Prognostic value of ST segment depression in acute coronary syndromes: insights from PARAGON-A applied to GUSTO-IIb. PARAGON-A and GUSTO IIb Investigators. Platelet IIb/IIIa Antagonism for the Reduction of Acute Global Organization Network

OBJECTIVES

Our objectives were to develop a risk-stratification model addressing the importance of the magnitude and distribution of ST segment depression in predicting long-term outcomes and to validate the model in an analogous patient population.

BACKGROUND

Although patients without ST segment elevation presenting with acute coronary syndromes represent an increasingly frequent population admitted to coronary care units, little attention has been paid to quantifying their ST segment abnormalities.

METHODS

ST segment depression was categorized into three groups: 1) no ST segment depression; 2) 1-mm ST segment depression in two contiguous leads; and 3) ST segment depression > or =2 mm in two contiguous leads. A logistic regression model was developed using Platelet IIb/IIIa Antagonism for the Reduction of Acute coronary syndrome events in a Global Organization Network (PARAGON-A) data to assess the prognostic value of the extent and distribution of ST segment depression in predicting one-year mortality. The model was validated using the non-ST segment elevation population in Global Use of Strategies To Open occluded arteries in acute coronary syndromes (GUSTO-IIb).

RESULTS

ST segment depression was the strongest predictor of one-year mortality, accounting for 35% of the model's predictive power. Patients with ST segment depression > or =2 mm were approximately 6 times (odds ratio [OR] 5.73, 95% confidence interval [CI] 2.8 to 11.6) more likely to die within one year than patients with no ST segment depression. On validation, the model showed good discriminatory power (c-index = 0.75). Patients with ST segment depression > or =2 mm in more than one region were almost 10 times more likely to die within one year than patients with no ST segment depression.

CONCLUSIONS

These data provide new evidence supporting the powerful prognostic value of the baseline electrocardiogram and, in particular, the magnitude and distribution of ST segment depression in predicting unfavorable events.

Prognostic value of nm23 expression in stage IB1 cervical carcinoma

BACKGROUND

The purpose of this retrospective study was to evaluate the patterns of nm23 expression in stage IB1 squamous cell carcinoma of the uterine cervix, to compare nm23 expression with clinicopathological findings and to assess its prognostic value.

METHODS

Twenty-seven patients with stage IB1 squamous cell carcinoma of the uterine cervix underwent abdominal radical hysterectomy and pelvic lymph node dissection. Expression of nm23 was studied immunohistochemically, followed by amplification and direct sequencing of exons 4 and 5 of the nm23 gene.

RESULTS

Overexpression of nm23 was detected in 18.5% of the tumors and low expression was seen in 33.3%, while negative expression was found in 48.1% of the tumors. Deep cervical stromal invasion (> or =1/2) was found to be associated with the increased risk of lymph node metastases (odds ratio = 17.5). A significantly lower percentage of patients survived when nm23 overexpression was observed (p = 0.0063). Univariate analysis revealed that tumor size (2-3.9 cm), lymph node metastasis, tumor invasion into parametria, tumor invasion into blood/lymph vessel, squamous cell carcinoma (> or =2 ng/ml) and nm23 overexpression had a significantly lower recurrence-free survival rate of the patients. None of the above factors was significant according to multivariate analysis. There were no mutations in exons 4 and 5 of the nm23 gene in stage IB1 squamous cell carcinoma of the uterine cervix.

CONCLUSIONS

This study suggests that expression of nm23 may be indicative of an unfavorable prognosis in patients with stage IB1 squamous cell carcinoma of the uterine cervix.

Chemoprevention of colorectal cancer

Chemopreventive strategies hold substantial promise for reducing the incidence of colorectal cancer, the second leading cause of cancer-related mortality in the United States. This review focuses on recent advances in the identification of molecular targets and novel strategies for chemopreventive intervention. Many clinical trials are now in progress to assess the ability of synthetic agents or nutritional supplements to alter either the number of colorectal adenomas or biomarkers associated with colorectal tumorigenesis. Populations under study include genetically defined high-risk people and those with increased risk based on a personal history of colorectal neoplasia. A recent study showing that celecoxib, a cyclooxygenase-2 inhibitor, can alter the natural history of polyp formation in patients with familial adenomatous polyposis has provided a benchmark for the clinical development of other chemopreventive agents and heightened awareness that colorectal cancer is a preventable disease.

Oxidative stress and liver toxicity in rats and human hepatoma cell line induced by pentachlorophenol and its major metabolite tetrachlorohydroquinone

Pentachlorophenol (PCP) is a pesticide used worldwide in industrial and domestic applications. It is used extensively as biocide and wood preservatives. Metabolic studies carried out in rodents and human liver homogenates have indicated that PCP undergoes oxidative dechlorination to form tetrachlorohydroquinone (TCHQ). Free radical catalyzed tissue injury is thought to play a fundamental role in human disease. In the present study, we examined the effects of PCP and TCHQ on the induction of lipid peroxidation and liver injury in rats. In addition, the cytotoxic dose, cell death mechanisms and related gene expressions induced by PCP and TCHQ were also determined for human hepatoma cell line (Hep G2). The results indicated that more toxic effects could be observed both in rats and human hepatoma cell line treated with TCHQ than its parent compound, PCP. Oxygen species may be involved in the mechanism of TCHQ intoxication since the urinary 8-epi-PGF2alpha and AST, ALT activities can be induced by TCHQ and attenuated by vitamin E treatment. Apoptosis features were found in cells treated with TCHQ but not PCP. TCHQ-induced cell damage may issue signals for the induction of HSPs, the decrease of the bcl/bax protein ratio and the decrease of CAS gene, whereas the PCP-induced damage may not.

Inhibition of human plasmin activity using humic acids with arsenic

In this study, we examined the effects of natural humic acid (HA) purified from drinking well-water in Blackfoot disease (BFD) endemic areas, using synthetic humic acid (SHA), such as protocatechuic acid, ferulic acid, vanillic acid or catechol, and trivalent arsenic on human plasmin activity. Data in this report indicated that both HA and SHA inhibited human plasmin activity by 20-80 and 5-95%, respectively, at concentrations of 20-480 microg/ml. Organometallic complexes composed of HA and arsenic show enhanced inhibition of plasmin activity as compared with either HA or arsenic alone. Monomers of HA or arsenic alone do not inhibit plasma activity. Oxidative stress may play a role in the inhibition of plasma activity, as various free-radical scavengers, such as ascorbic acid, alpha-tocopherol, catalase and superoxide dismutase (SOD), abrogate the inhibitory effects of HA and HA-arsenic complexes. The notion that HA/organometallic complexes (HA/OR) impaired plasmin activity was significant, due to the fact that both of these agents (HA and arsenic) are etiological factors in the development of peripheral vascular diseases, such as BFD. This report substantiates the inhibitory effects of HA/OR on plasmin activity, and thus provides evidence for the partial mechanism of action of HA/OR in BFD.

Gaseous nitric oxide-induced 8-nitroguanine formation in human lung fibroblast cells and cell-free DNA

A time- and dose-dependent increase in 8-nitroguanine (8-NO(2)-G) was observed in human lung fibroblast cells (MRC-5) after treatment with gaseous NO-saturated buffer. It was also found that treatment with the inhibitor of inducible nitric oxide synthase (iNOS), N(G)-nitro-l-arginine methyl ester, significantly reduced the 8-NO(2)-G level in the gaseous NO-saturated buffer-treated MRC-5 cells. These results provide evidence indicating that NO gas causes DNA damage in mammalian cells, which involves the activation of iNOS and the subsequent generation of endogenous NO. On the other hand, a time- and dose-dependent increase in 8-NO(2)-G was also observed while DNA (isolated from MRC-5 cells) was incubated with gaseous NO-saturated buffer. These results suggest that part of the 8-NO(2)-G formation was due to direct modification of gaseous NO on DNA. Furthermore, an increase in nitrite concentration was found in both cell-free and MRC-5 cell-conditioned medium treated with gaseous NO-saturated buffer. Collectively, gaseous NO induced DNA damage by forming 8-NO(2)-G, a modification performed directly by the treated gaseous NO and indirectly by the following induction of endogenous NO. This effect might be an important pathway in genotoxicity of nitric oxides, and 8-NO(2)-G could act as a specific marker for DNA damage induced by gaseous NO, a common contaminatant in air pollution and cigarette smoke.

Centrality dependence of charged particle multiplicity in Au-Au collisions at square root of (s)NN = 130 GeV

We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at square root of [s(NN)] = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta(vertical line eta = 0) = 622+/-1(stat)+/-41(syst). The results, analyzed as a function of centrality, show a steady rise of the particle density per participating nucleon with centrality.

Effect of methylglyoxal on mouse embryogenesis

BACKGROUND

Methylglyoxal (MG), a highly active and mutagenetic compound, has been found widely in a variety of foods and beverages. We investigated the effect of MG on mouse embryo development in-vitro.

METHODS

Two-cell mouse embryos were divided into six groups according to the MG concentration in the culture medium: Group 1 (control group). 0 mM; Group 2, 10(-4) mM; Group 3, 10(-3) mM; Group 4, 10(-2) mM; Group 5, 10(-1) mM; Group 6, 1 mM. Embryo development and cleavage were compared every day for 5 days.

RESULTS

The percentages of embryos reaching blastocyst/hatching stages were as follows: Group 1, 66.8%/34.2%; Group 2, 67.9%/38.7%; Group 3, 56.2%/31.5%; Group 4, 39.4%/14.1%; Group 5, 11.4%/10.2%; Group 6, 0%/0%. Higher MG concentrations (> or = 10(-2) mM) were associated with morphological aberrations and blocked development of embryos.

CONCLUSION

The cutoff value of MG concentration on the mouse embryo development in-vitro is 10(-2) mM. An increased risk of embryotoxicity occurs with MG concentrations > or = 10(-2) mM in vitro. There were no significant effects on the growth rate at MG concentrations of 10(-3) and 10(-4) mM.

Baryon rapidity loss in relativistic Au + Au collisions

An excitation function of proton rapidity distributions for different centralities is reported from AGS Experiment E917 for Au+Au collisions at 6, 8, and 10.8 GeV/nucleon. The rapidity distributions from peripheral collisions have a valley at midrapidity which smoothly change to distributions that display a broad peak at midrapidity for central collisions. The mean rapidity loss increases with increasing beam energy, whereas the fraction of protons consistent with isotropic emission from a stationary source at midrapidity decreases with increasing beam energy. The data suggest that the stopping is substantially less than complete at these energies.

Increased expression of iNOS and c-fos via regulation of protein tyrosine phosphorylation and MEK1/ERK2 proteins in terminal bronchiole lesions in the lungs of rats exposed to cigarette smoke

Epidemiological evidence suggests that smoking is a major cause of human lung cancer. However, the mechanism by which cigarette smoke induces the cancer remains unestablished. To evaluate the effects of cigarette smoke on the expression of inducible nitric oxide synthase (iNOS), nuclear protooncogenes and related mitogen-activated protein kinases (MAPKs) in rat lung tissue, a histopathological study of the effects of gas-phase cigarette smoke on rat lung tissue were carried out. The terminal bronchioles were found to be infiltrated predominantly by lymphocytes in the peribronchiolar region and a mild to moderate degree of emphysema was noted in the alveolar spaces. The terminal bronchioles also showed marked lipid peroxidation, dilatation, and peribronchiolar fibrosis. Immunohistochemical evaluation showed that the expression of iNOS, NF-kappa B, MAPKs (MEK1, ERK2), phosphotyrosine protein and c-fos was increased in the terminal bronchioles but protein kinase C (PKC), MEKK-1, c-jun, p38 and c-myc showed no change. These results provide evidence to suggest that exposure to cigarette smoke results in oxidant stress which leads to the stimulation of iNOS and c-fos together with the induction of protein tyrosine phosphorylation and MEK1/ERK2 which in turn may promote lung pathogenesis.

Nonlinear behavior of trabecular bone at small strains

Study of the behavior of trabecular bone at strains below 0.40 percent is of clinical and biomechanical importance. The goal of this work was to characterize, with respect to anatomic site, loading mode, and apparent density, the subtle concave downward stress-strain nonlinearity, that has been observed recently for trabecular bone at these strains. Using protocols designed to minimize end-artifacts, 155 cylindrical cores from human vertebrae, proximal tibiae, proximal femora, and bovine proximal tibiae were mechanically tested to yield at 0.50 percent strain per second in tension or compression. The nonlinearity was quantified by the reduction in tangent modulus at 0.20 percent and 0.40 percent strain as compared to the initial modulus. For the pooled data, the mean +/- SD percentage reduction in tangent modulus at 0.20 percent strain was 9.07+/- 3.24 percent in compression and 13.8 +/- 4.79 percent in tension. At 0.40 percent strain, these values were 23.5 +/- 5.71 and 35.7+/- 7.10 percent, respectively. The magnitude of the nonlineari't depended on both anatomic site (p < 0.001) and loading mode (p < 0.001), and in tension was positively correlated with density. Calculated values of elastic modulus and yield properties depended on the strain range chosen to define modulus via a linear curve fit (p < 0.005). Mean percent differences in 0.20 percent offset yield strains were as large as 10.65 percent for some human sites. These results establish that trabecular bone exhibits nonlinearity at low strains, and that this behavior can confound intersite comparisons of mechanical properties. A nonlinear characterization of the small strain behavior of trabecular bone was introduced to characterize the initial stress-strain behavior more thoroughly.

Secretory origin and temporal appearance of the porcine beta-microseminoprotein (sperm motility inhibitor) in the boar reproductive system

A specific antiserum against the porcine sperm motility inhibitor (SMI) was used in Western blotting analysis of tissue homogenates to reveal the possible origin of SMI in the boar reproductive system at different ages. The ages of the boar used were day 0, day 15, day 30, day 60, day 100, day 120, day 135, day 150, and day 210. The tissue homogenates of the day 60 and older showed immunoreaction. The results were further checked by indirect immunohistochemical staining and observed under light microscope. The SMI antigen appeared in the epithelial cells and in the lumen of the secretory ducts of the prostate gland. These results indicate that porcine SMI is synthesized only by the postnatal prostate gland. The homogenate of the prostate gland of day 100 was also used for the purification of SMI. The prostatic SMI was co-eluted with the seminal SMI in the reversed phase HPLC. Mass spectrometric analysis of the prostatic SMI revealed a molecular weight of 10,066. These results indicate that the prostatic SMI is identical to that purified from seminal plasma (Jeng et al., 1993; Biochem Biophys Res Communi 191:435-440).

Lewis (FUT3) genotypes in Taiwanese, Thai, and Filipino populations

The Lewis (Le) blood type comprises two major antigens, Le(a) and Le(b), which are encoded by alpha (1,2)-fucosyltransferase (FUT2) and a (1,3/1,4)-fucosyl-transferase (FUT3). In this study, we analyzed the mutations of FUT3 in Taiwanese, Thai, and Filipino populations and correlated these with serologic phenotypes. One hundred and thirty-seven Taiwanese, 71 Thai, and 125 Filipino were studied unselectively. The frequency of the normal and four other mutant alleles for Taiwanese, Thai, and Filipino, respectively, were as follows: 187/274 (68.2%), 87/142 (61.3%), and 160/250 (64.0%) were wild type (Le); 14/274 (5.1%), 1/142 (0.7%), and 1/250 (0.4%) were a T202C/C314T mutation (le202,314); 35/274 (12.8%), 15/142 (10.6%), and 22/250 (8.8%) had the G508A mutation (le508); and 38/274 (13.9%), 39/142 (27.4%), and 67/250 (26.8%) carried the T1067A mutation (le1067). The le445 and le1007 were not detected in this study. Our result provided the first genetic data of the FUT3 gene in these three populations, and the frequency distribution of mutant alleles among Taiwanese, Thai, and Filipinos demonstrates a significant difference (P<0.001). In our study, the le202,314 mutation had considerable frequency in the Taiwanese, but the le1067 mutation had a higher frequency in Thai and Filipinos.

Temporal evolution in the management of acute ST elevation myocardial infarction: the seven-year GUSTO experience from canada and the united states. The North American GUSTO-I and GUSTO-III investigators

BACKGROUND

Temporal changes in baseline characteristics, treatment and clinical outcomes of patients presenting with acute ST elevation myocardial infarction in Canada and the United States have not been examined comprehensively over time.

OBJECTIVES

To evaluate baseline characteristics, process of care and clinical outcomes. Also, to explore whether earlier process-of-care differences between Canada and the United States had changed and, if so, whether they influenced clinical outcomes.

PATIENTS AND METHODS

A total of 13, 888 American and 3011 Canadian patients enrolled in 184 American and 38 Canadian hospitals that participated in both the Global Utilization of Streptokinase and Tissue Plasminogen Activator (alteplase) for Occluded Coronary Arteries (GUSTO-I) trial (1990 to 1993) and the Global Utilization of Strategies to Open Occluded Coronary Arteries (GUSTO-III) trial (1995 to 1997) were studied. Logistic regression was used to identify significant prognostic factors, to assess illness severity at hospital presentation and to classify trends between Canada and the United States.

RESULTS

In both countries, illness severity on admission increased, door-to-needle time for thrombolysis was reduced, intensive care unit stay was shortened and hospital stay decreased from GUSTO-I to GUSTO-III. Whereas the administration of oral nitrates, calcium blockers and beta-blockers at discharge converged over time between countries, the disparity in the use of angiography and revascularization widened; the rise in American revascularization rate was most evident in patients without in-hospital ischemia. The 30-day and one-year mortality rates were comparable and declined nonsignificantly in both countries.

CONCLUSIONS

Despite increased illness severity and varying medication and procedure rates, there was no increase over time in 30-day or one-year mortality; this remained comparable between countries throughout the seven-year observation period.

Canadian-American differences in the management of acute coronary syndromes in the GUSTO IIb trial: one-year follow-up of patients without ST-segment elevation. Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) II Investigators

BACKGROUND

Little information exists concerning practice patterns between Canada and the United States in the management of myocardial infarction (MI) patients without ST-segment elevation and unstable angina.

METHODS AND RESULTS

We examined the practice patterns and 1-year outcomes of 2250 US and 922 Canadian patients without ST-elevation acute coronary syndromes in the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) IIb trial. The US hospitals more commonly had on-site facilities for angiography and revascularization. These procedures were performed more often and sooner in the United States than Canada, whereas Canadian patients were more likely to undergo noninvasive stress testing. The length of initial hospital stay was 1 day longer for Canadian than US patients. Recurrent and refractory ischemia was more common in Canada. One-year mortality was comparable between the 2 countries. However, at 6 months, even after baseline differences were accounted for, the (re)MI rate was significantly higher in Canadian than US patients with unstable angina (8.8% versus 5.8%, P:=0.039), as was the composite rate of death or (re)MI (13.1% versus 9.1%, P:=0.016).

CONCLUSIONS

One-year mortality was comparable between Canada and the United States in both MI and unstable angina cohorts despite higher intervention rates in the United States. However, outcomes at 6 months among patients with unstable angina differed. Whereas more frequent coronary interventions were not associated with reduced recurrent MI or death among MI patients without ST elevation, they may favorably affect outcomes in patients with unstable angina.

Functional interaction between c-Jun and promoter factor Sp1 in epidermal growth factor-induced gene expression of human 12(S)-lipoxygenase

The functional role of the interaction between c-Jun and simian virus 40 promoter factor 1 (Sp1) in epidermal growth factor (EGF)-induced expression of 12(S)-lipoxygenase gene in human epidermoid carcinoma A431 cells was studied. Coimmunoprecipitation experiments indicated that EGF stimulated interaction between c-Jun and Sp1 in a time-dependent manner. Overexpression of Ha-ras and c-Jun also enhanced the amount of c-Jun binding to Sp1. In addition, the c-Jun dominant negative mutant TAM-67 not only inhibited the coimmunoprecipitated c-Jun binding to Sp1 in a dose-dependent manner in cells overexpressing c-Jun but also reduced promoter activity of the 12(S)-lipoxygenase gene induced by c-Jun overexpression. Treatment of cells with EGF increased the interaction between the Sp1 oligonucleotide and nuclear c-Jun/Sp1 in a time-dependent manner. Furthermore, EGF activated the chimeric promoter consisting of 10 tandem GAL4-binding sites, which replaced the three Sp1-binding sites in the 12(S)lipoxygenase promoter only when coexpressed with GAL4-c-Jun () fusion proteins. These results indicate that the direct interaction between c-Jun and Sp1 induced by EGF cooperatively activated expression of the 12(S)-lipoxygenase gene, and that Sp1 may serve at least in part as a carrier bringing c-Jun to the promoter, thus transactivating the transcriptional activity of 12(S)-lipoxygenase gene.

Morphodensitometric analysis of protein kinase C beta(II) expression in rat colon: modulation by diet and relation to in situ cell proliferation and apoptosis

We have recently demonstrated that overexpression of PKC beta(II) renders transgenic mice more susceptible to carcinogen-induced colonic hyperproliferation and aberrant crypt foci formation. In order to further investigate the ability of PKC beta(II) to modulate colonocyte cytokinetics, we determined the localization of PKC beta(II) with respect to cell proliferation and apoptosis along the entire colonic crypt axis following carcinogen and diet manipulation. Rats were provided diets containing either corn oil [containing n-6 polyunsaturated fatty acids (PUFA)] or fish oil (containing n-3 PUFA), cellulose (non-fermentable fiber) or pectin (fermentable fiber) and injected with azoxymethane (AOM) or saline. After 16 weeks, an intermediate time point when no macroscopic tumors are detected, colonic sections were utilized for immunohistochemical image analysis and immunoblotting. Cell proliferation was measured by incorporation of bromodeoxyuridine into DNA and apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling. In the distal colon, PKC beta(II) staining was localized to the upper portion of the crypt. In comparison, proximal crypts had more (P < 0.05) staining in the lower tertile. AOM enhanced (P < 0.05) PKC beta(II) expression in all regions of the distal colonic crypt (upper, middle and lower tertiles). There was also an interaction (P < 0.05) between dietary fat and fiber on PKC beta(II) expression (corn/pectin > fish/cellulose, fish/pectin > corn/cellulose) in all regions of the distal colonic crypt. With respect to colonic cell kinetics, proliferation paralleled the increase in PKC beta(II) expression in carcinogen-treated animals. In contrast, apoptosis at the lumenal surface was inversely proportional to PKC beta(II) expression in the upper tertile. These results suggest that an elevation in PKC beta(II) expression along the crypt axis in the distal colon is linked to enhancement of cell proliferation and suppression of apoptosis, predictive intermediate biomarkers of tumor development. Therefore, select dietary factors may confer protection against colon carcinogenesis in part by blocking carcinogen-induced PKC beta(II) expression.

Prognostic value of p53 expression in stage IB1 cervical carcinoma

The purpose of this retrospective study was to evaluate the patterns of p53 expression in stage IB1 squamous cell carcinoma of the uterine cervix, to compare p53 expression with clinicopathological findings, and to assess its prognostic value. 27 patients with stage IB1 squamous cell carcinoma of the uterine cervix underwent abdominal radical hysterectomy and pelvic lymph node dissection. Expression of p53 was studied immunohistochemically. Overexpression of p53 was detected in 33.3% of the tumors, low expression was seen in 11.1%, and negative expression was found in 55.6%. Deep cervical stromal invasion (> or = 1/2) was found to be associated with the increased risk of lymph node metastases (odds ratio = 17.5). A significantly lower percentage of patients survived when p53 overexpression was observed (p = 0.0315). Univariate analysis revealed that tumor size (2-3.9 cm), lymph node metastasis, tumor invasion into parametria, tumor invasion into blood/lymph vessels, squamous cell carcinoma antigen (> or = 2 ng/ml), and p53 overexpression had a significantly lower recurrence-free survival rate. None of these above factors obtained significance in the multivariate analysis. This study suggests that expression of p53 may be indicative of an unfavorable prognosis in patients with stage IB1 squamous cell carcinoma of the uterine cervix.

Gender prevalence in twin-twin transfusion syndrome

BACKGROUND

This study aimed to determine the gender prevalence of fetuses complicated with twin-twin transfusion syndrome (TTTS).

METHODS

All cases of TTTS corresponded with the following major criteria: a single placenta, monochorion, the same gender, and a combination of polyhydramnios-oligohydramnios. At least one of three minor criteria were required for the establishment of TTTS, including a stuck twin, a birth weight discordance exceeding 20%, and hemoglobin difference > 5 g/dl.

RESULTS

Fifty-six twin pregnancies met the above criteria, of which 33 (58.9%) twin pairs were female. The female tendency existed, but there was a non-significant difference. Mean gestational age at diagnosis was 20.2 +/- 3.2 weeks. The birth weight discordance exceeding 20% was present in 50 of 56 (89.3%), and mean growth discordance was 32% +/- 8%. A stuck twin was noted in 37 of 56 cases (66.1%). The mortality of fetuses or neonates was 34.8% (39/112), including 8 (7.1%) fetal deaths and 31 (27.6%) neonatal deaths. There were no differences in maternal age, parity, or gestational age of delivery between male and female pregnancies.

CONCLUSION

Although the female preponderance did not reach statistical significance, the female tendency might still exist after a larger series analysis. The female tendency may be the result of the gender difference in monochorionic twins. The gender difference could provide research implications and a diagnostic warning for clinicians in monochorionic twin pregnancies before the presence of TTTS.

Tumor promotion of N-nitroso-N-(3-keto-1, 2-butanediol)-3'-nitrotyramine derived from nitrosation of Maillard reaction product in CD-1 mice

N-Nitroso-N-(3-keto-1,2-butanediol)-3'-nitrotyramine (NO-NTA) is a product of a model browning system generated in the presence of sodium nitrite. Our previous study showed that NO-NTA had genotoxicity and proved to be an initiator and promoter on mouse C3H10T1/2 cells. In this study, a two-stage skin carcinogenesis protocol was used to promote CD-1 mouse skin carcinogenesis using NO-NTA. Twice weekly, for 38 weeks, topical application of NO-NTA at the concentration of 250 nmol to mice previously initiated with benzo(a)pyrene (BaP) caused 90% tumor incidence. However, no tumors were observed in mice treated with BaP or treated with NO-NTA alone. The NO-NTA-promoted tumors that were observed histologically in mice showed well-differentiated squamous cell carcinoma with invasion into the subcutaneous region. Application of the same amount of NO-NTA not only caused significant induction of hyperplasia but also epidermal ornithine decarboxylase (ODC) activity. Treatment of mouse skin (1 cm(2)) with various amounts of NO-NTA (10, 50, or 250 nmol) caused production of hydrogen peroxide by 1.63-, 1.91-, and 2. 38-fold, respectively, and marked induction of myeloperoxidase (MPO) by 21-, 39-, and 61-fold. These results indicate that NO-NTA is a new tumor promoter and may induce tumor promotion by oxidant stress in CD-1 mouse skin.

Mouse type-2 retinaldehyde dehydrogenase (RALDH2): genomic organization, tissue-dependent expression, chromosome assignment and comparison to other types

Retinaldehyde dehydrogenase (RALDH) isozymes catalyze the formation of an essential developmental modulator, retinoic acid. We determined the structural organization of mouse type-2 Raldh2 by isolation of overlapping genomic DNA clones from a phage library. The gene consists of 14 exons spanning more than 70 kb of genomic DNA. It was localized to mouse chromosome 6. Northern blot analysis revealed testis-specific expression. The RALDH genes belong to the aldehyde dehydrogenase (ALDH) multi-gene family. Three types of RALDH genes (e.g. human ALDH1/mouse Ahd2/rat RalDH(I), human ALDH11/mouse Raldh2/rat RalDH(II) and human ALDH6) are highly conserved during evolution, sharing about 70% identity at the amino acid level between any two gene types and 90% identity between any two mammalian genes of the same type. Different RALDH types show specific tissue and developmental expression patterns, suggesting (i) a regulatory mechanism of retinoic acid synthesis via different promoters of RALDH genes, and (ii) distinctive biological roles of different isozymes in embryogenesis and organogenesis.

Predictors of outcome in patients with acute coronary syndromes without persistent ST-segment elevation. Results from an international trial of 9461 patients. The PURSUIT Investigators

BACKGROUND

Appropriate treatment policies should include an accurate estimate of a patient's baseline risk. Risk modeling to date has been underutilized in patients with acute coronary syndromes without persistent ST-segment elevation.

METHODS AND RESULTS

We analyzed the relation between baseline characteristics and the 30-day incidence of death and the composite of death or myocardial (re)infarction in 9461 patients with acute coronary syndromes without persistent ST-segment elevation enrolled in the PURSUIT trial [Platelet glycoprotein IIb/IIIa in Unstable angina: Receptor Suppression Using Integrilin (eptifibatide) Therapy]. Variables examined included demographics, history, hemodynamic condition, and symptom duration. Risk models were created with multivariable logistic regression and validated by bootstrapping techniques. There was a 3.6% mortality rate and 11.4% infarction rate by 30 days. More than 20 significant predictors for mortality and for the composite end point were identified. The most important baseline determinants of death were age (adjusted chi(2)=95), heart rate (chi(2)=32), systolic blood pressure (chi(2)=20), ST-segment depression (chi(2)=20), signs of heart failure (chi(2)=18), and cardiac enzymes (chi(2)=15). Determinants of mortality were generally also predictive of death or myocardial (re)infarction. Differences were observed, however, in the relative prognostic importance of predictive variables for mortality alone or the composite end point; for example, sex was a more important determinant of the composite end point (chi(2)=21) than of death alone (chi(2)=10). The accuracy of the prediction of the composite end point was less than that of mortality (C-index 0.67 versus 0.81).

CONCLUSIONS

The occurrence of adverse events after presentation with acute coronary syndromes is affected by multiple factors. These factors should be considered in the clinical decision-making process.

Focus on function in geriatric assessment and rehab

In 1994, the province of Alberta, driven by the need for deficit reduction, began a major restructuring of the provincial health care system. An integral component of this new health structure was accountability for service delivery, including the use of outcome measures to determine service effectiveness. This paper describes the efforts of one program to evaluate the effectiveness of its service delivery, in terms of functional patient outcomes, in the midst of restructuring and budget constraints.

Regulation of cyclooxygenase and 12-lipoxygenase catalysis by phospholipid hydroperoxide glutathione peroxidase in A431 cells

Regulation of arachidonate metabolism in human epidermoid carcinoma A431 cells by phospholipid hydroperoxide glutathione peroxidase (PHGPx) and cytosolic glutathione peroxidase (GPx1) was studied. In order to study the effect of reduced glutathione (GSH) on the catalysis regulation of these oxygenation enzymes, diethyl maleate was used to deplete the intracellular GSH. In the presence of 13-hydroperoxyoctadecadienoic acid, the enzymatic catalysis of cyclooxygenase and 12-lipoxygenase was significantly increased in the GSH-depleted cells. In terms of the inhibitory effect on 12-lipoxygenase, PHGPx was more sensitive to GSH concentrations than GPx1. Inhibition of PHGPx activity by the treatment of cells with antisense oligonucleotide of PHGPx mRNA increased the enzymatic catalysis of both cyclooxygenase and 12-lipoxygenase. In conclusion, the results indicate that catalysis of cyclooxygenase and 12-lipoxygenase in A431 cells was regulated by redox-reaction, and PHGPx seems to play an important role in the controlling of these reactions.