Biomedical subjects

David Wagner

Publications and source records attributed to David Wagner.

7 recordsLinked to original sources

PubMed2007

Malakoplakia of the prostate on needle core biopsy: a case report and review of the literature.

Malakoplakia is a rare inflammatory disorder that results from an infectious process and that may be associated with immunosuppression. It most often occurs in the genitourinary tract; however, isolated cases have been reported in many other organs, including colon, stomach, lung, liver, bone, uterus, and skin. In the bladder, which is the most common site of involvement, it may be mistaken for malignancy on cystoscopic examination or computerized topography scan. Gram-negative bacteria such as Escherichia coli and Klebsiella pneumonia are often isolated from malakoplakia lesions, although other less common bacteria such as Rhodococcus equi may also be found. This is a case report of prostatic malakoplakia diagnosed on needle core biopsy from a patient suspected to harbor a malignancy.

Aged↗

PubMed2006

Black carbon and polycyclic aromatic hydrocarbon emissions from vehicles in the United States-Mexico border region: pilot study.

The investigators developed a system to measure black carbon (BC) and particle-bound polycyclic aromatic hydrocarbon (PAH) emission factors during roadside sampling in four cities along the United States-Mexico border, Calexico/Mexicali and El Paso/Juarez. The measurement system included a photoacoustic analyzer for BC, a photoelectric aerosol sensor for particle-bound PAHs, and a carbon dioxide (CO2) analyzer. When a vehicle with measurable emissions passed the system probe, corresponding BC, PAH, and CO2 peaks were evident, and a fuel-based emission factor was estimated. A picture of each vehicle was also recorded with a digital camera. The advantage of this system, compared with other roadside methods, is the direct measurement of particulate matter components and limited interference from roadside dust. The study revealed some interesting trends: Mexican buses and all medium-duty trucks were more frequently identified as high emitters of BC and PAH than heavy-duty trucks or passenger vehicles. In addition, because of the high daily mileage of buses, they are good candidates for additional study. Mexican trucks and buses had higher average emission factors compared with U.S. trucks and buses, but the differences were not statistically significant. Few passenger vehicles had measurable BC and PAH emissions, although the highest emission factor came from an older model passenger vehicle licensed in Baja California.

Air Pollutants↗

PubMed2005

Real-time measurements of jet aircraft engine exhaust.

Particulate-phase exhaust properties from two different types of ground-based jet aircraft engines--high-thrust and turboshaft--were studied with real-time instruments on a portable pallet and additional time-integrated sampling devices. The real-time instruments successfully characterized rapidly changing particulate mass, light absorption, and polycyclic aromatic hydrocarbon (PAH) content. The integrated measurements included particulate-size distributions, PAH, and carbon concentrations for an entire test run (i.e., "run-integrated" measurements). In all cases, the particle-size distributions showed single modes peaking at 20-40nm diameter. Measurements of exhaust from high-thrust F404 engines showed relatively low-light absorption compared with exhaust from a turboshaft engine. Particulate-phase PAH measurements generally varied in phase with both net particulate mass and with light-absorbing particulate concentrations. Unexplained response behavior sometimes occurred with the real-time PAH analyzer, although on average the real-time and integrated PAH methods agreed within the same order of magnitude found in earlier investigations.

Air Pollutants↗

PubMed2004

Benefits and harms of doxycycline treatment for Gulf War veterans' illnesses: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: It has been hypothesized that certain Mycoplasma species may cause Gulf War veterans' illnesses (GWVIs), chronic diseases characterized by pain, fatigue, and cognitive symptoms, and that affected patients may benefit from doxycycline treatment. OBJECTIVE: To determine whether a 12-month course of doxycycline improves functional status in Gulf War veterans with GWVIs. DESIGN: A randomized, double-blind, placebo-controlled clinical trial with 12 months of treatment and 6 additional months of follow-up. SETTING: 26 U.S. Department of Veterans Affairs and 2 U.S. Department of Defense medical centers. PARTICIPANTS: 491 deployed Gulf War veterans with GWVIs and detectable Mycoplasma DNA in the blood. INTERVENTION: Doxycycline, 200 mg, or matching placebo daily for 12 months. MEASUREMENTS: The primary outcome was the proportion of participants who improved more than 7 units on the Physical Component Summary score of the Veterans Short Form-36 General Health Survey 12 months after randomization. Secondary outcomes were measures of pain, fatigue, and cognitive function and change in positivity for Mycoplasma species at 6, 12, and 18 months after randomization. RESULTS: No statistically significant differences were found between the doxycycline and placebo groups for the primary outcome measure (43 of 238 participants [18.1%] vs. 42 of 243 participants [17.3%]; difference, 0.8 percentage point [95% CI, -6.5 to 8.0 percentage points]; P > 0.2) or for secondary outcome measures at 1 year. In addition, possible differences in outcomes at 3 and 6 months were not apparent at 9 or 18 months. Participants in the doxycycline group had a higher incidence of nausea and photosensitivity. LIMITATIONS: Adherence to treatment after 6 months was poor. CONCLUSION: Long-term treatment with doxycycline did not improve outcomes of GWVIs at 1 year.

Adult↗

PubMed2003

Sensitivity in detecting free intraperitoneal fluid with the pelvic views of the FAST exam.

The multiple-view focused assessment with sonography for trauma (FAST) exam is an integral tool in the assessment of blunt abdominal trauma. A prospective observational study was performed to compute the average minimum volume of detectable intraperitoneal fluid with the pelvic views of the FAST exam. All adult patients from October 1999 to May 2001, who presented to the ED with blunt abdominal trauma and underwent a clinically indicated diagnostic peritoneal lavage (DPL), were candidates for admission to the pelvic ultrasound study. In the supine position, patients were administered lavage fluid in 100 cc increments until the examiner detected the fluid on ultrasound. An independent reviewer also examined the hard-copy ultrasound images for fluid detection. Patients were excluded if they had (1) a positive DPL for hemoperitoneum (defined as 10 cc of gross blood or >100,000 red blood cells/mL), (2) a positive initial ultrasound for free fluid, or (3) lacked sufficient hard-copy ultrasound images. The mean minimal volume of fluid needed for pelvic ultrasound detection by the examiner and reviewer was 157 and 129 cc (n = 7), respectively. The median quantity of fluid for ultrasound detection by both the examiner and reviewer was 100 cc. The pelvic views of the FAST exam identified a significantly smaller quantity of intraperitoneal fluid than previous studies of the right upper quadrant single-view exam.

Abdominal Injuries↗

PubMed2003

Combinatorial compound libraries for drug discovery: an ongoing challenge.

Almost 20 years of combinatorial chemistry have emphasized the power of numbers, a key issue for drug discovery in the current genomic era, in which it has been estimated that there might be more than 10,000 potential targets for which it would be desirable to have small-molecule modulators. Combinatorial chemistry is best described as the industrialization of chemistry; the chemistry has not changed, just the way in which it is now carried out, which is principally by exploiting instrumentation and robotics coupled to the extensive use of computers to efficiently control the process and analyse the vast amounts of resulting data. Many researchers have contributed to the general concepts as well as to the technologies in present use. However, some interesting challenges still remain to be solved, and these are discussed here in the context of the application of combinatorial chemistry to drug discovery.

Animals↗

PubMed2002

Comparative activity of gatifloxacin and other antibiotics against 4009 clinical isolates of Streptococcus pneumoniae in the United States during 1999-2000.

The susceptibility of 4009 recent clinical isolates of Streptococcus pneumoniae to gatifloxacin, levofloxacin, ciprofloxacin, penicillin, ceftriaxone and azithromycin was determined. Overall rates of susceptibility to these agents were 99.4, 98.7, 71.2, 55.2, 80.9, and 71.3%, respectively. Resistance to all tested agents was associated with penicillin resistance. Of penicillin nonsusceptible isolates, 36% were resistant. Resistance to the fluoroquinolones was unusual and gatifloxacin generally appeared to be four-fold more active than levofloxacin or ciprofloxacin. Multidrug resistant S. pneumoniae accounted for 6.2% of this sample. The lowest rate of susceptibility to non-fluoroquinolone antibiotics was observed in isolates from the South region of the United States, which appeared to be explained by both the proportion of and the inherently higher MICs of certain types of isolates.

Adolescent↗