Physical therapy for acute and sub-acute low back pain: A systematic review and expert consensus

OBJECTIVE

To review the effectiveness of different physical therapies for acute and sub-acute low back pain supported by evidence, and create clinical recommendations and expert consensus for physiotherapists on clinical prescriptions.

DATA SOURCES

A systematic search was conducted in PubMed and the Cochrane Library for studies published within the previous 15 years.

REVIEW METHODS

Systematic review and meta-analysis, randomized controlled trials assessing patients with acute and sub-acute low back pain were included. Two reviewers independently screened relevant studies using the same inclusion criteria. The Physiotherapy Evidence Database and the Assessment of Multiple Systematic Reviews tool were used to grade the quality assessment of randomized controlled trials and systematic reviews, respectively. The final recommendation grades were based on the consensus discussion results of the Delphi of 22 international experts.

RESULTS

Twenty-one systematic reviews and 21 randomized controlled trials were included. Spinal manipulative therapy and low-level laser therapy are recommended for acute low back pain. Core stability exercise/motor control, spinal manipulative therapy, and massage can be used to treat sub-acute low back pain.

CONCLUSIONS

The consensus statements provided medical staff with appliable recommendations of physical therapy for acute and sub-acute low back pain. This consensus statement will require regular updates after 5-10 years.

[Effects and techniques of soft tissue augmentation in immediate implant treatment]

Immediate implant placement can reduce the number of treatments and the time without teeth, but it carries a higher aesthetic risk. Soft tissue augmentation can reduce the risk of gingival recession to a certain extent, improve the predictability and long-term stability of immediate implant aesthetics, and is currently a hot research topic. A comprehensive understanding of the evidence-based medicine and surgical techniques using soft tissue augmentation in immediate implant surgery can assist in clinical diagnosis, treatment decisions and improve treatment outcomes. This article elucidates the changes in soft and hard tissues after immediate implant placement, aesthetic risks, and risk factors. It also discusses the advantages, timing, material selection, and commonly used clinical techniques of soft tissue transplantation in immediate implantation, aiming to provide reference for clinical doctors to improve the effectiveness of immediate implantation.

Determination of Spin-Parity Quantum Numbers of X(2370) as 0^{-+} from J/ψ→γK_{S}^{0}K_{S}^{0}η^{'}

Based on (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst)  MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst)  MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.

Etching of Ag nanoparticles triggered bidirectional regulation for electrochemiluminescence ratiometric immunoassay

A highly efficient ratiometric electrochemiluminescence (ECL) immunoassay was explored by bidirectionally regulating the ECL intensity of two luminophors. The immunoassay was conducted in a split-type mode consisting of an ECL detection procedure and a sandwich immunoreaction. The ECL detection was executed using a dual-disk glassy carbon electrode modified with two potential-resolved luminophors (g-C3N4-Ag and Ru-MOF-Ag nanocomposites), and the sandwich immunoreaction using glucose oxidase (GOx)-modified SiO2 nanospheres as labels was carried out in a 96-well plate. The Ag nanoparticles (NPs) acted as bifunctional units both for triggering the resonance energy transfer (RET) with g-C3N4 and for accelerating the electron transfer rate of the Ru-MOF-Ag ECL reaction. When the H2O2 catalyzed by GOx in the 96-well plate was transferred to the dual-disk glass carbon electrode, the doped Ag NPs in the two luminophors could be etched, thus destroying the RET between C3N4 and the accelerated reaction to Ru-MOF, resulting in an opposite trend in the ECL signal outputted from the dual disks. Using the ratio of the two signals for quantification, the constructed immunosensor for a model target, i.e. myoglobin, exhibited a low detection limit of 4.7 × 10-14 g/mL. The ingenious combination of ECL ratiometry, bifunctional Ag NPs, and a split-type strategy effectively reduces environmental and human errors, offering a more precise and sensitive analysis for complex samples.

Establishment and application of an indirect ELISA for Getah virus E2 antibody detection

Getah virus (GETV) is a mosquito-transmitted disease that affects animals, causing fever, aseptic meningitis, and abortion. Its prevalence in China poses risks to both animal health and public well-being. Currently, there is a scarcity of seroepidemiological data on GETV due to the absence of commercial antibody detection kits for pigs. The aim of this study is to develop a rapid, accurate, and sensitive ELISA, providing a reliable tool for GETV seroepidemiology and laying the foundation for future commercial assay development. In this study, we removed specific hydrophobic domains and intracellular structures from E2 proteins and constructed the recombinant plasmid pCold-TF-E2. The recombinant protein was expressed using a prokaryotic expression system, and efficient purification of the rE2 protein was achieved using a nickel affinity column. The purified rE2 protein is suitable for the development of an indirect ELISA (rE2 ELISA). Following the optimization of reaction conditions for the rE2-ELISA, the cut-off value was 0.356. Additionally, the rE2-ELISA method showed a positive rate of 37.1% for IgG antibodies against GETV when testing 986 pig clinical serum samples collected from pigs in Sichuan between May 2022 and September 2022. The rE2-ELISA method displayed a 95.1% overall agreement with VNT, boasting a sensitivity of 98.2% and a specificity of 92.6%. These results indicate that IgG ELISA based on rE2 protein is an efficient and economical method for the detection of GETV antibodies in pigs, facilitating the diagnosis and prevention of GETV.

Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93  fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.

Observation of Significant Flavor-SU(3) Breaking in the Kaon Wave Function at 12<Q^{2}<25 GeV^{2} and Discovery of the Charmless Decay ψ(3770)→K_{S}^{0}K_{L}^{0}

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5  fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12 Collapse

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Pargyline-phosphine copper(I) clusters with tunable emission for light-emitting devices

Three pargyline-phosphine copper(I) clusters, [Cu4(CC-C9H12N)3(PPh3)4](PF6) (1) and [Cu6(CC-C9H12N)4(dppy)4](X)2 (dppy = diphenyl-2-pyridylphosphine; X = PF6 for 2 and X = ClO4 for 3), were synthesized. Their structures were fully characterized using various spectroscopic methods and X-ray crystallography, which showed that the stoichiometry and nature of pargyline and phosphine ligands play an important role in tuning the structure and photophysical features of Cu(I) clusters. Interestingly, clusters 1, 2 and 3 exhibited red, orange and yellow phosphorescence with high quantum yields of 88.5%, 22.0% and 40.2%, respectively, at room temperature. Moreover, clusters 1-3 show distinct temperature-dependent emissions. The excellent luminescence performance of 1 and 3 was designed and employed for the construction of monochrome and white light-emitting devices (LEDs).

Metal-Organic Frameworks Possessing Suitable Pores for Xe/Kr Separation

Adsorption separation of the Xe/Kr mixture remains a tough issue since Xe and Kr have an inert nature and similar sizes. Here we present a chlorinated metal-organic framework (MOF) [JXNU-19(Cl)] and its nonchlorinated analogue (JXNU-19) for Xe/Kr separation. The two isostructural MOFs constructed from the heptanuclear cobalt-hydroxyl clusters bridged by organic ligands are three-dimensional structures. Detailed contrast of the Xe/Kr adsorption separation properties of the MOF shows that significantly enhanced Xe uptakes and Xe/Kr adsorption selectivity (17.1) are observed for JXNU-19 as compared to JXNU-19(Cl). The main binding sites for Xe in the MOF revealed by computational simulations are far away from the chlorine sites, suggesting that the introduction of the chlorine groups results in the unfavorable Xe adsorption for JXNU-19(Cl). The optimal pores, high surface area, and multiple strong Xe-framework interactions facilitate the effective Xe/Kr separation for JXNU-19.

In Situ Growth Reaction on Photoelectrodes of Single-Atom Fe Incorporated Bi4O5I2: A General Photoelectrochemical Immunoassay Toward Sensitive Protein Analysis

As one of the interesting signaling mechanisms, the in situ growth reaction on a photoelectrode has proven its powerful potential in photoelectrochemical (PEC) bioanalysis. However, the specific interaction between the signaling species with the photoactive materials limits the general application of the signal mechanism. Herein, on the basis of an in situ growth reaction on a photoelectrode of single-atom-based photoactive material, a general PEC immunoassay was developed in a split-type mode consisting of the immunoreaction and PEC detection procedure. Specifically, a single-atom photoactive material that incorporates Fe atoms into layered Bi4O5I2 (Bi4O5I2-Fe SAs) was used as a photoelectrode for PEC detection. The sandwich immunoreaction was performed in a well of a 96-well plate using Ag nanoparticles (Ag NPs) as signal tracers. In the PEC detection procedure, the Ag+ converted from Ag NPs were transferred onto the surface of the Bi4O5I2-Fe SAs photoelectrode and thereafter AgI was generated on the Bi4O5I2-Fe SAs in situ to form a heterojunction through the reaction of Ag+ with Bi4O5I2-Fe SAs. The formation of heterojunction greatly promoted the electro-hole separation, boosting the photocurrent response. Exemplified by myoglobin (Myo) as the analyte, the immunosensor achieved a wide linear range from 1.0 × 10-11 to 5.0 × 10-8 g mL-1 with a detection limit of 3.5 × 10-12 g mL-1. This strategy provides a general PEC immunoassay for disease-related proteins, as well as extends the application scope of in situ growth reaction in PEC analysis.

[Relationship between sleep status and occasional hypertension in preschool children in three provinces in the middle and lower reaches of the Yangtze River in China]

Objective: To understand the prevalence of occasional hypertension in preschool children in three provinces in the middle and lower reaches of the Yangtze River in China, and analyze the relationship between their sleep status and occasional hypertension. Methods: From October to November 2017, a total of 24 842 preschool children from 109 kindergartens in 11 cities in Hubei, Anhui and Jiangsu provinces were selected by intentional sampling method. A self-made questionnaire was used to collect basic information about the subjects, and the sleep status data was collected by the Children's Sleep Habits Questionnaire. Physical examinations were performed on the subjects, and height, weight and blood pressure were measured on-site. The difference in occasional hypertension detection rate among preschool children with different characteristics was compared, and the correlation between sleep status and occasional hypertension detection rate was analyzed by the multivariate logistic regression model. Results: The age of the subjects was (4.4±1.0) years, including 12 729 boys (51.2%). The prevalence of occasional hypertension was 31.8% (7 907/24 842). The prevalence of occasional hypertension among preschool children in three provinces of the middle and lower reaches of the Yangtze River was 31.8%. There were statistically significant differences in the detection rate of occasional hypertension among preschool children of different genders, age groups, family residence, family economic status and parents' education level (all P values<0.05). The detection rate of occasional hypertension in children with less than 10 hours of sleep was higher than those with sufficient sleep, and the difference was statistically significant (P<0.05). The results of multivariate logistic regression analysis showed that after adjusting for factors such as gender, age, family residence, family economic status, parental education level, parental smoking history, and physical constitution, the ORs (95%CI) for less than 10 hours of sleep, turning on the lights while sleeping, and poor sleep quality were 1.09 (1.03-1.15), 1.17 (1.07-1.28) and 1.04 (0.91-1.18), respectively, compared with the corresponding reference group. Conclusion: The detection rate of occasional hypertension is high in preschool children in the middle and lower reaches of the Yangtze River and there is a positive correlation between insufficient sleep and turning on the light when sleeping and occasional hypertension in preschool children.

[Research advances on application of sub-epidermal moisture scanner in monitoring tissue viability of early pressure injuries]

Pressure injury (PI) not only reduces the quality of life of patients but also is expensive to manage, placing a heavy financial burden on patients and their families, and society. Despite the increasing diversity of methods used to identify early PI, there are still few methods that can truly and accurately predict early PI. The sub-epidermal moisture scanner is the first U.S. Food and Drug Administration-authorized PI management device that can predict the occurrence and development of PI by measuring the level of local tissue bio-capacitance and monitoring the tissue viability. As an emerging diagnostic instrument, the sub-epidermal moisture scanner has already shown great advantages in clinical practice, which can promote the informatization, digitization, and intelligent prevention and management of PI. This paper introduces the pathophysiological mechanism of PI, elucidates the working principle and parameter settings of the sub-epidermal moisture scanner, its clinical application in monitoring tissue viability in early PI, and its limitation, and looks forward to its future development.

[Prioritizing the integrated management of cancer pain to comprehensively enhance the diagnosis and treatment proficiency in cancer pain]

As one of the most common complications of cancer or its treatment, cancer-related pain can negatively affect the functional status and quality of life of patients. Pain management for cancer patients in China started later than that in developed countries. After 30 years of efforts by health authorities and medical professionals, cancer pain management in China has made great progress. However, with the accelerated aging of the Chinese population, the increasing incidence of cancer, the prolonged survival of cancer patients, and the strengthening of people's expectations for high-quality life, there is still a gap between the development level of cancer pain management in China and the actual health needs of cancer patients. This article provides a comprehensive overview of the current state and future challenges facing the integrated management of cancer pain in China. Simultaneously, it offers a prospective outlook on future developments, thereby furnishing vital information for professionals engaged in the field of cancer pain management.

Hyperoside attenuates carbon tetrachloride-induced hepatic fibrosis via the poly(ADP-ribose)polymerase-1-high mobility group protein 1 pathway

Oxidative stress and inflammation have been implicated in hepatic fibrosis. Antioxidant and anti-inflammatory activities are among the pharmacological effects of hyperoside. This study aimed to evaluate the impact of hyperoside on hepatic fibrosis and elucidate the underlying processes that perpetuate this relationship. The findings indicated that hyperoside significantly protects mouse livers against damage, inflammation, and fibrosis. Specifically, attenuation of hepatic fibrosis is associated with lower expression of HMGB1 protein and reduced expression of Toll-like receptor 4, PARP-1, and nuclear factor-kB (NF-κB) p65 mRNA and protein. Furthermore, hyperoside inhibited the cytoplasmic translocation of HMGB1 and nuclear localization of NF-κB p65 in the hepatic tissues of mice. The results of this study indicate that hyperoside may impose a blocking or reversing effect on hepatic fibrosis; additionally, the corresponding hyperoside-dependent mechanism may be linked to PARP-1-HMGB1 pathway regulation.

The States of Different 5-HT Receptors Located in the Dorsal Raphe Nucleus Are Crucial for Regulating the Awakening During General Anesthesia

General anesthesia is widely used in various clinical practices due to its ability to cause loss of consciousness. However, the exact mechanism of anesthesia-induced unconsciousness remains unclear. It is generally thought that arousal-related brain nuclei are involved. 5-Hydroxytryptamine (5-HT) is closely associated with sleep arousal. Here, we explore the role of the 5-HT system in anesthetic awakening through pharmacological interventions and optogenetic techniques. Our data showed that exogenous administration of 5-hydroxytryptophan (5-HTP) and optogenetic activation of 5-HT neurons in the dorsal raphe nucleus (DR) could significantly shorten the emergence time of sevoflurane anesthesia in mice, suggesting that regulation of the 5-HT system using both endogenous and exogenous approaches could mediate delayed emergence. In addition, we first discovered that the different 5-HT receptors located in the DR, known as 5-HT autoreceptors, are essential for the regulation of general anesthetic awakening, with 5-HT1A and 5-HT2A/C receptors playing a regulatory role. These results can provide a reliable theoretical basis as well as potential targets for clinical intervention to prevent delayed emergence and some postoperative risks.

[Clinical phenotype and genetic analysis of patients with left ventricular noncompaction caused by the biallelic mutation of MYBPC3 and MYH7]

Objective: To explore the relationship between pathogenic gene, mutation and phenotype of left ventricular noncompaction (LVNC) patients and their family members. Methods: The subjects were the proband with LVNC and her family members. The medical history including electrocardiogram, echocardiography and cardiac magnetic resonance examination of the proband and family members were collected. Whole exome sequencing of the proband was performed, bioinformatics analysis focused on the genes related to hereditary cardiomyopathy. Candidate pathogenic sites were validated by Sanger sequencing. The clinical interpretation of sequence variants were classified according to American College of Medical Genetics and Genomics (ACMG) guidelines. Results: The proband carried a heterozygous variation of the MYBPC3 gene c.C2827T and the MYH7 gene c.G2221C. The proband's sister carried heterozygous variation of MYBPC3 gene c.C2827T. According to the ACMG guidelines, the variant was determined to be pathogenic. Conclusion: The missense variant of MYBPC3 gene c.C2827T and MYH7 gene c.G2221C are identified from the proband with LVNC and her family member, which provides a genetic basis for clinical diagnosis and genetic counseling of the patients and the family members with LVNC.

[A rational analysis of the commonly used renal tumor scoring systems in predicting surgical outcomes of cystic renal masses]

Objective: To explore the predictive effect of the renal tumor scoring system on the surgical outcomes of cystic renal masses (CRM). Methods: A retrospective analysis was performed on the data of 234 patients who received robotic-assisted partial nephrectomy (RAPN) treatment in the First Affiliated Hospital of Xi'an Jiaotong University from January 2018 to June 2020. And 31 cases had CRM and 203 cases had solid renal masses (SRM). The propensity score of patients was calculated by logistic regression model, and 1∶2 matching was performed by the nearest neighbor method. The changes in perioperative indexes and long-term estimated glomerular filtration rate (eGFR) in CRM group and SRM group were compared. The CRM group and SRM group were stratified according to the complexity grading of R.E.N.A.L. score and PADUA score, respectively, to compare the difference in the achievement rate of ideal surgical outcome between the two groups, and analyze the predictive factors affected. The CRM diameter was stratified with 4 cm as the cut-off value (CRM1 group with a diameter<4 cm, CRM2 group with a diameter≥4 cm), and the surgical results were compared with the matched SRM1 group and SRM2 group. Results: In the matching cohort, the CRM group comprised 29 patients with a mean age of (48.7±10.8) years, of which 22 (75.9%) were males. The SRM group included 58 patients with a mean age of (50.4±10.2) years, of which 41 (70.7%) were males, with no statistically significant difference (all P>0.05). The warm ischemia time (WIT) [M (Q1,Q3)] in the CRM group was longer than that in the SRM group [23(18, 25) vs 19(17, 25) min, P=0.040]. The operation time (OT) [M (Q1,Q3)] in the CRM group was also longer than that of the SRM group [130(100, 150) vs 108(86, 120) min, P=0.006]. The change in serum creatinine before and after the operation [M (Q1,Q3)] was higher in the CRM group than in the SRM group [15(10, 23) vs 12(6, 17) μmol/L, P=0.030]. The ideal surgical outcomes were achieved in 7 patients (24.1%) in the CRM group and 36 patients (62.1%) in the SRM group. The number of patients achieving ideal surgical outcomes in R.E.N.A.L. intermediate complex surgery and PADUA advanced complex surgery in the SRM group were 24 (58.5%) and 15 (51.7%), respectively, which were higher than those in the CRM group 6 (27.3%) and 1 (5.9%) respectively (P<0.05). Preoperative eGFR (OR=0.758, 95%CI: 0.719-0.799) and the nature of the tumor (CRM as reference, OR=4.883, 95%CI: 1.550-15.378) were influencing factors for achieving the ideal surgical outcome. Subgroup analysis showed that eGFR changes before and after surgery and the estimated blood loss (EBL) in the CRM2 group were higher than those in the SRM2 group, and WIT and OT were longer than those in the SRM2 group (all P<0.05). The EBL and WIT of the CRM1 group were shorter than those of the CRM2 group (P<0.05). Conclusion: The surgical risk of RAPN in complex CRMs with a maximum diameter of≥4 cm is higher than the risk of RAPN in SRM with equivalent R.E.N.A.L. and PADUA scores.

Signature of spin-phonon coupling driven charge density wave in a kagome magnet

The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.

RAP80 Phase Separation at DNA Double-Strand Break Promotes BRCA1 Recruitment and Tumor Radio-Resistance

PURPOSE/OBJECTIVE(S)

RAP80 has been characterized as a component of the BRCA1-A complex and is responsible for the recruitment of BRCA1 to DNA double-strand breaks (DSBs). However, we and others found that the recruitment of RAP80 and BRCA1 are not absolutely temporally synchronized, indicating that other mechanisms, apart from physical interaction, may be implicated. Recently, we and other groups have reported that liquid-liquid phase separation (LLPS) is a pivotal mechanism underlying DNA repair factors condensation at DSBs and their function. In this study, we aim to disclose whether RAP80 undergoes LLPS at DSBs and whether it is required for BRCA1 recruitment.

MATERIALS/METHODS

To verify RAP80 is an LLPS protein and its function in DNA damage response (DDR): (1) candidate-mEGFP fusion protein formed condensates in cells and showed fluorescence recovery after photobleaching (FRAP); (2) candidate protein was expressed in Escherichia coli and purified with GST; (3) intrinsically disordered region (IDR) of RAP80 were predicted and tested in cell and in vitro; (4) lentivirus were used to construct RAP80-Knock out (KO) and RAP80 re-expression cell lines; (5) length gradient K63 poly-ubiquitin chains were chemically synthesized and incubated with RAP80 protein in vitro; (6) BRCA1 and RAP80 location were determined through immunofluorescence; (7) RAP80 protein expression in tissue was determined by IHC staining.

RESULTS

Thin layer scanning and 3D reconstruction of the RAP80-mEGFP-expressing cells under a fluorescence microscope showed that RAP80-mEGFP formed spherical condensates with fast FRAP. Observation of purified proteins revealed that GST-RAP80-mEGFP protein formed liquid-like droplets, presenting as a FRAP and the fusion event among adjacent droplets. PEG-8000 and Ficol-400 strengthened the formation of GST-RAP80-mEGFP droplets in vitro. Later, we used a previously developed optoIDR tool to verify that IDR1 (1-254aa) is critical for RAP80 LLPS. To investigate whether the interaction between RAP80 and K63 poly-ubiquitin chains could enhance the condensation of RAP80, we chemically synthesized K63 ubiquitin chains and incubated them with purified GST-RAP80-mCherry proteins. The results showed that supplementation of ubiquitin multipolymer (poly-ubiquitin) significantly induced the LLPS of RAP80, and the ability of RAP80 condensates formation potency was positively correlated with the length of the ubiquitin chain. Consistent with their LLPS capacity, RAP80-WT-mEGFP, RAP80-(IDR1+AIR)-mEGFP groups showed prominent BRCA1 foci, while RAP80-IDR1-mEGFP and RAP80-(SIM+UIM)-mEGFP groups showed delayed BRCA1 recruitment. In rectal cancer tissues, positive staining of the RAP80 protein was mainly observed in the nucleus of cancer cells and high RAP80 expression was correlated with a shorter overall survival time.

CONCLUSION

RAP80 undergoes LLPS to form liquid-like condensates at DSB sites, which is important for BRCA1 recruitment and enhances tumor radio-resistance.

Ubiquitinated H2A.X-Induced RNF168 Condensation Promotes DNA Double-Strand Break Repair and Tumor Radioresistance

PURPOSE/OBJECTIVE(S)

Ubiquitination of histone is an essential process involved in DNA damage response (DSB) serving as scaffolds for DNA repair proteins, but how these factors are recruited so quickly and regulated in a spatiotemporal manner remains poorly understood. Liquid-liquid phase separation (LLPS) has recently emerged as a mechanism for membraneless condensation driven by multivalent interactions. In this study, we aimed to investigate the LLPS potential of RNF168, an E3 ligase essential for DSB repair, and the mechanism underlying its-mediated tumor radio-resistance.

MATERIALS/METHODS

The intrinsic disordered domain (IDR) of RNF168 was determined by the PONDR website. The LLPS properties were validated by droplet formation in vivo and in vitro. RNF168-mEGFP were expressed in Escherichia coli and purified with GST tag. The synthesized K63-linked ubiquitin chains were added to mimic the interactions between RNF168 and radiation-induced ubiquitinated-histone. Effects of RNF168 LLPS on downstream proteins were verified by immunofluorescence.

RESULTS

RNF168-mEGFP recombinant protein formed liquid-like droplets in vivo and co-localized with γ-H2A.X foci after irradiation. The droplet's fluorescence recovered quickly after photobleaching, which could be abolished by 1,6-hexanediol treatment or ATP deprivation. Purified RNF168-mEGFP protein also condensed in vitro, and the size and number of droplets were related to protein concentration, salt concentration, pH, and temperature. Condensation of RNF168 was dependent on the IDR (323-459 amino acid), and more importantly, enhanced by synthesized K63-linked ubiquitin chains. LLPS of RNF168 was required for recruitment of RNF168 to DSB and RNF168-mediated γ-H2A.X ubiquitination. LLPS deficiency of RNF168 resulted in decreased recruitment of 53BP1, BRCA1, and RAP80 proteins, resulting in impaired DSB repair and genomic instability. Notably, higher expression of RNF168 was correlated with a poorer response to neoadjuvant radiochemotherapy in rectal cancer patients. Finally, RNF168 condensate-induced tumor radioresistance was further verified in the xenograft model.

CONCLUSION

RNF168 undergoes LLPS at the DSB site, which is determined by both the IDR domain and the interaction with K63-linked ubiquitin chains. Radiation-induced RNF168 condensation accelerates the accumulation of RNF168 and promotes the recruitment of downstream effectors to DSB, resulting in enhanced DSB repair and tumor radioresistance.

Priority list of potential endocrine-disrupting chemicals in food chemical contaminants: a docking study and in vitro/epidemiological evidence integration

Diet is an important exposure route of endocrine-disrupting chemicals (EDCs), but many unfiltered potential EDCs remain in food. The in silico prediction of EDCs is a popular method for preliminary screening. Potential EDCs in food were screened using Endocrine Disruptome, an open-source platform for inverse docking, to predict the binding probabilities of 587 food chemical contaminants with 18 human nuclear hormone receptor (NHR) conformations. In total, 25 contaminants were bound to multiple NHRs such as oestrogen receptor α/β and androgen receptor. These 25 compounds mainly include pesticides and per- and polyfluoroalkyl substances (PFASs). The prediction results were validated with the in vitro data. The structural features and the crucial amino acid residues of the four NHRs were also validated based on previous literature. The findings indicate that the screening has good prediction efficiency. In addition, the epidemic evidence about endocrine interference of PFASs in food on children was further validated through this screening. This study provides preliminary screening results for EDCs in food and a priority list for in vitro and in vivo research.

Ionic Liquids-Driven Cluster-to-Cluster Conversion of Polyhydrido Copper(I) Clusters Cu7H5 to Cu8H6 and Cu12H9

Although ionic liquids (ILs) are of prime interest for the synthesis of various nanomaterials, they are scarcely utilized for the polyhydrido copper(I) [Cu(I)H] clusters. Herein, two air-stable Cu(I)H clusters, [Cu8H6(dppy)6](NTf2)2 (Cu8H6) and {Cu12H9(dppy)6[N(CN)2]3} (Cu12H9), are synthesized in high yields for the first time from the ILs-driven conversion of an unprecedented cluster [Cu7H5(dppy)6](ClO4)2 (Cu7H5) by a facile three-layers diffusion crystal (TLDC) method, strategically introducing IL-NTf2 and IL-N(CN)2 as two types of unusual interfacial crystallized templates, respectively. Their structures are fully characterized by various spectroscopic methods and X-ray crystallography, which shows that the anion of IL plays an important role as an anion template and an anion ligand in controlling the structural conversion of Cu(I)H clusters. Their photophysical properties are also investigated, and it is found that all reported clusters exhibit red luminescence with λem ranging from 600 to 690 nm.

Cucurbituril-Shaped Cd18(triazolate)12 Unit-Based Metal-Organic Framework Exhibiting an C2H2/CO2 Separation Ability

Herein, a metal-organic framework (MOF), {[(Me2NH2)4][Cd(H2O)6][Cd18(TrZ)12(TPD)15(DMF)6]}n (denoted as JXNU-18, TrZ = triazolate), constructed from the unique cucurbituril-shaped Cd18(TrZ)12 secondary building units bridged by 2,5-thiophenedicarboxylic (TPD2-) ligands, is presented. The formation of the cucurbituril-shaped Cd18(TrZ)12 unit is unprecedented, demonstrating the geometric compatibility of the organic linkers and the coordination configurations of the cadmium atoms. Each Cd18(TrZ)12 unit is connected to eight neighboring Cd18(TrZ)12 units through 30 TPD2- linkers, affording the three-dimensional structure of JXNU-18. More interesting is that JXNU-18 displays an efficient C2H2/CO2 separation ability, as revealed by the gas adsorption experiments and dynamic gas breakthrough experiments, which afford insights into the potential applications of JXNU-18 in gas separation. The tubular pores composed of two Cd18(TrZ)12 units bridged by six 2,5-thiophenedicarboxylic linkers provide the suitable pore space for C2H2 trapping, as unveiled by computational simulations.