h --> mutau at Hadron colliders

We study the observability for a lepton flavor-changing decay of a Higgs boson h--> mutau at Hadron colliders. Flavor-changing couplings of a Higgs boson exist at tree level in models with multiple Higgs doublets. The hmutau coupling is particularly motivated by the favorable interpretation of nu(mu)-nu(tau) oscillation. We find that at the Tevatron run II the unique mutau signature could serve as the Higgs discovery channel, surpassing expectations for Higgs boson searches in the SM and in a large parameter region of the MSSM. The sensitivity will be greatly improved at the LHC, beyond the coverage at a muon collider Higgs factory.

Reduced cellular transport and activation of fluoropyrimidine nucleosides and resistance in human lymphocytic cell lines selected for arabinosylcytosine resistance

Arabinofuranosylcytosine (araC) resistant H9-araC0.05 and H9-araC0.5 sublines were obtained following in vitro exposure of H9 cells to 0. 05 and 0.5 microM araC, respectively. These cell lines were 83.3- and 266.7-fold, 21- and 80-fold, and 2.4- and 4.0-fold more resistant to 5-fluorouridine (FUR), 5-fluoro-2'-deoxyuridine (FdUR), and 5-fluorouracil (FU), respectively. Compared with H9 cells, the cellular accumulation of FUR was 2.2 and 0.2%, FdUR 15.6 and 0.9%, and FU 56.9 and 66.5% in H9-araC0.05 and H9-araC0.5 cells, respectively. An araC resistant HL60 cell line (promyelocytic cell line) was 5.0- and 1.7-fold resistant to FUR and FdUR, respectively, but displayed no resistance to FU. The lower FUR and FdUR nucleotide levels in the resistant cells were a result of reduced cellular transport and uridine kinase (UR kinase) and thymidine kinase (TK) activities. Compared with the parental cell line, the p-nitrobenzyl thioinosine (an inhibitor of nucleoside transport) binding sites also were lower in the araC resistant cells. There was no difference in the expression of multidrug-resistant protein and thymidylate synthase mRNA in the parental and the resistant cell lines. Data presented here suggest that araC exposure of H9 cells, in addition to araC resistance, induced/selected cells that were resistant to FUR and FdUR. These cells had altered cellular drug transport and lower TK and UR kinase activities. Further studies to understand molecular mechanisms of this phenomenon are warranted.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part IV: Comparisons of dietary intake

STATEMENT OF PROBLEM

It is unclear whether the replacement of conventional mandibular dentures with implant-supported overdentures alters the diet and thus improves the nutritional intake of edentulous persons.

PURPOSE

The purpose of this study was to compare the pretreatment and posttreatment diets of edentulous diabetic patients who received new dentures with either a conventional complete mandibular denture (CD) or a mandibular implant-supported overdenture (IOD).

MATERIAL AND METHODS

New dentures were made for 89 edentulous diabetic patients with acceptable metabolic control without insulin (NIT) or with insulin (IT). A randomized approach was used to assign 37 patients a mandibular CD and 52 patients a mandibular IOD supported by 2 cylindrical implants. Of the 89 patients, 58 submitted a dietary log for 7 consecutive days before treatment (PT) and 6 months after treatment completion (PTC). An average daily intake of 28 essential nutrients was determined for each patient at each time interval. Separate 2 x 2 x 2 repeated analysis of variance (ANOVA) tests were performed for each nutrient to compare the means of the 2 denture groups (CD and IOD), 2 diabetic groups (NIT and IT), and 2 time intervals (PT and PTC). The intakes were also compared with the recommended daily allowance (RDA).

RESULTS

ANOVAs for all 28 nutritional variables showed no main effect for either denture type or diabetic treatment. Time effects were seen for magnesium, potassium, copper, and monounsaturated fats. The PTC mean intake of the total sample (N = 58) decreased for all 3 minerals and increased for monounsaturated fats with study dentures. Post hoc tests showed the differences between PT and PTC means to be statistically significant for only magnesium (P=.043) and potassium (P=.015). The percentage of patients with PT intake 25% or more below the RDA ranged from 33% to 85% in the CD group and from 24% to 100% in the IOD group for the same 11 nutrients. PTC fiber intake deficiency was noted in almost all participants. Carbohydrate consumption was markedly lower than that recommended by the American Diabetic Association.

CONCLUSION

As is often the case with elderly groups, this group of edentulous diabetic patients showed highly comprised nutritional intakes of fiber, vitamins, and minerals. The replacement of old dentures with new dentures that included either a mandibular CD or IOD did not alter patient diets such that the patients improved their nutritional intakes of essential micronutrients and macronutrients.

Prevalence of HTLV-I-associated T-cell lymphoma

In order to assess the prevalence rate of HTLV-1-associated T-cell lymphomas and human retrovirus infection in general, approximately 21,000 individuals representing various patient populations, retroviral risk groups, and blood donors were examined for HTLV-I, HTLV-II, HIV-1, or HIV-2 infection using serologic and PCR assays. The prevalence rates among volunteer blood donors were 0.02% and 0% for HTLV and HIV, respectively. Significantly increased HTLV prevalence rates were observed among paid blood donors, African American health care clinic patients, Amerindians, recipients of HTLV-positive cellular blood products, intravenous drug users, sexual contacts and family members of HTLV-positive people, and patients with primary thrombocytosis and other-than-low-grade non-Hodgkin's lymphoma (NHL). Among some of these groups there were significant differences in the prevalence of HTLV-I versus HTLV-II. The eight HTLV-positive NHL patients all had mature, high-grade, CD4+ T-cell lymphomas with clonally integrated HTLV-I, for a prevalence of 4% among other-than-low-grade NHL patients. Seven of the eight died from their disease within 2 years despite treatment. Interestingly, two groups at risk for HTLV infection, namely needle stick victims and recipients of HTLV-infected and/or pooled plasma products, showed no evidence for infection. Significantly increased HIV-1 prevalence was observed among paid blood donors, African Americans, homosexuals, female prostitutes, hemophiliacs, and other-than-low-grade NHL patients. Only one patient was infected with HIV-2. Of the nine HIV-positive, other-than-low-grade NHL patients, seven HIV-1 positives had B-cell lymphomas, one HIV-1 positive had an HTLV-I-positive CD4+ T-cell lymphoma, and one infected with HIV-2 had a CD4+ T-cell lymphoma that was HTLV negative. The data indicate that HTLV-I lymphoma, while uncommon, is not necessarily rare among other-than-low-grade NHL cases in the United States and, given its poor prognosis, should probably be studied separately in clinical trials.

[CT guided percutaneous fine needle aspiration for early diagnosis of pancreatic infection after acute necrotizing pancreatitis]

OBJECTIVE

To assess CT-guided percutaneous fine needle aspiration (FNA) for early diagnosis of pancreatic infection after acute necrotizing pancreatitis.

METHODS

CT-guided percutaneous FNA was employed to diagnose pancreatic infection after acute necrotizing pancreatitis in 14 patients. The aspirates were smeared, cultured and subjected polymerase to chain reaction (PCR) for detecting bacteria.

RESULTS

Ten patients were diagnosed as having pancreatic infection and 4 non-pancreatic infection. FNA was totally performed for 15 times: left retroperitoneal route for 12 times, left and right retroperitoneal route for one time, and transperitoneal route for two times. The sensitivity of smear, PCR, culture to diagnose pancreatic infection was 7/10, 9/10, 10/10, respectively. Their specificity was 4/4, and the time for obtaining the results was 30 minutes, 4 hours, 3 days respectively.

CONCLUSIONS

Retroperitoneal approach can be used for most patients with acute necrotizing pancreatitis when performing CT guided-percutaneous FNA. PCR of aspirates is a rapid and accurate method to diagnose pancreatic infection.

[Detection of K-ras gene mutations in DNA extracted from the plasma of patients with pancreatic cancer]

OBJECTIVES

To detect mutations of the K-ras codon 12 in DNA extracted from the plasma of patients with pancreatic cancer, and to explore the possibility of using this method in early diagnosis of pancreatic cancer.

METHODS

Plasma DNA was isolated from the blood of 22 patients with pancreatic cancer and from 20 normal controls. K-ras codon 12 mutations were detected by mutant enriched polymerase chain reaction-restriction fragment length polymorphism technique and subsequent product sequencing. The relation of K-ras mutations in plasma to clinical features in pancreatic cancer patients was analyzed.

RESULTS

Seventeen (77.3%) of 22 patients with pancreatic cancer had a codon 12 K-ras mutation in their plasma DNA. In two patients, the PCR products were sequenced and the mutations were confirmed. The occurrence of K-ras mutations in the plasma DNA was not related to tumor location, tumor size, and TNM stage. No K-ras mutation was detected in the plasma specimen of any of the normal controls.

CONCLUSIONS

K-ras mutations are frequently found in the plasma DNA of patients with pancreatic cancer. Analysis of K-ras mutation in the plasma DNA may be useful in the early detection of pancreatic cancer.

Day 3 morphology is a poor predictor of blastocyst quality in extended culture

OBJECTIVE

To determine how the quality of blastocysts formed on day 5/6 of extended culture compares with their morphology on day 3.

DESIGN

Retrospective observational study of IVF laboratory records.

SETTING

Private assisted reproduction clinic.

PATIENT(S)

101 IVF cycles in which 5 to 25 embryos were produced. The average maternal age was 33.1 years.

INTERVENTION(S)

Embryos were individually cultured in vitro in sequential media for an extended time to enable use of blastocysts for fresh transfer or cryopreservation.

MAIN OUTCOME MEASURE(S)

Comparison of embryo quality for putative ET or cryopreservation on day 3 with quality of embryos used for actual ET and cryopreservation on day 5/6.

RESULT(S)

Of 1,263 cleaving embryos, 559 were judged to have been suitable for use on day 3; 355 would have been used for ET (average per ET, 3.5) and 204 would have been frozen (equivalent to 44% utilization). In actuality, 471 blastocysts were used on day 5/6, of which 234 were transferred (average per ET, 2.3), and 237 were frozen (equivalent to 37% utilization). Only 48% embryos that would have been chosen for ET and/or cryopreservation on day 3 were eventually used in such a manner at the blastocyst stage. Historically, the rate of viable pregnancy from day 3 transfers was 30.5% per transfer; this rate increased to 45% with routine day 5/6 transfers.

CONCLUSION(S)

Extended culture of human embryos seems to increase discrimination of potential embryonic viability. Criteria for embryo selection on day 3 seem to be inadequate. Extended in vitro culture may therefore be an effective means of optimizing IVF clinical success.

Dietary olive oil enhances murine lymphocyte calcium uptake

BACKGROUND

Dietary lipids enhance immune function and improve outcome from injury or infection in animal models. We tested the hypothesis that amount, type, or both, of dietary lipid increases intracellular calcium concentration, a surrogate for lymphocyte activation.

METHODS

Mice were fed 2 weeks on semipurified diets with 5% (by weight [w/w]), 10% (w/w), or 20% (w/w) dietary fat consisting of coconut, olive, safflower, or linseed oil. Changes in intracellular calcium concentration after mitogen stimulation of splenic lymphocytes was estimated by using flow cytometry.

RESULTS

Olive oil diets increase intracellular calcium concentration after concanavalin A, lipopolysaccharide, and CD3 stimulation. On the other hand, linseed oil (which is high in omega-3 fatty acids, which have been shown in other studies to enhance immune function) depresses intracellular calcium levels. The amount of dietary fat had no effect on intracellular calcium.

CONCLUSION

Olive oil merits further study in the application of nutritional pharmacology to immunomodulation of the critically injured, because it may enhance lymphocyte function.

The effects of plasma fentanyl concentrations on propofol requirement, emergence from anesthesia, and postoperative analgesia in propofol-nitrous oxide anesthesia

To determine the effects of plasma fentanyl concentrations on intraoperative propofol requirements, emergence from anesthesia, and relief of postoperative pain, we studied 60 ASA physical status I and II patients undergoing spine fusion. The patients were randomly assigned to four study groups according to the expected intraoperative plasma fentanyl concentrations. Group I received an infusion of saline, and Groups II, III, and IV received fentanyl infusions to maintain the blood levels at 1.5, 3.0, and 4.5 ng/mL, respectively. An infusion rate of propofol was adjusted to keep the mean arterial pressure within 15% of the control value. Inspired nitrous oxide concentrations were maintained at 67%. The following were investigated in each group: 1) an average propofol infusion rate, 2) time to spontaneous eye opening and recovery of orientation (name, date, and place), and 3) total dose of fentanyl used for 24 h after admission to the postanesthetic care unit. Average propofol infusion rates were 10.1 +/- 2.5 (mean +/- SD), 7.5 +/- 1.2, 5.7 +/- 1.1, and 4.9 +/- 1.2 mg. kg(-1). h(-1), in Groups I, II, III, and IV, respectively. Groups receiving fentanyl infusion had significantly smaller infusion rates of propofol (P < 0.01) than the group receiving saline. Among the three fentanyl infusion groups, Group II (P < 0.01) had more than Groups III and IV. The time to spontaneous eye opening and the recovery of orientation were directly related to plasma fentanyl concentrations. The plasma fentanyl levels between Groups III and IV were the same. The total amount of IV patient-controlled analgesia fentanyl during postoperative 24 h increased significantly when the order of plasma fentanyl concentrations was reversed, 913.1 +/- 58.4, 553.4 +/- 129, 222.7 +/- 73.4, and 135.1 +/- 69.5 microg in Groups I, II, III, and IV, respectively. These results suggest that the addition of fentanyl infusions had ceiling effects that reduce the intraoperative propofol requirements according to the plasma fentanyl concentrations. The ceiling effect was demonstrated in the recovery of consciousness but not in the fentanyl requirements for postoperative analgesia.

IMPLICATIONS

The addition of fentanyl, a potent opioid, reduced the intraoperative requirement of propofol, an IV anesthetic, in the order of the plasma fentanyl concentrations. The ceiling effects of fentanyl were demonstrated in the reduction of propofol requirements and recovery of consciousness but not in the fentanyl requirements for postoperative analgesia.

Apolipoprotein B-100 gene Xba I polymorphism and cholesterol gallstone disease

The apolipoprotein (apo) B gene Xba I polymorphism is associated with alterations in serum lipids. Disturbances in serum lipids may be a risk factor for cholesterol gallstone disease. However, the relation between the Xba I polymorphism and cholesterol gallstones is unknown. This study was aimed at characterizing the polymorphism of the apo B gene Xba I in patients with gallbladder stones and the association of Xba I polymorphism with serum lipids. Xba I genotypes were measured by PCR-RFLP, and serum lipids assayed in 190 patients with gallbladder stones and 441 control subjects. The frequency of the X+/- genotype (20.63 vs. 7.94%) and X+ allele (10.79 vs. 3.97%) was significantly higher in the patient group than in the control group. Patients with the X+/- genotype had a significantly higher concentration of total cholesterol, low-density lipoprotein (LDL)-cholesterol, and apo B in serum than patients with the X-/- genotype. The X+ allele of the apo B gene is characterized by a higher cholesterol concentration and a higher LDL-cholesterol concentration in serum, and it may be a marker for increased risk of cholesterol gallstone disease.

High-fat diets suppress CD3 and CD25 expression on the surface of murine lymphocytes

To determine the effects of dietary fats on surface antigen expression, we tested the effects of amount and type of dietary fat on murine lymphocytes. Mice were fed diets with 12 en%, 23 en%, or 47 en% fat containing coconut, olive, safflower, or linseed oil. After 2 wk of ad libitum feeding, the mice were killed and splenic lymphocytes were harvested. Lymphocytes were incubated with fluorescent-tagged monoclonal antibodies and assayed for mean and total surface expression using flow cytometry. Our results show that high-fat (47 en%) diets suppress expression of CD3 and CD25 antigens. We also found that linseed-oil diets suppress expression of CD11a but enhance expression of CD25 antigens. Both CD3 and CD25 are critical for lymphocyte activation, and we conclude that immunosuppression associated with high-fat diets may be associated with suppression of these surface antigens.

Comparison of three treatment options for single brain metastasis from lung cancer

Whole brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), and the combination of both treatment methods were used for the management of single brain metastasis from lung cancer. The purpose of this study is to compare these three different treatment options in terms of local response, survival, and quality of life. From June 1995 to July 1998, 70 lung cancer patients with new diagnosed single brain metastasis were treated with either WBRT alone (n = 29), or SRS alone (n = 23), or the combination of both methods (n = 18). Multiple endpoints, including survival, freedom from local progression (FFLP), freedom from new brain metastasis (FFNBM), local control, Karnofsky performance status (KPS), and causes of death, were measured from the date of treatment completion and compared using univariate and multivariate analyses. For patients treated with WBRT-alone, SRS-alone, and SRS+WBRT, the median survivals were 5.7, 9.3, and 10.6 months, the median FFLP were 4.0, 6.9, and 8.6 months, the median FFNBM were 4.1, 6.7, and 8.6 months, and the local response rates were 55.6, 87.0, and 88.9%, respectively. Four of the 29 patients treated with WBRT-alone continued with progression of disease. The post treatment KPS showed improvement in 41.4, 82.6, and 88.9% of patients treated with WBRT-alone, SRS-alone, and SRS+WBRT, respectively. The progression of new and/or recurred metastatic brain tumor as the cause of death accounted for 51.7%, 50. 0%, and 28.3% of the patients treated with WBRT-alone, SRS-alone, and SRS+WBRT, respectively. Univariate analyses showed that the significant differences among the three treatment arms were observed based on all of the above mentioned endpoints. However, the comparison between SRS-alone and SRS+WBRT groups indicated that adding WBRT only improves FFNBM (P = 0.0392). Cox regression analyses revealed no significant difference in both of the KPS (P = 0.1082) and causes of death (P = 0.081) among the three arms. Both SRS alone and SRS+WBRT seem better in prolonging life and improving quality of life than WBRT alone for patients with single brain metastasis from lung cancer. But the combined therapy did not show significant advantage over SRS alone in improving survival, enhancing local control, and quality of life except for a more favorable FFNBM. Further investigation via a randomized trial is needed to access the value of adding WBRT to SRS in the management of this group of patients. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 37-45 (2000).

New applications of photoacoustics to the study of photosynthesis

Photoacoustic methods offer unique capabilities for photosynthesis research. Phenomena that are readily observed by photoacoustics include the storage of energy by electron transport, oxygen evolution by leaf tissue at microsecond time resolution, and the conformational changes of photosystems caused by charge separation. Despite these capabilities, photoacoustic methods have not been widely exploited in photosynthesis research. One factor that has contributed to their slow adoption is uncertainty in the interpretation of photoacoustic signals. Careful experimentation is resolving this uncertainty, however, and technical refinements of photoacoustic methods continue to be made. This review provides an overview of the application of photoacoustics to the study of photosynthesis with an emphasis on the resolution of uncertainties in the interpretation of photoacoustic signals. Recent developments in photoacoustic technology are also presented, including a microphotoacoustic spectrometer, gas permeable photoacoustic cells, the use of photoacoustics to monitor phytoplankton populations, and the use of photoacoustics to study protein dynamics.

Cross-resistance of dideoxycytidine-resistant cell lines to azidothymidine

2',3'-Dideoxycytidine (ddC) and azidothymidine (AZT) inhibit HIV-1 replication and currently are used in AIDS therapy. Long-term use of the drugs is associated with the selection of drug-resistant HIV strains, thus limiting their effectiveness. Another mechanism, associated with their altered metabolism in host cells, also can cause "cellular" drug resistance. Human lymphocytic H9 cell lines (H9-ddC0.5w and H9-ddC5.0w) selected for ddC resistance by exposure to 0.5 and 5.0 microM ddC were found to be cross-resistant to AZT. Compared with controls, the thymidine kinase (TK) activities in H9-ddC0.5w and H9-ddC5.0w cells were 56.7 and 51.4% (with thymidine as a substrate) and 50.3 and 42% (with AZT as a substrate). Consequently the cellular incorporation of AZT and thymidine (24-hr incubation) also was reduced to 51.3 and 70.0% in H9-ddC0.5w cells and to 12.1 and 17.3% in H9-ddC5.0w cells. A 3-hr incubation with 25 microM AZT and ddC decreased their cellular incorporation to 50.5 and 76.15% in H9-ddC0.5w cells and to 12.95 and 47.8% in H9-ddC5.0w cells compared with H9 cells. Thus, the change in AZT accumulation did not correlate exactly with the decrease in TK activity and far exceeded the effect on ddC accumulation. Evidence is presented that ddC, in addition to deoxycytidine kinase, affected TK1 activity. The involvement of multidrug resistance proteins in the mechanism of the resistance was ruled out by the failure of trifluoperazine and verapamil to alter cellular accumulations of AZT, ddC, daunorubicin, and rhodamine-123. Development of cellular ddC and AZT cross-resistance may affect the therapeutic efficacy of these antiviral agents.

Randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part III: comparisons of patient satisfaction

STATEMENT OF PROBLEM

There is insufficient evidence to indicate the functional superiority of mandibular implant-supported overdentures to justify their use in edentulous patients.

PURPOSE

This study compared the benefits perceived by patients who received a new maxillary denture and a mandibular conventional denture (CD) and an implant-supported overdenture (IOD).

METHOD

New maxillary and mandibular dentures were delivered to 89 diabetic denture wearers with clinically acceptable metabolic control who treated their diabetes either with insulin (IT) or without insulin (NIT). Of the 89 patients, 37 received maxillary and mandibular CDs and 52 received a maxillary CD and an IOD. Two questionnaires with categorical responses were used; the first contained 13 questions to ascertain a patient's absolute assessments of original dentures at entry and study dentures at 6- and 24-months after treatment completion; the second questionnaire had 11 questions that assessed the relative change perceived by patients with study dentures. Of the 78 patients who completed the posttreatment (PT) assessments at 6 months, 68 patients provided longitudinal data for questionnaire I and cross-sectional data for questionnaire II. In addition, 46 patients (18 CD and 28 IOD) also provided PT assessments at 24 months.

RESULTS

Both mean scores and percentage distributions of longitudinal data for questionnaire I showed perceptual improvements with both types of study dentures. Improvements were higher in the IOD than in the CD group. Mean scores failed to show any significant differences between the 2 treatment groups. The only significant difference was found in the change in percentage distributions for perceptual chewing ability in favor of the IOD group. Even this advantage was lost at 24 months. With the comparative questionnaire, a higher percentage of patients in the IOD group than in the CD group perceived improvements with study dentures from their original dentures in chewing ability, chewing comfort, and denture security. However, mean differences were statistically significant in favor of the IOD group only for chewing ability and less difficulty to chew hard foods.

CONCLUSION

The mandibular implant-supported overdenture offers same advantage in terms of perceived chewing function over the conventional denture.

Support for the availability of prenatal testing for neurological and psychiatric conditions in the psychiatric community

Faculty and residents of the University of Michigan Department of Psychiatry, members of the Alliance for the Mentally Ill (AMI), and university students were surveyed to elicit attitudes toward the availability of prenatal testing and genetic therapy or enhancement for early- and late-onset psychiatric diseases compared to neurological disorders and human traits. They were asked to complete a written questionnaire designed to assess their opinions as to whether prenatal testing and genetic therapy or enhancement should be applied to 16 selected "disease" phenotypes or human traits: eight early- and late-onset psychiatric conditions, four neurological disorders, and four human traits. Twenty-two percent returned the written survey. The majority of all respondents supported the availability of prenatal testing for well-defined, serious psychiatric or neurological phenotypes and found testing for human traits less desirable. The percentages of respondents supporting availability of testing increased if in utero curative gene therapy was available. Response to the survey differed on the basis of gender and age, as well as personal versus professional familiarity with the condition. The results of this pilot study suggest that a majority of the population, including psychiatrists, will support the public availability of prenatal diagnosis for serious psychiatric or neurological phenotypes, even if no in utero curative therapy is available. Support for testing for human traits was not strongly endorsed.

Collateral resistance of a dideoxycytidine-resistant cell line to 5-fluoro-2'-deoxyuridine

Exposure of a human lymphocytic cell line, H9 cells, to 0.5 microM and 5.0 microM dideoxycytidine (ddC) resulted in isolation of ddC-resistant H9-ddC0.5w and H9-ddC5.0w cell lines. In addition, these cell lines were also resistant to azidothymidine and had reduced deoxycytidine kinase and thymidine kinase activities. We now show that these cell lines are 4-fold and 2000-fold collaterally resistant to 5-fluoro-2'-deoxyuridine (FdUR), respectively, but not to 5-fluorouracil (FU). Biochemical evaluations show that, compared to the parental cells, the FdUR phosphorylation was reduced to 36.3% and 9.2% and the FdUMP levels were decreased to 48.1% and 1.2% in these cell lines. Taken together, the data suggest that ddC, an antiviral agent, is capable of inducing resistance to FdUR-a drug that is not its analog and which has a different metabolism, target site, and mechanism of action.

[Association of polymorphisms of apolipoprotein B gene with cholesterol gallstone disease]

OBJECTIVE

To investigate the association between the apolipoprotein B (apoB) gene polymorphic sites Ins/Del and Xbal, and cholesterol gallstone disease.

METHODS

The two polymorphic sites of apoB gene were examed in 101 cholesterol gallstone patients and 50 controls by polymerase chain reaction and restriction fragment length polymorphism methods.

RESULTS

For Xbal polymorphic site, the frequency of the rare allele X+ and the distribution of X+X- genotype were significantly higher in the patient group than in the control group (P < 0.05). For Ins/Del polymorphic site, no significant difference was found in allele frequency and genotype distribution between the patient group and the control group.

CONCLUSIONS

Xba1 polymorphism of apoB gene may be associated with cholesterol gallstone disease. The association, however, is not present for Ins/De1 polymorphism of apoB gene with cholesterol gallstone disease.

[Correlation between gene expression of CCK-A receptor and gallbladder emptying in gallstone patients]

OBJECTIVE

To investigate the expression of CCK-A receptor and its relation with gallbladder hypomotility in patients with gallstone.

METHODS

20 patients with gallstone and 10 normal subjects were studied and gallbladder emptying function was measured by B ultrasonography. The other 8 patients without gallstone who died of accident were selected as controls for measuring mRNA expression of CCK-A receptor of gallbladder; RT-PCR was used to explore gene expression of CCK-A receptor of gallbladder.

RESULTS

The gallbladder motility was significantly impaired in gallstone patients. The patients had lower mRNA expression of CCK-A receptor than control subjects (0.633 +/- 0.167 vs. 0.944 +/- 0.230, P < 0.01), and so did patients with impaired gallbladder motility then those with normal motility (0.544 +/- 0.124 vs. 0.768 +/- 0.131, P < 0.05). Furthermore, the change of expression of CCK-A receptors was markedly correlated with gallbladder emptying (r = 0.925, P < 0.01).

CONCLUSIONS

mRNA expression of CCK-A receptor in gallstone patients decreases, which was related to gallbladder hypomotility. The down-regulation of gene expression of CCK-A receptor plays an important role in gallbladder hypomotility in patients with gallstone.

[Effects of short veno-venous hemofiltration on severe acute pancreatitis]

OBJECTIVE

To estimate the effects of therapy of short veno-venous hemofiltration (SVVH, 4hr) on severe acute pancreatitis (SAP).

METHODS

Twenty patients were divided randomly into hemofiltration group (HF, 10 pts) and non-hemofiltration group (NHF, 10 pts). The local, systemic manifestations were compared between two groups; and the concentration of serum pro-inflammatory cytokines (TNFalpha, IL-1beta, IL-6, IL-8, sIL-2R) and anti-inflammatory cytokines (IL-2, IL-10) were determined at different observation points.

RESULTS

In the HF and NHF group, the duration for disappearance of abdominal pain and tenderness, and amelioration for abdominal distension was (8.5 +/- 6.3) d vs. (90.0 +/- 49.0) d and (16.9 +/- 5.2) d vs. (63.4 +/- 36.0) d. CT scores at the 14th day and APACHE II scores at the 10th day was (5.6 +/- 1.3) vs. (7.7 +/- 0.8) and (4.5 +/- 1.5) vs. (7.4 +/- 2.1). The average hospital stay and cost of therapy were (33.0 +/- 20.7) d vs. (56.4 +/- 16.0) d and (53,200 +/- 16,000) vs. (89,100 +/- 25,000) RMB (P < 0.05). The concentration of 5 serum pro-inflammatory cytokines at each observation points after hemofiltration was decreased significantly (P < 0.05) in the HF group. But the concentration of the two serum anti-inflammatory cytokines was increased significantly (P < 0.05) as compared with that of the NHF group.

CONCLUSIONS

Through SVVH, the imbalance of pro-inflammatory and anti-inflammatory cytokines has been corrected at early stage; thus, the severity of the disease is ameliorated significantly and the efficacy of therapy is increased.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part II. Comparisons of masticatory performance

STATEMENT OF PROBLEM

Convincing evidence is lacking to demonstrate the functional superiority of mandibular implant-supported overdentures over conventional dentures.

PURPOSE

This randomized clinical trial was conducted to compare masticatory functional effectiveness of mandibular implant-supported overdentures and conventional dentures in diabetic denture wearers with clinically acceptable metabolic control.

METHODS

A total of 102 edentulous diabetic patients, treated with or without insulin, were randomized to receive a new maxillary and either a mandibular conventional denture or an implant-supported overdenture. Treatment was completed in 89 patients, 37 with conventional dentures and 52 with Hader bar-clip attachment overdentures supported by two IMZ implants. Besides data from medical and dental histories, oromaxillofacial examinations, and questionnaires, masticatory tests were performed by patients before and at 6 and 24 months after treatment completion. Although 78 patients (28 in the conventional, 50 in the overdenture group) performed tests at 6 months after treatment, 68 (25 in the conventional, 43 in the overdenture) had performance data for both entry and 6-month posttreatment intervals.

RESULTS

The two treatment groups were highly comparable in terms of general characteristics, quality of original dentures, tissue support, and past denture experience. No significant differences were found between patients treated for diabetes with or without insulin. All four masticatory performance scores with original dentures were higher in the conventional denture group than the overdenture group. The posttreatment performance scores for the two treatment groups became similar because of the higher gains in the overdenture group. Patients with low initial performance scores showed greater posttreatment gains with both conventional dentures and overdentures.

CONCLUSIONS

The implant-supported overdenture showed no significant advantage over the conventional denture for improving the ability to comminute food in this group of diabetic patients with higher than average initial functional levels observed for other groups of denture wearers in previous studies.

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part I: Methodology and clinical outcomes

STATEMENT OF PROBLEM

Scientific evidence is lacking to support the general application of implant-supported mandibular overdentures.

PURPOSE

This randomized clinical trial was undertaken to compare the efficacy of conventional mandibular and implant-supported overdentures in diabetic edentulous patients with clinically acceptable metabolic control.

METHOD

A total of 102 diabetic patients, treated with or without insulin, were randomized to receive a new maxillary denture and either a conventional or an implant-supported removable mandibular overdenture. Treatment was completed for 89 patients, 37 with the conventional and 52 with implant-supported dentures. Detailed examinations, tests, and questionnaires were given before and at 6- and 24-months after treatment completion. Comparisons between the two treatment groups were made for treatment failures based on prespecifed criteria and the type and amount of maintenance care provided.

RESULTS

The insulin and noninsulin treated groups were collapsed because of the lack of significant differences at entry. The conventional denture and implant-supported overdenture groups were similar in terms of general demographics, medical status, quality of their original dentures and denture support, several functional measures, and patient satisfaction. Treatment was judged to be successful in 56.9% of patients with conventional dentures and 72.1% with overdentures. This difference in success rate was not statistically significant (p > 0.05). Patients with treatment failures in both groups required excessive maintenance care. Those with conventional dentures needed frequent denture base adjustments and relines, whereas those with overdentures required frequent clip replacements and repairs. Although significant improvements were seen with both treatment modalities, a higher percentage of patients with implant-supported overdentures than those with conventional dentures reported improvements in chewing comfort and moderate-to-complete overall satisfaction.

[Polymorphism at the LDL receptor gene locus in patients with cholesterol gallstone disease]

OBJECTIVE

To investigate the association between the dinucleotide repeat polymorphism at the 3' end of the LDL receptor gene and cholesterol gallstone disease.

METHODS

Polymorphism of the (dTA)n was amplified by using polymerase chain reaction, and the alleles identification was performed with denaturing polyacrylamide gel electrophoresis and silver stain technique.

RESULTS

Analysis of allele frequencies in 131 unrelated Chinese gallstone patients and 79 controls indicated that the C allele was more frequent in the patients with cholesterol gallstones than that in the controls (0.40 vs 0.27, P < 0.01), and the frequency of the BB genotype of the LDL receptor gene was markedly lower (P < 0.005), while the CC and BC genotypes were significantly higher in the patients with cholesterol gallstones than in the controls respectively (P < 0.05, P < 0.05).

CONCLUSION

The present study suggests that the LDL receptor gene polymorphism may be associated with cholesterol gallstone disease.