Does a simple bedside sonographic measurement of the inferior vena cava correlate to central venous pressure?

Background: Bedside ultrasound has been suggested as a non-invasive modality to estimate central venous pressure (CVP).

Objective: Evaluate a simple bedside ultrasound technique to measure the diameter of the inferior vena cava (IVC) and correlate to simultaneously measured CVP. Secondary comparisons include anatomic location, probe orientation, and phase of respiration.

A practical influenza neutralization assay to simultaneously quantify hemagglutinin and neuraminidase-inhibiting antibody responses.

Influenza vaccine immunogenicity is commonly assessed by determining hemagglutination inhibition (HAI) titers in serum samples. HAI titers have been used to predict vaccine efficacy, but this often fails when live attenuated vaccines are evaluated, because it does not encompass all immune mediators of protection. Although antibodies that inhibit viral neuraminidase (NA) also contribute to protection against disease, there is currently no routine assessment of NA inhibition titers.

A miniaturized assay for influenza neuraminidase-inhibiting antibodies utilizing reverse genetics-derived antigens.

Background: Antibodies to neuraminidase (NA) contribute to protection during influenza virus infection, but NA inhibition (NI) titers are not routinely analyzed in vaccine trials. One reason is the cumbersome nature of the conventional thiobarbituric acid (TBA) NI assay, which uses chemical methods to quantify free sialic acid following incubation of NA with substrate in the presence of serum. In addition, the assay is complicated by the need to use virus of a hemagglutinin (HA) subtype novel to the host to detect NA-specific antibodies only.

Thrombocytopenia from combination treatment with oseltamivir and probenecid: case report, MedWatch data summary, and review of the literature.

The possibility of an avian flu pandemic has spurred interest in preventive treatments with antivirals such as oseltamivir. Combining treatment with probenecid to delay excretion may extend limited supplies of oseltamivir. We previously conducted a pharmacokinetic study of oseltamivir plus probenecid among healthy volunteers.

Clinical research regulation: challenges to the institutional review board system.

The system in place to ensure the ethical conduct of human subject research in accordance with federal regulations has drawn great criticism from all sides, to include clinical investigators, administrators, research subjects, and legislators. The administrative requirements associated with clinical trials has changed dramatically in the last several decades, as has the complexity of the science being regulated. The institutional review board (IRB) system, however, appears to be struggling to keep pace, and has even been labeled a "system in jeopardy" by a national committee of experts.

Pharmacokinetics and tolerability of oseltamivir combined with probenecid.

Oseltamivir is an inhibitor of influenza virus neuraminidase, which is approved for use for the treatment and prophylaxis of influenza A and B virus infections. In the event of an influenza pandemic, oseltamivir supplies may be limited; thus, alternative dosing strategies for oseltamivir prophylaxis should be explored. Healthy volunteers were randomized to a three-arm, open-label study and given 75 mg oral oseltamivir every 24 h (group 1), 75 mg oseltamivir every 48 h (q48h) combined with 500 mg probenecid four times a day (group 2), or 75 mg oseltamivir q48h combined with 500 mg probenecid twice a day (group 3) for 15 days.

Antibody contributes to heterosubtypic protection against influenza A-induced tachypnea in cotton rats.

Background: Influenza virus infection or vaccination evokes an antibody response to viral hemagglutinin (HA) and neuraminidase (NA) surface glycoproteins, which results in immunity against influenza A viruses of the same HA and NA subtype. A heterosubtypic immune response that offers some protection against different influenza A subtypes has been suggested from epidemiologic studies in human influenza outbreaks, and has been induced in experimental animal models. Original studies of such cross-protection showed that cytotoxic T lymphocytes (CTL) protect H3N2-immune mice from a lethal H1N1 infection.

Evidence of a cross-protective immune response to influenza A in the cotton rat model.

Epidemiologic evidence suggests that cross-protective immune responses to influenza A viruses that have different hemagglutinin and neuraminidase subtypes occur in humans. This study characterized this heterosubtypic immunity in cotton rats (Sigmodon hispidus). Animals were infected with influenza A/PR/8/34 (H1N1) or A/Wuhan/359/95 (H3N2), and then challenged with A/Wuhan/359/95(H3N2) virus 4 weeks later.

Defending against viruses in biowarfare. How to respond to smallpox, encephalitides, hemorrhagic fevers.

The threat of bioterrorism with use of viruses is increasing. Smallpox, encephalitis, and hemorrhagic fevers are the most likely diseases to result from viral deployment. It is critical that all healthcare professionals become familiar with the clinical presentation, diagnosis, management, and prevention of these diseases.