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Biomedical subjects

A C Cruz

Publications and source records attributed to A C Cruz.

At least 37 records · Page 2Linked to original sources
PubMed1991

Elastic-related fibers in the annular ligament of the stapes-oval window articulation. An electron microscopic and histochemical study in the rat and the rabbit.

The annular ligament that attaches the circumference of the base of the stapes to the margin of the oval window (fenestra vestibuli) was stained with selective methods for elastic system fibers and was also studied at the ultrastructural level after tannic acid-glutaraldehyde fixation. Although the annular ligament is devoid of elastic fibers, it is rich in elastic-related fibers (i.e. = oxytalan and elaunin fibers). Elaunin fibers predominate in the annular ligament itself and they are continuous with the oxytalan fibers which are embedded in the matrix of the articular cartilage.

Animals↗
PubMed1990

The "crowding effect" phenomenon in Ascaris lumbricoides.

Ascaris lumbricoides worm populations were studied from 150 Filipino children (0-14 years) dewormed with pyrantel pamoate (Combantrin) or oxantel-pyrantel pamoate (Quantrel). Populations were classified according to intensity of infection: very light, light, moderate or heavy. A total of 2072 adult worms were sexed (939 males and 1133 females) and weighed. Descriptive statistics on the weights obtained from each sex were derived and one-way ANOVA was performed to compare the mean weights among the 4 intensity classes. Linear regression analysis (individual worm weight versus total worm burden) was also employed to equalize the possible influence of host factors. Statistical analysis revealed that mean weights of both sexes were significantly different and decreased as worm burden increased. This strongly suggests that the "crowding effect" phenomenon may also apply to Ascaris lumbricoides, and not only to tapeworms, as reported in the literature.

Adolescent↗
PubMed1989

Predictive value of Apgar scores for developmental outcome in premature infants.

For more than two decades, Apgar scores have been used to predict developmental outcome in newborns. However, most studies have used full-term babies for their data base, and the predictive value of Apgar scores for low birthweight infants has remained unclear. This study was designed to provide a data base for premature infants, demonstrating to what degree Apgar scores predict developmental outcome. We tested Apgar scores alone and in combination with two other easily quantified variables, birthweight and gestational age, as predictors of risk for 256 infants weighing less than 1800 gm at birth. Although significant correlations existed between Apgar scores and Bayley Mental and Psychomotor Developmental Indices, multiple regression analyses demonstrated that these relationships were not significant independent of birthweight and gestational age. That is, after controlling for birthweight and gestational age, Apgar scores did not predict morbidity in low birthweight infants and should not be used to provide a developmental prognosis.

Apgar Score↗
PubMed1988

Maternal weight gain: effect on infant birth weight among overweight and average-weight low-income women.

A study was performed to compare the influence of pregnancy weight gain on infant birth weight and outcome among two groups of indigent women from the rural South: those who were highly overweight before pregnancy (greater than or equal to 135%) and those who were of average weight (90% to 120% of standard weight for height). The groups had comparable numbers of black and white subjects. Pregnancy weight gain affected birth weight in the average-weight group but did not significantly affect birth weight in the highly overweight group. Infant outcomes for both groups were similar. These findings suggest that consideration should be given to not requiring a minimum weight gain for women whose degree of overweight equals or exceeds 135% of standard body weight for height.

Birth Weight↗
PubMed1988

Evaluation of ultrasound diagnosis of fetal anomalies in women with pregestational diabetes: University of Florida experience.

Fetal congenital anomalies have become the major cause of perinatal morbidity and mortality in pregnancies complicated by insulin-dependent diabetes. We evaluated the use of level II ultrasound in predicting congenital anomalies, to determine if the management of pregnant women with insulin-dependent diabetes would be altered by these findings. We examined 43 insulin-dependent diabetic pregnancies. In this group, 10 newborns (23%) were diagnosed either at birth or later to have an abnormality. Of these, four (9%) were diagnosed by ultrasound. Of the seven cases that were undiagnosed, three women did not undergo the level II examination, two women had lesions undetectable by ultrasound, and in two women cardiac abnormalities were missed. Of the four congenital anomalies that were prenatally diagnosed, the findings influenced the management in three cases. The level II ultrasound used as a screening test had a 67% sensitivity and a 100% specificity, with a positive predictive value of 100% and a negative predictive value of 91%. We conclude that high-resolution ultrasound may be used as a screening tool for congenital anomalies in the insulin-dependent diabetic pregnancy. This study also suggests that the use of fetal echocardiography with evaluation of aortic and pulmonary outflow tracts, the arch of the aorta, and ventricular size may be helpful in the diagnosis of fetal cardiac anomalies in the pregnant woman with insulin-dependent diabetes.

Adolescent↗
PubMed1988

Continuous-wave Doppler ultrasound and decreased amniotic fluid volume in pregnant women with intact or ruptured membranes.

The cause(s) of decreased amniotic fluid in the absence of fetal anomalies and intrauterine growth retardation is not clear. A prospective study was performed to evaluate umbilical and uterine artery Doppler velocimetric results in pregnancies complicated by decreased amniotic fluid. Three medically high-risk groups were studied: women with (1) normal fluid and intact membranes, (2) decreased fluid and intact membranes, and (3) decreased fluid and ruptured membranes. The decreased fluid/intact membranes group had a significantly increased incidence of abnormal uterine artery waveforms (diastolic notching or absence of end-diastolic velocity); however, uterine systolic/diastolic ratios were not significantly different. The umbilical systolic/diastolic ratios were marginally higher in the intact membranes/decreased fluid group when compared with the ruptured membranes group. This study suggests that problems with maternal blood supply to the placenta may be related to decreased amniotic fluid when membranes are intact.

Adult↗
PubMed1988

Rh sensitization after third-trimester fetal death.

Three primigravidas developed Rh sensitization after unexplained third-trimester fetal death. One patient manifested sensitization after the diagnosis of fetal death had been made but before delivery occurred. The other two demonstrated anti-D antibodies early in the next pregnancy, despite having received postpartum Rh immunoglobulin. Unsensitized Rh-negative women with unexplained third-trimester fetal death should be screened routinely for fetomaternal hemorrhage when fetal death is discovered, so that adequate prophylaxis against Rh sensitization can be given.

Adult↗
PubMed1988

Prospective pricing model for neonatologists and obstetricians in tertiary care centers.

According to the new federal diagnosis-related group (DRG) system, hospitals are reimbursed fixed sums based on discharge diagnoses, rather than variable sums that depend on specific goods and services consumed and number of days hospitalized. The government is now exploring DRGs as a potential mechanism for reimbursing physicians. In Florida, two DRG-type reimbursement systems were developed for neonatal and obstetrical hospitalizations in tertiary care settings, as departures from the federal DRG system. Called neonatal care groups (NCGs) and obstetrical care groups (OBCGs), both classification systems predicted hospital charges in these settings more accurately than did federal DRGs. The feasibility of a prospective pricing system for neonatologists and obstetricians based on NCGs and OBCGs was investigated. The data showed that neonatologists' charges had a high correlation with hospital charges (r = .90) and that increasing levels of intensity of care as defined by the NCGs were reflected by consistent increases in reimbursement to neonatologists. If the NCG system were to be applied, neonatologists would receive compensation equivalent to that which they currently earn according to the fee-for-service system. In contrast, obstetricians' charges bore almost no relationship to hospital charges. However, modest differences in obstetrician's charges did emerge as a reflection of number of complications, which are incorporated into the OBCG categories; this suggests that a reimbursement system based on hospital OBCG categories might be applied to obstetricians.

Diagnosis-Related Groups↗
PubMed1987

Prospective pricing system by diagnosis-related groups: comparison of federal diagnosis-related groups with high-risk obstetric care groups.

Of 468 diagnosis-related groups identified by the federal government for Medicaid reimbursement, 15 are related to obstetric hospital care. Each diagnosis-related group is considered a distinct group in which cases are homogeneous with respect to resource consumption. Because the diagnosis-related group system is based primarily on data from community and secondary care hospitals, it does not differentiate sufficiently among high-risk obstetric patients seen at tertiary care institutions, such as Florida's Regional Perinatal Intensive Care Centers. We developed an alternative scheme for diagnosis-related groups, called obstetric care groups, using the federal diagnosis-related groups as the model from which to depart. Data collected for 4192 women during a 2 1/2-year period indicate that obstetric care groups provide more homogeneous groups than diagnosis-related groups for our population of high-risk patients. The obstetric care groups differentiate between no complications, one complication, and two or more complications, while the diagnosis-related groups differentiate only between no complications and one or more complications. Also, complications for obstetric care groups are based on only 19 diagnoses that contribute significantly to resource consumption, while the list of possible complications exceeds 200 for diagnosis-related groups. Although the obstetric care group classification system is simpler than that for diagnosis-related groups, it results in a more accurate reimbursement of hospitalization charges for high-risk obstetric care.

Diagnosis-Related Groups↗
PubMed1987

Hepatitis B: a case for prenatal screening of all patients.

Evaluation of a mass screening program to detect hepatitis B surface antigen in the obstetric population of Shands Hospital, University of Florida in Gainesville, from January 1, 1983, through December 31, 1985, was undertaken. Prevalence of hepatitis B surface antigen seropositivity was 0.54%. Review of medical records revealed that 67% of patients with positive hepatitis B surface antigen screens had no risk factors identifiable by routine prenatal history. Although all patients were screened on admission to the hospital, the results of the immunoassay were not available in time for staff to institute isolation procedures for the laboring mother or unwashed neonate. In 82% of the cases, treatment of neonates occurred later than 12 hours after delivery (the current Centers for Disease Control recommendation). It is recommended that prenatal screening of all patients with a hepatitis B surface antigen immunoassay be done by 34 weeks' gestation where the patient population is of predominantly low socioeconomic status to ensure appropriate isolation and timely neonatal immunoprophylaxis.

Enzyme-Linked Immunosorbent Assay↗
PubMed1987

The relationship of Apgar scores, gestational age, and birthweight to survival of low-birthweight infants.

While Apgar scores provide a valid prediction of mortality in term infants (primarily reflecting asphyxia), intervening variables in premature newborns complicate interpretation. Physiologic states normal to preterm infants (such as, decreased muscle tone) can depress scores but may not influence survival significantly. Therefore the relationship between Apgar scores and survival in term and preterm infants differs. Because of the paucity of studies on preterm infants, we tested Apgar scores, as well as birthweight and gestational age, as outcome predictors in 748 low-birthweight infants (500-1800 gm). Our purpose was to assess the relationship between 1- and 5-minute Apgar scores and survival, and to evaluate all combinations of the four variables as outcome predictors. Univariate analysis showed a significant relationship between each of the four variables and survival; however, no single variable accounted for more than 32% of the variance in outcome, thus no single factor could be invoked as the major determinant of survival. Logistic regression analyses demonstrated the interrelationships of the four variables to survival. While both Apgar scores were related to survival, independent of the effects of birthweight and gestational age, they were slightly less predictive than either of these variables alone. However, when 1- and 5-minute Apgar scores were combined with gestational age, the predictive value was slightly better than any of the four variables alone or in other possible combinations.

Apgar Score↗
PubMed1987

A unique 7p/12q chromosomal abnormality associated with recurrent abortion and hypofibrinogenemia.

Recurrent first trimester abortions led to evaluation of a 25-year-old woman. Studies revealed she had hypofibrinogenemia (68 mg/dL) without evidence of dysfibrinogenemia or increased fibrinogen turnover. She was also found to have a unique 46,XX, t(7;12) (p 15.2;q24.31) karyotype. Hypofibrinogenemia and identical chromosomal abnormalities were found in other members of her kindred. Southern blots of genomic DNA from the patient, her mother, and her daughter hybridized to human fibrinogen probes showed alpha, beta, and gamma fibrinogen genes to be present and without structural alterations when compared to normal controls. We conclude that the chromosomal abnormality and the hypofibrinogenemia are related but in an unclear manner. Because fibrinogen infusion in the proposita was associated with successful gestation, we also concluded that the chromosomal abnormality itself was not responsible for the repeated abortions but that fibrinogen concentration may be critical in securing implantation.

Abortion, Habitual↗
PubMed1986

Sonographic detection of fetal urinary-tract anomalies.

The diagnosis of urinary-tract anomalies in the fetus can frequently be made with antenatal ultrasound imaging. This report details 19 cases of fetal urinary-tract malformation diagnosed during a 30-month period. Early onset and more complete urinary-tract obstruction, oligohydramnios, renal dysplasia, and pulmonary hypoplasia occur frequently in cases where urinary-tract anomalies were detected in utero. The frequent association of other major structural anomalies, severe renal damage, and irreversible pulmonary hypoplasia make imperative an intensive evaluation of the fetus before considering invasive surgical procedures.

Female↗
PubMed1985

Immunocytochemical localization of relaxin in human decidua and placenta.

Specimens from 20 human term placentas were stained with 4 different antisera produced against porcine relaxin (Rlx) using the avidin-biotin immunoperoxidase procedure. Cells of the parietal decidua adherent to the fetal membranes, cells of the chorionic cytotrophoblast, as well as cells of the placental basal plate consistently stained with all 4 anti-Rlx sera. Occasionally, Rlx was detected in epithelial cells lining the amniotic membrane. The syncytiotrophoblast stained for Rlx in 2 specimens only. This response was seen only in syncytiotrophoblast that lined villi in close proximity to the basal plate. Syncytiotrophoblast of the chorionic villi either did not stain at all or gave very weak positive immunostaining with the anti-Rlx sera in all specimens. No difference was noted in staining patterns among placentas delivered by elective cesarean section or vaginal delivery.

Chorionic Villi↗
PubMed1984

Fetal pulmonary maturity in isoimmunized pregnancies.

That the lecithin/sphingomyelin (L/S) ratio correlates very closely with fetal gestational age in the uncomplicated pregnancy is well accepted. The presence of fetal or maternal disease has been found to accelerate or retard the development of fetal lung maturity in certain pregnancies. Although only a very small number of isoimmunized pregnancies has been evaluated in the obstetric literature, there is general acceptance that most isoimmunized pregnancies have delayed pulmonary maturation. Our observation has been that, in mild to moderately severe isoimmunized pregnancies, fetal lung maturation is not delayed. This study was designed to compare fetal pulmonary maturation in pregnancies affected by isoimmunization to that in a control group of unaffected but sensitized pregnancies. The results of this study suggest that pulmonary maturation in the mild to moderately affected pregnancy as measured by the L/S ratio is neither delayed nor accelerated but unchanged when comparison is made to the control group.

Amniotic Fluid↗
PubMed1984

Intrauterine positional deformations masquerading as multiple congenital malformations.

A 1,340-g male neonate was delivered by emergency cesarean section at 28 weeks' gestation following failed therapy with isoxsuprine hydrochloride and fetal distress. Transverse-lie presentation with the posterior side of the thorax wedged into the maternal pelvis and the head flexed firmly against the anterior side of the thorax led to a severe deformation sequence initially interpreted as multiple congenital malformations. This case illustrates the difficulty in distinguishing between pure deformations and malformations with and without subsequent deformations. It also emphasizes the clinician's need for a definitive diagnosis to guide the management of suspected malformations that are potentially lethal or portend a poor neurodevelopmental outcome.

Abnormalities, Multiple↗
PubMed1984

Clinical utility of the relationship between fetal femur length and biparietal diameter.

The relationship between fetal femur length and biparietal diameter on ultrasound examination was evaluated in a large, unselected obstetric population of 12-40 weeks' gestational age. The derived ratio of fetal femur length to biparietal diameter was evaluated retrospectively as a tool for examining the technical reliability of fetal measurements obtained and as a screening mechanism for detecting asymmetric fetal development. The ratio of femur length to biparietal diameter is of value as an aid to the detection of fetal developmental anomalies and should be a routine parameter considered in the performance of an obstetric ultrasound examination.

Birth Weight↗