Biomedical subjects

R Willis

Publications and source records attributed to R Willis.

15 recordsLinked to original sources

PubMed1992

Serving the needs of donor families: the role of the critical care nurse.

The humanitarian act of donating organs has tremendous benefits not only for the transplant recipients but also for the family of the donor. The opportunity to provide some hope to a grief-stricken family that something positive can result from their tragedy is an important contribution that a critical care nurse can make. The nurse's participation in recognizing the possibility of organ donation for the family of a terminal patient can drastically reduce the national shortage of transplantable organs. The consent and organ recovery process is a complex one, and a team approach by the nurse, physician, OPO coordinator, and other hospital staff members is necessary. Ultimately, the success of the effort is determined by the family's positive response to give the "Gift of Life."

Adolescent↗

PubMed1991

Long-term indomethacin therapy decreases fetal urine output and results in oligohydramnios.

Four quadrant quantitative amniotic fluid volume (length, width, and depth) was performed in six fetuses prior to and during indomethacin therapy for preterm labor in patients with normal amniotic fluid volume prior to therapy. The dose of indomethacin was 25 mg orally every 6 hours. One patient had to have the dose reduced to 25 mg every 12 hours due to constriction of the ductus arteriosus. Fetal urine output was determined prior to and during indomethacin therapy. The mean pretherapy amniotic fluid volume of 341.5 +/- 43.2 mm declined to 97 +/- 9.3 mm at the time of discontinuation of indomethacin for oligohydramnios. This occurred after 15 days of 25 mg indomethacin orally every 6 hours in four patients and after 28 days at 25 mg indomethacin every 12 hours in the remaining patient. Fetal urine output prior to and following indomethacin was 4.93 +/- 14 ml and 1.73 +/- 0.6 ml/hr, respectively. Prolonged indomethacin therapy results in decreased fetal urine output with resultant oligohydramnios and appears to be the major limiting factor aside from ductal constriction to long-term indomethacin therapy.

Adult↗

PubMed1991

Stapedectomy--past and present.

Surgical technics for bypassing ankylosis of the stapes in the management of otosclerosis gradually evolved; modifications were prompted by problems which were revealed by the ongoing audits carried out by earlier surgeons. Auditing of performance must remain an integral part of any otologist's work. The natural history of otosclerosis should be taken into account so that a patient may be fully informed of treatment alternatives available. Stapedectomy will remain a most effective operation which can be recommended with confidence, provided the surgeon has acquired the skill to perform it properly. It is now accepted that many ear, nose and throat surgeons are neither physically nor temperamentally capable of this task and should not perform stapedectomy.

Female↗

PubMed1990

Lovastatin decreases coenzyme Q levels in humans.

Lovastatin is clinically used to treat patients with hypercholesterolemia and successfully lowers cholesterol levels. The mechanism of action of lovastatin is inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, an enzyme involved in the biosynthesis of cholesterol from acetyl-CoA. Inhibition of this enzyme could also inhibit the intrinsic biosynthesis of coenzyme Q10 (CoQ10), but there have not been definitive data on whether lovastatin reduces levels of CoQ10 as it does cholesterol. The clinical use of lovastatin is to reduce a risk of cardiac disease, and if lovastatin were to reduce levels of CoQ10, this reduction would constitute a new risk of cardiac disease, since it is established that CoQ10 is indispensable for cardiac function. We have conducted three related protocols to determine whether lovastatin does indeed inhibit the biosynthesis of CoQ10. One protocol was done on rats, and is reported in the preceding paper [Willis, R. A., Folkers, K., Tucker, J. L., Ye, C.-Q., Xia, L.-J. & Tamagawa, H. (1990) Proc. Natl. Acad. Sci. USA 87, 8928-8930]. The other two protocols are reported here. One involved patients in a hospital, and the other involved a volunteer who permitted extraordinary monitoring of CoQ10 and cholesterol levels and cardiac function. All data from the three protocols revealed that lovastatin does indeed lower levels of CoQ10. The five hospitalized patients, 43-72 years old, revealed increased cardiac disease from lovastatin, which was life-threatening for patients having class IV cardiomyopathy before lovastatin or after taking lovastatin. Oral administration of CoQ10 increased blood levels of CoQ10 and was generally accompanied by an improvement in cardiac function. Although a successful drug, lovastatin does have side effects, particularly including liver dysfunction, which presumably can be caused by the lovastatin-induced deficiency of CoQ10.

Adolescent↗

PubMed1989

The fate of the non-operated ear in otosclerosis.

Records of 300 consecutive patients who had only one ear operated on by stapedectomy and who received long-term followup were studied. These cases came from 3036 stapedectomy operations performed between January 1961 and April 1969. In general, the two ears behaved the same: if a "flat" sensorineural loss occurred in one ear, it was likely to develop in the other. Similarly, if one ear developed a high-tone loss, the other would do likewise. With the exception of acute fistula, there is no suggestion that the operation of stapedectomy predisposes an ear to late sensorineural problems. Patients with bone-conduction thresholds that are depressed at all frequencies when first examined should be advised that progressive sensorineural hearing loss may occur later in both ears. Accordingly, the benefit gained by stapedectomy may ultimately need to be supplemented by hearing aids. This study also revealed that a patient with clinical conductive otosclerosis in only one ear at first presentation had only a 50% chance of long-term benefit from stapedectomy.

Female↗

PubMed1987

Epitope insertion into the human hypoxanthine phosphoribosyltransferase protein and detection of the mutant protein by an anti-peptide antibody.

The translational stop codon TAA of the human hypoxanthine phosphoribosyltransferase (HPRT) cDNA has been changed to GAA by site-specific mutagenesis. This modification extends the open reading frame to a downstream stop codon and results in the addition of a unique negatively charged hexapeptide to the C terminus of human HPRT protein. The mutated cDNA was transferred into HPRT-deficient rodent cells by retroviral vector infection, and the expressed enzyme was found to be fully active. An antibody against a synthetic octapeptide corresponding to the mutated HPRT C terminus precipitated the HPRT protein specifically from cells infected with the mutant virus and not infected with the wild-type HPRT virus. The technique of inserting a novel epitope into a protein by site-directed mutagenesis should be generally applicable in studies of the regulation of gene expression in vitro and in vivo.

Epitopes↗

PubMed1978

Another look at Daggett's 1948 tympanoplasty.

It is important that we look critically at the results of conservative tympanoplasty in the presence of cholesteatoma. Lessons and observations taught many years ago by earlier otologists may give us valuable leads. A method of conservative surgery for chronic suppurative ear disease devised by Dr William Daggett in London in the late 1940s is described and evaluated in the light of current technical expertise.

Adult↗

PubMed1978