Biomedical subjects
Publications and source records attributed to T L Gross.
Widespread cutaneous papules in a yearling Standardbred filly were attributed by light and electron microscopic examination to molluscum contagiosum. Concomitant granulomatous enteritis, suspected clinically due to protein-losing enteropathy, was verified histopathologically. An associated altered altered immune response is suggested as the reason for the widespread poxvirus infection.
The risk of recurrent small for gestational age birth, as well as maternal and fetal-neonatal characteristics associated with recurrence, was examined in 174 mothers of consecutively delivered small for gestational age infants followed through an additional 240 livebirths. There was a twofold and fourfold increase in the risk for small for gestational age birth after one and two small for gestational age births, respectively. Although an intervening average for gestational age birth decreased the risk of recurrence, these women remained at increased risk over the general population. Given the history of a previous small for gestational age birth, perinatal risks and outcomes considered individually would not improve the prediction of recurrence. However, the significantly higher frequency of these variables, considered as a group, among mothers with recurrent small for gestational age birth suggests an association with underlying maternal disease, for example, chronic hypertension, substance use and abuse, more severe fetal-neonatal compromise, and recurrent small for gestational age birth. Recurrent small for gestational age birth should initiate a search for persistent, underlying maternal disease.
Cutaneous lesions of 36 collie dogs affected with dermatomyositis were reviewed. The most common histologic features were follicular atrophy and perifollicular inflammation in 30 dogs, which correlated with alopecia clinically. Other less common findings included formation of colloid bodies, basal cell vacuolation, and subepidermal vesiculation. Results indicated that the most diagnostic cutaneous histologic features of dermatomyositis may be follicular atrophy and inflammation.
Explore the source record for details and available documents.
Intravenous administration of ritodrine for tocolysis has been associated with maternal cardiovascular and metabolic changes. Studies with other tocolytic agents, such as isoxsuprine, have shown an increased neonatal morbidity among infants born soon after failure of such therapy. We examined the potential side effects of maternal intravenous ritodrine therapy in 58 neonates born within 12 h following discontinuation of maternal medication. 'Low dextrostix' was significantly greater in the ritodrine exposed neonates (p less than 0.05) than in the controls. It occurred within a mean 1.0 +/- 0.5 h following birth. The mean 1 min and 5 min Apgar scores, neonatal pH, bicarbonate levels, hypotension and neonatal mortality were comparable in the ritodrine-exposed and control groups of neonates. The occurrence of any of the neonatal morbidity variables, including 'low dextrostix' was not related either to the total dose of ritodrine used or to the interval between drug discontinuation and delivery. Administration of ritodrine by the standard protocol to stop preterm labor is not associated with any significant increase in neonatal morbidity.
Explore the source record for details and available documents.
Eighteen cats with miliary dermatitis were evaluated, using skin testing and histology. Sixteen cats had allergic skin disease (14 cats had positive skin-test reactions to flea antigen [two of which were also atopic], one was atopic only, and one was allergic to beef). In the two remaining cats, the cause of miliary dermatitis was not identified. Histologically, 17 of the cats had superficial eosinophilic dermatitis and epidermal spongiosis, crusting, and ulceration, which were compatible with an allergic cause. Four of these cats had concurrent eosinophilic plaques, which histologically resembled miliary lesions. This overlap of plaques with miliary lesions indicated that when plaques and miliary dermatitis are found concurrently, both lesions may be caused by the same allergens.
The purpose of this study was to add to the limited information available regarding the pharmacology of ritodrine in the peripartum period when treatment fails and labor is not inhibited. Plasma or urine samples from eight parturients and 13 infants were studied; in addition plasma samples at delivery were obtained from a total of 26 mothers and infants. All the mothers received ritodrine in the 24 hours before delivery. Plasma and urine ritodrine (free and conjugated) were determined with HPLC by electrochemical detection. In maternal plasma, an apparent rapid distribution phase with a t1/2 of 32 +/- 21 minutes was followed by a prolonged equilibrium phase with a t1/2 of 17 +/- 10 hours. Seventy-six percent of the ritodrine excreted by the mother was in the form of a conjugate. Ninety percent of the ritodrine excreted by the neonate was also excreted in the form of a conjugate.
A middle-aged, spayed female dog developed multiple cutaneous neoplasms that had clinical and histologic features of Bowen's disease in humans. Although lesions began in sun-exposed, glabrous skin, they progressed to hairy skin and to mucous membranes. Metastasis did not occur, although one lesion eventuated in local invasion of bone. The dog subsequently developed metastatic cutaneous myxosarcoma and euthanasia was requested by the owners.
There has been a relatively recent interest in alternative birthing techniques, including increased maternal mobility during labor. This literature review was pursued to evaluate the effect of upright maternal posture and ambulation on the first stage of labor. Although previous reviews frequently assume that maternal ambulation speeds labor progress, the data presented in this review are not conclusive as to whether the upright maternal posture or ambulation during the first stage of labor shortens labor length or improves fetal outcome. However, it is clear that ambulation in labor is not harmful either to the mother or fetus. In addition, many investigators have reported that mobility in labor results in greater maternal comfort and ability to tolerate labor and decreased use of anesthesia and analgesia. Thus, acceptance of mobility in labor by patients and staff is generally reported. This information can serve as a guide to clinical management. However, there is a need for further analysis of the effect of maternal ambulation during labor, and specific suggestions for research are presented.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Accurate prediction of fetal pulmonary maturity by means of a less invasive procedure than amniocentesis would be desirable. Sonographic diagnosis of a Grade III placenta has been reported to be an excellent predictor of fetal lung maturity. The standard classification of placental grading assigns grade according to the most advanced portion of the placenta. Using this classification, we studied 230 patients. In 80 pregnancies with Grade III placenta, three of the neonates developed respiratory distress syndrome. With reclassification of the placentas as immature, (no Grade III areas), intermediate, (only a portion of the placenta being Grade III), or mature, (Grade III placenta throughout), it was found that no neonatal hyaline membrane disease occurred in the 41 pregnancies with mature placentas, whereas 12% of the neonates in the immature group and 8% in the intermediate group developed hyaline membrane disease. These findings suggest that when sonographic examination of the placenta shows both Grade III and non-Grade III sections, there is still a risk for an immature amniotic fluid lecithin/sphingomyelin ratio and neonatal hyaline membrane disease. The placentas should be considered mature only when Grade III changes are present in all sections examined by ultrasound.
Amniostat-FLM is a recently developed rapid slide agglutination test for amniotic fluid phosphatidylglycerol. We compared phosphatidylglycerol quantitated by two-dimensional thin-layer chromatography with phosphatidylglycerol determined by Amniostat-FLM in 180 amniotic fluid samples. If any level of phosphatidylglycerol by thin-layer chromatography, including a trace, was considered positive, then phosphatidylglycerol by thin-layer chromatography and Amniostat-FLM were concordant in 171 of 180 samples (95%). Both were positive in 123 and both negative in 48 samples. The nine amniotic fluid samples with discrepant results were as follows: Five negative Amniostat-FLM results were associated with trace phosphatidylglycerol by thin-layer chromatography (1% to 2% of total phospholipids), one negative Amniostat-FLM result was associated with 3% phosphatidylglycerol by thin-layer chromatography, and three positive Amniostat-FLM results were associated with negative phosphatidylglycerol by thin-layer chromatography results. There were 14 samples with trace phosphatidylglycerol by thin-layer chromatography; of these, there were nine positive and five negative Amniostat-FLM results. If greater than 2% phosphatidylglycerol by thin-layer chromatography was considered positive, concordance between the two tests was 93% (167 of 180). From these samples, 119 infants were delivered within 72 hours of amniocentesis. There were 100 positive Amniostat-FLM results and all were associated with the absence of respiratory distress syndrome; of the 19 negative Amniostat-FLM results, five were associated with infants who developed respiratory distress syndrome. The present study confirms that Amniostat-FLM is a simple, rapid, and accurate test for determining the presence of phosphatidylglycerol in amniotic fluid.
The reported effects of alcohol on lung and brain phospholipid metabolism in adult animals have been numerous, but its effect on the fetal lung has not been examined. We investigated the effect of heavy maternal ethanol intake on fetal pulmonary maturation, as measured by the amniotic fluid phospholipids, lecithin and phosphatidylglycerol (PG). Mothers were screened at their first prenatal visit, and detailed drinking histories were taken. Amniotic fluid phospholipids were determined later in pregnancy for clinical purposes, and mothers with positive scores who admitted to drinking during the third trimester were compared to a control group. Amniotic fluid from mothers whose fetuses were exposed to ethanol late in pregnancy did not show the expected increase in lecithin/sphingomyelin and PG related to gestational age that was observed in nondrinking mothers. Canonical correlation of gestational age, late pregnancy drinking, and chronic alcohol problems with amniotic fluid L/S and PG jointly revealed that both gestational age and maternal drinking were significant determinants of fetal lung maturity (r = .39, P less than .05), with active maternal drinking being about one-third as important a determinant as gestational age. These findings could be explained by the known damage-inducing effect of ethanol on alveolar cell membranes or by the effects of ethanol on phospholipid metabolism.
Hypersensitivity to fleas was induced in flea-naive dogs by controlled challenge exposure to virgin fleas. By week 10 of the investigation, immediate (15 minute) and delayed (24-48 hours) responses could be elicited in the skin by flea bites. Histologically, the immediate response consisted of edema and eosinophils which sometimes overlapped with a delayed inflammatory response comprised of perivascular lymphocytes and fewer histiocytes. These inflammatory patterns correlated with type I or immediate, and type IV or cellular, allergic reactions. The combined immediate and delayed responses to fleas in the dog are as observed by other investigators in man and guinea pigs.
Ultrasound examination to measure the fetal biparietal diameter (BPD) and examine amniotic fluid for the presence or absence of free-floating particles was performed in 213 patients undergoing amniocenteses for maturity testing at term. A modified lecithin to sphingomyelin ratio (L/S) was performed on all samples. A BPD greater than or equal to 92 mm predicted 37 of 111 (33%) mature L/S ratios of nondiabetic pregnancies. The presence of free-floating particles predicted 48 of 138 (35%) mature L/S ratios of nondiabetics. Combined, a BPD greater than or equal to 92 mm and/or the presence of free-floating particles predicted 57 of 110 (52%) mature L/S ratios of nondiabetics. It is concluded that a BPD greater than or equal to 92 mm and the presence of free-floating particles are independent yet complimentary predictors of fetal lung maturity.
Previous studies using other beta-adrenergic drugs for tocolysis suggest that if treatment fails and the patient delivers shortly after the therapy is discontinued, there is a direct correlation between neonatal drug concentration and major neonatal complications. In the present study, the disposition of ritodrine was studied in 28 maternal-infant pairs in whom intravenous ritodrine had been administered for clinical indications. The fetal to maternal ratio of ritodrine was 1.17 +/- 0.48. The concentration of ritodrine in both maternal and umbilical vein was found to vary inversely with the length of time the drug was discontinued before delivery. A stepwise multilinear regression revealed that the maternal ritodrine dose in the 24 hours before delivery and the drug discontinuance to delivery interval were both independently related to umbilical vein ritodrine concentrations. When combined, the two variables explained 52% of the variance in umbilical vein ritodrine levels. The frequency of respiratory distress syndrome was increased in the neonates in whom umbilical vein ritodrine was greater than 10 ng/mL, compared with the groups with umbilical vein levels ranging from 3.0 to 10.0 ng/mL. However, neonates with the highest ritodrine concentration were also of lower gestational age (29.4 versus 33.5 weeks, P less than .05) and thus, had greater inherent risk of prematurity-related complications.