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.

Can the light-addressable potentiometric sensor (LAPS) detect extracellular potentials of cardiac myocytes?

The light-addressable potentiometric sensor (LAPS) measures localized photo-induced currents from a silicon wafer, which are dependent on the local surface potential and on the intensity of the light pointer. In this study the ability of the LAPS to record extracellular potentials of adherent cells was investigated. Time dependent LAPS photocurrent signals that correlated in time with contractions were recorded from beating cardiac myocytes cultured on LAPS surfaces. Signals could be recorded both when the LAPS was biased to working points where the photocurrent was maximally sensitive to potential changes and when it was biased to working points where the photocurrent was insensitive to changes in surface potential. Therefore, signals could not be predominantly created by changes in extracellular potential and might be related to mechanical contractions. One possible explanation might be, that the cell-induced modulation of photocurrents arose as a result of cell shape changes. Such alterations in cell shape might have focused and defocused the light pointer and, thus, modulated its intensity. To further test this hypothesis, height changes of beating cardiac myocytes were measured with an atomic force microscope (AFM). They were found to match well with signals derived from LAPS measurements. Therefore, it can be concluded, that LAPS signals were mainly determined by the periodic changes in shape of beating heart cells, and this interference precludes the measurements of extracellular electrophysiological potentials from these cells.

Transgenic mice overexpressing alpha2A-adrenoceptors in pancreatic beta-cells show altered regulation of glucose homeostasis

AIMS/HYPOTHESIS

To study the role of the human alpha2A-adrenoceptor in the regulation of insulin secretion and the maintenance of glucose homeostasis in transgenic mice overexpressing this receptor in pancreatic beta cells.

METHODS

A human insulin promoter/human alpha2C10-adrenoceptor chimeric gene was microinjected into mouse embryos and transgenic mice were obtained.

RESULTS

Analysis by RT-PCR showed that the expression of the transgene was restricted to pancreatic islets. Study of the binding of the alpha2-antagonist [3H]RX821002 to membrane preparations showed that islets from transgenic mice had ninefold higher alpha2-adrenoceptor density than those from controls. Immunohistological analysis showed, however, no change in the number or size of islets between control and transgenic mice. Transgenic animals had normal glycaemia and insulinaemia in basal conditions but greater hyperglycaemic and hypoinsulinaemic responses after injection of the alpha2-agonist, UK14304. The lower blood insulin concentration detected in transgenic mice was a reflection of a stronger inhibitory effect of the alpha2-agonist on glucose-stimulated insulin secretion in transgenic islets than in controls. Furthermore, transgenic mice did not have lower glycaemia to basal values after an intraperitoneal glucose tolerance test. This defect was abolished by treatment with the alpha2-adrenoceptor antagonist, RX821002.

CONCLUSION/INTERPRETATION

These results provide evidence in vivo that overexpression of alpha2-adrenoceptors in beta cells can lead to impaired insulin secretion and glucose intolerance.

Dimethylarsinic acid treatment alters six different rat biochemical parameters: relevance to arsenic carcinogenesis

In a previous study, we found that sodium arsenite increased hepatic ornithine decarboxylase (ODC) activity and hepatic heme oxygenase (HO) activity, but did not cause any DNA damage in adult female rat liver or lung, suggesting that arsenite may be a promoter of carcinogenesis. In this study sodium arsenate, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) were administered orally in equitoxic doses to adult female rats at 21 and 4 h prior to sacrifice. DNA damage (DD), cytochrome P450 content (P450), glutathione content (GSH), ODC, serum alanine aminotransferase (ALT) and HO were measured in liver and/or lung tissue. At 60 mg/kg in rat liver, sodium arsenate increased hepatic HO fivefold. MMA decreased ALT at 226 mg/kg, decreased ALT and GSH at 679 mg/kg and also increased P450 at 679 mg/kg in rat liver. DMA decreased ALT and hepatic GSH and increased hepatic HO at 387 mg/kg. In the lung, DMA decreased ODC at both 129 and 387 mg/kg. DD in lung tissue was significantly higher at 387 mg/kg DMA, demonstrating organ specific DNA damage. The biochemical effects and the inferred oncologic potential of the four major forms of arsenic (arsenate, arsenite, MMA and DMA) differ dramatically. The inorganic forms (arsenate and arsenite) are similar to each other (both good HO inducers); the methylated organic forms of arsenic (MMA and DMA) also share a similar pattern of biochemical effects (decreased GSH and ALT, increased P450). All six of the biochemical parameters studied were altered by DMA in either rat liver or lung.

Transgenic mice overexpressing insulin-like growth factor-II in beta cells develop type 2 diabetes

During embryonic development, insulin-like growth factor-II (IGF-II) participates in the regulation of islet growth and differentiation. We generated transgenic mice (C57BL6/SJL) expressing IGF-II in beta cells under control of the rat Insulin I promoter in order to study the role of islet hyperplasia and hyperinsulinemia in the development of type 2 diabetes. In contrast to islets from control mice, islets from transgenic mice displayed high levels of IGF-II mRNA and protein. Pancreases from transgenic mice showed an increase in beta-cell mass (about 3-fold) and in insulin mRNA levels. However, the organization of cells within transgenic islets was disrupted, with glucagon-producing cells randomly distributed throughout the core. We also observed enhanced glucose-stimulated insulin secretion and glucose utilization in islets from transgenic mice. These mice displayed hyperinsulinemia, mild hyperglycemia, and altered glucose and insulin tolerance tests, and about 30% of these animals developed overt diabetes when fed a high-fat diet. Furthermore, transgenic mice obtained from the N1 backcross to C57KsJ mice showed high islet hyperplasia and insulin resistance, but they also developed fatty liver and obesity. These results indicate that local overexpression of IGF-II in islets might lead to type 2 diabetes and that islet hyperplasia and hypersecretion of insulin might occur early in the pathogenesis of this disease.

Candesartan Cilexetil, a Novel Angiotensin II Antagonist, Provides Dose-dependent Antihypertensive Effect with Maintained Tolerability

Candesartan is a new angiotensin II type 1 (AT 1 ) receptor blocker that binds tightly to and dissociates slowly from the AT 1 -receptor. It is administered as a prodrug, candesartan cilexetil, which is completely converted to the active compound, candesartan, during absorption in the gastrointestinal tract. Placebo-controlled studies have shown that candesartan cilexetil is an effective antihypertensive drug. The individual studies, however, lacked the statistical power to assess the dose-response relationship with high precision. A more precise estimate of the effect of different doses may be achieved by pooling similar studies in a meta-analysis. The primary objective of this meta-analysis was to determine the dose-response relationship for the antihypertensive effect of candesartan cilexetil. Six European randomized, double-blind, placebo-controlled, dose-response studies with candesartan cilexetil were reported by 30 September 1996. These studies enrolled similar patients (primary hypertension with a sitting diastolic blood pressure [DBP] of 95-114 mmHg after a placebo run-in period) and had a similar design (parallel groups and fixed doses). The doses investigated ranged from 2 to 16 mg once daily. All doses were not given in every study, but all studies investigated at least two different doses of candesartan cilexetil. The duration of the double-blind phase varied between studies, but was at least 4 weeks (range: 4-12 weeks). The variable of primary interest was sitting DBP measured 24 h after dose (trough effect). Each dose of candesartan was analysed separately, and compared with placebo data only from those studies in which that dose was given. The analysis was performed using an analysis of covariance model. Placebo-corrected estimated mean blood pressure reductions from baseline (randomization) to the end of the study and the 95% confidence intervals for the true mean reductions were calculated for each dose. In total, 1498 hypertensive patients were randomized, of whom 1482 provided efficacy data and were included in the analysis. The vast majority of patients (99%) were of Caucasian origin. The placebo-corrected reductions in sitting DBP and sitting systolic blood pressure (SBP) achieved with the different doses of candesartan cilexetil are shown in the Table. Reductions in blood pressure were dose-related, and age or gender did not influence the antihypertensive effect of candesartan cilexetil. Furthermore, blood pressure reductions achieved in the standing position were similar to those in the sitting position, i.e. there was no indication of an abnormal orthostatic response during treatment with candesartan cilexetil. Heart rate was not significantly influenced by candesartan cilexetil. Adverse events occurred in a similar proportion of patients treated with placebo or candesartan cilexetil and did not increase with the dose. Candesartan cilexetil was equally well tolerated in young and elderly patients and in men and women. Thus, in European patients with mild to moderate hypertension, candesartan cilexetil provides a clinically significant, dose-dependent, antihypertensive effect in doses ranging from 4 to 16 mg once daily. The optimal maintenance doses of candesartan cilexetil appear to be 8 or 16 mg once daily in most patients.

Improvement in exercise tolerance and symptoms of congestive heart failure during treatment with candesartan cilexetil. Symptom, Tolerability, Response to Exercise Trial of Candesartan Cilexetil in Heart Failure (STRETCH) Investigators

BACKGROUND

The renin-angiotensin system plays an important part in the pathogenesis of congestive heart failure (CHF). This study evaluated the effect of an angiotensin II type 1 receptor antagonist on exercise tolerance and symptoms of CHF.

METHODS AND RESULTS

In this multicenter, double-blind, parallel-group study, 844 patients with CHF were randomized to 12 weeks' treatment with placebo (n=211) or candesartan cilexetil 4 mg (n=208), 8 mg (n=212), or 16 mg (n=213) after a 4-week placebo run-in period. Changes in exercise time, Dyspnea Fatigue Index score, NYHA functional class, and cardiothoracic ratio were determined. Candesartan cilexetil produced a dose-related improvement in exercise time. For the intention-to-treat population, the increase produced by candesartan cilexetil 16 mg was significantly greater than that produced by placebo (47.2 versus 30.8 seconds, P=0.0463). All doses of candesartan cilexetil significantly improved the Dyspnea Fatigue Index score relative to placebo. NYHA class improved more frequently in the candesartan cilexetil groups; the differences relative to placebo were not significant. The decrease in cardiothoracic ratio with candesartan 4 to 16 mg was small but statistically significant compared with placebo (all P<0.05). In all candesartan cilexetil groups, plasma renin activity and angiotensin II levels increased from baseline and aldosterone levels decreased in the 8- and 16-mg treatment groups. Candesartan cilexetil was well tolerated at all doses.

CONCLUSIONS

In summary, treatment with candesartan cilexetil demonstrated significant improvements in exercise tolerance, cardiothoracic ratio, and symptoms and signs of CHF and was well tolerated.

[Anesthesia consultation in cardiovascular and thoracic surgery. A survey of patient and physician satisfaction]

OBJECTIVE

To assess the quality of the preadmission anaesthetic consultation prior to cardiovascular and thoracic surgery with a satisfaction inquiry.

STUDY DESIGN

Prospective study with a questionnaire, extended over a period of two months.

PERSONS

Patients and anaesthetists of the cardiothoracic surgical service.

METHODS

The inquiry, which took place after completion of the consultation was achieved by a person non member of the staff. Anaesthetists were questioned on the medical content, its exhaustive character and its value for the patient's perioperative care.

RESULTS

Out of the 273 patients included in the study, 121 agreed to answer the questionnaire. Participation in the study was more significant in older patients (58 +/- 20 vs 51 +/- 24 years) and following shorter waiting time (WT) [15 +/- 13 (0-60) vs 25 +/- 18 (0-66) min]. The duration of the consultation (DC) was not different between the two groups [29 +/- 12 (8-70) vs 31 +/- 14 (6-75) min]. However patients' participation increased when the DC exceeded by 0.6 the sum of DC and WT [DC > 0.6 (DC + WT)]. The analogic score (AS) assessing reduction in preoperative anxiety was 8.4 +/- 1.5 (2-10). Finally, 108 patients out of 121 considered to have been well informed about the anaesthetic [AS = 8.7 +/- 1.2 (4-10)], 113 considered the preadmission consultation as a useful procedure [AS = 8.6 +/- 1.5 (2-10)]) and for 41 a personalized follow-up by the same anaesthetist was valuable. Only three operations had to be postponed the day before surgery. One third of the anaesthetists considered that the consultation improved the clinical and therapeutic management of the patients.

CONCLUSION

This inquiry showed that the preadmission anaesthesia consultation was considered as benefitful by patients and anaesthetists. However the participation of patients in this study was poor. Subsequently to the inquiry information forms have been produced and handed to the patient prior to the consultation.

Simultaneous monitoring of argatroban and its major metabolite using an HPLC method: potential clinical applications

Argatroban is a peptidomimetic inhibitor of thrombin that is currently undergoing extensive clinical trials as a heparin substitute for thrombotic complications. Argatroban is readily metabolized into a major derivative, M1, that has pharmacological characteristics distinct from its parent compound. The currently available clot-based assays measure the cumulative anticoagulant effect of argatroban and its metabolite(s). Available HPLC methods do not differentiate between argatroban and M1-metabolite. A modified method was developed to simultaneouly quantitate M1-metabolite and argatroban in biological fluids. Initial validation studies for the method included clinical trials of argatroban in patients with heparin-induced thrombocytopenia, (ARG 911 Study) and coronary interventional procedures (ARG 310 Study). Plasma samples were extracted with acetonitrile and reconstituted in a mobile phase. Calibration curves were prepared by running known standards of argatroban and M1-metabolite in normal human plasma. Ultraviolet detection was made at 320 nm. The retention times for argatroban and M1-metabolite peaks were found to be 10.5 +/- 0.3 minutes and 3.9 +/- 0.1 minutes, respectively. The extraction efficiency was > 95% (r2 = 0.99). In heparin-induced thrombocytopenia patients with major bleeding complications (n = 30), the relative increase in M1-metabolite compared to argatroban varied widely (two- to eight-fold). The mean concentration of argatroban during the steady infusion period was found to be 0.7 +/- 0.35 microgram/mL, and for M1-metabolite, it was 5.5 +/- 2.8 micrograms/mL. Proportionate results were not seen when higher dosages of argatroban were administered (coronary angioplasty studies). Argatroban and M1-metabolite levels also compared well with the results in global clotting assays. Owing to the simultaneous quantitation of argatroban and M1-metabolite, this method provides a rapid assessment of the pharmacokinetics and pharmacodynamics of argatroban. The differential quantitation may be useful in the assessment of relative metabolic turnover of argatroban that can be related to the hepatic and renal functions in a given patient.