Direct search for Dirac magnetic monopoles in pp collisions at square root s = 1.96 TeV

We search for pair-produced Dirac magnetic monopoles in 35.7 pb(-1) of proton-antiproton collisions at square root s = 1.96 TeV with the Collider Detector at Fermilab (CDF). We find no monopole candidates corresponding to a 95% confidence-level cross-section limit sigma < 0.2 pb for a monopole with mass between 200 and 700 GeV/c2. Assuming a Drell-Yan pair-production mechanism, we set a mass limit m > 360 GeV/c2.

Measurement of the ratios of branching fractions and

We report an observation of the decay B(O)(S) --> D(-)(s)pi(+) in pp collisions at radical S = 1.96 TeV using 115 pb(-1) of data collected by the CDF II detector at the Fermilab Tevatron. We observe 83 +/- 11(stat) B(O)(s) --> D(-)(s)pi(+) candidates, representing a large increase in statistics over previous measurements and the first observation of this decay at a pp collider. We present the first measurement of the relative branching fraction Beta(B(O)(s) --> D(-)(s)pi(+))/Beta(B(0) --> D(-)(pi)(+)) = 1.32 +/- 0.18(stat) +/- 0.38(syst). We also measure Beta(B(+) --> D(0)pi(+))/Beta(B(0) -->D(-)pi(+)) = 1.97 +/- 0.10(stat) +/- 0.21(syst), which is consistent with previous measurements.

Search for scalar bottom quarks from gluino decays in collisions at

We searched for scalar bottom quarks 156 pb(-1) of pp collisions at radicalS = 1.96 recorded by the Collider Detector at Fermilab II experiment at the Tevatron. Scalar bottom quarks can be produced from gluino decays in -parity conserving models of supersymmetry when the mass of the gluino exceeds that of the scalar bottom quark. Then, a scalar bottom quark can decay into a bottom quark and a neutralino. To search for this scenario, we investigated events with large missing transverse energy and at least three jets, two or more of which were identified as containing a secondary vertex from the hadronization of quarks. We found four candidate events, where 2.6 +/- 0.7 are expected from standard model processes, and placed 95% confidence level lower limits on gluino and scalar bottom quark masses of up to 280 and 240 GeV/c(2), respectively.

Top-quark mass measurement from dilepton events at CDF II

We report a measurement of the top-quark mass using events collected by the CDF II detector from pp collisions at square root of s = 1.96 TeV at the Fermilab Tevatron. We calculate a likelihood function for the top-quark mass in events that are consistent with tt --> bl(-)nu(l)bl'+ nu'(l) decays. The likelihood is formed as the convolution of the leading-order matrix element and detector resolution functions. The joint likelihood is the product of likelihoods for each of 33 events collected in 340 pb(-1) of integrated luminosity, yielding a top-quark mass M(t) = 165.2 +/- 6.1(stat) +/- 3.4(syst) GeV/c2. This first application of a matrix-element technique to tt --> bl+ nu(l)bl'- nu(l') decays gives the most precise single measurement of M(t) in dilepton events. Combined with other CDF run II measurements using dilepton events, we measure M(t) = 167.9 +/- 5.2(stat) +/- 3.7(syst) GeV/c2.

Measurement of the inclusive jet cross section using the kT algorithm in pp collisions at (square root s)=1.96 TeV

We report on a measurement of the inclusive jet production cross section as a function of the jet transverse momentum in pp collisions at (square root s)=1.96 TeV using data collected with the upgraded Collider Detector at Fermilab in run II, corresponding to an integrated luminosity of 385 pb-1. The measurement is carried out for jets with rapidity 0.1</yjet/<0.7 and transverse momentum in the range 54<pjetT<700 GeV/c. Next-to-leading order perturbative QCD predictions are in good agreement with the measured cross section after the necessary nonperturbative parton-to-hadron corrections are included.

Measurement of the dipion mass spectrum in decays

We measure the dipion mass spectrum in X(3872)--> J/psipi(+) pi(-) decays using 360 pb(-1) of pp collisions at square root s= 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ((3)S(1), (1)P(1), and (3)D(J)) charmonia decaying to J/psipi(+) pi(-), as well as even C-parity states in which the pions are from rho(0) decay. The latter case also encompasses exotic interpretations, such as a D(0)D(*0) molecule. Only the (3)S(1) and J/psirho hypotheses are compatible with our data. Since (3)S(1) is untenable on other grounds, decay via J/psirho is favored, which implies C= +1 for the X(3872). Models for J/psi - rho different angular momenta L are considered. Flexibility in the models, especially the introduction of rho - omega interference, enables good descriptions of our data for both L = 0 and 1.

Search for Higgs bosons decaying to bb and produced in association with W bosons in pp collisions at square root of s = 1.96 TeV

We present a search for Higgs bosons decaying into bb and produced in association with W bosons in pp collisions at square root of s = 1.96 TeV. This search uses 320 pb(-1) of the data set accumulated by the upgraded Collider Detector at Fermilab. Events are selected that have a high-transverse momentum electron or muon, missing transverse energy, and two jets, at least one of which is consistent with the hadronization of a b quark. Both the number of events and the dijet mass distribution are consistent with standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching ratio for the Higgs boson or any new particle with similar decay kinematics. These upper limits range from 10 pb for mH = 110 GeV/c2 to 3 pb for mH = 150 GeV/c2.

Evidence for the exclusive decay B(c)+- --> J/psi pi+- and measurement of the mass of the B(c)+- meson

We report the first evidence for a fully reconstructed decay mode of the B(c)+- meson in the channel B(c)+- --> J/psi pi+-, with J/psi --> mu+ mu-. The analysis is based on an integrated luminosity of 360 pb(-1) in pp collisions at 1.96 TeV center of mass energy collected by the Collider Detector at Fermilab. We observe 14.6 +/- 4.6 signal events with a background of 7.1 +/- 0.9 events, and a fit to the J/psi pi+-mass spectrum yields a B(c)+- mass of 6285.7 +/- 5.3(stat) +/- 1.2(syst) MeV/c2. The probability of a peak of this magnitude occurring by random fluctuation in the search region is estimated as 0.012%.

Search for charged Higgs bosons from top quark decays in pp collisions at square root s=1.96 TeV

We report the results of a search for a charged Higgs boson in the decays of top quarks produced in pp collisions at a center-of-mass energy of 1.96 TeV. We use a data sample corresponding to an integrated luminosity of 193 pb-1 collected by the upgraded Collider Detector at Fermilab. No evidence for charged Higgs production is found, allowing 95% C.L. upper limits to be placed on BR(t-->H+b) for different charged Higgs decay scenarios. In addition, we present in the minimal supersymmetric standard model (mH+/-, tanbeta) plane the first exclusion regions with radiative and Yukawa coupling corrections.

Precision top-quark mass measurement in the lepton+jets topology in p p collisions at square root s=1.96 TeV

We report two measurements of the top-quark mass M(top) using the CDF II detector at the Fermilab Tevatron in a 318 pb(-1) data sample of tt events in the lepton+jets final state. One method uses an event-based likelihood technique resulting in M(top) = 173.2(-2.4)(+2.6)(stat) +/- 3.2(syst) GeV/c2 or 173.2(-4.0)(+4.1) GeV/c2. The second method reconstructs a top-quark mass in each event using the measured invariant mass of the hadronically decaying W boson to constrain the jet energy scale to obtain a value for M(top)of 173.5(-3.6)(+3.7)(stat) +/- 1.3(syst) GeV/c2 or 173.5(-3.8)(+3.9) GeV/c2 . We take the latter, which is more precise, as our result.

Search for neutral Higgs bosons of the minimal supersymmetric standard model decaying to tau pairs in pp collisions at square root of s = 1.96 TeV

We present a search for neutral supersymmetric Higgs bosons decaying to tau pairs produced in pp collisions at square root of s = 1.96 TeV. The data, corresponding to 310 pb(-1) integrated luminosity, were collected with the Collider Detector at Fermilab in run II of the Tevatron. No significant excess above the standard model backgrounds is observed. We set exclusion limits on the production cross section times branching fraction to tau pairs for Higgs boson masses in the range from 90 to 250 GeV/c2.

Search for new high-mass particles decaying to Lepton pairs in pp collisions at square root s = 1.96 TeV

A search for new particles (X) that decay to electron or muon pairs has been performed using approximately 200 pb(-1) of pp collision data at (square root) s = 1.96 TeV collected by the CDF II experiment at the Fermilab Tevatron. Limits on sigma(pp --> X)BR (X --> ll) are presented as a function of dilepton invariant mass m(ll) > 150 GeV/c2, for different spin hypotheses (0, 1, or 2). The limits are approximately 25 fb for m(ll) > GeV/c2. Lower mass bounds for X from representative models beyond the standard model including heavy neutral gauge bosons are presented.

Search for [corrected] B0(s) --> mu+ mu- and B0(d) [corrected] --> mu + mu- decays in pp collisions with CDF II

We report on a search for B0(s) --> mu+ mu- and B0(d) --> mu + mu- decays in pp collisions at square root(s) = 1.96 TeV using 364 pb(-1) of data collected by the CDF II detector at the Fermilab Tevatron Collider. After applying all selection requirements, we observe no candidates inside the B0(s) or B0(d) mass windows. The resulting upper limits on the branching fractions are B(B0(s) --> mu+ mu-) < 1.5 x 10(-7) and B(B0(d) --> mu+ mu-) < 3.9 x 10(-8) at 90% confidence level.

Exercise-induced myocardial ischaemia complicated by paroxysmal complete atrioventricular block

This study describes a case of exercise-induced myocardial ischaemia accompanied by complete atrioventricular block (CAVB). A 59-year-old man with major depression, treated with regular imipramine and lithium for 20 years, experienced syncope episodes during exercise. Exercise, testing initially, identified ST depression in the inferior leads, and later found CAVB resulting in syncope and seizure. The patient recovered completely after resuscitation. Myocardial ischaemic markers were negative, but 35% stenosis was detected in the distal left main coronary artery by angiography. The combined use of verapamil, nitrate and aspirin was treated as the possible coronary spasm. Repeat treadmill caused negative ischaemic study or exercise-induced arrhythmia, 7 days later. The pathophysiology of the very rare exercise-induced paroxysmal CAVB has been reviewed.

Apoptosis in primary cardiac tumours

Apoptosis, or programmed cell death, is now recognised as an important cellular event during both normal development and specific disease progression. Apoptosis has been suggested to play a critical role in several cardiovascular diseases, but has not yet been identified as a major influence in primary cardiac tumours. A retrospective review of the achieved material at Chang Gung Memorial Hospital revealed seven patients with cardiac myxoma and one with a tumour originating from the crista terminalis, from January 2002 to December 2002. The medical chart, surgical pathology reports and microscopic slides were available in all cases. All patients, including eight cardiac myxomas and one tumour from crista terminalis, were assessed for apoptosis by terminal deoxynucleotidyl transferase nick-end labelling assay. In this study, apoptosis is well documented in all seven myxoma and has even been reported in tumour from the crista terminalis. Interestingly, apoptosis appears related to the nature of the cell properties rather than the incidence of embolism. In conclusion, apoptosis is important in the progression of the primary cardiac tumours, but the mechanism of cardiac tumour regression still remains uncertain.

Observation of B(+)-->pppi+, B0-->ppK0, and B(+)-->ppK(*+)

We report the first observation of a b-->u type charmless baryonic B decay, B+-->pppi(+), as well as b-->s type B0-->ppK0 and B+-->ppK(*+) decays. The analysis is based on a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. We find B(B+-->pppi(+))=(3.06(+0.73)(-0.62)+/-0.37)x10(-6), B(B0-->ppK0)=(1.88(+0.77)(-0.60)+/-0.23)x10(-6), and B(B+-->ppK(*+))=(10.3(+3.6+1.3)(-2.8-1.7))x10(-6). We also update B(B+-->ppK+)=(5.66(+0.67)(-0.57)+/-0.62)x10(-6) and present an upper limit on B(B0-->ppK(*0)) at the 90% confidence level. A common feature of the observed decay modes is threshold peaking in baryon pair invariant mass.

Mucin gene expression in cardiac myxoma

Myxoma is the most common benign neoplasm of the heart. This work is the first to present an unusual left atrium and mitral valve cardiac myxoma which cannot be completely resected. This cardiac myxoma was also associated with abundant mucopolysaccharidic matrix, including mucin. Mucin gene expression is cell- and tissue-specific, with variations during cell differentiation and inflammation, and is altered during carcinogenesis. The expression of mucin genes in cardiac myxoma has never been elucidated previously. Detailed immunohistochemical analysis of MUC1, MUC2 and MUC5AC has been performed in this left atrium and mitral valve myxoma. Notably, the expressions of mucins in cardiac myxoma must be further evaluated.

A defect in the Kv channel-interacting protein 2 (KChIP2) gene leads to a complete loss of I(to) and confers susceptibility to ventricular tachycardia

KChIP2, a gene encoding three auxiliary subunits of Kv4.2 and Kv4.3, is preferentially expressed in the adult heart, and its expression is downregulated in cardiac hypertrophy. Mice deficient for KChIP2 exhibit normal cardiac structure and function but display a prolonged elevation in the ST segment on the electrocardiogram. The KChIP2(-/-) mice are highly susceptible to the induction of cardiac arrhythmias. Single-cell analysis revealed a substrate for arrhythmogenesis, including a complete absence of transient outward potassium current, I(to), and a marked increase in action potential duration. These studies demonstrate that a defect in KChIP2 is sufficient to confer a marked genetic susceptibility to arrhythmias, establishing a novel genetic pathway for ventricular tachycardia via a loss of the transmural gradient of I(to).

Ablation of Cypher, a PDZ-LIM domain Z-line protein, causes a severe form of congenital myopathy

Cypher is a member of a recently emerging family of proteins containing a PDZ domain at their NH(2) terminus and one or three LIM domains at their COOH terminus. Cypher knockout mice display a severe form of congenital myopathy and die postnatally from functional failure in multiple striated muscles. Examination of striated muscle from the mutants revealed that Cypher is not required for sarcomerogenesis or Z-line assembly, but rather is required for maintenance of the Z-line during muscle function. In vitro studies demonstrated that individual domains within Cypher localize independently to the Z-line via interactions with alpha-actinin or other Z-line components. These results suggest that Cypher functions as a linker-strut to maintain cytoskeletal structure during contraction.

Low prevalence of coronary arterial disease in Chinese adults with mitral stenosis

BACKGROUND

We attempted to evaluate the prevalence of coronary artery disease in Chinese adults with severe rheumatic mitral stenosis.

METHODS

We prospectively performed coronary angiography in 119 consecutive Chinese patients older than 40 years old (mitral valve area less than 1.5 cm2) who were about to undergo balloon mitral commissurotomy for significant rheumatic mitral stenosis. The exclusion criteria were the presence of left atrial cavitary thrombi or mitral regurgitation greater than grade 3.

RESULTS

There were 32 men (26%) and 87 women (74%) with a mean age of 55 +/- 9.7 years (ranging from 40 to 78). Ninety-two patients (77%) were in atrial fibrillation. The prevalence of risk factors for atherosclerotic cardiovascular disease were hypertension (22%), diabetes mellitus (4%), hypercholesterolemia > or = 240 mg/dL (5%), hypertriglyceridemia > or = 150 mg/dL (13%), and cigarette use (7%). Coronary artery disease on angiography was defined as stenosis of more than 50% of the luminal diameter. We found that only 2 patients (1.7%) had coronary artery disease.

CONCLUSION

The prevalence of coronary artery disease was much lower than in previous reports, some of which, however, had already pointed out the relatively low prevalence of coronary artery disease in rheumatic mitral disease. The definite mechanisms require further study.

Sinoatrial nodal artery aneurysm with right ventricular outflow tract compression: report of a case

We described a 16-year-old boy with sinoatrial nodal (SAN) artery aneurysm that drained into right atrium and compressed right ventricular outflow tract. The patient was clinically asymptomatic. Hemodynamic study revealed a 15 mm Hg peak systolic pressure gradient at right ventricular outflow tract. The fistula was successfully excised without sequalae. Cathet. Cardiovasc. Intervent. 51:328-331, 2000.

FHL2 (SLIM3) is not essential for cardiac development and function

LIM domain-containing proteins play critical roles in vertebrate development and cellular differentiation. Recently, four members of the four and one-half LIM protein (FHL) family have been identified and cloned. One of these, FHL2, is expressed in a restricted manner in the cardiovascular system throughout development into adulthood, suggesting that FHL2 may play an important role in cardiovascular development and function. Here we describe the generation and analysis of mice carrying a null mutation of the FHL2 gene. FHL2-deficient mice are viable and maintain normal cardiac function both before and after acute mechanical stress induced by aortic constriction. These data suggest that FHL2 is not essential for cardiac development and function.

Expression patterns of FHL/SLIM family members suggest important functional roles in skeletal muscle and cardiovascular system

LIM domain containing proteins play critical roles in animal development and cellular differentiation. Here, we describe the cloning and expression patterns of three members of the four and a half LIM domain-only protein family, FHL1, 2, and 3, from mouse. A comparison of embryonic expression patterns of these three highly-related genes indicates that they are expressed in an overlapping pattern in the developing cardiovascular system, and skeletal muscle. In adult tissues, the three genes are expressed in a predominant and overlapping manner in cardiac and skeletal muscle. Of the three genes, FHL2 appears to have the most restricted expression pattern during development, in heart, blood vessels, and skeletal muscle. Expression in heart is highest in cardiac septa and in the region adjacent to the atrio-ventricular ring, suggesting a potential role in septation or conduction system development. In the heart, FHL1expression was observed strongly in developing outflow tract, and to a lesser extent in myocardium. FHL3 displays low and ubiquitous expression during mouse development. Cardiac ventricular expression of FHL1, but not FHL2 or FHL3, was upregulated in two mouse models of cardiac hypertrophic and dilated cardiomyopathy. Taken together, these data indicate the potential importance of this FHL family in the development and maintenance of the cardiovascular system and striated muscle, and suggest that FHL1 may play a role in the development of heart disease.

Obstructive hypertrophic cardiomyopathy in Taiwanese adults

The purpose of this study was to analyze the clinical profiles, echocardiographic findings, and mortality among adult Taiwanese patients with obstructive hypertrophic cardiomyopathy (HCM) at Chang Gung Memorial Hospital, a university-affiliated tertiary referral center in suburban Taipei. We reviewed the medical records of all adult (> 15 years of age) patients referred to our laboratory for echocardiographic examinations of cardiac diseases from May 1990 through December 1996. The diagnosis of obstructive HCM required an outflow gradient of above 10 mm Hg and the presence of asymmetric septal hypertrophy of the left ventricle. Follow-up information on was obtained from hospital records, questionnaires, interviews, or the National Death Certificate Registry. Of the 6.798 adults who underwent echocardiographic examinations during the study period 122 (1.79%) had obstructive HCM. The mean +/- standard deviation age of the patients was 62.2 +/- 12.6 years, and females predominated (n = 76, 62.3%). During the mean follow-up period of 3.2 years, the annual all-cause mortality rate was 4.7%. Most deaths were due to concurrent medical conditions. The annual cardiac mortality rate was 0.99%. Logistic regression analysis identified medication with calcium channel blockers as the only negative predictor (relative risk = 0.26, 95% confidence interval = 0.07-0.96) of all-cause mortality, and left atrial size as the only positive predictor (relative risk = 1.18, 95% confidence interval = 1.02-1.37) of cardiac mortality. Cox regression analysis confirmed the former association, but not the latter. Thus, in our institution, obstructive HCM had a low prevalence among adult patients referred for echocardiographic examination. These patients were elderly and often had other associated medical conditions. The high all-cause mortality rate was largely due to non-cardiac causes. These findings suggest that obstructive HCM tends to have a benign clinical course. Large atrial size could be an independent predictor of cardiac mortality, but this possibility requires further confirmation.

Gender differences in the presentation of adult obstructive hypertrophic cardiomyopathy with resting gradient: a study of 122 patients

The present study investigated gender differences among adult patients with obstructive hypertrophic cardiomyopathy (OHCM) and resting gradient. Using outflow gradients >10 mmHg and the presence of asymmetrical septal hypertrophy of the left ventricle as inclusion criteria, 122 patients were identified among patients referred for echocardiographic examinations between May 1990 and October 1996. Clinical, echocardiographical and follow-up data were compared between male and female patients. The female patients were significantly older than male patients (mean age +/-SD 66.7+/-10.5 vs 54.8+/-12.5 years). The female patients had a smaller interventricular septal wall thickness, less frequent systolic anterior movement of the mitral valve, more frequent association with hypertension, and less frequent association with ischemic heart disease (IHD) and giant T wave inversion. In this study population, adult female patients presented with OHCM 12 years later than males. Whether this represents female patients' reluctance to seek medical attention early, a different disease process that affects predominantly elderly females, or a gender-specific end organ response to aging, hypertension, IHD and other processes, or the protective effects of estrogen remains to be determined.