Randomized controlled trial of oral vs intravenous therapy for the clinically diagnosed acute uncomplicated diverticulitis.

OBJECTIVE: Despite the high prevalence of hospitalization for left iliac fossa tenderness, there is a striking lack of randomized data available to guide therapy. The authors hypothesize that an oral antibiotic and fluids are not inferior to intravenous (IV) antibiotics and 'bowel rest' in clinically diagnosed acute uncomplicated diverticulitis. METHOD: A randomized controlled trial was constructed in two District General Hospitals. All clinically diagnosed patients presenting with acute uncomplicated diverticulitis were eligible for the study. Oral and IV regimens utilizing ciprofloxacin and metronidazole were compared. The primary outcomes studied were surrogates for resolution of symptoms (including tenderness on day 3 and length of stay) and failure of oral therapy. Secondary endpoints studied were serial constitutional and biomarker trends. RESULTS: There were 41 patients in the oral arm and 38 in the IV arm (n = 79). No patient had to be converted to IV antibiotics from the oral group. There was a complete resolution of symptoms in both groups. Tenderness was equivalent in both groups on day 3. Among secondary endpoints, a serial decrease in C reactive protein was the best serological predictor of resolution for both groups. CONCLUSION: Oral antibiotics are not inferior to intravenous antibiotics in achieving resolution of clinically diagnosed diverticulitis.

Low molecular weight heparin prophylaxis in day case surgery.

BACKGROUND: The role of Low molecular weight heparins (LMWH) in day case/short-stay surgery is unknown. AIM: To characterise the current national use of LMWH prophylaxis in specific day and short stay surgeries. METHODS: A standardised anonymous postal questionnaire was sent to all consultant general surgeons in Ireland. The operations selected were herniorraphy, anorectal, varicose vein and laparoscopic cholecystectomy. RESULTS: Questionnaires were sent to 82 surgeons in 2003. There was a response rate of 68.3% (56). Fifty-four per cent of respondents said there was a protocol in place for administration of LMWH in day case surgery. Of these 41% were not confident that their protocols were being adhered. Fifty-nine per cent of all respondents said they stratified patients according to individual risk. Thirteen per cent reported occurrence of VTE post day case surgery CONCLUSION: This study demonstrates a heterogeneous pattern of administration of LMWH. In the absence of published validated protocols, the authors suggest a consensus day case protocol.

Legibility of doctor's signatures: novel approaches to improving an age-old problem.

UNLABELLED: In today's medico-legal environment, the importance of identification of the authors of notes in patient medical charts cannot be overemphasized. We evaluated three different techniques of signing patient notes, over a one month period, in order to determine which technique was the most effective in identifying the author of the note. Surgical NCHDs in our hospital were divided into three groups. Group 1 was asked to sign the notes as they normally would. Group 2 was asked to print their name in block capitals after their signature and Group 3 was given pens with a personal self inking stamp to be used in addition to signing the notes. The number of signatures in all the charts, compliance with the assigned technique and the legibility of signatures were calculated. RESULTS: in Group 1, all NCHDs signed their name when writing notes (100% compliance), however the NCHD's signature was identified only 37% of the time. In Groups 2 (who signed in block capitals) and Group 3 (who used the pen with personalised stamp) the author was identifiable 100% of the time when the respective signing method was used. Using the pen with personalised self inking stamp was significantly more popular (77% compliance) compared to signing in block capitals (46% compliance). In conclusion the pen, with personalised self inking stamp, provides a fast and effective means to clarify signatures of NCHD's documentation, which is not only important in a day to day patient management, but is essential from a medico-legal stand point.

Fate of mRNA following disaggregation of brain polysomes after administration of (+)-lysergic acid diethylamide in vivo.

Intravenous injection of (+)-lysergic acid diethylamide into young rabbits induced a transient brain-specific disaggregation of polysomes to monosomes. Investigation of the fate of mRNA revealed that brain poly(A+)mRNA was conserved. In particular, mRNA coding for brain-specific S100 protein was not degraded, nor was it released into free ribonucleoprotein particles. Following the (+)-lysergic acid diethylamide-induced disaggregation of polysomes, mRNA shifted from polysomes and accumulated on monosomes. Formation of a blocked monosome complex, which contained intact mRNA and 40-S plus 60-S ribosomal subunits but lacked nascent peptide chains, suggested that (+)-lysergic acid diethylamide inhibited brain protein synthesis at a specific stage of late initiation or early elongation.

Effectiveness and efficiency of selective vs universal screening for chlamydial infection in sexually active young women.

BACKGROUND: Since chlamydial cervicitis is not associated with specific complaints, screening asymptomatic women is an important initiative to prevent pelvic inflammatory disease and its sequelae. Compared with universal screening, selective screening is less costly but less effective so the cost savings vs the consequences of missing infected women need to be weighed carefully. METHODS: In two family planning clinics, 1002 women were surveyed for chlamydial infection (prevalence, 7%) and its predictors to determine whether universal or selective screening is the most efficient strategy. Two rules for the selection of patients were determined by logistic regression modeling and their relative efficiencies were compared by incremental cost-effectiveness and sensitivity analysis. The validity of the screening rules was tested in 191 students attending a university health clinic. RESULTS: If those with cervical friability, suspicious discharge, urinary frequency, or intermenstrual bleeding had been tested, 55.3% of all women would have been screened and 83.3% of all cases would have been detected. If those reporting a new sex partner in the preceding year had also been tested, 75.4% would have been screened, identifying 93.3% of all cases. The predictive power and practicality of the selection rules were validated in the university health clinic sample. Sensitivity analyses showed selective screening using cervical enzyme immunoassay with blocking confirmation was efficient if the prevalence of chlamydial infection was 16% or less, 11% or less, or 5% or less depending on whether base analyses, overestimated costs, or worst performance scenarios, respectively, were used. CONCLUSIONS: Selective screening based on four or five predictors and confirmed cervical enzyme immunoassay is an effective and efficient strategy in low prevalence settings.

Selective action of colchicine on protein synthesis and release in a clonal line of rat glial cells.

The effect of colchicine on protein synthesis and secretion in stationary cultures of clonal rat glial cells C6 was examined. Colchicine inhibited the synthesis of the brain specific S100 protein in intact cells but not in a cell-free protein synthesizing system derived from these cells. There was no demonstrable effect of the drug on the synthesis of any of the several hundred proteins resolved by a two-dimensional electrophoretic analysis. However, colchicine specifically enhanced the secretion of several proteins of molecular weighs of 30,000 and of 200-300,000 into the medium. Two of the high molecular weight proteins were apparently membrane proteins whose release into the medium was stimulated by the drug.

Dendritic cell discoveries provide new insight into the cellular immunobiology of DNA vaccines.

The evolution of increasingly virulent human pathogens, together with the rapid onset of antimicrobial resistance has created a need for new vaccination strategies. Nucleic acid vaccines, based on recombinant DNA technology are a promising new vaccine formulation capable of eliciting both humoral and cellular immune responses. This technology has been experimentally validated in animal models of pathogen challenge and tumor protection following administration of a DNA vaccine and has led to extensive research into the mechanisms of protective immunity. We focus here on the cellular and molecular mechanisms leading to cell-mediated immune responses to DNA vaccines and discuss these mechanisms in light of recent advances in the field of dendritic cell immunobiology. In particular, the potential involvement of: (i) the CpG pattern-recognition receptor, toll-like receptor-9; (ii) the dendritic cell-specific surface adhesion molecule, DC-SIGN; and (iii) the molecular interactions between CD40 and CD154 in the evolution of protective cell-mediated immunity to DNA vaccines are discussed. An improved understanding of the precise mechanisms leading to protective cellular immunity following DNA vaccination may help in the design of novel DNA constructs containing immunostimulatory features that target one or more of these mechanisms, with the aim of increasing the immunogenic potential and protective efficacy of DNA vaccines.

Strategic targeting of essential host-pathogen interactions in chlamydial disease.

The chlamydiae are obligate intracellular gram-negative bacteria that are exquisitely adapted for exploitation of their hosts and contribute to a wide range of acute and chronic human diseases. Acute infections treated with non-cidal antibiotics can lead to the development of persistent, non-replicating bacteria with the corollary that these persistent (yet viable) chlamydiae can resist eradication by further antimicrobial treatment and cause chronic disease. These findings highlight an urgent need for therapeutics that are effective against persistent infections and call for creative approaches to identify potential drug targets. The C. pneumoniae and C. trachomatis genome projects have greatly expanded our knowledge of chlamydial pathogenesis and have provided an enormous potential for the identification and characterization of unknown genes and potential virulence factors in these bacteria. As intracellular pathogens, chlamydiae rely on host cells for all aspects of their survival, from the initial attachment with host cell membranes, to cellular invasion, acquisition of host cell metabolites and intracellular replication. As such, the molecules participating in interactions with the host could be attractive targets for therapeutic intervention. This review describes recent advances in chlamydial genomics, proteomics and cell biology that have cast light on host-pathogen relations that are essential for chlamydial survival. Using this knowledge, we discuss how strategically interfering with essential interactions between chlamydiae and the host cell could be exploited to develop an innovative, and potentially more relevant arsenal of therapeutic compounds.

Ciliary function, cell viability, and in vitro effect of ribavirin on nasal epithelial cells in acute rhinorrhea.

Nasal epithelial (NE) cells were collected from the nasopharynx of 25 individuals with symptomatic colds and 27 healthy volunteers (controls), and ciliary beat frequency (CBF) was assessed by microscopy employing video motion analysis techniques. Baseline CBF was statistically significantly elevated in the group with colds compared to the control group (14.6 +/- 1.5 Hz [mean +/- SD] vs 13.8 +/- 0.9 Hz; p = 0.02). After four days of incubation in culture, there was a significant decrease in the CBF in both groups, with a change from baseline of 1.9 Hz for the cold group, compared to 1.0 Hz for the control group (p = 0.0001). The in vitro addition of ribavirin at 500 micrograms/ml to NE cells from individuals with colds preserved the viability of the cells and maintained the CBF at baseline values. Twenty-four (96 percent) of 25 ribavirin-treated specimens from the cold group survived for four days in culture, compared with 17 (68 percent) of 25 untreated cold specimens. In addition, the ribavirin-treated cells had a mean CBF of 14.2 +/- 1.3 Hz, compared with 12.7 +/- 1.9 Hz for the untreated cell samples (p = 0.0005). Ribavirin had no effect on NE cells from the control group. These results suggest that ribavirin in a concentration of 500 micrograms/ml may have some benefit in the treatment of acute rhinorrhea.

Chlamydial antibodies in children with lower respiratory disease.

Forty-nine of 255 (19.2%) Argentinean children between the ages of 1 and 18 months without evidence of viral or bacterial infections, but with clinical and radiologic evidence of acute lower respiratory distress, had serologic evidence of recent Chlamydia trachomatis infection by the demonstration of specific IgM, seroconversion or 4-fold rise in titer or elevated titers by enzyme immunoassay and the microimmunofluorescence test. Recent C. trachomatis infection was detected in 28 of 166 (16.9%) of children with bronchiolitis and 18 of 89 (20.2%) with pneumonia. Three additional children with bronchiolitis had Chlamydia pneumoniae-specific antibody. There was a significantly higher prevalence of C. trachomatis infection in children living in La Plata city orphanage (26 of 74, 35.1%) than in those attending 2 pediatric hospitals in Buenos Aires (23 of 181, 12.7%) (P less than 0.001). C. trachomatis infection was detected in all age groups up to 18 months. Thirty of 49 infections were in children older than 3 months of age and 16 were in children older than 6 months. These results suggest that C. trachomatis infection may be associated with bronchiolitis and pneumonia in children between the ages of 1 and 18 months of age in Argentina and that a proportion may be horizontally transmitted.

Role of Ureaplasma urealyticum and other pathogens in the development of chronic lung disease of prematurity.

A prospective cohort study enrolling 107 infants weighing less than 1250 g was conducted between September 1, 1986, and November 15, 1987 in order to determine the role of microorganisms on the development of chronic lung disease (CLD). Ureaplasma urealyticum was isolated significantly more frequently from gastric aspirates and nasopharyngeal or endotracheal aspirates from 43 infants developing CLD than from 56 who did not (51% vs. 16%; P less than 0.005). Infants developing CLD, defined by radiographic and blood gas abnormalities, were significantly younger (26 vs. 29 weeks; P less than 0.0001), weighed significantly less (830 vs. 1050 g; P less than 0.0001) and required more ventilatory support (37 vs. 10 were being ventilated and 42 vs. 26 received oxygen supplementation on Day 7) compared with those who did not develop CLD. Viruses were isolated in association with U. urealyticum in two infants developing CLD and in one infant who did not develop CLD. Mycoplasma hominis was isolated from three infants who were colonized with U. urealyticum and developed CLD. Chlamydia trachomatis was not recovered from any patients. From a discriminant analysis it was found that U. urealyticum contributed to the development of CLD along with the effect of ventilatory support, gestational age and severity of initial respiratory disease. The effect of interventions directed against U. urealyticum on the development of CLD deserves further study.

Predictors of positivity for hepatitis B and the derivation of a selective screening rule in a Canadian sexually transmitted disease clinic.

OBJECTIVES: To determine the prevalence of hepatitis B surface antibody (anti-HBs) and antigenemia (HBsAg), the risk factors for seropositivity and the effectiveness of a selective serologic screening rule among sexually transmitted diseases (STD) clinic attendees. STUDY DESIGN: Clients in the Hamilton STD Clinic were surveyed from October 1992 to July 1993 on sociodemographic, past medical, and behavioural data, were tested for several STDs and were offered serological testing and vaccination against hepatitis B. Predictors of seropositivity were determined by single variable analysis. A selective serologic screening rule was derived using logistic regression modelling. RESULTS: The seroprevalence of anti-HBs was 6.8% (21/310) in the 310 of 385 clients (80.5%) who agreed to be tested and interviewed. There were no HBsAg carriers. Five independent risk factors were identified by logistic regression: (1) age greater than 35 years; (2) birth outside Canada and histories of; (3) syphilis; (4) gonorrhoea; or (5) injection drug use. If clients with at least one of these predictors had been tested, 34.5% would have been selected for serologic testing and 85.7% of all positives would have been detected. The screening rule was more effective for men than for women. CONCLUSION: In this low prevalence setting, selecting STD clinic clients based on the presence of any one of five risk predictors appears to be an effective strategy for hepatitis B serologic screening in the context of a Canadian vaccination program.

Nucleic acid sequence based amplification (NASBA) of Chlamydia pneumoniae major outer membrane protein (ompA) mRNA with bioluminescent detection.

Chlamydia pneumoniae has been associated with chronic conditions such as atherosclerosis and coronary heart disease but the precise role of this intracellular bacteria in the pathogenesis of these diseases is not well defined. Several techniques have been developed for detection of C. pneumoniae in atheromatous lesions, however it remains unclear whether persistent forms of the organism and/or actively replicating bacteria contribute to associated pathology. The aim of this study was to utilize nucleic acid sequence based amplification (NASBA) technology together with a highly sensitive aequorin bioluminescent hybridization assay for the detection of C. pneumoniae ompA mRNA transcripts. A NASBA targeting the ompA gene of C. pneumoniae was developed, and the sensitivity was evaluated using both C. pneumoniae ompA RNA generated in vitro, and purified C. pneumoniae inclusion forming units (IFU). C. pneumoniae NASBA was capable of detecting between 100 and 1000 ompA RNA molecules and could detect 0.2 IFU of C. pneumoniae using the aequorin bioluminescent assay. The sensitivity of the bioluminescent assay was at least 10-fold higher than Northern blot detection. The linearity of NASBA amplification was assessed in time-course amplification experiments with different input numbers of RNA molecules. When NASBA products were analyzed during the linear phase of amplification, the dynamic range of bioluminescent detection extended over 8-log units of input RNA copy number. NASBA amplification coupled with bioluminescent detection may prove to be a useful molecular tool for the detection, quantitation and analysis of differentially expressed chlamydial genes during various stages of infection and disease pathology or for other mRNAs of interest in different disease processes.

Quantitation of Chlamydia trachomatis 16S rRNA using NASBA amplification and a bioluminescent microtiter plate assay.

We developed a nucleic acid sequence based amplification (NASBA) assay which employs the recombinant photoprotein Aequorin in a microtiter plate format for detection and quantitation of C. trachomatis that may be useful in large scale epidemiological studies aimed at improving our understanding of factors affecting transmission of this sexually transmitted pathogen. The conditions for NASBA amplification of the16S rRNA target were optimized (90 mM KCl, 12 mM MgCl(2), 0.2 microM P1 and P2 primers), amplified RNA was captured by a biotin-labelled capture probe immobilized onto streptavidin coated microtiter plates and detected with an FITC-labelled oligonucleotide probe and Aequorin-anti-FITC antibody conjugate. The analytical sensitivity of NASBA was 1,000 in vitro generated RNA transcripts and 1.6 IFU of C. trachomatis. The sensitivity of NASBA using the bioluminescent assay was 10 fold higher than Northern blotting. Time course amplification experiments performed with 10 fold serial dilutions of target established that amplification was linear at 75 min and extended over a range of five log units of input RNA copy number. Linear regression analysis confirmed a linear fit for the data with r(2) = 0.959 (p < 0.004). A double log plot of RLU signal versus copy number was linear; analysis of residuals from a series of runs tests confirmed a fit with a linear model (number of runs = 3, p = 0.5 where p < 0.05 indicates statistical deviation from a linear model). NASBA amplification coupled with bioluminescent detection in a microtiter plate format should provide a useful tool for quantitation of C. trachomatis in clinical specimens for use in epidemiological studies.

Abnormalities of antibody production after thermal injury. An association with reduced interleukin 2 production.

Antibody (Ab) production was studied in 25 burned patients who were immunized with 0.5 mg of tetanus toxoid adsorbed. Anti-tetanus toxoid (TT) Ab was measured by hemagglutination, radial immunodiffusion, and an enzyme-linked immunosorbent assay, and the results for the patients were compared with those for five similarly immunized healthy controls. As measured by hemagglutination, 12 (63%) of 19 patients had lower Ab responses than all five controls (P less than .05 by chi 2), and the median Ab response during the period of maximum response was significantly less than that in controls (8 vs 15.5 log2 maximum dilution; P = .014). After the initial response, serum Ab levels were not maintained in patients, in contrast to controls. This pattern was demonstrated by all three assays; enzyme-linked immunosorbent assay demonstrated that IgG anti-TT Ab was the major class of Ab produced. In nine patients interleukin 2 production by T lymphocytes was measured simultaneously; it was significantly depressed throughout the study except during the period from 36 to 45 days. The Ab response was also impaired in this patient group. Since maintained antibody production in response to TT is known to be T-cell dependent, these results suggest that inadequate interleukin 2 production leading to reduced T-cell help may be responsible for the lack of a persistent Ab response in these burned patients.

Combined testing for antibodies to rubella non-structural and envelope proteins sentinels infections in two outbreaks.

Two separate outbreaks of Rubella occurred in Hamilton, Ontario, Canada, 7 yrs apart, with a peak incidence for both in the month of April. A total of 138 cases, 51 in 1978 and 87 in 1985, was observed, the majority being in adolescents and young adults 15-25 years of age. Cases were diagnosed by the presence of Rubella IgM antibody or the combination of a negative passive hemagglutination (Rubacell-Abbott) and a positive enzyme immunoassay (EIA) or hemagglutination inhibition (HI) test on a single serum or by seroconversion for Rubella IgG antibody. Routine screening of sera with the Rubacell test, which measures antibodies to nonstructural rubella proteins together with HI or EIA testing of the negatives, served as a sentinel for rubella infection in the community during both outbreaks. Rubacell antibodies usually appeared 2-3 wk after onset of infections, and when present contained either or both IgG and IgM. Only 8/103 cases had a history of Rubella vaccination. Two of three products of conception yielded rubella virus in cell culture.

Effect of routine use of a multiplex PCR for detection of vanA- and vanB- mediated enterococcal resistance on accuracy, costs and earlier reporting.

A multiplex PCR (MPCR) for detection of vanA-and vanB-mediated resistance to vancomycin was optimized and adapted for use in the routine microbiology laboratory. Consecutive specimens (1196) submitted for vancomycin resistant Enterococci (VRE) surveillance were processed by clinical technologists on Bile Esculin Azide Agar containing 6 mg/L vancomycin (BEAA/Vanco6) plates and 466 showing black colony growth were processed by conventional biochemical testing (CBT) and by MPCR. CBT identified 208 VRE positives. MPCR detected 205 of the CBT- positives plus an additional 10. Analysis of the discordant specimens determined that 5 CBT- negative/MPCR-positive specimens also contained Enterococci with vanC resistance, 3 CBT-positive/MPCR-negative specimens were true positives, and 5 CBT-negative/MPCR-positive specimens occurred due to technical error. The sensitivity and specificity of MPCR were 98.4% and 96.1%. MPCR identifications of VRE were achieved approximately 48 h earlier than CBT and at 60% of the costs.

Chlamydia pneumoniae and atherosclerosis: does the evidence support a causal or contributory role?

The intracellular bacterial pathogen Chlamydia pneumoniae causes respiratory tract infection and has been associated with atherosclerosis and coronary artery disease. Since atherosclerosis is a progressive disease and is considered to be a chronic inflammation of the artery vessel wall, the interaction of C. pneumoniae with cells of the vasculature that can result in a local inflammatory response is of paramount importance. In this essay we review the pathophysiology of atherosclerosis in the context of C. pneumoniae infection and present an integrated model that includes the involvement of C. pneumoniae in all stages of atherogenesis including initiation, inflammation, fibrous plaque formation, plaque rupture and thrombosis. We hypothesize that acute and persistent infection of professional immune cells (T-cells, monocytes and macrophages) and non-immune cells (endothelial cells and smooth muscle cells) contributes to a sustained inflammatory response mediated by extensive cellular 'crosstalk' and numerous cytokines/chemokines. This cascade of inflammatory mediators may contribute to cellular dysfunction and tissue remodelling of the arterial intima. An improved understanding of the precise mechanism(s) of C. pneumoniae involvement in atherogenesis may help resolve the question of causality however, at the present time, we interpret the data as favoring a contributory rather than a causal role. Future research directed at the discovery of chlamydial virulence factors necessary for intracellular survival and subsequent alterations in host cell gene expression including signalling pathways may be important for the design of future clinical trials.

Cost and performance analysis of haemagglutination inhibition, passive haemagglutination, radial haemolysis, and enzyme immunoassay for measuring rubella antibody.

Cost and performance of non-commercial haemagglutination inhibition (HI) and radial haemolysis (RH) tests, and the commercially available passive haemagglutination (PHA) Rubacell and enzyme immunoassay (EIA) and Rubazyme assays were compared in their ability to detect rubella antibodies in 316 sera. Correlation coefficients were: HI to RH 0.96; HI to EIA 0.86. All 4 tests were in agreement on pre- and post-rubella immunization sera from 10 subjects. Eleven sera collected between 1 and 15 days after natural infection possessed clear HI titres whereas only 4 of them showed positive responses by PHA, RH or EIA. Immunity screening 285 sera identified 7 discordant results (positive in 2 of 4 tests). A detailed cost analysis for testing 100 sera showed a cost per test from +2.10 for HI to +3.71 for EIA. The labour component of the total cost was different for each assay and affected the unit cost of testing a single specimen. Results are discussed in view of antibody responses to specific rubella polypeptides and recommendations for diagnosis or immunity screening are made according to the findings.

A new immune complex dot assay for detection of rotavirus antigen in faeces.

A new immune complex dot assay (ICDA) using immune gold/silver staining is described for the sensitive and rapid detection of rotavirus in cell culture and stool specimens. The method involves spotting preformed antigen-antibody complexes onto nitrocellulose paper, followed by incubation with colloidal gold-labelled secondary antibody and silver enhancement. ICDA was sensitive and specific and detected rotavirus antigens over a wide range of concentrations. It was more sensitive than a conventional immunodot assay (CIDA) and two commercial enzyme immunoassays (EIA) based on testing serial dilutions of a positive stool specimen. Of 26 stool specimens tested ICDA detected rotavirus antigen in 17; 14 were positive by Pathfinder Rotavirus EIA, 16 by Testpack Rotavirus EIA, and direct electron microscopy (DEM) detected only 12. The ICDA offers improved sensitivity over commercial EIAs and DEM.