Cytomegalic virus disease in pregnancy.

A case report is presented in which cytomegalic virus inclusion bodies were demonstrated in twin placentas and in both infants. This is the fourth such report in the English language literature. The case also demonstrated interlocking of the fetal heads requiring decapitation of the dead twin in order to deliver the surviving twin. The survivor showed gross stigmas of cytomegalic viral disease.

Patient-controlled analgesia for post-cesarean section pain.

Recent reports have suggested that patient-controlled analgesia is an effective means of narcotic administration in postoperative patients. This prospective investigation was undertaken to determine the efficacy and safety of patient-controlled anesthesia infusion after cesarean section. During a recent ten-month period, 130 patients were assigned randomly to receive meperidine by pump or intramuscular injection. Meperidine consumption using the device varied widely to meet individual needs. Overdosage and drug dependence were not encountered with the prescribed drug concentrations. The patient-controlled analgesia method provided less sedation and more immediate pain relief without the need for painful injections. The additional cost of renting the infuser device was offset by combined patient and nursing satisfaction. We conclude that patient-controlled infusion of meperidine is safe and effective in satisfying individual patient needs after cesarean section.

Randomized comparison of meperidine and fentanyl during labor.

This randomized investigation compared the efficacy of the conventional narcotic, meperidine, and a more potent and short-acting analgesic, fentanyl, during labor. One hundred five women with uncomplicated term pregnancies in active labor were randomly assigned to receive either intravenous fentanyl (50-100 micrograms every hour) or meperidine (25-50 mg every 2-3 hours) in a non-blinded manner. The analgesics were rated equivalent in efficacy. Maternal nausea, vomiting, and prolonged sedation occurred more frequently in the meperidine group. Naloxone use was significantly less in fentanyl- than in meperidine-exposed infants (one of 49 versus seven of 56; P less than .05). Neuroadaptive testing at approximately 2 hours and 24 hours postnatally revealed similar averaged scores in the two groups. Using the described intravenous dosing schedule, fentanyl was preferable to meperidine during labor because there was no prolonged maternal sedation or vomiting necessitating therapy and the requirement for neonatal naloxone was reduced.

Use-effectiveness and analysis of satisfaction levels with the Billings Ovulation Method: two-year pilot study.

A 2-year study of 135 women using the Billings Ovulation Method as their method of family planning is reported. There were 1381 exposure cycles during the 1st year and 580 during the 2nd year. The total conception rates were 1.303 for the 1st year and 1.896 for the 2nd year. If one subtract the user failures from these rates, the biologic failure rates are 0.072 for the 1st year and 0.517 for the 2nd year. The continuation rate is 51.8%. An analysis of satisfaction levels is presented with a discussion of possible underlying emotional factors.

Sampling considerations for multilevel crossing analysis.

This paper examines the amplitude fluctuations of band-limited functions with bounded zeroth absolute moments, and the problems associated with estimating the level crossing profiles of these functions. Level crossings have received increased attention as features for pattern recognition because of their capability to provide information related to both amplitude and frequency behavior. A detailed analysis of the average rate of change of band-limited functions is presented, including a derivation of the least upper bound on functions for which the zeroth absolute moments of the functions are bounded. The average rate of change of a function over an interval in which one endpoint of the interval is an extremum of the function is similarly bounded and used to establish a sampling rate which guarantees that between successive samples of a band-limited function with bounded zeroth absolute moment the function itself does not deviate from the amplitude interval defined by the samples by more than some predefined amplitude change. Based on these results, a theorem is developed which defines the sampling rate required to ensure that, in the estimation of level crossing profiles, no more than 2m (m >> 1) level crossings of m levels are missed per extremum of the sampled function. It is shown that the sampling rate defined by this theorem reduces to the well-known Nyquist rate for the special case of zero crossing analysis.

Dihydroouabain, a reversible inhibitor of the sodium pump in frog skin.

In many studies of the sodium pump in epithelia, a readily reversible analog of ouabain would be most useful. This would enable studies of pump activity to be made under control and experimental conditions on the same tissue. Of three compounds examined on the basolateral membrane of the isolated epithelia of frog skin, dihydroouabain (DHO) had characteristics very similar to ouabain except that it was apparently much more reversible. DHO (1 mmol/l) inhibited short circuit current (Isc) and transepithelial Na flux (JNa13) in a fashion similar to ouabain. Isc was inhibited from 17.0 +/- 2.5 to 10.2 +/- 1.0 microA/cm2 in 2-4 min while JNa13 was decreased from 16.8 +/- 1.9 to 4.7 +/- 0.8 microA/cm2 in the same time interval. After 60 min of washout, Isc and JNa13 recovered to about 70% of control values and were nearly equal. In another set of experiments, the washout of DHO and ouabain were compared directly on the same tissue. Sodium flux recovered four times faster after removal of DHO when compared to ouabain. Pretreatment of tissues with DHO prior to ouabain greatly increased the rate of Na flux recovery after washout of both drugs suggesting that DHO competes for ouabain sites. These data suggest that DHO can be used as a reversible analog for ouabain in studies of the Na pump in frog skin.

Net basolateral potassium flux and short-circuit current in ouabain-treated frog skin.

A new technique has been developed to correlate K loss from cells (JK) across the basolateral membrane into a K-free ouabain Ringer solution and short-circuit current (Isc) for a model Na-transporting epithelium, the frog skin. Distinct differences were observed when the tissue was bathed in sulfate or chloride Ringer. In sulfate Ringer, K-free ouabain treatment caused both JK and Isc to decline in a nearly parallel fashion with time. JK-Isc was approximately 1 microA/cm2. In sulfate Ringer, isoproterenol caused parallel increases, whereas amiloride (apical side) caused parallel decreases in JK and Isc. In chloride Ringer, K-free ouabain treatment caused Isc to decline at a slightly faster rate than JK.JK-Isc was approximately 8 microA/cm2. Bumetanide decreased JK with very little effect on Isc. Barium caused small parallel changes in both Isc and JK. Amiloride decreased Isc with very little effect on JK. These experiments show that after ouabain treatment changes in JK from the cells across the basolateral membrane can largely account for changes in Isc. However, JK also occurs via neutral mechanisms and perhaps from cells not related to the transport pathway, demonstrating that there is not always a tight coupling of K loss at the basolateral membrane with Na entry across the apical membrane.

Fluctuating asymmetry for specific bristle characters in notch mutants of Drosophila melanogaster.

Asymmetry has been used as a measure of developmental stability for bilaterally symmetrical organisms. Most studies have failed to partition the genetic and environmental contributions to the asymmetry phenotype due to the limitations of the systems used or the shortcomings in experimental design. The Notch mutants of Drosophila melanogaster were used to study the genetic contribution to asymmetry for six different bristle characters. Asymmetry response was character specific for the mutants examined. For Nspl, N(Co), N264-47, Ax71d, Ax9B2, AxE2, 1(1)N(B) and nd2 significant asymmetry responses, relative to wildtype Canton-S, were observed for some characters. N60g11 and nd1 did not exhibit significant asymmetry for any of the characters examined. All of the mutants except N60g11 and nd1 showed thoracic bristle asymmetry. However, when asymmetry scores were pooled over the five bristle characters which individually exhibited fluctuating asymmetry, no significant differences were found between any genotypes. Therefore pooling asymmetry values across characters obscures the significant character specific asymmetry values observed. Thus caution is necessary when using the asymmetry phenotype of specific characters to draw organism wide conclusions about developmental stability.

Failed induction of labor despite sequential prostaglandin E2 therapy.

Preinduction cervical ripening with prostaglandin E2 (PGE2) is useful in minimizing the chances for a failed induction of labor. The lack of sufficient cervical dilation despite PGE2 and oxytocin therapy is uncommon. This investigation was undertaken to determine reasons for any failed inductions in pregnancies with pregel Bishop scores 4 or lower and requiring delivery within 24 hours. Fifteen (12.1%) of 124 eligible patients had failed inductions despite two 2.5 mg intravaginal doses. A finding in all the failures was a very unfavorable cervix (pregel Bishop score 0 to 2). The need for preterm delivery (33 to 37 weeks) was a common finding in the presence of a very unfavorable cervix. The data suggest that complicated pregnancies requiring delivery within 24 hours and failing to respond to sequential PGE2 therapy in the presence of a very unfavorable cervix may benefit from cesarean section without a prolonged induction.

A simplified method of obtaining umbilical cord blood for pH using a heparinized vacutainer versus heparinized syringe.

Two experimental methods for collecting cord blood for acid-base analysis using green top vacutainer tubes were compared with a standard method using heparinized syringes. Paired samples from 30 newborn infants were collected using one of the vacutainer methods and the standard heparinized syringe method. No significant differences in pH, pCO2, base deficit, or pO2 were noted when comparing the two vacutainer methods with the standard syringe method. Both vacutainer methods were substantially easier to use than the heparinized syringe method. A green top vacutainer may be used to obtain an accurate cord blood sample for assessment of an infant's acid-base status at birth, and to aid the neonatologist as an indicator of intrapartum asphyxia.

Renal adaptation to low-phosphate diet in diabetic rats.

Insulin stimulates the Na(+)-Pi cotransport system in the brush-border membrane (BBM) of the renal proximal tubule, and an acute decrease in plasma insulin leads to a decrease in renal reabsorption of Pi. It has been proposed that insulin may play a role in the rapid renal adaptation to dietary deprivation of Pi. This hypothesis was tested using rats with low plasma insulin due to streptozotocin-induced diabetes. Both control and diabetic rats were housed in metabolic cages and fed either a normal Pi diet or a low Pi diet for 3 days. At the end of the third day, BBM vesicles were prepared from renal cortex and Na(+)-Pi cotransport was measured. At the whole kidney level, diabetic rats showed a normal adaptive response. There was a prompt and marked decrease in urinary Pi excretion when the rats ate a low Pi diet. At the BBM level, however, the adaptive response was absent. There was no increase in Na(+)-Pi cotransport in diabetic rats fed low Pi diet. Treatment of diabetic rats with exogenous insulin before feeding low Pi diet restored the adaptive increase in Pi transport by BBM. Insulin appears to be required for the adaptation of proximal tubule Pi transport to low Pi diet. In the absence of this adaptation in proximal tubule BBM, a compensatory response in the kidney may produce an increase in Pi reabsorption in later segments of the nephron.

Clinical signs of normal plasma volume expansion during pregnancy.

A majority of cases of pregnancy complications are associated with a relative maternal hypovolemia. The records of 200 pregnant women who had had plasma volume determinations were reviewed in hopes of finding indicators of relative maternal hypovolemia other than the pregnancy complication itself. The signs of relative hypovolemia in pregnant women include those of decreased uterine growth, absence of a maternal systolic flow murmur, and absence of significant dependent ankle edema. Laboratory tests indicative of maternal hypovolemia include failure to develop a decline in maternal hematocrit, serum blood urea nitrogen/creatinine ratio greater than 15, a decreased creatinine clearance, abnormal platelet function, elevated serum glutamic oxaloacetic transaminase, ultrasonic evidence of oligohydramnios and/or decreased maternal heart size, and absence of hypervolemia on chest x-ray film. These findings and tests are only relative indicators of maternal hypovolemia, and it is suggested that, for an accurate defining of pregnant women who are at risk, the actual plasma volume determination has to be performed frequently in the pregnant population.

Elevated static pressure and pregnancy well-being.

Static pressure is defined as the pressure existing at all points in the circulation when the heart is stopped and is a determinant of cardiac output and blood pressure. By using the proposed relationship that static pressure = cardiac output X "resistance to venous return," estimates were made of peripheral static pressure in pregnant women. Measurements of cardiac output and venous resistance were accomplished with indirect plethysmographic techniques. Approximately 65% of pregnant women with complications had elevated values for their estimated peripheral static pressure. It is proposed that estimation of peripheral static pressure has both diagnostic and therapeutic applications in women with complications of pregnancy.