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Xiaofei Zhang

Publications and source records attributed to Xiaofei Zhang.

10 recordsLinked to original sources
PubMed2024

Comprehensive Proteomic Analysis Reveals Distinct Features and a Diagnostic Biomarker Panel for Early Pregnancy Loss in Histological Subtypes.

Early pregnancy loss (EPL) is a common event in human reproduction and is classified into histological subtypes such as hydropic abortion (HA) and hydatidiform moles, including complete hydatidiform moles (CHMs) and partial hydatidiform moles (PHMs). However, accurate diagnosis and improved patient management remain challenging due to high rates of misdiagnosis and diverse prognostic risks. Therefore, diagnostic biomarkers for EPL are urgently needed. Our study aimed to identify biomarkers for EPL through comprehensive proteomic analysis. Ten CHMs, six PHMs, ten HAs, and 10 normal control products of conception were used to obtain a proteomic portrait. Parallel reaction monitoring-targeted proteomic and regression analyses were used to verify and select the diagnostic signatures. Finally, 14 proteins were selected and a panel of diagnostic classifiers (DLK1, SPTB/COL21A1, and SAR1A) was built to represent the CHM, PHM, and normal control groups (area under the receiver operating characteristic curve = 0.900, 0.804/0.885, and 0.991, respectively). This high diagnostic power was further validated in another independent cohort (n = 148) by immunohistochemistry (n = 120) and Western blot analyses (n = 28). The protein SPTB was selected for further biological behavior experiments in vitro. Our data suggest that SPTB maintains trophoblast cell proliferation, angiogenesis, cell motility, and the cytoskeleton network. This study provides a comprehensive proteomic portrait and identifies potential diagnostic biomarkers. These findings enhance our understanding of EPL pathogenesis and offer novel targets for diagnosis and therapeutic interventions.

Humans↗
PubMed2006

Tobacco use and risk of myocardial infarction in 52 countries in the INTERHEART study: a case-control study.

BACKGROUND: Tobacco use is one of the major avoidable causes of cardiovascular diseases. We aimed to assess the risks associated with tobacco use (both smoking and non-smoking) and second hand tobacco smoke (SHS) worldwide. METHODS: We did a standardised case-control study of acute myocardial infarction (AMI) with 27,089 participants in 52 countries (12,461 cases, 14,637 controls). We assessed relation between risk of AMI and current or former smoking, type of tobacco, amount smoked, effect of smokeless tobacco, and exposure to SHS. We controlled for confounders such as differences in lifestyles between smokers and non-smokers. FINDINGS: Current smoking was associated with a greater risk of non-fatal AMI (odds ratio [OR] 2.95, 95% CI 2.77-3.14, p<0.0001) compared with never smoking; risk increased by 5.6% for every additional cigarette smoked. The OR associated with former smoking fell to 1.87 (95% CI 1.55-2.24) within 3 years of quitting. A residual excess risk remained 20 or more years after quitting (1.22, 1.09-1.37). Exclusion of individuals exposed to SHS in the never smoker reference group raised the risk in former smokers by about 10%. Smoking beedies alone (indigenous to South Asia) was associated with increased risk (2.89, 2.11-3.96) similar to that associated with cigarette smoking. Chewing tobacco alone was associated with OR 2.23 (1.41-3.52), and smokers who also chewed tobacco had the highest increase in risk (4.09, 2.98-5.61). SHS was associated with a graded increase in risk related to exposure; OR was 1.24 (1.17-1.32) in individuals who were least exposed (1-7 h per week) and 1.62 (1.45-1.81) in people who were most exposed (>21 h per week). Young male current smokers had the highest population attributable risk (58.3%; 95% CI 55.0-61.6) and older women the lowest (6.2%, 4.1-9.2). Population attributable risk for exposure to SHS for more than 1 h per week in never smokers was 15.4% (12.1-19.3). CONCLUSION: Tobacco use is one of the most important causes of AMI globally, especially in men. All forms of tobacco use, including different types of smoking and chewing tobacco and inhalation of SHS, should be discouraged to prevent cardiovascular diseases.

Age Distribution↗
PubMed2005

Low pilot exposure to pyrethrin during ultra-low-volume (ULV) aerial insecticide application for control of adult mosquitoes.

Pilot exposure to pyrethrin was monitored after 2 aerial applications of a ultra-low-volume (ULV) pyrethrin insecticide for the control of adult mosquitoes. Pyrethrin exposure was estimated by measuring the excretion in urine of a common metabolite, trans-chrysanthemumdicarboxylic acid, of the natural pyrethrin mixture. Pyrethrin exposure estimated by total daily urine volume was well correlated (R2 = 0.8) with exposure estimated by the creatinine-adjusted volume of combined workday urine voids, indicating that a postapplication spot urine sample would be sufficient to measure pyrethrin exposure. Pilot exposure to pyrethrin was very low after both insecticide applications. The highest exposure was found on day 1, with a dose of 2.05 microg pyrethrin equivalents/day or a dosage of 0.03 microg pyrethrin equivalents/kg/day. These exposure rates represent approximately 1/2,800,000th of the low observed adverse effect level and 1/1,000th of the acceptable daily intake for pyrethrin. The aerial application of ULV pyrethrin insecticide for the control of adult mosquitoes does not result in undue exposure to a pilot who is trained and certified to conduct such control operations.

Aircraft↗
PubMed2005

[Spatial-temporal dynamics of landscape fragmentation in North Shannxi Loess Plateau].

The study of landscape fragmentation is an important means to reveal regional ecological processes. By using the remote sensing data of 1987, 1997 and 2002, and the GIS tools, some representative quantitative indices of the landscape spatial structure and landscape fragmentation in North Shannxi Loess Plateau were calculated, aimed to investigate the relationships between landscape ecological structure and landscape pattern in this area. The results showed that cropland contributed most to the extent of landscape fragmentation, but unused land lacked obvious relationship with it. To get large-area images accurately and promptly is very important for monitoring ecological process in regional scale. Moderate-Resolution Imaging Spectroradiometer (MODIS) images in 2003 were used to derive monthly landscape fragmentation information calculated with Local Index of Spatial Associations (LISA) based on Spatial Statistical Analysis (SSA). The analysis of the fragmented landscape types showed that human disturbance had a main contribution to the seasonal landscape fragmentation. Furthermore, with the increasing percentages of cropland and unused land, landscape became more fragmented, while forestland coverage had inverse effects on the fragmentation.

China↗
PubMed2003

Octachlorodipropyl ether (s-2) mosquito coils are inadequately studied for residential use in Asia and illegal in the United States.

Children and their parents in residences are often protected by insecticides from nuisance and disease-bearing mosquitoes. The annual worldwide consumption of the four major types of residential insecticide products--aerosols, mosquito coils, liquid vaporizers, and vaporizing mats--is in the billions of units. Mosquito coils are burned indoors and outdoors in East Asia and to a limited extent in other parts of the world, including the United States. Coils consist of an insecticide/repellant, organic fillers capable of burning with smoldering, binder, and additives such as synergists, dyes, and fungicide. The number of coil users in China is in the millions. In Indonesia alone, an estimated seven billion coils are purchased annually. Coils containing pyrethroid insecticides, particularly d-allethrin, may contain octachlorodipropyl ether (S-2, S-421) as a synergist or active ingredient. Use of those coils likely exposes children and adults to some level of bis(chloromethyl)ether (BCME). BCME is formed from formaldehyde and hydrogen chloride, combustion products formed from the slow smoldering (about 8 hr/coil) of the mosquito coils. Because BCME is an extremely potent lung carcinogen, the nature and extent of prolonged exposures that recur in homes during the mosquito season in tropical regions must be evaluated with respect to health. In a small analytical study, coils purchased in Indonesia and in the United States contained highly variable amounts of S-2. Some coils that contained S-2 were not labeled, making it impossible for consumers to make an informed decision about coil contents. Mosquito coils containing S-2 are unregistered, and their use is illegal in the United States. Indoor air monitoring under conditions that represent conditions of use in tropical settings and epidemiology to assess health impacts of coil use are essential to permit responsible regulatory decisions regarding continuing S-2 use.

Air Pollution, Indoor↗
PubMed2002

Decisive role of fragmentation functions in hard hadron production.

It is demonstrated that the fragmentation functions at large momentum fraction play a key role in hard hadron production from relativistic proton-proton collisions. We find that this region of the fragmentation functions is not strongly constrained by the electron-positron data. This freedom can be used (together with the transverse-momentum distribution of partons) to reproduce hard pion-to-proton ratio data in relativistic proton-proton collisions.

Journal Article↗
PubMed2002

J/psi suppression in nucleus-nucleus collisions.

We propose a model for calculating J/psi suppression in high-energy hadron-nucleus and nucleus-nucleus collisions. We factorized the process into a production of the cc- pairs convoluted with a transition probability into the observed J/psi mesons. As the produced cc- pairs exit the nuclear matter, multiple scattering increases the square of the relative momentum between the c and c- such that some pairs are transmuted into open charm states. With only one parameter, the energy gained by the produced cc- pair per unit length in the nuclear medium, our model can fit all observed J/psi suppression data in hadron-nucleus and nucleus-nucleus collisions.

Journal Article↗
PubMed2002

[Effect of brain extract of hypoxic preconditioned mice on activity of ATP sensitive potassium channel in hippocampal neurons].

OBJECTIVE: To observe the effect of brain extract taken from hypoxic preconditioned mice on activity of ATP sensitive potassium channel (K(ATP)). METHODS: Changes of outward potassium current (Ik) were recorded by whole cell patch clamp in acutely dissociated rat hippocampal neurons prior to and after application of glibenclamide (GLI). the brain extract of hypoxic preconditioned mice. RESULTS: Ik was significantly increased by addition of sodium cyanide (NaCN) (1448-->2381 pA) and the increase was significantly inhibited (2381-->1725 pA) by application of glibenclamide (GLI). Similar increase and decrease were shown when adenosine (ADO) and GLI were added (1399-->2584-->1703 pA). The current was also significantly increased and inhibited, respectively, when brain extract of preconditioned mice who had been exposed to hypoxian 4 times and GLI were applied (1298-->2413-->1713 pA). No significant change was seen when brain extract taken from mice exposed to hypoxia only once was added. CONCLUSION: K(ATP) of hippocampal neurons is activated by ADO-like neuroactive substances in the brain extract of hypoxic preconditioned mice.

Adenosine↗