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Bin Li

Publications and source records attributed to Bin Li.

At least 37 records · Page 2Linked to original sources
PubMed2024

Genetic evidence for causal association between migraine and dementia: a mendelian randomization study.

BACKGROUND: There is an association between migraine and dementia, however, their causal relationship remains unclear. This study employed bidirectional two-sample Mendelian randomization (MR) to investigate the potential causal relationship between migraine and dementia and its subtypes: Alzheimer's disease (AD), vascular dementia (VaD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB). METHODS: Summary-level statistics data were obtained from publicly available genome-wide association studies (GWAS) for both migraine and five types of dementia. Single nucleotide polymorphisms (SNPs) associated with migraine and each dementia subtype were selected. MR analysis was conducted using inverse variance weighting (IVW) and weighted median (WM) methods. Sensitivity analyses included Cochran's Q test, MR pleiotropy residual sum and outlier (MR-PRESSO) analysis, the intercept of MR-Egger, and leave-one-out analysis. RESULTS: Migraine showed a significant causal relationship with AD and VaD, whereas no causal relationship was observed with all-cause dementia, FTD, or DLB. Migraine may be a potential risk factor for AD (odds ratio [OR]: 1.09; 95% confidence interval [CI]: 0.02-0.14; P = 0.007), while VaD may be a potential risk factor for migraine (OR: 1.04; 95% CI: 0.02-0.06; P = 7.760E-5). Sensitivity analyses demonstrated the robustness of our findings. CONCLUSION: Our study suggest that migraine may have potential causal relationships with AD and VaD. Migraine may be a risk factor for AD, and VaD may be a risk factor for migraine. Our study contributes to unraveling the comprehensive genetic associations between migraine and various types of dementia, and our findings will enhance the academic understanding of the comorbidity between migraine and dementia.

Humans↗
PubMed2007

Influence of nutrient level on biodegradation and bioconcentration of phthalate acid esters in Chlorella vulgaris.

Influences of major nutrients (N, P) on the biodegradation and bioconcentration of dibutyl phthalate (DBP) and di-2-ethylexyl phthalate (DEHP) by Chlorella vulgaris in lake water were investigated in this work. Our study demonstrated that nutrient addition obviously influenced biodegradation rate constants and apparent bioconcentration factors (BCFs) of DBP and DEHP in Chlorella vulgaris. The effects of P addition on biodegradation were less pronounced than the effects of N addition as a result of N-limitation status of phytoplankton in the lake water, while addition of both N and P more greatly affected biodegradation than addition of N or P. BCFs of DBP and DEHP decreased with increasing algal exudate as measured by dissolved organic carbon (DOC) and a strong correlation between BCFs and DOC was obtained. The results indicate that DOC plays an important role in the bioconcentration of DBP and DEHP.

Biodegradation, Environmental↗
PubMed2006

RGD peptide-conjugated poly(dimethylsiloxane) promotes adhesion, proliferation, and collagen secretion of human fibroblasts.

A novel technique for conjugating Arg-Gly-Asp (RGD) peptides to poly(dimethylsiloxane) (PDMS) surfaces as well as its application to cell culture is presented in this paper. This technique performs RGD conjugation to PDMS through photochemical immobilization of functional NHS groups to PDMS surface followed with linking RGD peptide to the surface via coupling reaction with NHS. A bifunctional photolinker, N-sulfosuccinimidyl-6-(4'-azido-2'-nitrophenylamino)hexanoate (sulfo-SANPAH), was used to conjugate RGD peptide to the surface. Compared to existing methods for peptide conjugation to PDMS, this technique is convenient, efficient, and free of organic contamination to PDMS surfaces. It can also be used to conjugate other peptides or proteins to most polymeric materials. In addition, cell culture studies showed that the RGD-conjugated PDMS surfaces promoted the adhesion, proliferation, and collagen production of human skin fibroblasts (HSFs). Finally, the RGD-conjugated PDMS surfaces are resistant to autoclaving and UV irradiation, which enables them to be repeatedly used in cell culture studies.

Biocompatible Materials↗
PubMed2006

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry assay for organophosphorus toxicants bound to human albumin at Tyr411.

Our goal was to determine whether chlorpyrifos oxon, dichlorvos, diisopropylfluorophosphate (DFP), and sarin covalently bind to human albumin. Human albumin or plasma was treated with organophosphorus (OP) agent at alkaline pH, digested with pepsin at pH 2.3, and analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Two singly charged peaks m/z 1718 and 1831, corresponding to the unlabeled peptide fragments containing the active site Tyr411 residue, were detected in all samples. The sequences of the two peptides were VRYTKKVPQVSTPTL and LVRYTKKVPQVSTPTL. The peptide-OP adducts of these peptides were also found. They had masses of 1854 and 1967 for chlorpyrifos oxon, 1825 and 1938 for dichlorvos, 1881 and 1994 for DFP, and 1838 and 1938 for sarin; these masses fit a mechanism whereby OP bound covalently to Tyr411. The binding of DFP to Tyr411 of human albumin was confirmed by electrospray tandem mass spectrometry and analysis of product ions. None of the OP-albumin adducts lost an alkoxy group, leading to the conclusion that aging did not occur. Our results show that OP pesticides and nerve agents bind covalently to human albumin at Tyr411. The presence of Tyr411 on an exposed surface of albumin suggests that an antibody response could be generated against OP-albumin adducts.

Amino Acid Sequence↗
PubMed2006

Sensitivity of butyrylcholinesterase knockout mice to (--)-huperzine A and donepezil suggests humans with butyrylcholinesterase deficiency may not tolerate these Alzheimer's disease drugs and indicates butyrylcholinesterase function in neurotransmission.

Butyrylcholinesterase (EC 3.1.1.8 BChE) is present in all human and mouse tissues, and is more abundant than acetylcholinesterase (EC 3.1.1.7 AChE) in all tissues except brain. People who have no BChE activity due to a genetic variation are healthy. This has led to the hypothesis that BChE has no physiological function. We tested this hypothesis by challenging BChE and AChE knockout mice, as well as wild-type mice, with the AChE specific inhibitors, (--)-huperzine A and donepezil, and with serine hydrolase inhibitors, echothiophate and chlorpyrifos oxon. (--)-Huperzine A and donepezil caused mortality and significant toxicity in the BChE-/- animals. The BChE heterozygote (BCHE+/-) mice with approximately one-half the BChE activity of the BChE wild type (BChE+/+) exhibited intermediate toxic symptoms, and survived a longer period. The BChE+/+ animals displayed comparatively minor toxic symptoms and recovered by 24h post-dosing. Plasma AChE activity was inhibited to the same extent in BChE-/-, +/-, and +/+ mice, whereas BChE activity was not inhibited. This indicated that the protective effect of BChE was not due to scavenging (--)-huperzine A. AChE-/- mice were unaffected by (--)-huperzine A and donepezil, demonstrating the specificity of these inhibitors for AChE. AChE-/- mice treated with chlorpyrifos oxon lost all BChE activity, had severe cholinergic symptoms and died of convulsions. This showed that BChE activity was essential for survival of AChE-/- mice. In conclusion, we propose that the protective effect of BChE is explained by hydrolysis of excess acetylcholine in physiologically relevant regions such as diaphragm, cardiac muscle, and brain. Thus, BChE has a function in neurotransmission. People with BChE deficiency are expected to be intolerant of standard doses of the anti-Alzheimer's drugs, (--)-huperzine A and donepezil.

Acetylcholine↗
PubMed2006

Electronic stabilization effects: three new K-In-T (T = Mg, Au, Zn) network compounds.

The ternary compounds K(34)In(91.05(9))Mg(13.95(9)) (I), K(34)In(96.19(6))Au(8.81(6)) (II), and K(34)In(89.95(1))Zn(13.05(7)) (III) have been synthesized by high-temperature means and structurally characterized by single-crystal X-ray diffraction methods. All are analogues of earlier products in which Li is substituted for some In in a hypothetical K(34)In(105) lattice. They consist of complex three-dimensional anionic networks built of In(12) icosahedra and M(28) triply fused icosahedra (M = In or In/T and T = Mg, Au, or Zn). The K atoms bridge between cluster faces or edges and form K(136) clathrate-IotaIota type networks. Two neighboring M(28) units are interconnected by an M atom to form a sandwich complex (M(28))M(M(28)) in I and II or by a Zn-Zn dimer in (M(28))ZnZn(M(28)) in III. Mixed In/T sites only occur in the M(28) portions. Phase stabilization through electronic tuning is present in all three via substitution of the electron-poorer T elements for In. Extended Hückel analyses indicate that all metal-metal bonding within the M(28) cluster appears to be optimized in I and III even though both are metallic. The size of the substituted element is also important in the structural features, as is especially shown by the Zn compound.

Journal Article↗
PubMed2006

Rapid reversion of sequence polymorphisms dominates early human immunodeficiency virus type 1 evolution.

The error-prone replication of human immunodeficiency virus type 1 (HIV-1) enables it to continuously evade host CD8+ T-cell responses. The observed transmission, and potential accumulation, of CD8+ T-cell escape mutations in the population may suggest a gradual adaptation of HIV-1 to immune pressures. Recent reports, however, have highlighted the propensity of some escape mutations to revert upon transmission to a new host in order to restore efficient replication capacity. To more specifically address the role of reversions in early HIV-1 evolution, we examined sequence polymorphisms arising across the HIV-1 genome in seven subjects followed longitudinally 1 year from primary infection. As expected, numerous nonsynonymous mutations were associated with described CD8+ T-cell epitopes, supporting a prominent role for cellular immune responses in driving early HIV-1 evolution. Strikingly, however, a substantial proportion of substitutions (42%) reverted toward the clade B consensus sequence, with nearly one-quarter of them located within defined CD8 epitopes not restricted by the contemporary host's HLA. More importantly, these reversions arose significantly faster than forward mutations, with the most rapidly reverting mutations preferentially arising within structurally conserved residues. These data suggest that many transmitted mutations likely incur a fitness cost that is recovered through retrieval of an optimal, or ancestral, form of the virus. The propensity of mutations to revert may limit the accumulation of immune pressure-driven mutations in the population, thus preserving critical CD8+ T-cell epitopes as vaccine targets, and argue against an unremitting adaptation of HIV-1 to host immune pressures.

CD8-Positive T-Lymphocytes↗
PubMed2006

[The inhibitory effect of paclitaxel nanoparticles on ovarian cancer xenografts and lymphatic targeting].

OBJECTIVE: To develop a polymeric drug delivery system for paclitaxel and determine whether paclitaxel can inhibit the growth of ovarian carcinoma xenografts in F344 rats by intraperitoneal administration. METHODS: Paclitaxel loading nanoparticles (PLA) were synthesized by ultrasonic emulsification; rat ovarian carcinoma cells were injected into the peritoneal cavity of F344 rats. The antitumor effect of paclitaxel nanoparticles in vivo has been evaluated by measuring tumor weight and ascite volume. At the end of the procedure the rats were killed, tumors were excised and processed for PCNA staining, tissue terminal deoxynucleotide transferase-mediated dUTP nick and labeling (TUNEL) assay. Paclitaxel concentration in plasma, pelvic lymph nodes, liver, heart were determined by high-performance liquid chromatography (HPLC). RESULTS: In the implanted carcinoma cells, paclitaxel nanoparticles significantly reduced tumor weight [(4.55 +/- 0.11) g vs (10.13 +/- 0.52) g]and ascites volume [(3.55 +/- 0.50) mL vs (30.45 +/- 1.55) mL], and induced apoptosis of tumor cells [(105 +/- 15) vs (55 +/- 10)]. The paclitaxel concentration of pelvic lymph nodes in PLA treated animals was significantly higher than that of free PTX treated animals 48 h after intraperitoneal administration [(0.75 +/- 0.05) microg/g vs (0.188 +/- 0.045) microg/g]. CONCLUSION: The intraperitoneal administration of paclitaxel nanoparticles can significantly inhibit the progression of ovarian carcinoma in peritoneal cavity of female F344 rats. The paclitaxel nanoparticle is safe and lymphatic targeting.

Animals↗
PubMed2006

[Dynamic observation of brainstem auditory evoked potential and pathological changes of the brain after closed brain injuries in rats].

OBJECTIVE: To investigate the dynamic experiences of pathological changes in brain and the injured role of brainstem auditory evoked potential (BAEP) after closed Mild Traumatic Brain Injury (MTBI) in rat. METHODS: A closed diffuse brain injury model was successfully produced in rat by hit the parietal bone with a spring-droved steel stick. The auditory brainstem response evoked by click at 50Hz stimulating frequency were recorded at pre-trauma, 15 min and 1, 3, 6, 12 h and 1, 2, 4, 7, 10, 14, 21 d after brain injury. The pathological changes of brain were observed under light microscope and the brain edema was detected by wet weight/dry weight rations. RESULTS: The I-V, III-V of BAEP wave inter peak latency (IPL) in MTBI group increased immediately in 15 minutes after injury. The III, V wave peak latency (PL) and I-V, III-V wave IPL became longer than the pre-trauma level in 6, 12 h post-injury (P<0.05). The III, V wave PL and I - III, I - V, III - V wave IPL became longer than the pre-trauma level in 1, 2 d after injury (P < 0.001), the BAEP retuned to normal level in 14 d after brain injury. At 15 minutes after injury, the water content in brain increased and met its peak in 1 d, decreased gradually in 4 d, then decreased slowly and returned to normal level in 10 d after injury. CONCLUSION: The regular changes of BAEP could be an objective tool for evaluating hearing dysfunction after closed mild diffuse traumatic brain injury.

Animals↗
PubMed2006

Generation and characterization of rabbit embryonic stem cells.

We described the derivation of four stable pluripotent rabbit embryonic stem cell (ESC) lines, one (RF) from blastocysts fertilized in vivo and cultured in vitro and three (RP01, RP02, and RP03) from parthenogenetic blastocysts. These ESC lines have been cultivated for extended periods (RF >1 year, RP01 >8 months, RP02 >8 months, and RP03 >6 months) in vitro while maintaining expression of pluripotent ESC markers and a normal XY or XX karyotype. The ESCs from all lines expressed alkaline phosphatase, transcription factor Oct-4, stage-specific embryonic antigens (SSEA-1, SSEA-3, and SSEA-4), and the tumor-related antigens (TRA-1-60 and TRA-1-81). Similar to human and mouse ESCs, rabbit ESCs expressed pluripotency (Oct-4, Nanog, SOX2, and UTF-1) and signaling pathway genes (fibroblast growth factor, WNT, and transforming growth factor pathway). Morphologically, rabbit ESCs resembled primate ESCs, whereas their proliferation characteristics were more like those seen in mouse ESCs. Rabbit ESCs were induced to differentiate into many cell types in vitro and formed teratomas with derivatives of the three major germ layers in vivo when injected into severe combined immunodeficient mice. Our results showed that pluripotent, stable ESC lines could be derived from fertilized and parthenote-derived rabbit embryos.

Animals↗
PubMed2006

Genes encoding small heat shock proteins of the silkworm, Bombyx mori.

Small heat shock protein (sHSP) is a family of ubiquitous polypeptides involved in a variety of physiological phenomena. From the silkworm, Bombyx mori, we isolated and sequenced the following cDNAs encoding sHSPs: shsp19.9, shsp20.1, shsp20.4, shsp20.8, shsp21.4, and shsp23.7. shsp21.4 was nearly twice as large in size as other shsps. The deduced amino acid sequence of sHSP21.4 was similar to that of Drosophila melanogaster CG14207-PA. Other sHSPs were highly similar to each other and, in a phylogenetic tree, formed a cluster including Plodia interpunctella alphaCP25. It was speculated that shsp21.4 has at least one intron in genome while other shsps do not. The transcripts of all shsps were subtle, but were constitutively detected in various tissues. Heat shock triggered a substantial increase in the transcripts other than shsp21.4. The B. mori sHSPs are perhaps classified into at least two groups: sHSP21.4 and others.

Animals↗
PubMed2006

Protective effects of transcription factor HESR1 on retinal vasculature.

HESR1 is a basic helix-loop-helix transcription factors regulated by the Notch signaling pathway in vertebrate and Drosophila embryos, and is related to the HES/Hairy/E (sp1) family. HESR1 is a downstream target of Notch in endothelial cells and could be an effector of Notch signaling in these cells. HESR1 is necessary for the induction of a tubular network and for continued maintenance of mature and quiescent blood vessels. To examine the role of HESR1 in retinal neovascularization, we transfected retinal vascular endothelial cells (HRCECs) with the HESR1 gene and studied its effects on the expression of angiogenic factors, on the proliferation and migration of endothelial cells, and on the formation of tube-like structures (TLSs). Overexpression of HESR1 downregulated VEGFR-2 expression, upregulated occludin expression, inhibited the migration and proliferation of HRCECs, and inhibited the formation of TLSs. Thus, HESR1 plays a key role in the finely tuned network of molecules involved in the regulation of retinal vascular homeostasis. HESR1 seems to inhibit the vessel-promoting effects of VEGF, shift endothelial cells from a proliferative state to a quiescent state, and restore normal vessel structures. Expression of the HESR1 gene in retinal vascular endothelial cells may protect retinal blood vessels and may be useful in the treatment of diseases involving damage to the retinal vasculature, including diabetic retinopathy, age-related macular degeneration, and retinal vein occlusion.

Adult↗
PubMed2006

Highly spin-polarized field emissions induced by quantum size effects in ultrathin films of Fe on W(001).

Spin-polarized field emissions from Fe pseudomorphic ultrathin films on W(001) surfaces are studied by density functional calculations. We found that nearly completely spin-polarized field emission currents can be realized in two and four Fe layers on W(001) and that these systems have the additional advantages of thermal stability and low work functions. The unusually high spin polarizations of the field emission current is traced to the Fe film's quantum size effects leading to spin-polarized quantum well states and surface resonance states.

Journal Article↗
PubMed2006

[The use of minimally invasive injectable graft and internal fixation in tibial plateau fractures].

OBJECTIVE: To value the use of an injectable minimally invasive calcium sulfate cement for displaced tibial plateau fractures. METHODS: Thirteen patients with lateral tibial plateau fractures treated with internal fixation and bone grafting were matched with 13 patients treated using internal fixation and an injectable calcium sulfate cement. The clinical data were retrospectively analyzed. All patients were followed up for a minimum of one year. The peri-operative complication, quality of reduction, maintenance of reduction, function assessment and development of post-traumatic osteoarthritis was compared in both groups. RESULTS: Ten patients in the internal fixation and bone graft group had excellent anatomical reductions as judged on immediate post-operative radiographs but some loss of reduction on follow-up at one year was observed in 8 of the 13 (61%) cases. Twelve patients from the MIIG group had an excellent reduction on immediate post-operative radiographs but 3 (23%)demonstrated some loss of reduction of the plateau at one year follow-up (P < 0.05). CONCLUSIONS: The use of MIIG and internal fixation is associated with more favourable clinical results than conventional treatment with internal fixation and bone grafting for lateral tibial plateau fractures.

Adult↗
PubMed2006

Immunogenicity and protective efficacy of recombinant pseudorabies virus expressing the two major membrane-associated proteins of porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection still remains today as the most significant health threat to swine and poses a challenge to current vaccination strategies. To develop a new generation of vaccine against PRRSV, a live attenuated pseudorabies virus (PRV) was used as vaccine vector to express the two major membrane-associated proteins (GP5 or M) of PRRSV in various forms. Four PRV recombinants, rPRV-GP5 (expressing native GP5), rPRV-GP5m (expressing GP5m, a modified GP5), rPRV-GP5-M (co-expressing GP5 and M proteins), rPRV-GP5m-M (co-expressing GP5m and M proteins) were generated. Mouse immunized with all these recombinants developed comparable PRV-specific humoral immune responses and provided complete protection against a lethal PRV challenge. However, the highest level of PRRSV-specific neutralizing antibodies and lymphocyte proliferative responses was observed in mice immunized with rPRV-GP5m-M. The immunogenicity and protective efficiency of rPRV-GP5m-M were further evaluated in the piglets. Compared to commercial PRRSV killed vaccine, detectable PRRSV-specific neutralizing antibody and higher lymphocyte proliferative responses could be developed in piglets immunized with rPRV-GP5m-M before virus challenge. Furthermore, more efficient protection against a PRRSV challenge was obtained in piglets immunized with rPRV-GP5m-M, as showed by the balanced body-temperature fluctuation, shorter-term viremia, lower proportion of virus load in nasal and oropharyngeal scrapings and tissues, and milder lung lesions. These data indicate that the recombinant rPRV-GP5m-M is a promising candidate bivalent vaccine against both PRV and PRRSV infection.

Animals↗
PubMed2006

TiO2 surface modification and characterization with nanosized PbS in dye-sensitized solar cells.

The nanoporous TiO2 films utilized in dye-sensitized solar cells (DSSCs) possess a large surface-to-volume ratio, which facilitates the adsorption of sensitizing dye and the recombination due to the high density of surface traps. In this paper, nanosized PbS was fabricated on the TiO2 films. The components of the modified TiO2 film were studied by X-ray diffraction (XRD) and electron probe microanalysis (EPMA), while the structure of the film was characterized with BET physisorption and high-resolution scanning electron microscopy (HRSEM). The results showed that the PbS particles were 2-3 nm and discrete on the surface of TiO2. Diffusion photovoltage (PV) spectroscopy was employed to study the charge separation and diffusion processes inside modified and unmodified TiO2 films. The diffusion PV signals revealed that the traps on the surface of TiO2 were extremely reduced due to the presence of PbS. The results of transient photovoltage and back I-V characteristics showed that the back reaction, that is, the recombination due to the reaction between an electron on TiO2 and the hole-transporting media, was retarded significantly.

Journal Article↗
PubMed2006

Trophic factors counteract elevated FGF-2-induced inhibition of adult neurogenesis.

The dentate gyrus of adult mammalian brain contains neural progenitor cells with self-renewal and multi-lineage potential. The lineage and maturation of the neural progenitors are determined by the composition and levels of the trophic factors in their microenvironment. In Alzheimer disease (AD) brain, especially the hippocampus, the level of basic fibroblast growth factor (FGF-2) is markedly elevated. Here we show that elevated FGF-2 enhances the division and nestin levels of cultured adult rat hippocampal progenitors but impairs neuronal lineage determination and maturation of these cells in culture. The trophic factors ciliary neurotrophic factor (CNTF), glial-derived neurotrophic factor (GDNF), and insulin-like growth factors-1 and -2 (IGF-1, IGF-2) as well as an Alzheimer peptidergic drug, Cerebrolysin((R)) (CL), in which we found these neurotrophic activities, counteract the effect of FGF-2 in inducing neuronal lineage (early neurogenesis). Whereas CNTF is the most active of the neurotrophic factors studied in promoting neurogenesis, CL, probably because of a combined effect of these factors, induces similar changes but without inhibiting cell proliferation. These findings suggest that CNTF, GDNF, IGF-1, and IGF-2 are promising therapeutic targets for AD and other diseases in which neurogenesis is probably inhibited.

Amino Acids↗