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Fei Lu

Publications and source records attributed to Fei Lu.

At least 19 recordsLinked to original sources
PubMed2026

Emergence of two novel HIV-1 Circulating Recombinant Forms (CRF190_0708 and CRF191_0708): molecular characterization and clinical insights from a five-year study in Yunnan, China.

BACKGROUND: To characterize HIV-1 molecular epidemiology and identify novel circulating recombinant forms (CRFs) among antiretroviral therapy (ART)-naïve heterosexuals in Yunnan, China, and evaluate their clinical impact. METHODS: This study examined 636 HIV-1 pol sequences to analyze genetic diversity, pretreatment drug resistance (PDR), and transmission networks. Near full-length genomes were obtained to identify and characterize novel recombinants, with their evolutionary history inferred by Bayesian analysis. Co-receptor tropism was predicted, and the five-year clinical outcomes (including immune reconstitution and virologic response) of patients infected with the novel CRFs were compared. RESULTS: The most prevalent type identified was CRF08_BC, accounting for 50.16% of cases. The prevalence of drug resistance was 5.97% (38/636), with the K103N mutation being the most common. An analysis of transmission networks revealed that 52.2% (272/521) of clusters were associated with CRF07_BC and CRF08_BC. Two novel second-generation CRFs were identified: CRF190_0708, with an estimated time to the most recent common ancestor (tMRCA) of 1998.9, and CRF191_0708, with a more recent tMRCA ranging from 2009.5 to 2011.6. During the five-year follow-up period, viral rebound was observed in 7 patients in the CRF190_0708 group and in 1 patient in the CRF191_0708 group. Drug-resistance mutations (M184V and K103N) were detected in a subset of rebound cases in the CRF190_0708 group. CONCLUSIONS: This study identifies two novel HIV-1 recombinants, CRF190_0708 and CRF191_0708, highlighting ongoing viral evolution in Yunnan. Preliminary findings suggest possible clinical differences, warranting further investigation. Continued molecular surveillance is needed. TRIAL REGISTRATION: The clinical study was registered at ClinicalTrials.gov under the identifier NCT03852849. The date of registration was March 22, 2019.

Adult↗
PubMed2025

Genome-wide association study reveals that TaODORANT1 negatively contributes to thousand grain weight by affecting starch synthesis in wheat.

Thousand grain weight (TGW) is one of the most important factors that control grain weight and crop yield. To date, dozens of wheat genes related to TGW have been isolated; however, the underlying molecular mechanisms governing grain development in wheat (Triticum aestivum) remain largely unknown. Benefiting from whole-genome resequencing and genome-wide association study, we identified an R2R3-type myeloblastosis (MYB) transcription factor, TaODORANT1, which was tightly associated with TGW. TaODORANT1 was specifically and highly expressed during the wheat grain developing stage. Knockout of TaODORANT1 led to an increase in TGW and starch content, as well as affected the expression of starch synthesis-related genes. Loss of function of TaODORANT1 altered the molecular structure and physiochemical properties of grain starch. Haplotype analysis showed that favorable Hap IV of TaODORANT1-A and favorable Hap I of TaODORANT1-B were significantly associated with the production of larger grains and higher TGW, respectively. Moreover, TaODORANT1 was a crucial targeted gene continuously selected in wheat domestication and breeding, and its orthologous genes might have retained similar functions in response to grain development. Our results highlight the importance of TaODORANT1 in affecting TGW, presenting potential targets for improving yield in wheat.

Triticum↗
PubMed2006

Propeller-like multicomponent microstructures: Self-assemblies of nanoparticles of poly(vinyl alcohol)-coated Ag and/or Cu2O.

Novel propeller-like multicomponent microstructures, which are actually self-assemblies of nanoparticles of poly(vinyl alcohol) (PVA)-coated Ag and/or Cu2O, were synthesized in aqueous solution of amphiphilic polyvinylacetone (PVKA) (ketalization degree D(H) = 0.549), via one-step in situ reduction of Ag+ and Cu2+ under gamma-ray irradiation, utilizing the low hydrolysis rate of PVKA in the dilute acidic solution. Herein, PVA chains are obtained from hydrolyzed PVKA. The reaction mechanism and the formation mechanism are proposed. The room temperature photoluminescence spectrum has also been applied to explore the optical property.

Copper↗
PubMed2006

Significant positive correlation between the recombination rate and GC content in the human pseudoautosomal region.

This paper establishes that recombination drives the evolution of GC content in a significant way. Because the human P-arm pseudoautosomal region (PAR1) has been shown to have a high recombination rate, at least 20-fold more frequent than the genomic average of approximately 1 cM/Mb, this region provides an ideal system to study the role of recombination in the evolution of base composition. Nine non-coding regions of PAR1 are analyzed in this study. We have observed a highly significant positive correlation between the recombination rate and GC content (rho = 0.837, p < or = 0.005). Five regions that lie in the distal part of PAR1 are shown to be significantly higher than genomic average divergence. By comparing the intra- and inter-specific AT->GC -GC->AT ratios, we have detected no fixation bias toward GC alleles except for L254915, which has excessive AT-->GC changes in the human lineage. Thus, we conclude that the high GC content of the PAR1 genes better fits the biased gene conversion (BGC) model.

Animals↗
PubMed2006

Study on the interaction of bovine serum albumin with acid cyanine 5R and its application in analysis.

A supramolecular complex of bovine serum albumin (BSA) with acid cyanine 5R (AC 5R, C.I. acid blue 113, C.I.: 26360) has been shown to form in Tris-HCl buffer solution (pH 7.42) by linear sweep voltammetry (LSV), fluorimetry, and spectrophotometry. The binding ratio and binding constant of BSA with AC 5R have been detected by LSV and fluorimetry. The binding mechanism is also preliminarily discussed. In Tris-HCl buffer solution (pH 7.42), AC 5R can easily be reduced on the mercury electrode, and it has a well-defined LSV peak current (Ip) and peak potential (Ep) at -0.65 V (vs. SCE). In the presence of BSA, the Ip of AC 5R decreases, and the peak potential (Ep) shifts to a more positive potential. The decrease of the second-order derivative of reductive peak current (deltaIp'') of AC 5R is proportional to the logarithm of BSA concentration in the range of 1.54 x 10(-8) mol x L(-1)-1.54 x 10(-5) mol x L(-1) (r = 0.9931-0.9977). The limit of detection of BSA is 9.0 x 10(-9) mol x L(-1). The relative standard deviation is 1.83% (n = 10), and the standard recovery is 97.5%-104.8%. This method can be used to determine BSA concentration on the basis of the interaction of BSA with AC 5R.

Animals↗
PubMed2006

[Comparison of effects of low-dose dopamine and dobutamine in patients with nonoliguric renal failure].

OBJECTIVE: To investigate the effects of low-dose dopamine and dobutamine on renal functioning patients with nonoliguric renal failure. METHODS: Twenty-nine hemodynamically stable patients with nonoliguric renal failure were enrolled to this study group. Each patient was given 5% glucose (control), dopamine or dobutamine in random order by means of an injection pump every 4 hours. The change in urine output, fractional excretion of sodium (FeNa) and creatinine clearance rate (CCr) were determined. RESULTS: Compared with control, urine volume, FeNa, and CCr were increased significantly after administration of dopamine, or dobutamine. Compared with dobutamine, dopamine could increase the urine output and the FeNa markedly, but there was no difference in CCr increase between dopamine and dobutamine. CONCLUSION: Dopamine or dobutamine treatment could significantly increase the urine output, FeNa, and CCr in patients with nonoliguric renal failure. Dopamine infusion markedly increases urine output and the FeNa, but there is no significantly difference in CCr between dopamine and dobutamine treatment.

Adult↗
PubMed2006

Electroanalytical method for TPPS4, the interaction of TPPS4 with BSA and the influence of CDs on it by fluorescence spectroscopy.

AIM: To establish a simple, rapid and accurate electroanalytical method for water soluble porphyrin meso-tetrakis-(4-sulfonatophenyl) porphyrin (TPPS4); to clarify the reaction between water soluble porphyrins and bovine serum albumin (BSA); and to determine the interaction of TPPS4 with BSA in the absence of presence of cyclodextrins (CDs), separately. METHODS: Three methods including LSV, UV spectroscopy and fluorescence spectroscopy had been employed to the relevant experiments. The way of employing three methods at the same time could make the experiment results more reliable. RESULTS: In the supporting electrolyte of NaH2 PO4-Na2 HPO4 (pH 7.18), a sensitive reduction peak of TPPS4 was found by linear sweep voltammetry (LSV), the peak potential (Ep) was -0.70 V (vs SCE). The relationship between the second derivative peak of LSV (ip") and the concentration of TPPS4 was linear from 1.0 x 10(-7) mol x L(-1) to 1.0 x 10(-5) mol x L(-1), the square of correlation coefficients (r2) were 0.998 3 and 0.999 3, respectively. The relative standard deviation (RSD) was 0.56% (n = 5). The mean recovery of TPPS4 was 99.59%. In NH4Cl-NH3 x H2O buffers (pH 9.05), it was proved that BSA and TPPS4 could interact with each other and form 1 : 1 TPPS4-BSA supramolecular system. Moreover, the interaction between TPPS4 and BSA had been investigated by adding cyclodextrins (CDs). The interaction of TPPS4 with BSA was facilitated both by hydroxypropyl-beta-CD (HP-beta-CD) and sulforbutylether-beta-CD (SBE-beta-CD). CONCLUSION: An electroanalytical method for TPPS4 has been established by LSV. The porphyrin drugs included by CDs could react with protein existing inside the human body easier. The consequences of this article also show that CDs will play important role in controlling and releasing the porphyrin drugs.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed2006

[Applied anatomic study on the repair of the facial nerve defect by the anastomosis of the facial nerve with the phrenic nerve].

OBJECTIVE: To explore of the anatomic basis of the anastomosis of the facial nerve with the phrenic nerve. METHOD: Bilateral microsurgical dissection was performed on eleven human cadavers fixed with formalin. The following length data were measured with calipers: the distance between the bifurcation of the facial nerve trunk and the phrenic nerve root, the useful length of the facial nerve trunk and the phrenic nerve, and the distance between the overlapped nerve ends. RESULT: The length from the root of the the phrenic nerve to the level of the subclavian vein was (7.2 +/- 1.6) cm. The length from the root of the phrenic nerve to the bifurcation of the facial nerve trunk was (7.23 +/- 0.9) cm. The length from the bifurcation of the facial nerve trunk to the level below the horizontal semicircular canal was 2.7-3.5 cm, 1.0-1.5 cm longer than that cut below the level of the stylomastoid foramen. The cutting nerve ends were placed side by side. The distance between the overlapped nerve ends was 0.4-1.8 cm. CONCLUSION: In 20 specimens the tension-free anastomosis of the facial nerve with the phrenic nerve that cut in the subclavian vein level can be achieved, in 2 specimens the tension-free anastomosis can not be achieved.

Adult↗
PubMed2006

[Comparative study on recruitment maneuvers in acute respiratory distress syndrome with pulmonary and extrapulmonary origin].

OBJECTIVE: To study the effects of lung recruitment maneuvers (RM) in acute respiratory distress syndrome (ARDS) with pulmonary and extrapulmonary origin (ARDSp/ARDSexp). METHODS: Thirty-seven ARDS patients with a forced expiratory volume were selected (16 with ARDSp, 21 with ARDSexp). Without using any sedative and neuromuscular blocking agents, with continuous positive airway pressure (CPAP) up to 30 cm H(2)O (1 cm H(2)O=0.098 kPa), the patients were asked to hold the breath for 30 seconds, and then CPAP was lowered to the level of that before the treatment within 5-10 seconds. RESULTS: Compared with the state before recruitment, changes in heart rate (HR) were not obvious in two groups during RM, mean arterial pressure was elevated evidently after 2 minutes in two groups (both P<0.05), and central venous pressure (CVP) rose after 30 seconds in two groups (both P<0.05). Peak inspiratory pressure, platform pressure and mean airway pressure increased clearly after 30 seconds (all P<0.05), and pulmonary compliance decreased obviously 30 seconds after re-inflation recruitment in two groups (both P<0.05), and increased obviously in ARDSexp group 5, 15, 30 minutes after recruitment (all P<0.05). In the group with ARDSp oxygenation index (OI) changed distinctly 10, 30 minutes and 1 hour after recruitment compared with the state before recruitment (all P<0.05). In patients with ARDSexp OI was significantly improved 10 minutes, 30 minutes, 1 hour, 2 hours after RM. CONCLUSION: In ARDSexp, with pulmonary interstitial edema as the main pathology, responded better to RM than ARDSp with pulmonary consolidation.

Adult↗
PubMed2005

Impact of upgrade to cardiac resynchronization therapy on ventricular arrhythmia frequency in patients with implantable cardioverter-defibrillators.

OBJECTIVES: This study compared cardiac resynchronization therapy's (CRT) impact on ventricular tachyarrhythmia susceptibility in patients who, due to worsening heart failure (HF) symptoms, underwent a replacement of a conventional implantable cardioverter-defibrillator (ICD) with a CRT-ICD. BACKGROUND: Cardiac resynchronization therapy is an effective addition to conventional treatment of HF in many patients with left ventricular systolic dysfunction. However, whether CRT-induced improvements in HF status also reduce susceptibility to life-threatening arrhythmias is less certain. METHODS: Clinical and ICD electrogram data were evaluated in 18 consecutive ICD patients who underwent an upgrade to CRT-ICD. Pharmacologic HF therapy was not altered during follow-up. The definition of ventricular tachycardia (VT) and ventricular fibrillation (VF) for each patient was as determined by device programming. Statistical comparisons used paired t tests. RESULTS: Findings were recorded during two time periods: 47 +/- 21 months (range 24 to 70 months) before and 14 +/- 2 months (range 9 to 18 months) after CRT upgrade. At time of upgrade, patient age was 69 +/- 11 years and ejection fraction was 21 +/- 8%. Before CRT the frequency of VT, VF, and appropriate ICD shocks was 0.31 +/- 1.23, 0.047 +/- 0.083, and 0.048 +/- 0.085 episodes/month/patient, respectively. After CRT-ICD, VT and VF arrhythmia burdens and frequency of shocks were respectively 0.13 +/- 0.56, 0.001 +/- 0.004, and 0.003 +/- 0.016 episodes/month/patient (p = 0.59, 0.03, and 0.05 vs. pre-CRT). CONCLUSIONS: Arrhythmia frequency and number of appropriate ICD treatments were reduced after upgrade to CRT-ICD for HF treatment. Thus, apart from hemodynamic benefits, CRT may also ameliorate ventricular tachyarrhythmia susceptibility in HF patients.

Aged↗
PubMed2005

Comparison of ventricular arrhythmia frequency in patients with ischemic cardiomyopathy versus nonischemic cardiomyopathy treated with implantable cardioverter defibrillators.

Implantable cardioverter defibrillators have been shown to provide similar survival benefits for patients who have left ventricular dysfunction due to ischemic heart disease and for subsets of patients who have nonischemic cardiomyopathy. Findings in this study extend these observations by showing that patients who have ischemic or nonischemic heart disease and receive implantable cardioverter defibrillators not only have comparable mortality rates but also similar tachyarrhythmia frequencies during follow-up; further, mortality and tachyarrhythmia outcomes are independent of initial arrhythmia indication.

Adult↗
PubMed2005

Generation of broadband femtosecond visible pulses in dispersion-micromanaged holey fibers.

Submillimeter-scale dispersion micromanagement (DMM) is used to generate coherent and stable femtosecond visible pulses in holey fibers as short as 10 mm. The longitudinal variation of the phase-matching conditions for Cerenkov radiation and four-wave mixing explains the results well. We have converted up to 20% of the total input energy to a low-noise solitary wave with a bandwidth up to 50 nm in the range 385-625 nm by using holey fibers with various DMM designs.

Journal Article↗
PubMed2005

Broadly tunable femtosecond parametric oscillator using a photonic crystal fiber.

Pulses as short as 460 fs and a tuning range as wide as 200 nm around 1 microm have been achieved from a photonic-crystal-fiber-based parametric oscillator. The ring cavity with only 65 cm of photonic crystal fiber is synchronously pumped with a tunable passively mode-locked Yb-doped fiber laser. Widely extended tunability is achieved by using the modulation instability gain in normal dispersion as the result of high-order dispersion in the photonic crystal fiber.

Journal Article↗
PubMed2005

The crystal structure of human adenylate kinase 6: An adenylate kinase localized to the cell nucleus.

Adenylate kinases (AKs) play important roles in nucleotide metabolism in all organisms and in cellular energetics by means of phosphotransfer networks in eukaryotes. The crystal structure of a human AK named AK6 was determined by in-house sulfur single-wavelength anomalous dispersion phasing methods and refined to 2.0-A resolution with a free R factor of 21.8%. Sequence analyses revealed that human AK6 belongs to a distinct subfamily of AKs present in all eukaryotic organisms sequenced so far. Enzymatic assays show that human AK6 has properties similar with other AKs, particularly with AK5. Fluorescence microscopy showed that human AK6 is localized predominantly to the nucleus of HeLa cells. The identification of a nuclear-localized AK sheds light on nucleotide metabolism in the nucleus and the energetic communication between mitochondria and nucleus by means of phosphotransfer networks.

Active Transport, Cell Nucleus↗
PubMed2005

Effect of cough on heart rate and blood pressure in patients with "cough syncope".

BACKGROUND: "Cough syncope" is uncommon, and its mechanism remains controversial. OBJECTIVES: This study evaluated susceptibility to cough-triggered neural reflex hypotension-bradycardia among cough syncope patients. We hypothesized that individuals with cough syncope would manifest not only more profound cough-triggered hypotension than do other fainters but also an inappropriate chronotropic response accompanying cough-induced hypotension, thereby supporting the notion that a neural reflex hypotension-bradycardia contributes to the condition. METHODS/RESULTS: Three patient groups were studied. Group 1 patients (n = 9) had "cough syncope." The remaining patients had recurrent faints of other causes: group 2 (n = 13) had a positive head-up tilt test, and group 3 (n = 18) had a negative tilt test. With cough, group 1 patients exhibited a greater drop in systolic pressure (-51 +/- 19.3 mmHg) than did either group 2 (-23 +/- 11.1 mmHg, P < .04) or group 3 patients (-28 +/- 12.4 mmHg, P < .05). Recovery time to normalization of systolic pressure was greater in group 1 (25 +/- 9.1 seconds) than in group 2 or 3 (8 +/- 2.7 seconds and 9 +/- 6.1 seconds, respectively, both P < .01 vs group 1). The expected positive chronotropic response accompanying cough-induced hypotension was diminished in group 1 patients (0.16 +/- 0.21 bpm/mmHg) compared with that in either group 2 (0.74 +/- 0.60 bpm/mmHg, P < .05 vs group 1) or group 3 (0.33 +/- 0.15 bpm/mmHg, P = .06 vs group 1). CONCLUSION: Cough syncope patients not only exhibit more pronounced hypotension in response to cough than other fainters, but they also manifest an inappropriate cough-triggered blood pressure-heart rate relationship. These findings argue in favor of the importance of a neurally mediated reflex contribution to symptomatic hypotension in cough syncope.

Aged↗
PubMed2005

[Spectral study on intermolecular coupling interaction and relation to microstructure in polyester/inorganic hybrid materials].

The coupling form of the polymeric-inorganic component and the relation between intermolecular special hydrogen bonding interaction and the microstructure of crystallizable polymer, as well as micro-phase separation scale in non-covalently coupled poly (epsilon-caprolactone) (PCL)/silica (SiO2) hybrid materials were investigated by means of Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The results show that the coupling form between PCL and SiO2 mainly depend on a strong intermolecular hydrogen bonding interaction in the hybrid system. The hydrogen bonding strength increases with increasing TEOS content, while the crystallization of PCL decreases, and the optical transparency of hybrid materials increases. In addition, it affects the scale of micro-phase separation in hybrid materials.

Calorimetry, Differential Scanning↗
PubMed2004

Comparison of catecholamine response during tilt-table-induced vasovagal syncope in patients <35 to those >65 years of age.

This study compared alterations in arterial catecholamine concentrations associated with tilt-induced vasovagal syncope that differed in older (>65 years) and younger patients (<35 years). Older patients with tilt-positive tests tended to exhibit higher baseline epinephrine (E) concentrations and lesser E surge before development of syncope than younger patients (<35 years), whereas both groups manifested comparable norepinephrine (NE) responsiveness.

Adult↗