PubMed Health⌕ Search

Biomedical subjects

H F Lu

Publications and source records attributed to H F Lu.

At least 19 recordsLinked to original sources
PubMed2004

Diallyl disulfide (DADS) induced apoptosis undergo caspase-3 activity in human bladder cancer T24 cells.

Diallyl disulfide (DADS), one of the major components of garlic (Allium sativum), is well known to have chemopreventative activity against human cancer such as colon, lung and skin. But the exact mechanism of the action is still unclear. In this study, we investigated how DADS--induced cell cycle arrest and apoptosis in T24 human bladder cancer cells in vitro. Apoptosis induction, cell viability, cell cycle arrest, caspases-3, -9 activity and gene expression were measured to determine their variation by flow cytometric assay, western blot, and determination of caspase-3 activity, PCR and cDNA microarray. There are significant differences in cell death (decreased viable cells then increased the amounts of apoptosis) of T24 cells that were detected between DADS (5-75 microM) treated and untreated groups. A significant increase was found in apoptosis induction when cells were treated with DADS (50 microM) compared to without DADS treated groups. DADS also promoted caspase-3 activity after exposure for 1, 3, 6, 12, and 24 h, which led to induce apoptosis. DADS also increased the product of intracellular hydrogen peroxide. Furthermore, the DADS-induced apoptosis on T24 cells was blocked by the broad-spectrum caspase inhibitor, z-VAD-fmk and antioxidant (catalase). DADS also increased cyclin E and decreased CDK2 gene expression which may lead to the G2/M arrest of T24 cells.

Allyl Compounds↗
PubMed2004

Inhibition of N-acetyltransferase activity and gene expression in human colon cancer cell lines by diallyl sulfide.

Diallyl sulfide (DAS) is one of the major components of garlic (Allium sativum) and is widely used in the world for food. In this study, DAS was selected for testing the inhibition of arylamine N-acetyltransferase (NAT) activity (N-acetylation of 2-aminofluorene) and gene expression (mRNA NAT) in human colon cancer cell lines (colo 205, colo 320 DM and colo 320 HSR). The NAT activity was examined by high performance liquid chromatography and indicated that a 24 h DAS treatment decreases N-acetylation of 2-aminofluorene in three colon (colo 205, 320 DM and colo 320 HSR) cancer cell lines. The NAT enzymes (protein) were analyzed by western blotting and flow cytometry and it indicated that DAS decreased the levels of NAT in three colon (colo 205, 320 DM and colo 320 HSR) cancer cell lines. The gene expression of NAT (mRNAT NAT) was determined by polymerase chain reaction (PCR), it was shown that DAS affect mRNA NAT expression in examined human colon cancer cell lines. This report is the first to demonstrate that DAS does inhibit human colon cancer cell NAT activity and gene expression.

Allyl Compounds↗
PubMed2002

The effect of paclitaxel on 2-aminofluorene-DNA adducts formation and arylamine N-acetyltransferase activity and gene expression in human lung tumor cells (A549).

In this study, paclitaxel was used to determine inhibition of arylamine N-acetyltransferase (NAT) activity, gene expression and 2-aminofluorene-DNA adduct formation in a human lung tumor cell line (A549). The activity of NAT was measured by HPLC assaying for the amounts of N-acetyl-2-aminofluorene (2-AAF) and remaining 2-aminofluorene (2-AF). Human lung tumor cell cytosols and intact cells were used for examining NAT activity and carcinogen-DNA adduct formation. The results demonstrated that NAT activity, gene expression (NAT1 mRNA) and 2-AF-DNA adduct formation in human lung tumor cells were inhibited and decreased by paclitaxel in a dose-dependent manner. The effects of paclitaxel on the values of the apparent Km and Vmax of NAT from human lung tumor cells were also determined in both examined systems. The result also indicated that paclitaxel decreased the apparent values of Km and Vmax from human lung tumor cells in both cytosol and intact cells. Thus, paclitaxel is an uncompetitive inhibitor to NAT enzyme.

Acetylation↗
PubMed2001

Arginine form of p21 gene codon 31 is less prominent in patients with calcium oxalate stone.

The formation of urinary stones is associated with cell death in response to various injuries. P21 (WAF1/CIP1) is a downstream protein of P53 and can arrest the cell cycle at G1/S with resulting cell death. We aimed to investigate the polymorphism of p2 gene codon 31 as the genetic marker in searching for the association of urolithiasis. One hundred and nineteen healthy controls and 95 patients with calcium oxalate stone were examined in this study. The polymorphism was seen from the result of polymerase chain reaction-based restriction analysis. The result revealed significant differences between normal individuals and stone patients (P < 0.05) and the distribution of arginine homozygote in the control group (31.9%) was higher than in the patient group (16.8%). It is concluded that polymorphisms of p21 codon 31 can be a genetic marker for urinary stone disease. Individuals possessing arginine form of p21 codon 31 have less risk of developing calcium stone disease.

Adult↗
PubMed2001

Lack of evidence for the association of tumor necrosis factor-alpha gene promoter polymorphism with calcium oxalate stone and bladder cancer patients.

Urinary stone disease and bladder cancer are two of the most commonly seen urologic diseases in Taiwan. Tumor necrosis factor-alpha (TNF-alpha) is one of the cytokines secreted by macrophages and is related to a sequence of events in response to inflammation and cancer formation. We investigated the polymorphism of the TNF-alpha gene promoter -308 as a genetic marker in searching for the association between these two commonly seen urologic diseases. One hundred and fourteen patients with transitional cell carcinoma of the urinary bladder and 103 patients with calcium oxalate stone were compared with 150 healthy controls. The polymorphism was detected by polymerase chain reaction-based restriction analysis (Nco I endonuclease). The results revealed no significant differences between normal individuals and the patients with the two commonly seen urologic diseases (P > 0.05). We concluded that the polymorphism of the TNF-alpha promoter -308 is not a valid genetic marker for these two urologic diseases.

Adult↗
PubMed2001

Association of the vitamin D receptor gene start codon Fok I polymorphism with calcium oxalate stone disease.

OBJECTIVE: To assess the use of Fok I polymorphism (the most frequent polymorphism, at the start codon of the vitamin D receptor gene, VDR) as a convenient genetic marker in identifying the cause of urolithiasis. PATIENTS, SUBJECTS AND METHODS: A normal control group of 90 healthy subjects and 146 patients with calcium oxalate stones were examined. Using polymerase chain reaction (PCR)-based restriction analysis, the relationship between Fok I polymorphism and urolithiasis was evaluated. An unexcisable length of 265 bp was identified (allele CC) and two fragments (169 bp and 96 bp) identified as excisable lengths (allele TT). RESULTS: There was a statistically significant difference between the groups (chi-square test, P < 0.05) for the genotype of the VDR Fok I start codon polymorphism. The odds ratio (95% confidence interval) for the C allele in those at risk of stone disease was 1.672 (1.149-2.432). CONCLUSIONS: These results suggest that the VDR Fok I start codon polymorphism may be a good candidate for a genetic marker in calcium oxalate stone disease.

Adult↗
PubMed2001

Calcitonin receptor gene polymorphism: a possible genetic marker for patients with calcium oxalate stones.

OBJECTIVES: The formation of urinary stones is hypothesized to be associated with calcitonin receptors. The most commonly seen polymorphism is C/T at the 1377th nucleotide. Hence, these polymorphisms are being used as a genetic marker in the search for the cause of urolithiasis. METHODS: A normal control group of 105 healthy people and 102 patients with recurrent calcium oxalate stones were examined. The polymorphism was detected following a polymerase chain reaction-based and restriction analysis by AluI. An uncuttable length is 228 bp (CC) whereas two fragments of 120 and 108 bp are shown as cuttable lengths (TT). RESULTS: The results revealed significant differences between the normal individuals and the stone patients (p<0.01). The distribution of leucine (cuttable) homozygote in the stone group (2.0%) was higher than in the control group (0.0%). The odds ratio for the leucine allele of the calcitonin receptor gene in calcium oxalate stone disease is 5.634 (95% CI: 2.286--13.885). CONCLUSIONS: Results show that the polymorphism in the calcitonin receptor gene could be a genetic marker for urinary stone disease and therefore it is worthwhile pursuing further studies of the leucine allele of calcitonin receptor gene due to it is strongly correlated with stone disease.

Adult↗
PubMed2001

Clinicopathological and molecular genetic analysis of 4 typical Chinese HNPCC families.

AIM: To study the clinicopathological and molecular genetic characteristics of typical Chinese hereditary nonpolyposis cotorectal cancer (HNPCC) families. METHODS: Four typical Chinese HNPCC families were analyzed using microdissection, microsatellite instability analysis, immunostaining of hMSH2 and hMLH1 proteins and direct DNA sequencing of hMSH2 and hMLH1 genes. RESULTS: All five tumor tissues of 4 probands from the 4 typical Chinese HNPCC families showed microsatellite instability at more than two loci (MSI-H or RER+ phenotype). Three out of the 4 cases lost hMSH2 protein expression and the other case showed no hMLH1 protein expression. Three pathological germline mutations (2 in hMSH2 and 1 in hMLH1), which had not been reported previously, were identified. The same mutations were also found in other affected members of two HNPCC families,respectively. CONCLUSION: Typical Chinese HNPCC families showed relatively frequent germline mutation of mismatch repair genes. High-level microsatellite instability and loss of expression of mismatch repair genes correlated closely with germline mutation of mismatch repair genes. Microsatellite instability analysis and immunostaining of mismatch repair gene might serve as effective screening methods before direct DNA sequencing. It is necessary to establish clinical criteria and molecular diagnostic strategies more suitable for Chinese HNPCC families.

Adult↗
PubMed2001

Correlation of unilateral urolithiasis with sleep posture.

PURPOSE: Recurrent stone formers commonly present with calculi on the same side and the etiology of recurrent unilateral urolithiasis is unclear. Despite comprehensive metabolic evaluations, many patients will not be readily categorized into a treatable group. Data from the literature support that sleep posture may result in alterations of renal hemodynamics. We investigate the correlation of sleep posture with unilateral urinary stone formation. MATERIALS AND METHODS: A prospective study of 110 patients with recurrent unilateral nephrolithiasis was conducted. A questionnaire was used to evaluate patient sleep posture. Right or left side down and rotisserie-like sleep postures were defined. The side of stone formation was correlated with sleep posture using chi-square test. RESULTS: Of the patients 93 slept consistently with 1 side in a dependent position and the side of stone was identical to the dependent sleep side in 76% (p = 0.008). The positive predictive values of right and left side down sleep posture for formation of ipsilateral calculi were 82% and 70%, respectively. CONCLUSIONS: Although the exact pathophysiology of the association between sleep posture and recurrent unilateral stone disease remains to be elucidated, sleep posture may alter renal hemodynamics during sleep and promote stone formation. This observation needs further investigation and should be factored into the evaluation and prevention of unilateral urinary stone disease.

Adult↗
PubMed2001

Luteolin inhibits the growth and arylamine N-acetyl-transferase activity in Neisseria gonorrhoeae.

Growth inhibition and arylamine N-acetyltransferase (NAT) activity in Neisseria gonorrhoeae were inhibited by luteolin, a drug which originated from herbs. The growth inhibition was based on changes in optical density (OD) using a spectrophotometer, and arylamine NAT activity with 2-aminofluorene (2-AF) was determined using high pressure liquid chromatography. The inhibition of growth in N. gonorrhoeae demonstrated that luteolin elicited a dose-dependent growth inhibition in the N. gonorrhoeae cultures. Suspensions of N. gonorrhoeae with or without specific concentrations of luteolin cotreatment showed different percentages of 2-AF acetylation. The data indicated that there was reduced NAT activity associated with increased levels of luteolin in N. gonorrhoeae suspensions. Time-course experiments showed that NAT activity measured from intact N. gonorrhoeae cells was inhibited by luteolin for at least 4 h. Using standard steady-state kinetic analysis, it was demonstrated that luteolin was a possible uncompetitive inhibitor to NAT activity in N. gonorrhoeae. This report is the first to show that luteolin can inhibit N. gonorrhoeae NAT activity.

Arylamine N-Acetyltransferase↗
PubMed2001

Transperitoneal preperitoneal laparoscopic lumbar incisional herniorrhaphy.

PURPOSE: Flank incisions may be associated with flank hernias, which may be complicated by incarceration and strangulation. Furthermore, they may be the cause of significant patient dissatisfaction with the surgical outcome. To avoid an open surgical procedure with its associated morbidity for hernia repair we describe a novel laparoscopic technique for repairing flank hernias with minimal morbidity and an excellent outcome. MATERIALS AND METHODS: Three cases of flank hernia were managed by the transperitoneal preperitoneal laparoscopic approach using polypropylene mesh to repair the fascial defect. An initial transperitoneal approach helps to identify the limits of the hernia. A 2 to 3 cm. margin of overlying peritoneum is incised around the hernia margin. It is important not to dissect overlying bowel. The mesh is placed behind the peritoneal envelope and secured with hernia staples. RESULTS: All cases were managed successfully via laparoscopy. There were no intraoperative or postoperative complications. At a mean followup of 12 months cosmesis has been excellent and there have been no recurrences. CONCLUSIONS: We describe a minimally invasive, versatile technique for laparoscopic repair of flank incisional hernias with excellent functional and cosmetic results. This approach avoids the significant morbidity associated with open repair of incisional flank hernias.

Adult↗
PubMed2001

Factors affecting the recovery of Legionella pneumophila serogroup 1 from cooling tower water systems.

A total of 20 water samples collected from the cooling towers at 20 different sites were analyzed under various conditions for the presence of Legionella pneumophila serogroup 1. A comparative assessment was performed to evaluate methods of sample collection (spray drops, beneath water at 20- to 40-cm depth, and water outlet), concentration (filtration and centrifugation), acid buffer treatment (no treatment, treatment for 3, 5, and 15 min), and CO2 incubation or candle jar incubation. The reduction in viable colonies and false negative rate were compared for the different factors. No quantitative differences in isolation of L. pneumophila serogroup 1 was found among samples collected from water at a depth of 20 to 40 cm, from water outlet, and from spray drops. Treatment in an acid buffer for 15 min significantly reduced the recovery rate, with a reduction in bacterial counts of about 40%, compared with a 3-min (12%) or a 5-min (25%) treatment. Acid buffer treatment for 3 or 5 min reduced the overgrowth of commensal flora. This treatment improved the selectivity but not the sensitivity for L. pneumophila serogroup 1. Colonies on plates incubated at 37 degrees C in a candle jar with a humidified atmosphere grew better than those incubated at 35 degrees C with 5% CO2. These results demonstrate that methods of sample collection, concentration, and incubation, but not collection site, can affect the isolation rate for L. pneumophila serogroup 1.

Air Conditioning↗
PubMed2001

Laparoscopic nephrectomy for inflammatory renal conditions.

PURPOSE: Inflammatory and infectious renal conditions may result in severe perirenal fibrosis, making the laparoscopic approach challenging. The theoretical advantages of laparoscopy for managing inflammatory and infectious renal conditions have been questioned. We identified whether laparoscopy for inflammatory renal conditions is associated with higher morbidity than for other benign renal conditions. Furthermore, several technical modifications are discussed that may help to improve the outcome. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients who underwent laparoscopic nephrectomy for inflammatory and infectious renal conditions between 1998 and 2000. The transperitoneal approach was used and specimens were removed after morcellation. Operative data were compared with those from a similar group of patients who underwent laparoscopic nephrectomy for other benign conditions. RESULTS: Laparoscopic nephrectomy done for inflammatory or infectious conditions in 12 cases and for other benign conditions in 9 matched cases was completed successfully in 10 (83%) and 9 (100%), respectively. In the inflammatory and benign groups mean blood loss plus or minus standard deviation was 155 +/- 163 and 59 +/- 23 ml. (p = 0.099), mean operative time was 284 +/- 126 and 226 +/- 62 minutes (p = 0.225), and mean postoperative hospital stay was 4.1 +/- 2 and 3 +/- 1 days (p = 0.157), respectively. CONCLUSIONS: Laparoscopic nephrectomy can be performed safely in most cases of inflammatory renal conditions. Although they were not statistically significant, a higher conversion rate and longer operative time should be expected. Early conversion may be required due to failure to progress. Similar advantages were observed in patients with inflammatory and other benign renal conditions via the laparoscopic approach.

Adult↗
PubMed2000

Distributions of p53 codon 72 polymorphism in bladder cancer--proline form is prominent in invasive tumor.

Abnormal function of p53 is commonly associated with various cancer formations. High-grade and late-stage bladder cancers have been reported to have mutated or become inactive p53 when using immunohistochemical stains. Recently, p53 codon 72 polymorphism was extensively studied to determine the risk factors responsible for cancer formation. There was a general population of codon 72 sequence polymorphism of the wild type p53. A single base change from G to C caused the alteration of amino acid residue 72 from arginine to proline. The arginine form is considered to be a significant risk factor in the development of cancer. However, various reports had indicated discrepancies with regard to this polymorphism; some showed no significant difference between the control and cancer groups, while other series were associated with high risks in the proline form homozygotes. To resolve the undefined distribution of this polymorphism in bladder cancers, 58 patients with bladder cancer were enrolled onto this study. When checked using the Chi-squared test (P = 0.952) there were no differences between the control subjects and bladder cancer patients in the distribution of polymorphism. However, proline form homozygotes were more frequently found in the invasive group than the non-invasive group by Fisher's exact test (25% and 2.9%, respectively, P < 0.001). More than 70% of the non-invasive bladder cancers were the arginine form homozygotes. This result is consistent with those reported for hepatocellular carcinoma that showed a history of chronic liver disease and proline form homozygotes in a report by Yu et al. Our data suggest that proline form homozygotes are associated with invasive bladder cancer.

Adult↗
PubMed2000

Inhibition by vitamin C of DNA adduct formation and arylamine N-acetyltransferase activity in human bladder tumor cells.

Previous studies have already demonstrated the protective role of vitamin C (ascorbic acid) in certain types of cancer. This study reports on the effects of vitamin C on arylamine N-acetyltransferase (NAT) activity and DNA adduct formation in a human bladder tumor cell (T24) line. The activity of NAT was measured using high-performance liquid chromatography (HPLC), by assaying for the amounts of acetylated 2-aminofluorene (AF) and p-aminobenzoic acid (PABA) and the remaining amounts of AF and PABA. T24 cells were used for examining NAT activity and carcinogen DNA adduct formation. The results demonstrated that NAT activity and 2-aminofluorene DNA adduct formation in T24 cells were inhibited and decreased by vitamin C in a dose-dependent manner. The apparent kinetic parameters (apparent values of Km and Vmax) from T24 cells were also determined with and without vitamin C cotreatment. The data also indicated that vitamin C decreased the apparent values of Km and Vmax from T24 cells.

4-Aminobenzoic Acid↗
PubMed2000

Cryopreservation of mature human oocytes by vitrification with ethylene glycol in straws.

OBJECTIVE: To examine the effect of vitrification with ethylene glycol (EG) for mature human oocytes in straws. DESIGN: Prospective, randomized, in vitro experiments. SETTING: Reproductive unit of a university hospital. PATIENT(S): Immature oocytes from 110 patients undergoing intracytoplasmic sperm injection (ICSI). INTERVENTION(S): The immature oocytes were incubated to reach metaphase II (MII). The MII oocytes were treated with EG-based cryoprotectants and vitrified in straws. They were diluted in sucrose solutions, inseminated by ICSI, and cultured in vitro. MAIN OUTCOME MEASURE(S): Survival, fertilization, and embryo cleavage. RESULT(S): The survival rates were greater for oocytes pretreated with 1.5 M of EG (65% for 0 minute, 93% for 5 minutes, and 96% for 10 minutes). The oocytes vitrified in 60 and 90 seconds had a greater rate of fertilization than those vitrified in 120 seconds. There were no differences in survival and fertilization for vitrified oocytes diluted by three or four steps. The cleavage rates to the six- to eight-cell stage were comparable with controls. However, no blastocyst formation was observed in vitrified oocytes. CONCLUSION(S): Vitrification of human oocytes with EG in straws achieves a high rate of survival, fertilization, and early cleavage of embryos. Further studies should be conducted for the improvement of blastocyst formation.

Cell Survival↗
PubMed2000

Value of serum and follicular fluid cytokine profile in the prediction of moderate to severe ovarian hyperstimulation syndrome.

The aim of this study was to examine the role of serum and follicular fluid pro-inflammatory cytokines and vascular endothelial growth factor (VEGF) in the prediction of ovarian hyperstimulation syndrome (OHSS). A total of 156 consecutive women undergoing in-vitro fertilization were recruited. The study group comprised 12 women who subsequently developed moderate (n = 7) or severe (n = 5) OHSS. The two control groups were comprised of a randomized selection of 12 high-risk and 12 low-risk women in whom OHSS did not develop. Serum was collected on days of human chorionic gonadotrophin, oocyte retrieval, and embryo transfer. Serum and follicular fluid concentrations of interleukin (IL)-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), and VEGF were measured. Follicular fluid IL-6 concentrations at the time of oocyte retrieval and serum IL-8 concentrations at the time of embryo transfer were significantly higher in the OHSS compared to the two control groups (P = 0.026 and P = 0.017 respectively). Serum concentrations of TNF-alpha and VEGF showed no statistically significant difference between the OHSS group and the controls at any studied time point. This study suggests that follicular fluid IL-6 concentrations at the time of oocyte retrieval and serum IL-8 concentrations on the day of embryo transfer may serve as early predictors for this syndrome.

Adult↗