Oligoasthenoteratospermia and sperm tail bending in PPP4C-deficient mice

Protein phosphatase 4 (PPP4) is a protein phosphatase that, although highly expressed in the testis, currently has an unclear physiological role in this tissue. Here, we show that deletion of PPP4 catalytic subunit gene Ppp4c in the mouse causes male-specific infertility. Loss of PPP4C, when assessed by light microscopy, did not obviously affect many aspects of the morphology of spermatogenesis, including acrosome formation, nuclear condensation and elongation, mitochondrial sheaths arrangement and '9 + 2' flagellar structure assembly. However, the PPP4C mutant had sperm tail bending defects (head-bent-back), low sperm count, poor sperm motility and had cytoplasmic remnants attached to the middle piece of the tail. The cytoplasmic remnants were further investigated by transmission electron microscopy to reveal that a defect in cytoplasm removal appeared to play a significant role in the observed spermiogenesis failure and resulting male infertility. A lack of PPP4 during spermatogenesis causes defects that are reminiscent of oligoasthenoteratospermia (OAT), which is a common cause of male infertility in humans. Like the lack of functional PPP4 in the mouse model, OAT is characterized by abnormal sperm morphology, low sperm count and poor sperm motility. Although the causes of OAT are probably heterogeneous, including mutation of various genes and environmentally induced defects, the detailed molecular mechanism(s) has remained unclear. Our discovery that the PPP4C-deficient mouse model shares features with human OAT might offer a useful model for further studies of this currently poorly understood disorder.

Adventitial remodeling protects against aortic rupture following late smooth muscle-specific disruption of TGFβ signaling

Altered signaling through transforming growth factor-beta (TGFβ) increases the risk of aortic dissection in patients, which has been confirmed in mouse models. It is well known that altered TGFβ signaling affects matrix turnover, but there has not been a careful examination of associated changes in structure-function relations. In this paper, we present new findings on the rupture potential of the aortic wall following late postnatal smooth muscle cell (SMC)-specific disruption of type I and II TGFβ receptors in a mouse model with demonstrated dissection susceptibility. Using a combination of custom computer-controlled biaxial tests and quantitative histology and immunohistochemistry, we found that loss of TGFβ signaling in SMCs compromises medial properties but induces compensatory changes in the adventitia that preserve wall strength above that which is needed to resist in vivo values of wall stress. These findings emphasize the different structural defects that lead to aortic dissection and rupture - compromised medial integrity and insufficient adventitial strength, respectively. Relative differences in these two defects, in an individual subject at a particular time, likely reflects the considerable phenotypic diversity that is common in clinical presentations of thoracic aortic dissection and rupture. There is, therefore, a need to move beyond examinations of bulk biological assays and wall properties to cell- and layer-specific studies that delineate pathologic and compensatory changes in wall biology and composition, and thus the structural integrity of the aortic wall that can dictate differences between life and death.

The Association between Tea Consumption and the Risk of Fracture: A Dose-Response Meta-Analysis of Prospective Cohort Studies

OBJECTIVES

Inconsistent results exist on the role of tea consumption on subsequent risk of fracture. A dose-response meta-analysis was therefore conducted to assess the association of tea consumption with the risk of fracture based on prospective cohort studies.

METHODS

The electronic databases of PubMed, Embase, and the Cochrane library were systematically searched to identify prospective cohort studies from inception until September 2020. The categories of high versus low and dose-response meta-analyses for tea consumption on the risk of fracture were calculated using the random-effects model. Eight prospective cohort studies recruited 774,134 individuals selected for the final meta-analysis.

RESULTS

An increment of 1 cup in tea consumption was not associated with the risk of fracture [relative risk (RR), 0.98; 95% confidence interval (CI), 0.96-1.00; P = 0.102]. Moreover, the highest tea consumption category was associated with a reduced risk of fracture (RR, 0.93; 95% CI, 0.88-0.98; P = 0.005). Furthermore, heavy (RR, 0.91; 95% CI, 0.85-0.98; P = 0.008) and mild (RR, 0.97; 95% CI, 0.94-1.00; P = 0.046) tea consumption were associated with lower risk of fracture. However, moderate tea consumption was not associated with the risk of fracture (RR, 0.98; 95% CI, 0.94-1.02; P = 0.281).

CONCLUSION

This study found that increased tea consumption may provide a protective role in the risk of fracture. The benefits of tea consumption should be further explored according to the characteristics of the individuals.

Endovascular Recanalization of Symptomatic Nonacute Intracranial Internal Carotid Artery Occlusion: Proposal of a New Angiographic Classification

BACKGROUND AND PURPOSE

The optimal treatment for symptomatic nonacute intracranial ICA occlusion is uncertain, and endovascular recanalization remains a technical challenge. Our purpose was to report multicenter clinical results of endovascular recanalization for medically refractory, nonacute, intracranial ICA occlusion and to propose a new angiographic classification to explore which subgroups of patients are most amenable to this treatment.

MATERIALS AND METHODS

From January 2015 to December 2019, thirty-six consecutive patients who underwent endovascular recanalization for refractory, nonacute, atherosclerotic intracranial ICA occlusion at 3 stroke centers were analyzed retrospectively. The patients were divided into 3 types according to an angiographic classification. Rates of technical success, periprocedural complications, and any stroke or death within 30 days along with follow-up results were evaluated.

RESULTS

The overall technical success rate was 80.6% (29/36), and the rate of any stroke or death within 30 days was 16.7% (6/36). The recanalization success rate gradually decreased from type I to type III in the 3 classification groups (92.9%, 81.3%, and 50%, P = .038), and the opposite was true of the perioperative complication rates (7.1%, 18.8%, and 50%, P = .038). Type I lesions showed favorable recanalization effects, 92.9% technical success rates, and 7.1% perioperative complications.

CONCLUSIONS

Endovascular recanalization for nonacute atherosclerotic intracranial ICA occlusion is technically feasible, especially in patients with type I lesions, and could offer an alternative option for patients with recurrent ischemic symptoms despite aggressive medical therapy. The angiographic classification proposed is conducive to the selection of suitable patients and difficulty in grading.

The combined impact of xylo-oligosaccharides and gamma-irradiated Astragalus polysaccharides on growth performance and intestinal mucosal barrier function of broilers

This study was conducted to investigate the individual and combined effects of xylo-oligosaccharides (XOS) and gamma-irradiated Astragalus polysaccharides (IAPS) on the growth performance and intestinal mucosal barrier function of broiler chickens. A total of 240 1-day-old Ross-308 chicks were allocated into 5 groups for 21 d: control group (basal diet), antibiotic growth promoter (AGP) group (basal diet supplemented with 50 mg/kg chlortetracycline), XOS group (basal diet supplemented with 100 mg/kg XOS), IAPS group (basal diet supplemented with 600 mg/kg IAPS), and XOS + IAPS group (basal diet supplemented with 100 mg/kg XOS and 600 mg/kg IAPS). The results showed that birds in the XOS + IAPS group showed higher ADG and lower feed-to-gain ratio than those in the control group (P < 0.05). The XOS, IAPS, and XOS + IASP treatments significantly increased villus height (VH) of all intestine segments, jejunal goblet cell numbers, and VH–to–crypt depth ratio (VH/CD) of broilers than those of the control group (P < 0.05). Birds in the XOS + IAPS group had higher jejunal VH/CD ratio and goblet cell numbers than those from the XOS or IAPS groups (P < 0.05). In addition, there was a synergy effect between XOS and IAPS on increasing duodenal goblet cell numbers and improving ileal morphology (higher VH and VH/CD ratio) (P < 0.05). The XOS, IAPS and XOS + IAPS treatments increased the mRNA expression of zonula occludens-1 and occludin of the jejunum as compared with the control group (P < 0.05). Simultaneously, birds in the XOS + IAPS group showed lower plasma D-lactic acid concentration and higher mRNA expression of claudin-1, claudin-3, and occludin in the jejunum than those in the control or IAPS groups (P < 0.05). Moreover, there was no significant difference in growth performance, intestinal morphology, and intestinal barrier function of broilers between the AGP and XOS + IAPS groups. In conclusion, the combination of XOS and IAPS had a better potential as chlortetracycline substitute for improving the growth performance, intestinal morphology, and intestinal barrier function of broilers.

Unraveling the Origin of Tribomagnetization in Ferromagnetic Materials

Tribomagnetization, a natural phenomenon known for decades, has many engineering applications today. However, its intrinsic origin remains controversial and the mechanistic-based model has not yet been developed to predict the tribomagnetization behavior. In this work, the origin of tribomagnetization is investigated via both the experimental and modeling approaches. For the first time, the expansion of surface plastic deformation to the subsurface layer (i.e., dislocation strain gradient) is characterized in conjunction with the tribological behavior of the interface. By performing the reciprocating sliding experiment in a pin-on-block contact configuration, the tribomagnetization evolution in different wear regimes is followed, the geometrically necessary dislocations (GNDs) developed in the subsurface are measured, and the formation of characteristic magnetic domains is revealed. A tribomagnetization model is proposed on the basis of the sliding-induced plastic deformation mechanism with GNDs, bringing the missing link with classical tribology and ferromagnetism. The model reveals that the surface plastic strain and width of a wear scar are two crucial factors in determining the surface magnetic field changes. We believe that the tribomagnetization originates from the magnetic distortion accompanied by the progression of GNDs in the subsurface. Our hypothesis is supported by the good agreement between the model prediction and experimental observation.

Enhanced transforming growth factor-beta signaling and fibrosis in the pectoralis major muscle of broiler chickens affected by wooden breast myopathy

Fibrosis has also been recorded as a prominent pathological feature within wooden breast (WB) myopathy of broiler chickens. This study was conducted to evaluate the accumulation of fibril collagen, deposition of the extracellular matrix (ECM) components, and the underlying mechanism mediating the pathogenic fibrotic process in the pectoralis major (PM) muscle of WB-affected birds. Broiler chickens were categorized into the control and WB groups based on the evaluation of myopathic lesions. Results indicated that the total content and area of collagen in cross-sections of the PM muscle, as well as the augmented expression of collagen-I and fibronectin in the ECM, were greatly increased in birds with WB. Wooden breast myopathy upregulated expressions of transforming growth factor-beta (TGF-β) and the phosphorylation of Smad 2 and 3, thereby activating TGF-β-mediated Smad signaling pathway, which further enhanced the transcription of profibrotic mediators. In addition, regulators involved in collagen biosynthesis and cross-linking including prolyl 4-hydroxylase, lysyl oxidase, lysyl hydroxylase, and decorin were increased in the WB muscle. Finally, the expressions of both matrix metalloproteinases (MMP) and tissue inhibitor of metalloproteinases (TIMP) were increased in the WB muscle, which might be related with reduced ECM remodeling. Overall, WB myopathy induces severe fibrosis by enhancing ECM deposition and collagen cross-linking in the PM muscle of broiler chickens, possibly via the activation of TGF-β signaling and the dysregulation of the MMP and TIMP system.

Microbiota populations and short-chain fatty acids production in cecum of immunosuppressed broilers consuming diets containing γ-irradiated Astragalus polysaccharides

This study was designed to evaluate the effects of γ-irradiated Astragalus polysaccharides (IAPS) on growth performance, cecal microbiota populations, and concentrations of cecal short-chain fatty acids of immunosuppressed broilers. A total of 144 one-day-old broiler chicks were randomly assigned into 3 groups: nontreated group (control), cyclophosphamide (CPM)-treated groups fed either a basal diet or the diets containing 900 mg/kg IAPS, respectively. On day 16, 18, and 20, broilers in the control group were intramuscularly injected with 0.5 mL sterilized saline (0.75%, wt/vol), and those in the CPM and IAPS groups were intramuscularly injected with 0.5 mL CPM (40 mg/kg of BW). The trial lasted 21 d. Compared with the control group, CPM treatment decreased the broiler average daily gain (ADG) and feed intake (P < 0.05) but did not affect the overall microbial diversity and compositions, as well as the concentrations of cecal acetate, propionate, and butyrate in cecum of broilers (P > 0.05). Dietary IAPS supplementation increased broiler ADG, Shannon index, and decreased Simpson index (P < 0.05). Specifically, broilers fed diets containing IAPS showed lower abundances of Faecalibacterium, Bacteroides, and Butyricicoccus and higher proportions of Ruminococcaceae UCG-014, Negativibacillus, Shuttleworthia, Sellimonas, and Mollicutes RF39_norank, respectively (P < 0.05). The IAPS treatment also increased butyrate concentration (P < 0.05) and tended to elevate acetate concentration (P = 0.052) in cecal digesta. The results indicated that IAPS are effective in increasing the cecal beneficial bacteria and short-chain fatty acids production, contributing to improvement in the growth performance of immunosuppressive broilers. These findings may expand our knowledge about the function of modified Astragalus polysaccharides in broiler chickens.

MiR-605-3p inhibits malignant progression of prostate cancer by up-regulating EZH2

OBJECTIVE

This study aimed to investigate the effect of microRNA-605-3p (miR-605-3p) on cell proliferation, invasion and migration in prostate cancer cells, as well as its effects on the Enhancer Zeste Homolog 2 (EZH2) expression and the potential regulatory mechanisms.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was applied to detect the miR-605-3p expression in 52 pairs of Prostate Cancer (PCa) tissues and normal tissues, and to analyze the relationship between miR-605-3p expression and PCa pathological parameters. MiR-605-3p mimics were transfected into PCa cell line PC-3 and DU145 to achieve miR-605-3p overexpression. Then, Cell Counting Kit-8 (CCK-8), cell colony formation assay and transwell invasion and migration assay were performed to analyze miR-605-3p's effect on the biological function of prostate cancer cells. Finally, the potential mechanisms of downstream genes were explored through bioinformatics analysis and recovery experiments.

RESULTS

We found that miR-605-3p expression in PCa was markedly lower than that in normal tissues. Patients with low miR-605-3p expression had higher tumor stage, higher incidence of lymph node metastasis and distant metastasis. In vitro analysis showed that miR-605-3p overexpression leads to a significant decrease in cell proliferation, invasion and migration ability. Subsequently, it was verified in cell line and tissue that EZH2 expression was remarkably increased in PCa, which was negatively correlated with miR-605-3p expression. In addition, the recovery experiment found that EZH2 can counteract the role of miR-605-3p in PCa, together they affected the malignant progression of PCa.

CONCLUSIONS

MiR-605-3p was significantly associated with PCa stage, lymph node metastasis and distant metastasis and the poor prognosis; besides, it can inhibit the malignant progression of PCa. In addition, the study showed that miR-605-3p may inhibit the proliferation, invasion and migration ability of PCa by regulating EZH2.

French Health big data experience: The evolution of the national health insurance information system

The French national health insurance information system created in 1999 is one of the largest global data warehouse of medico-administrative data, covering nearly 66 million inhabitants and containing more than 160 billion records, including all outpatient health expenditures. Recent legislation has enlarged the scope of information and access to the data warehouse. Initially created to reimburse patients, the national health insurance data warehouse has developed into a powerful tool for conducting public health research.

Public health researchers and epidemiologists have long studied population health determinants, including access to and impact of health care interventions, through hypothesis driven investigations based on experimental (randomized controlled trials) or quasi-experimental designs (e.g. cohort or case control studies). In such studies, efforts are centred on data validity rather than scope or volume. Nowadays the availability of medical claims and electronic health records (eHR) allows users not only to address similar research questions at no or little cost for data collection, but also to extend the scope of research questions to the analysis of care pathways, the evaluation of public health policies, the impact of interventions in real-life conditions.

Striding away from the conventional hypothesis driven research paradigm, public health researchers have started exploring the power of applying data mining approaches on eHR. As demonstrated in the omics revolution, data driven approaches are discovery-generating tools with explanatory and predictive power. Could data mining methods applied to eHR deliver similar breakthroughs in Health Services Research? What new knowledge and tools must the public health research community acquire to embrace this new research paradigm? These are the issues that we will discuss, with illustrations, during this presentation.

Polydatin Attenuates 14.1 MeV Neutron-Induced Injuries via Regulating the Apoptosis and Antioxidative Pathways and Improving the Hematopoiesis of Mice

With more powerful penetrability and ionizing capability, high energetic neutron radiation (HENR) often poses greater threats than photon radiation, especially on such occasions as nuclear bomb exposure, nuclear accidents, aerospace conduction, and neutron-based radiotherapy. Therefore, there emerges an urgent unmet demand in exploring highly efficient radioprotectants against HENR. In the present study, high-throughput 14.1 MeV neutrons were generated by the high-intensity D-T fusion neutron generator (HINEG) and succeeded in establishing the acute radiation syndrome (ARS) mouse model induced by HENR. A series of preclinical studies, including morphopathological assessment, flow cytometry, peripheral complete blood, and bone marrow karyocyte counting, were applied showing much more serious detriments of HENR than the photon radiation. In specific, it was indicated that surviving fraction of polydatin- (PD-) treated mice could appreciably increase to up to 100% when they were exposed to HENR. Moreover, polydatin contributed much in alleviating the HENR-induced mouse body weight loss, spleen and testis indexes decrease, and the microstructure alterations of both the spleen and the bone marrow. Furthermore, we found that the HENR-damaged hematopoiesis was greatly prevented by PD treatment in such aspects as bone marrow hemocytogenesis, splenocytes balancing, or even the peripheral blood cellularity. The additional IHC investigations revealed that PD could exert potent hematopoiesis-promoting effects against HENR via suppressing apoptosis and promoting the antioxidative enzymes such as HO-1.

[Analysis of clinical characteristics of 49 cases of COVID-19]

Objective: To analyze the epidemiological and clinical characteristics, and imaging features of patients with COVID-19 in Henan Province People's Hospital. Methods: The epidemiology, clinical symptoms, laboratory and radiologic data of 49 patients with COVID-19 infection admitted to the department of infectious disease in our hospital from January 23, 2020 to February 22, 2020 were retrospectively analyzed. All analyses were performed with SPSS software, version 22.0. Results: A total of 49 patients with COVID-19 were enrolled, of which 28 were ordinary, 16 were severe, and 5 were critical in disease severity. The average ages of the 3 groups were (46±19) , (60±16) and (68±20) years, with statistical differences (P=0.015). Common symptoms at the onset were fever (41 patients), dry cough (35 patients), and fatigue (21 patients). Epidemiological investigations found that 31 (63%) patients had direct or indirect contact with confirmed cases, and 14 cases were family clustered. Laboratory test results showed that the lymphocyte counts progressively decreased [0.85 (0.5-1.6) ×10(9)/L,0.51 (0.4-0.9) ×10(9)/L and 0.43 (0.47-0.61) ×10(9)/L, respectively], while LDH [162 (145.1-203.5) U/L,265 (195.3-288.4) U/L and 387 (312.3-415.5) U/L, respectively] and D-dimer [0.15 (0.09-0.40) mg/L,0.4 (0.2-0.6) mg/L and 0.9 (0.5-1.4) mg/L, respectively] were significantly increased (P<0.05), in all the 3 groups. The levels of IL-6 [(43.2±15.4) μg/L, (78.5±31.2) μg/L and (132.4±47.9) μg/L, respectively] and IL-10 [(3.5±3.2) μg/L, (7.6±6.4) μg/L and (9.4±7.2) μg/L respectively] increased significantly with disease severity. Pulmonary imaging of ordinary patients mainly showed unilateral or bilateral multiple infiltrates, while severe and critically ill patients showed diffuse exudation and consolidation of both lungs, and a few patients showed signs of "white lungs". Conclusions: Patients with COVID-19 has a definite history of contact with diagnosed patients, and has family aggregation. The clinical symptoms were mainly fever and dry cough. Laboratory results showed that lymphocyte count, LDH, D-dimer, interleukin-6 and interleukin-10 levels had a significant correlation with the severity of the disease, which could be used as markers for disease progression and prognosis. Pulmonary imaging showed unilateral or bilateral ground glass infiltration. In severe and critically ill patients, diffuse infiltration and consolidation or even "white lung" were present.

MiR-431 suppresses proliferation and metastasis of lung cancer via down-regulating DDX5

OBJECTIVE

We aimed to detect the role and function of microRNA-431 (miR-431) in lung cancer, and to investigate the underlying mechanism in regulating the development of lung cancer.

PATIENTS AND METHODS

Quantitative Real-time polymerase chain reaction (qRT-PCR) was utilized to measure the relative expression level of miR-431 in lung cancer tissues and cell lines. Cell counting kit-8 (CCK-8) and colony formation assays were employed to measure the proliferative ability of lung cancer cells. Meanwhile, transwell assay was recruited to detect the invasive and migratory abilities of lung cancer cells. Furthermore, dual-luciferase reporter gene assay was designed to verify the target gene of miR-431. Western blot assay was used to gauge the protein level of DDX5 (DEAD box polypeptide 5).

RESULTS

MiR-431 expression was significantly lower in 122 lung cancer tissue samples or cell lines compared to the adjacent normal tissues or lung bronchial epithelial cell line, respectively. Over-expression of miR-431 significantly inhibited proliferation, invasion and migration of A549 cells. Down-regulation of miR-431 accelerated cell growth and metastasis of H1650 cells. DDX5 was proved to be a direct target for miR-431 in lung cancer.

CONCLUSIONS

MiR-431 expression decreased in lung cancer tissues and cells. MiR-431 suppressed proliferation, invasion and migration of lung cancer cells via inhibiting the expression of DDX5. Our study might provide a novel target for the biological therapy of lung cancer.

Glucose and lipid metabolism of broiler chickens fed diets with graded levels of corn resistant starch

1. The aim of this study was to investigate the effects of graded levels of dietary corn resistant starch (RS) on glucose and lipid metabolism of broilers. 2. A total of 320 male broiler chicks (Arbor Acres, one-day-old) were randomly allocated to five dietary treatments, including a corn-soybean control diet, a corn-soybean based diet containing 20% corn starch, and three diets containing 4%, 8% and 12% RS by replacing corn starch with 6.67%, 13.33% and 20% Hi-Maize® 260 (identified as control, RS1, RS2, RS3 and RS4, respectively). Each treatment contained eight replicates with eight birds, and the experiment lasted 42 days. 3. Birds fed RS diets showed lower (P < 0.05) concentrations of serum low-density lipoprotein cholesterol and non-esterified fatty acid (NEFA) at d 21 and 42 of age, compared to the control. Lower (P < 0.05) hepatic apolipoprotein B concentration and citrate synthase (CS) activity, as well as a higher (P < 0.05) glycogen synthase (GS) concentration were observed in birds fed RS diets than those in the control group at d 21 of age. Consuming RS diets linearly increased (P < 0.01) serum glucose concentration, and linearly decreased (P < 0.01) NEFA concentrations in broilers at d 21 and 42 of age. Liver GS concentration and activities of hexokinase, pyruvate and CS were linearly increased (P < 0.01) in broilers at d 21 of age, but were linearly decreased (P < 0.05) in birds at d 42 of age in response to the increase of dietary RS levels. Feeding RS diets linearly decreased (P < 0.05) mRNA expressions of PC, PPARα and CPT-1 at d 21 of age and the mRNA expressions of SREBP-1 c, ChREBP, ACC and FAS at d 42 of age, and linearly increased (P < 0.05) the mRNA expressions of PEPCK, PC, LKB1, AMPKα1, PPARα, CPT-1 and L-FABP at d 42 of age. 4. Feeding broilers with diets containing higher concentration of RS promoted hepatic lipolysis and gluconeogenesis through activated AMPK signalling pathway and accelerated whole-body energy expenditures in the grower phase.

Serum miR-17 levels in patients with hepatitis B virus induced liver fibrosis

OBJECTIVE

To investigate the clinical significance of detecting serum level of miR-17 in patients with hepatitis B virus (HBV) induced liver fibrosis.

PATIENTS AND METHODS

A total of 200 HBV patients undergoing liver biopsy in Henan Provincial People's Hospital from June 2016 to December 2018, and 200 healthy subjects during the same period were included. Serum miR-17 level was detected by qRT-PCR. Multivariate Logistic regression analysis was conducted to evaluate independent risk factors of liver fibrosis in HBV patients. Meanwhile, ROC curves were used to assess the value of miR-17 in determining liver fibrosis severity of HBV patients.

RESULTS

200 HBV patients were classified into 4 groups based on the severity of liver fibrosis, including 52 cases in S0-1, 47 cases in S2, 53 cases in S3, and 48 cases in S4. Serum level of miR-17 was lower in healthy subjects than that in HBV patients. In addition, the serum level of miR-17 was negatively correlated with liver fibrosis severity. The relative levels of aspartate aminotransferase (AST), HBV-DNA, albumin (ALB), platelets (PLT), aspartate aminotransferase-to-platelet ratio index (APRI) and miR-17 were the independent factors of advanced liver fibrosis in HBV patients. Serum level of miR-17 exerted a predictive potential in diagnosis of the severity of HBV-induced liver fibrosis.

CONCLUSIONS

Serum miR-17 level is highly expressed in HBV patients, and negatively correlated with liver fibrosis severity, which could be utilized as a non-invasive hallmark assessing liver fibrosis severity in HBV patients.

Effect of Crystal Symmetry on the Spin States of Fe3+ and Vibration Modes in Lead-free Double-Perovskite Cs2AgBi(Fe)Br6

We show by electron spin resonance (ESR) and Raman spectroscopies that the crystal phase transition of the lead-free double-perovskite Cs₂AgBiBr₆ has a profound symmetry-breaking effect on the high spin states of, for example, a transition-metal ion Fe³⁺ and the vibrational modes. It lifts their degeneracy when the crystal undergoes the cubic-tetragonal phase transition, splitting the six-fold degenerate S = 5/2 state of Fe³⁺ to three Kramer doublets and the enharmonic breathing mode T_g of the MBr₆ octahedra (M = Ag, Bi, Fe) into E_g + A_g. The magnitudes of both spin and Raman line splitting are shown to directly correlate with the strength of the tetragonal strain field. This work, in turn, demonstrates the power of the ESR and Raman spectroscopies in probing structural phase transitions and in providing in-depth information on the interplay between the structural, spin, and vibrational properties of lead-free double perovskites, a newly emerging and promising class of materials for low-cost and high-efficiency photovoltaics and optoelectronics.