[Research Progress on Localization of Pulmonary Nodules].

With the widespread adoption of low-dose computed tomography (LDCT) and advancements in computed tomography image resolution, the detection rate of pulmonary nodules, especially smaller ones, has significantly improved. The risk of developing malignant tumors increases with the pulmonary nodule diameter. Video-assisted thoracoscopic surgery (VATS) stands out as the preferred surgical method. The accurate localization of pulmonary nodules is crucial for the success of VATS and remains a significant challenge for thoracic surgeons. Currently, commonly employed localization methods include CT-guided percutaneous positioning, bronchoscope-guided positioning, intraoperative ultrasound positioning, augmented reality (AR), and 3D print-assisted positioning. This review explores recent research progress, highlights the strengths and weaknesses of various pulmonary nodule localization methods. The aim is to provide valuable insights for clinical applications and guide future developments in this field.

The Fabrication of Ultrahigh-Strength Steel with a Nanolath Structure via Quenching-Partitioning-Tempering.

A novel low-alloy ultrahigh-strength steel featuring excellent mechanical properties and comprising a nanolath structure was fabricated in this work using a quenching-partitioning-tempering (Q-P-T) process. The Q-P-T process comprised direct quenching and an isothermal bainitic transformation for partitioning after thermo-mechanical control processing (online Q&P) and offline tempering (reheating and tempering). The ultrafine nanolath martensite/bainite mixed structure, combined with residual austenite in the form of a thin film between the nanolaths, was formed, thereby conferring excellent mechanical properties to the steel structures. After the Q-P-T process, the yield and tensile strengths of the steels reached 1450 MPa and 1726 MPa, respectively. Furthermore, the Brinell hardness and elongation rate were 543 HB and 11.5%, respectively, with an average impact energy of 20 J at room temperature.

Development of a bioactive silk fibroin bilayer scaffold for wound healing and scar inhibition.

In cases of deep skin defects, spontaneous tissue regeneration and excessive collagen deposition lead to hyperplastic scars. Conventional remedial action after scar formation is limited with a high recurrence rate. In this study, we designed a new artificial skin bilayer using silk fibroin nanofibers films (SNF) as the epidermis, and silk fibroin (SF) / hyaluronic acid (HA) scaffold as the dermal layer. The regenerated SF film was used as a binder to form a functional SNF-SF-HA bilayer scaffold. The bilayer scaffold showed high porosity, hydrophilicity, and strength, and retained its shape over 30 days in PBS. In vitro, human umbilical vein endothelial cells were seeded into the bilayer scaffold and showed superior cell viability. In vivo analyses using the rabbit ear hypertrophic scar (HS) model indicated that the bilayer scaffold not only supported the reconstruction of new tissue, but also inhibited scar formation. The scaffold possibly achieved scar inhabitation by reducing wound contraction, weakening inflammatory reactions, and regulating collagen deposition and type conversion, which was partly observed through the downregulation of type I collagen, transforming growth factor-ß, and α-smooth muscle actin. This study describes a new strategy to expand the application of silk-based biomaterials for the treatment of hyperplastic skin scars.

Combined application of biochar and sulfur alleviates cadmium toxicity in rice by affecting root gene expression and iron plaque accumulation.

Biochar and sulfur are considered useful amendments for soil cadmium (Cd) contamination remediation. However, there is still a gap in the understanding of how combined biochar and sulfur application affects Cd resistance in rice, and the role of the accumulation of iron plaque and the expression of Cd efflux transporter-related genes are still unclear in this type of treatment. In this study, we screened an effective combination of biochar and sulfur (0.75 % biochar, 60 mg/kg sulfur) that significantly reduced the Cd content of rice roots (32.9 %) and shoots (12.3 %); significantly reduced the accumulation of amino acids and their derivatives, organic acids and their derivatives and flavonoids in rice roots; and altered secondary metabolite production and release. This combined biochar and sulfur application alleviated the toxicity of Cd to rice, in which the enhancement of iron plaque (24.8 %) formation and upregulated expression of heavy metal effector genes (NRAMP3, MTP3, ZIP1) were important factors. These findings show that iron plaque and heavy metal transport genes are involved in the detoxification of rice under the combined application of biochar and sulfur, which provides useful information for the combined treatment of soil Cd pollution.

Association between dietary carotenoids intake and chronic constipation in American men and women adults: a cross-sectional study.

BACKGROUND: Dietary carotenoids have been proven to improve intestinal disorders like inflammatory bowel disease and colon cancer, yet little is known about the link between dietary carotenoids and constipation. This study aims to examine the relationship between dietary carotenoids intake and constipation, using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2010. METHODS: A total of 11,722 participants were enrolled. Chronic constipation was defined as type 1 (separate hard lumps, like nuts) and type 2 (sausage-like, but lumpy) in the Bristol stool form scale (BSFS). Carotenoids intake was obtained from the average of two 24-hour dietary recall questionnaires (if only one 24-hour was available, we used it) and divided into quartiles (Q). The prevalence of constipation was calculated across men and women individuals. The relationship between dietary carotenoids intake and constipation in men and women was assessed with weighted logistic regression and smoothed curve fitting after adjusting confounders, with results displayed as weighted odds ratio (OR) with 95% confidence intervals (95% CI). The model was further stratified by age, race, and HEI 2015 scores (with median as cutoff) among men and women. RESULTS: The total weighted prevalence of chronic constipation in this study was 8.08%, 11.11% in women and 5.18% in men. After multivariable adjustment, compared with the lowest intake, participants with the highest dietary lycopene intake (ORQ4 vs. Q1= 0.55, 95% CI: 0.36-0.84, p for trend = 0.01) and total lycopene intake (ORQ4 vs. Q1 = 0.52, 95% CI: 0.34-0.80, p for trend = 0.01) were negatively associated with the risk of chronic constipation in men, whereas increased dietary α-carotene intake reduced the risk of chronic constipation in women (ORQ4 vs. Q1 = 0.69, 95% CI: 0.48-0.98, p for trend = 0.04). Smoothing curve fitting further supported these results and provided evidence of dose-response effects. No association was found between other types of carotenoids and chronic constipation in men and women. CONCLUSIONS: Increasing lycopene intake may improve bowel function in men while increased α-carotene intake may reduce the risk of chronic constipation in women. Further studies are essential to explore the role that the intake of carotenoids plays in chronic constipation.

Advanced Treatment of Coking Wastewater by Polyaluminum Silicate Sulfate for Organic Compounds Removal.

Coking wastewater is a typical high-strength organic wastewater, for which it is difficult to meet discharging standards with a single biological treatment. In this study, effective advanced treatment of coking wastewater was achieved by coagulation with freshly prepared polyaluminum silicate sulfate (PASS). The performance advantage was determined through comparison with commercial coagulants including ferric chloride, polyferric sulfate, aluminum sulfate and polyaluminum chloride. Both single-factor and Taguchi experiments were conducted to determine the optimal conditions for coagulation with CODCr and UV254 as indicators. A dosage of 7 mmol/L PASS, flocculation velocity of 75 r/min, flocculation time of 30 min, pH of 7, and temperature of 20 °C could decrease the CODCr concentration from 196.67 mg/L to 59.94 mg/L. Enhanced coagulation could further help to remove the organic compounds, including pre-oxidation with ozonation, adsorption with activated carbon, assistant coagulation with polyacrylamide and secondary coagulation. UV spectrum scanning and gas chromatography-mass spectrometry revealed that the coagulation process effectively removed the majority of organic compounds, especially the high molecular weight alkanes and heterocyclic compounds. Coagulation with PASS provides an effective alternative for the advanced treatment of coking wastewater.

Antibiotic Toxicity Isolated and as Binary Mixture to Freshwater Algae Raphidocelis subcapitata: Growth Inhibition, Prediction Model, and Environmental Risk Assessment.

Antibiotics in aqueous environments can have extremely adverse effects on non-targeted organisms. However, many research projects have only focused on the toxicological evaluation of individual antibiotics in various environments. In the present work, individual and binary mixture toxicity experiments have been conducted with the model organism Raphidocelis subcapitata (R. subcapitata), and a mixture concentration-response curve was established and contrasted with the estimated effects on the basis of both the concentration addition (CA) and the independent action (IA) models. In addition, different risk assessment methods were used and compared to evaluate the environmental risk of binary mixtures. The toxic ranking of the selected antibiotics to R. subcapitata was erythromycin (ERY) > sulfamethoxazole (SMX) > sulfamethazine (SMZ). In general, the conclusion of this study is that the adverse effects of binary mixtures are higher than the individual antibiotics. The CA model and RQSTU are more suitable for toxicity prediction and risk assessment of binary mixtures. This study reveals the potential ecological risks that antibiotics and their mixtures may pose to water ecosystems, thus providing scientific information for environmental quality regulation.

[Inhibitory effects of Bellamya aeruginosa on common algae in freshwater blooms]. / 铜锈环棱螺对水华中常见藻类的抑制效应.

The increasingly frequent algal blooms in freshwater have become a major environmental problem in the world. In recent years, algae removal by the biological method is receiving more attention for its eco-friendly characteristics. In this study, we examined the effects of Bellamya aeruginosa, a common macrobenthic snail in eutrophic lakes in China, on the growth and photosynthesis activities of the common algae occurred in freshwater blooms, including cyanobacterium Microcystis aeruginosa, coupled with green algae Chlorella vulgaris and Scenedesmus obliquus. The main aims were to clarify the interactive relationships between B. aeruginosa and algae, and to verify feasibility of using B. aeruginosa as an algal-removing organism. The results showed that B. aeruginosa could feed a large amount of algae cells in a short period after inoculation, and reached the maximal removal rate of toxic and non-toxic M. aeruginosa as well as S. obliquus within 12 hours, which were 73.7%, 73.2%, and 51.1%, respectively. Furthermore, its feeding on C. vulgaris was stronger than on other algae, with the removal rate reaching 99.2% by the end of the experiment. The microcystins produced by the toxic M. aeruginosa accumulated in the body of B. aeruginosa induced the histopathological changes in the liver tissue, and thereby hindered the feeding of B. aeruginosa. In the late stage of the experiment, the photosynthetic activities of the algal cells under each treatment were significantly lower than that in the control, indicating that the feeding of B. aeruginosa damaged algal cells and inhibited their proliferation. In addition, in the mixture of non-toxic M. aeruginosa and S. obliquus, the selective feeding of B. aeruginosa caused the dominance of non-toxic M. aeruginosa to be replaced by S. obliquus. Therefore, B. aeruginosa could inhibit the photosynthesis and reduce the biomass of algae through feeding, and thus would eliminate or mitigate the formation of algal blooms.

The carrier mobility of monolayer and bulk GaS: from first-principles calculations.

Metal chalcogenides have become popular materials for next-generation electronic devices due to their wide band gap and excellent transport properties. Specifically, two-dimensional metal chalcogenides also have outstanding physical properties. For electronic devices, the carrier mobility is a key parameter because it affects the material conductivity and the response time. As a member of metal chalcogenides, GaS has attracted the attention of scholars. In this work, by using first principles calculations and the Wannier function interpolation, the electronic and phonon properties, the electron-phonon interaction, the scattering rate, and the carrier mobility of monolayer and bulk GaS are systematically studied. The results show that GaS is a semiconductor and both monolayer and bulk GaS are dynamically stable. The LO phonon modes at long wavelengths strongly affect the carrier migration in GaS. We give the carrier mobility of monolayer and bulk GaS as a function of temperature (100 < K < 500). In addition, we compare the carrier mobility of GaS with several other metal chalcogenides (monolayer and bulk InSe, monolayer GeS, and monolayer GeSe) at 300 K. The results show that an increase in temperature leads to a decrease in the carrier mobility and the electron (hole) mobility of monolayer and bulk GaS is 10.85 cm2 V-1 s-1 (0.22 cm2 V-1 s-1) and 1229.79 cm2 V-1 s-1 (9.28 cm2 V-1 s-1), respectively. By comparing with the carrier mobility of other chalcogenides, we can find that the electron mobility of bulk GaS is the highest, which indicates that bulk GaS has high application potential.

The vibrational and hyperfine spectroscopy toward laser cooling 87Sr35Cl.

We theoretically investigate the possibility of laser cooling 87Sr35Cl molecule in accordance with vibrational and hyperfine spectroscopy. The potential energy curves and dipole moment of the X2Σ+1/2, A2Π1/2,3/2 and B2Σ+ states are calculated using ab initio method and the spectroscopic parameters are in good agreement with the experimental data. On account of the accurate potential energy curves and the transition dipole moment, the Franck - Condon factors and radiative lifetimes are predicted. Comparing the conditions of laser cooling candidate molecules, the A2Π 1/2 â†” X2Σ+1/2 transition is selected as the laser cooling cycle system. In order to obtain an approximately closed cooling cycle system, we employed matrix element algorithm to calculated the hyperfine spectroscopy and branching ratios of the 87Sr35Cl molecule. Furthermore, an electro-optical modulator (EOM) is designed including six hyperfine levels of the ground state X2Σ+1/2 (v = 0, N = 1).

Co-treatment of betulin and gefitinib is effective against EGFR wild-type/KRAS-mutant non-small cell lung cancer by inducing ferroptosis.

Clinical trials suggest that non-small-cell lung cancer (NSCLC) patients with KRAS mutations and wild-type EGFR have reduced benefits from gefitinib treatment. Ferroptosis is a new form of cell death that plays an important role in mediating the sensitivity of EGFR-TIKs. Here, we explored the antitumor ability of gefitinib in combination with betulin to overcome drug resistance through ferroptosis in wild-type EGFR/KRAS-mutant NSCLC cells. A549 and H460 cells were treated with gefitinib and betulin, and cell viability, apoptosis, and migration ability were assessed using the CCK-8 assay, flow cytometry, and wound-healing assay, respectively. Several cell death inhibitors were used to study the form of cell death. Ferroptosis-related events were detected by performing reactive oxygen species (ROS) and iron level detection, malondialdehyde (MDA) assay, and glutathione (GSH) assay. EMT-associated proteins and ferroptosis-related proteins were detected by using western blotting. A xenograft model was constructed in vivo to investigate the role of the combination treatment of betulin and gefitinib in NSCLC tumor growth. Gefitinib in combination with betulin exhibited antagonistic effects on cellular viability and induced cell apoptosis. It also induced ROS accumulation, lipid peroxidation, and GSH depletion and induced ferroptosis-related gene expression. Moreover, ferroptosis inhibitors, but not inhibitors of other forms of cell death, abrogated the effect of gefitinib in combination with betulin. Moreover, it also inhibited the tumor growth of NSCLC in vivo. Our findings suggest that gefitinib in combination with betulin is a novel therapeutic approach to overcome gefitinib resistance in EGFR wild-type/KRAS-mutant NSCLC cells by inducing ferroptosis.

The alteration of RhoA geranylgeranylation and Ras farnesylation breaks the integrity of the blood-testis barrier and results in hypospermatogenesis.

Non-obstructive azoospermia (NOA) severely affects male infertility, however, the deep mechanisms of this disease are rarely interpreted. In this study, we find that undifferentiated spermatogonial stem cells (SSCs) still exist in the basal compartment of the seminiferous tubules and the blood-testis barrier (BTB) formed by the interaction of neighbor Sertoli cells (SCs) is incomplete in NOA patients with spermatogenic maturation arrest. The adhesions between SCs and germ cells (GCs) are also broken in NOA patients. Meanwhile, the expression level of geranylgeranyl diphosphate synthase (Ggpps), a key enzyme in mevalonate metabolic pathway, is lower in NOA patients than that in obstructive azoospermia (OA) patients. After Ggpps deletion specifically in SCs, the mice are infertile and the phenotype of the SC-Ggpps-/- mice is similar to the NOA patients, where the BTB and the SC-GC adhesions are severely destroyed. Although SSCs are still found in the basal compartment of the seminiferous tubules, fewer mature spermatocyte and spermatid are found in SC-Ggpps-/- mice. Further examination suggests that the defect is mediated by the aberrant protein isoprenylation of RhoA and Ras family after Ggpps deletion. The exciting finding is that when the knockout mice are injected with berberine, the abnormal cell adhesions are ameliorated and spermatogenesis is partially restored. Our data suggest that the reconstruction of disrupted BTB is an effective treatment strategy for NOA patients with spermatogenic maturation arrest and hypospermatogenesis.

Human U3 protein14a is a novel type ubiquitin ligase that binds RB and promotes RB degradation depending on a leucine-rich region.

The nucleolar protein hUTP14a promotes p53 degradation and possesses an oncogene potential. Here, we report that hUTP14a promotes degradation of tumor suppressor retinoblastoma (RB) protein. Sequences alignment showed that hUTP14a contains the RB-binding PENF motif in its C-terminus. We showed that hUTP14a interacted with RB in vivo and in vitro. Further, hUTP14a promoted polyubiquitination and proteasome-dependent turnover of RB. Importantly, purified Flag-hUTP14a facilitated RB ubiquitination in vitro, demonstrating that hUTP14a is an ubiquitin E3 ligase for RB. A BLAST alignment with hUTP14a does not reveal a RING or HECT domain. To define the conserved domain for E3 ligase activity in hUTP14a, the minimum domain for promoting RB degradation was mapped to residues 61-120 of hUTP14a, in which a leucine-rich region (LRR) LxLxxLL was suggested to be conserved. Flag-hUTP14a (ΔLRR), Flag-hUTP14a-MT1(LxLxxLL to LxLxxAA) and Flag-hUTP14a-MT2(LxLxxLL to AxAxxAA) lost the capability of ubiquitinating RB in vitro, demonstrating that LRR is required for the E3 ligase activity of hUTP14a. Consequently, expression of hUTP14a caused upregulation of E2F1 downstream genes, thus promoting cancer cell proliferation. Taken together, we demonstrate that hUTP14a promotes RB degradation through its E3 ligase activity and suggest that the LRR could be a potential conserved E3 ligase domain.

Inflammatory serum proteins are severely altered in metastatic gastric adenocarcinoma patients from the Chinese population.

BACKGROUND: Inflammation is one of the major hallmarks of cancer. This study was designed to profile a panel of inflammatory mediators in gastric adenocarcinoma (GA) and to identify their potential differences separately in metastatic and non-metastatic patient subgroups. METHODS: Serum samples from 216 GA patients and 333 healthy controls from China were analyzed for six proteins using the Luminex multiplex assay. RESULTS: The serum levels for all the six proteins were significantly elevated in metastatic GA compared to non-metastatic GA. Two acute phase proteins (SAA and CRP) and a CXC chemokine (GRO) were significantly elevated in metastatic GA (p <0.01) but smaller changes were observed in non-metastatic GA compared to healthy controls. OPN is moderately increased in non-metastatic GA (2.05-fold) and more severely elevated in metastatic GA (3.34-fold). Surprisingly, soluble VCAM1 and AGP were significantly lower in both non-metastatic and metastatic GA patients compared to controls. Several individual proteins were shown to possess moderate diagnostic value for non-metastatic GA (AUC = 0.786, 0.833, 0.823 for OPN, sVCAM1 and AGP, respectively) and metastatic GA (AUC = 0.931, 0.720, 0.834 and 0.737 for OPN, sVCAM1, SAA and CRP, respectively). However, protein combinations further improve the diagnostic potential for both non-metastatic GA (best AUC = 0.946) and metastatic GA (best AUC = 0.963). The protein combination with best AUC value for both comparisons is OPN+sVCAM1+AGP+SAA. CONCLUSIONS: These results suggest that several serum proteins are directly related to the severity of gastric cancer. Overall, stronger associations are observed with metastatic than non-metastatic GA as the protein changes are greater with the metastatic status. A combination of these serum proteins may serve as non-invasive markers to assess the severity status and stage of gastric cancer.

Serum Dickkopf-1 (DKK1) is significantly lower in patients with lung cancer but is rapidly normalized after treatment.

DKK1 is a secreted glycoprotein that inhibits Wnt/ß-catenin signaling but may up-regulate the nonconanical Wnt signaling. Consistent with its inhibitory function in Wnt/ß-catenin signaling, aberrant DKK1 expression has been observed in many types of human cancers, while contradicting findings have been reported in other studies. There are also several studies on serum DKK1 levels in various cancers with conflicting findings. In the present study, serum DKK1 was determined in 217 non- small cell lung cancer (NSCLC) patients, 35 small cell lung cancer (SCLC) patients and 286 matched healthy controls using a commercially available ELISA assay kit. Compared to healthy controls, serum DKK1 level was significantly lower in NSCLC (p < 10(-28)) and SCLC (p <10(-4)) patients. Interestingly, serum DKK1 level was higher in NSCLC patients in stage IV (p < 0.0005), with lymph node involvement (p < 0.0002) or with metastasis (p < 0.0001), suggesting that DKK1 may promote metastasis. After surgery and/or chemotherapy, serum DKK1 level is rapidly increased and reached levels observed in healthy controls in most patients. The degree of post therapeutic DKK1 increase varied in different treatment regimens. Our results thus provide strong evidence for the reduced levels of serum DKK1 in both types of lung cancer. However, in the context of all published studies, DKK1 appears to have a dichotomous role in cancer and its effect in a given cancer type or even a given cancer patient is likely to depend on the molecular context of the patient.

Rapid, controllable fabrication of regular complex microarchitectures by capillary assembly of micropillars and their application in selectively trapping/releasing microparticles.

A simple strategy to realize new controllable 3D microstructures and a novel method to reversibly trapping and releasing microparticles are reported. This technique controls the height, shape, width, and arrangement of pillar arrays and realizes a series of special microstructures from 2-pillar-cell to 12 cell arrays, S-shape, chain-shape and triangle 3-cell arrays by a combined top down/bottom up method: laser interference lithography and capillary force-induced assembly. Due to the inherent features of this method, the whole time is less than 3 min and the fabricated area determined by the size of the laser beam can reach as much as 1 cm(2) , which shows this method is very simple, rapid, and high-throughput. It is further demonstrated that the 'mechanical hand'-like 4-cell arrays could be used to selectively trap/release microparticles with different sizes, e.g., 1.5, 2, or 3.5 µm, which are controlled by the period of the microstructures from 2.5 to 4 µm, and 6 µm. Finally, the 'mechanical hand'-like 4-cell arrays are integrated into 100 µm-width microfluidic channels prepared by ultraviolet photolithography, which shows that this technique is compatible with conventional microfabrication methods for on-chip applications.

Biomimetic growth of hydroxyapatite on phosphorylated electrospun cellulose nanofibers.

In biomimicking the formation of collagen fiber/hydroxyapatite (HAp) in natural bone, electrospun cellulose nanofiber (CelluNF)/HAp composites were synthesized in simulated body fluid (SBF). Their morphology and structure were characterized by SEM, TEM, XRD and XPS. CelluNFs showed low bioactivity in inducing the growth of HAp. In order to improve this ability, CelluNFs were slightly phosphorylated with a degree of substitution of phosphate group of 0.28. The modified CelluNFs were highly effective in guiding the HAp growth along the fibers. The HAp crystal size in the composites was ca. 24 nm, and the lattice spacing of (211) plane was 2.83 Å. It was found that the HAps in the composites were calcium deficient. The CelluNF/HAp composites are highly porous materials with micro-, meso-, and macro-pores. A mechanism for the HAp growth on CelluNFs was presented. Such CelluNF/HAp composites can be potentially useful in the field of bone tissue engineering.

Sodium dodecyl sulfate-induced rapid gelation of silk fibroin.

The in situ formation of injectable silk fibroin (SF) hydrogels have potential advantages over various other biomaterials due to the minimal invasiveness during application. Biomaterials need to gel rapidly under physiological conditions after injection. In the current paper, a novel way to accelerate SF gelation using an anionic surfactant, sodium dodecyl sulfate (SDS), as a gelling agent is reported. The mechanism of SDS-induced rapid gelation was determined. At low surfactant concentrations, hydrophobic interactions among the SF chains played a dominant role in the association, leading to decreased gelation time. At higher concentrations of surfactant, electrostatic repulsive forces among micellar aggregates gradually became dominant and gelation was hindered. Gel formation involves the connection of clusters formed by the accumulation of nanoparticles. This process is accompanied by the rapid formation of ß-sheet structures due to hydrophobic and electrostatic interactions. It is expected that the silk hydrogel with short gelation time will be used as an injectable hydrogel in drug delivery or cartilage tissue engineering.

A small ribosomal subunit (SSU) processome component, the human U3 protein 14A (hUTP14A) binds p53 and promotes p53 degradation.

Ribosome biogenesis is required for normal cell function, and aberrant ribosome biogenesis can lead to p53 activation. However, how p53 is activated by defects of ribosome biogenesis remains to be determined. Here, we identified human UTP14a as an SSU processome component by showing that hUTP14a is nucleolar, associated with U3 snoRNA and involved in 18 S rRNA processing. Interestingly, ectopic expression of hUTP14a resulted in a decrease and knockdown of hUTP14a led to an increase of p53 protein levels. We showed that hUTP14a physically interacts with p53 and functionally promotes p53 turn-over, and that hUTP14a promotion of p53 destabilization is sensitive to a proteasome inhibitor but independent of ubiquitination. Significantly, knockdown of hUTP14a led to cell cycle arrest and apoptosis. Our data identified a novel pathway for p53 activation through a defect in rRNA processing and suggest that a ribosome biogenesis factor itself could act as a sensor for nucleolar stress to regulate p53.