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Hao Hu

Publications and source records attributed to Hao Hu.

At least 19 recordsLinked to original sources

Priming of CD8+ T cells by peripheral dendritic cells exacerbates tau-mediated neurodegeneration.

Alzheimer's disease and primary tauopathies are marked by changes in adaptive immunity, with increased brain CD8+ T cells correlating with tau pathology severity. However, how peripheral T cells get primed to enter the brain and contribute to tau-mediated neurodegeneration remains unclear. In different disease conditions, conventional type 1 dendritic cells (cDC1s) cross-present antigens to prime CD8+ T cells into effector cells. We show that tauopathy mice lacking cDC1s or antigen cross-presentation are protected from neurodegeneration, with reduced brain CD8+ T cell infiltration and glial activation. The remaining CD8+ T cells exhibit limited clonal expansion, consistent with impaired priming. We further demonstrate that brain-derived antigens are presented in secondary lymphoid tissues, suggesting a site of T cell activation. Together, these findings establish cDC1-dependent peripheral priming as a key driver of CD8+ T cell accumulation in the brain and tau-mediated neurodegeneration.

Journal Article↗

EucaMOD: a comprehensive multi-omics database for functional genomics research and molecular breeding of fast-growing eucalyptus trees.

Eucalyptus, one of the most widely planted plantation tree species globally, is primarily found in tropical and subtropical regions and contributes significantly to economic and social benefits. With advances in sequencing technologies, there is an increasing demand for the systematic analysis of multi-omics data among Eucalyptus species to enhance genetic breeding efforts. Although several early genomic databases have been established for eucalyptus, they have not been updated in a timely manner and lack recent multi-omics data, rendering them insufficient for current research needs. To address this gap, we developed the eucalyptus multi-omics database (EucaMOD, http://eucalyptusggd.net/eucamod), a comprehensive resource for cross-omics studies. In this study, we functionally annotated 45 eucalyptus genomes and structurally annotated 15, conducting comparative genomics and pan-proteomics analyses across all genomes. Additionally, we analyzed eucalyptus transcriptome, epigenome, and variome data through standardized workflows, enabling the in-depth mining and reanalysis of multi-omics datasets. EucaMOD is the most comprehensive multi-omics database for eucalyptus to date and includes data from 45 genomes (39 species), 870 mRNA-seq samples, 17 miRNA-seq samples, 52 epigenomic datasets (histone modifications and transcription factor binding), and genetic variation data from 1219 samples. To support functional genomics and molecular breeding research, the database is organized into the following 11 modules: Home, Species, Genomics, Comparative genomics, Pan-proteomics, Transcriptomics, Epigenetics, Variomics, Tools, Download, and Help. EucaMOD also offers online analysis tools for data mining, providing free public services to aid eucalyptus gene function and genetic engineering studies.

Eucalyptus↗

Direct detection of the formation of V-amylose helix by single molecule force spectroscopy.

An important polysaccharide, amylose crystallizes as a regular single left-handed helix from a propanol, butanol, or iodine solution. However, its solution structure remains elusive because amylose does not form molecular solutions in these solvents, and standard spectroscopic techniques cannot be exploited to determine its structure. Using AFM, we forced individual amylose chains adsorbed to a surface to enter these poor solvents and carried out stretch-release measurements on them in solution. In this manner, we directly captured the formation of individual amylose helices induced by butanol and iodine. With an accuracy approaching that of X-ray diffraction on amylose crystals, we determined that the pitch of the helix in solution is 1.3 angstroms/ring. We also directly measured the force driving the formation of the helix in solution to be 50 pN. SMD simulations in explicit butanol reproduced the AFM-measured force-extension curves and revealed that the long plateau feature is caused by the rupture of O(2)n-O(6)(n+6) and O(3)n-O(6)(n+6) hydrogen bonds and by the unwinding of the helix. We also found that amylose helices formed in iodine solution are more compliant and hysteretic as compared to helices in butanol, which extend/relax reversibly. In iodine solution, the formation of the helix is inhibited by force and limited by the slow kinetics of the amylose-iodine complex. By forcing individual molecules into poor solvents and performing force spectroscopy measurements in solution, our AFM approach uniquely supplements X-ray diffraction and NMR methods for investigating solution conformations of insoluble biopolymers.

Amylose↗

Simulating force-induced conformational transitions in polysaccharides with the SMD replica exchange method.

Conventional steered molecular dynamics (SMD) simulations do not readily reproduce equilibrium conditions of atomic force microscopy (AFM) stretch and release measurements of polysaccharides undergoing force-induced conformational transitions because of the gap between the timescales of computer simulations ( approximately 1 mus) and AFM measurements ( approximately 1 s). To circumvent this limitation, we propose using the replica exchange method (REM) to enhance sampling during SMD simulations. By applying REM SMD to a small polysaccharide system and comparing the results with those from AFM stretching experiments, we demonstrate that REM SMD reproduces the experimental results not only qualitatively but quantitatively, approaching near equilibrium conditions of AFM measurements. As tested in this work, hysteresis and computational time of REM SMD simulations of short polysaccharide chains are significantly reduced as compared to regular SMD simulations, making REM SMD an attractive tool for studying forced-induced conformational transitions of small biopolymer systems.

Computer Simulation↗

[Surgical anatomy of the colic vessels in Chinese and its influence on the operation of esophageal replacement with colon].

OBJECTIVE: To investigate the configuration of colic vessels in Chinese and its influence on the operation of esophageal replacement with colon (ERC). METHODS: The origin, trend, branching, configuration, and distribution of the colic vessels, the intensity of the colic arterial impulse, the integrity of the marginal artery at the splenic flexure and hepatic flexure of colon were observed during the operation of ERC among 582 patients undergoing ERC, 402 males mad 180 females, aged 2 approximately 74, from 22 provinces, municipality, and autonomous regions. RESULTS: The left colic artery (LCA) stemmed from the inferior mesenteric artery (IMA) in 97.3% of the patients, with an absence rate of 0.7%. The middle colic artery (MCA) stemmed from the superior mesenteric artery (SMA) in 77.8% of the patients with an absence rate of 8.2%. Accessory middle colic artery (acMCA), originating from the right colic artery, could be seen in 6.2% of the patients 39.7% of the right colic artery (RCA) stemmed from the SMA by itself, 23.0% of the RMA stemmed together with MCA, and 28.0% of the RCA stemmed together with the ileocolic artery. The absence rate of RCA was 9.8%. The intactness rate of marginal artery was 96.8% at the splenic flexure of colon, and was 88.7% at the hepatic flexure. The Rolan arch was seen in only 7.6% of the patients. CONCLUSION: The configuration of colic vessels in Chinese was basically similar to those of the results of autopsies carried out abroad. The optimal supply artery of colic segment during ERC is LCA, followed by LCA. Attention should be paid to the integrity of marginal arteries and veins in the patients with history of epigastric operation.

Adolescent↗

Crystallization and preliminary crystallographic studies of human septin 1 with site-directed mutations.

Septin 1 is a member of an evolutionarily conserved family of GTP-binding and filament-forming proteins named septins, which function in diverse processes including cytokinasis, vesicle trafficking, apoptosis, remodelling of the cytoskeleton, infection, neurodegeneration and neoplasia. Human septin 1 has been expressed and purified, but suffers from severe aggregation. Studies have shown that septin 1 with site-directed mutations of five serine residues (Ser19, Ser206, Ser307, Ser312 and Ser315) has a much lower degree of aggregation and better structural homogeneity and that the mutations cause only slight perturbations in the secondary structure of septin 1. This septin 1 mutant was crystallized and diffraction data were collected to 2.5 A resolution. The space group is P422, with unit-cell parameters a = b = 106.028, c = 137.852 A.

Crystallization↗

Advanced visualization platform for surgical operating room coordination: distributed video board system.

One of the major challenges for day-of-surgery operating room coordination is accurate and timely situation awareness. Distributed and secure real-time status information is key to addressing these challenges. This article reports on the design and implementation of a passive status monitoring system in a 19-room surgical suite of a major academic medical center. Key design requirements considered included integrated real-time operating room status display, access control, security, and network impact. The system used live operating room video images and patient vital signs obtained through monitors to automatically update events and operating room status. Images were presented on a "need-to-know" basis, and access was controlled by identification badge authorization. The system delivered reliable real-time operating room images and status with acceptable network impact. Operating room status was visualized at 4 separate locations and was used continuously by clinicians and operating room service providers to coordinate operating room activities.

Computer Communication Networks↗

[Effect of aluminum trichloride on dissociated Ca2+ in Hippocampus neuron cell as well as learning and memory].

OBJECTIVE: To investigate the effect of aluminum chloride on dissociated Ca(2+) in hippocampus neuron cells in mice and the relationship to the learning and memory. METHODS: Male ICR mice in the three intoxicated groups were administered with the double distilled water containing AlCl(3) (10, 50, 300 mg.kg(-1).d(-1)) while those in the control group were administered with the double distilled water for 100 days. The methods of behavior toxicology such as Morris swim maze were used for studying the effect of aluminum chloride on the changes of learning and memory in mice. With calcium sensitive fluorescence indicator Fura-2 as the fluorescent probe, the influence of the subchronic exposure to Al on the dissociated Ca(2+) in hippocampus neuron cells was observed. RESULTS: The dissociated Ca(2+) in hippocampus neuron cells in the middle dosage group and the high dosage group [(412.25 +/- 53.20), (467.37 +/- 32.85) times] was lower than those in the control group [(293.91 +/- 32.21) times] respectively (P < 0.01), and correlated positively with the dose and dissociated Ca(2+) (r = 0.861, P < 0.01). Compared with the control group, the latent period was lengthened (P < 0.05) in the middle dosage and the high dosage group. CONCLUSION: The subchronic exposure to AlCl(3) in mice affects the dissociated Ca(2+) in hippocampus neuron cells. The increase of dissociated Ca(2+) in hippocampus neuron cells may be correlated with the disfunction of cognition in the aluminium intoxicated mice.

Aluminum Chloride↗

Dual-topology/dual-coordinate free-energy simulation using QM/MM force field.

We have developed a dual-topology/dual-coordinate free-energy simulation method for use with a QM/MM force field. By combining two parallel processes into one alchemical process, we are able to compute the double free-energy difference (delta deltaF) within a single simulation, which eliminates half of the expensive quantum-mechanical simulation in general. The method has been tested in computing the solvation free-energy differences of several molecular pairs and shows close agreement with experimental results.

Computer Simulation↗

Detoxification of cyanide by woody plants.

Vascular plants possess an enzyme system that detoxifies cyanide by converting it to the amino acid asparagine. This paper examines the potential of three woody plants from the Salicaceae family to degrade cyanide. Pre-rooted trees were grown in carefully designed bioreactors with aqueous solution spiked with potassium cyanide at 23.0 +/- 1 degree C for a maximum of 144 h. Cyanide concentrations ranged from 0.95 to 1.15 CN mg/L. Cyanide in water and in plant tissues was analyzed spectrophotometrically. Results from the investigation indicated that significant reduction of aqueous cyanide was found during the presence of plants in all treatments. Little amounts of applied cyanide were detected in the tissues of plants, mainly in roots and bottom stem. Cyanide remaining in tissues varied with the species of plants, despite similar periods of exposure. The data also indicated that photolysis, hydrolysis, and microbial degradation were not occurring and that volatilization was minimal. In conclusion, transport and metabolism of cyanide in plants is most likely.

Biodegradation, Environmental↗

Crystallization and preliminary X-ray crystallographic studies of human cyclophilin J.

Human cyclophilin J, a new member of the cyclophilin family, has been expressed and crystallized. Diffraction data have been collected to 2.0 A resolution and preliminary crystallographic studies have been completed. The space group of the crystals is P3(1)21, with unit-cell parameters a = b = 40.597, c = 170.732 A, alpha = beta = 90, gamma = 120 degrees.

Cloning, Molecular↗

Relating side-chain mobility in proteins to rotameric transitions: insights from molecular dynamics simulations and NMR.

The dynamic aspect of proteins is fundamental to understanding protein stability and function. One of the goals of NMR studies of side-chain dynamics in proteins is to relate spin relaxation rates to discrete conformational states and the timescales of interconversion between those states. Reported here is a physical analysis of side-chain dynamics that occur on a timescale commensurate with monitoring by 2H spin relaxation within methyl groups. Motivated by observations made from tens-of-nanoseconds long MD simulations on the small protein eglin c in explicit solvent, we propose a simple molecular mechanics-based model for the motions of side-chain methyl groups. By using a Boltzmann distribution within rotamers, and by considering the transitions between different rotamer states, the model semi-quantitatively correlates the population of rotamer states with 'model-free' order parameters typically fitted from NMR relaxation experiments. Two easy-to-use, analytical expressions are given for converting S2 (axis') values (order parameter for C-CH3 bond) into side-chain rotamer populations. These predict that S2 (axis') values below 0.8 result from population of more than one rotameric state. The relations are shown to predict rotameric sampling with reasonable accuracy on the ps-ns timescale for eglin c and are validated for longer timescales on ubiquitin, for which side-chain residual dipolar coupling (RDC) data have been collected.

Carbon↗

The effect of temperature on the rate of cyanide metabolism of two woody plants.

The response of cyanide metabolism rates of two woody plants to changes in temperature is investigated. Detached leaves (1.0 g fresh weight) from weeping willow (Salix babylonica L.) and Chinese elder (Sambucus chinensis Lindl.) were kept in glass vessels with 100ml of aqueous solution spiked with potassium cyanide for a maximum of 28 h. Ten different temperatures were used ranging from 11 degrees C to 32 degrees C. The disappearance of aqueous cyanide was analyzed spectrophotometrically. The cyanide removal rate of Chinese elder was higher than that of weeping willow at all temperatures. The highest cyanide removal rate for Chinese elder was found at 30 degrees C with a value of 12.6 mg CN kg(-1) h(-1), whereas the highest value of the weeping willow was 9.72 mg CN kg(-1) h(-1) at 32 degrees C. The temperature coefficient values, Q10, which are the ratio of removal rates at a 10 degree difference, were determined for Chinese elder and weeping willow to 1.84 and 2.09, respectively, indicating that the cyanide removal rate of weeping willow was much more susceptible to changes in temperature than that of the Chinese elder. In conclusion, changes in temperature have a substantial influence on the removal rate of cyanide by plants.

Biodegradation, Environmental↗

An algorithm for processing vital sign monitoring data to remotely identify operating room occupancy in real-time.

We developed an algorithm for processing networked vital signs (VS) to remotely identify in real-time when a patient enters and leaves a given operating room (OR). The algorithm addresses two types of mismatches between OR occupancy and VS: a patient is in the OR but no VS are available (e.g., patient is being hooked up), and no patient is in the OR but artifactual VS are present (e.g., because of staff handling of sensors). The algorithm was developed with data from 7 consecutive days (122 cases) in a 6 OR trauma center. The algorithm was then tested on data from another 7 consecutive days (98 cases), against patient in- and out-times captured by OR surveillance videos. When pulse oximetry, electrocardiogram, and temperature readings were used, OR occupancy was correctly identified 96% (95% confidence interval [CI] 95%-97%) and OR vacancy >99% of the time. Identified patient in- and out-times were accurate within 4.9 min (CI 4.2-5.7) and 2.8 min (CI 2.3-3.5), respectively, and were not different in accuracy from times reported by staff on OR records. The algorithm's usefulness was demonstrated partly by its continued operational use. We conclude that VS can be processed to accurately report OR occupancy in real-time.

Algorithms↗

Molecular analysis of SLC26A4 gene in a Chinese deafness family.

OBJECTIVE: To identify the pathogenic gene for a non-syndromic hearing loss family. METHODS: Mutation analysis was carried out by polymerase chain reaction and direct sequencing of all exons of SLC26A4 (solute carrier family 26, member 4) gene. RESULTS: Compound heterozygous mutations N392Y and S448X were detected in the proband of the family, heterozygous mutation S448X was detected in the father, heterozygous mutation N392Y was detected in the mother. CONCLUSION: The proband's hearing loss resulted from the compound heterozygous mutations N392Y and S448X for SLC26A4 gene.

Adult↗

[Effect of aluminum chloride on motor activity and species-typical behaviors in mice].

OBJECTIVE: To study the effect of aluminum chloride on motor and species-typical behaviors in mice. METHODS: Male ICR mice were administered with drinking double distilled water only containing AlCl(3) (10, 50, 300 mg x kg(-1) x d(-1)), and control group with drinking double distilled water only for 100 days. Spontaneous activity test, grip strength, beam traversal, tightrope task, food hoarding, and nest construction were used to study the effect of chloride aluminum on motor and species-typical behaviors in mice. RESULTS: The frequencies of spontaneous activity in low dose group, medium dose group and high dose group [(81.53 +/- 8.97), (71.67 +/- 8.37), (66.73 +/- 6.96) times respectively] were lower than that in control [(106.46 +/- 8.21) times] (P < 0.01), and were negatively correlated with doses (r(s) = -0.42, P < 0.01). Grip strength scores in medium dose group (19.19 +/- 1.48) and high dose group (13.36 +/- 1.46) respectively were lower than that in control (24.31 +/- 1.43) (P < 0.05, P < 0.01). Food hoarding was greater in high dose group [96.10 (90.20-99.00) g] than that in control group [84.00 (78.00-90.00) g (P < 0.05)]. The rest of parameters were of no statistical significance. CONCLUSION: Subchronic exposure to AlCl(3) in mice may diminish motor activity and grip strength, but motor coordination was not impaired; alteration in food hoarding suggests damage to hippocampus cell.

Aluminum Chloride↗

[Prenatal diagnosis of prelingual deafness by determination of SLC26A4 gene mutation].

OBJECTIVE: To identify deafness related gene and provide its prenatal diagnosis to avoid deaf fetus delivery. METHODS: DNA was extracted from amniotic cells in a pregnant woman close to 21 weeks' gestation, as well as from peripheral blood cells of the pregnant woman, her husband and their two sons. Screening for GJB2 and SLC26A4 gene mutations was firstly performed in the deafness proband (the first son of the couple), and then it was carried out in the fetus and the rest family members. RESULTS: The first child of the family, i.e., the proband, was homozygous in the IVS7-2A > G mutation of SLC26A4, the parents and the second child were carriers of the same mutation, while the fetus had a wild-type form. CONCLUSION: It is feasible to identify deafness related genes by screening for GJB2 and SLC26A4 mutation, thus providing correct prenatal diagnosis and avoiding deaf delivery of baby.

Adult↗