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J Burans

Publications and source records attributed to J Burans.

13 recordsLinked to original sources
PubMed2000

Early diagnosis of bubonic plague using F1 antigen capture ELISA assay and rapid immunogold dipstick.

Plague is still prevalent in more than 20 countries. Two F1 antigen diagnostic assays (an immunocapture ELISA and an immunogold chromatography dipstick) were evaluated using bubo aspirates, serum and urine specimens from patients suspected with plague. The specificity of the two F1 assays was found 100%. Using bacteriology as a gold reference diagnostic assay, 52 patients were Yersinia pestis culture positive and 141 negative. The sensitivity of the F1 ELISA test was 100% in bubo, 52% in serum and 58% in urine specimens. In culture negative patients, the F1 antigen could be found in 10% bubo aspirates, 5% serum and 7% urine specimens of culture negative patients for whom a seroconversion for anti-F1 antibodies was also observed. The sensitivity of the dipstick assay was 98% on bubo aspirates specimens. Compared to the ELISA test, the agreement rate was 97.5% and the correlation coefficient tau = 0.90 (p < 10(-3)). In conclusion, the diagnosis of bubonic plague has to be performed on bubo fluid rather than on serum or urine specimens. Both the F1 ELISA and the dipstick assays are valuable tools for an early diagnosis and for the surveillance of plague.

Antibodies, Monoclonal↗
PubMed2000

Field detection of Francisella tularensis.

A field investigation was undertaken following an outbreak of water-borne tularemia in Northern Norway. Francisella tularensis bacterial cellular components were analysed by rapid immunochromatography (RI)-testing, enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). Water from 1 reservoir, fed from a rapid stream, tested negative. From another reservoir, 2 of a chain of 3 wells tested negative. The third well, at the end of the chain, contained lemming (Lemmus lemmus) carcasses and gave ample proof of F. tularensis contamination. We concluded that the origin of the outbreak was dead, infective lemming carcasses in the water sources. For the various sampling materials, the RI-test proved itself particularly handy and versatile, compared with the ELISA and the PCR.

Chromatography↗
PubMed1999

Shipboard impact of a probable Norwalk virus outbreak from coastal Japan.

Norwalk virus has been implicated in shipboard diarrheal disease outbreaks throughout Asia. A large outbreak of suspected Norwalk virus was investigated on a U.S. Naval aircraft carrier following the clinical recognition of 450 cases of gastroenteritis over a 2-week period (September 14-28, 1997) during coastal exercises. A random sampling of 44 cases from 450 personnel who sought medical attention was compared with 19 controls. Junior enlisted sailors and marines comprised 97% of all cases. There was no evidence of shipboard geographic clustering of cases. Furthermore, no single food type was associated with illness on the basis of comparative analysis (cases versus controls). Principal case signs and symptoms reported included watery stools (89%), nausea (82%), and vomiting (77%). Anecdotal reports indicated > 50% of the cases received rehydration therapy. An absence of fever was also noted in 32% of the cases and only 5% had blood in their stools. The mean duration of illness was 37 hr, with a range of 3-96 hr. Laboratory findings based on reverse transcription-polymerase chain reaction and Southern hybridization methods showed that 21 (72%) of 29 patients had evidence of the UK2 prototype of the Norwalk virus. A cross-sectional study of 131 crew members from the ships population (n = 4,200) showed an attack rate of 44%. Attack rate is a variant of an incident rate applied to a narrowly defined population observed for a limited period of time, such as during an outbreak. The numerator is people who get sick and the denominator is people (population) at risk. An extrapolation of these findings suggests as many as 1,806 sailors may have been affected during the outbreak, of which only 26% (of the 57 outbreak related cases) where identified from sick call records. There was no difference in the mean ages between outbreak and non-outbreak affected crewmen, or geographic clustering based on berthing or work spaces. Outbreak-related cases reported signs and symptoms of watery-stools (79%), nausea (65%), and vomiting (47%). The mean duration of illness was 28 hr, ranging from 2 to 96 hr. Thirty-one percent of outbreak affected cases reported a sick call visit. Loss of work was reported by 39% of the outbreak affected population. This report documents the epidemic potential of Norwalk virus and the associated impact on fleet operational readiness. Additionally, that this outbreak occurred against a background of 3 other consecutive gastroenteritis outbreaks onboard the same ship (March 1997, February/March 1998, and June 1998), all sharing the same clinical and epidemiologic profiles, suggests possible shipboard persistence of Norwalk virus over time, despite periodic ship-wide disinfection efforts.

Adult↗
PubMed1997

Fiber optic-based biosensor for ricin.

We report on an evanescent wave fiber-optic biosensor for detecting a potently toxic protein, ricin, in the picograms per milliliter range. A sandwich immunoassay scheme was used to detect ricin. First, an anti-ricin IgG was immobilized onto the surface of an optical fiber in two different ways. In the first method, the antibody was directly coated to the silanized fiber using a crosslinker. Second, avidin-coated fibers were incubated with biotinylated anti-ricin IgG to immobilize the antibody using an avidin-biotin bridge. The assay using the avidin-biotin linked antibody demonstrated higher sensitivity and wider linear dynamic range than the assay using antibody directly conjugated to the surface. The linear dynamic range of detection for ricin in buffer using the avidin-biotin chemistry is 100 pg/ml-250 ng/ml. The limits of detection for ricin in buffer solution and river water are 100 pg/ml and 1 ng/ml, respectively. At higher concentrations of ricin (> 50 ng/ml), we observe a strong interaction of ricin with the avidin coated on the surface of the fibers. We have demonstrated that this interaction is primarily due to the lectin activity of ricin and is significantly reduced using fibers coated with neutravidin or by adding galactose to the ricin samples.

Adsorption↗
PubMed1996

Directing antigen specificity towards botulinum neurotoxin with combinatorial phage display libraries.

The production of antibodies towards antigens with low immunogenicity is enhanced by the intrinsic efficiency of screening combinatorial libraries of immunoglobulins. The need to isolate clones with rare binding specificities has dictated a highly efficient method of screening and isolating antibody clones. The production of recombinant immunoglobulin libraries in bacteria allows for a more controlled selection of antibody specificity and can be used in circumstances where hybridoma fusions are unable to isolate rare clones with the desired epitope specificity. Botulinum neurotoxin (NT) with associated non neurotoxin proteins (non-NT) as a complex was used to immunize mice to obtain mRNA for the production of a recombinant antibody library with a repertoire of specificities. Initial screens of the combinatorial library revealed clones which recognized the non-neurotoxin proteins of the toxin complex similar to monoclonal antibodies produced by conventional hybridoma fusions. The combinatorial library was re-screened in order to isolate antibodies that specifically recognized the neurotoxin component of the toxin complex. The ability to alter the biopanning selection process affords the researcher a measure of control in the selection process not available with traditional hybridoma fusions.

Animals↗
PubMed1996

Short-term IgM and IgG antibody responses to hepatitis E virus infection.

53 adult patients with acute hepatitis caused by hepatitis E virus were identified by the presence of IgM antibody to hepatitis E virus, and followed for 12 months to evaluate the kinetics of anti-HEV antibodies. All but 1 female Kuwaiti patient were expatriate workers from the Indian subcontinent, temporarily working in Kuwait. Follow-up samples obtained at 1, 3, 6 and 12 months were evaluated for IgM and IgG antibodies to hepatitis E virus. IgM-class antibodies to hepatitis E virus were detectable in 12/27 (44%) patients at 1 months, in 0/26 at 3 months, in 0/8 at 6 months and 0/6 at 12 months. IgG antibodies to hepatitis E virus were detectable in 46/47 (98%) at onset, 26/27 (96%) at 1 month, in 26/29 (90%) at 3 months, 16/16 (100%) at 6 months and 8/8 (100%) at 12 months of follow-up. This study suggests that IgM antibodies to hepatitis E virus decline rapidly after an acute infection but IgG antibodies to hepatitis E virus persists for at least 1 year in many patients.

Acute Disease↗
PubMed1994

Acute sporadic hepatitis E in Kuwait.

Fifty-seven adult patients with acute hepatitis and 34 comparison patients without liver disease were evaluated using a newly developed Western blot assay for IgM antibody to hepatitis E virus. The mean age of patients with hepatitis was 32 years (range, 18-55 years); 88% were male. Among patients with acute hepatitis, hepatitis A (anti-HAV IgM positive) was diagnosed in two (4%), hepatitis B (anti-HBc IgM positive) in three (5%), and hepatitis E (anti-HEV IgM positive) in 34 (60%). One hepatitis patient had CMV IgM, another had EBV IgM, and 16 others (28%) were negative for all serologic markers of acute viral hepatitis. No patient with acute hepatitis A or B and none of the comparison patients without acute hepatitis had anti-HEV IgM. All but one case of acute hepatitis E were found among expatriates of Asian origin, and acute hepatitis E was associated significantly with recent travel to the Indian subcontinent. These data suggest that acute hepatitis E is common among foreign workers in Kuwait but that little HEV transmission is occurring directly in Kuwait.

Acute Disease↗
PubMed1994

A rapid method for detection and identification of flaviviruses by polymerase chain reaction and nucleic acid hybridization.

A polymerase chain reaction (PCR) technique was developed and evaluated for the detection of flaviviruses. A set of sense and antisense oligomeric DNA primers were constructed from nucleotide sequences of the conserved region of the genome of several different flaviviruses. Virus specific complementary DNA (cDNA) was prepared by reverse transcription of total RNA extracted from infected cell cultures. Amplified cDNA was identified by nucleic acid hybridization with specific oligomeric internal probes. Various conditions, such as number of cycles and annealing temperature were examined to optimize the detection of viral RNAs from infected cell cultures. Slot blot hybridization with a radioactive probe was used to evaluate the sensitivity of PCR amplification. The PCR amplified RNA sequences of dengue 2 (DEN-2), West Nile (WN), St. Louis encephalitis (SLE) and Kunjin (KUN) virus and detected 0.1 to 1 pg of viral RNA. Japanese encephalitis (JE), Yellow Fever virus (YF), DEN-1, 3, and 4 viruses were not amplified. The more frequent occurrence of mismatches in the 3' primer binding site may explain the failure to amplify cDNA of these viruses.

Aedes↗
PubMed1994

Highly resistant bacterial osteomyelitis in Somalia.

Chronic osteomyelitis is a major health problem in the aftermath of the conflict in Somalia. We studied the microbiology of chronic osteomyelitis among 30 patients in a large hospital in Mogadishu. Gram-negative bacteria were isolated from 77% of patients; most of these isolates were highly resistant to standard antibiotic agents but all were sensitive to ciprofloxacin, an oral fluoroquinolone antibiotic. Ciprofloxacin may prove useful in the management of chronic osteomyelitis due to highly resistant gram-negative bacteria.

Chronic Disease↗
PubMed1993

Acute sporadic hepatitis E in an Egyptian pediatric population.

A study was conducted to determine the etiology of acute hepatitis among 261 children (age range 1-11 years) living in Cairo, Egypt. A blood sample was obtained from each subject when initially evaluated and a questionnaire was used to collect demographic and risk factor data. Sera were tested by enzyme immunoassay for acute hepatitis A (anti-hepatitis A virus IgM), hepatitis B (anti-hepatitis B core antigen IgM and hepatitis B surface antigen [HBsAg]), hepatitis C (total anti-HCV), delta hepatitis (total anti-delta), and cytomegalovirus infection (anti-CMV IgM). In addition, hepatitis E virus (HEV) infection was diagnosed using a new Western blot technique to test patients with non-A, non-B hepatitis for anti-HEV IgM. Among 261 children, acute hepatitis A was diagnosed in 85 (32.6%) patients, acute hepatitis B in 19 (7.3%), delta hepatitis in 3 (1.1%), mixed hepatitis A and B infection in 2 (0.8%), CMV infection in 1 (0.4%), hepatitis E in 58 (22.2%), and non-A, non-B hepatitis of unknown type in 51 (19.5%). Forty-two (16.1%) subjects had HBsAg without other markers of acute infection. Risk factor analysis indicated that patients living in homes not connected to a municipal source of water were at increased risk of hepatitis E infection. These data provide additional evidence that hepatitis E virus is a common cause of acute sporadic hepatitis in children living in Egypt.

Acute Disease↗
PubMed1993

The Navy Forward Laboratory during Operations Desert Shield/Desert Storm.

The Navy Forward Laboratory (NFL) was an advanced infectious disease laboratory which provided a theater-wide reference diagnostic capability during Operations Desert Shield/Storm. During Operation Desert Shield, when massive numbers of troops were being deployed, the NFL primarily supported medical personnel in the diagnosis and treatment of infectious diseases. During the war, the laboratory provided rapid biologic warfare diagnostic support. The NFL demonstrated the benefits of a comprehensive, on-site diagnostic laboratory when large numbers of troops are deployed to high-risk areas and demonstrated the importance of military medical research laboratories for training of scientists and physicians, threat assessment, and product development.

Humans↗