Biomedical subjects

J D Liu

Publications and source records attributed to J D Liu.

At least 19 recordsLinked to original sources

PubMed2003

Molecular cytogenetic detection of paternal chromosome fragments in allogynogenetic gibel carp, Carassius auratus gibelio Bloch.

In gynogenesis, sperm from related species activates egg and embryonic development, but normally does not contribute genetically to the offspring. In gibel carp, Carassius auratus gibelio Bloch, however, gynogenetic offspring often show some phenotypes apparently derived from the heterologous sperm donor. This paternal effect of allogynogenesis is outstanding in an artificial clone F produced by cold treatment of clone E eggs after insemination with blunt-nose black bream (Megaloabrama amblycephala Yin) sperm. Karyotype analysis revealed 5-15 supernumerary microchromosomes in different individuals of clone F in addition to 156 normal chromosomes inherited from the maternal clone E. A painting probe was prepared from the microdissected microchromosomes, and used to investigate the origin of these microchromosomes. Strong positive signals were detected on each microchromosomes of clone F and on 4 pairs of chromosomes in blunt-nose black bream, whereas no signals were detected on the chromosomes of clone E. This result indicates that some paternal chromosome fragments of blunt-nose black bream have been incorporated into the artificial clone F. Therefore, the manipulation of allogynogenesis may provide a unique method to transfer DNA between diverse species for fish breeding.

Animals↗

PubMed2002

Sex chromosomes in the spiny eel (Mastacembelus aculeatus) revealed by mitotic and meiotic analysis.

Lower vertebrates like fish exhibit tremendous diversity in sex determination. There are wide interplays between environment-dependent sex differentiation ranging from natural hermaphroditism to sex reversal and genetic sex determination. Diverse systems of male and female heterogamety coexist in fish and sex chromosomes are rarely distinguishable in morphology. Here we show that the spiny eel ((Mastacembelus aculeatus) of the Perciformes, has evolved highly heteromorphic X and Y chromosomes. The metacentric X and Y chromosomes are the largest among 24 homologous pairs, differ from each other in size and morphology, and become distinct after C-banding because of conspicuous heterochromatin blocks which exhibit alternate distribution around the centromeric region. Chromosome painting using probes from the microdissected X chromosome revealed sequence homology between X and Y. During the pachytene stage of meiosis the X and Y form a bivalent. However, their synapsis is delayed which is particularly evident in one terminus. Therefore, the X and Y have resulted from a pericentric inversion in the Y. We conclude that M. aculeatus represents an example of a highly advanced stage of sex chromosome evolution in fish.

Animals↗

PubMed2001

Roles of central interleukin-1 on stress-induced-hypertension and footshock-induced-analgesia in rats.

Central interleukin-1 (IL-1) plays an important role in mediating the neural, endocrine, and behavioral responses to stressors. Here we tested whether central IL-1 is involved in stress-induced hypertension or footshock (FS)-induced-analgesia. We observed that: (1) intracerebral ventricular injection of (ICV) IL-1beta induced pressor responses; (2) hypertension induced by IL-1beta was blocked by ICV an IL-1 antagonist, IL-1ra; (3) ICV IL-1ra attenuated the pressor response induced by FS but intravenous injection of IL-1ra did not significantly reduce this response; (4) the hypertensive response to conditioned fear stimuli was reversed by ICV IL-1ra; (5) FS-induced-analgesia was attenuated by ICV IL-1ra and this effect disappeared 15 min after ICV IL-1ra. These results suggest that both the pressor response to FS or conditioned fear stimuli and short lasting analgesia induced by FS are mediated by central IL-1.

Analgesia↗

PubMed2001

Inhibition of melanoma growth and metastasis by combination with (-)-epigallocatechin-3-gallate and dacarbazine in mice.

(-)-Epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, was shown to have cancer chemopreventive activity. In this study, we examined the antimetastatic effects of EGCG or the combination of EGCG and dacarbazine on B16-F3m melanoma cells in vitro and in vivo. First, the antimetastatic potentials of five green tea catechins were examined by soft agar colony formation assay, and the results show that EGCG was more effective than the other catechins in inhibiting soft agar colony formation. Second, EGCG dose-dependently inhibited B16-F3m cell migration and invasion by in vitro Transwell assay. Third, EGCG significantly inhibited the spread of B16-F3m cells on fibronectin, laminin, collagen, and Matrigel in a dose-dependent manner. In addition, EGCG significantly inhibited the tyrosine phosphorylation of focal adhesion kinase (FAK) and the activity of matrix metalloproteinase-9 (MMP-9). In animal experiments, EGCG alone reduced lung metastases in mice bearing B16-F3m melanomas. However, a combination of EGCG and dacarbazine was more effective than EGCG alone in reducing the number of pulmonary metastases and primary tumor growths, and increased the survival rate of melanoma-bearing mice. These results demonstrate that combination treatment with EGCG and dacarbazine strongly inhibits melanoma growth and metastasis, and the action mechanisms of EGCG are associated with the inhibition of cell spreading, cell-extracellular matrix and cell-cell interactions, MMP-9 and FAK activities.

Animals↗

PubMed2001

Molecular mechanisms of apoptosis induced by magnolol in colon and liver cancer cells.

Magnolol has been reported to have anticancer activity. In this study we found that treatment with 100 microm magnolol induced apoptosis in cultured human hepatoma (Hep G2) and colon cancer (COLO 205) cell lines but not in human untransformed gingival fibroblasts and human umbilical vein endothelial cells. Our investigation of apoptosis in Hep G2 cells showed a sequence of associated intracellular events that included (a) increased cytosolic free Ca(2+); (b) increased translocation of cytochrome c (Cyto c) from mitochondria to cytosol; (c) activation of caspase 3, caspase 8, and caspase 9; and (d) downregulation of bcl-2 protein. Pretreatment of the cells with the phospholipase C inhibitor 1-[6-[[(17 beta)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1 H-pyrrole-2,5-dione (U73122) or the intracellular chelator of Ca(2+) 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA/AM) inhibited the subsequent magnolol augmentation of [Ca(2+)](i) and also the activation of caspase-8 and caspase-9, so that the occurrence of apoptosis in those cells was greatly reduced. Pretreatment of the cells with ZB4 (which disrupts the Fas response mechanism) also decreased the subsequent magnolol-induced caspase-8 activation and reduced the occurrence of apoptosis. We interpreted these findings to indicate that the above-listed sequence of intracellular events led to the apoptosis seen in Hep G2 cells and that [Ca(2+)](i), Cyto c, and Fas function as intracellular signals to coordinate those events.

Antineoplastic Agents, Phytogenic↗

PubMed2001

Application of a progressive-difference method to identify climatic factors causing variation in the rice yield in the Yangtze Delta, China.

Time series of rice yields consist of a technology-driven trend and variations caused by climate fluctuations. To explore the relationship between yields and climate, the trend and temporal variation often have to be separated. In this study, a progressive-difference method was applied to eliminate the trend in time series. By differentiating yields and climatic factors in 2 successive years, the relationship between variations in yield and climatic factors was determined with multiple-regression analysis. The number of hours of sunshine, the temperature and the precipitation were each defined for different intervals during the growing season and used as different regression variables. Rice yields and climate data for the Yangtze Delta of China from 1961 to 1990 were used as a case study. The number of hours of sunshine during the tillering stage and the heading to milk stage particularly affected the yield. In both periods radiation was low. In the first period, the vegetative organs of the rice crop were formed while in the second period solar radiation was important for grain filling. The average temperature during the tillering to jointing stage reached its maximum, which affected rice yields negatively. Precipitation was generally low during the jointing and booting stages, which had a positive correlation with yield, while high precipitation had a negative effect during the milk stage. The results indicate that the climatic factors should be expressed as 20- to 30-day averages in the Yangtze Delta; a shorter or longer period, e.g. 10 or 40 days, is less appropriate.

China↗

PubMed2001

Investigation of the extent of gastric metaplasia in the duodenal bulb by using methylene blue staining.

BACKGROUND AND AIMS: The existence of gastric metaplasia (GM) of the duodenal mucosa has been considered to be highly related to the recurrence of duodenal ulcers (DU). The aims of this study are to evaluate the usefulness of methylene blue staining in the detection of GM, and to clarify the relationship between GM and the deformity of the duodenal bulb. METHODS: Fifteen patients with healed DU and four patients with symptoms of dyspepsia without evidence of ulcers were enrolled into this endoscopic study. During each endoscopy, methylene blue was sprayed evenly on the duodenal bulb, and biopsies were taken from blue-stained and unstained areas. The existence and extent of GM were assessed histologically and grossly. The correlation between duodenal bulb deformity and the extent of GM was also studied. RESULTS: The mean score of methylene blue non-staining (MBNS) was 0, 1.30 +/- 0.15, and 3.00 +/- 0.00 in group A (non-ulcer patients), group B (patients with healed DU and with normal-shaped bulb) and C (patients with healed DU and with deformed duodenal bulb), respectively; showing significant differences among the groups (P < 0.05 in each). Both the existence and the grading of GM were higher in unstained specimens than in blue-stained specimens (100 vs 16.6%, P < 0.0001 and 3.62 +/- 0.09 vs 0.19 +/- 0.06, P < 0.001, respectively). CONCLUSIONS: Methylene blue non-staining can be applied to investigate the existence and extent of GM in the duodenal bulb accurately. The incidence of GM in the duodenal bulb was higher in patients with healed ulcers than in non-ulcer patients. Patients with deformed duodenal bulbs have a higher extent of GM than those without deformed duodenal bulbs.

Adult↗

PubMed2001

[Painting the chromosomes of fishes with human sex chromosome-specific DNA probes].

Chromosome painting is one of the effective methods in studying the evolution of genomes. The chromosomes of the species of fishes--M. aculeatus, M. albus and D. rerio were painted respectively with human X and Y chromosome-specific DNA probes. The results showed that some homologous segments of human X chromosome were found in the genomes of all the three kind of fishes, all the segments were scattered on several pairs of homologous chromosomes in each kind of fish. But no homologous segment of the human Y chromosome was found.

Animals↗

PubMed2001

Relationship of duodenal ulcer recurrence to gastric metaplasia of the duodenal mucosa and duodenal bulb deformity.

BACKGROUND AND PURPOSE: This study investigated changes in the severity of gastric metaplasia (GM) of the duodenal mucosa before and after ulcer healing and Helicobacter pylori eradication. It also investigated whether deformity of the duodenal bulb affects the severity of GM and the likelihood of ulcer recurrence. METHODS: Eleven patients were consecutively enrolled in this study. They all had duodenal ulcer(s) and H. pylori infection, for which they had received anti-H. pylori triple therapy during the active ulcer stage, and had all undergone serial endoscopic examinations during both the active ulcer and scarring ulcer stages, and at 1 year after ulcer healing. Duodenal biopsies were obtained at each endoscopy to identify the severity of GM. Duodenal ulcers were divided into three types by bulbar shape and GM was classified into four grades of severity. RESULTS: All 11 patients had increased GM severity just after ulcer healing. The 1-year follow-up study revealed that the GM was unchanged in six of eight patients with grade 3 GM severity at the scarring stage, while in the other two it regressed to grade 1 or 2; these two patients suffered ulcer recurrence. A markedly deformed bulb (type III) was found in three patients, of whom two had ulcer recurrence. CONCLUSION: Two characteristic conditions were found in patients with duodenal ulcer recurrence after H. pylori eradication: a markedly deformed bulb with grade 3 GM at the scarring stage, and a change in GM from high to low grade at or around the previous ulcer site after ulcer healing.

Adult↗

PubMed2001

[Effects of baicalin on hepatocyte apoptosis induced by TNF-alpha and act D in rats].

OBJECTIVE: To study the effects of baicalin on rat hepatocyte apoptosis induced by tumor necrosis factora (TNF-alpha) and actinomycin D (Act D) in vitro. METHODS: Hepatocytes were cultured with different concentrations of baicalin and the cell apoptosis was induced by TNF-alpha and Act D in vitro. After culturing for 24 h, the activity of hepatocysts was examined by MTT assay and the function of hepatocytes for secreting albumin was detected by bromocresolum Viride method. Agarose gelelectrophoresis and flow cytometric analysis were used to determine the apoptotic cells. RESULTS: The actively of the hepatocyte (A) and content of albumin (ALB) in the supernatant of cultured cells in the groups of 0.2 microgram.ml-1 and 2.0 micrograms.ml-1 of baicaline were significantly higher than those in apoptotic model group (A: P < 0.01; ALB: P < 0.01); respectively Even the ALB value in the group of 0.2 microgram.ml-1 baicalin was higher that of black control group (P < 0.01); The clear "ladder-like" streak-band of DNA fragments was found only in the apoptosis model group by the agarose gel electrophoresis. The flow cytometry showed that all the apoptosis rates in the three baicalin groups were lower than that of the apoptotic model group (P < 0.01). CONCLUSION: Baicaline can restrain rat hepatocyte apoptosis induced by TNF-alpha and ActD in vitro.

Animals↗

PubMed1999

The isolation results and the antimicrobial agents susceptibility analysis of Haemophilus from the sputum of the elderly suffering from respiratory tract disease.

OBJECTIVE: To inform the isolation and antibiotics susceptibility results of Haemophilus in the sputum of old men suffering from respiratory tract disease so that the epidemiological information and treatment can be available to physicians. METHODS: Two groups-group A, patients=562, group B, healthy volunteers=57 expectorated specimens of sputum were cultured with a special medium for Haemophilus. The isolates were then identified with API NH Identification plates and detected with ATB NH antibiotics susceptibility cards, finally, we got the statistics data of Haemophilus species and antibiotics susceptibility rates from Datatrac statistic system of VITEK 32. RESULTS: Haemophilus were detected in 132 specimens out of 562 (23.5%), which includes 6 strains of H. influenzae (4.5%). 122 strains of H. parainfluenzae, 4 strains of H. aphrophilus (3.1%). At the same time, 3 strains of Haemophilus were isolated from group B. Following are the susceptibility rates of sixteen antibiotics of 132 strains of Haemophilus, 73.4% to amoxicillin, 92.4% to amoxicillin and clavulanic acid, 83.3% to cefactor, 90.9% to cefotaxime, 79.5% to cefuroxime-axetil, 52.3% to kanamycin, 25.0% to gentamycin, 72.0% to spectinomycin, 79.5% to chloramphenicol, 50.0% to tetracycline, 9.1% to erythromycin, 42.4% to pristhomycin, 49.2% to rosoxacin, 62.96% to pefloxacin, 97.7% to rifampin, 33.3% to sulfonamides. CONCLUSION: There is a high isolation rate of Haemophilus in the sputum of the elderly suffering from respiratory tract diseases, The H. parainfluenzae is the main Haemophilus in our area of study, which it deserves good attention by clinical microbiological laboratory. In addition, the antibiotics susceptibility results indicate that this species is more susceptible to beta-lactams antibiotics and is less susceptible to some others such as macrolides and aminoglycosides, etc. So, the drug treatment should be based on these antibiotics susceptibility results in order to guide the specific therapy.

Aged↗

PubMed1998

The nematode degenerin UNC-105 forms ion channels that are activated by degeneration- or hypercontraction-causing mutations.

Nematode degenerins have been implicated in touch sensitivity and other forms of mechanosensation. Certain mutations in several degenerin genes cause the swelling, vacuolation, and death of neurons, and other mutations in the muscle degenerin gene unc-105 cause hypercontraction. Here, we confirm that unc-105 encodes an ion channel and show that it is constitutively active when mutated. These mutations disrupt different regions of the channel and have different effects on its gating. The UNC-105 channels are permeable to small monovalent cations but show voltage-dependent block by Ca2+ and Mg2+. Amiloride also produces voltage-dependent block, consistent with a single binding site 65% into the electric field. Mammalian cells expressing the mutant channels accumulate membranous whorls and multicompartment vacuoles, hallmarks of degenerin-induced cell death across species.

Amiloride↗

PubMed1998

Alcohol-related problems in Taiwan with particular emphasis on alcoholic liver diseases.

Socioeconomic development has led to a progressive increase of alcohol consumption in Taiwan, with an accompanying increase in alcohol-related psychiatric problems, traffic accidents, and liver disease. The prevalent rates of alcohol dependence for Han Chinese and Fomosan aborigines were 0.1% and 1%, respectively in 1950. The rate of alcohol dependence increased to 23% for aborigines in 1995. The number of cases of death and serious injuries due to alcohol-related traffic accident has decreased, and the number of fatalities resulting from these accidents has decreased from third to eighth since the inception of a program of random traffic stops with alcohol breath test in 1997. Alcohol liver disease (ALD) was defined as daily alcohol consumption of 60 g, for a duration of longer than 5 years. We classified ALD patients into two groups: (1) those whose average daily consumption of alcohol exceeded 120 g for a duration longer than 15 years (group A); and (2) all other patients (group B). The case records of 33 cases of biopsy-confirmed ALD were obtained for study. The average of daily alcohol consumption in these cases was 160 g. All but one of these patients were male, age ranged from 26 to 69 years, with an average of 43.1. Clinically, ill-defined gastrointestinal symptoms were the most common presentation (61%), and hepatomegaly was the main physical sign (73%). The average mean corpuscular volume values of ALD and non-ALD patients were 102.3 +/- 10.94 and 94.5 +/- 8.1, respectively (p < 0.01). The mean corpuscular volume values of group A and group B were 102.9 +/- 9.7 vs. 96.5 +/- 9.11 (p < 0.05). Result from serum SGOT/SGPT and gamma-glutamyltransferase/alkaline phosphatase for ALD and non-ALD revealed statistically significant differences between these groups. Using the avidin-biotin complex technique, tissue IgA deposition for ALD patients was found to be different from that of non-ALD patients. Ten of 13 ALD patients vs. 2 of 13 non-ALD patients had continuous-form IgA deposition. Histologically, 45.5% of ALD patients had alcoholic cirrhosis, whereas alcoholic hepatitis was present in only 9.1% of patients. Overall, 88% of cases showed various severity of fatty metamorphosis.

Adult↗

PubMed1998

Case report: Spontaneous isolated mesenteric fibromatosis presenting as megaduodenum.

A case of spontaneous isolated mesenteric fibromatosis presenting as megaduodenum is reported. The lesion was small, only 2 cm in its greatest diameter. However, because of its location near the ligament of Treitz and because of its characteristic infiltrative growth pattern, the tumour involved the distal duodenum and resulted in acute angulation and obstruction early in its course. We successfully resected the mass and the patient is in fair physical condition 6 months after operation.

Adult↗

PubMed1997

Double filtration plasmapheresis for the treatment of rheumatoid arthritis: a study of 21 cases.

The treatment of rheumatoid arthritis remains difficult and often controversial. Plasma exchange has been advocated in some cases. In the present study 71 sessions of double filtration plasmapheresis (DFPP) were performed in 21 patients with rheumatoid arthritis in an average of 3.7 +/- 1.1 sessions per patient within 1-2 weeks. Seven patients had received prednisone, and all the patients had received nonsteroid anti-inflammatory drugs with poor results. Although after the DFPP therapy, only 2 patients were still receiving nonsteroid anti-inflammatory drugs, the function capacities improved in all patients. Five out of 8 positive rheumatoid factors became negative for the group. These results suggest that DFPP could be a regular therapy for rheumatoid arthritis.

Adolescent↗

PubMed1996

Polymerase chain reaction diagnosis of Helicobacter pylori in gastroduodenal diseases: comparison with culture and histopathological examinations.

Helicobacter pylori has been associated with a variety of upper gastrointestinal diseases. Histopathological examination and culture are considered to be the more specific tests in the diagnosis of H. pylori infection. In the present study, we evaluated the efficiency of a polymerase chain reaction (PCR) assay of the H. pylori urease A gene as a procedure in the diagnosis of gastric H. pylori infection in various gastroduodenal diseases. Biopsy specimens were obtained from the antral mucosa of 83 patients during endoscopic examination and were submitted to three tests for the detection of H. pylori infection. The detection rates of H. pylori using PCR, histopathological examination and culture were 84, 77 and 63%, respectively. When the infection was defined, by the agreement of culture and histopathological examination or by positive culture, the PCR assay had a sensitivity of 98.1% and a specificity of 84.6%. When the infection was defined by a positive result of either two of the three tests or by positive culture, the PCR assay had a sensitivity of 98.6% and a specificity of 85.7%. We conclude that the PCR assay is a valuable test for the diagnosis of H. pylori infection in gastroduodenal diseases.

Adult↗

PubMed1996

Salmonella infections: a retrospective 10-year analysis of 134 cases in a regional hospital in Taiwan.

A total of 134 cases of salmonella infections have been noted during the past 10 years in our hospital. Cases of non-typhoidal salmonellosis increased gradually but infections due to Salmonella typhi did not show the same trend. Gastroenteritis was the most prevalent diagnosis in patients below 1 year of age and non-typhoidal bacteraemia and localized infections were the most prevalent in patients over 50 years. Diabetes mellitus was an important underlying disease especially in patients with localized infections (86%). Travelling history played an important role in cases of enteric fever. The susceptibility pattern in non-typhoidal salmonella changed markedly over the study period; multiple drug resistance was noted. The susceptibility pattern of S. typhi showed no significant change. Seven deaths due to salmonella infections were noted (5.2%); all due to non-typhoidal salmonellosis, especially serogroup B. Age above 50 years, localized infection, infection with serogroup B and diabetes were poor prognostic factors.

Adolescent↗

PubMed1995

Drug-induced liver disease--a review of 14 cases.

The clinical and pathological features of 14 cases of acute drug-induced liver disease (DILD) were analyzed using the French group method for drug reaction assessment. Among them, 8 were of the cytotoxic type, 4 were of the cholestatic type and 2 were of the mixed type. Serum alkaline phosphatase (ALP) levels of the cytotoxic type DILD were all < 1.8 times the normal value, while those of the cholestatic type DILD > 1.8 times (P < 0.05). The alanine aminotransaminase and aspartate aminotransaminase (ALT and AST) levels of the cholestatic type were all < 13.1 times the normal value, while those of the cytotoxic type varied from 2.2 to 118 times the normal value. We found that steatosis was the major feature in the cytotoxic type with ALT and AST < 2.5 times the normal value. Piecemeal necrosis was noted only in all the cases with ALT and AST > 20 times the normal value. In the cholestatic type, the pathological features of the oral contraceptive-related DILD showed mainly cholestasis, whereas chlorpromazine-related DILD revealed additional portal inflammation. Meticulous taking of patient history and clinical assessment are mandatory for the diagnosis of DILD. The ALP levels were helpful in distinguishing different types of DILD. There are some correlations between biochemical changes and pathological features, and both are helpful in distinguishing different etiologies of DILD when the inciting drug is in doubt.

Adult↗