ABSTRACT
Rotavirus nonstructural protein NSP4 has recently been suggested to function as a viral enterotoxin and play a role in the pathophysiological mechanism whereby rotaviruses induce diarrhea. The ability of rotavirus NSP4 to stimulate a humoral immune response was examined in naturally infected children and adults, rotavirus vaccinated children, as well as a cellular immune response in adults. In this study, 10 of 10 naturally infected children and 9 of 10 rotavirus-vaccinated children showed a weak humoral IgG immune response to recombinant NSP4 (rNSP4) and/or a synthetic peptide corresponding to residues 114-134 of NSP4. Modest serum IgG antibody responses were detected in 20 of 20 adults. A cellular immune response to rNSP4 and/or NSP4(114-134) were detected in 8 of 10 adults measured either as a T-cell proliferative response (7 of 10), an increased production of IL-2 (6 of 10), or increased production of interferon-gamma (8 of 10). These results indicate that NSP4 induces a humoral immune response in humans and show for the first time that NSP4 stimulates a cellular immune response, possibly including cytolytic T-cells.
Subject(s)
DNA-Directed RNA Polymerases , Rotavirus Infections/immunology , Rotavirus/chemistry , Viral Nonstructural Proteins/immunology , Adult , Antibodies, Viral/blood , Finland , Humans , Immunity, Cellular/immunology , Immunoglobulin A/blood , Immunoglobulin G/blood , Infant , Nicaragua , Recombinant Proteins/biosynthesis , Recombinant Proteins/immunology , Rotavirus/immunology , Rotavirus Infections/virology , Sweden , T-Lymphocytes/metabolism , Viral Nonstructural Proteins/biosynthesisABSTRACT
Two techniques of Doppler ultrasound examination, continuous-wave and range-gated, applied to the anterior cerebral artery and to the internal carotid artery, were compared with 133xenon clearance after intravenous injection. Thirty-two sets of measurements were obtained in 16 newborn infants. The pulsatility index, the mean flow velocity, and the end-diastolic flow velocity were read from the Doppler recordings. Mean cerebral blood flow was estimated from the 133Xe clearance curves. The correlation coefficients between the Doppler and the 133Xe measurements ranged from 0.41 to 0.82. In the subset of 16 first measurements in each infant, there were no statistically significant differences between the correlation coefficients of the various Doppler ultrasound variables, but the correlation coefficients were consistently lower for the pulsatility index than for mean flow velocity or end-diastolic flow velocity, and they were consistently higher for the range-gated than for the continuous-wave Doppler technique.
Subject(s)
Cerebral Hemorrhage/diagnosis , Cerebrovascular Circulation , Ultrasonography , Xenon Radioisotopes , Blood Flow Velocity , Diastole , Humans , Infant, NewbornABSTRACT
1-Various aspects of temperature regulation in the nine-banded armadillo, dasypus novemcinctus mexicanus, were studied, including measurements of rectal, skin, and muscle temperatures and of oxygen consumption and recording of electrocardiograms. 2-In a constant ambient temperature of 25 graus centígrados the animals showed a diurnal temperature cycle of maximum 2.5 graus. The lowest temperatures varied between 34 graus-35 graus and occurred in the early morning. The armadillo showed nocturnal habits, and the highest temperatures coincided with maximum activity at about midnight...