Biomedical subjects

H Li

Publications and source records attributed to H Li.

At least 685 records · Page 38Linked to original sources

PubMed2000

Primary biliary cirrhosis and autoimmunity: evaluating the genetic risk.

The genetic basis of autoimmunity is receiving increased attention. Organ-specific diseases, such as primary biliary cirrhosis, may be considered model diseases to use for development of databases and extrapolation to other autoimmune diseases. PBC is an enigmatic autoimmune disease that predominantly affects females and leads to destruction of intrahepatic bile ducts. The serologic hallmark of this disease is anti-mitochondrial antibodies that specifically react with the E2 components of 2-oxodehydrogenase enzymes, including PDC-E2. There are no clear major histocompatibility complex associations with the development of PBC, despite the observation that first-degree relatives of index patients with PBC have a 4-6% prevalence of development of PBC. This risk factor is comparable or higher than any other human autoimmune disease and suggests that a genome-wide approach towards dissection of genetic associations would lead to valuable new insights. In this review we place these concepts in perspective and highlight in particular the genetic associations in primary biliary cirrhosis.

Adult↗

PubMed2000

[Effect of different source iron on piglet's growth, metabolism and environment].

In order to approach the effect of different source Fe on piglet's growth, metabolism and environment, an experiment was conducted with 158 suckling pigs from 15 litters, which were randomly allocated to group I, II and III, and fed with diet I (basal diet + FeSO4.H2O), II (basal diet + Fe-citric acid) and III (basal diet + Fe-methionine complex), respectively. Each of the diets contained 146 mg.kg-1 Fe. The results show that after the experiment ended, the body weight, daily increment, grades for appearance and behavior, hemoglobin concentration in blood, Fe-transferring albumen concentration in plasma, and Fe contents in plasma and liver of 35 days old piglets in group II and III were higher (P < 0.05 or P < 0.01) than those in group I, while the feed conversion, diarrhea incidence, fecal amount and its Fe content of the piglets in group II and III were lower (P < 0.05 or P < 0.01) than those in group I. The body weight and daily gain of the piglets in group III were also higher (P < 0.05) than those in group II, but no significant differences (P > 0.05) in other traits between group II and III. It is suggested that Fe-methionine complex and Fe-citric acid could improve piglet's health, growth and development, feed conversion, and physiological and biochemical parameters, increase the absorption and utilization of Fe by piglet's body, and decrease the fecal amount and its Fe content. Both of them should be effective and safe Fe sources for suckling pigs.

Animals↗

PubMed2000

[Dynamics of respiration pathway in transgenic salt-tolerant wheat and its receptor under salt stress].

Using transgenic salt-tolerant wheat 89122 and its receptor Longchun 13 as test material, the dynamic changes of respiration pathway of wheat seedlings at different salt concentration were studied. The appearance of salt respiration was later in 89122 than in Longchun 13. The changes of Valt and rho Valt of both varieties had different patterns during salt stress process. Valt was suppressed by high salt levels, but could be induced by low salt levels in Longchun 13. The rho Valt and rho' Vcyt of two varieties were cooperatively regulated with each other to adapt to salt stress, and rho' Vcyt was the main electron transport pathway. The possible physiological roles of cyanide-resistant respiration were also discussed. It was suggested that the operation intensity of cyanide-resistant respiration could serve as a physiological index of plant salt-tolerance.

Oxygen Consumption↗

PubMed2000

[Dynamic changes of respiration pathway and active oxygen levels in subcultured tobacco callus].

During the growth and senescence of tobacco callus, the total respiration rate showed two peaks on the 11th and 19th day, respectively. The development and operation of alternative pathway increased gradually, reached the maximum between two respiration peaks, and then declined in the following days, but the cytochrome pathway was still as a main electron transport pathway consistently. Analysis on the levels of active oxygen species during the growth and senescence process in tobacco callus suggested that H2O2 and O2.- were involved in some way in the induction of the development and operation of the alternative pathway, but the increase of production rate of OH might suppress both the development and operation of the alternative pathway, which were enhanced by H2O2 and O2.- respectively. These results were further proved by the use of active oxygen scavengers. The possible participation of the alternative pathway enhanced by active oxygen in the initial senescence process was discussed.

Cells, Cultured↗

PubMed2000

[Age structure of tillers of Hordeum brevisulatum clone in Songnen plain of China].

The tillers of Hordeum brevisulatum clone have a significantly expanding age structure, which includes three age classes. The 1st age class tillers are absolutely dominant in the reproductive growth of the clone. The older the tillers, the smaller the rate of quantitative increase, and the less the accumulative nutrients are. The quantity and biomass of the 1st and 2nd age classes increase with the size and the tiller number of the clone, while the 3rd age class tillers are positively linearly interrelated to the total tillers of the clone. The mean weight per tiller decreases with the age class increased. The mean weight per reproductive tiller is relatively constant among three age classes, and that of the 1st tillers of clone has a negative respondence to the density of tiller. The age structure of the potential population of clone is also of an obviously expanding type. The buds on the vegetative tillers are always more than those on the reproductive tillers. The buds on the vegetative or reproductive tillers of every age class are all positively interrelated to the size and the total tillers of clone.

Biomass↗

PubMed2000

[Phosphate adsorption characteristics of paddy soils derived from main parent materials in Guangdong Province].

Isothermal adsorption experiment of phosphate on paddy soils drived from five different parent materials in Guangdong Province was carried out. The result showed that the adsorption data of different test soils could be simulated well by Langmuir, Freundlich and Temkin equations, and the Langmuir equation fitted the data best (correlation coefficient r: 0.995-0.999..). As a value of phosphate adsorption characteristics, the product of phosphate adsorption maximum (Xm)and sorption intensity factor(K) calculated by Langmuir equation could be a comprehensive index to characterize the potential phosphate adsorption by paddy soil, and could indicate the order of applying phosphate. The result also indicated that there exists two types of sorption region on the soils tested.

Absorption↗

PubMed2000

Different Wnt-5A gene expressions in the renal cell carcinoma GRC-1 cell line during the cell cycle.

OBJECTIVE: To investigate the gene expression at transcription level of growth factor Wnt-5A in different phase during the cell cycle. METHODS: We synchronized the renal cell carcinoma GRC-1 cell line by double thymidine blocks and high-pressure N2O gae methods and amplified Wnt-5A cDNAs from different phase using Semi-quantitative RT-PCR (reverse transcriptase polymerase chain reaction). The PCR products were electrophoresized on the agrose gel and detected by Gel Doc 1000 computer controlled system integrating the volumes of each band, representing the intensities of all pixels in a defined band. RESULTS: The different mRNA expressions of growth factor Wnt-5A was detected in RCC GRC-1 cell line. In S phase, the highest level of Wnt-5A transcript was observed, and in G1 and M phase, medial and lowest, respectively. The differences between S and M stages were statistically significant (P < 0.05). CONCLUSION: Growth factor Wnt-5A has the potential effect on tumorigenesis. It contributes to all phases during cell cycle but in S phase especially.

Carcinoma, Renal Cell↗

PubMed2000

The major achievements of biological products in China.

PURPOSE: To review the major achievements of biological products of China in the scientific research and development. DATA SOURCES: The contents of this article were selected from the original essays or reviews related to biologicals published in Chinese and foreign journals. STUDY SELECTIONS: Briefly original articles and reviews of text books published by Chinese authors in the last twenty years were selected. DATA EXTRACTION: These data have addressed the novel vaccines and engineering genetic technologies on biologicals. RESULTS: Nowadays about 200 kinds of biological products are produced in China ranging from preventive vaccines as the majority to therapeutic and diagnostic products. About 800-900 million doses of vaccines for the purpose of prophylaxis are administered annually. Biologicals have played an important role in the prevention of infectious diseases. During the former 30 years the basis for the further development of research work was set up and in the latter 20 years new achievements were made one after another, for example, the development of attenuated JE vaccine, hepatitis A live vaccine, HFRS inactivated vaccine, recombinant HB vaccine and Vi typhoid vaccine, et al. CONCLUSION: During the past 50 years, China has made a great progress in the field of biological products, however we are still week in the aspect of basis research and backward behind the developed countries in originating new products.

Biological Products↗

PubMed2000

[Field epidemiological and experimental study on relationship between genetic factor and nonresponse or hyporesponse to hepatitis B vaccine].

OBJECTIVE: To evaluate the role of genetic factor in the development of nonresponder or hyporesponder to hepatitis B vaccine in Chinese people from field epidemiology and experimental study. METHODS: Six hundred and thirty-four susceptible healthy students were vaccinated with three doses of plasma-derived hepatitis B vaccine. Twenty-nine non- or hypo-responders (subjects) and 30 hyperresponders (controls) as well as their 80 and 79 first degree relatives were determined and recruited in the study. The first degree relatives of subjects and controls were then immunized with hepatitis B vaccine and followed up. On the basis of the above results, alleles of HLA-A, B, C, DR and DQ locus were further detected in the two groups. RESULTS: The non- and hypo-response rate in immunized students was 4.6% (29/634). After administered with hepatitis B vaccine, the first degree relatives of the subjects displayed a 17.9% frequency of nonresponsiveness, higher than in the controls. The phenotype frequency of HLA-DR7 and B54 was 52.2% and 21.7% in subjects, 9.1% and 0.0% higher than in controls, respectively. The extended haplotype B54-DR7 was more frequent in the former (17.0%) than in the latter (0.0%) (P < 0.01). CONCLUSION: These results demonstrated that the genetic factor was likely associated with the non- and hypo-response to hepatitis B vaccine in Chinese people.

Adolescent↗

PubMed2000

Suppression of induced atherosclerosis in h-apo AI transgenic mice by overexpression of human apo AI in the aortic wall.

OBJECTIVES: To investigate the inhibitory effect of expressed human apolipoprotein AI (h-apo AI) and high density lipoprotein (HDL) on atherosclerosis development in transgenic mice, and cultivation of smooth muscle cells isolated from the aortic wall of transgenic mice that are able to produce human apo AI in vitro. METHODS: Both h-apo AI transgenic mice and normal C57 mice were fed with either a regular chow or a high-fat diet containing 5% pork lard, 1.25% cholesterol and 0.25% sodium cholate for 14 or 24 weeks respectively. Human apo AI mRNA were detected by Northern blot. Plasma apo AI levels were measured using a radio-immuno-diffusion assay, and plasma lipid levels were measured using a colorimetric assay. Image analysis was performed in order to quantify the fatty streak areas stained with oil red O. In addition, smooth muscle cells isolated from the media layer of the aortic wall of h-apo AI transgenic mice were cultured for the detection of human apo AI produced. RESULTS: Higher levels of h-apo AI mRNA were found in liver, small intestine, kidneys and aortae in transgenic mice than in the controls all on a high-fat diet. The transgenic mice had an increased level of serum apo AI and HDL-cholesterol and the fatty streak area counted at the aortic sinus was approximately 5-fold less in the transgenic mice after feeding with a high fat ration, particularly after 24 weeks. SMC isolated from the transgenic mice aortae were cultivated and able to express h-apo AI mRNA and its related protein. CONCLUSION: Elevation of h-apo AI and HDL in serum and aortic wall of the transgenic mice has a remarkably inhibitory effect on the development of experimental atherosclerosis.

Animals↗

PubMed2000

Carcinoma of the lung and multiple primary tumors.

OBJECTIVE: To assess the incidence of multiple primary malignancies combined with lung and other organs. METHODS: All patients who were consecutively treated for lung cancer from December 1964 to December 1992 were retrospectively analyzed regarding the occurrence of simultaneous primary tumor elsewhere in the body. RESULTS: Of 1019 patients reviewed, 21 (2.1%) had associated carcinoma of other organs. In these 21 patients, the incidence of associated aerodigestive tract cancer was 71% and cancer of other organs was 29%. Five patients had simultaneous cancer with the lung cancer and 16 metachronous lung cancer associated with cancer of other organs. CONCLUSIONS: Multiple primary tumors in patients with carcinoma of the lung is not a rare phenomenon. Surveillance programs for detection of second primary tumors should focus on this group of patients. Surgeons should be aware of the possibility of double cancer, and the patient's condition and stage of the carcinoma must be taken into consideration in the determination of operative indications and method.

Adrenal Gland Neoplasms↗

PubMed2000

Deletion of chromosomes 9p and 17 associated with abnormal expression of p53, p16/MTS1 and p15/MTS2 gene protein in hepatocellular carcinomas.

OBJECTIVE: Fifteen loci on chromosome 9p and 17 were analyzed to clarify the involvement of loss of heterozygosity (LOH) in hepatocellular carcinoma (HCC) in Chinese patients positive for hepatitis B (HBV) and/or hepatitis C (HCV) infection. Expression of tumor suppressor genes (TSG) of p53, p16, and p15 gene was found to correlate with a deletion of these genes. METHODS: Immunohistochemistry and PCR-based microsatellite polymorphism analysis techniques were used. RESULTS: A high frequency of LOH was detected on chromosome 9p24 at locus D9S54 (61.8%) and 9p21, concentrated at loci D9S1747 (52.4%) and D9S1752 (51.8%). On chromosome 17, high frequent LOH was concentrated on 17p at the p53 gene locus (53.8%) and locus D17S520 (52.8%). p53 protein expression was increased in HCC, which correlated with p53 gene loss. Expression of p16 and p15 protein decreased in HCC when LOH occurred at locus D9S1752 (p15 gene locus) or at locus D9S1747 and D9S1748 (p16 gene is located between these 2 loci). LOH at the p53 gene and p15 gene loci was closely associated with HBV and HCV co-infection in HCC. No significant relationship between LOH and HCC clinico-pathological outcomes was observed. CONCLUSION: High frequency LOH occurs on chromosomes 9p and 17 in HCC in Chinese patients. Such sites may contain several putative tumor suppressor genes critically involved in the development and/or progression of HCC. Deletion of p53, p16, or p15 tumor suppressor genes may cause abnormal expression of the protein product of these genes. HBV and/or HCV infection may be closely associated with LOH p53 and/or p15 gene expression.

Adult↗

PubMed2000

HLA alleles in patients with Guillain-Barre syndrome.

OBJECTIVE: To determine whether genetic factors may work in concert with autoimmune factors in the pathogenesis of Guillain-Barre syndrome (GBS). METHODS: We determined the differences in the distribution of HLA alleles between GBS patients and normal controls. HLA-DQA, -DQB and -DRB alleles were typed by the sequence specific primer polymerase chain reaction (PCR-SSP) methods in 47 GBS, 7 patients with Campylobacter jejuni (CJ) enteritis and 50 normal controls. RESULTS: There were no differences in the frequency of HLA-DQA, -DQB and -DRB among GBS group, CJ group, normal controls and GBS subgroups with respect to recent CJ infection, GM1 IgG and GM1 IgM antibodies (P > 0.05). There was an increasing tendency of DQA1 * 0301 (P = 0.056, RR = 2.991) in the subgroup with GM1 IgG antibodies and DQA1 * 0302 (P = 0.087, RR = 3.587) in the subgroup with recent CJ infection. No difference was found among GBS, CJ enteritis patients and normal controls. CONCLUSIONS: The increasing tendency of the two alleles suggests that there may be some relation between genetic factors and immunological factors, but a definite conclusion waits for more cases.

Alleles↗

PubMed2000

Selective loss of basal forebrain cholinergic neurons in APP770 transgenic mice.

OBJECTIVE: To determine whether cholinergic neurons in the basal nucleus magnocellularis (NBM) and the medial septum are affected in transgenic mice overexpressing human amyloid precursor protein 770 (APP770). METHODS: Eight age groups, from 3 months old to 10 months old, of either heterozygous transgenic or non-transgenic mice were used for choline acetyltransferase (ChAT) staining using immunohistochemistry. The number of ChAT-positive neurons was counted on the MCID Image Analysis System. Neurons in the cerebral cortex and area CA1 of hippocampus were also stained with cresyl violet and counted using optical dissector technique. RESULTS: There is no change in the number of forebrain cholinergic neurons in the transgenic mice up to 9 months of age. A loss of these cholinergic neurons starts in 9 months old transgenic mice, with a further decrease in the number of NBM and medial septum neurons in 10-month-old transgenic mice. On the other hand, the number of neurons in the cerebral cortex and hippocampal area CA1 remained unchanged. CONCLUSION: These results demonstrate a selective loss of basal forebrain cholinergic neurons in APP770 transgenic mice.

Amyloid beta-Protein Precursor↗

PubMed2000

[Determination of tumor necrosis factor-alpha and interleukin-6 levels of the tubal fluids in patients with infertility caused by infection of Chlamydia trachomatis].

OBJECTIVE: To study the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in tubal fluids of tubal factor infertile (TFI) women due to chlamydia trachomatis (CT) infection and its implication. METHODS: Twenty-two TFI women with CT infection (group A), twenty-three TFI women without CT infection (group B) and nineteen fertile women with normal tubes (group control) were enrolled for study. Levels of TNF-alpha and IL-6 in tubal fluids were measured by enzyme-linked immunosorbent assay. RESULTS: Group A had significantly higher TNF-alpha levels than those of group control (178 ng/L versus 124 ng/L, P < 0.01). Moreover, women with tubal blocks had significantly higher TNF-alpha those of tubal adhesions (199 ng/L versus 142 ng/L, P < 0.01). IL-6 levels of group A were significantly higher than those of group B and group control (681 ng/L versus 264 ng/L and 229 ng/L, both P < 0.01), but there is no difference between group B and group control. CONCLUSIONS: Local TNF-alpha and IL-6 levels increased in silent tubal infection of CT. TNF-alpha had a positive relevance with the degree of tubal damage.

Adult↗

PubMed2000

[Combined hepatic artery chemoembolization and portal vein chemotherapy after radical resection of hepatocellular carcinoma to prevent recurrence].

OBJECTIVE: To study the value of combined hepatic artery chemoembolization (HACE) and portal vein chemotherapy (PVC) after radical resection of hepatocellular carcinoma (HCC) to prevent recurrence. METHODS: From August 1991 to July 1995, 81 HCC patients were undergone radical tumor resection. After operation, combined treatment with HACE and PVC was given in group I (28 cases), HACE alone in group II (30 cases), nothing in group III (28 cases). All patients were followed up over 3 years. RESULTS: Recurrence rate at one year after surgery was significantly lower in group I and II than in group III; at two years, it was lower in group I than in group II and III. Survival rate at one year was notably higher in group I and II than in group III; at 2 years, it was higher in group I than in group II and III. Recurrence rate and survival rate were similar in group I and group II at 3 and 5 years after surgery. Tumor larger than 5 cm, no capsule, multiple foci, AFP > 400 micrograms/L were high risk factors of postoperative recurrence. CONCLUSION: After radical resection of HCC, combined use of HACE and PVC is superior to HACE alone to reduce recurrence rate and to increase survival rate within 2 years after operation. Such remarkable difference no more exists at 3 and 5 years following operation.

Adult↗

PubMed2000

[Infusion chemotherapy and chemoembolization of liver metastases from cancer of the alimentary tract].

OBJECTIVE: To evaluate the efficacy of hepatic artery infusion chemotherapy and chemoembolization in the treatment of liver metastases from alimentary tract cancer. METHODS: A total of 92 patients with unresectable liver metastases from alimentary tract cancer was treated 316 times by hepatic artery infusion chemotherapy and chemoembolization. Of the 92 patients, only infusion chemotherapy was performed in 29 patients, and infusion chemotherapy and chemoembolization in 63 patients. Chemotherapy was carried out with a combination of epirubicin and/or cisplatin, mitomycin-C, calcium folinate and 5-fluorouracil. Embolization was accomplished with lipiodol ultra-fluid or lipiodol ultra-fluid and gelatin sponge. Response rates were assessed by CT scanning. RESULTS: An overall response rate (CR + PR) of the cases was 45.7%. The mean survival period of 92 patients was 19.6 months. The 0.5-, 1-, 2-, 3- and 5-year survival rate was 95.7%, 73.8%, 30.9%, 17.6% and 9.9%, respectively. Best therapeutic results were obtained in 9 cases with single metastatic focus in the liver, with a mean survival period of 31.2 months. There was no severe side effect or complication. CONCLUSION: Treatment by transcatheter hepatic artery infusion chemotherapy and chemoembolization is beneficial to patients with metastatic cancer of the liver.

Adult↗

PubMed2000

[Imaging findings of intrahepatic peripheral cholangiocarcinoma].

OBJECTIVE: To study the imaging features of intrahepatic peripheral cholangiocarcinoma. METHODS: The imaging features of 11 cases of surgically and pathologically confirmed intrahepatic peripheral cholangiocarcinoma were retrospectively reviewed. B-ultrasonic scanning(BUS) was performed in all patients. CT was done in 8 patients, including conventional unenhanced scanning followed by enhanced scanning in 4 patients, dynamic double-stage scanning in 2 patients, and dynamic double-stage scanning followed by delayed scanning in the other 2 patients. Of the 3 patients received MRI, conventional SE series, T1WI and T2WI were performed in 2 patients, conventional SE series and dynamic scanning in the other one. RESULTS: All lesions were hypo-echoic in BUS, homogeneous or heterogeneous. On unenhanced CT, the lesions were of low density with ill-defined border. On enhanced scanning, moderate enhancement was observed at the edge of the lesions. MRI was of low intensity in T1WI and moderately high intensity in T2WI. Dynamic MRI and double-stage CT scanning showed characteristic enhancement from the periphery toward the center of the lesion. Focal dilatation of the intrahepatic bile ducts around the tumor was seen in 6 cases and retraction of liver capsule in 3 cases. CONCLUSION: To some extent, the imaging features of intrahepatic peripheral cholangiocarcinoma are characteristic. They are useful for differentiating these tumors from other space-occupying lesions in the liver.

Aged↗