Biomedical subjects
Publications and source records attributed to S Peng.
A novel method for the identification of ventricular wave based on wavelet transform is presented. First, "Multi-Scale Intersectional Search" is adopted for analysis of wavelet transform coefficients on some different scales, then adaptive detection is used on this basis. The results of practice show that it has a discrimination of 94.5%, and is obviously superior to any routime method.
ICP-AES was used for the direct determination of 15 rare earth elements in synthetic solutions and real sample. Spectral interferences between REEs in the mixtures of rare earth were investigated with a high-resolution echelle spectrometer and suitable analytical lines of 15 rare earth elements were selected. The Multicomponent Spectral Fitting(MSF) models were made. The method was used to remove spectral interferences and background. The factors influence the modes were discussed. The influences of acidity and ICP parameters were investigated. The compromise condition of simultaneous determination of 15 REEs was selected. Axially viewed ICP torch was used to determine 15 REEs, The detection limits are Y 0.21 microgram.L-1, La 9.1 micrograms.L-1, Ce 14.1 micrograms.L-1, Pr 1.9 micrograms.L-1, Nd 7.8 micrograms.L-1, Tm 0.37 microgram.L-1, Yb 0.12, Lu microgram.L-1, Ho 0.06 microgram.L-1, Er 0.06 microgram.L-1, Tb 0.53 microgram.L-1, Sm 1.14 micrograms.L-1, Eu 0.09 microgram.L-1, Dy 0.08 microgram.L-1, Gd 0.30 microgram.L-1. The recoveries of this procedure are between 98.4% and 101.7%. The RSD is within 2%. The method is rapid and accuracy.
A study was carried out on the contents of nutritional elements in some medicine-food flowers by atomic absorption spectrometry. The results showed that flowers contain much more contents Fe, Ca, Mg and Co. The range of the average recovery in this method is 94%-108%, which indicate that the method we used is practicable. And flower is a kind of typical food source of containing high content of K and low content of Na. It is worth much more comprehensive utilization.
The human endogenous retrovirus K (HERV-K) family of endogenous retroviruses consists of approximately 50 proviral copies per haploid human genome. Herein, the HERV-Ks are shown to encode a sequence-specific nuclear RNA export factor, termed K-Rev, that is functionally analogous to the HIV-1 Rev protein. Like HIV-1 Rev, K-Rev binds to both the Crm1 nuclear export factor and to a cis-acting viral RNA target to activate nuclear export of unspliced RNAs. Surprisingly, this HERV-K RNA sequence, which is encoded within the HERV-K long terminal repeat, is also recognized by HIV-1 Rev. These data provide surprising evidence for an evolutionary link between HIV-1 and a group of endogenous retroviruses that first entered the human genome approximately 30 million years ago.
BACKGROUND: Recent case studies in Korea and animal studies revealed the reproductive and hematopoietic toxicity of 2-bromopropane introduced into workplaces as an alternative to ozone-layer depleting chlorofluorocarbons. We aimed to clarify the dose-effect relationship of 2-bromopropane in workers. METHOD: The exposure concentration of 2-bromopropane and hematological indices, hormonal levels, menstruation status, and sperm indices were examined in 25 workers (11 males, 14 females) at a 2-bromopropane factory. Regression analyses of the examined indices against time-weighted average (TWA) of exposure concentration were conducted. RESULTS: Amenorrhea or polymenorrhea was observed only in older females. Hematological indices had a significant relation with TWA of exposure concentration in females with normal menstruation. However, no other indices showed any significant relation with TWA of 2-bromopropane. CONCLUSIONS: No severe cases of reproductive or hematopoietic disorders were found at less than 10 ppm (TWA), but a possible adverse effect of 2-bromopropane on hematopoiesis could not be disproved.
The conventional paradigm to explain systemic lupus erythematosus (SLE) is that disease results from tissue deposition of pathogenic autoantibodies and immune complexes, secondary to activation of autoreactive B cells in the context of help from alphabeta T cells. Recent work in murine lupus has confirmed this notion and demonstrated that autoantigen-specific alphabeta T cells are absolutely required for full penetrance of disease, with such autoreactive alphabeta T cells, even in Fas-intact mice, likely arising from defects in peripheral tolerance. These studies have also revealed a network of regulation that also involves nonclassical pathogenic and downregulatory alphabeta and gammadelta T cells, suggesting that the lupus immune system involves more complex interactions than the conventional paradigm suggests.
The green fluorescent protein (GFP) from the jellyfish Aequorea victoria has attracted widespread interest since it was demonstrated to be fluorescent in vivo when expressed in other organisms. In order to investigate papillomavirus life cycle which hampered by the unavailability of conventional cell culture system, we constructed a chimeric bovine papillomavirus (BPV) type 1 virus-like particles (VLPs) containing GFP. It was found that fluorescent VLPs could be assembled from L2 protein in which GFP is inserted into the N-terminal region of L2 (aa 88). The fluorescent VLPs could also be assembled from a GFP/L2 fusion protein in which part of the L2 sequence had been deleted. In vitro, fluorescent VLPs could bind to CV-1 cells, and this VLP/cell interaction could be analyzed by FACS assay. These results demonstrated that GFP could incorporate into BPV1 VLPs without disruption of the VLP structure. Fluorescent VLPs might be a useful tool for study of papillomavirus virus/cell interaction.
A series of novel dithiocarbamates, disodium salts of N-glucamyl-N-dithiocarboxyl-amino acids, were synthesized, and their usefullness as an antagonist of cadmium intoxication was investigated. These chelating agents were found to be effective in both acute and repeated exposure cadmium poisoning. The results showed that the cadmium mobilizing properties of disodium N-(2,3,4,5, 6-pentahydroxylhexyl)-N-dithiocarbamate-L-threoninate and disodium N-(2,3,4,5,6-pentahydroxylhexyl)-N-dithiocarbamate-L-cysteinate are clearly superior to those of sodium N-(4-methoxybenzyl)-D-glucamine-N-carbodithioate (MeOBGDTC) revealed in the experiments described here. The toxicity of these novel compounds is modest, and their effect on the concentrations of essential metal ions in the renal cortex is quite small in comparison with that of a group treated with cadmium only. The new dithiocarbomates were identified by MS, rather than by elemental analysis, as they were extremely hygroscopic.
To investigate human papillomavirus (HPV) virus-like particle (VLP)-specific antibody responses among anogenital warts patients, a VLP-based capture ELISA was established. Twenty-six percent (35/134) of control subjects and 50.0% (39/78) of patients with current anogenital warts showed IgG seropositivity to HPV 6b VLPs. HPV 6b VLP-specific antibody responses recognised native VLPs only, and had no cross-reaction with HPV type 16 VLPs. No differences in reactivity were observed between L1 and L1 + L2 VLPs, suggesting that L2 contributes little to the total immunogenicity of the papillomavirus virion. A VLP-cell binding assay was also established. Some sera from patients with anogenital warts specifically inhibited VLP binding to the surface of epithelial cells, suggesting that these antibodies might be functionally neutralising. These data show that serological responses to HPV 6b VLPs were induced among some but not all patients with anogenital warts, and give a proportional estimate of infection in the community.
Photosynthesis and photoinhibition in field-grown rice (Oryza sativa L.) were examined in relation to leaf age and orientation. Two varieties (IR72 and IR65598-112-2 [BSI206]) were grown in the field in the Philippines during the dry season under highly irrigated, well-fertilized conditions. Flag leaves were examined 60 and 100 d after transplanting. Because of the upright nature of 60-d-old rice leaves, patterns of photosynthesis were determined by solar movements: light falling on the exposed surface in the morning, a low incident angle of irradiance at midday, and light striking the opposite side of the leaf blade in the afternoon. There was an early morning burst of CO2 assimilation and high levels of saturation of photosystem II electron transfer as incident irradiance reached a maximum level. However, by midday the photochemical efficiency increased again almost to maximum. Leaves that were 100 d old possessed a more horizontal orientation and were found to suffer greater levels of photoinhibition than younger leaves, and this was accompanied by increases in the de-epoxidation state of the xanthophyll cycle. Older leaves had significantly lower chlorophyll content but only slightly diminished photosynthesis capacity.
OBJECTIVE: To evaluate the relationship between P-glycoprotein expression and anti-cancer drug resistance of gallbladder carcinoma and the use of P-glycoprotein as a biomarker of gallbladder carcinoma, the expression of P-glycoprotein was detected in benign and malignant gallbladder neoplasms and normal gallbladder tissues. METHODS: Alkaline phosphatase anti-alkaline phosphatase (APAAP) method was used to detect the expression of P-glycoprotein in different gallbladder tissues (gallbladder carcinoma, 26 cases; benign gallbladder neoplasm, 14 cases; and normal gallbladder tissue, 9 cases). The relationship between expression of P-glycoprotein, TNM stages and other clinical data of gallbladder carcinoma was also analyzed. RESULTS: Immunohistochemical staining with a monoclonal antibody JSB-1, P-glycoprotein was positive in 76.9% (20/26) of gallbladder carcinomas, in 35.7% (5/14) of benign gallbladder neoplasms and in 33.3% (3/9) of normal gallbladder tissues (P < 0.05). With another monoclonal antibody UIC-2, the positive rates were 69.2% (18/26), 21.4% (3/14) and 11.1% (1/9), respectively (P < 0.01). There was no significant correlation between P-glycoprotein expression and gallbladder carcinoma TNM staging. CONCLUSION: The results suggest that P-glycoprotein probably plays an important role in the poor response of gallbladdar carcinoma to chemotherapeutic agents. In addition, P-glycoprotein may be used a valuable biomarker of gallbladder carcinoma.
OBJECTIVE: To assess the role of CT in the diagnosis, staging and post-treatment follow-up of esthesioneuroblastoma. METHODS: Thirteen cases of pathologically comfirmed esthesioneuroblastoma were analysed retrospectively. RESULTS: On preoperative check up, according to Kadish staging, no case was in stage A, 4 cases were in stage B, 7 in stage C. Tumor scans showed soft tissue density. In 3 cases, calcification was found inside of the tumor. In the 4 cases on scan and enhanced CT, the tumors were heterogeneously enhanced in 3. On enhanced CT, the tumor density was obviously higher than that of the surrounding soft tissue in 6 cases. Postoperative follow-up CT revealed tumor recurrence within 3 months to 2 years in 4 cases. Tumor invasion involved nasal cavity and ethmoid sinus(13 cases), maxillary sinus (12 cases), sphenoid sinus(10 cases), frontal sinus (2 cases), orbit (7 cases). Intracranial invasion occurred in 3 cases, and lymph node metastases in 4 cases. CONCLUSION: CT is valuable in pre-operative staging and monitoring recurrence of esthesioneuroblastoma. Although esthesioneuroblastoma has characteristic CT features on enhancement and multiple invasions to neighboring structures, reliable diagnosis is dependent on pathological confirmation.
OBJECTIVE: To summarize the experience in caudate lobectomy for 26 cases. METHODS: Caudate lobectomy was performed in 26 cases by Peng's multifunctional operative dissector (PMOD) to transect the liver parenchyma (Curettage and Aspiration technique). Primary liver cancer was noted in 18 cases, hilar cholangiocarcinoma in 4, gallbladder carcinoma in 1, right adrenocortical adenocarcinoma in 1, hepatoangioma in 1 and hepatoangiosarcoma in 1. Five cases underwent isolated caudate lobectomy, 1 combined caudate lobectomy with right trisegmentectomy, 6 combined caudate lobectomy with right hemihepatectomy, 9 combined caudate lobectomy with left hemihepatectomy, and 5 combined caudate lobectomy with segmentectomy. RESULTS: The operations were carried out successfully. Follow up for 2 - 23 months, 1 case died from pulmonary infraction 2 weeks after operation, 1 died from lung metastasis 2 months after operation, 10 died from tumor recurrence or metastasis 3, 11, 12, 15, 15, 15, 15, 19, 30, 30 months after operation respectively. The other 14 cases are still alive for 2 to 18 months. CONCLUSIONS: With PMOD, it is possible to dissect the structure precisely. Therefore the caudate lobe can be isolated from the three porta hepatis without much difficulty. Caudectomy can be performed safely.
Explore the source record for details and available documents.
Six highly excited 1pig states of the Na2 molecule have been investigated by optical-optical double resonance (OODR) flourescence excitation spectroscopy. Absolute vibrational numberings are determined and molecular constants and RKR potential curves are obtained. The lowest 10 1pig states have been relabeled according to the hydrogenic nllambda characters of the Rydberg orbital and classified into core-penetrating and core-nonpenetrating Rydberg states.
Ion detection technique has been successfully used in the study of Rydberg states of Na2 by pulse optical-optical double resonance. High-lying Rydberg states near ionization limit have been observed and high sensitive and high gain spectra have been obtained. This technique is very useful for molecular spectroscopy.
The relationship between resolution limit and step-motor parameter in monochromator has been discussed by optical method, which offers an experimental method for optimum utilization of the resolution limit and some reference example for improving resolution by using a step-motor.
The quantities of 21 microelements were determined in 10 Chinese traditional medicines, using both flame and graphite oven atomic absorption spectrometry. We studied the efficacies of such Chinese medicaments. The result showed the efficacies related to the inorganic microelements.