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Biomedical subjects

J Powers

Publications and source records attributed to J Powers.

At least 73 records · Page 4Linked to original sources
PubMed1984

Sucking behaviors of normal 3-day-old female neonates during a 24-hr period.

Feeding behaviors were measured during six feeding sessions distributed throughout a 24-hr period in 10 normal 3-day-old female infants. Infants were individually videotaped during feeding sessions at 13:00, 17:00, 21:00, 01:00, 05:00, and 09:00 hours. Total mealtime, nutritive sucking time, pause time, number of nutritive sucks, and amount of nutrient consumed were measured. None of these feeding variables were affected by the time of day an infant was fed. Maternal interactions with their infants such as auditory stimulation, caretaking touches or tender touches were unaffected by the time of a feed. These maternal behaviors did not correlate with any of the feeding variables. These findings suggest that 3-day-old infants experiencing routine nursery care do not express specific day-night feeding differences and that certain maternal behaviors do not influence the infants' feeding pattern.

Feeding Behavior↗
PubMed1983

Senile dementia.

Explore the source record for details and available documents.

Brain Diseases↗
PubMed1980

Simultaneous evaluation of pancreatic exocrine function and intestinal absorptive function in dogs with chronic diarrhea.

The N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA):xylose test was evaluated in 5 clinically normal dogs, 5 dogs with pancreatic exocrine insufficiency (PEI), and 7 dogs with intestinal malabsorption. A solution of BT-PABA (1 g/100 ml) and d-xylose (10 g/100 ml) was given orally (5 ml/kg of body weight) to dogs in each group. Plasma p-aminobenzoic acid (PABA) curves were decreased in dogs with PEI and intestinal malabsorption (P < 0.05) but were the lowest in dogs with PEI, compared with clinically normal dogs. Xylose values in dogs with malabsorption were decreased (P < 0.05), compared with clinically normal dogs. Dogs with PEI had plasma xylose values that were intermediate to values in clinically normal dogs and dogs with intestinal malabsorption. Results of BT-PABA:xylose testing were compared with results of sodium PABA:xylose testing, to determine whether decreased PABA values obtained by the BT-PABA:xylose test were caused by free PABA malabsorption or by maldigestion of BT-PABA. The sodium PABA:xylose test was performed in dogs from each group by oral administration of a solution (5 ml/kg) of sodium PABA (0.372 g/100 ml) and d-xylose (10.0 g/100 ml). Plasma PABA values obtained by the sodium PABA:xylose test were similar in each group. Thus, different PABA values obtained by the BT-PABA:xylose test were not caused by PABA malabsorption. Xylose values were similar to values obtained by the BT-PABA:xylose test. It was concluded that: (1) the BT-PABA:xylose test is a practical test for detecting maldigestion or malabsorption in the dog; (2) dogs with intestinal malabsorption may have functional PEI; and (3) decreased PABA plasma values obtained by BT-PABA:xylose testing are not caused by malabsorption of free PABA.

4-Aminobenzoic Acid↗
PubMed1979

Human leucocyte elastase and cathepsin G: structural and functional characteristics.

Two of the major enzymes present in an released from neutrophil granulocytes are the endoproteinases elastase and cathepsin G. While the former is believed to be one of the major causative agents responsible for tissue destruction in emphysema and rheumatoid arthritis, little is known about the function of cathepsin G. We have recently developed simple procedures for isolating the isoenzymes of each type of proteinase as well as for their specific controlling plasma inhibitors. We have also prepared synthetic substrates and inhibitor analogues. Some sequence studies have been initiated and the results indicate homology of these enzymes not only with each other and with the pancreatic proteinases but also between cathepsin G and proteolytic enzymes present in muscle and mast cell tissue. Significantly, both types of enzyme can degrade the structural protein myosin, as well as elastin and proteoglycan. However, their relative importance in muscle protein turnover or muscle disease has not yet been clarified.

Amino Acid Sequence↗
PubMed1979

Virus-specified protease in poliovirus-infected HeLa cells.

Previous studies have shown that primary cleavages in nascent picornavirus precursors are accomplished by cellular proteases. This study has characterized the enzyme in infected cells that produces the capsid polypeptides by secondary cleavages of viral precursors. The kinetics of the production of protease activity correlate with the time course of virus protein synthesis, and the new enzyme has characteristic pH and temperature optima. Guanidine and cycloheximide, which are inhibitors of virus RNA and protein synthesis, prevent production of the protease. As determined by introduction of amino acid analogs into the protease or inhibition by a leucyl chloromethyl ketone, the enzyme is synthesized at a time of infection when host cell proteins are not produced, and the enzyme copurified with a 40,000-dalton virus polypeptide present in the cytoplasm of infected cells. Wild-type levels of protease activity are produced by viral mutants that are defective in coat protein synthesis. The conclusion is that a non-structural poliovirus gene product participates in protein cleavages that produce the viral coat proteins.

HeLa Cells↗
PubMedDate not supplied

Assessment of myocardial viability by dynamic tomographic iodine 123 iodophenylpentadecanoic acid imaging: comparison with rest-redistribution thallium 201 imaging.

BACKGROUND: This study examined the ability of dynamic 123I-labeled iodophenylpentadecanoic acid (IPPA) imaging to detect myocardial viability in patients with left ventricular (LV) dysfunction caused by coronary artery disease. METHODS AND RESULTS: Serial 180-degree single-photon emission computed tomographic (SPECT) images (five sets, 8 minutes each) were obtained starting 4 minutes after injection of 2 to 6 mCi 123I at rest in 21 patients with LV dysfunction (ejection fraction [EF] 34% +/- 11%). The segmental uptake was compared with that of rest-redistribution 201Tl images (20 segments/study). The number of perfusion defects (reversible and fixed) was similar by IPPA and thallium (11 +/- 5 vs 10 +/- 5 segments/patient; difference not significant). There was agreement between IPPA and thallium for presence or absence (kappa = 0.78 +/- 0.03) and nature (reversible, mild fixed, or severe fixed) of perfusion defects (kappa = 0.54 +/- 0.04). However, there were more reversible IPPA defects than reversible thallium defects (7 +/- 4 vs 3 +/- 4 segments/patient; p = 0.001). In 14 patients the EF (by gated pool imaging) improved after coronary revascularization from 33% +/- 11% to 39% +/- 12% (p = 0.002). The number of reversible IPPA defects was greater in the seven patients who had improvement in EF than in the patients without such improvement (10 +/- 4 vs 5 +/- 4 segments/patient; p = 0.075). CONCLUSIONS: 123I-labeled IPPA SPECT imaging is a promising new technique for assessment of viability. Reversible defects predict recovery of LV dysfunction after coronary revascularization.

Adult↗
PubMedDate not supplied

A sedation protocol for preventing patient self-extubation.

Inadequate sedation management can place critically ill patients in danger of self-injury. This article describes the development and use of a protocol for managing sedation in intubated patients to prevent injury from self-extubation. Critical care nurses can use the protocol to effectively manage agitation in intubated patients and prevent self-extubation.

Algorithms↗