Static and dynamic disorder in Aß40 fibrils.

Deposition of Aß aggregates in the form of amyloid fibrils is a pathological hallmark of Alzheimer's disease. Understanding the structure and dynamics of Aß fibrils is important for delineating the mechanism of Aß aggregation and developing effective therapeutic strategies. Here we used site-directed spin labeling and EPR spectroscopy to study the Aß40 fibril structure and dynamics. We obtained the EPR spectra of 40 spin-labeled Aß40 fibril samples, with spin labeling coverage of the entire Aß40 sequence. Analysis of the spin exchange interaction and spin label mobility using spectral simulations suggest that the strength of spin exchange interaction is primarily determined by static disorder in the Aß40 fibrils. EPR data suggest that the entire Aß40 sequence except residue D1 is highly ordered and the two hydrophobic regions at residues 17-20 and 31-36 show the lowest static disorder. Dynamic disorder is relatively constant across all reside positions, with residues 22 and 23 having the highest dynamic disorder. Comparison of the EPR data for Aß40 and Aß42 fibrils shows overall more ordered packing interactions in Aß40 fibrils. Another noteworthy difference is the C-terminal residue, which has high static disorder in Aß42 fibrils, but is ordered in Aß40 fibrils. The higher static disorder in Aß42 fibrils may lead to increased fragmentation, monomer dissociation, and structural defects, which may contribute to increased aggregation through secondary nucleation.

Intraperitoneal chromophore injections delay early-onset and rapid retinal cone degeneration in a mouse model of Leber congenital amaurosis.

Highly expressed in the retinal pigment epithelium (RPE), the RPE-specific 65-kDa (RPE65) enzyme is indispensable to generate 11-cis-retinal (11cRAL), a chromophore for rhodopsin and cone photopigments. RPE65 deficiency can lead to Leber congenital amaurosis type 2 (LCA2), in which the isomerization of photobleached all-trans-retinal into photosensitive 11cRAL is blocked, ultimately causing severe retinal dysfunction and degeneration. The related mouse models, which are constructed through gene knockout or caused by spontaneous mutations, morphologically present with early-onset and rapid retinal cone cells degeneration, including loss of short-wavelength-sensitive cone opsins (S-opsins) and mislocalization of medium-wavelength-sensitive cone opsins (M-opsins). Studies have shown that routine Rpe65 gene replacement therapy, mediated by an adeno-associated virus (AAV) vector, can restore RPE65 protein. However, AAV transfection and Rpe65 transgene expression require at least one to two weeks, and the treatment cannot fully block the early-onset cone degeneration. To determine the feasibility of delaying cone degeneration before gene therapy, we investigated the impact of 11cRAL treatment in an early-age LCA2 retinal degeneration 12 (rd12) mouse model. Similar to human patients, the mouse model carries a spontaneous mutation in the Rpe65 gene, which results in disrupted endogenous 11cRAL regeneration. We found that RPE65 deficiency did not notably affect rodent retinal vessels. Under red light illumination, the rd12 mice were intraperitoneally injected with exogenous 11cRAL from postnatal day (P) 14 to P21. Three days after the last injection, a notable recovery of retinal function was observed using scotopic and photopic electroretinograms. Using optical coherence tomography and histological analyses of the deficient retinas, we found changes in the thickness of the photoreceptor outer segment (OS); this change could be rescued by early 11cRAL treatment. In addition, the treatment notably preserved M- and S-opsins, both of which maintained appropriate localization inside cone cells, as shown by the wild-type mice. In contrast, the age-matched untreated rd12 mice were characterized by retinal S-opsin loss and M-opsin mislocalization from the photoreceptor OS to the inner segment, outer nuclear layer, or outer plexiform layer. Notably, 11cRAL treatment could not maintain retinal function for a long time. Ten days after the last injection, the rod and M-cone electroretinograms significantly decreased, and S-cone responses almost extinguished. Our findings suggest that early 11cRAL treatment is useful for restoring retinal function and rescuing morphology in the rd12 mouse model, and the early-onset and rapid cone degeneration can be delayed before gene therapy.

[Relationship of Cystic Fibrosis Transmembrane Conductance Regulator Expression with Clinical Features and Prognosis in Patients with Acute Leukemia].

OBJECTIVE: To investigate the expression of cystic fibrosis transmembrane conductance regulator (CFTR) protein in patients with acute leukemia and its relationship to clinical features and prognosis of acute leukemia. METHODS: A total of115 patients with acute leukemia were enrolled in the experimental group and 20 healthy individuals were used as control. Peripheral blood or bone marrow samples were collected, and mononuclear cells were isolated. The expression of CFTR protein was detected by Western blot. The relationships of CFTR protein expression to clinical features and prognosis was analyzed. RESULTS: The expression of CFTR protein was not detected in peripheral blood mononuclear cells of normal control, while it was positive in more than half of acute leukemias including acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), but negative in the patients with acute promyelocytic leukemia (M3). In the patients with AML, there was no difference in peripheral white blood cells (WBC), peripheral blast cells, platelet and hemoglobin (HGB) between CFTR-positive and CFTR-negative patients. There was no relationship between the expression of CFTR protein and gene mutations such as NPM1, CEBPA, FLT3-ITD, and C-Kit. Complete remission (CR) rate after two course in CFTR-negative patients was slightly higher than that in positive patients. The survival time of CFTR-negative patients was little longer than that of positive patients, but the difference was not statistically significant. CONCLUSIONS: The expression of CFTR protein seems not associated with clinical features, treatment response and prognosis in the patients with acute leukemia.

[The Roles of Glut5 in Imatinib Resistance in the Ph+ Acute Lymphoblastic Leukemia Cell].

OBJECTIVES: To explore the possible roles of glucose transport 5 (Glut5) in imatinib resistance in the Ph+ acute lymphoblastic leukemia cell (Ph+ ALL). METHODS: The gene chip technique was used to detect different gene expression between Ph+ ALL cell line SUP-B15/R (imatinib resistant cell line) and SUP-B15/S (imatinib sensitive cell line), the gene of solute carrier family 2 member 5 (SLC2A5) and its coded protein Glut5 were screened out and were reconfirmed by qPCR and Western blot assay. The imatinib half maximal inhibitory concentration (IC50) to SUP-B15/S cells with or without fructose treatment was further detected by MTT assay, simultaneously signal pathway gene was detected by qPCR assay. RESULTS: Metabolism related gene SLC2A5 was screened out with gene chip technique and the Western blot assay and qPCR confirmed the high expression of SLC2A5 gene and its coded protein Glut5 in SUP-B15/R cells. IC50 values of imatinib to SUP-B15/S cells after treatment with 25 µmol/L fructose were increased from (44.50±2.38) µmol/L to (64.71±1.69) µmol/L, in the meanwhile, PI3K and AKT mRNA level also increased in fructose treated SUP-B15/S cells compared to the control. CONCLUSIONS: High expression of SLC2A5 and Glut5 protein in SUP-B15/R cells leads to increased fructose absorption, and further activates PI3K/AKT pathway which cause the SUP-B15 cell resistance to imatinib.

Delineation of riparian areas based on the application of two-dimension hydraulic modelling.

This paper presents a proposal for riparian area delineation relying on topographical, hydrological, vegetation, and soil data together with numerical modelling of the river hydrodynamics. The two-dimensional model Iber is used to simulate 2.5, 10, 50, and 100-years return period flood events, and new code is developed to simulate the main hydrological processes of the river-riparian system to generate riparian zone maps. Results show that changes in topography and discharge direction between river and groundwater both influence the riparian area extent, and that temporal evolution of the riparian zone is much slower than that of the flood, and its extension can continue to increase while the flood recedes, but only to a certain extent, conditioned by topography, soil characteristics, and vegetation. A simple but efficient numerical code for understanding and simulating the riparian dynamics has been developed, which constitutes a proposal for a new riparian delineation approach useful for research and management applications, and which can also be a useful tool for gaining a better understanding of the riparian boundary behavior under different ecohydrological conditions.

Polydopamine based photothermal/photodynamic synchronous coating modified intraocular lens for efficient and safer posterior capsule opacification prevention.

Posterior capsule opacification (PCO), as one of the most common late complications after intraocular lens (IOL) implantation in cataract surgery, seriously affects patients' postoperative vision and surgical satisfaction, and can only be treated by laser incision of the posterior capsule. Although drug eluting coating modification have been proved to inhibit PCO effectively, the complicated coating methods and the potential toxicity of the antiproliferative drugs hinders its actual application. In this study, an indocyanine green (ICG) loaded polydopamine (PDA) coating modified IOL (IP-IOL) was designed to prevented PCO. In vitro and in vivo studies have shown that IP-IOL can effectively eliminate lens epithelial cells and significantly reduce the degree of PCO. At the same time, it still has good imaging quality and optical properties. Furthermore, both the near-infrared irradiation and ICG loaded PDA coating modified IOLs have proved to possess high biological safety to eyes. Thus, with easy preparation and safer near-infrared irradiated photothermal/photodynamic synchronous properties, such ICG loaded PDA coating provides an effective yet easier and safer PCO prevention after IOL implantation.

EPR Studies of Aß42 Oligomers Indicate a Parallel In-Register ß-Sheet Structure.

Aß aggregation leads to the formation of both insoluble amyloid fibrils and soluble oligomers. Understanding the structures of Aß oligomers is important for delineating the mechanism of Aß aggregation and developing effective therapeutics. Here, we use site-directed spin labeling and electron paramagnetic resonance (EPR) spectroscopy to study Aß42 oligomers prepared by using the protocol of Aß-derived diffusible ligands. We obtained the EPR spectra of 37 Aß42 oligomer samples, each spin-labeled at a unique residue position of the Aß42 sequence. Analysis of the disordered EPR components shows that the N-terminal region has a lower local structural stability. Spin label mobility analysis reveals three structured segments at residues 9-11, 15-22, and 30-40. Intermolecular spin-spin interactions indicate a parallel in-register ß-sheet structure, with residues 34-38 forming the structural core. Residues 16-21 also adopt the parallel in-register ß-structure, albeit with weaker intermolecular packing. Our results suggest that there is a structural class of Aß oligomers that adopt fibril-like conformations.

Sleep disorders in chronic pain and its neurochemical mechanisms: a narrative review.

Chronic pain (CP) is a prevalent problem, and more than half of patients with CP have sleep disorders. CP comorbidity with sleep disorders imposes immense suffering and seriously affects the patient's quality of life, which is a challenging issue encountered by clinicians. Although the reciprocal interactions between pain and sleep have been studied to some degree, there is still a lack of awareness and comprehensive description of CP comorbidity with sleep disorders. In this narrative review article, we summarize the current knowledge about the present estimates of the prevalence of comorbid sleep disorders in CP patients, sleep detection methods, sleep characterization in CP, and the effect of sleep disorders on CP and current therapies. We also summarize current knowledge of the neurochemical mechanisms of CP comorbidity with sleep disorders. In conclusion, insufficient attention has been paid to the role of sleep disorders in CP patients, and CP patients should be screened for sleep disorders in the clinic. Special attention should be given to a possible risk of drug-drug interaction when using two types of drugs targeting pain and sleep simultaneously. The current insight into the neurobiological mechanisms underlying CP comorbidity with sleep disorders is still rather limited.

Environment friendly superhydrophobic and transparent surface coating via layer-by-layer self-assembly for antifogging of optical lenses.

The fogging of the optical lenses seriously affects the life quality and safety, which is due to the gathering of the humid air into liquid droplets on the solid surface because of the temperature change. Superhydrophobic coating modification is an effective way to repel the water from surface. However, due to the specific application requirements, the transparency of optical lenses after coating modification is still the challenge for the application of such superhydrophobic coatings. In this work, a superhydrophobic and transparent surface coating was fabricated by the layer-by-layer self-assembly followed with fluorination. After poly(sodium 4-styrenesulfonate) and poly(allylamine hydrochloride) (PAH) multilayer precoating was generated on the surface, the different bilayers of SiO2 nanoparticles in different particle sizes and PAH multilayers were fabricated. The obtained polyelectrolytes-nanoparticle multilayers were fluorinated by a fluorinating agent. Such polyelectrolytes-nanoparticle multilayered coating renders obvious micro-nano composite structure, showing excellent superhydrophilicity, whereas such coating modified eyeglasses keeps excellent light transparency. The results of antifogging and defogging test also proved that the eyeglass modified with this coating had good antifogging and defogging performance. Therefore, such polyelectrolytes-nanoparticle multilayered coating with excellent superhydrophobic and transparent properties might provide a feasible approach for the practical antifogging application of optical lenses.

Rapid and Economical Drug-Eluting IOL Preparation via Thermoresponsive Agarose Coating for Effective Posterior Capsular Opacification Prevention.

Posterior capsular opacification (PCO), the highest incidence complication after cataract surgery, is mainly due to the attachment, proliferation, and migration of the residual lens epithelial cells (LECs). Although the drug-eluting IOLs have been proved to be an effective way to prevent PCO incidence, its preparations are time consuming and require tedious preparation steps. Herein, the thermoreversible agarose is adopted to prepare drug-eluting IOL. Such functional coating can be obtained easily by simple immersion in the antiproliferative drug containing hot agarose and taken out for cooling, which not only does not affect the optical property but also can effectively decrease the PCO incidence after intraocular implantation. As a result, the proposed agarose coating provides a rapid and economical alternative of drug-eluting IOL fabrication for PCO prevention.

A unique understanding of traditional medicine of pomegranate, Punica granatum L. and its current research status.

ETHNOPHARMACOLOGICAL RELEVANCE: Pomegranate, Punica granatum L., has been used in traditional medicine in China and several regions of the world including Ayurveda, Islamic, and Persian for the treatment of atherosclerosis, diabetes, hypertension, hyperlipidemia, and several types of cancer, as well as for peptic ulcer and oral diseases for hundreds of years. Presently, pomegranate is treated as both a "medicine food homology" herbal medicine and a healthy food supplemental product. AIM OF THE STUDY: The aim of this work is to develop an overview of pomegranate in the context of the status of its traditional medicine theories, the spread along the Silk Road, ethnopharmacological uses, chemical compositions, pharmacological activities, toxicology, and the involved pathways. MATERIALS AND METHODS: Information on P. granatum L. was acquired from published materials, including monographs on medicinal plants, ancient and modern recorded classical texts; and pharmacopoeias and electronic databases (PubMed, Science Direct, Web of Science, Google Scholar, CNKI, and Wanfang Data). RESULTS: Pomegranate has been used in many traditional medical systems throughout history. It is widely cultivated in Central Asia and spread throughout China along the Silk Road. Many phytochemicals, such as tannins, organic acids, flavonoids, alkaloids, and volatile oils have been identified from different parts of pomegranate, these compounds have a wide range of activities, including antioxidant, antimicrobial, and anti-oncogenic properties, as well as conferring resistance to cerebrovascular disease. Furthermore, A summary of the four promising pharmacological pathways is provided. CONCLUSIONS: The traditional uses, chemical compositions, pharmacological activities, and signaling pathways of pomegranate are summarized comprehensively in the review. It can be treated as a guidance for the future clinical and basic research. The information provided in this review will be very useful for further studies to develop novel therapeutic directions for application of pomegranate.

[Effects of HMGB1 on Proliferation and Secretion of Human Bone Marrow Mesenchymal Stem Cells].

OBJECTIVE: To investigate the effect of high mobility group protein 1(HMGB1) on the proliferation and cytokine expression of human bone marrow mesenchymal stem cells (MSC). METHODS: Different concentrations of recombinant human HMGB1 protein (100, 200, 400, 800 and 1000 ng/ml) were incubated with MSC for 24, 48, 72 h and the proliferation of MSC were detected respectively by using the CCK-8 method and flow cytometry. The best concentrations of HMGB1 incubated with MSC was determined (200 ng/ml, 1000 ng/ml), and the flow cytomerty was used to determine the effect of HMGB1 on the proliferation of MSC. The mRNA expression levels of IL-10, TGF- ß1, TSG-6 and IFN-γ in MSC incubated with HMGB1 protein were detected by real-time quantitative PCR and ELISA. RESULTS: The result of MSC identification and flow cytometry showed that the CD105, CD73 and CD90 were expressed, but did not expression CD45, CD34, CD11b, CD19 and HLA-DR; CCK-8 showed that HMGB1 at the concentrations of 100 ng/ml, 200 ng/ml and 400 ng/ml could promote the proliferation of MSC incubated for 24, 48 and 72 h as compared with the control group (P<0.05), and the most effective concentration was 200 ng/ml; flow cytometry showed that the compared with the control group, HMGB1 200 ng/ml could induce MSC from G1 phase to S phase to promote the proliferation of MSC; QPCR showed that the mRNA expression of MSC cytokines IL-10, TGF-ß1, TSG-6 increased while IFN-γ decreased at the concentration of 200 ng/ml HMGB1 as compared with the control group. ELISA experiments showed that the HMGB1 200 ng/ml acting on MSC for 48 h could significantly promoted the secretion of IL-10, TGF-ß 1 and TSG-6(P<0．05), while IFN-γ showed no significant difference as compared with control group. CONCLUSION: Recombinant human HMGB1 can promote the proliferation and secretion of MSC in healthy people.

Polymorphic Aß42 fibrils adopt similar secondary structure but differ in cross-strand side chain stacking interactions within the same ß-sheet.

Formation of polymorphic amyloid fibrils is a common feature in neurodegenerative diseases involving protein aggregation. In Alzheimer's disease, different fibril structures may be associated with different clinical sub-types. Structural basis of fibril polymorphism is thus important for understanding the role of amyloid fibrils in the pathogenesis and progression of these diseases. Here we studied two types of Aß42 fibrils prepared under quiescent and agitated conditions. Quiescent Aß42 fibrils adopt a long and twisted morphology, while agitated fibrils are short and straight, forming large bundles via lateral association. EPR studies of these two types of Aß42 fibrils show that the secondary structure is similar in both fibril polymorphs. At the same time, agitated Aß42 fibrils show stronger interactions between spin labels across the full range of the Aß42 sequence, suggesting a more tightly packed structure. Our data suggest that cross-strand side chain packing interactions within the same ß-sheet may play a critical role in the formation of polymorphic fibrils.

Remote ischemic conditioning-induced hyperacute and acute responses of plasma proteome in healthy young male adults: a quantitative proteomic analysis / 中华医学杂志(英文版)

BACKGROUND@#Long-term remote ischemic conditioning (RIC) has been proven to be beneficial in multiple diseases, such as cerebral and cardiovascular diseases. However, the hyperacute and acute effects of a single RIC stimulus are still not clear. Quantitative proteomic analyses of plasma proteins following RIC application have been conducted in preclinical and clinical studies but exhibit high heterogeneity in results due to wide variations in experimental setups and sampling procedures. Hence, this study aimed to explore the immediate effects of RIC on plasma proteome in healthy young adults to exclude confounding factors of disease entity, such as medications and gender.@*METHODS@#Young healthy male participants were enrolled after a systematic physical examination and 6-month lifestyle observation. Individual RIC sessions included five cycles of alternative ischemia and reperfusion, each lasting for 5 min in bilateral forearms. Blood samples were collected at baseline, 5 min after RIC, and 2 h after RIC, and then samples were processed for proteomic analysis using liquid chromatography-tandem mass spectrometry method.@*RESULTS@#Proteins related to lipid metabolism (e.g., Apolipoprotein F), coagulation factors (hepatocyte growth factor activator preproprotein), members of complement cascades (mannan-binding lectin serine protease 1 isoform 2 precursor), and inflammatory responses (carboxypeptidase N catalytic chain precursor) were differentially altered at their serum levels following the RIC intervention. The most enriched pathways were protein glycosylation and complement/coagulation cascades.@*CONCLUSIONS@#One-time RIC stimulus may induce instant cellular responses like anti-inflammation, coagulation, and fibrinolysis balancing, and lipid metabolism regulation which are protective in different perspectives. Protective effects of single RIC in hyperacute and acute phases may be exploited in clinical emergency settings due to apparently beneficial alterations in plasma proteome profile. Furthermore, the beneficial effects of long-term (repeated) RIC interventions in preventing chronic cardiovascular diseases among general populations can also be expected based on our study findings.

Effects of HMGB1 on Proliferation and Secretion of Human Bone Marrow Mesenchymal Stem Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of high mobility group protein 1(HMGB1) on the proliferation and cytokine expression of human bone marrow mesenchymal stem cells (MSC).@*METHODS@#Different concentrations of recombinant human HMGB1 protein (100, 200, 400, 800 and 1000 ng/ml) were incubated with MSC for 24, 48, 72 h and the proliferation of MSC were detected respectively by using the CCK-8 method and flow cytometry. The best concentrations of HMGB1 incubated with MSC was determined (200 ng/ml, 1000 ng/ml), and the flow cytomerty was used to determine the effect of HMGB1 on the proliferation of MSC. The mRNA expression levels of IL-10, TGF- β1, TSG-6 and IFN-γ in MSC incubated with HMGB1 protein were detected by real-time quantitative PCR and ELISA.@*RESULTS@#The result of MSC identification and flow cytometry showed that the CD105, CD73 and CD90 were expressed, but did not expression CD45, CD34, CD11b, CD19 and HLA-DR; CCK-8 showed that HMGB1 at the concentrations of 100 ng/ml, 200 ng/ml and 400 ng/ml could promote the proliferation of MSC incubated for 24, 48 and 72 h as compared with the control group (P<0.05), and the most effective concentration was 200 ng/ml; flow cytometry showed that the compared with the control group, HMGB1 200 ng/ml could induce MSC from G1 phase to S phase to promote the proliferation of MSC; QPCR showed that the mRNA expression of MSC cytokines IL-10, TGF-β1, TSG-6 increased while IFN-γ decreased at the concentration of 200 ng/ml HMGB1 as compared with the control group. ELISA experiments showed that the HMGB1 200 ng/ml acting on MSC for 48 h could significantly promoted the secretion of IL-10, TGF-β 1 and TSG-6(P<0．05), while IFN-γ showed no significant difference as compared with control group.@*CONCLUSION@#Recombinant human HMGB1 can promote the proliferation and secretion of MSC in healthy people.

Increased uptake of Tc-99m-methylene diphosphonate in the jaw.

Increased uptake of Tc-99m-methylene diphosphonate in the area of jaw is a common finding on the whole body bone scan. To study its incidence, causes and clinical significance, we performed static anterior and bilateral head views on 52 consecutive patients, followed by a dental examination and a panoramic radiograph. We demonstrated that increased uptake of bone tracer in the area of jaw was observed at a high incidence, as well as its characteristic distribution. The mainly causes are some common dental diseases. These findings would better guide the diagnosis and treatment for patients.