Inhibition of Kirsten-ras expression in human colorectal cancer using rationally selected Kirsten-ras antisense oligonucleotides

Kirsten-ras is frequently mutated in colorectal cancers and may be an important therapeutic target, particularly because we have previously shown that acquisition of a mutation is associated with a poorer outcome. Understanding the role of Kirsten-ras and the consequences of inhibiting its activity or expression will contribute to our comprehension of colorectal cancer biology and may help to rationalize the choice of molecular targets suitable for therapeutic manipulation. Therefore we undertook a simple screen, incubating a library of oligonucleotides with Kirsten-ras mRNA and RNase H to identify an antisense oligonucleotide that effectively inhibited Kirsten-ras expression. We show for the first time in a human colon cancer cell line that inhibition of Kirsten-ras expression inhibits constitutive phosphorylation of Erk1/2, but not c-Akt, suggesting that in these cells constitutive phosphorylation of Erk 1/2 is dependent upon Kirsten-ras. Successful inhibition of Kirsten-ras had little effect on cell number or cell death and there was no evidence for accumulation of cells in any particular phase of the cell cycle. Kirsten-ras inhibition significantly reduced secretion of VEGF-A165 into the culture medium. Gene expression profiling by microarray detected altered expression of a number of genes. Of particular interest for future studies was the altered expression of genes encoding products involved in protein trafficking and the potential effects of these changes on cell adhesion. Our results suggest that, at least in this model, Kirsten-ras may contribute to malignancy predominantly through effects on angiogenesis, invasion, and metastasis, and that therapies directed at Kirsten-ras, including antisense approaches, may have particular utility through these mechanisms.

Measurement of J/psi production in continuum e(+)e(-) annihilations near square root of s = 10.6 GeV

The production of J/psi mesons in continuum e(+)e(-) annihilations has been studied with the BABAR detector at energies near the Upsilon(4S) resonance. The mesons are distinguished from J/psi production in B decays through their center-of-mass momentum and energy. We measure the cross section e(+)e(-)-->J/psi X to be 2.52+/-0.21+/-0.21 pb. We set a 90% C.L. upper limit on the branching fraction for direct Upsilon(4S)-->J/psi X decays at 4.7 x 10(-4).

Measurement of the decays B--> phiK and B--> phiK*

We have observed the decays B--> phiK and phiK(*) in a sample of over 45 million B mesons collected with the BABAR detector at the PEP-II collider. The measured branching fractions are B(B+--> phiK+) = (7.7(+1.6)(-1.4)+/-0.8)x10(-6), B(B0--> phiK0) = (8.1(+3.1)(-2.5)+/-0.8)x10(-6), B(B+--> phiK(*+)) = (9.7(+4.2)(-3.4)+/-1.7)x10(-6), and B(B0--> phiK(*0)) = (8.7(+2.5)(-2.1)+/-1.1)x10(-6). We also report the upper limit B(B+--> phipi(+))<1.4x10(-6) ( 90% C.L.).

Measurement of branching fractions and search for CP-violating charge asymmetries in charmless two-body B decays into pions and kaons

We present measurements, based on a sample of approximately 23x10(6) BB pairs, of the branching fractions and a search for CP-violating charge asymmetries in charmless hadronic decays of B mesons into two-body final states of kaons and pions. We find the branching fractions B(B0-->pi(+)pi(-)) = (4.1+/-1.0+/-0.7)x10(-6), B(B0-->K+pi(-)) = (16.7+/-1.6+/-1.3)x10(-6), B(B+-->K+pi(0)) = (10.8(+2.1)(-1.9)+/-1.0)x10(-6), B(B+-->K0pi(+)) = (18.2(+3.3)(-3.0)+/-2.0)x10(-6), B(B0-->K0pi(0)) = (8.2(+3.1)(-2.7)+/-1.2)x10(-6). We also report 90% confidence level upper limits for B meson decays to the pi(+)pi(0), K+K-, and K0K+ final states. In addition, charge asymmetries have been found to be consistent with zero, where the statistical precision is in the range of +/-0.10 to +/-0.18, depending on the decay mode.

Day-night variations in blood levels of nitric oxide, T-TFPI, and E-selectin

Circadian (8/24 hours) variations in serum nitric oxide (NO), total tissue factor pathway inhibitor (T-TFPI). and E-selectin levels were studied in healthy adults and in subjects with type II diabetes. We postulated a possibility a functional relationship between them because vascular endothelium is the primary site of their synthesis and functions. NO is released by the action of eNO synthase isoform and modulates physiologic responses (e.g., vascular dilation, relaxation, increasing blood flow, inhibition of platelet and white blood cell adhesion); T-TFPI, a coagulation inhibitor, is also released from endothelial cells, and is bound to plasma lipoproteins and to glycosaminoglycans; E-selectin is expressed on endothelial cells after activation by inflammatory cytokines (interleukin-1beta and tumor necrosis factor-alpha) and elevated levels have been reported in a variety of pathologic conditions, including diabetes. We found that obese diabetic subjects had greater mean concentrations of NO and E-selectin than healthy men, 39.25 versus 12.71 microM and 81.51 versus 26.03 ng/mL, respectively. The T-TFPI levels were essentially similar in both groups of men, 47.10 versus 48.76 ng/mL. We observed that the time of peak concentrations of T-TFPI and E-selectin was similar to the timing of NO trough levels, suggesting a possible functional relationship. It may be hypothesized, therefore, that the higher concentrations of NO, unbalanced by increases in T-TFPI and E-selectin, may result in increased vascular wall uptake of lipoproteins in diabetic subjects, who are at greater risk than healthy men for developing diffuse atherosclerosis.

The challenge of culturally competent health care: applications for asthma

To better serve the increasingly diverse ethnic and racial communities in the United States, health care professionals must develop a knowledge base of cultural health practices. In asthma, a common disease, ethnic minority populations experience poorer outcomes when compared with whites. It is, therefore, imperative that providers have an improved understanding of how patients make decisions concerning their health. Cultural health practices, in concert with conventional treatments, often form a comprehensive asthma management strategy for the patient. The potential implication of alternative explanations for disease, as well as the role of diet and botanical supplements, is explored in this article in an effort to increase providers' sensitivity to nonbiomedical models of disease causality. This sensitivity is the first step in developing cultural competency.

Observation of CP violation in the B(0) meson system

We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of Upsilon(4S) decays collected in 2001, bringing the data available to 32 x 10(6) BB macro pairs. We select events in which one neutral B meson is fully reconstructed in a final state containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2 beta, is derived from the decay time distributions in such events. The result sin2 beta = 0.59+/-0.14(stat)+/-0.05(syst) establishes CP violation in the B(0) meson system. We also determine absolute value of lambda = 0.93+/-0.09(stat)+/-0.03(syst), consistent with no direct CP violation.

An open-label, uncontrolled dose-optimization study of sublingual apomorphine in erectile dysfunction

BACKGROUND

Because apomorphine is a dopamine agonist that acts on areas of the central nervous system believed to mediate penile erection, its use in erectile dysfunction (ED) has been investigated. However, it also produces nausea by dopamine-receptor stimulation of the chemotrigger zone in the brain. Therefore, a low plasma concentration, achieved rapidly, would be selective for the desired erectile response but would be below the dopamine threshold for nausea.

OBJECTIVE

We evaluated the efficacy and tolerability of a dose-optimized regimen of a sublingual formulation of apomorphine (apomorphine SL) in the treatment of ED.

METHODS

This was a multicenter, open-label, uncontrolled, Phase III dose-optimization study of apomorphine SL in heterosexual men with ED. The 2-week screening period, during which baseline severity of ED was determined using the International Index of Erectile Function, was followed by a 3-week dose-optimization period beginning at a dose of 2 mg. Patients were to make at least 2 attempts at intercourse per week throughout the study, placing 1 apomorphine tablet under the tongue beforehand. At the end of the first week, the dose could be increased to 3 mg at the discretion of the investigator; at the end of the second week, the dose could be increased to a maximum of 4 mg or decreased as needed. In the following 4-week treatment period, patients took their individual optimal doses. The primary efficacy variable was the percentage of attempts resulting in erections firm enough for intercourse, as assessed by investigators' review of data from patients' diaries. Secondary variables included the percentage of attempts resulting in successful intercourse, time to erection, and duration of erection. Information about adverse events, including their severity and relation to treatment, was determined on the basis of direct questioning, spontaneous reports, and review of patient diaries.

RESULTS

The study enrolled 849 heterosexual men whose ages ranged from 31 to 78 years (mean, 58.1 years). They had a mean 5.7-year history of ED of varbus causes. ED was mild in 11.5% of the men, moderate in 23.8 c, and severe in 48.1%. When results of the last 8 attempts were pooled, representing the period during which patients were taking their optimal doses of apomorphine SL, the mean percentage of attempts resulting in erections firm enough for intercourse was 39.4%, compared with 13.1% at baseline; attempts resulting in intercourse increased from a mean of 12.7% at baseline to 38.3% with treatment. The average median time to erection was 23 minutes, and the average median duration of erection was 13 minutes. Nausea, the most common treatment-related adverse event (11.7%). was dose related and diminished with continued dosing. One patient had a single syncopal episode that was judged to be related to apomorphine SL.

CONCLUSIONS

In the present study, a dose-optimization regimen of apomorphine SL-with dosing initiated at 2 mg and adjusted up to a maximum of 4 mg as needed-was effective and well tolerated in the treatment of ED, regardless of its cause or severity.

Effects of semiconductor substrate and glia-free culture on the development of voltage-dependent currents in rat striatal neurones

An essential requirement for successful long-term coupling between neuronal assemblies and semiconductor devices is that the neurones must be able to fully develop their electrogenic repertoire when growing on semiconductor (silicon) substrates. While it has for some time been known that neurones may be cultured on silicon wafers insulated with SiO2 and Si3N4, an electrophysiological characterisation of their development under such conditions is lacking. The development of voltage-dependent membrane currents, especially of the rapid sodium inward current underlying the action potential, is of particular importance because the conductance change during the action potential determines the quality of cell-semiconductor coupling. We have cultured rat striatal neurones on either glass coverslips or silicon wafers insulated with SiO2 and Si3N4 using both serum-containing and serum-free media. We here report evidence that not only serum-free culture media but also growth on semiconductor surfaces may negatively affect the development of voltage-dependent currents in neurones. Furthermore, using surface-charge measurements with the atomic force microscope, we demonstrate a reduced negativity of the semiconductor surface compared to glass. The reduced surface charge may affect cellular development through an effect on the binding and/or orientation of extracellular matrix proteins, such as laminin. Our findings therefore suggest that semiconductor substrates are not entirely equivalent to glass in terms of their effects on neuronal cell growth and differentiation.

The non-structural leader protein gene of foot-and-mouth disease virus is highly variable between serotypes

Aphthoviruses are unique among picornaviruses in that they alone encode a functional L proteinase as the first component of the viral polyprotein. The L genes of a few Indian foot-and-mouth disease viruses were sequenced and compared with those available to study the extent of variation in this gene. Besides the two in-frame start codons present in all FMDV L genes, the Asia-I vaccine virus had an additional in-frame AUG (start) codon, at codon position 3. Amino acid sequence comparison revealed that 39.8% of positions were capable of accepting replacements, yet the residues of the catalytic dyad were totally conserved. Sequence comparison at the C-terminus of the protein indicated that K/R decreasing GAGQS is sufficient for L/P1 cleavage. Phylogenetic analysis based on the L gene sequences did not reveal any serotype-specific clustering. The probable implications of the observed high variability in this non-structural gene is briefly discussed.

Double-blind, crossover comparison of 3 mg apomorphine SL with placebo and with 4 mg apomorphine SL in male erectile dysfunction

OBJECTIVE

To establish the efficacy and safety of a fixed, 3-mg dose of apomorphine SL compared with placebo, and to compare 3 mg with 4 mg apomorphine SL in patients with erectile dysfunction.

METHODS

This randomized, double-blind, crossover study included 296 heterosexual men with ED of various etiologies and severities. Two crossover groups were evaluated separately: 3 mg apomorphine SL vs. placebo (n = 194), and 3 vs. 4 mg apomorphine SL (n = 102). The primary efficacy variable was the percentage of attempts resulting in erections firm enough for intercourse; additional variables included the percentage of attempts resulting in intercourse and time to erection. Partner assessments were also analyzed.

RESULTS

3 mg apomorphine SL was significantly more effective than placebo (p<0.001) for the percentage of attempts resulting in erections firm enough for intercourse and resulting in intercourse, as assessed by both patients and partners. Median time to erection was 18.8 min. The 3-mg dose was not significantly different from 4 mg in the evaluation of efficacy variables, but the incidence of adverse events was higher with 4 mg. Nausea was the most common event, reported by 3.3% of patients on 3 mg vs. 14.1% on 4 mg; in the placebo comparison, nausea was reported by 7.0% of patients taking 3 mg apomorphine SL vs. 1.1% of those taking placebo.

CONCLUSIONS

3 mg apomorphine SL was significantly more effective than placebo and comparable to 4 mg, while offering an improved risk-benefit ratio.

Low levels of thrombin activatable fibrinolysis inhibitor (TAFI) in patients with chronic liver disease

Thrombin Activatable Fibrinolysis Inhibitor (TAFI) is a 60 kappaD glycoprotein present in plasma that regulates fibrinolysis by limiting the amount of fibrin available for fibrinolysis by tissue plasminogen activator (t-PA). Chronic liver disease is well-known to be associated with a low-grade fibrinolytic syndrome that under the appropriate stimulus proceeds to an overt disseminated intravascular coagulopathy (DIC) with demonstrable bleeding. In the present study, TAFI activity was measured in the plasma of 74 patients with advanced liver disease, and the levels of TAFI were related to those of other important coagulation and fibrinolytic factors. TAFI levels were very low and essentially undetectable in the plasma of patients with advanced hepatocellular liver disease. No relationship with the degradation products of fibrin was evident.

Measurement of CP-violating asymmetries in B0 decays to CP eigenstates

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta = 0.34+/-0.20 (stat)+/-0.05 (syst).

Solitary pancreatic metastasis from a primary colonic tumor detected by PET scan: report of a case

PURPOSE

A case of a solitary pancreatic metastasis from a primary colonic carcinoma is reported.

METHODS

The history and use of carcinoembryonic antigen, computed tomography, and positron emission tomography in this case and the follow-up of colorectal cancer are reviewed.

RESULTS

Recurrent disease was suspected by an increasing carcinoembryonic antigen level. However, conventional imaging with computed tomography on more than one occasion failed to identify any recurrence. The pancreatic metastasis was accurately localized by positron emission tomography scanning and confirmed on subsequent laparotomy. A histologically complete resection was performed and the patient remained in remission with a normal carcinoembryonic antigen 12 months postoperatively.

CONCLUSION

This case reports an unusual site of solitary metastasis in colorectal cancer and supports the further investigation of positron emission tomography in follow-up of colorectal cancer.

Biphalangeal fifth toe: an increasingly common variant?

The presence of 2 phalanges in the 5th toe was first described by Leonardo da Vinci in 1492 (O’Malley & Saunders, 1952) and is recognised as a normal variant. It is probably a true anatomical variant resulting from incomplete segmentation rather than the result of phalangeal fusion (Venning, 1960; Le Minor, 1995) and has been noted to be present in fetuses from as early as 12 wk (Venning, 1960). This variant (and the much rarer 2 biphalangeal 2nd–4th toes) is an exclusively human phenomenon suggesting it is a response to bipedalism (Le Minor, 1995). Various investigators have reported the incidence of the 2 phalanged 5th toe of populations as between 35.5% and 80.4% with the lower values being seen in Europeans and the higher in Japanese (Venning, 1960; Thompson & Chang, 1995). Our study compared foot radiographs in the old and young to see if there was any difference in incidence.

Factitious hypoglycemia: a tale from the Arab world

The mother is usually the one who narrates the patient's history to the pediatrician. Listening and eliciting the parent's story is an art. One of the essential attributes of a good pediatrician is the readiness to believe the parent's story. Mothers are good historians and careful observers. The axiom that the mother is always right is true in most instances. However, occasionally the clinician is deliberately misled by the storyteller, resulting in numerous and potentially dangerous diagnostic investigations. We describe a boy with recurrent hypoglycemic coma in whom the diagnosis of factitious hypoglycemia was delayed as it is believed to be nonexistent in our community. We emphasize that in all patients with recurrent hypoglycemia, estimation of C-peptide and insulin should be performed even when the clinical settings are not in favor of the diagnosis of Munchausen syndrome by proxy. Munchausen syndrome by proxy, hypoglycemia.

Sequence analysis of the RNA polymerase gene of foot-and-mouth disease virus serotype Asia1

The complete nucleotide (nt.) sequence of the RNA polymerase (3D) gene and 81 nt. in the 3'-untranslated region of foot-and-mouth disease virus (FMDV) serotype Asial (IND63/72) was determined and compared with the sequence of other FMDV serotypes. The 3D genomic region was 1410 nt. long encoding 470 amino acids with an inframe stop codon (TAA) at nt. position 1411-1413. The deduced amino acid sequence of the protein showed 8 conserved motifs as reported in other picornaviruses, 2 of which are 100% identical across the serotypes. Antigenic regions in the polymerase protein were predicted and found to be located at the N-terminus of the protein. The phylogenetic analysis showed that the FMD viruses were segregated into different clusters based on geographical origin; the Asia1 virus did not cluster tightly with any of the geographical groups.

Metabolic activation stimulates acid production in synovial fibroblasts

OBJECTIVE

In rheumatoid arthritis (RA), synovial fibroblasts express proteases such as collagenases or cathepsins and inflammatory cytokines at elevated levels and so contribute to the inflammatory degradation process. Extracellular matrix degradation and cathepsin activity is dependent upon the presence of an acidic milieu. We examined whether activated synovial fibroblasts secrete acidic components.

METHODS

Synovial fibroblasts were isolated and immortalized to study the mechanisms of metabolic activation. Naïve and immortalized fibroblasts were activated with different cytokines. The responses were investigated by immunoblot to detect Egr-1 and by a cytosensor microphysiometer analysis to evaluate acid secretion. Basic gene expression patterns were investigated in naïve and immortalized cells by RT-PCR analysis.

RESULTS

We found RA synovial fibroblasts respond to different cytokines associated with the pathomechanisms of RA including interleukin 1, basic fibroblast growth factor, platelet derived growth factor, and tumor necrosis factor-alpha, with metabolic activation and enhanced secretion of acidic components. In addition, naive and SV40 TAg immortalized fibroblasts rapidly release acidic components after stimulation with phorbol ester or ionomycin as well.

CONCLUSION

Activated synovial fibroblasts not only express inflammatory cytokines and matrix degrading proteases that are associated with the pathomechanisms of RA, but upon stimulation may release acidic components that lower pH and consequently enhance cathepsin activity and collagen solubilization.

The safety and tolerability of candesartan cilexetil in CHF

The management of congestive heart failure (CHF) continues to represent a major therapeutic challenge. The primary goal of any treatment is the improvement of symptoms with a reduction in CHF related morbidity and a neutral or beneficial effect on mortality. The number of hospitalisations is considered an important measure of morbidity and quality-of-life in these patients. This pooled safety analysis was performed on adverse event data from five placebo-controlled studies involving a total of 1893 patients, 1287 of whom received candesartan cilexetil and 606 of whom received placebo. These were the only placebo-controlled phase II and III studies of candesartan safety available at the time of the analysis, and investigated the efficacy and safety of candesartan cilexetil in patients with CHF. None was designed as an endpoint trial. A blinded, independent review of all adverse event data was performed to assess all-cause mortality and unexpected deaths, and hospitalisations for acute deterioration of CHF, chronic progression of CHF, other intercurrent events, or accidental injury/attempted suicide. The descriptive analysis included crude and cumulative incidence rates for mortality and cardiac and non-cardiac morbidity using the Kaplan-Meier method and the log-rank test. The sample population was predominantly (approximately two thirds) male, with a median age of 61 years (range: 20-89 years). The median age for women in the sample population was 66 years (range: 26-86 years). Patients received candesartan cilexetil, 2-32 mg, over a median period of 84 days (range: 1-418 days), or placebo over a median period of 85 days (range: 1-398 days). The results demonstrated a clinically non-significant trend for all relevant events (deaths and hospitalisations, whether related to CHF or not) to occur less frequently in patients receiving candesartan cilexetil than in patients receiving placebo (deaths - candesartan cilexetil: 1.6%, placebo: 1.8%; hospitalisations - candesartan cilexetil: 7.2%, placebo: 10.9%). There was a significant treatment difference in CHF hospitalisations (candesartan cilexetil: 3.0% vs. placebo: 5.6%). The time to event analysis revealed that significantly fewer hospitalisations due to CHF occurred in the group receiving candesartan cilexetil than in the group receiving placebo. This treatment difference persisted throughout therapy (log-rank test; p < 0.028). These results show the safety of candesartan cilexetil, compared with placebo, in the treatment of patients with CHF.

The disinfection by-products dichloro-, dibromo-, and bromochloroacetic acid impact intestinal microflora and metabolism in Fischer 344 rats upon exposure in drinking water

Human consumption of chlorinated drinking water has been linked epidemiologically to bladder, kidney, and rectal cancers. The disinfection by-product (DBP) dichloroacetic acid is a hepatocarcinogen in Fischer 344 rats and B6C3F1 mice. The objective of this study is to determine the effect of the DBPs dichloro-, bromochloro-, and dibromoacetic acids (DCA, BCA, DBA) on intestinal microbial populations and their metabolism, with emphasis on enzymes involved in the bioactivation of procarcinogens and promutagens. One-month-old male Fischer 344 rats were provided water ad libitum containing 1 g/l DCA, BCA, or DBA for up to 5 weeks. At 1, 3, and 5 weeks of treatment, beta-glucuronidase (GLR), beta-galactosidase (GAL), beta-glucosidase (GLU), nitroreductase (NR), azoreductase (AR), and dechlorinase (DC) activities were determined in cecal and small and large intestinal homogenates. After 5 weeks of treatment, intestinal populations were enumerated on selective media. Cecal GAL (DCA, BCA, DBA) and GLR (DCA, DBA) activities were reduced after 1 and 3 weeks of treatment and GAL activity was elevated at 5 weeks (BCA). Large intestinal GAL (DCA, BCA) and GLU (DCA, BCA, DBA) activities were elevated after 5 weeks of treatment. Week 5 cecal AR (DCA, BCA, DBA), NR (DCA), and DC (DCA, DBA) activities were reduced. Even though some significant changes in intestinal populations were observed, use of selective media was not sensitive enough to explain fluctuations in enzyme activity. Haloacetic acids in the drinking water alter intestinal metabolism, which could influence bioactivation of promutagens and procarcinogens in the drinking water.