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Biomedical subjects

J C Morrison

Publications and source records attributed to J C Morrison.

At least 235 records · Page 13Linked to original sources
PubMed1989

Ultrastructural location of extracellular matrix components in the optic nerve head.

The distributions of laminin and collagen types I through V were determined in optic nerve heads of cynomolgus monkeys using colloidal gold immunoelectron microscopy. Collagen types I and III localized to striated collagen fibrils in arterial walls throughout the optic nerve head and to fibrils comprising the core of the lamina cribrosa beams and optic nerve septa. Collagen type IV and laminin localized to basement membranes of all blood vessels and to basement membranes of astrocytes that lie between the laminar beams and line the optic nerve septa and pia mater. Collagen type V was detected both in striated collagen fibrils and in vascular and astrocyte basement membranes. These results provide a detailed understanding of the optic nerve head extracellular matrix distribution and illustrate a sensitive method for future study of its role in glaucomatous optic nerve damage.

Animals↗
PubMed1989

Structural proteins of the neonatal and adult lamina cribrosa.

Optic nerve heads from three premature infants and six adults were studied immunohistochemically to compare the extracellular proteins in the lamina cribrosa of young and old human eyes. In both age groups, antibodies to the basement membrane components laminin and collagen type IV were associated with blood vessels and laminar beam margins. In the adult eyes, interstitial collagen types I and III were heavily distributed within the laminar beams. Antibodies to fibrillin, the microfibrillar portion of elastin, labeled discrete, heavy bands oriented longitudinally within these beams. The beams of the neonatal lamina cribrosa contained much less interstitial collagen, with a predominance of collagen type III. Neonatal elastic tissue bands were less numerous and distinct within the laminar beams. These biochemical differences between the young and old lamina cribrosa may, in part, explain different clinical behaviors of the optic nerve head in congenital and adult glaucoma.

Aged↗
PubMed1989

Use of prostaglandin E2 vaginal suppositories in third-trimester fetal demise.

A retrospective analysis of eight cases of third-trimester fetal demise managed with prostaglandin E2 vaginal suppositories (PGE2) is presented. Management included laminaria insertion prior to induction and an initial lower dosage of PGE2. No cases of uterine rupture or cervicovaginal lacerations were encountered. A summary of the literature as it relates to PGE2 vaginal suppository use in third-trimester fetal demise is included.

Adolescent↗
PubMed1989

Cost effectiveness of ambulatory uterine activity monitoring.

A cost analysis is presented comparing 34 patients who received uterine activity monitoring versus 33 patients who attempted to detect uterine activity by palpation. All patients were at high risk for preterm delivery and were given the same educational information and prenatal care regarding signs and symptoms of preterm labor. The results revealed an increase in newborn days (640) and cost to those patients who were in the self-palpation group ($13,364) compared to monitored parturients (268 days and $8,633). The difference was attributed to neonatal morbidity from an increased number of preterm deliveries greater than 26 weeks but less than 37 weeks (P = 0.04). The increase in NICU days was significant (P = 0.03). No difference in normal newborn costs for infants delivered after greater than 33 weeks could be detected between the two groups, but morbidity was increased among control infants delivering between 34 and 36 weeks. Uterine activity monitoring to prevent preterm birth appears to be medically effective and reduces cost.

Cost-Benefit Analysis↗
PubMed1989

Prostaglandin E2 induction of abortion and fetal demise.

Prostaglandin E2 (PGE2) suppositories have been shown to be active contractile agents and are effective in uterine evacuation for mid-trimester abortion or fetal demise. In this study, 85 patients were treated with vaginal PGE2 suppositories. When laminaria were used in patients with closed cervices, and compared to those who had minimal cervical dilatation, there was no difference in the time from induction to expulsion. Ninety-three percent of the 85 patients aborted successfully within 24 h. In each of the seven "failures", three or less suppositories were used prior to a dilatation and evacuation procedure. In this study, 81% of the abortions were complete, and in one-third of the remaining patients dilatation and curettage was performed just after delivery of the fetus. The incidence of minor side-effects ranged from 12 to 21%, and there were no major complications. It is concluded that the use of vaginal prostaglandin E2 suppositories for induction of mid-trimester abortion or fetal demise in the third trimester is safe and effective.

Abortion, Eugenic↗
PubMed1989

Pharmacokinetics of meperidine in pregnancy.

The disposition of meperidine was studied in 11 term pregnant humans after the administration of a single 50 mg intravenous dose of meperidine through 48 h post-injection. Half-lives of the rapid and terminal elimination phases were calculated as 2.3 and 13.3 h, respectively. These values are much greater than previously reported half-lives which were based on data collected over less than 8 h after injection. An accurate value for t1/2 beta may be particularly important in sequential dosing of analgesic medication. These pharmacokinetic constants calculated on data collected through 48 h in this study may have important clinical correlates.

Female↗
PubMed1989

Adjunctive glaucoma therapy. A comparison of apraclonidine to dipivefrin when added to timolol maleate.

The authors compared the additive intraocular pressure (IOP)-lowering effects of two different topical medications, apraclonidine hydrochloride and dipivefrin hydrochloride, when used in conjunction with timolol maleate. Eighteen patients with elevated IOPs entered a randomized, double-masked, cross-over study. Each used apraclonidine 1.0%, dipivefrin 0.1%, or placebo, twice daily for 3 weeks each, in addition to timolol 0.5% twice daily. Only apraclonidine produced a significant additional IOP lowering over timolol treatment alone at all time intervals (P less than 0.001). Its additive effect was significantly greater than that seen with dipivefrin at all time intervals (P less than 0.01), with the exception of day 22 (P = 0.061). No significant change in pulse rate or blood pressure was seen during apraclonidine administration. Apraclonidine may be a useful adjunctive agent in patients with poorly controlled glaucoma.

Adult↗
PubMed1989

Perinatal aspects of abdominal surgery for nonobstetric disease.

Surgical interventions for nonobstetric reasons during pregnancy are reported to occur in 0.2% to 2.2% of all gestations with obvious perinatal implications. In this retrospective study, 57 parturients were identified who underwent nonobstetric abdominal surgery. Thirty-one patients underwent exploratory celiotomy for suspected appendicitis, 16 for adnexal disease other than ectopic pregnancy, six for cholecystectomy, three for intestinal disorders, and one with a pheochromocytoma. Alterations in disease expression are related to the severity of the disease and advancing gestational age, being more important in cases of appendicitis. Preterm labor reflecting fetal morbidity relates to the presence of peritonitis and then only during the third trimester. In this retrospective study, tocolysis with intravenous magnesium sulfate had an uncertain effect on the incidence of preterm delivery. Prospective studies will be required to assess the indications and limitations of tocolysis for nonobstetric abdominal surgical conditions.

Abdomen↗
PubMed1989

Utilization of hydralazine or alpha-methyldopa for the management of early puerperal hypertension.

Despite the importance of pregnancy-induced hypertension (PIH), there are few published investigations of therapeutic approaches for the postpartum management of such patients. Twenty-six gravida patients with PIH were prospectively studied during the first 24 hours after delivery while receiving intravenous magnesium sulfate. Each study subject was randomly assigned to a group also systemically administered either hydralazine or methyldopa. During the study interval, hourly measurements of blood pressure, pulse, fluid intake, and urine output were recorded. Hydralazine was found to be superior in its ability to effect more rapidly a lower mean arterial blood pressure. No significant differences in urine output or time until onset of diuresis were noted among treatment groups. No serious side effects were encountered with the use of either antihypertensive agent. Based on these preliminary findings, it appears that hydralazine is the less costly and more effective medication to lower mean arterial blood pressure in the immediate postpartum period.

Blood Pressure↗
PubMed1989

Pregnant women with prosthetic heart valves.

Pregnant women with prosthetic heart valves present the same myriad of problems and challenges inherent in other patients with severe cardiac disease. Care for these patients should involve counseling to determine the advisability of attempting or continuing pregnancy. Combined team care with several specialists is necessary for the optimal management of these patients. Family planning is very important for these patients.

Anticoagulants↗
PubMed1989

Incarceration of the retroverted gravid uterus: report of four patients managed with uterine reduction.

Incarceration of the retroverted gravid uterus may have an adverse effect on pregnancy. To evaluate these effects, we reviewed obstetric records to identify parturients with the diagnosis of incarceration of the retroverted uterus during the years 1977 to 1987. Four such patients were identified by this retrospective review, for a calculated incidence in our primary population (patients not referred for evaluation who also received prenatal care at only one hospital) of one case per 10,384 live births. The incarceration was successfully reduced in all four patients without surgical intervention, and all had a normal infant of appropriate weight at term.

Diagnosis, Differential↗
PubMed1989

The impact of ambulatory glycemic control on the insulin-dependent diabetic gravida.

The pursuit of maternal euglycemia is the cornerstone of contemporary perinatal management of the insulin-requiring diabetic gravida and its achievement has been associated with reduced perinatal morbidity and mortality. The maternal and perinatal results of a pregnancy management protocol for insulin-requiring diabetic gravidas which emphasizes rigorous glucose control via ambulatory patient utilization of reflectance meter determinations of fasting and two-hour postprandial blood glucose is summarized in this report. The authors describe the excellent maternal and neonatal outcomes achieved with this protocol, and emphasize the efficacy of this ambulatory approach to the treatment of insulin-dependent diabetic pregnancies.

Ambulatory Care↗
PubMed1989

Cervical pregnancy managed without hysterectomy. A case report.

A woman with a cervical pregnancy was treated without a hysterectomy. Hemorrhage from the implantation site was controlled by placement of a Foley catheter balloon in the cervix. Placement and inflation of a Foley catheter balloon in the cervix after cervical dilation and curettage appears to be a simple and effective means of managing postoperative hemorrhage secondary to cervical pregnancy.

Adult↗
PubMed1989

Group B streptococcal sepsis and death in utero following funipuncture.

The technique of umbilical cord puncture for diagnosis and therapy, which has been shown to be feasible and relatively safe for both mother and fetus, is being used increasingly. The fetal loss rate with this technique has been estimated to be approximately 1%. A case is presented of fetal death from group B beta-streptococcal sepsis after funipuncture, the first report of this complication.

Adult↗
PubMed1989

"Outlier" intraocular pressure readings: valid or invalid for statistical analysis?

Wide variations in the response to intraocular (IOP)-lowering medications may be due to the normal response of the subjects or to variables unrelated to the effect of medication, eg, noncompliance or recording errors. We used data from a previous study of medications designed to lower IOP to investigate the influence of readings showing an unusually large increase in IOP from baseline on the statistical analysis and conclusions. These readings, which could have been due to variables unrelated to the effect of medication, were defined as "outliers" by a statistical method. A statistically insignificant difference between two IOP-lowering medications became significant on excluding two subjects with outlier IOP readings. We explain how reporting results obtained with and without including outliers in the analysis may provide clinicians with more complete information.

Analysis of Variance↗
PubMed1989

Lecithin:sphingomyelin ratio in the amniotic fluid of male and female fetuses.

The effect of fetal sex on the amniotic fluid lecithin:sphingomyelin (L:S) ratio was determined with a prospective, randomized, double-blind study designed to evaluate the effect of antenatal steroid administration on the incidence of neonatal respiratory distress syndrome. The immature L:S ratios of 183 single births to nondiabetic women were analyzed. L:S ratios increased with increasing gestational age. Regression lines of L:S versus gestational age suggested that male infants' L:S ratios were lower than females', although the differences were not statistically significant.

Amniotic Fluid↗
PubMed1989

Conservative management of Cushing's syndrome in pregnancy. A case report.

A woman with clinical and laboratory findings of Cushing's syndrome was managed during pregnancy without the use of surgery or drugs to lower her serum cortisol. A good maternal and infant outcome was achieved with conservative measures, and surgical removal of an adrenal adenoma was delayed until the postpartum period.

Adenoma↗