Biomedical subjects
Publications and source records attributed to J F Lee.
A series of 5-[(3,5-bis(trifluoromethyl)phenyl)methoxy]-3-(3,4-dichlorophenyl)-4(Z)- (methoxyimino)pentyl-1-piperazines was prepared and their affinity for the NK1 and NK2 receptors investigated. Compounds 7f, 10o, 10r, and 10s were found to be our most potent inhibitors.
BACKGROUND: Hepatic blood inflow occlusion during hepatectomy may influence postoperative liver regeneration. The aim of this study was to investigate the influence of hepatic blood inflow occlusion on liver regeneration following partial hepatectomy in thioacetamide-induced cirrhotic rats. METHODS: Forty-three cirrhotic Wistar-Furth rats were randomly assigned to three groups. Rats in group 1 underwent 64 per cent hepatectomy alone, those in group 2 were subjected to 15 min hepatic blood inflow occlusion followed by 64 per cent hepatectomy, and animals in group 3 were subjected to 30 min inflow occlusion followed by 64 per cent hepatectomy. Liver function, 5-bromo-2'-deoxyuridine (BrdU) labelling index and percentage of initial liver weight on days 1, 2 and 7 posthepatectomy were assessed. RESULTS: Rats in groups 1 and 2 had a significantly higher serum albumin level and a markedly lower alanine aminotransferase level than animals in group 3 on day 1 posthepatectomy (P < 0.05). There was no significant difference in the serum level of total bilirubin of the three groups on days 1, 2 and 7. The BrdU labelling index was significantly higher in groups 1 and 2 than in group 3 animals on day 1 posthepatectomy (P < 0.01 and P < 0.05 respectively). Percentages of initial liver weight were similar in groups 1, 2 and 3 on days 1, 2 and 7 after hepatectomy. CONCLUSION: Hepatic blood inflow occlusion for up to 30 min suppressed DNA synthesis and hepatocyte proliferation at an early posthepatectomy stage and consequently delayed recovery of liver function in cirrhotic rats. However, it did not affect restoration of liver mass or survival after 64 per cent hepatectomy.
BACKGROUND: Acute appendicitis in the elderly (i.e. those over 60 years of age) is associated with high morbidity and mortality rates. The present retrospective study reviews 10 years ( 1986-1996) of experience and outcome in treating acute appendicitis in patients aged 60 or above. METHODS: One hundred and thirty patients with acute appendicitis were identified and their case notes reviewed. RESULTS: Acute appendicitis was diagnosed at admission in 84 patients (64.6%). The remaining patients were observed for a median duration of 9.4 h prior to diagnosis and treatment. Patients with an underlying perforated acute appendix had a significantly longer period of pain prior to admission (P = 0.029; Mann-Whitney U-test) but perforation per se was not associated with a significantly higher rate of morbidity and longer length of hospital stay. In contrast, the use of midline or paramedian incisions was associated with a higher wound infection rate (P=0.003; Pearson chi-squared test) and a longer hospital stay (P<0.001; Mann Whitney U-test). None of the patients were subsequently found to have an underlying colonic neoplasm. The overall morbidity rate was 28%. The mortality rate was 2.3% and all three patients who died had a severe comorbid medical condition prior to developing acute appendicitis. CONCLUSIONS: Acute appendicitis in the elderly is still associated with significant morbidity. But once acute appendicitis is diagnosed, then expedient surgery, appropriate use of perioperative antibiotics and a right lower quadrant incision can help to minimize the morbidity. Pre-existing severe comorbid medical condition(s) is a major contributory factor to mortality in these patients.
OBJECTIVE: To compare the systemic cytokine response in patients after laparoscopic-assisted resection with those after open resection of rectosigmoid carcinoma. SUMMARY BACKGROUND DATA: Laparoscopic resection of colorectal carcinoma is technically feasible, but objective evidence of its benefit is scarce. Systemic cytokines are accepted as markers of postoperative tissue trauma and mediators of the host immune response. METHODS: Thirty-four patients with rectosigmoid carcinoma, without evidence of metastatic disease and suitable for laparoscopic resection, were randomized to undergo either laparoscopic (n = 17) or conventional open (n = 17) resection of the tumor. Clinical parameters were recorded. Sera were collected before surgery and at appropriate time points afterward and assayed for interleukin-1beta, tumor necrosis factor-alpha, interleukin-6, and C-reactive protein. The primary end points were the cytokine and C-reactive protein levels. Data were analyzed by intention to treat. RESULTS: The demographic data of the two groups were comparable. The clinical outcome of both groups was satisfactory, with no surgical deaths and a reasonable complication rate. Both interleukin-1beta and interleukin-6 levels peaked 2 hours after surgery, with the responses in the laparoscopic group significantly less than those in the open group. C-reactive protein levels peaked at 48 hours, and the difference was also statistically significant. Levels of tumor necrosis factor-alpha were not elevated after surgery, and there was no difference between the groups. CONCLUSIONS: Tissue trauma, as reflected by systemic cytokine response, was less after laparoscopic resection than after open resection of rectosigmoid carcinoma. The difference in the systemic cytokine response may have implications on the long-term survival.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
BACKGROUND AND OBJECTIVES: Laparoscopic-assisted resection of colorectal carcinoma is technically feasible. Whether it is beneficial to patients is uncertain. This study reviewed the results of laparoscopic-assisted resection in patients with right-sided colonic adenocarcinoma. METHODS: We attempted laparoscopic-assisted right to extended right hemicolectomy in 28 patients with right-sided colonic carcinoma (study group). The results were compared with 56 matched patients who underwent conventional open resection in the same period (comparative group). RESULTS: The median follow-up times for the study and comparative groups were 21.4 and 23.5 months, respectively. The operating time was significantly longer (t-test, P < 0.001), whereas the time to resuming normal diet (Mann-Whitney U-test, P < 0.001) and the duration of hospital stay (Mann-Whitney U-test, P = 0.002) were significantly less in the study than in the comparative group. The oncological clearance, in terms of the number of lymph nodes removed and the resection margins, the complication rate, the disease-free rate, and the survival rate were comparable in the two groups. CONCLUSIONS: We conclude that laparoscopic-assisted resection of right-sided colonic adenocarcinoma has the advantage over open surgery of allowing earlier recovery. However, this is at the expense of a longer operating time.
INTRODUCTION: The place of laparoscopic-assisted colectomy for colorectal carcinoma is controversial. This study reviewed a consecutive series of patients who underwent laparoscopic-assisted resection of colorectal carcinoma in the past five years. METHODS: Two hundred seventeen laparoscopic-assisted resections of colorectal carcinoma were attempted starting in April 1992. Initially, we only selected patients with metastatic disease or patients who were older than 65 years. Subsequently, both palliative and curative resections were attempted in patients with a suitable tumor, with no age limitation. Thus, all suitable patients were randomly assigned to received either laparoscopic-assisted or conventional open surgery. RESULTS: Data collection was completed in 201 patients. In 22 patients open surgery was performed after a diagnostic laparoscopy. In the remaining 179 patients (90 males) in whom laparoscopic dissection was actually performed, the mean follow-up was 19.8 months, and the mean age was 66.3 years. The procedures performed included right hemicolectomy or extended right hemicolectomy (30 patients), transverse colectomy (2 patients), left hemicolectomy (3 patients), sigmoidectomy (48 patients), anterior resection (59 patients), and abdominoperineal resection (37 patients). Thirty-two (17.7 percent) procedures were converted to open surgery. The mean operation time was 203 minutes. The median blood loss was negligible, and the median requirement of transfusion was zero. The median number of postoperative parenteral analgesic injections was three. The median time to resume diet and hospital discharge were four and six days, respectively. The operative mortality was 1.7 percent. The survival rates at four years were 100, 88.3, and 64.5 percent for patients with Dukes A, B, and C disease, respectively. There was only one (0.65 percent) port-site recurrence. CONCLUSION: Laparoscopic-assisted resection of colorectal carcinoma was technically feasible and safe. It allowed early postoperative recovery with satisfactory long-term survival. This is at the expense of a long operation. Its benefits over the conventional open technique await the results of the randomized trials.
An unusual case of solitary breast metastasis from a primary anorectal melanoma in a 59-year-old post-menopausal woman is reported. The course and management of melanotic breast metastases is discussed.
Two of the three class I alcohol dehydrogenase (ADH) genes (ADH2 and ADH3) encode known functional variants that act on alcohol with different efficiencies. Variants at both these genes have been implicated in alcoholism in some populations because allele frequencies differ between alcoholics and controls. Specifically, controls have higher frequencies of the variants with higher Vmax (ADH2*2 and ADH3*1). In samples both of alcoholics and of controls from three Taiwanese populations (Chinese, Ami, and Atayal) we found significant pairwise disequilibrium for all comparisons of the two functional polymorphisms and a third, presumably neutral, intronic polymorphism in ADH2. The class I ADH genes all lie within 80 kb on chromosome 4; thus, variants are not inherited independently, and haplotypes must be analyzed when evaluating the risk of alcoholism. In the Taiwanese Chinese we found that, only among those chromosomes containing the ADH3*1 variant (high Vmax), the proportions of chromosomes with ADH2*1 (low Vmax) and those with ADH2*2 (high Vmax) are significantly different between alcoholics and controls (P<10-5). The proportions of chromosomes with ADH3*1 and those with ADH3*2 are not significantly different between alcoholics and controls, on a constant ADH2 background (with ADH2*1, P=.83; with ADH2*2, P=.53). Thus, the observed differences in the frequency of the functional polymorphism at ADH3, between alcoholics and controls, can be accounted for by the disequilibrium with ADH2 in this population.
CD26, a 110 kDa cell surface glycoprotein, exhibits dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) enzyme activity and plays an important role in T cell co-stimulation. In the present study, the function of CD26/DPPIV in transendothelial migration was examined using beta-chemokines as chemoattractants. When soluble recombinant CD26 (sCD26/DPPIV+) was added to the transendothelial chemotaxis system, chemotactic migration of T cells toward RANTES was significantly enhanced. Addition of sCD26 to 50 ng/ml of RANTES enhanced the migratory response by a factor of two compared to RANTES alone, whereas mutant soluble CD26 (mCD26), lacking the DPPIV enzyme activity, had no enhancing effect on RANTES-induced T cell migration. In the process of analyzing the mechanisms of the enhancement of T cell migration by sCD26, we showed that RANTES was cleaved by sCD26 under physiologic conditions at the precise site characteristic of its enzyme specificity. However, synthesized RANTES which lacks two N-terminal amino acids showed a chemotactic activity equivalent to full-length RANTES on T cells. Furthermore, addition of sCD26 showed enhancement of T cell migration induced by both forms of RANTES. In contrast to T cells, the truncated RANTES is inactive in chemotaxis of purified monocytes and supplement of sCD26 but not mCD26 reduced the migratory response of monocytes to RANTES. These results suggest that CD26/DPPIV differentially regulate the chemotactic response of T cells and monocytes to RANTES.
BACKGROUND: Recent studies on the genetics of alcoholism have examined the association between alcoholism and the dopamine D2 receptor locus (DRD2); our study of Chinese Han gave negative results (Lu et al., 1996). The different genotypes at the genes encoding the enzymes involved in alcohol metabolism, class one alcohol dehydrogenase (ADH2 and ADH3) and mitochondrial aldehyde dehydrogenase (ALDH2), have previously been shown to confer different predispositions to the development of alcoholism in Chinese Han males (Thomasson et al., 1991; Chen WJ et al., 1996; Chen CC et al., unpublished data). Therefore, association studies of alcoholism in Chinese Han might be more sensitive if controlled for the genotypes of ADH2,ADH3, and ALDH2, when other loci, such as DRD2, are examined. This study employs such controls to evaluate the evidence for an association between alcoholism and TaqI-A and TaqI-B genotypes and haplotypes at DRD2 in the Chinese Han population. METHODS: We studied 213 Chinese Han subjects (128 alcoholics and 85 nonalcoholics) with alcohol dependence defined according to DSM-III-R criteria. RESULTS: Significant linkage disequilibrium was observed between the TaqI-A and TaqI-B sites at the DRD2 locus, as previously seen in smaller samples, but no significant association was observed between these genetic variants at the DRD2 locus and alcoholism in Chinese Han. Several different stratifications by ADH and ALDH2 genotypes were examined; no genotypes or haplotypes at DRD2 differ between alcoholics and nonalcoholics except for a small number of nominally significant p-values which do not constitute significant results given the many tests done, some of which are not independent of one another due to linkage disequilibrium. These tests included considering the high risk (ADH2*1/*1; *1/*2; ADH3*1/*2; *2/*2; and ALDH2*1/*1) and the low risk (ADH2*2/*2; ADH3*1/*1; and ALDH2*1/*2; *2/*2) groups of alcoholics, as well as nonalcoholic controls. CONCLUSIONS: After stratification by the relevant genotypes of ADH2, ADH3, and ALDH2 no significant association exists between the genetic variants at the DRD2 locus and alcoholism in the Chinese Han population.
A series of gamma-aminobutyric acid (GABA) 1 analogs was prepared in which the carboxylic acid group of GABA was replaced with a sulfinic acid group and their affinity for the GABAB receptor investigated.
Previous studies have shown that triggering multiple myeloma (MM) cells via CD40 induces IL-6-mediated autocrine growth as well as increased expression of cell surface adhesion molecules including CD11a, CD11b, CD11c, and CD18. In this study, we generated the 5E2 mAb which targets an antigen that is induced upon CD40 ligand (CD40L) activation of MM cells. Immunofluorescence, immunoprecipitation, and protein sequencing studies identified the target antigen of 5E2 mAb as the 86-kD subunit of the Ku autoantigen. We demonstrate that increased cell surface expression of Ku on CD40L-treated cells is due to migration of Ku from the cytoplasm to the cell surface membrane. Moreover, cell surface Ku on CD40L-treated MM cells mediates homotypic adhesion of tumor cells, as well as heterotypic adhesion of tumor cells to bone marrow stromal cells and to human fibronectin; and 5E2 mAb abrogates IL-6 secretion triggered by tumor cell adherence to bone marrow stromal cells. These data suggest that CD40L treatment induces a shift of Ku from the cytoplasm to the cell surface, and are the first to show that Ku functions as an adhesion molecule. They further suggest that cell surface Ku may play a role in both autocrine and paracrine IL-6-mediated MM cell growth and survival.
Synthetic organic polymers used to purify drinking water are severely limited in that their impurities and by-products harm human health. In this study, the undesired effects resulted from chlorination and the enhanced attenuation of toxic organic compounds in drinking water from using synthetic organic polymer coagulants were investigated. In the simulated drinking water purification processes, synthetic organic polymers were used as coagulant aids, reacted with a disinfectant(chlorine) and formed a large number of volatile organic compounds (VOCs). Chloroform and benzene which, are carcinogenic compounds, had the maximum formation potential. Experimental results indicated that the total formation potential of these disinfection by-products significantly increased in the presence of turbidity. On the other hand, adding organic polymers to the coagulation systems resulted in more extensive remove of toxic organic compounds and turbidity. In coagulation and flocculation processes, the formation of clay/polymer complexes can facilitate the removal of toxic organic compounds in contaminated water.
The clinical and radiographic results of 86 primary total hip arthroplasties performed in 74 patients from 1983 to 1987 with a cemented metal-backed acetabular component and a cemented collared straight femoral stem with a 32-mm head were reviewed at a mean follow-up of 10.1 years. Seven patients (9.2%) underwent acetabular component revision at a mean of 9.0 years after implantation; an additional 24 components (31.6%) demonstrated evidence of radiographic loosening, resulting in a total failure rate of 40.8%. Periacetabular radiolucencies were noted in Charnley zones at the following rates: 34.2% in zone I, 18.4% in zone II, and 27.6% in zone III. In addition, 18.4% and 38.2% of implants demonstrated evidence of migration and excessive polyethylene wear. Excessively vertical cup placement (>49 degrees inclination) at the time of initial arthroplasty was statistically correlated with polyethylene wear, implant migration, and fixation failure. A trend of increasing implant failure was also noted with decreasing polyethylene liner thickness. Periacetabular cement mantle thickness was not statistically correlated with subsequent component loosening or failure. Results of Kaplan-Meier survivorship analysis using revision as an endpoint showed 93.6% survivorship at 10 years and 88.4% at 12 years. The mean modified Harris hip scores were 46.9 preoperatively and 81.8 at final follow-up. The significant overall rates of radiographic loosening, migration, polyethylene wear, and implant revision confirm the suspected trend of increasing failure rates of cemented metal-backed acetabular components over time.
OBJECTIVES: A defect in mitochondrial energy conservation is strongly suggested to be involved in the pathogenesis of Leber's hereditary optic neuropathy (LHON). The authors therefore compared the energy charge in lymphocytes among patients with LHON, their asymptomatic maternal lineages, and normal control subjects. MATERIALS AND METHODS: Blood samples were obtained from 7 patients, 10 asymptomatic maternal relatives, and 16 normal subjects. Molecular analysis confirmed that all had the homoplasmic 11,778 point mutation in the mtDNA of their blood cells. The concentrations of adenosine triphosphate (ATP), diphosphate (ADP), and monophosphate (AMP) were determined by high-performance liquid chromatography. The energy charge was calculated as (ATP + 1/2 ADP)/(ATP + ADP + AMP). RESULTS: The mean energy charges of lymphocytes were 0.871 +/- 0.049 in patients with LHON, 0.884 +/- 0.061 in their asymptomatic maternal relatives, and 0.885 +/- 0.061 in normal controls, respectively. No statistically significant difference was found among the three groups. CONCLUSIONS: Although the study did not find the anticipated change in energy charge in peripheral blood cells, this neither confirms nor rejects the notion that a defect in the mitochondrial oxidative phosphorylation system is involved in the pathogenesis of LHON.
OBJECTIVE: To investigate the presence of human papillomavirus (HPV) in human sperm cells and to evaluate potential effects of HPV on the sperm functions. DESIGN: A descriptive clinical study. PATIENT(S): Specimens of semen were collected from 24 randomly selected patients who attended the fertility clinics at Chang Gung Memorial Hospital. MAIN OUTCOME MEASURE(S): The presence of HPV DNA and RNA were examined by polymerase chain reaction. Semen quality and sperm cell function were analyzed by computer-aided autoanalyzer. RESULT(S): Human papillomavirus type 16 DNA and RNA were found in 6 (25%) and 2 (8%) of the sperm cells specimens, respectively. Human papillomavirus type 18 DNA and RNA were present in 11 (46%) and 5 (21%) of the same sperm cells specimens, respectively. Incidence of asthenozoospermia among patients infected with either HPV was significantly higher than in those without HPV in their sperm cells (75% versus 8%). Although performance of curvilinear velocity, straight-line velocity, and mean amplitude of lateral head displacement was significantly lower in HPV-infected specimens, the differences of linearity, beat cross frequency, and straightness were not statistically significant. CONCLUSION(S): These results suggest that human papillomavirus can be found in human sperm cells and that certain HPV-specific genes are actively transcribed. Sperm motility parameters seem to be affected by the presence of HPV in the sperm cells, and also the incidence of asthenozoospermia may be associated with HPV infection.