced the BMD of the mice's femurs and the bone microstructure parameters, such as BV/TV, Tb.N, and Tb.Th (P<0.05). Among them, Tb.Sp only increased in the 150 μW·cm⁻² RF group (P<0.05), with a looser bone network; fewer, sparser trabeculae and increased marrow fat were observed after HE staining; down-regulated OPG and up-regulated RANKL expression levels were observed by immunohistochemistry; the ELISA test revealed that the serum OPG levels in the 150 μW·cm⁻² RF group and the 450 μW·cm⁻² RF group of mice were significantly decreased (P<0.05), while the indicator in the 50 μW·cm⁻² RF group showed a decreasing trend but the difference was not statistically significant (P>0.05), TRACP-5b rose, and PAI-1, IL-6, and CXCL15 levels increased (P<0.05); the RT-PCR results showed thatTp53, Cdkn1a, and Cdkn2a mRNA expression was upregulated (P<0.05). In vitro, radiofrequency radiation induced cell flattening, reduced viability (P<0.05), increased SA-β-gal-positive cells (P<0.05), and upregulated P53, P21, Tp53, and Cdkn1a expression (P<0.05). Conclusion 900 MHz RF disrupts bone metabolism in mice by inhibiting bone formation, promoting resorption, and inducing osteoblast senescence, accelerating bone aging. The 150 μW·cm⁻² RF dose exhibits the most pronounced effect, reflecting a nonlinear “window effect,” highlighting potential health risks.

Activation of the heart normally begins in the sinoatrial node (SAN). Electrical impulses spontaneously released by SAN pacemaker cells (SANPCs) trigger the contraction of the heart. However, the cellular nature of SANPCs remains controversial. Here, we report that SANPCs exhibit glutamatergic neuron-like properties. By comparing the single-cell transcriptome of SANPCs with that of cells from primary visual cortex in mouse, we found that SANPCs co-clustered with cortical neurons. Tissue and cellular imaging confirmed that SANPCs contained key elements of glutamatergic neurotransmitter system, expressing genes encoding glutamate synthesis pathway (Gls), ionotropic and metabotropic glutamate receptors (Grina, Gria3, Grm1 and Grm5), and glutamate transporters (Slc17a7). SANPCs highly expressed cell markers of glutamatergic neurons (Snap25 and Slc17a7), whereas Gad1, a marker of GABAergic neurons, was negative. Functional studies revealed that inhibition of glutamate receptors or transporters reduced spontaneous pacing frequency of isolated SAN tissues and spontaneous Ca

The main constituents of a typical medicinal herb,Polygonum muMflorum (Heshouwu in Chinese),that induces idiosyncratic liver injury remain unclear.Our previous work has shown that cotreatment with a nontoxic dose of lipopolysaccharide (LPS) and therapeutic dose of Heshouwu can induce liver injury in rats,whereas the solo treatment cannot induce observable injury.In the present work,using the constituent "knock-out" and "knock-in" strategy,we found that the ethyl acetate (EA) extract of Heshouwu displayed comparable idiosyncratic hepatotoxicity to the whole extract in LPS-treated rats.Results indicated a significant elevation of plasma alanine aminotransferase,aspartate aminotransferase,and liver histologic changes,whereas other separated fractions failed to induce liver injury.The mixture of EA extract with other separated fractions induced comparable idiosyncratic hepatotoxicity to the whole extract in LPS-treated rats.Chemical analysis further revealed that 2,3,5,4'-tetrahydroxy trans-stilbene-2-O-β-glucoside (trans-SG) and its cis-isomer were the two major compounds in EA extract.Furthermore,the isolated cis-,and not its trans-isomer,displayed comparable idiosyncratic hepatotoxicity to EA extract in LPS-treated rats.Higher contents of cis-SG were detected in Heshouwu liquor or preparations from actual liver intoxication patients associated with Heshouwu compared with general collected samples.In addition,plasma metabolomics analysis showed that cis-SG-disturbing enriched pathways remarkably differed from trans-SG ones in LPS-treated rats.All these results suggested that cis-SG was closely associated with the idiosyncratic hepatotoxicity of Heshouwu.Considering that the cis-trans isomerization of transSG was mediated by ultraviolet light or sunlight,our findings serve as reference for controlling photoisomerization in drug discovery and for the clinical use of Heshouwu and stilbene-related medications.

BACKGROUND:Adult cardiomyocytes show no regenerative ability, and celltherapy for myocardial regeneration and repair may improve myocardial ischemic injury function. OBJECTIVE:To confirm the effect and reveal the mechanism of bone marrow mesenchymal stem cells (BMSCs) on acute myocardial infarction (AMI). METHODS:BMSCs were isolated, cultured from bone marrow of Sprague-Dawley rats using density gradient centrifugation. AMI models were produced in 20 rats by ligating the left anterior descending (LAD) coronary artery, and randomly divided into model group and BMSCs group. In the BMSCs group, cells were subsequently injected with a sterile microinjection via the tail vein. RESULTS AND CONCLUSION:Six months postoperatively, the cardiac function was improved, the vessel density was increased, the percentage of apoptotic cells was decreased in the BMSCs group than that in the model group;the expression levels of inflammatory factors, including vascular endothelial growth factor, von Wil ebrand factor, transforming growth factor 3β, and interleukin-1βmRNA were significantly improved in the BMSCs group than that in the model group. These results showed that BMSCs can protect the myocardium from AMI by regulating the secretion of inflammatory cytokines and angiogenic factors.

Objective To develop a phenylketonuria (PKU) screening method based on a compact disk (CD) type microfluidic chip capable of generating reciprocating flow within the microchannels that facilitate rapid DNA hybridization. Methods This microfluidic device consists of a two-layer structure: a polydimethylsiloxane (PDMS) top layer containing 12 DNA hybridization microchannels, and a bottom glass layer with immobilized hydrogel conjugated DNA arrays. The DNA arrays included R243Q, V245V and the blank control probes. When the CD device was spun, the PCR products were driven into the hybridization channel by centrifugal force. When the rotation of the CD device was stopped, capillary force pulled the PCR products solution to flow back to the channel. After the on-chip hybridization, the hybridization signals were captured on a fluorescence microscope. The specificity, detection limitation and reproducibility of this device were evaluated. Thirty DNA samples from pregnant women with suspected PKU were detected by this device.Then the results were compared with DNA sequencing results. Results With the compact disk type microfluidic chip, the hybridization time could be reduced to 15 min, sample consume could be as low as 1. 5 μl and the detection limitation was 0. 7 ng/μl. With the chip based method, samples of PKU patients and healthy controls were detected and the results were consistent with DNA sequencing results. Five different batches of chips and five micro-channels of each chip were selected to test one PKU patients with V245V mutation. All the results were positive, indicating good reproducibility. Four cases of V245V mutation and 1 case of R243Q mutation were found in 30 suspected PKU carried pregnant women. Conclusion The compact disk microfluidic device has advantages of simple, rapid and highly sensitive, thus is well suited to PKU screening.

Objective To discuss the clinical effect of combination therapy under the theory of "treating soft tissue for bone disease" on knee osteoarthritis.Methods The 160 cases were randomly divided into control group(80 cases) and experimental group(80 cases).The control group was treated by diclofenac sodium sustained release capsules(per os) and sodium hyaluronate(intra-joint injection).The experimental group was treated by traction,steaming and washing,massage,needle-knife therapy,manipulation on soft tissues for loosening the joint,and orthepedic insoles.The course of treatment was 3 weeks.The effect was evaluated according to Lysholm Score,knee movement and subjective satisfaction after the follow-up for 6 months.Results Of the 154 cases completed the study(control group 75 cases and experimental group 79 cases),the Lysholm Score and knee movement had a very significant improvement(P