Carcinoid tumor of the spleen: report of a case

Carcinoid tumors are uncommon tumors of the neuroendocrine system. They grow slowly and may remain silent for years before presenting with carcinoid syndrome. A diagnosis of asymptomatic carcinoid tumor is difficult. Wide resection of the primary tumor and metastatic lesions is the first choice of treatment. Primary carcinoid is sometimes distributed throughout the entire body, but it is rare in the spleen. We herein present a rare case of a symptomless carcinoid tumor that predominantly invaded the spleen with liver metastasis.

Search for new physics in photon-lepton events in pp collisions at sqrt[s] = 1.8 TeV

We present the results of a search in pp collisions at sqrt[s] = 1.8 TeV for anomalous production of events containing a photon and a lepton (e or mu), both with large transverse energy, using 86 pb(-1) of data collected with the Collider Detector at Fermilab during the 1994-1995 collider run at the Fermilab Tevatron. The presence of large missing transverse energy (E(T)), additional photons, or additional leptons in these events is also analyzed. The results are consistent with standard model expectations, with the possible exception of photon-lepton events with large E(T), for which the observed total is 16 events and the expected mean total is 7.6+/-0.7 events.

Multicenter surveillance of antimicrobial resistance of major bacterial pathogens in intensive care units in 2000 in Taiwan

A susceptibility surveillance study of 1,274 bacterial isolates recovered from various clinical specimens from patients in intensive care units (ICUs) of five major teaching hospitals was carried out from March, 2000, to June, 2000, in Taiwan. This study demonstrated a high rate (66%) of oxacillin resistance in Staphylococcus aureus (ORSA), a high rate of nonsusceptibility to penicillin (intermediate, 50% and highly resistant, 8%), and high rates of cefotaxime nonsusceptibility for S. pneumoniae (intermediate, 29% and resistant, 4%), Enterobacter cloacae (57%), Serratia marcescens (34%), and Citrobacter freundii (60%). High rate of ceftazidime nonsusceptibility for Pseudomonas aeruginosa (22%), and high rates of imipenem nonsusceptibility for P. aeruginosa (15%) and Acinetobacter baumannii (22%) were also found. The percentage (11.9%) of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was greater than that (11.3%) for Klebsiella pneumoniae. Rates of quinupristin-dalfopristin nonsusceptibility for S. pneumoniae (42%), Enterococcus faecium (71%), and ORSA (39%) were high, but no vancomycin-resistant enterococci were found in this study. The resistance rates of some pathogen varied by institution or type of ICUs. Surveillance for antimicrobial resistance among bacterial pathogens in hospitals, particularly in ICU settings with a preexisting higher resistance burden, is mandatory in establishing and/or modifying guidelines for empirical treatment of severe infections in ICU patients caused by these antimicrobial-resistant pathogens.

Upsilon production and polarization in p p macro collisions at square root of s = 1.8 TeV

We report on measurements of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections (d(2)sigma/dp(T)dy)(/y/<0.4), as well as on the Upsilon(1S) polarization in p p macro collisions at square root of s = 1.8 TeV using a sample of 77+/-3 pb(-1) collected by the collider detector at Fermilab. The three resonances were reconstructed through the decay Upsilon-->mu(+)mu(-). The measured angular distribution of the muons in the Upsilon(1S) rest frame is consistent with unpolarized meson production.

Diffractive dijet production at sqrt[s] = 630 and 1800 GeV at the Fermilab Tevatron

We report a measurement of the diffractive structure function F(D)(jj) of the antiproton obtained from a study of dijet events produced in association with a leading antiproton in pp collisions at sqrt[s] = 630 GeV at the Fermilab Tevatron. The ratio of F(D)(jj) at sqrt[s] = 630 GeV to F(D)(jj) obtained from a similar measurement at sqrt[s] = 1800 GeV is compared with expectations from QCD factorization and other theoretical predictions. We also report a measurement of the xi ( x-Pomeron) and beta ( x of parton in Pomeron) dependence of F(D)(jj) at sqrt[s] = 1800 GeV. In the region 0.035<xi<0.095, /t/<1 GeV2, and beta<0.5, F(D)(jj)(beta,xi) is found to be of the form beta(-1.0+/-0.1)xi(-0.9+/-0.1), which obeys beta-xi factorization.

Combined bronchoalveolar lavage and polymerase chain reaction in the diagnosis of pulmonary tuberculosis in smear-negative patients

SETTING

The polymerase chain reaction (PCR) may be sensitive and specific for the diagnosis of tuberculosis, but most reports are of studies conducted in well-controlled laboratories. A study to evaluate the clinical value of bronchoalveolar lavage (BAL) combined with PCR was necessary.

OBJECTIVE

One hundred and thirty one patients were recruited into the study from March 1994 to February 1997.

DESIGN

Patients with a positive acid-fast stain on sputum smear were recruited into group A as positive controls, patients with lung cancer and a negative acid-fast stain on sputum smear were put into group B as negative controls, and patients who had clinical symptoms of pulmonary TB without sputum or with negative smear results were the investigating group. PCR was performed on the sputum samples from group A and B patients and on the BAL fluid from those in group C.

RESULTS

The sensitivity of PCR was 96% in group A, and the specificity was 100% in group B. The sensitivity of PCR in the BAL fluid from the group C patients was 36% and the specificity was 96%; the positive predictive value was 94% and the negative predictive value was 45%.

CONCLUSION

BAL plus PCR is useful in the rapid diagnosis of pulmonary TB in non-productive or smear-negative patients.

Search for new heavy particles in the WZ0 final state in pp collisions at square root[s] = 1.8 TeV

We present the first general search for new heavy particles, X, which decay via X --> WZ0 --> e(nu)+jj as a function of M(X) and Gamma(X) in pp collisions at square root[s] = 1.8 TeV. No evidence is found for production of X in 110 pb(-1) of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W' --> WZ0 in an extended gauge model as a function of the width, Gamma(W'), and mixing factor between the W' and the standard model W bosons.

Study of B0 --> J/psiK(*)0pi(+)pi(-) decays with the collider detector at Fermilab

We report a study of the decays B0 --> J/psiK(*)0pi(+)pi(-), which involve the creation of a uu or dd quark pair in addition to a b -->c(cs) decay. The data sample consists of 110 pb(-1) of pp collisions at square root[s] = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We measure the branching fractions to be B(B0 --> J/psiK(*0)pi(+)pi(-)) = (6.6 +/- 1.9 +/- 1.1)x10(-4) and B(B0 --> J/psiK0pi(+)pi(-)) = (10.3 +/- 3.3 +/- 1.5)x10(-4). Evidence is seen for contributions from psi(2S)K(*)0, J/psiK0rho(0), J/psiK(*+)pi(-), and J/psiK1(1270).

Search for gluinos and scalar quarks in pp collisions at square root[s] = 1.8 TeV using the missing energy plus multijets signature

We have performed a search for gluinos (g) and scalar quarks (q) in a data sample of 84 pb(-1) of pp collisions at square root[s] = 1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and three or more jets, a characteristic signature in R-parity-conserving supersymmetric models. The analysis has been performed "blind," in that the inspection of the signal region is made only after the predictions from standard model backgrounds have been calculated. Comparing the data with predictions of constrained supersymmetric models, we exclude gluino masses below 195 GeV/c2 (95% C.L.), independent of the squark mass. For the case m(q) approximately m(g), gluino masses below 300 GeV/c2 are excluded.

Measurement of the strong coupling constant from inclusive jet production at the Tevatron pp collider

We report a measurement of the strong coupling constant, alpha(s)(MZ), extracted from inclusive jet production in pp collisions at square root[s] = 1800 GeV. The QCD prediction for the evolution of alpha(s) with jet transverse energy ET is tested over the range 40<ET<450 GeV using ET for the renormalization scale. The data show good agreement with QCD in the region below 250 GeV. The value of alpha(s) at the mass of the Z0 boson averaged over the range 40<ET<250 GeV is found to be alpha(s)(MZ) = 0.1178+/-0.0001(stat)+0.0081(-0.0095)(expt. syst). The associated theoretical uncertainties are mainly due to the choice of renormalization scale ((+6%)(-4%)) and input parton distribution functions (5%).

Search for gluinos and squarks using like-sign dileptons in pp macro collisions at square root of s = 1.8 TeV

We present results of the first search for like-sign dilepton ( e(+/-)e(+/-), e(+/-)mu(+/-), mu(+/-)mu(+/-)) events associated with multijets and large missing energy using 106 pb(-1) of data in pp macro collisions at square root of s = 1.8 TeV collected during 1992-1995 by the CDF experiment. Finding no events that pass our selection, we examine pair production of gluinos (tilde g) and squarks (tilde q) in a constrained framework of the minimal supersymmetric standard model. At tan beta = 2 and mu = -800 GeV/c(2), we set 95% confidence level limits of M(tilde g)>221 GeV/c(2) for M(tilde g) approximately M(tilde q), and M(tilde q)>168 GeV/c(2) for M(tilde q)>>M(tilde g), both with small variation as a function of mu.

Comparison of different protein immobilization methods on quartz crystal microbalance surface in flow injection immunoassay

In this study, a quartz crystal microbalance (QCM) system operated repetitively in flow injection analysis (FIA) mode, is reported. Four immobilization approaches of seven different methods include: (i) physical adsorption; (ii) two thioamine thiolation methods, using cysteamine and cystamine for gold chemisorption and further coupling; (iii) two oxidized dextran spacer methods, coupling of cysteamine and cystamine thiolated QCM surface with periodate-oxidized dextran for further Schiff acid-base reaction; and (iv) two thiol-gold chemisorption-based self-assembled monolayer (SAM), applying short-chain, C(3), and long-chain, C(11), mercapto fatty acids to insolubilize human serum albumin (HSA) on QCM surface. Effects of these protein immobilization methods on FIA immunoassay of anti-HSA were compared. At the 0.01 mg/ml anti-HSA level, the lowest analyte concentration tested, the SAM using 11-mercaptoundecanoic acid as QCM surface activating agent generated a larger frequency shift than the other immobilization methods. This implied that the use of thiolated long-chain fatty acid constructed as self-assembled monolayer may thereby potentially be a useful protein immobilization method in QCM-FIA application.

Observation of diffractive J/psi production at the Fermilab Tevatron

We report the first observation of diffractive J/psi(--> mu+mu-) production in pp collisions at root square[s] = 1.8 TeV. Diffractive events are identified by their rapidity gap signature. In a sample of events with two muons of transverse momentum p(mu)T>2 GeV/c within the pseudorapidity region /eta/ < 1.0, the ratio of diffractive to total J/psi production rates is found to be R(J/psi) = [1.45 +/- 0.25]%. The ratio R(J/psi)(x) is presented as a function of x-Bjorken. By combining it with our previously measured corresponding ratio R(jj)(x) for diffractive dijet production, we extract a value of 0.59 +/- 0.15 for the gluon fraction of the diffractive structure function of the proton.

Search for quark-lepton compositeness and a heavy W' Boson using the enu channel in p p macro collisions at square root of [s] = 1.8 TeV

We present searches for quark-lepton compositeness and a heavy W' boson at high electron-neutrino transverse mass. We use approximately 110 pb(-1) of data collected in p p macro collisions at square root of [s] = 1.8 TeV by the CDF Collaboration during 1992-1995. The data are consistent with standard model expectations. Limits are set on the quark-lepton compositeness scale Lambda, the ratio of partial cross sections sigma(W'-->enu)/sigma(W-->enu), and the mass of a W' boson with standard model couplings. We exclude Lambda<2.81 TeV and a W' boson with mass below 754 GeV/c(2) at the 95% confidence level. Combining with our previously published limit obtained using the muon channel, we exclude a W' boson with mass below 786 GeV/c(2) at the 95% confidence level.

Charged-particle multiplicity pp collisions at square root of (s) = 1.8 TeV

We report on a measurement of the mean charged-particle multiplicity of jets in dijet events with dijet masses in the range 80-630 GeV/c(2), produced at the Tevatron in pp collisions with square root (s) = 1.8 TeV and recorded by the Collider Detector at Fermilab. The data are fit to perturbative-QCD calculations carried out in the framework of the modified leading log approximation and the hypothesis of local parton-hadron duality. The fit yields values for two parameters in that framework: the ratio of parton multiplicities in gluon and quark jets, r identical withN(g-jet)(partons)/N(q-jet)(partons) = 1.7+/-0.3, and the ratio of the number of charged hadrons to the number of partons in a jet, K(charged)(LPHD) identical with N(charged)(hadrons)/N(partons) = 0.57+/-0.11.

Three-dimensional mapping of brain neuropils in the cockroach, Diploptera punctata

Herein, we present a complete three-dimensional (3D) map of major neuropil structures in the central brain of the cockroach Diploptera punctata. The positions of the structures have been ascertained by confocal microscopy, which, until now-for reasons of tissue opacity and nonhomogeneity-has been thought impractical in imaging fluorescently labeled structures thicker than 150 microm. In this report, however, we have used digestive enzymes and microwave-aided fixation to stain, clear, and optically section, in its entirety, an intact central brain more than 500 microm thick. The central brain from an adult female cockroach was stained thoroughly with the membrane probe NBD-ceramide and the DNA probe propidium iodide. The central brain as well as such neuropil regions as mushroom bodies, central complex, antennal glomeruli, and lobus glomerulati were individually outlined, segmented, and reconstructed in three dimensions to a spatial resolution of approximately 1 microm in the X-Y plane and 3 microm in the Z plane. The volume and surface area of each neuropil compartment were determined, and Kenyon cells of the mushroom bodies were counted. We determined that each brain hemisphere contains about 230,000 Kenyon cells, 99 antennal lobe glomeruli, and 40 lobus glomerulatus glomeruli. Segmented compartments were assigned as separate channels and merged into a single data base to reconstruct a 3D central brain containing eight different channels. This is the first 3D map at submicron resolution of an entire animal's brain that measures more than 500 microm in thickness.

Inappropriate use of antibiotics and the risk for delayed admission and masked diagnosis of infectious diseases: a lesson from Taiwan

BACKGROUND

Antibiotic resistance is a serious problem worldwide. It is particularly alarming in Taiwan and other countries of the Pacific Rim, where antimicrobial drugs are used excessively.

OBJECTIVE

To determine whether use of antimicrobial drugs before coming to an emergency department was associated with delayed admission or masked or missed diagnoses at a large general hospital in Taiwan.

METHODS

Antimicrobial activity in urine (AAU) was determined in all patients seen in the emergency department during a 3-month study. A physician, unaware of the results of the urine tests, reviewed the medical charts of patients who were admitted to the hospital to determine whether admission was delayed for at least 7 days or the diagnosis was masked or missed.

RESULTS

Of the 1182 patients, 444 were admitted to the hospital. In 220 patients (49.5%), AAU was detected. There was no significant difference in AAU between patients with or without an infectious disease (53.0% vs 46.3%, respectively; P =.41). For patients with infection, 34.8% of those with AAU had a delayed admission, compared with only 21.6% without AAU (relative risk [RR], 1.61; 95% confidence interval [CI], 1.03-2.52; P =.03). For patients without infection, 36.2% of those with AAU had a delayed admission compared with 31.1% without AAU (RR, 1.16; 95% CI, 0.81-1.68; P =.64). For patients with infection, 48.7% of those with AAU had a masked or missed diagnosis, compared with 25.5% without AAU (RR, 1.91; 95% CI, 1.30-2.80; P<.001). For patients without infection, 27.6% of those with AAU had a masked or missed diagnosis compared with 14.8% without AAU (RR, 1.87; 95% CI, 1.11-3.17; P =.02).

CONCLUSION

Use of antimicrobial drugs before coming to an emergency department was associated with a significantly increased risk for delayed and masked or missed diagnoses of infectious diseases and missed diagnosis of noninfectious diseases.

Double diffraction dissociation at the Fermilab Tevatron collider

We present results from a measurement of double diffraction dissociation in pp collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap of width Deltaeta(0)>3 (overlapping eta = 0) is found to be 4.43+/-0.02(stat)+/-1.18(syst) mb [ 3.42+/-0.01(stat)+/-1.09(syst) mb] at square root of (s) = 1800[630] GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.

Pneumocystis carinii pneumonia in systemic lupus erythematosus: a report of two cases

Patients with systemic lupus erythematosus (SLE) have increased susceptibility to infection by Pneumocystis carinii, but this condition has rarely been reported in Taiwan. Here, we describe two cases of patients with SLE who developed Pneumocystis carinii pneumonia (PCP). The first patient was a 39-year-old woman presenting with fever and dyspnea that had lasted 2 weeks. Chest roentgenography disclosed bilateral interstitial and alveolar infiltrates. The second patient was a 22-year-old woman presenting with a 4-day history of malaise, cough, dyspnea, and fever. She had concomitant Mycobacterium tuberculosis infection. Both patients had been treated with varying doses of corticosteroids and/or cytotoxic drugs within 4 months before presentation. Diagnosis was established based on the findings of bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB). Both patients received trimethoprim-sulfamethoxazole (20 mg.kg-1.d-1 trimethoprim), but finally died of nosocomial septicemia (Acinetobacter baumanni and Pseudomonas aeruginosa bacteremia in one, P. aeruginosa bacteremia in the other). These two cases demonstrate that PCP should be included in the differential diagnosis of patients with SLE presenting with pneumonic processes. In addition, a second opportunistic pathogen should be suspected. Bronchoscopic examination should be performed if the diagnosis is not clear and should include TBLB and BAL.

Implementation of clinical guidelines through an electronic medical record: physician usage, satisfaction and assessment

CONTEXT

We developed and evaluated the Emergency Department Expert Charting System (EDECS) to provide real-time guidance regarding the care of low back pain in adults, fever in children, and occupational exposure to blood and body fluids in health care workers, by embedding clinical guidelines within an electronic medical record.

OBJECTIVE

To describe the behaviors and attitudes of physicians who used EDECS.

DESIGN

Pre-post questionnaires were used to assess physician attitudes. Time studies of the intervention phase were observational, using clocks embedded in the software.

PARTICIPANTS

One hundred and forty two residents and interns in emergency, pediatric, internal, and family medicine and patients with the above-mentioned complaints.

MAIN OUTCOME MEASURES

Physician utilization of EDECS, time spent using EDECS, physician satisfaction and beliefs.

RESULTS

Eighty four percent of the 142 eligible physicians used EDECS at least once. Five hundred and ninety one of 789 (75%) eligible cases were completed using EDECS. Median session time decreased from 12 min for session 1, to 5.5 min for sessions 16 and above. Physicians generally agreed that care with EDECS was better than standard care, particularly with respect to documentation. There was, however, considerable heterogeneity in belief among complaints.

CONCLUSIONS

These data illuminate both the potentials of computer-assisted decision making and the need for context-specific approaches when attempting to implement guidelines.