Pairing with Enriched Sound Exposure Restores Auditory Processing Degraded by an Antidepressant.

Antidepressants, while effective in treating depression and anxiety disorders, also induce deficits in sensory (particularly auditory) processing, which in turn may exacerbate psychiatric symptoms. How antidepressants cause auditory signature deficits remains largely unknown. Here, we found that fluoxetine-treated adult female rats were significantly less accurate when performing a tone-frequency discrimination task compared with age-matched control rats. Their cortical neurons also responded less selectively to sound frequencies. The degraded behavioral and cortical processing was accompanied by decreased cortical perineuronal nets, particularly those wrapped around parvalbumin-expressing inhibitory interneurons. Furthermore, fluoxetine induced critical period-like plasticity in their already mature auditory cortices; therefore, a brief rearing of these drug-treated rats under an enriched acoustic environment renormalized auditory processing degraded by fluoxetine. The altered cortical expression of perineuronal nets was also reversed as a result of enriched sound exposure. These findings suggest that the adverse effects of antidepressants on auditory processing, possibly because of a reduction in intracortical inhibition, can be substantially alleviated by simply pairing drug treatment with passive, enriched sound exposure. They have important implications for understanding the neurobiological basis of antidepressant effects on hearing and for designing novel pharmacological treatment strategies for psychiatric disorders.SIGNIFICANCE STATEMENT Clinical experience suggests that antidepressants adversely affect sensory (particularly auditory) processing, which can exacerbate patients' psychiatric symptoms. Here, we show that the antidepressant fluoxetine reduces cortical inhibition in adult rats, leading to degraded behavioral and cortical spectral processing of sound. Importantly, fluoxetine induces a critical period-like state of plasticity in the mature cortex; therefore, a brief rearing under an enriched acoustic environment is sufficient to reverse the changes in auditory processing caused by the administration of fluoxetine. These results provide a putative neurobiological basis for the effects of antidepressants on hearing and indicate that antidepressant treatment combined with enriched sensory experiences could optimize clinical outcomes.

Colossal Ferroelectric Photovoltaic Effect in Inequivalent Double-Perovskite Bi2FeMnO6 Thin Films.

Double perovskite films have been extensively studied for ferroelectric order, ferromagnetic order, and photovoltaic effects. The customized ion combinations and ordered ionic arrangements provide unique opportunities for bandgap engineering. Here, a synergistic strategy to induce chemical strain and charge compensation through inequivalent element substitution is proposed. A-site substitution of the barium ion is used to modify the chemical valence and defect density of the two B-site elements in Bi2FeMnO6 double perovskite epitaxial thin films. We dramatically increased the ferroelectric photovoltaic effect to ∼135.67 µA/cm2 from 30.62 µA/cm2, which is the highest in ferroelectric thin films with a thickness of less than 100 nm under white-light LED irradiation. More importantly, the ferroelectric polarization can effectively improve the photovoltaic efficiency of more than 5 times. High-resolution HAADF-STEM, synchrotron-based X-ray diffraction and absorption spectroscopy, and DFT calculations collectively demonstrate that inequivalent ion plays a dual role of chemical strain (+1.92 and -1.04 GPa) and charge balance, thereby introducing lattice distortion effects. The reduction of the oxygen vacancy density and the competing Jahn-Teller distortion of the oxygen octahedron are the main phenomena of the change in electron-orbital hybridization, which also leads to enhanced ferroelectric polarization values and optical absorption. The inequivalent strategy can be extended to other double perovskite systems and applied to other functional materials, such as photocatalysis for efficient defect control.

Interbrain substrates of role switching during mother-child interaction.

Mother-child interaction is highly dynamic and reciprocal. Switching roles in these back-and-forth interactions serves as a crucial feature of reciprocal behaviors while the underlying neural entrainment is still not well-studied. Here, we designed a role-controlled cooperative task with dual EEG recording to explore how differently two brains interact when mothers and children hold different roles. When children were actors and mothers were observers, mother-child interbrain synchrony emerged primarily within the theta oscillations and the frontal lobe, which highly correlated with children's attachment to their mothers (self-reported by mothers). When their roles were reversed, this synchrony was shifted to the alpha oscillations and the central area and associated with mothers' perception of their relationship with their children. The results suggested an observer-actor neural alignment within the actor's oscillations, which was related to the actor-toward-observer emotional bonding. Our findings contribute to the understanding of how interbrain synchrony is established and dynamically changed during mother-child reciprocal interaction.

Transcription factors MdMYC2 and MdMYB85 interact with ester aroma synthesis gene MdAAT1 in apple.

Volatile esters in apple (Malus domestica) fruit are the critical aroma components determining apple flavor quality. While the exact molecular regulatory mechanism remains unknown, jasmonic acid (JA) plays a crucial role in stimulating the synthesis of ester aromas in apples. In our study, we investigated the effects of methyl jasmonate (MeJA) on the production of ester aroma in apples. MeJA treatment significantly increased ester aroma synthesis, accompanied by the upregulation of several genes involved in the jasmonate pathway transduction. Specifically, expression of the gene MdMYC2, which encodes a transcription factor associated with the jasmonate pathway, and the R2R3-MYB transcription factor gene MdMYB85 increased upon MeJA treatment. Furthermore, the essential gene ALCOHOL ACYLTRANSFERASE 1 (MdAAT1), encoding an enzyme responsible for ester aroma synthesis, showed increased expression levels as well. Our investigation revealed that MdMYC2 and MdMYB85 directly interacted with the promoter region of MdAAT1, thereby enhancing its transcriptional activity. In addition, MdMYC2 and MdMYB85 directly bind their promoters and activate transcription. Notably, the interaction between MdMYC2 and MdMYB85 proteins further amplified the regulatory effect of MdMYB85 on MdMYC2 and MdAAT1, as well as that of MdMYC2 on MdMYB85 and MdAAT1. Collectively, our findings elucidate the role of the gene module consisting of MdMYC2, MdMYB85, and MdAAT1 in mediating the effects of JA and promoting ester aroma synthesis in apples.

Proteomic profiling of prostate cancer reveals molecular signatures under antiandrogen treatment.

BACKGROUND: Tumorigenesis and progression of prostate cancer (PCa) are indispensably dependent on androgen receptor (AR). Antiandrogen treatment is the principal preference for patients with advanced PCa. However, the molecular characteristics of PCa with antiandrogen intervention have not yet been fully uncovered. METHODS: We first performed proteome analysis with 32 PCa tumor samples and 10 adjacent tissues using data-independent acquisition (DIA)- parallel accumulation serial fragmentation (PASEF) proteomics. Then label-free quantification (LFQ) mass spectrometry was employed to analyze protein profiles in LNCaP and PC3 cells. RESULTS: M-type creatine kinase CKM and cartilage oligomeric matrix protein COMP were demonstrated to have the potential to be diagnostic biomarkers for PCa at both mRNA and protein levels. Several E3 ubiquitin ligases and deubiquitinating enzymes (DUBs) were significantly altered in PCa and PCa cells under enzalutamide treatment, and these proteins might reprogram proteostasis at protein levels in PCa. Finally, we discovered 127 significantly varied proteins in PCa samples with antiandrogen therapy and further uncovered 4 proteins in LNCaP cells upon enzalutamide treatment. CONCLUSIONS: Our research reveals new potential diagnostic biomarkers for prostate cancer and might help resensitize resistance to antiandrogen therapy.

PoIL8-L, a teleost interleukin-8 like, enhances leukocyte cellular vitality and host defense against bacterial infections in Japanese flounder (Paralichthys olivaceus).

Interleukin-8 (IL-8), a CXC chemokine, exerts pivotal effect on cell migration, inflammatory response, and immune regulation. In this study, we examined the immunological characteristics of an IL-8 like homologue (PoIL8-L) in Japanese flounder (Paralichthys olivaceus). PoIL8-L contains a conserved chemokine CXC domain and 105 amino acid residues. PoIL8-L expression in tissues was constitutive, and significantly regulated by V. havieri or E. tarda infection. In vitro, rPoIL8-L could bind to eight tested bacteria, exhibited bacteriostatic and bactericidal effects against certain bacteria, and could bind to the targeted bacterial Ⅳ pilin protein rPilA of E. tarda. Furthermore, rPoIL8-L could attach to peripheral blood leukocytes, and enhance their immune genes expression, respiratory burst, chemotaxis, proliferation, acid phosphatase activity, and phagocytic activity. Additionally, rPoIL8-L induce neutrophils to extrude neutrophil extracellular traps. In vivo, rPoIL8-L could promote host resistance to E. tarda infection. In summary, these findings provide fresh perspectives on the immunological antibacterial properties of IL-8 in teleost.

Douglas Pouch Fluid Improves the Accuracy of Transvaginal Ultrasound in the Diagnosis of Uterosacral Ligaments Deep Infiltration Endometriosis: A Prospective Study.

OBJECTIVES: To compare the accuracy of transvaginal ultrasound (TVUS) with laparoscopy in detecting and characterizing uterosacral ligament (USL) nodules of deep infiltrative endometriosis (DIE) between patients with and without pouch of Douglas (POD) fluid. METHODS: This prospective study was conducted between June 2021 and July 2023. We included patients from the Second People's Hospital of Shenzhen with two TVUS tests: no POD fluid on the first TVUS test and POD fluid on the second TVUS test. POD fluid was obtained in two ways: naturally occurring fluid during the luteal phase of the menstrual cycle and SonoPODography. Laparoscopic results are the gold standard. To compare the diagnostic performance of TVUS in the diagnosis of DIE on USLs with and without POD fluid. RESULTS: We included 42 patients with a mean age of 36.4 ± 5.4 years. The maximum length diameter for DIE nodules on USLs with and without POD fluid was 13.3 ± 3.3 mm and 10.2 ± 2.5 mm (P < .001), respectively, while the depth of infiltration was 8.1 ± 2.4 mm and 6.1 ± 1.4 mm (P < .001), respectively. When compared to laparoscopic findings, TVUS findings with and without POD fluid resulted in a sensitivity, specificity, accuracy, positive predictive value, negative predictive value area under the curve, and Cohen kappa of 92.3%, 93.8%, 92.9%, 96.0%, 88.2%, 0.930, and 0.850 and 61.5%, 93.8%, 73.8%, 94.1%, 50.0%, 0.766, and 0.499, respectively. Laparoscopy showed USL involvement in up to 59.5% of patients. With or without fluid, the most common ultrasound features of DIE lesions were USL thickening, irregular morphology, clear boundaries, low echo, and no blood flow signal. CONCLUSIONS: For patients with clinical suspicion of DIE, TVUS with POD fluid has a higher accuracy for diagnosing USL DIE than TVUS without POD fluid.

Lower abdominal cyst complicated with suspected infection following INFIX internal fixation for pelvic fracture: a report of two rare cases.

BACKGROUND: The Internal Fixator (INFIX) is a popular method, known for its minimal invasiveness and short operation time, for treating anterior pelvic ring fractures. Studies have shown that postoperative complications may occur, including anterolateral femoral cutaneous nerve injury, the femoral nerve paralysis, and delayed fracture healing. These complications are believed to be related to surgical stimulation, an excessively long lateral end of the connecting rod, a small distance between the screw and bone surface, insufficient pre-bending of the connecting rod, and difficulties in fracture reduction. CASE PRESENTATION: We report two unique cases of lower abdominal pseudocyst complicated with suspected infection after INFIX treatment of pelvic fractures at our trauma center. Following surgical removal of the internal fixation, resolution of the cysts was observed in both patients, and subsequent postoperative follow-up revealed the absence of any residual sequelae. These cases have not been reported in previous literature reviews. DISCUSSION: The lower abdominal cysts, potentially arising from the dead space created during intraoperative placement of the INFIX rod, may increase infection risk. The etiology remains uncertain, despite the presence of abnormal inflammation markers in both cases, and staphylococcus aureus found in one. These cysts were confined to the lower abdomen, not involving the internal fixation, and hence, only the INFIX was removed. Postoperative oral cefazolin treatment was successful, with resolved pseudocysts and no subsequent discomfort. CONCLUSION: We report two unprecedented cases of post-INFIX abdominal cysts, with a suspected link to intraoperative dead space. Despite uncertain etiology, successful management involved INFIX removal and oral cefixime therapy. These findings necessitate further exploration into the causes and management of such complications.

Analysis of Distribution of Intracranial and Extracranial Atherosclerotic Lesions and Risk Factors for Recurrence in First-Ever and Recurrent Ischemic Stroke Patients in Northeast China.

Objective: The purpose of this study is to analyze the distribution characteristics of atherosclerotic lesions and the risk factors of recurrence in patients with ischemic stroke. Methods: A total of 505 patients diagnosed with ischemic stroke from October 2016 to October 2022 were included. Divide 505 patients with ischemic stroke into old stroke group and new stroke group. Patients without old cerebral infarction were included in the first ischemic stroke group (first group), while patients with old cerebral infarction were included in the recurrent ischemic stroke group (recurrence group).Carotid artery color Doppler ultrasonography and transcranial Doppler ultrasonography were performed on all patients. Results: We compared the distribution and risk factors of atherosclerotic lesions between the first and recurrent groups (378 cases) (127 cases). Mild, moderate, and severe stenosis of the middle cerebral artery (MCA) and occlusion of the intracranial vertebral artery (VA) were the most common in both groups. Intracranial artery stenosis is significantly higher than extracranial artery stenosis, and the anterior circulation artery is more affected than the posterior circulation artery. In the initial and recurrent groups, the proportion of patients with intracranial artery stenosis was significantly higher than that of patients with extracranial artery stenosis (43.4% vs. 22.5% and 53.4% vs. 22.5%), and the number of patients with anterior circulation stenosis was higher than that of other groups. Compared with the first group, the recurrence group had a higher incidence of hypertension, dyslipidemia, and insufficient physical exercise. There is a significant difference in the levels of triglycerides (TG) and platelets (PLT) between the two groups in biochemical indicators. In the first group, infarction was most common in 284 cases (75.1%) of the frontal lobe, followed by 232 cases (61.4%) of the basal ganglia, and 147 cases (38.9%) of the parietal lobe. In the recurrence group, the proportion of frontal lobe infarction [284 (74.0%)], basal ganglia infarction [232 (70.1%)], and parietal lobe infarction [147 (37.0%)] was the highest. It can be observed that the recurrence group had a higher incidence of basal ganglia infarction (70.1% vs. 61.4%), but a lower incidence of occipital lobe infarction (0.8% vs. 4.2%). Conclusions: Our study found no significant difference in the distribution of intracranial and extracranial atherosclerotic lesions between first-ever and recurrent ischemic stroke patients in China. Notably, hypertension, years of dyslipidemia, insufficient physical exercise, elevated triglyceride (TG) levels, and increased platelet (PLT) counts were identified as significant risk factors for stroke recurrence. These findings may have implications for the management and prevention of recurrent ischemic strokes in clinical practice.

Measuring Human Auditory Evoked Fields with a Flexible Multi-Channel OPM-Based MEG System.

BACKGROUND: Magnetoencephalography (MEG) is a non-invasive imaging technique for directly measuring the external magnetic field generated from synchronously activated pyramidal neurons in the brain. The optically pumped magnetometer (OPM) is known for its less expensive, non-cryogenic, movable and user-friendly custom-design provides the potential for a change in functional neuroimaging based on MEG. METHODS: An array of OPMs covering the opposite sides of a subject's head is placed inside a magnetically shielded room (MSR) and responses evoked from the auditory cortices are measured. RESULTS: High signal-to-noise ratio auditory evoked response fields (AEFs) were detected by a wearable OPM-MEG system in a MSR, for which a flexible helmet was specially designed to minimize the sensor-to-head distance, along with a set of bi-planar coils developed for background field and gradient nulling. Neuronal current sources activated in AEF experiments were localized and the auditory cortices showed the highest activities. Performance of the hybrid optically pumped magnetometer-magnetoencephalography/electroencephalography (OPM-MEG/EEG) system was also assessed. CONCLUSIONS: The multi-channel OPM-MEG system performs well in a custom built MSR equipped with bi-planar coils and detects human AEFs with a flexible helmet. Moreover, the similarities and differences of auditory evoked potentials (AEPs) and AEFs are discussed, while the operation of OPM-MEG sensors in conjunction with EEG electrodes provides an encouraging combination for the exploration of hybrid OPM-MEG/EEG systems.

Traumatic bilateral acetabular fracture secondary to high-energy trauma in healthy adults.

BACKGROUND: Bilateral acetabular fracture is a very rare presentation among the trauma patients, as the pattern and the degree of the forces required to fracture both acetabula is very unique. The primary purpose of this study is to report a series of adult patients presenting with post-traumatic bilateral acetabular fracture without any history of pathological or metabolic bone disease. PATIENTS AND METHODS: In this retrospective study, 18 cases of traumatic bilateral acetabular fracture were included. There was predominance of both column (four patients on left and six on right) followed by anterior column (two patients left and four on right) and posterior wall (three patients left and right). They were treated surgically through open reduction and internal fixation. All cases were followed up for at least 13 months. Matta's criteria were used for radiological evaluation on plain radiographs. Functional outcome was evaluated using the Merle d'Aubigne and postel score at final follow-up. RESULTS: No patients were lost during the follow-up period; there was one case of surgical site infection. There were three cases of postoperative osteoarthritis, one case of heterotrophic ossification, one case of persistent sciatic nerve palsy and one case of lateral femoral cutaneous nerve palsy. The radiological evaluation according to Matta's criteria revealed anatomic reduction in 12 patients, imperfect reduction in three patients while other three patients had poor reduction. According to modified Merle d'Aubigne and Postel score, 10 cases were rated as excellent, five cases as good and three cases presented fair (one case) to poor (two cases) results. CONCLUSION: We report an unusual case series of bilateral acetabular fracture successfully managed surgically with good clinical outcome. With the increasing incidence of route traffic accidents, such cases would probably be recurrent in the upcoming years.

A Machine Learning Model for Predicting the Propagation Rate Coefficient in Free-Radical Polymerization.

The propagation rate coefficient (kp) is one of the most crucial kinetic parameters in free-radical polymerization (FRP) as it directly governs the rate of polymerization and the resulting molecular weight distribution. The kp in FRP can typically be obtained through experimental measurements or quantum chemical calculations, both of which can be time consuming and resource intensive. Herein, we developed a machine learning model based solely on the structural features of monomers involved in FRP, utilizing molecular embedding and a Lasso regression algorithm to predict kp more efficiently and accurately. The result shows that the model achieves a mean absolute percentage error (MAPE) of only 5.49% in the predictions for four new monomers, which indicates that the model exhibits strong generalization capabilities and provides reliable and robust predictions. In addition, this model can accurately predict the influence of the ester side chain length of (meth)acrylates on kp, aligning well with established scientific knowledge. This approach offers a straightforward and practical model for other researchers to rapidly obtain accurate kp values by employing monomer structural information. The model is sufficiently general to apply to a wide range of (meth)acrylate and butadiene FRP monomers, thereby supporting kinetic modeling of polymerization reactions.

Combination therapy with hydrogen peroxide and irradiation promotes an abscopal effect in mouse models.

Hydrogen peroxide (H2 O2 ) induces oxidative stress and cytotoxicity, and can be used for treating cancers in combination with radiotherapy. A product comprising H2 O2 and sodium hyaluronate has been developed as a radiosensitizer. However, the effects of H2 O2 on antitumor immunity remain unclear. To investigate the effects of H2 O2 , especially the abscopal effect when combined with radiotherapy (RT), we implanted murine tumor cells simultaneously in two locations in mouse models: the hind limb and back. H2 O2 mixed with sodium hyaluronate was injected intratumorally, followed by irradiation only at the hind limb lesion. No treatment was administered to the back lesion. The H2 O2 /RT combination significantly reduced tumor growth at the noninjected/nonirradiated site in the back lesion, whereas H2 O2 or RT individually did not reduce tumor growth. Flow cytometric analyses of the tumor-draining lymph nodes in the injected/irradiated areas showed that the number of dendritic cells increased significantly with maturation in the H2 O2 /RT combination group. In addition, analyses of tumor-infiltrating lymphocytes showed that the number of CD8+ (cluster of differentiation 8) T cells and the frequency of IFN-γ+ (interferon gamma) CD8+ T cells were higher in the noninjected/nonirradiated tumors in the H2 O2 /RT group compared to those in the other groups. PD-1 (programmed death receptor 1) blockade further increased the antitumor effect against noninjected/nonirradiated tumors in the H2 O2 /RT group. Intratumoral injection of H2 O2 combined with RT therefore induces an abscopal effect by activating antitumor immunity, which can be further enhanced by PD-1 blockade. These findings promote the development of H2 O2 /RT therapy combined with cancer immunotherapies, even for advanced cancers.

Elevated O3 concentrations alter the compartment-specific microbial communities inhabiting rust-infected poplars.

Elevated ozone (O3 ) can affect the susceptivity of plants to rust pathogens. However, the collective role of microbiomes involved in such interaction remains largely elusive. We exposed two cultivated poplar clones exhibiting differential O3 sensitivities, to non-filtered ambient air (NF), NF + 40 ppb or NF + 60 ppb O3 -enriched air in field open-top chambers and then inoculated Melampsora larici-populina urediniospores to study their response to rust infection and to investigate how microbiomes inhabiting four compartments (phyllosphere, rhizosphere, root endosphere, bulk soil) are involved in this response. We found that hosts with higher O3 sensitivity had significantly lower rust severity than hosts with lower sensitivity. Furthermore, the effect of increased O3 on the diversity and composition of microbial communities was highly dependent on poplar compartments, with the microbial network complexity patterns being completely opposite between the two clones. Notably, microbial source analysis estimated that phyllosphere fungal communities predominately derived from root endosphere and vice versa, suggesting a potential transmission mechanism between plant above- and below-ground systems. These promising results suggest that further investigations are needed to better understand the interactions of abiotic and biotic stresses on plant performance and the role of the microbiome in driving these changes.

POR overexpression induces tamoxifen-resistance in breast cancer through the STAT1/c-Myc pathway.

Breast cancer is the most common cancer in women worldwide. Although tamoxifen (TAM), a selective estrogen receptor (ER) modulator, is widely used to treat ER-positive breast cancers, resistance to TAM remains a major clinical problem. NADPH-dependent cytochrome P450 reductase (POR) is known to participate in drug metabolism and steroid metabolism. Recent studies showed that high POR expression was correlated with poor outcomes in triple-negative breast cancer (TNBC), and POR might be a prognostic biomarker in TNBC. However, the role of POR in TAM resistance is still elusive. In this study, we found that high POR expression was associated with poor prognosis of ER-positive and TAM-treated breast cancer patients. In addition, COX analysis showed that POR expression was an independent prognostic biomarker for ER-positive as well as TAM-treated breast cancer patients. Furthermore, our results suggested that POR overexpression promoted TAM resistance by activating the STAT1/c-Myc pathway in ER-positive breast cancer cells. Immunohistochemical analysis showed that high POR/STAT1 expression was correlated with poor prognosis in TAM-treated breast cancer patients. Notably, combined treatment with TAM and a specific STAT1 inhibitor Fludarabine was more effective for inhibiting TAM-resistant breast cancer cells. Altogether, our findings suggested that POR overexpression induced TAM resistance through STAT1/c-Myc pathway and might serve as an independent prognostic biomarker in TAM-treated breast cancer patients. Combining TAM and STAT1 inhibitors might be an effective strategy for treating POR-induced TAM-resistant breast cancer.

Effects of Particulate Matter on the Risk of Gestational Hypertensive Disorders and Their Progression.

Associations between particulate matter (PM) and gestational hypertensive disorders (GHDs) are well documented, but there is no evidence on the associations between PM and GHD progression, especially among those with assisted reproductive technology (ART) conceptions. To explore the effects of PM on the risk of GHDs and their progression among pregnant women with natural or ART conception, we enrolled 185,140 pregnant women during 2014-2020 in Shanghai and estimated the associations during different periods using multivariate logistic regression. During the 3 months of preconception, 10 µg/m3 increases in PM concentrations were associated with increased risks of gestational hypertension (GH) (PM2.5: aOR = 1.076, 95% CI: 1.034-1.120; PM10: aOR = 1.042, 95% CI: 1.006-1.079) and preeclampsia (PM2.5: aOR = 1.064, 95% CI: 1.008-1.122; PM10: aOR = 1.048, 95% CI: 1.006-1.092 ) among women with natural conception. Furthermore, for women with ART conceptions who suffered current GHD, 10 µg/m3 increases in PM concentrations in the third trimester elevated the risk of progression (PM2.5: aOR = 1.156, 95% CI: 1.022-1.306 ; PM10: aOR = 1.134, 95% CI: 1.013-1.270). In summary, women with natural conception should avoid preconceptional PM exposure to protect themselves from GH and preeclampsia. For women with ART conceptions suffering from GHD, it is necessary to avoid PM exposure in late pregnancy to prevent the disease from progressing.

Molecular dynamics simulation of the impact of the surface topology of carbon black on the mechanical properties of elastomer nanocomposites.

Carbon black has always played a pivotal role in reinforcing elastomers because it remarkably improves the mechanical properties. The reinforcing effect of carbon black is influenced by its grades, which mainly depend on the difference in the structure of the carbon black particles. Despite many traditional experiments on the performance of carbon black composites, there has been less emphasis on reinforcement mechanisms due to the challenges associated with unraveling the intermolecular interactions. In this paper, a coarse grained molecular dynamics simulation was employed to examine the relationship between the morphology of the carbon black particles and the mechanical properties of the elastomer nanocomposites. Specifically, three different morphological carbon black nanoparticle models, including the smooth particle model, rough particle model, and the rough ellipsoid model, were constructed first. We then focused on investigating the changes of the mechanical properties by systematically varying the filling fraction of the carbon black particles, and the strength of the interfacial interaction between the filler and the rubber. The results indicated that the surface roughness and the filler's shape had a significant impact on the mechanical properties of the filled rubber models. The mechanical enhancement effect of the rough ellipsoidal carbon black is around 50-400% higher than that of the smooth carbon black, and the stronger the interfacial interactions, the more pronounced the enhancement. In addition, the rough ellipsoid filled system has low hysteresis, low permanent deformation, and high fatigue resistance. In general, this work explores the strengthening mechanism of carbon black on the elastomer at the molecular level and generates new insight into the design and fabrication of novel reinforcing fillers.

A systematic review of instruments measuring the quality of dying and death in Asian countries.

PURPOSE: This study aimed to systematically identify, appraise, and summarize the psychometric properties of instruments used to measure the quality of dying and death in Asian countries. METHODS: The Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) was closely followed. The literature was searched using the following keywords and their synonyms: "death and dying," "measurement," and "Asian country" in CINAHL, PubMed, PsycInfo, Web of Science, and Cochrane Library from inception to April 2021. Two reviewers independently screened titles and abstracts and reviewed the full text. Two other reviewers independently assessed the quality of the identified studies in three steps: methodological quality evaluation, good measurement properties evaluation, and quality of evidence evaluation. RESULTS: This review retrieved 37,195 studies, of which seven were finally included. Four instruments that assessed the quality of dying and death in Asian countries were identified: the Good Death Inventory (GDI), the Good Death Scale (GDS), and two versions of the Quality of Dying and Death (QODD) Questionnaires. All included studies failed to evaluate all the recommended psychometric properties, and none of the instruments provided strong evidence of their quality among Asian populations. Overall, the grade of evidence quality for the GDI was moderate, the highest among all identified instruments. CONCLUSION: The GDI is by far the most reliable instrument for assessing the quality of dying and death in Asian populations. A lack of validation studies in Asian and Western cultures, however, warrants caution when drawing conclusions from the GDI.

Femoral neck fractures in non-geriatric patients: femoral neck system versus cannulated cancellous screw.

BACKGROUND: The fractures of femoral neck account for 50% among hip fractures with around 3%-10% occurring in younger population of below 65 years. The newly introduced FNS as management approach appears to be a potential alternative to the traditional CCS. The aim of this study was to compare the clinical efficacy and outcome of the femoral neck system (FNS) and the cannulated cancellous screw (CCS) in the treatment of femoral neck fractures in adult below 65 years of age. METHODS: Data of 114 patients between 18-65 years, admitted in our department for femoral neck fracture from January 2019 to March 2021 were retrospectively studied and ranged into two groups based on the surgical methods: FNS group (56 patients) and CCS group (58 patients). The variables of interest including demographic and clinical variables (age, gender, fracture mechanism, injury side and classification), perioperative parameters(operation time, intraoperative bleeding, incision length and hospitalization time), postoperative outcomes and complications (fracture healing time, nonunion rate, femoral neck avascular necrosis, aseptic screw loosening and the Harris Hip Score), were analyzed and compared between the two groups. RESULTS: All 114 patients presented satisfactory reduction and were followed-up for a period of 12 to 36 months (mean 27 ± 2.07 months); there were no significant differences between both groups in terms of age, gender, fracture classification, side of injury, mechanism of injury, the operative time, intraoperative blood loss and the hospital length of stay. However, the fracture healing time between FNS group and CCS group was statistically significant (p < 0.05), respectively 2.86 ± 0.77 and 5.10 ± 0.81 months. The significant differences were also found in terms of numbers of fluoroscopies 8.34 ± 1.38 Vs 17.72 ± 2.19, the HHS 87.80 ± 1.92 Vs 84.28 ± 2.24, postoperative complications 8 (14.28%) Vs 26 (44.82) respectively in FNS and CCS group. CONCLUSION: FNS presented satisfactory outcomes had significantly lower complications rate, therefore, can be one of the alternatives for internal implantation devices in treatment of femoral neck fracture in non-geriatric population.

Medium-term clinical results in patients with floating hip injuries.

BACKGROUND: The objective of this study was to evaluate the effectiveness of our strategy for managing floating hip injuries. METHODS: From January 2014 and December 2019, all patients with a floating hip underwent surgical treatment in our hospital were included in the retrospective study, with a minimum follow-up of 1 year. All patients were managed according to a standardised strategy. Data on epidemiology, radiography, clinical outcomes and complications were collected and analysed. RESULTS: Twenty-eight patients were enrolled, with an average age of 45 years. The mean follow-up was 36.9 months. According to the Liebergall classification, Type A floating hip injuries predominated (n = 15, 53.6%). Head and chest injuries were the most common associated injuries. When multiple operative settings were required, we prioritized the fixation of the femur fracture at the first operation. The mean time from injury to definitive femoral surgery was 6.1 days, with most (75%) femoral fractures treated with intramedullary fixation. More than half (54%) of acetabular fractures were treated with a single surgical approach. Pelvic ring fixation included isolated anterior fixation, isolated posterior fixation, combined anterior and posterior fixation, of which isolated anterior fixation was the most common. Postoperative radiographs suggested that the anatomic reduction rates of acetabulum and pelvic ring fractures were 54% and 70%, respectively. According to grading system of Merle d'Aubigne and Postel, 62% of patients achieved satisfactory hip function. Complications included delayed incision healing (7.1%), deep vein thrombosis (10.7%), heterotopic ossification (10.7%), femoral head avascular necrosis (7.1%), post-traumatic osteoarthritis (14.3%), fracture malunion (n = 2, 7.1%) and nonunion (n = 2, 7.1%). In the patients with complications described above, only two patients underwent resurgery. CONCLUSIONS: Although there is no difference in clinical outcomes and complications among different types of floating hip injuries, special attention should be paid to anatomical reduction of the acetabular surface and restoration of the pelvic ring. In addition, the severity of such compound injuries often exceeds that of an isolated injury and often requires specialised multidisciplinary management. Because of no standard guidelines for treatment of such injuries, our experience in the management of such a complex case is to fully assess the complexity of the injury and formulate an appropriate surgical plan based on the principles of damage control orthopaedics.