Biomedical subjects

Wei Peng

Publications and source records attributed to Wei Peng.

At least 19 recordsLinked to original sources

PubMed2026

Evaluation of intravenous sedation in dental implant surgeries: A prospective cohort study.

PURPOSE: This study aimed to evaluate the impact of intravenous sedation on patient-centered outcomes during implant and bone augmentation surgeries. METHOD: A prospective observational cohort study included 40 patients undergoing placement of ≥3 implants, with or without bone augmentation. Patients underwent surgery under either intravenous sedation (n = 20) or local anesthesia alone (n = 20), according to routine clinical decision-making and patient preference. The sedation group received intravenous sedation with a multimodal regimen comprising remimazolam, dexmedetomidine, alfentanil, and low-dose esketamine, whereas the control group received local anesthesia only. Patient-reported outcome measures, hemodynamic parameters (SBP, DBP, HR, SpO2), postoperative pain (0-10 scale), and OHRQoL (OHIP-14) were recorded from baseline through 7 days post-surgery. RESULTS: Intravenous sedation was associated with significantly lower intraoperative pain (0.5 [IQR: 0∼2.75] vs. 3.25 ± 2.40, p = 0.003), anxiety (1 [IQR: 0∼2.75] vs. 4 [IQR: 3∼6], p = 0.001), and experienced discomfort (2 [IQR: 1∼3.75] vs. 4.15 ± 2.16, p = 0.016), and shortened perceived treatment duration (2.90 ± 2.34 vs. 5 [IQR: 4∼5], p = 0.020). Early postoperative pain was lower in the sedation group from Days 1-4 (p = 0.003-0.010). Hemodynamic parameters were more stable under sedation, with lower SBP (116.42 ± 13.32 vs. 144.11 ± 17.42 mmHg, p < 0.001), DBP (73.21 ± 10.28 vs. 82.37 ± 11.03 mmHg, p = 0.012), and HR (71.00 [IQR: 62.50∼79.25] vs. 85.00 ± 10.72 bpm, p = 0.021). OHRQoL scores favored the sedation group in swallowing, diet, malaise, and daily activities, particularly during the first three postoperative days (p=0.006-0.040). CONCLUSION: Intravenous sedation may enhance the patient experience during implant and/or bone augmentation procedures by reducing intraoperative pain and anxiety, improving hemodynamic stability, and promoting better early-postoperative recovery and OHRQoL. These findings suggest that intravenous sedation provides a safe and effective alternative for implant dentistry surgery, particularly for anxious or pain-sensitive individuals.

Humans↗

PubMed2006

Expression, refolding, and characterization of recombinant thrombopoietin/stem cell factor fusion protein in Escherichia coli.

Thrombopoietin/stem cell factor (TPO/SCF) is a novel fusion protein that combines the complementary biological effects of TPO and SCF into a single molecule. In this study, TPO/SCF gene was cloned into pET32a and expressed as a thioredoxin (Trx) fusion protein with a C-terminal 6His-tag in Escherichia coli BL21(DE3) under the control of T7 promoter. Trx-TPO/SCF protein approximately accounted for 20% of the total bacterial proteins and was found to accumulate in inclusion bodies. Inclusion bodies were separated from cellular debris, washed with buffer containing 2 M urea, and solubilized with 8 M urea. The refolding of Trx-TPO/SCF was then carried out by an on-column method. Soluble Trx-TPO/SCF was characterized for its dose-dependent effects on promoting cells proliferation in both TF1 and Mo7e cell lines. rhTPO/SCF was released by thrombin digestion and further purified by Ni(2+) affinity chromatography. Western blot analysis confirmed the identities of Trx-TPO/SCF and rhTPO/SCF.

Blotting, Western↗

PubMed2006

Fiber-optic surface plasmon resonance sensors in the near-infrared spectral region.

The sensitivity of fiber-optic surface plasmon resonance (SPR) sensors was improved by a factor of at least thirteen for aqueous solutions by modifying the tip geometry to allow interrogation of the surface plasmon (SP) band in the near-infrared (NIR) region. This was achieved by tuning the angle at the distal end of the SPR sensor to a dual taper of 71 degrees and 19 degrees . Using a low numerical aperture (NA) fiber-optic sensor, NA = 0.12, is necessary to obtain a functional SPR sensor working in the NIR region. Theoretical simulations using the Maxwell equations demonstrated that even higher enhancement is theoretically possible while maintaining a narrow spectral feature upon the excitation of the SP bands on gold surfaces. The manufacture of the SPR sensors yields good agreement between theoretical simulations and experimental observations. To investigate the properties of these fiber-optic SPR-NIR sensors, sucrose solutions ranging from 0 to 15 x 10(-3) in mole fraction were utilized. The increased sensitivity of the fiber-optic SPR sensors, when used to monitor biomarkers, would yield lower detection limits. The smaller sensing area, compared to planar or other fiber-optic SPR sensors, combined with an improvement of the sensitivity, would yield a dramatic reduction of the absolute amount detected by biosensors.

Biosensing Techniques↗

PubMed2006

[Investigation on epidemiology in 645 cases with sepsis in surgical intensive care unit].

OBJECTIVE: To investigate the epidemiology of sepsis in surgical intensive care unit. METHODS: The clinical data of 645 intensive care unit cases, admitted during January 2003 to December 2004 in Shanghai Integrated Traditional Chinese and Western Medicine Hospital, were analyzed. The incidence and mortality of systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis and septic shock, as well as the relationship between them, and age, sex were studied. The hospital stay time was compared among the patients with sepsis, severe sepsis, septic shock and the patients without sepsis. RESULTS: The incidence of SIRS at the first day and second day in surgical intensive care unit was 63.7% and 49.8% respectively, while 74.3% of the cases developed SIRS in surgical intensive care unit. There was no death in non-SIRS group, while the mortality was 6.26% in SIRS group. The incidences of sepsis, severe sepsis, septic shock were 27.0%, 10.9%, 7.0% respectively, and their mortality was 14.94%, 34.29%, 51.11% respectively. The elderly and the male had more chance to develop sepsis (both P<0.01). The sepsis group stayed longer in surgical intensive care unit than non-sepsis group (P<0.01). CONCLUSION: Sepsis is not uncommon in surgical intensive care unit and elderly and male are more susceptible to develop it and carry a poor prognosis. More attention should be given to sepsis in surgical intensive care unit.

Adolescent↗

PubMed2006

[Predictive value of serum soluble fms-like tyrosine kinase 1 concentration in preeclampsia at second trimester].

OBJECTIVE: To explore the predictive value of serum soluble fms-like tyrosine kinase-1 (sFlt-1) and vascular endothelia growth factor (VEGF) levels in preeclampsia at second trimester. METHODS: Serum sFlt-1, VEGF concentrations were determined in 172 initial normal pregnant women at 26 - 28 gestation week. The outcomes of pregnancies were followed. In a cohort of 172 pregnant women, 16 cases of preeclampsia were developed (preeclampsia group), and 156 cases were with no complication (control group). RESULTS: The serum levels of sFlt-1 in preeclampsia group (11.4 +/- 6.2) microg/L were significantly higher than that in control group (4.5 +/- 2.1) microg/L (P < 0.01). The serum levels of sFlt-1 in precelampsia women with the onset before 32 gestation week and fetal growth retardation, (14.0 +/- 6.8) microg/L, (14.4 +/- 6.7) microg/L were significantly higher than that in women with the onset after 32 gestation week and with no fetal growth retardation (9.0 +/- 4.1) microg/L, (8.9 +/- 4.0) microg/L, respectively (P < 0.05). There was no significant difference in the serum levels of VEGF between preeclampsia group and control group. A sFlt-1 cutoff value of 8.75 microg/L at 26 - 28 gestation week yielded a sensitivity of 87.5%, specificity of 97.4%, positive predictive value of 80.0%, negative predictive value of 88.5%, respectively, for subsequent onset of preeclampsia. CONCLUSION: Maternal serum sFlt-1 concentration at second trimester can be used as an early predictive marker of preeclampsia.

Adult↗

PubMed2006

[Expression and significance of soluble fms-like tyrosine kinase 1 in preeclampsia placenta].

OBJECTIVE: To investigate the expression and significance of serum soluble fms-like tyrosine kinase 1 (sFlt-1) in preeclampsia placenta. METHODS: Immunohistochemistry and semi-quantitative RT-PCR were used to investigate the expression of sFlt-1 and sFlt-1 mRNA in placenta of 30 women with preeclampsia (including mild and moderate preeclampsia 11 cases, severe preeclampsia 19 cases) and 45 normal pregnant women (including first trimester pregnancy 18 cases, 2nd trimester pregnancy 12 cases, and 3rd trimester pregnancy 15 cases). The levels of vascular endothelial growth factor (VEGF) and sFlt-1 in serum were detected by enzyme linked immunosorbent assay. RESULTS: (1) The expression of sFlt-1 mRNA was significantly higher in preeclampsia group (0.90 +/- 0.11) compared with the third trimester group (0.80 +/- 0.06; P < 0.01), and was higher in the severe preeclampsia group (0.93 +/- 0.12) than that in the mild group (0.85 +/- 0.05; P < 0.05). (2) The mean density of sFlt-1 in preeclampsia placenta (0.156 +/- 0.008) was significantly higher than that in the third trimester group (0.143 +/- 0.009, P < 0.01), and was higher in the severe group (0.159 +/- 0.008) than in the mild group (0.151 +/- 0.005; P < 0.05). (3) The level of VEGF in serum of the preeclampsia group (19.3 +/- 2.9) ng/L was significantly lower than that of the third trimester group [(30.2 +/- 3.1) ng/L, P < 0.01]. The level of sFlt-1 in serum of the preeclampsia group (30.2 +/- 13.7) microg/L was significantly higher than that of the third trimester group [(7.4 +/- 3.1) microg/L, P < 0.01]. (4) There was significant correlation between the serum level of sFlt-1 and the expression of sFlt-1 mRNA or sFlt-1 in placenta of normal pregnancy group (r = 0.314, P < 0.05; r = 0.439, P < 0.01) and preeclampsia groups (r = 0.372, r = 0.383; P < 0.05). CONCLUSION: Upregulation of sFlt-1mRNA and excess expression of sFlt-1 in placenta may induce higher level of sFlt-1 in serum, which may be involved in the pathophysiological processes of preeclampsia.

Adult↗

PubMed2005

Investigation of dual-channel fiber-optic surface plasmon resonance sensing for biological applications.

A dual-channel fiber-optic sensor based on surface plasmon resonance (SPR) for self-referencing refractive-index measurements has been proposed. Most applications of fiber-optic SPR sensors are designed to measure the refractive index of a liquid or gas sample by measuring the signal from a single surface, the sensitivity and stability of which is easily affected by the fluctuation of external environmental conditions. We have designed a dual-channel fiber-optic surface sensor with two independent SPR signals from two areas of the same probe. A prototype sensor was fabricated and characterized. The preliminary experimental results demonstrate the characteristic responses of both SPR signals from two channels that independently correspond to the refractive index changes in the liquid samples with which they are in contact. The design could be extended to a multichannel sensor with further developments. The experimental results confirmed that one channel can be used as a reference sensor that could compensate for unexpected changes in bulk refraction or temperature and develop this sensor as a practicable high-sensitivity biosensing device.

Journal Article↗

PubMed2005

CD1a-, b-, and c-restricted TCRs recognize both self and foreign antigens.

Individual CD1-restricted T cells can recognize either endogenous or foreign lipid Ags, but the extent to which the same CD1-restricted TCR can react to both self and microbial lipids is unknown. In this study, we have identified CD1a-, CD1b-, and CD1c-restricted T cells from normal human donors that induce cytolysis and secrete copious IFN-gamma in response to self-CD1 expressed on monocyte-derived dendritic cells. Remarkably, microbial Ags presented by CD1 are even more potent agonists for these same T cells. The alphabeta T cell receptors from such clones are diverse and confer specificity for both self-CD1 and foreign lipid Ags. The dual reactivity of these CD1-restricted cells suggests that the capacity for rapid responses to inflammatory stimuli without memory coexists with the capacity for strong Ag-specific responses and the generation of memory in vivo.

Antigens, CD1↗

PubMed2005

Tapered fiber optic surface plasmon resonance sensor for analyses of vapor and liquid phases.

We report a new approach to analyze both vapor and liquid phases by utilizing a tapered fiber optic surface plasmon resonance (SPR) probe. This technique employs a fiber optic SPR probe with a modified geometry to tune the SPR coupling wavelength-angle pair. The observed composite spectrum included two distinct SPR dips associated with surface plasmons excited in the gas and liquid active regions. This sensor is able to detect refractive index changes in both vapor and liquid phases individually by simultaneous monitoring SPR coupling wavelengths from the two sensing surfaces.

Journal Article↗

PubMed2005

Fingerprint quality control of Tianjihuang by high-performance liquid chromatography-photodiode array detection.

A novel, simple and accurate fingerprint method was developed using high-performance liquid chromatography-photodiode array detection (HPLC-DAD) for the quality control of Hypericum japonicum thunb (Tianjihuang), a Chinese herbal medicine used for the treatment of several bacterial diseases, infectious hepatitis, gastrointestinal disorder, internal hemorrhage and tumors. For the first time, the feasibility and advantages of employing chromatographic fingerprint were investigated and demonstrated for the evaluation of Tianjihuang by systematically comparing chromatograms with a professional analytical software recommended by State Food and Drug Administration (SFDA). Our results revealed that the chromatographic fingerprint combining similarity evaluation could efficiently identify and distinguish raw herbs of Tianjihuang from different sources. The effects resulted from collecting locations, harvesting time and storage time on herbal chromatographic fingerprints were also examined.

Chromatography, High Pressure Liquid↗

PubMed2005

Fiber-optic surface plasmon resonance for vapor phase analyses.

Fiber-optic sensors based on surface plasmon resonance (SPR) for direct refractive index (RI) measurements of samples with the RI between 1.00 and 1.30 are described. Most applications of SPR sensors are designed to function near the refractive index of water (1.3330 RI). The RI changes of aqueous solution (RI, ca. 1.34) can easily be monitored by silica-fiber (RI, 1.4601 at 550 nm) based SPR sensor. With regard to gas species detection, the fiber-optic SPR sensor must be modified for sensitivity to changes in refractive index near 1.0008 (i.e., RI of air). However, the silica waveguide has a prohibitively high RI for unmodified monitoring of the RI changes of gas. The silica-fiber based SPR probe design presented here is based upon the modification of the probe geometry to the ability to tune the SPR coupling wavelength/angle pair. In this study, the tapered silica-based fiber SPR sensors are shown to directly determine the RI changes of gas species and the density change of dry air.

Fiber Optic Technology↗

PubMed2005

Dinuclear macrocyclic polyamine zinc(II) complexes linked with flexible spacers: synthesis, characterization, and DNA cleavage.

Dinuclear macrocyclic polyamine zinc(II) complexes, which have two cyclen groups linked by flexible spacers, have been synthesized as DNA cleavage agents. The structures of these new dinuclear complexes are consistent with the data obtained from elemental analysis, MS and 1H NMR spectroscopy. The catalytic activity of these dinuclear complexes on DNA cleavage was studied. The results showed that the dinuclear zinc(II) complexes can catalyze the cleavage of supercoiled DNA (pUC 19 plasmid DNA) (Form I) under physiological conditions to produce selectively nicked DNA (Form II).

DNA↗

PubMed2005

[Changes in serum contents of inflammatory mediators after tetramethylene-disulfo-tetramine poisoning and clinical study of a new treatment regime for the poisoning].

OBJECTIVE: To study the changes in serum contents of beta-endorphin (beta-EP), endothelins (ET), nitric oxide (NO) and tumor necrosis factor (TNF) after acute tetramethylene-disulfo-tetramine (TDT) poisoning and therapeutic effect of a new treatment regime. METHODS: (1) Forty-eight patients with tetramethylene-disulfo-tetramine poisoning (experiment group) were enrolled in this study. The serum levels of beta-EP, ET, NO and TNF were measured upon hospitalization and 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19 days after poisoning, respectively, and compared with those of 30 healthy individuals (control group B). (2) They were treated with the improved regime and compared with patients treated with the conventional regime designated as control group A. RESULTS: (1) In 48 patients treated with improved regime, 45 were cured and 3 died. (2) The serum levels of beta-EP, ET, NO and TNF from 45 patients who were cured were significantly higher at hospitalization compared with those of healthy individuals, with the peak values appeared on day 1 after poisoning in the mild, moderate and severe groups. Beta-EP levels returned to normal range on days 9, 13 and 17 after poisoning respectively in the mild, moderate and severe groups. ET levels returned to normal range on days 7, 13 and 15 after poisoning respectively in the mild, moderate and severe groups. NO levels returned to normal range on days 7, 11 and 11 after poisoning respectively in the mild, moderate and severe groups. TNF levels returned to normal range on days 9, 11 and 17 after poisoning respectively in the mild, moderate and severe groups. (3) The serum levels of beta-EP, ET, NO and TNF in 3 non-survivors were very high at hospitalization and continued to increase in the course of treatment. (4) The cumulative doses of diazepam and Phenobarbital, and the eclampsia time were significantly less in the experiment group than those of control group A. CONCLUSION: (1) The serum levels of beta-EP, ET, NO and TNF are correlated with the severity of tetramethylene-disulfo-tetramine poisoning and general conditions of the patients. (2) When the serum levels of beta-EP, ET, NO and TNF decrease gradually in the course of treatment, prognosis is better. On the contrary, the prognosis is poor when their levels increase gradually. (3) Measures to decrease levels of beta-EP, ET, NO and TNF result in a better prognosis of patients with tetramethylene-disulfo-tetramine poisoning. (4) The improved regime can be considered a better therapeutic strategy in tetramethylene-disulfo-tetramine poisoning.

Acute Disease↗

PubMed2004

Self-compensating fiber optic flow sensor system and its field applications.

A self-compensating fiber optic flow sensor system based on the principle of broadband white-light interferometers and cantilever beam bending is described. The fiber optic sensor system uses two fiber ferrule sensors that are bonded on either side of a cantilever beam to measure the flow rate by monitoring the air-gap changes caused by the bending of the cantilever beam. Cross sensitivity of the temperature and pressure dependence of the sensor can be compensated for automatically. The prototype sensor system was constructed, laboratory characterized, and field tested. The results from the field testing have demonstrated high resolution, repeatability, and stability for on-line detection of the flow rates of fluids.

Journal Article↗

PubMed2004

[Maternal serum tumor necrosis factor-alpha concentration and correlation with insulin resistance in gestational diabetes].

OBJECTIVE: To investigate serum concentration of tumor necrosis factor (TNF)-alpha and its correlation with insulin resistance in pregnant women with gestational diabetes mellitus (GDM). METHODS: Enzyme-linked immunosorbent assay was used to measure the fasting serum TNF-alpha levels of 42 women with GDM (28 approximately 39 gestational weeks), and 40 cases of normal pregnant women in the third trimester. Fasting plasma glucose, insulin, C-peptide and glycosylated hemoglobin (HbA1c) were also measured at the same time. Insulin sensitive index (ISI) was calculated. RESULTS: (1) Significantly elevated serum TNF-alpha was found in the women with GDM (5.2 +/- 1.6) ng/L as compared with the healthy pregnant women in third trimester (4.5 +/- 0.5) ng/L (P < 0.01); ISI between the two groups was significantly different, (-4.3 +/- 0.5) and (...3.8 +/- 0.3) (P < 0.01). (2) fasting plasma glucose, insulin, C-peptide, HbA1c in GDM group were (5.5 +/- 0.7) mmol/L, (13.4 +/- 3.8) mU/L, (1.6 +/- 0.4) nmol/L, (5.6 +/- 0.5)%, being significantly higher than those in the normal pregnant women (P < 0.01 or P < 0.05). (3) Significant negative linear correlation was revealed between TNF-alpha and ISI (r = -0.703, P < 0.01), and positive linear correlations between TNF-alpha and plasma glucose, C-peptide, and HbA1c were found (r = 0.512, 0.629, 0.386); but no correlation between TNF-alpha and insulin was found in GDM group. In normal group the correlation between ISI and TNF-alpha was also found (r = -0.390, P < 0.05), but less significant than that in the GDM group. CONCLUSIONS: Fasting plasma TNF-alpha levels in pregnant women with GDM is significantly higher than in normal pregnant women. A negative relationship between TNF-alpha and insulin sensitivity index is found in GDM, suggesting increased TNF-alpha may contribute to insulin resistance in pregnant women with gestational diabetes.

Adult↗

PubMed2003

Relationship between nuclear morphometry, DNA content and resectability of pancreatic cancer.

AIM: To investigate the association of nuclear morphometry and DNA content with resectability of pancreatic cancer. METHODS: A total of 36 patients with pancreatic adenocarcinoma were divided into resectable group and unresectable group. The nuclear morphometry and DNA contents of tumor cells were analyzed by IBAS autoimagine analyzer from paraffin-embedded materials. Localization size, histological type and grade, and clinical stage of the tumor were evaluated. Factors influencing resectability of pancreatic cancer were investigated using stepwise regression analysis. RESULTS: Statistical significance was found in nuclear DNA content (integrated optical density, IOD) of tumor cells (1.64+/-0.41 vs 2.96+/-0.55), DNA ploidy, ages (46.5+/-5.3 years vs 58.6+/-0.7 years) and tumor volumes (298.1+/-101.5 cm(3) vs 634.7+/-512.5 cm(3)) in both groups (P<0.05), and no difference was found in the nuclear morphometry (P>0.05). The rates of diploid/tetraploid and aneuploid were 66.7 % and 33.3 % in resectable group respectively, and 38.9 % and 62.1 % in unresectable group, respectively (P<0.05). IOD (X(12)), ploidy status (X(12)) and clinical stage (X(3)) were radical resectable indicators with statistical significance. The regression equation for resectability was Y=-9.2053+3.5428X(12)+2.5390X(13)-2.3001X(3) (RR=0.8780, P<0.01). CONCLUSION: There is a high correlation between resectability of pancreatic cancers and their DNA contents, DNA ploidy status and clinical stage.

Adenocarcinoma↗

PubMed2003

[Optimizing cultural conditions of measles vaccine working seed lot with orthogonal experiments].

OBJECTIVE: To improve the quality of measles vaccine and find out good combination of cultural factors of measles vaccine virus seeds. METHODS: Orthogonal experiments were made to confirm optimized cultural factors. 5 lots of optimized measles vaccine working seed lot were prepared. RESULTS: The titers of the optimized vaccine seed improved significantly (> or = 0.69 +/- 0.35 LgCCID50/1.0 ml, P < 0.05), compared with 5 lots of traditional working seed lot. With these seeds we trial-prepared 5 lots of lyophilized vaccines respectively, the titer and stability met the Chinese Requirements of Biological Products. CONCLUSION: The orthogonal experiment is a kind of good method for optimizing cultural conditions of measles vaccine working seed lot. The yield and quality of measles vaccine can be improved in the optimized working seed lot with high titer and good stability.

Culture Media↗

PubMed2003

[The status quo of perimenopausal and postmenopausal women in Chengdu: report of a population-based cross-sectional study].

OBJECTIVE: To investigate the situation of reproductive health of perimenopausal and postmenopausal women in Chengdu and provide a basis for planning reproductive health care for these women. METHODS: We conducted a population-based cross-sectional study in women who were over 45 years old in the central city and the nearby county of Chengdu. RESULTS: The mean age of menopause was 48.1 years. There were sixty percent of women who had dysfunctional uterine bleeding before menopause. About half of the postmenopausal women had experienced perimenopausal symptoms. There were 460 women who ever used or currently use estrogen therapy. But only half of them visited doctors and sought medical therapy. And the main problems were hot flash, night sweats, dyssomnia, and urinary infection. Most of them took medicine for a short period (< 1 year). CONCLUSION: We found that middle-aged and older women have many symptoms related to menopause. It is necessary for us to provide reproductive health care for them.

Aged↗