Association of admission hematocrit with 6-month and 1-year mortality in intensive care unit patients.

Background: This study examined the association of hematocrit (Hct) levels measured upon intensive care unit (ICU) admission and red blood cell transfusions to long-term (1-year or 180-day) mortality for both surgical and medical patients.

Study Design And Methods: Administrative and laboratory data were collected retrospectively on 2393 consecutive medical and surgical male patients admitted to the ICU between 2003 and 2009. We stratified patients based on their median Hct level during the first 24 hours of their ICU stay (Hct < 25.

Cerebral injury after cardiac surgery: identification of a group at extraordinary risk. Multicenter Study of Perioperative Ischemia Research Group (McSPI) and the Ischemia Research Education Foundation (IREF) Investigators.

Background And Purpose: Cerebral injury after cardiac surgery is now recognized as a serious and costly healthcare problem mandating immediate attention. To effect solution, those subgroups of patients at greatest risk must be identified, thereby allowing efficient implementation of new clinical strategies. No such subgroup has been identified; however, patients undergoing intracardiac surgery are thought to be at high risk, but comprehensive data regarding specific risk, impact on cost, and discharge disposition are not available.

Influence of packaging and processing conditions on the decontamination of laboratory biomedical waste by steam sterilization.

The conditions for optimal steam decontamination of polypropylene bags half loaded with laboratory biomedical waste were studied (276 bags were processed). Controls were single-closed bags without water added or incisions made in the top, standing freely in an autoclave set at 121 degrees C. The average time required to reach 121 degrees C at the load center was 46 min for controls.

Comparison of the fluorescent treponemal antibody absorption (FTA-ABS) test with the FTA-ABS double staining test for detection of antitreponemal immunoglobulin M in the 19S fraction of human serum.

A widely used immunoglobulin M (IgM) detection assay for the diagnosis of neonatal congenital syphilis is the fluorescent treponemal antibody absorption test used with fractionated serum (FTA-ABS 19S IgM test). Reading the results of the FTA-ABS test is more cumbersome than reading those of the FTA-ABS double staining (FTA-ABS-DS) test, a confirmatory test for specific IgG. To verify that the FTA-ABS-DS test used with an anti-human IgM conjugate could detect specific IgM in fractionated serum samples (FTA-ABS-DS 19S IgM test), 164 fractionated (QUIK-SEP IgM Isolation System; ISOLAB, Inc.

Specificity of the microimmunofluorescence assay for the serodiagnosis of Chlamydia pneumoniae infections.

Chlamydia pneumoniae infections are mostly confirmed using an indirect microimmunofluorescence test for which potential cross-reactions between antigens from different chlamydial species are not well documented. Using this assay, 928 sera (507 subjects) submitted for Chlamydia pneumoniae serology were tested for specific IgM and IgG to this bacteria using the TW-183 antigen. IgM and IgG reactivities to Chlamydia trachomatis serotypes C, D, E, and L2 and Chlamydia psittaci strain 6BC antigens were also tested.

Secondary immune response in a vaccinated population during a large measles epidemic.

The rates of secondary immune response (SIR) and secondary vaccine failure (SVF) during a measles epidemic (10,184 notifications) were evaluated. A patient with SIR was defined as a subject for whom all sera were immunoglobulin G (IgG) positive and IgM negative with a significant increase in complement fixation titer. A patient with SVF was defined as a vaccinated symptomatic subject showing a SIR.

Performance and reliability of the Enzygnost measles enzyme-linked immuno-sorbent assay for detection of measles virus-specific immunoglobulin M antibody during a large measles epidemic.

Evaluation of the Enzygnost Measles Enzyme-Linked Immuno-Sorbent Assay kit (Behring) performance to detect specific immunoglobulin M (IgM) was carried out with 3,297 single serum samples and 898 paired serum samples collected during a measles epidemic (10,184 reported cases) in Quebec, Canada. Anti-measles IgM and IgG were detected by using the Enzygnost kit with the appropriate conjugates. Complement-fixing (CF) antibody (Ab) titers were assessed by the laboratory branch complement fixation micromethod.

DNA polymorphism among isolates from multiple sites of a patient with chronic herpes simplex virus, type 1 infection.

DNA polymorphisms among independent isolates of herpes simplex virus (HSV) type 1 were studied from a 7-year-old male patient with recurrent infections of the skin and internal organs. In the patient's serum, HSV antibodies could not be detected by complement fixation, enzyme-linked immunosorbent assay (ELISA), or neutralization tests. ELISA tests for the presence of antibodies to human immunodeficiency virus were also negative.

Immunofluorescence assay for human immunodeficiency virus antibody: investigation of cell fixation for virus inactivation and antigen preservation.

Four cell fixation procedures were investigated for their abilities to inactivate human immunodeficiency virus (HIV) and preserve its antigenicity for antibody detection by immunofluorescence in MOLT-4-T4 cells. Air-dried cell smears were fixed in cold acetone, in acetone-methanol (1:1), in acetone-methanol (1:1) followed by 70% ethanol and then methanol, or in paraformaldehyde-acetone. Acetone alone did not inactivate cell-associated HIV, but the other three procedures did.

Intrathecal morphine reduces the minimum alveolar concentration of halothane in humans.

The authors hypothesized that the analgesia provided by intraspinal opiates would decrease anesthetic requirement. To test this hypothesis, 20 women undergoing major gynecologic surgery were divided randomly into two groups. One group received 0.

Performance and reliability of five commercial enzyme-linked immunosorbent assay kits in screening for anti-human immunodeficiency virus antibody in high-risk subjects.

Anti-human immunodeficiency virus enzyme-linked immunosorbent assay kits marketed by Electro-Nucleonics Inc. (ENI), Genetic Systems Corp. (GSC), Organon Teknika Inc.

Computerized analysis of antimicrobial drugs interactions in biological systems using an IBM-PC microcomputer.

We have developed a computer program to analyse the individual and combined effects of two treatments applied concurrently to a biological system. Analysis is done in regard to: level of significance selected for the statistical test (two-sided Student's t test); number of data available; expected combined effect resulting from addition (computed by the program); experimental hypothesis tested (synergism or antagonism). The main program gives access to eight options: input of new data; input of data from file; addition or modification to data in memory; display on monitor the results from analysis or the contents of a data file; analysis with another level of significance; printout; kinetics of interaction; end of program.

Elimination of plasmidic resistance to ampicillin and of enterotoxinogenicity in certain enteric gram-negative bacteria after incubation with high concentrations of amprolium.

We have observed that treatment with high concentrations of a thiamine analog (amprolium) can lead to the elimination of the plasmidic resistance to ampicillin and the production of enterotoxin in wild Escherichia coli strains and in E coli and Salmonella typhimurium strains which had received the pKM101 plasmid through bacterial conjugation. By computer analysis, we also have determined that there is a highly significant (P less than 0.01) synergism between ampicillin and amprolium which reduces considerably the growth of certain enteric bacterial strains which have a plasmidic resistance to ampicillin and which were not markedly affected by amprolium alone, in our experimental conditions.

Estimation of endpoints in biological systems.

A program, written in BASIC, has been developed to estimate rapidly endpoints from a small number of experimental data. The computational method is based on the work of Reed and Muench (Am. J.

Analysis of interactions between treatments applied concurrently onto biological systems.

A program, written in BASIC, has been developed to analyse results of experiments studying individual and combined effect of two treatments (physical or chemical) on a biological system. Analysis is done in regard to: (1) level of significance selected for statistical test; (2) number of data available; (3) expected combined effect of treatments resulting from addition which is computed using an original formula; (4) experimental hypothesis tested. Using this program we have determined that there is a highly significant synergism between ampicillin (antibiotic) and amprolium (antiparasitic drug) to reduce the growth of some enteric bacterial strains which have a plasmidic resistance to ampicillin.

Pulmonary, chest wall, and lung-thorax elastances in acute respiratory failure.

The usefulness of lung-thorax compliance (or elastance) as an index of pulmonary compliance (or elastance) was examined in 15 patients being ventilated for acute respiratory failure. Mean lung-thorax elastance (ELT) was 27.9 +/- 2.

Multipatient anesthetic mass spectrometry: rapid analysis of data stored in long catheters.

A centrally located mass spectrometer sequentially samples airway gases from ten anesthetized patients through 30 m long, 1.07 mm, ID, nylon catheters and three way solenoid valves. End-tidal and inspired concentrations of O2, N2, CO2, N2O, and halothane, enflurane, or isoflurane are displayed on a computer terminal screen in each OR with trend plots.

[Inapparent persistent chlamydial infection in McCoy cells].

We have studied the phenomena of inapparent chlamydial infections in vitro using McCoy cells in culture as hosts and low doses of Chlamydia psittaci (GP-IC) as infecting agents. The results indicate that GP-IC can persist undetected at least 220 hrs in McCoy cells previously inoculated with 0.2 mL of a GP-IC preparation containing 30 ifu/mL, using the centrifuge-assisted inoculation technique.

Measurement of functional residual capacity during mechanical ventilation by simultaneous exchange of two insoluble gases.

A precise method for rapid measurement of functional residual capacity (FRC) during mechanical ventilation that uses the simultaneous exchange of argon and nitrogen is described. Circuit leaks were immediately recognizable upon completion of a run, and pneumotachygraphic inaccuracies due to turbulent flows, changes in viscosity, and time delays between pneumotachygraph and mass spectrometer signals were avoided. For 166 duplicate determinations, the first measurement of FRC differed from the second by 0.

Time course and mechanisms of lung-volume increase with PEEP in acute pulmonary failure.

To determine the effects of a step change in end-expiratory pressure on functional residual capacity (FRC) and lung-thorax compliance (CLT), 10 cm H2O positive end-expiratory pressure (PEEP) was applied in eight patients who needed mechanical ventilation for acute pulmonary failure. Of the total change in FRC, 66 +/- 5.3 per cent (mean +/- SEM) was complete within the next breath, and 90 per cent change was achieved in 4.

Inapparent chlamydial infection in the urogenital tract of guinea-pigs.

Microbiologically inapparent urogenital infection appeared to be induced in male guinea-pigs inoculated intra-urethrally with low doses of the guinea-pig inclusion conjunctivitis strain (GP-IC) of Chlamydia psittaci. This state was indicated by the ability of inoculated animals to donate eye infection to normal animals caged with them. Donors failed to develop overt urogenital infection throughout the period of transmission judged by both absence of infected cells in urethral scrapings and failure to isolate GP-IC in cell culture; however, inoculation of donors with 5-iododeoxyuridine led to transient appearance of infectivity in scrapings.