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Biomedical subjects

J C Morrison

Publications and source records attributed to J C Morrison.

At least 343 records · Page 19Linked to original sources
PubMed1980

Sickle hemoglobin and the gravid patient: a management controversy.

It is evident that patients with sickle cell disease are now in an era when they can safely complete a pregnancy with a reasonable expectation of a good outcome for both the mother and baby. Although there are vast disagreements as to which techniques (both diagnostic and therapeutic) to employ, the use of individualized methods in various geographic areas will yield the best result. To conclusively answer the questions raised in this article, a large multi-center collaborative study must be performed. If randomized treatment regimens of "transfusion versus no transfusion" were carried out in such a study, the true risk of both approaches could be assessed. Moreover, with adequate follow-up studies many of the risks of each type of treatment could be evaluated. Only through such a large study will these controversies be resolved.

Adult↗
PubMed1979

Primary dysmenorrhea treated with indomethacin.

Primary dysmenorrhea is a difficult entity to treat, and therapy is usually directed at relieving symptoms. There is some indication that this disorder is caused by an increase in prostaglandin F2alpha. Therefore, logically the treatment may include antiprostaglandin agents. We have studied 32 women with the diagnosis of primary dysmenorrhea in a randomized double-blind fashion using a placebo and indomethacin. Both agents were taken three times a day over four cycles, and therapy was begun two days before the usual onset of pelvic pain. Only two of 16 patients in the placebo group were significantly improved in the four-month treatment cycles while all 16 in the treatment group showed some improvement, 11 having cessation of pain. In the six months following the study period, all patients were given indomethacin. The original treatment group did not change significantly. However, all in the placebo group when switched to indomethacin had some relief, 12 of the 16 showing complete cessation of pain. Gastric irritation was the main side effect and was present in 18% of the treatment group and 12% in the placebo group. Indomethacin appears to effectively relieve primary dysmenorrhea and does not appear to be associated with a high incidence of side effects.

Adolescent↗
PubMed1978

Use of partial exchange transfusion preoperatively in patients with sickle cell hemoglobinopathies.

Sickle cell anemia and other severe sickle cell disorders (hemoglobin SC and hemoglobin S-thalassemia) are known to complicate surgical procedures in susceptible patients. Although transfusions have been used preoperatively to increase the packed cell volume, we have recently used the method of partial exchange transfusion in the treatment of patients with these disorders in the preoperative period. Forty-two patients with significant sickle cell hemoglobinopathies underwent operative procedures on various surgical services. The goal was to obtain a hemoglobin A percentage of 40 or above in each case, and this required 480 to 1,150 c.c. of buffy coat poor washed red cells (mean 820 c.c.). The number of complications in the intraoperative and postoperative period in this study was compared to those found in the literature. There was a significant decrease in morbidity and mortality rates noted with the use of these transfusions. There appeared to be a great advantage on a cost-benefit ratio, as well as an improvement in the physiologic state of the patient. Although the results of this study show significant improvement over previous investigations, there are many facets unknown concerning the use of this modality under these and other conditions. Therefore, further investigation of this method and restriction of the method of Level III referral centers is advocated until enough patients have been studied to assess the long- and short-term complications of the procedure.

Adolescent↗
PubMed1978

SQ 20,881: effect on eclamptic--pre-eclamptic women with postpartum hypertension.

The renin-angiotensin system has been implicated in the genesis of pre-eclampsia. To avoid fetal toxicity, five women were studied who developed hypertension, proteinuria, and edema in the last trimester of pregnancy and whose BP elevation persisted immediately postpartum. At about 6 hours after delivery the CE enzyme inhibitor (SQ 20,881) was given in incremental doses ranging from 0.25 to 3.0 mg. per kilogram intravenously, before and after diuresis with furosemide, 40 mg. intravenously. BP was measure every 2 minutes and PRA and angiotensin II concentration before treatment, 30 minutes after 0.25 to 0.30 mg. per kilogram, and 30 minutes after 2.0 to 3.0 mg. per kilogram. Echocardiographic assessment of CI and PVR was performed before treatment and after a maximum dose in three patients. Before diuresis, CE blockade had no effect on heart rate, BP, CI, PVR, or PRA, regardless of whether the patient was in positive or negative fluid balance or was sodium loaded or restricted over the preceding 24 hours. Angiotensin II fell by 77 and 10 per cent, respectively, after 0.25 mg. per kilogram was given to two patients, but rose slightly in the other three patients, then fell an average of 46 per cent after 1.0 to 3.0 mg. per kilogram were given. After diuresis, 1.0 mg. per kilogram resulted in a 24 per cent fall in BP which persisted for 3 hours in two patients and a 14 per cent fall which lasted for 30 minutes after 1.0 or 3.0 mg. per kilogram in a third patient. It is concluded that the BP elevation which persists after delivery in certain patients with pre-eclampsia is not angiotensin II dependent.

Adolescent↗
PubMed1978

Injection of corticosteroids into mother to prevent neonatal respiratory distress syndrome.

In this study, 500 mg. of hydrocortisone were injected intravenously into 126 women every 12 hours for four doses in a double-blind, randomized fashion. These 126 subjects were at risk for delivery of a premature infant because of premature labor of fetomaternal disease necessitating intervention. There were 67 patients in the treatment group and 59 in the placebo group. All patients had immature lecithin/sphingomyelin ratios and/or were at less than 34 weeks' gestation. From these data, it appeared that there was a significant decrease in respiratory distress syndrome when the treatment group was compared to the placebo group. The neonatal survival rates also were improved significantly by steroid treatment. There was no demonstrable adverse steroid effect in mothers of fetuses in the long-term or short-term follow-up period, although a significant number of patients were lost to follow-up and the methodology of infant evaluation was imprecise. It would appear from these data that the injection of steroids is beneficial in mothers at risk of being delivered of premature infants. However, many questions remain to be answered before this method can be relied upon as therapy for women with premature labor.

Adolescent↗
PubMed1977

Separation of isoacceptor cysteine transfer ribonucleic acids of bakers' yeasts.

Isoacceptor species of certain amino acid-specific transfer ribonucleic acids (tRNAs) were fractionated by gel permeation chromatography using Sephadex G-100. The separation is attributed to the 20% ethanol-1% NaCl solvent and to the characteristics of Sephadex. Isoacceptor tRNAs specific for cysteine, arginine, phenylalanine, and histidine were recovered from commercial tRNA of yeast by this method. Highly purified cysteine-specific tRNA, obtained by a method which would not be expected to separate isoacceptor molecules when fractionated by this procedure, was shown to contain two cysteine isoacceptor tRNAs.

Amino Acyl-tRNA Synthetases↗
PubMed1977

The lecithin/sphingomyelin ratio in cases associated with fetomaternal disease.

The efficacy of correlating the L/S ratio in the amniotic fluid with fetal lung maturity has been substantiated in normal pregnancies. In gestations complicated by fetomaternal diseases, however, the assay is less reliable. This study involves 555 pregnancies in which there was a significant maternal, fetal, or placental disorder. The L/S ratio was related to fetal respiratory maturity as measured by Dubowitz criteria and the occurrence of RDS. The results show that pre-eclampsia, chronic hypertension, diabetes (Class D, E, F), significant cardiovascular disease, severe hemoglobinopathies, various congenital anomalies, chronic placental insufficiency, and prolonged ruptured membranes accelerated the L/S ration. Conversely, mild diabetes (Class B, C), intrinsic renal disease, hepatitis, collagen disease, hydrops fetalis, syphilis, and toxoplasmosis were associated with a delay in the L/S ratio. A significant increase in erroneous responses was noted in these patients when the L/S ratio was correlated to infant maturity and to the incidence of RDS. Possible mechanisms for these findings are discussed.

Amniotic Fluid↗
PubMed1977

Mechanism for the incorporation of S-(1,2,3,4-tetrahydro-2-hydroxy-1-naphthyl)-L-cysteine into protein.

Evidence is presented which indicates that S-(1,2,3,4-tetrahydro-2-hydroxy-1-naphthyl)-L-cysteine (THN-cysteine), formed by the reaction of 1,2-epoxy-THN with cysteine, can be incorporated into protein; The position of incorporation of THN-cysteine into protein would depend on whether the epoxide of THN reacts with cysteinyl-tRNACyS or with cysteine. In both cases, the mechanism of incorporation of THN-cysteine into protein is the same as for the natural amino acids. For example, the incorporation of THN-cysteinyl-tRNACyS is stimulated by Poly-UG, the code for tRNACyS, and would be expected to be substituted for cysteine in protein being synthesized, whereas THN-cysteine not previously esterified to tRNA is activated by the isoleucyl- and valyl-RNA synthetases, and its incorporation is stimulated by Poly-AU and Poly-UG, respectively. Consequently, in this case, THN-cysteine would substitute for isoleucine and valine during protein synthesis.

Cysteine↗
PubMed1977

Postnatal development of binding of streptococci and lipoteichoic acid by oral mucosal cells of humans.

The colonization of mucosal cells in the oral cavity of newborn infants was studied at various intervals after birth in an attempt to define the nature of the epithelial binding sites for group A streptococci and their lipoteichoic acid (LTA). Stained smears of buccal mucosal cells showed that the average number of naturally acquired bacteria/cell was zero to one in infants less than one day old, one to four in infants one day old, and 11-19 in infants two days old. Samples of the same mucosal cells were incubated with group A streptococci, and the average number of streptococci bound per cell was 10-31 in infants less than one day old, 33-62 in one-day-old infants, and 75-100 in two-day-old infants. Experiments that were repeated with group B streptococci type III produced similar results. LTA, the substance that mediates the binding of streptococci to epithelial cells, was similarly bound by fewer buccal mucosal cells obtained within 6 hr of birth than cells obtained during the next 48 hr. Streptococcal and LTA binding reached adult levels between 48 and 72 hr after birth. No difference was shown in the streptococcal binding capacity of oral epithelial cell obtained from mothers at term and cells obtained from other normal adults. Preincubation of adult buccal cells with amniotic fluid did not decrease streptococcal binding. These studies demonstrated a scant capacity of the oral mucosal cells of neonates to bind LTA and streptococci and suggest that LTA-binding sites are developed or unmasked during the first few days after birth.

Adult↗
PubMed1977

Amniotic fluid tests for fetal maturity in normal and abnormal pregnancies.

The lecithin-sphingomyelin (L/S) ratio is acknowledged to be superior to most procedures for predictinf fetal lung maturity in normal pregnancy. In complicated gestations, however, errors have been reported. This study involves 686 normal gestations and 389 pregnancies complicated by fetomaternal diseases. The L/S ratio, creatinine level, and percent of fat-staining cells were measured in samples of amniotic fluid from these patients. The results showed good correlation of all three tests with fetal maturity as measured by weight, Dubowitz criteria, and incidence of respiratory distress syndrome in the normal patients. In the complicated pregnancies, however, the creatinine was unacceptable in up to 30% of the cases. The L/S ratio likewise decreased in accuracy for all parameters of fetal maturity measured. The Nile blue staining of the fetal cells appeared to be the most consistent technic in these cases. A fetal maturity battery comprised of these three assays and other methods of assessing fetal health is advocated in pregnancies complicated by certain disease states.

Amniocentesis↗
PubMed1977

Nile blue and fetal maturity. Further investigations.

The consistency of results using Nile blue staining of fetal cells in amniotic fluid to estimate fetal maturity has been demonstrated. Recently, evidence to support this method has been published from this laboratory. Several biochemical and technical factors were cited as important to the success of the method. This report deals with further testing of several Nile blue dyes (hydrochloride and sulfate) necessitated by changes in production and federal regulation of this compound. The results show Nile blue hydrochloride (HCl) to be the most superior dye regardless of color index. Buffered solutions (6.6) of Nile blue A (sulfate) improve its performance, but not to levels demonstrated by the HCl preparation. Storage at room temperature adversely affects each dye; however, the sulfate variety appears to be the most unreliable under these circumstances. For best results, it is recommended that Nile blue HCl be used and the solution (buffered or normal) be kept refrigerated.

Amniotic Fluid↗
PubMed1976

Metabolites of meperidine in the fetal and maternal serum.

Although meperidine appears to be the safest obstetric analgesic agent, it has been associated with infant respiratory depression in certain situations. It would appear that the incidence of fetal depression related to meperidine is dependent on the time of injection prior to delivery, the quantity of drug administered, and the rate of maternal metabolism of the analgesic. Previous work showed that meperidine is metabolized in the maternal system by one of three patterns. The present study demonstrates that the particular maternal serum pattern is characteristic for the individual, regardless of whether the patient is pregnant or not, and that the fetal depression, although usually mild, can be correlated with fetal pH data as well as Apgar scores. In addition, this study supports indirectly the contention that metabolites of meperidine rather than the parent compound cause fetal depression. It would appear, therefore, that in certain obstetric cases with a higher probability for infant depression, other analgesic agents might be considered, especially if the serum pattern indicates meperidine is being metabolized.

Apgar Score↗
PubMed1976

Fluctuation of fetal hemoglobin in sickle-cell anemia.

A reduction of morbidity and mortality rates in homozygous sickle-cell patients was found in those with high fetal hemoglobin (HbF) levels. This factor would lead one to believe that an adequate amount of this substance would be protective to a patient with this hemoglobinopathy. This study utilizing pregnant and nongravid females, as well as males, followed for long periods of time indicates that the HbF level fluctuates with crisis. Some patients had low HbF levels with many crises and others had high amounts of HbF with no crises. However, many patients with high levels on one occasion demonstrated a decrease in HbF levels when crisis occurred. More importantly, no patient had high levels of HbF during a crisis although the amount was elevated before and after the episodes. The possible explanation and ramifications of this finding are discussed.

Anemia, Sickle Cell↗