Bacteremia associated with live attenuated chi8110 Salmonella enterica serovar Typhi ISP1820 in healthy adult volunteers

Live attenuated chi8110 Salmonella enterica serovar Typhi ISP1820 vaccine was given in a dose-escalation trial to healthy, adult volunteers. Positive stool and blood cultures were noted, but limited, as were immune responses measured by ELISA and ELISPOT. Only volunteers with bacteremia developed immune responses; however, no symptoms were associated with bacteremia. The vaccine was insufficiently immunogenic for use as a vaccine. It is possible that reduced survival in the gut and reduced immunogenicity may have been due to the thawing of frozen inocula immediately prior to use.

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.

Measurement of d sigma/dM and forward-backward charge asymmetry for high-mass Drell-Yan e(+)e(-) pairs from pp macro collisions at square root of s = 1.8 TeV

We report on a measurement of the mass dependence of the forward-backward charge asymmetry, A(FB), and production cross section d sigma/dM for e(+)e(-) pairs with mass M(ee)>40 GeV/c(2). The data sample consists of 108 pb(-1) of pp macro collisions at square root of s = 1.8 TeV taken by the Collider Detector at Fermilab during 1992-1995. The measured asymmetry and d sigma/dM are compared with the predictions of the standard model and a model with an extra Z' gauge boson.

SEM visualization of glycosylated surface molecules using lectin-coated microspheres

There are several techniques currently used to localize glycosylated surface molecules by scanning electron microscopy (Grinnell, 1980; Molday, 1976; Linthicum and Sell, 1975; Nicolson, 1974; Lo Buglio, et al, 1972). A simple and rapid method, using a modification of Grinnell's technique is reported here. Essentially, microspheres coated with Concavalin A are used to bind to glycosylated regions of the palatal shelf epithelium and are visualized in the scanning electron microscope (SEM).

Acceleration of fusion in mouse palates by in vitro exposure to excess G

Palatal shelves from 13- and 14-day mouse embryos were excised and cultured in contiguous pairs. Experimental cultures were exposed to 2.6 G in a culture centrifuge; controls were in the same incubator. After 24 hours, palates were prepared for light or electron microscopy. Scoring of paraffin sections according to the stage of fusion seen in the medial epithelial edges (MEE) showed that palates exposed to excess G were in more advanced stages of fusion than were controls. Ultrastructurally, control MEE had tightly apposed cell membranes and numerous desmosomes; in centrifuged MEE, desmosomes had been removed and there was much intercellular space. Nuclear membranes were intact in control MEE, but showed marked deterioration in MEE of centrifuged palates. Few lysosomes and no necrosis were seen in control MEE; centrifuged MEE had numerous lysosomes as well as necrotic cells. Basal lamina were intact in controls, but interrupted in centrifuged palates. The results confirm the hypothesis that gravitational increases speed up the differentiative process.

Measurement of the top quark p(T) distribution

We have measured the p(T) distribution of top quarks that are pair produced in pp collisions at sqrt[s] = 1.8 TeV using a sample of tt decays in which we observe a single high- p(T) charged lepton, a neutrino, and four or more jets. We use a likelihood technique that corrects for the experimental bias introduced due to event reconstruction and detector resolution effects. The observed distribution is consistent with the standard model prediction. We use these data to place limits on the production of high- p(T) top quarks suggested in some models of anomalous top quark pair production.

High-dose chemotherapy and hematopoietic stem cell transplantation for breast cancer: past or future?

Given that each year in the United States 180,000 new cases of breast cancer are diagnosed, with about 44,000 women succumbing to the disease, and that breast cancer is the second leading cause of cancer-related death in women, it is clear that existing therapy fails a large number of patients. Recently, a number of novel strategies have been developed in attempts to improve survival. These include agents used at very high dose requiring stem cell support. High-dose chemotherapy (HDC) with hematopoietic stem cell transplantation (HSCT), most frequently in the form of peripheral blood progenitor cell transplantation (PBPCT), is an highly active treatment approach in appropriate patients and the current data relating to this modality will be reviewed here. This article will attempt to place the recent randomized studies in perspective, to highlight the strengths and limitations of the data, and to offer some thoughts on future directions for the field.

Preparation and application of antibodies to phosphoamino acid sequences

In this review, we describe methods to generate and characterize sequence-specific phosphoamino acid antibodies. Several of the early contributions regarding the utility of such antibodies are summarized. Three antiphosphopeptide antibodies derived from sequences of the Bcr protein are described. They are anti-Bcr pSer-354, anti-Bcr pTyr-328, and anti-Bcr pTyr-360. These anti-Bcr phosphopeptide antibodies are directed toward phosphorylated sequences encoded by the first exon of the BCR gene, which is the critical portion of the Bcr sequence present in the Bcr-Abl oncoprotein. Using these antibodies, we established/confirmed the in vivo phosphorylation of Ser-354, Tyr-328, and Tyr-360 in Bcr and Bcr-Abl proteins. The cross-reactivity of these antibodies, which is a common problem with antipeptide antibodies, was also investigated and discussed.

Endovascular repair of traumatic pseudoaneurysm by uncovered self-expandable stenting with or without transstent coiling of the aneurysm cavity

Various surgical options for internal carotid or subclavian artery pseudoaneurysm repair have been reported; however, in general they have resulted in poor outcomes with high morbidity and mortality rates. Recently, these open surgical procedures have been partly replaced by percutaneous transluminal placement of endovascular devices. We evaluated the potential for using flexible self-expanding uncovered stents with or without coiling to treat extracranial internal carotid, subclavian and other peripheral artery posttraumatic pseudoaneurysm. Three patients with posttraumatic pseudoaneurysm were treated by stent deployment and coiling (two cases) of the aneurysm cavity. In one case, a 5.0 x 47 mm Wallstent (Boston Scientific) was positioned to span the neck of the 9 x 5 mm size pseudoaneurysm (left internal carotid artery) and deployed. Angiography demonstrated complete occlusion of the pseudoaneurysm without coiling. In the second patient, a 5.0 x 31 mm Wallstent (Boston Scientific) was positioned to span the neck of the 9 x 7 mm size pseudoaneurysm (right internal carotid artery) and deployed. A total of six coils (Guglielmi Detachable Coils, Boston Scientific) were deployed into the pseudoaneurysm cavity until it was completely obliterated. In the third case, an 8.0 x 80 mm SMART (Cordis) stent was advanced over the wire, positioned to span the neck of the 10 x 7 mm size pseudoaneurysm of the left subclavian artery, and deployed. Fourteen 40 x 0.5 mm Trufill (Cordis) pushable coils were deployed into the pseudoaneurysm cavity until it was completely obliterated. At long-term follow-up (6-9 months), all patients were asymptomatic without flow into the aneurysm cavity by Duplex ultrasound. We conclude that uncovered endovascular flexible self-expanding stent placement with transstent coil embolization of the pseudoaneurysm cavity is a promising new technique to treat posttraumatic pseudoaneurysm vascular disease by minimally invasive methods, while preserving the patency of the vessel and side branches.

[Clinical significance and frequency of the 11q23/MLL genetic molecular alteration in Chilean infants with acute leukemia]

BACKGROUND

Acute leukemia (AL) in infants generally shows distinctive biologic features and has a poor prognosis.

AIM

To study the frequency of the cytogenetic alteration of 11q23 chromosome or the recombination of MLL gene in infants less than 18 months old, with acute leukemia.

PATIENTS AND METHODS

We analyzed 37 cases of AL in infants less than 18 months of age diagnosed in Chile from 1989 to 1999. The clinical features and cytogenetic/molecular defects of 11q23MLL gene rearrangement and their influence in prognosis were determined.

RESULTS

There were 18 cases of acute Lymphoblastic leukemia (ALL) characterized by female sex (67%) high presenting leukocyte count (median 99 x 109/L), blast cells with a CD10 negative phenotype (50%) and 11q23/MLL rearrangement (39%). Molecular abnormalities of 11q23 were significantly associated with adverse prognosis, with an event free survival (EFS) of only 14 +/- 12%. Interestingly, infants with germ line 11q23 had a very good outcome with an EFS of 73 +/- 11% (p < 0.025). There were 19 cases of acute myeloblastic leukemia (AML) characterized by male sex (63%) high leukocyte count (median 93 x 109/L), FAB-MS morphology (53%) and 11q23/MLL rearrangement (53%). EFS was very poor, 20 +/- 9% and 33 +/- 4% for rearranged and germinal group respectively (p = NS), due to a high mortality rate during the first month of diagnosis.

CONCLUSIONS

These findings demonstrate that Chilean ALL infants with 11q23 abnormalities have a very poor prognosis. However those with germinal state can enjoy a prolonged disease free survival with the current treatment protocols.

Preparation and characterization of a set of IAEA reference air filters for quality control in air-pollution studies

Several sets of reference air filters were prepared as part of an IAEA evaluation of the performance of laboratories involved in air-pollution studies. Each set comprised three polycarbonate membrane filters, two of which were loaded with urban air particulate matter (APM) obtained in Vienna or Prague, and one unloaded filter. The filters were loaded by filtration of a suspension of the APM materials in water. The homogeneity both of bulk APM materials and of the loaded filters was evaluated and found suitable by determining several elements by instrumental neutron-activation analysis (INAA), proton-induced X-ray emission (PIXE), and micro-X-ray energy-dispersive fluorescence analysis (micro-EDXRF). After evaluation of the homogeneity, INAA, PIXE, EDXRF, atomic absorption spectrometry (AAS), inductively coupled plasma optical emission spectrometry (ICP-OES), and ICP mass spectrometry (ICP-MS) were used to characterize the filter materials and establish "target values" and their associated standard deviations for 15 elements. Problems encountered during the preparation of these unique, simulated air filters and the criteria for setting both the target values and standard deviations are presented.

Is untargeted outreach visiting in primary care effective? A pragmatic randomized controlled trial

BACKGROUND

There is increasing evidence that clinical guidelines can lead to improvements in clinical care. However, they are not self-implementing. Outreach visits may improve prescribing behaviour.

METHODS

Within a before-and-after pragmatic randomized controlled trial, involving all general practices in one health district, routine methods were used to distribute guidelines for management of Helicobacter pylori eradication. Intervention practices were offered a visit and the conduct of an audit by a pharmacist trained in the techniques of outreach visiting. The intervention was evaluated using level three Prescribing Analysis and Cost (PACT) data for metronidazole and omeprazole for the two 12 month periods around the introduction of the guidelines.

RESULTS

Of the 38 intervention practices 19 accepted an outreach visit and three accepted the offer of an audit. There was a significant increase in omeprazole use during the study of 0.24 [95 per cent confidence interval (CI) +0.19 to +0.29] dose units per year but no effect from the offer [-0.02 (95 per cent CI -0.12 to +0.08) dose units] or acceptance of a visit [-0.03 (95 per cent CI -0.15 to +0.08) dose units]. The results for metronidazole were similar, with an increase in use of 0.028 (95 per cent CI +0.018 to +0.038) dose units per year. The effect of the intervention was a non-significant change in prescribing of -0.005 (95 per cent CI -0.025 to +0.015) dose units. Accepting a visit had little effect on prescribing: a change of 0.003 (95 per cent CI -0.021 to +0.027) dose units.

CONCLUSIONS

The routine use of untargeted outreach visiting is probably not a worthwhile strategy.

A CANDESARTAN CILEXETIL/HYDROCHLOROTHIAZIDE COMBINATION TABLET PROVIDES EFFECTIVE BLOOD PRESSURE CONTROL IN HYPERTENSIVE PATIENTS INADEQUATELY CONTROLLED ON MONOTHERAPY

In this double-blind, placebo-controlled, randomised, parallel-group study, a combination tablet of candesartan cilexetil/hydrochlorothiazide (HCTZ), 16/12.5 mg once daily, reduced sitting diastolic blood pressure (DBP) significantly more (p = 0.037) than candesartan cilexetil/placebo, 16 mg once daily, in patients with mild to moderate primary hypertension (n = 328) who had not reached target blood pressure with candesartan cilexetil, 16 mg once daily. At the end of the 8-week double-blind treatment period, the adjusted mean reductions in sitting DBP, 24 h post dose, were 7.5 mm Hg in the candesartan cilexetil/HCTZ treatment group and 5.5 mm Hg in the candesartan cilexetil/placebo treatment group, corresponding to an adjusted mean difference between treatments of 2.0 mm Hg in favour of candesartan cilexetil/HCTZ (95% CI 0.1-3.8 mm Hg, p = 0.037). The adjusted mean reductions in sitting systolic blood pressure, 24 h post dose, were 12.0 mm Hg and 7.5 mm Hg, respectively, corresponding to an adjusted mean difference between treatments of 4.5 mm Hg (95% CI 1.1-8.0, p = 0.01). Consistent with the placebo-like tolerability of candesartan cilexetil reported in other studies, both treatments were very well tolerated, with a similar pattern and low frequency of adverse events in both treatment groups.

Synthesis of C-3 nitrogen-containing derivatives of N-acetyl-alpha,beta-D-mannosamine as substrates for N-acetylneuraminic acid aldolase

The synthesis of 3-azido-3-deoxy, 3-amino-3-deoxy and 3-N-tert-butyloxycarbonyl-3-deoxy derivatives of 2-acetamido-2-deoxy-alpha,beta-D-mannose (N-acetyl-alpha,beta-D-mannosamine, ManNAc), is presented. The 3-azido-3-deoxy- and 3-N-tert-butyloxycarbonyl compounds were further characterised as their peracetates. A preliminary study has found that these C-3 nitrogen-substituted derivatives of ManNAc not to be substrates for Neu5Ac aldolase.

Mitoxantrone and paclitaxel combination chemotherapy in metastatic breast cancer

This study evaluated mitoxantrone and paclitaxel combination chemotherapy in the treatment of patients with metastatic breast cancer. Thirty-seven patients who had developed progressive disease after prior chemotherapy were treated with mitoxantrone (14 mg/m2) and paclitaxel (150 mg/m2) every 21 days for a maximum of six cycles. The most frequent grade 3 or 4 nonhematological toxicities were fever and nausea. Grade 4 neutropenia occurred in 71% of patients. Cardiotoxicity occurred in 2 patients, both of whom had previously received doxorubicin. Objective response was achieved in 35% of patients (5% complete response and 30% partial response) and 41% had stable disease. Median time to disease progression and median survival were 6 and 12 months, respectively. The percent of patients with an objective response was not different for those who had received prior doxorubicin or had chemotherapy in the preceding 6 months. This regimen appears to be effective and well tolerated as salvage therapy and merits further evaluation.

A Phase 1 study of a recombinant viruslike particle vaccine against human papillomavirus type 11 in healthy adult volunteers

Viruslike particles (VLPs) produced from the L1 protein of several papillomaviruses have induced protection from infection after live challenge in animal models. In the present study, the safety and immunogenicity of a human papillomavirus (HPV)--11 L1 VLP candidate vaccine were measured in a phase 1, dose-finding trial in humans. The vaccine was well tolerated and induced high levels of both binding and neutralizing antibodies. Marked increases in lymphoproliferation to HPV--11 L1 antigens were noted after the second vaccination. In addition, lymphoproliferation was induced after vaccination in peripheral blood mononuclear cells (PBMC) stimulated with heterologous L1 VLP antigens of HPV types 6 and 16. Statistically significant increases in HPV antigen--specific interferon--gamma and interleukin-5 production were measured from PBMC culture supernatants. This candidate HPV VLP vaccine induced robust B and T cell responses, and T cell helper epitopes appear to be conserved across HPV types.

Search for neutral supersymmetric Higgs bosons in pp collisions at sqrt[s] = 1.8TeV

We present the results of a search for neutral Higgs bosons produced in association with b quarks in pp-->bb(phi)-->bbb final states with 91+/-7 pb(-1) of pp collisions at sqrt[s] = 1.8 TeV recorded by the Collider Detector at Fermilab. We find no evidence of such a signal and the data are interpreted in the context of the neutral Higgs sector of the minimal supersymmetric extension of the standard model. With basic parameter choices for the supersymmetric scale and the stop-quark mixing, we derive 95% C.L. lower mass limits for neutral Higgs bosons for tan(beta) values in excess of 35.

The safety and effectiveness of the Le Fort I approach to removing central skull base lesions

The difficulty of gaining access to the central skull base has led to the development of many surgical approaches to this area during the past decade. Yet we believe that the Le Fort I technique, which has been used for almost 140 years in orthognathic surgery, is still an excellent approach to treating anterior skull base lesions. This procedure, which entails the horizontal sectioning of the dentoalveolar maxillary segment, seemed to fall out of favor with otolaryngologists after a few reports of complications surfaced during the past 10 to 15 years. In this article, we report a series of seven patients whom we treated with a Le Fort I approach during a 3-year period for a variety of benign and malignant anterior skull base lesions. We have encountered no significant complications of surgery or recurrence of disease at a maximum postoperative followup of 3 years.

Evaluation of canarypox-induced CD8+ responses following immunization by measuring the effector population IFNγ production

CD8(+) cytolytic activity is traditionally measured by detecting the release of 51Cr after incubation of effector cells with HLA-matched, infected, radiolabeled targets. An alternative method to detect CD8+ activity is to measure the production of intracellular interferon gamma (IFNgamma) after antigen-specific stimulation, either by ELISPOT or by flow cytometry. Studies were performed in 19 volunteers enrolled in a phase 1 trial of candidate canarypox HIV-1 vaccines that encoded multiple HIV-1 genes. The vaccines including vCP205 (Env, Gag, and protease), vCP1433 (Env, Gag, protease, and CTL epitope-rich regions of pol and nef) and vCP1452 (equivalent to vCP1433 with additional immunomodulatory genes of vaccinia). PBMCs were stimulated in vitro with vaccinia constructs encoding env and gag or a lacZ control, and the effectors were cultured for 12-14 days. EBV-transformed B cell lines were infected overnight with the vaccinia vectors, and then incubated with the effector cells for 4 h in the presence of monensin. CD8(+) gene-specific activity was determined as a percentage of IFNgamma cells in the CD3(+)CD8(+)CD45RO(+) gate after subtracting both the isotype control and the lacZ control stimulation. CD4 memory IFNgamma production was simultaneously determined in the CD3(+)CD8(-)CD45RO(+) gate. Using these techniques in blinded studies, we found that CD8(+) IFNgamma activity could be measured in the majority of volunteers given four immunizations. Specifically, the responses to the gag gene were control -- 0/2; vCP205 -- 2/4; vCP1433 -- 5/6; vCP1452 -- 4/7. Most of the positive responses were detected after the fourth immunization. Flow cytometric techniques hold promise as a surrogate measure of CTL and for ease of phenotyping of the effector population.

Setting performance standards for medical practice: a theoretical framework

BACKGROUND

The assessment of performance in the real world of medical practice is now widely accepted as the goal of assessment at the postgraduate level. This is largely a validity issue, as it is recognised that tests of knowledge and in clinical simulations cannot on their own really measure how medical practitioners function in the broader health care system. However, the development of standards for performance-based assessment is not as well understood as in competency assessment, where simulations can more readily reflect narrower issues of knowledge and skills. This paper proposes a theoretical framework for the development of standards that reflect the more complex world in which experienced medical practitioners work.

METHODS

The paper reflects the combined experiences of a group of education researchers and the results of literature searches that included identifying current health system data sources that might contribute information to the measurement of standards.

CONCLUSION

Standards that reflect the complexity of medical practice may best be developed through an "expert systems" analysis of clinical conditions for which desired health care outcomes reflect the contribution of several health professionals within a complex, three-dimensional, contextual model. Examples of the model are provided, but further work is needed to test validity and measurability.

Production of chi(c1) and chi(c2) in pp collisions at sqrt[S] = 1.8 TeV

We have measured the ratio of prompt production rates of the charmonium states chi(c1) and chi(c2) in 110 pb(-1) of pp collisions at sqrt[s] = 1.8 TeV. The photon from their decay into J/psi(gamma) is reconstructed through conversion into e+e- pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections sigma(chi(c2))/sigma(chi(c1)) = 0.96+/-0.27(stat)+/-0.11(syst) for events with pT(J/psi) > 4.0 GeV/c, /eta(J/psi)/ < 0.6, and pT(gamma) > 1.0 GeV/c.

First measurement of the ratio B(t --> Wb)/B(t --> Wq) and associated limit on the Cabibbo-Kobayashi-Maskawa element /V(tb)/

We present the first measurement of the ratio of branching fractions R identical withB(t-->Wb)/B(t-->Wq) from p_p collisions at sqrt[s] = 1.8 TeV. The data set corresponds to 109 pb(-1) of data recorded by the Collider Detector at Fermilab during the 1992-95 Tevatron run. We measure R = 0.94(+0.31)(-0.24)(stat+syst) or R>0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element /V(tb)/ under the assumption of three generations and unitarity.