Transferring the C-terminus of the chemokine CCL21 to CCL19 confers enhanced heparin binding.

Chemokines direct the migration of cells during various immune processes and are involved in many disease states. For example, CCL19 and CCL21, through activation of the CCR7 receptor, recruit dendritic cells and naïve T-cells to the secondary lymphoid organs aiding in balancing immune response and tolerance. However, CCL19 and CCL21 can also direct the metastasis of CCR7 expressing cancers. Chemokine binding to glycosaminoglycans, such as heparin, is as important to chemokine function as receptor activation. CCL21 is unique in that it contains an extended C-terminus not found in other chemokines like CCL19. Deletion of this extended C-terminus reduces CCL21's affinity for heparin and transferring the CCL21 C-terminus to CCL19 enhances heparin binding mainly through non-specific, electrostatic interactions.

Search for the rare decays K(L)→π0π0µ+µ- and K(L)→π0π0X0→π0π0µ+µ-.

The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)µ(+)µ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)µ(+)µ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)→π(0)π(0)X(0)→π(0)π(0)µ(+)µ(-)) < 1.0 × 10(-10) and Br(K(L)→π(0)π(0)µ(+)µ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.

Search for lepton-flavor-violating decays of the neutral kaon.

The Fermilab KTeV experiment has searched for lepton-flavor-violating decays of the K(L) meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their branching ratios at the 90% C.L.: BR(K(L) --> pi(0) micro(+/-) e(-/+)) <7.6 x 10(-11); BR(K(L) --> pi(0)pi(0) micro(+/-) e(-/+)) <1.7 x 10(-10); BR(pi(0) --> micro(+/-) e(-/+)) <3.6 x 10(-10). This result represents a factor of 82 improvement in the branching ratio limit for K(L) --> pi(0) micro(+/-) e(-/+) and is the first reported limit for K(L) --> pi(0)pi(0) micro(+/-) e(-/+).

Determination of the parity of the neutral pion via its four-electron decay.

We present a new determination of the parity of the neutral pion via the double Dalitz decay pi0-->e+e-e+e-. Our sample, which consists of 30,511 candidate decays, was collected from KL-->pi0pi0pi0 decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative pi0 parity and place a limit on scalar contributions to the pi0-->e+e-e+e- decay amplitude of less than 3.3% assuming CPT conservation. The pi0gamma*gamma* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase-space distribution. Additionally, we have measured the branching ratio of this mode to be B(pi0-->e+e-e+e-)=(3.26+/-0.18)x10(-5).

Measurements of the decay KL-->e+ e- gamma.

The E799-II (KTeV) experiment at Fermilab has collected 83 262 K(L)-->e+ e- gamma(gamma) events above a background of 79 events. We measure a decay width, normalized to the K(L)-->pi0pi0pi(D)0 (pi0-->gammagamma, pi0-->gammagamma, pi(D0-->e+ e- gamma(gamma)) decay width, of Gamma(K(L)-->e+e-gamma(gamma))/Gamma(K(L)-->pi0pi0pi(D)0)=(1.3302+/-0.0046(stat)+/-0.0102(syst)) x 10(-3). We also measure parameters of two K(L)gamma*gamma form factor models. In the Bergström-Massó-Singer parametrization, we find Calpha(K*)= -0.517 +/- 0.030(stat) +/- 0.022(syst). We separately fit for the first parameter of the D'Ambrosio-Isidori-Portolés model and find alpha(DIP)= -1.729 +/- 0.043(stat) +/- 0.028(syst).

First observation of K{L}-->pi{+/-}e{-/+}nue{+}e{-}.

This Letter is the first report of the K{L}-->pi{+/-}e{-/+}nue{+}e{-} decay. Based on 19 208+/-144 events, we determine the branching fraction, B(K{L}-->pi{+/-}e{-/+}nue{+}e{-}M_{e{+}e{-}}>5 MeV/c{2},E{e{+}e{-}}{*}>30 MeV)=(1.285+/-0.041)x10{-5}, and Gamma(K{e3ee}M{e{+}e{-}}>5 MeV/c{2})/Gamma(K{e3})=[4.57+/-0.04(stat)+/-0.14(syst)]x10{-5}. This ratio agrees with a theoretical prediction based on chiral perturbation theory (ChPT) calculated to O(p{4}). The measured kinematical distributions agree with those predicted by just ChPT O(p{4}), but show significant disagreement with ones predicted by leading-order ChPT.

Measurement of the K0 charge radius and a CP-violating asymmetry and a search for CP-violating E1 direct photon emission in the rare decay KL--> pi+ pi- e+ e-.

Using the complete KTeV data set of 5,241 candidate K(L)--> pi(+) pi(-) e(+) e(-) decays (including an estimated background of 204 +/- 14 events), we have measured the coupling g(CR)= 0.163 +/- 0.0149(stat) +/- 0.023(syst) of the CP conserving charge radius process and from it determined a K(0) charge radius of = [-0.077 +/- 0.007(stat) +/- 0.011(syst)]fm(2). We have determined a first experimental upper limit of 0.04 (90% C.L.) /g(e1)/ / /g(M1)/ of the couplings for the E1 and M1 direct photon emission processes. We also report the measurement of /g(M1)/ including a vector form factor /g(M1)/(1 + (a(1)/a(2))/((M(2)(p)-(M(2)(k))= 2M(K)E(gamma*)), where vector /g(M1)/= 1.11+/- 0.12(stat) +/- 0.08(syst) and a(1)/a(2) = [-0.744 +/- 0.027(stat) +/- 0.032(syst)] GeV(2)/c(2). Finally, a CP-violating asymmetry of [13.6 +/- 1.4(stat) +/- 1.5(syst)]% in the CP and T odd angle phi between the decay planes of the e(+) e(-) and pi(+) pi(-) pairs in the K(L) center of mass is reported.

Observation of the decay xi0 --> sigma+ mu- nu(mu).

The xi0 muon semileptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the xi0 beta decay mode and yields a value for the ratio of decay rates gamma(xi0 --> sigma+ mu- nu(mu))/gamma(xi0 --> sigma+ e- nu(e)) of [1.8(-0.5)(+0.7)(stat) +/- 0.2(syst)] x 10(-2). This is in agreement with the SU(3) flavor symmetric quark model.

A determination of the Cabibbo-Kobayashi-Maskawa parameter |V us| using KL decays.

We present a determination of the Cabibbo-Kobayashi-Maskawa parameter |V(us)| based on new measurements of the six largest K(L) branching fractions and semileptonic form factors by the KTeV (E832) experiment at Fermilab. We find |V(us)|=0.2252+/-0.0008(KTeV)+/-0.0021(ext), where the errors are from KTeV measurements and from external sources. We also use the measured branching fractions to determine the CP violation parameter |eta(+-)|=(2.228+/-0.005(KTeV)+/-0.009(ext))x10(-3).

Measurements of the Decay KL-->e+ e- mu+ mu-.

The KTeV experiment at Fermilab has isolated a total of 132 events from the rare decay K(L)-->e+ e- mu+ mu-, with an estimated background of 0.8 events. The branching ratio of this mode is determined to be [2.69+/-0.24(stat)+/-0.12(syst)]x10(-9), with a radiative cutoff of M(2)(ee mu mu)/M(2)(K)>0.95. The first measurement using this mode of the parameter alpha from the D'Ambrosio-Isidori-Portolès (DIP) model of the K(L)gamma*gamma* vertex yields a result of -1.59+/-0.37, consistent with values obtained from other decay modes. Because of the limited statistics, no sensitivity is found to the DIP parameter beta. We use this decay mode to set limits on CP and lepton violation.

Community-acquired pneumonia in Christchurch and Waikato 1999-2000: microbiology and epidemiology.

AIMS: To prospectively record current epidemiology and microbiology of community-acquired pneumonia in two New Zealand centres. METHODS: Between July 1999 and 2000 all adults admitted to Christchurch and Waikato Hospitals with community-acquired pneumonia were screened for study inclusion. All those enrolled had their medical history, clinical variables, inpatient management and clinical outcomes recorded and standardised microbial diagnostic testing carried out. RESULTS: 474 participants were enrolled with a mean age of 64 years and a microbial diagnosis was made in 197 cases (42%). Streptococcus pneumoniae (14%), Haemophilus influenzae (10%) and Influenza A virus (7%), Legionella spp (4%) and Mycoplasma pneumoniae (3%) were the most commonly isolated organisms. An 'atypical' organism was diagnosed in 8% of cases compared to 30% and 23% in previous Christchurch and Waikato studies respectively. Fourteen of the 67 S pneumoniae isolates (21%) had reduced susceptibility to penicillin, all with a MIC < or = 2 microg/mL, a level of reduced susceptibility not associated with worse patient outcomes. Clinical outcome included a mean hospital stay of 6.7 days and a 6 week mortality of 6%. CONCLUSION: Although S pneumoniae was the most commonly isolated organism in this study there have been significant changes in the prevalence of atypical organisms since previous surveys. Ongoing surveillance of antibiotic resistance and variations in the prevalence of organisms causing community-acquired pneumonia is required to guide clinicians' empiric antibiotic use.

A prospective evaluation of the electrocardiographic manifestations of hypothermia.

OBJECTIVE: To determine the effects of body temperature, ethanol use, electrolyte status, and acid-base status on the electrocardiograms (ECGs) of hypothermic patients. METHODS: Prospective, two-year, observational study of patients presenting to an urban ED with temperature < or =95 degrees F (< or =35 degrees C). All patients had at least one ECG obtained. Electrocardiograms were interpreted by a cardiologist blinded to the patient's temperature. J-point elevations known as Osborn waves were defined as present if they were at least 1 mm in height in two consecutive complexes. RESULTS: 100 ECGs were obtained in 43 patients. Presenting temperatures ranged between 74 degrees F and 95 degrees F (23.3 degrees C-35 degrees C). Initial rhythms included normal sinus (n = 34), atrial fibrillation (n = 8), and junctional (n = 1). Osborn waves were present in 37 of 43 initial ECGs. Of the six initial ECGs that did not have Osborn waves present, all were obtained in patients whose temperatures were > or =90 degrees F > or =32.2 degrees C). For the entire group, the Osborn wave was significantly larger as temperature decreased (p = 0.0001, r = -0.441). The correlation between temperature and size of the Osborn wave was strongest in six patients with four or more ECGs (range r = -0.644 to r = -0.956, p = 0.001). No correlation could be demonstrated between the height of the Osborn waves and the serum electrolytes, including sodium, chloride, potassium, bicarbonate, BUN, creatinine, glucose, anion gap, and blood ethanol levels. CONCLUSIONS: The presence and size of the Osborn waves in hypothermic patients appear to be a function of temperature. The magnitude of the Osborn waves is inversely correlated with the temperature.

Antimicrobial activity of merocyanine 540: a photosensitizing dye.

The antimicrobial activity of merocyanine 540 (MC 540), a photosensitizing dye previously used to purge malignant cells from autologous bone marrow grafts, was evaluated against a panel of Gram-positive and Gram-negative bacteria and Candida albicans in the presence and absence of light. In the absence of light, MC 540 demonstrated no antibacterial activity against any of the organisms tested. When combined with increasing intervals of photoillumination, growth inhibition was observed with all Gram-positive organisms tested except Mycobacterium fortuitum. Photosensitizing growth inhibition was also observed with Moraxella catarrhalis but not with any other Gram-negative bacilli including members of the Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophila, or Burkhoderia cepacia. These results suggested that differences in cell wall structure confer resistance to the photodamaging effects of the dye. MC 540 exhibited no antimicrobial activity against C. albicans in the presence or absence of light.