Search PubMed⌕ Search

Biomedical subjects

J Yee

Publications and source records attributed to J Yee.

At least 109 records · Page 6Linked to original sources
PubMed1990

Effects of various granulating systems on the bioavailability of naproxen sodium from polymeric matrix tablets.

Naproxen sodium and a cellulose ether derivative were granulated with either water or a poly(meth)acrylic acid ester copolymer aqueous dispersion to make three controlled-release matrix dosage forms. The different polymeric matrix systems contained hydroxypropyl methylcellulose (formulation A), hydroxypropyl cellulose:poly(meth)acrylic acid ester copolymer (formulation B), and hydroxypropyl methylcellulose:poly(meth)acrylic acid ester copolymer (formulation C). All three hydrophilic matrix tablets demonstrated identical in vitro dissolution rates. The three controlled-release formulations were compared with a marketed immediate-release naproxen sodium dosage form (formulation D) in a single-dose crossover study in six healthy volunteers. The AUC values for controlled-release dosage forms A and C were larger than those for formulations B and D. However, the reasons why the AUC for formulations A and C is larger than that for formulations B versus D can be explained differently. Formulations A and C more effectively maintain naproxen plasma levels than formulation D by reducing the amount of naproxen unbound to plasma proteins, therefore reducing naproxen available for urinary excretion. Naproxen sodium delivered from formulations A and C is also probably much better absorbed than from that from formulation B, possibly due to less drug entrapment. More importantly, although all three CR formulations had identical in vitro dissolution profiles, naproxen sodium plasma levels were better maintained (based on AUC) in subjects taking formulations A and C, which contained a lower polymer content and did not use hydroxypropyl cellulose. The tmax values were larger for the three controlled-release dosage forms. Also, the Cmax value for the conventional dosage form was nearly twofold higher than that observed for the controlled-release dosage forms.

Adult↗
PubMed1990

Characterization of monoclonal antibodies that distinguish simian immunodeficiency virus isolates from each other and from human immunodeficiency virus types 1 and 2.

Two monoclonal antibodies (MAbs) against p27 and one against p17 of simian immunodeficiency virus (SIV) from rhesus macaques were produced and characterized by reacting with disrupted, viral antigens on immunoblots. Human immunodeficiency virus type 1 (HIV-1), HIV-2 and SIV isolates from sooty mangabey, stump-tailed macaque, rhesus macaque and African green monkey (SIVSM, SIVStM, SIVMAC and SIVAGM) were used for comparative analysis. The p27 monoclonal antibodies HE3 and FA2 reacted with SIVMAC and SIVSM, but not with HIV-1, HIV-2, SIVStM and SIVAGM. The p17 monoclonal antibodies reacted with SIVMAC and SIVStM, but not HIV-1, HIV-2, SIVSM and SIVAGM. The differential reactivity of these monoclonal antibodies indicated that common conserved antigenic epitopes are shared between SIVMAC and SIVSM with respect to p27 MAbs and between SIVMAC and SIVStM with respect to p17. Since these MAbs reacted differently with the SIV isolates, they are useful reagents for comparative pathogenesis studies for differentiating SIV isolates.

Animals↗
PubMed1990

A family of genes encode the multiple forms of the Saccharomyces cerevisiae ribosomal proteins equivalent to the Escherichia coli L12 protein and a single form of the L10-equivalent ribosomal protein.

The budding yeast Saccharomyces cerevisiae contains a family of genes that encodes four different but related small acidic ribosomal proteins designated L12eIA, L12eIB, L12eIIA, and L12eIIB and a single larger protein designated L10e. These proteins are equivalent (e) to the L12 and L10 proteins of Escherichia coli that assemble as a 4:1 complex onto the large ribosomal subunit. The five yeast genes (or their cDNAs) have been cloned and sequenced (M. Remacha, M. T. Saenz-Robles, M. D. Vilella, and J. P. G. Ballesta, J. Biol. Chem. 263:9044-9101, 1988; K. Mitsui and K. Tsurugi, Nucleic Acids Res. 16:3573, 3574, and 3575, 1988; this work). Here, the transcripts of these genes were characterized and quantitated and the proteins they encode were compared and aligned. Four of the genes, L12eIA, -IB, -IIA, and L10e, are uninterrupted, whereas the L12eIIB gene contains a 301-nucleotide-long intron between codons 38 and 39. The transcripts derived from each of these genes were analyzed by Northern (RNA) hybridization, primer extension, and S1 nuclease protection. All five genes are expressed, albeit at different levels. The transcript levels are coordinate and exhibit growth rate-dependent regulation in rich (glucose) and poor (ethanol) media. The five yeast proteins each contain a highly conserved acidic carboxy terminus of about 20 residues in length. This domain of unknown function is also present in archaebacterial but absent from eubacterial L10e and L12e proteins. Comparisons of the factor-binding domains in the yeast and other eucaryotic and archaebacterial L12e proteins indicate that the original duplication to produce the type I and II genes was a very ancient event. The evolutionary relationships between the eucaryotic, archaebacterial, and eubacterial L10e and L12e genes (and proteins) are discussed.

Amino Acid Sequence↗
PubMed1990

Ketorolac tromethamine pharmacokinetics and metabolism after intravenous, intramuscular, and oral administration in humans and animals.

In humans, ketorolac is completely bioavailable and its kinetics are linear. It is absorbed rapidly (half-life for absorption 3.8 min) after oral (fasting) and intramuscular administration; food delays but does not reduce its absorption. The drug is highly protein bound in humans (greater than 99%). The mean plasma elimination half-life is 5-6 hours, and ketorolac is not extensively distributed outside the vascular compartment (Vd beta 15 L). Virtually all of the drug-related material circulating in plasma is in the form of ketorolac (greater than 96%), with the only metabolite the pharmacologically inactive p-hydroxyketorolac (PHK). Humans excrete about 90% of the administered dose in urine. About 60% of drug-related material recovered from urine is ketorolac, about 12% is PHK, and 28% represents polar, glucuronide conjugates of ketorolac. The animal models in which ketorolac's metabolism and kinetics are most similar to those in humans are the mouse and monkey, respectively.

Administration, Oral↗
PubMed1990

General surgical procedures after heart transplantation.

Seventy-eight cardiac transplantations were performed between July 1982 and March 1989. The perioperative death rate was 10%. Overall survival was 86%. Among the long-term survivors, 14 patients underwent 16 noncardiac surgical procedures. Seven of them required emergency laparotomy, four for biliary tract disease, one for ruptured abdominal aortic aneurysm, one for suspected abdominal sepsis and one for enterocolitis. Elective surgical interventions included repair of symptomatic abdominal wall hernia, treatment of hemorrhoids or perianal condylomas, total hip arthroplasty, maxillary sinus drainage and resection of a duodenal villous adenoma. Preoperatively, all patients received cyclosporine orally. Ten of the 14 patients were on triple-drug immunosuppression (cyclosporine, azathioprine and low-dose prednisone [less than 0.20 mg/kg daily]). The remaining four patients took cyclosporine with either azathioprine or prednisone. There were no deaths. Complications were limited to residual choledocholithiasis treated by percutaneous removal, two cases of wound infection and an incisional hernia. The authors' experience indicates that noncardiac surgical procedures may be safely performed in patients who have received a heart transplant.

Adult↗
PubMed1989

Antigen detection for human immunodeficiency virus.

The recent development of enzyme immunoassay procedures for the direct determination of human immunodeficiency virus (HIV) antigens has been of significant benefit in both clinical and research applications. The historical development of HIV antigen assays as well as their current and future applications for use in the clinical microbiology laboratory are reviewed. A detailed description of selected commercially available assays is presented, and a comparison is made of various parameters, including sensitivity, specificity, and cost. The use of the HIV antigen assay as an alternative to the reverse transcriptase assay in virus culture applications is also discussed. In addition, the diagnostic and prognostic utility of the HIV antigen assay is considered for various patient groups, including neonatal, high-risk asymptomatic, seronegative, and seropositive patient populations. The use of the HIV antigen assay as an adjunct to anti-HIV antibody testing, as well as its utility in assessing the therapeutic efficacy of antiviral drug therapy, is discussed. The biology of HIV antigen expression and modulation of anti-HIV antibody titers during infection are also discussed in terms of two possible models.

AIDS Serodiagnosis↗
PubMed1989

Organization of genes encoding the L11, L1, L10, and L12 equivalent ribosomal proteins in eubacteria, archaebacteria, and eucaryotes.

Archaebacterial and eucaryotic cytoplasmic ribosomes contain proteins equivalent to the L11, L1, L10, and L12 proteins of the eubacterium Escherichia coli. In E. coli the genes encoding these ribosomal proteins are clustered, cotranscribed, and autogenously regulated at the level of mRNA translation. Genomic restriction fragments encoding the L11e, L1e, L10e, and L12e (equivalent) proteins from two divergent archaebacteria. Halobacterium cutirubrum and Sulfolobus solfataricus, and the L10e and L12e proteins from the eucaryote Saccharomyces cerevisiae have been cloned, sequenced, and analyzed. In the archaebacteria, as in eubacteria, the four genes are clustered and the L11e, L1e, L10e, and L12e order is maintained. The transcription pattern of the H. cutirubrum cluster is different from the E. coli pattern and the flanking genes on either side of the tetragenic clusters in E. coli, H. cutirubrum, and Sulfolobus solfataricus are all unrelated to each other. In the eucaryote Saccharomyces cerevisiae there is a single L10e gene and four separate L12e genes that are designated L12eIA, L12eIB, L12eIIA, and L12eIIB. These five genes are not closely linked and each is transcribed as a monocistronic mRNA; the L10e, L12eIA, L12eIB, and the L12eIIA genes are contiguous and uninterrupted, whereas the L12eIIB gene is interrupted by a 301 nucleotide long intron located between codons 38 and 39.

Amino Acid Sequence↗
PubMed1988

'Crescendo' transient ischemic attacks: clinical and angiographic correlations.

Forty-seven consecutive patients presenting acutely with repetitive symptoms indicative of anterior circulation ischemia ("crescendo" transient ischemic attacks) were evaluated to identify clinical features that might reliably predict the presence of significant stenosis, ulceration, or both in the presumably symptomatic internal carotid artery. Angiographic or intraoperative correlation was obtained in all patients, and 26 (55%) were found to have anatomically significant disease. Of 20 patients with signs or symptoms suggestive of cortical ischemia, amaurosis fugax, or both, 17 (85%) had "positive" angiograms; of 18 with numbness/weakness only, 9 (50%) had positive angiograms; of 9 whose symptoms suggested lacunar ischemia, none had positive angiograms.

Aged↗
PubMed1987

Antibiotic prophylaxis for facial fractures. A prospective, randomized clinical trial.

Although antibiotics are widely used in an attempt to decrease the incidence of infections after facial fractures, no systematic prospective study of their efficacy has been performed. In this study, all adult patients with facial fractures who had not received antibiotics were asked to participate in a clinical trial. There were 101 patients with facial fractures enrolled into the study and randomized prospectively into two groups. One group received no antibiotics. The other group received cefazolin sodium, 1 g intravenously, one hour prior to the surgical procedure, and a similar dose eight hours later. Of the 101 patients enrolled in the study, 79 had mandibular fractures, 18 had zygoma fractures, and four had Le Fort fractures. When all facial fractures were considered, perioperative intravenous cefazolin reduced the incidence of postoperative infections; 42.2% in the no-antibiotic group became infected, and 8.9% in the antibiotic group became infected. On the basis of this study, we conclude that cefazolin, used perioperatively, diminished the incidence of postoperative infections in facial fractures.

Adolescent↗
PubMed1987

Evaluation of the two-needle strategy for reducing reactions to DPT vaccination.

Using a blinded crossover design, we tested the hypothesis that changing the needle on the syringe after drawing up diphtheria-pertussis-tetanus vaccine and before injecting it reduces local complications by eliminating deposition of aluminum phosphate adjuvant in the subcutaneous track of the needle. Two hundred twenty-three children (52.7%) received a two-needle vaccination while 200 (47.3%) received a one-needle vaccination. Three hundred forty-six parents (81.8%) returned a questionnaire reporting their child's reaction within 48 hours of injection. There was no significant difference in the occurrence of redness, swelling, tenderness, or limp or in parental measurements of redness and swelling between the one- and two-needle groups. Moreover, we found no differences in the frequency of systemic side effects, including fever, vomiting, anorexia, and crying. These results do not support the practice of changing needles to reduce diphtheria-pertussis-tetanus vaccine reactions.

Acute-Phase Reaction↗
PubMed1987

Osler's nodes and the recognition of infective endocarditis: a lesion of diagnostic importance.

Osler's nodes are classic lesions strongly associated with infective endocarditis. Osler's original description placed them as a frequent finding (70%) in cases of endocarditis. Recent literature, however, has infrequently described these lesions, which in general are no longer found to be useful. We review the clinical syndromes of infective endocarditis and their association with these lesions. We also review the pathogenesis of the lesion that currently supports the embolic nature of Osler's nodes. Osler's nodes are helpful clues if they appear in patients with infective endocarditis, and biopsy and culture of the lesion may provide an etiologic diagnosis.

Endocarditis, Subacute Bacterial↗
PubMed1987

Comparison of indirect immunofluorescence and Western blot for detection of anti-human immunodeficiency virus antibodies.

There was 100% agreement between the results of indirect immunofluorescence (IF) and Western blot testing when these methods were used to detect antibodies to the human immunodeficiency virus in sera from 25 patients with acquired immune deficiency syndrome (AIDS), 20 patients with AIDS-related complex, 186 subjects at high risk for AIDS, and 40 healthy heterosexuals. However, there was only an 88.7% correlation between IF and Western blot results for 728 sera from blood and plasma donor centers that were selected on the basis of screening enzyme immunoassay reactivity. IF tests yielded nine false-negatives and were equivocal, yielding a nonspecific pattern of reactivity for both infected and uninfected cells for 73 of these specimens. The IF and Western blot methods were equal in performance for the detection of anti-human immunodeficiency virus antibodies in the high-risk and unselected low-risk groups, proving to be a practical approach for testing specimens from these subjects. However, the Western blot was the most acceptable method for the validation of specimens from groups at low risk for AIDS that were selected based on enzyme immunoassay reactivity.

AIDS-Related Complex↗
PubMed1987

Use of furosemide in pregnancies complicated by oligohydramnios.

To differentiate pregnancies complicated by oligohydramnios due to intrauterine growth retardation from those due to renal agenesis, the authors administered furosemide intravenously to eight pregnant women (19-25 weeks gestation) with oligohydramnios. The fetal abdomen was scanned with ultrasound to demonstrate the fetal urinary bladder. In six fetuses, sonography failed to demonstrate the bladder: two fetuses had growth retardation with normal kidneys and bladder, and four had renal anomalies. It is concluded that administration of furosemide to the mother fails to induce diuresis in growth-retarded fetuses of 19-23 weeks gestation and that failure to see the fetal bladder after furosemide administration does not necessarily indicate absent fetal kidneys.

Amniotic Fluid↗
PubMed1987

The utility of Osler's nodes in the diagnosis of infective endocarditis.

The etiology of Osler's nodes remains controversial. We describe a patient with endocarditis in whom Streptococcus sanguis was grown from the biopsy of such a lesion. Bacterial embolic events are likely to be the major pathogenetic event in the development of Osler's nodes, and recognition of the etiology of infective endocarditis may be found through biopsy of them.

Endocarditis, Bacterial↗