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K J Blakemore

Publications and source records attributed to K J Blakemore.

At least 19 recordsLinked to original sources
PubMed2002

Evidence of intrapartum hypoxia-ischemia is not present in the majority of cases of neonatal seizures.

OBJECTIVE: To determine the extent to which neonatal seizures are associated with intrapartum hypoxia-ischemia. METHODS: In this case-control study, all neonates diagnosed with seizures at a single institution from 1988 to 1999 were compared to a control group without seizures matched in a 2:1 fashion for gestational age at delivery, birth weight and mode of delivery. Data were abstracted from the maternal and neonatal charts. Parametric variables were compared using an independent samples t test, and non-parametric variables were compared using a Fisher exact test, with p < 0.05 being considered significant. RESULTS: There were 13 cases of neonatal seizures identified, of which one was chromosomally abnormal and excluded from further analysis. For the cases, the mean gestational age at delivery was 34.8 +/- 6.9 weeks, with four preterm and eight term deliveries. The mean birth weight for the cases was 2684 +/- 1369 g (range 590-4350 g). For both cases and controls, 83% were delivered vaginally and 17% by Cesarean section. For term neonates with seizures, the mean length of stay was 11.6 +/- 5.0 days, as compared to 2.5 +/- 0.9 days in the control group (p < 0.001). A 1-min Apgar score of < 7 was found in six of 12 (50%) cases and seven of 24 (29%) controls, and a 5-min Apgar score of < 7 was found in four of 12 (33%) cases and four of 24 (17%) controls (non-significant). In the controls, the mean base excess was -2.8 +/- 2.6 mEq/l, and the mean umbilical arterial pH was 7.28 +/- 0.09. In the case group, two infants born at 24 weeks did not have an umbilical arterial blood gas obtained; in the remaining cases, the mean base excess was -7.6 +/- 6.9 mEq/l (p = 0.02), and the mean cord pH was 7.17 +/- 0.23 (p = 0.065), with only three of ten (30%) having a pH < 7.00 (p = 0.02). CONCLUSION: Clinically significant acidosis was found in only 30% of neonates who developed seizures, and only one of 12 cases (8%) could possibly have met the criteria of the American College of Obstetricians and Gynecologists for neurological morbidity linked to intrapartum asphyxia. The majority of cases of neonatal seizures were not associated with evidence of intrapartum hypoxia-ischemia.

Acidosis↗
PubMed2001

Non-mosaic trisomy 20 presenting at 21 weeks' gestation as a thoraco-abdominal mass.

Non-mosaic trisomy 20 is rare in fetuses surviving beyond the first trimester. We report a case of a fetus with non-mosaic trisomy 20 in amniotic fluid cultures obtained during the prenatal evaluation of an unusual thoraco-abdominal mass which was found at autopsy to be pulmonary sequestration. Gross inspection and autopsy of the fetus revealed multiple anomalies.

Abdominal Neoplasms↗
PubMed2000

Cloacal outlet obstruction with an ectopic ureter.

Cloacal malformation occurs in approximately 1 in 50,000 live female births. Prenatal ultrasound may lead to the diagnosis in selected cases. We report an unusual case of prenatally detected single-system hydronephrosis with a nonvisible bladder and worsening oligohydramnios. Labor was induced at 35 weeks' estimated gestational age. On physical examination, a single perineal opening was noted consistent with cloaca. Endoscopy revealed an obstructed ectopic ureter at the level of the sphincter, an undeveloped bladder and vagina, and a fistula to the rectum. A low loop cutaneous ureterostomy and right upper quadrant loop colostomy were performed. The absence of a typical fluid-filled pelvic structure may confound the prenatal diagnosis of cloaca.

Abnormalities, Multiple↗
PubMed2000

Prediction of birth weight by ultrasound in the third trimester.

OBJECTIVE: To compare the accuracy of predicted birth weight by the gestation-adjusted projection method using ultrasonographic measurements obtained just before and at term. METHODS: The study group comprised patients with singleton pregnancies who underwent sonograms between 34.0 and 36.9 weeks' gestation (period 1) and at 37 weeks and beyond (period 2). The mean error in birth weight prediction, absolute birth weight error, and signed and absolute percent errors were compared with paired t tests. Thus, each patient served as her own control. RESULTS: The study included 138 patients undergoing 276 sonograms. The mean absolute error of the predicted birth weight was smaller for period 1 than for period 2 (197 +/- 167 g compared with 235 +/- 209 g, P =.019). The mean absolute percent error was 6.2 +/- 5.2% for period 1 compared with 7.4 +/- 6.3% for period 2 (P =.019). These same trends were observed when fetuses with suspected growth abnormalities were examined separately. Averaging data from both gestational periods did not improve the prediction of birth weight. CONCLUSION: Sonograms between 34.0 and 36. 9 weeks' gestation allow for more accurate prediction of birth weight than sonograms later in gestation. Though these differences are small and not clinically significant, this study indicates that serial sonograms in the late third trimester do not improve the ability to predict birth weight, even in abnormally grown fetuses. A single sonogram between 34 and 37 weeks' gestation is recommended for prediction of birth weight.

Adolescent↗
PubMed1999

Molecular cytogenetic analysis and clinical findings in a newborn with prenatally diagnosed rec(7)dup(7q)inv(7)(p22q31.3)pat.

We report prenatal and early postnatal findings in a newborn with a partial trisomy of chromosome 7 (7q31.3-qter), arising from meiotic recombination of a paternal pericentric inversion, inv(7)(p22q31.3). The inversion breakpoints were localized and the regions of duplication and deletion were defined by fluorescence in situ hybridization (FISH) analysis using a series of locus-specific and subtelomeric probes. To our knowledge, only three cases involving a recombinant 7 with duplication of 7q have been reported, two of these being first cousins. The clinical findings in our patient included skeletal abnormalities, facial dysmorphism, dilated cerebral ventricles, microretrognathia and short neck. These findings and some aspects of the neonatal course were consistent with the phenotype previously reported for duplication of distal 7q, without associated monosomy for sequences from another chromosome.

Abnormalities, Multiple↗
PubMed1999

Station at onset of active labor in nulliparous patients and risk of cesarean delivery.

OBJECTIVE: To determine whether term nulliparas with an unengaged vertex presentation at onset of active labor have a higher risk for cesarean delivery. METHODS: A retrospective cohort of 1250 randomly chosen nulliparous patients at 37-42 weeks' gestation who delivered between 1988 and 1989 were selected. Four hundred forty-seven patients were excluded because of nonvertex presentation, cesarean delivery before active phase of labor, multiple gestation, delivery at less than 37 weeks' or greater than 42 weeks' gestation, induction of labor, or missing charts. For the purpose of this study, active labor was defined as regular contractions with cervical dilatation of at least 3 cm. The station at onset of active labor was recorded. Engagement was considered to be at station 0 or below. RESULTS: Of the 803 patients in the study group, 567 presented unengaged and 236 patients presented engaged. The cesarean rates differed significantly between the two groups: 14% of those unengaged compared with 5% of those engaged (chi2 = 11.9, P < .001). After adjusting for confounding variables, engagement at the time of onset of active labor was associated with lower risk of cesarean delivery (odds ratio .512, 95% confidence interval .285, .922). CONCLUSION: Eighty-six percent of nulliparas with an unengaged vertex at onset of active labor delivered vaginally. Engaged vertex at the onset of active labor was associated with a lower risk of cesarean delivery.

Cesarean Section↗
PubMed1999

Helical CT amniography of congenital diaphragmatic hernia.

OBJECTIVE: Accurate prenatal diagnosis of congenital diaphragmatic hernia is important for perinatal planning and potential fetal surgery. We describe the application and usefulness of helical CT amniography in the evaluation of suspected congenital diaphragmatic hernia in three fetuses. CONCLUSION: Helical CT amniography is an efficient means for evaluation of congenital diaphragmatic hernia. Accurate diagnosis was made in all three patients.

Amnion↗
PubMed1999

Second-trimester maternal serum analyte levels associated with fetal trisomy 13.

The aim of this study was to determine whether pregnancies affected by fetal trisomy 13 are associated with second-trimester maternal serum analyte levels different from those typical of the unaffected population. Pregnancies with trisomy 13 were identified through cytogenetics laboratories. Those which had second-trimester maternal serum screening analyte measurements were further evaluated. Maternal serum analyte levels for each case and five matched controls were statistically analysed by matched ranked-sum analysis. 28 cases of fetal trisomy 13 were identified. The median AFP, uE3 and hCG levels were 1.35 MoM, 0.71 MoM and 0.90 MoM, respectively. Only uE3 levels were statistically different (p < 0.01) from those for the unaffected population. These data suggest that second-trimester maternal serum AFP, uE3 and hCG levels are not useful in detecting fetal trisomy 13 and protocols already existing for Down syndrome or trisomy 18 screening will not detect the majority of cases of this aneuploidy.

Adolescent↗
PubMed1998

Region-specific FISH probes used to identify and characterize an interstitial paracentric inv(21)(q22.1q22.3).

Region-specific probes developed for the diagnosis of specific syndrome, can be adapted to elucidate the exact nature of certain chromosomal structural anomalies. We describe the use of FISH probes in characterizing a prenatally diagnosed chromosome rearrangement. An abnormal chromosome 21 was detected during amniocentesis for maternal age indication, and a similar appearing chromosome 21 was found in the mother. The exact nature of the rearrangement was not immediately evident from G-banded karyotypes. FISH was performed using a whole chromosome painting probe, as well as the region-specific probes D21S65 (21q21-22.1), D21S55 (21q22.3) and D21S1219/D21S1220 (21q22.3-qter) (Oncor). Results showed an interstitial paracentric inversion, with breakpoints in bands 21q22.1 and 21q22.3, which was identical in the mother and the fetus: 46,XX,?inv(21)(q).ish inv(21)(q22.1q22.3)(wcp+.D21S65 mv, D21S55 mv, D21S1219/D21S1220 st). In this case, FISH using region-specific probes was helpful in characterizing the inversion and aided in the genetic counselling of risk assessment for the family.

Adult↗
PubMed1997

A paternally derived inverted duplication of 7q with evidence of a telomeric deletion.

We report on a de novo constitutional rearrangement involving the long arm of chromosome 7 in a second trimester fetus with the karyotype of 46,XX, inv dup del (7)(pter-q36::q36-q21.2:) pat. Both a large duplication (q21.2-q36) and a small deletion (within q36) were confirmed by FISH studies. DNA analysis on the family showed that the abnormal chromosome was derived from a single paternal homolog. A mechanism is proposed in light of this finding. The phenotype at autopsy was consistent with reported cases of similar duplications in chromosome 7 in that hydrocephalus, a depressed nasal bridge, low set ears, microretrognathia and a short neck were present.

Abortion, Therapeutic↗
PubMed1997

Managed care does not lower costs but may result in poorer outcomes for patients with gestational diabetes.

OBJECTIVE: Our purpose was to compare the costs of prenatal care and subsequent maternal and neonatal outcomes in patients with gestational diabetes cared for in an inner-city university hospital house staff clinic versus an inner-city managed care organization. STUDY DESIGN: A retrospective cohort study was conducted. The groups consisted of 115 patients with gestational diabetes who were cared for in a house staff clinic and a demographically similar group of 85 patients cared for in a neighborhood managed care organization. The groups were examined regarding baseline demographics, intensity of prenatal care, maternal and neonatal outcomes, and total cost of the provision of care. RESULTS: There was no difference between groups in the total cost of maternal-infant care. A larger percentage of patients in the house staff group saw the physician frequently. In contrast, patients cared for in the managed care organization underwent more tests of fetal well-being. There was a greater rate of neonatal macrosomia in the managed care organization group compared with the house staff group. CONCLUSIONS: Managed care does not decrease the cost of caring for patients with gestational diabetes but does lead to a greater rate of neonatal macrosomia, which may reflect poorer glucose control.

Adult↗
PubMed1996

A prospective randomized trial of two solutions for intrapartum amnioinfusion: effects on fetal electrolytes, osmolality, and acid-base status.

OBJECTIVE: Our purpose was to compare the effects of intrapartum amnioinfusion with normal saline solution versus lactated Ringer's solution plus physiologic glucose on neonatal electrolytes and acid-base balance. STUDY DESIGN: Patients undergoing amnioinfusion for obstetric indications were randomized to receive normal saline solution or lactated Ringer's solution plus physiologic glucose at standardized amnioinfusion rates. Data were collected prospectively on maternal demographics, course of labor, and maternal and neonatal outcome. Arterial cord blood was obtained for analysis of electrolytes, glucose, osmolality, lactic acid, and blood gases. Control subjects with normal fetal heart rate patterns, and clear amniotic fluid not receiving amnioinfusion were studied concurrently. RESULTS: Data were collected on 59 patients (21 normal saline solution, 18 lactated Ringer's solution plus physiologic glucose, and 20 controls). Maternal demographics, course of labor, and neonatal outcome were similar in all three groups. Cesarean sections were performed more often in the amnioinfusion groups (33.3% for normal saline solution, 38.9% for lactated Ringer's solution plus physiologic glucose) than in the control group (5.0%), p < 0.05. Cord arterial electrolytes, glucose, osmolality, lactic acid, and blood gases were not altered by amnioinfusion with either solution. CONCLUSION: Intrapartum amnioinfusion with normal saline solution or lactated Ringer's solution plus physiologic glucose has no effect on neonatal electrolytes or acid-base balance.

Acid-Base Equilibrium↗
PubMed1996

Lysosomal enzymuria in preeclampsia.

We hypothesize that the preeclamptic patient has proximal tubule epithelial injury, which leads to the release of lysosomal enzymes, and that the excretion of these enzymes might serve as a diagnostic or predictive marker in preeclamptic women. The study group consisted of 14 women with preeclampsia (10 severe and 4 mild, as defined by The American College of Obstetricians and Gynecologists criteria) and 28 normotensive controls with singleton pregnancies at 27 to 41 weeks. There were no significant differences between the two groups for gestational age, maternal age, or race. Maternal serum and urine specimens were prospectively obtained and analyzed for beta-glucuronidase, beta-hexosaminidase, alpha-galactosidase, beta-galactosidase, and alpha-mannosidase using fluorometric assays. Median serum and urine activities and fractional excretions of each of the five hydrolases were compared between the two study groups using the Mann-Whitney two-sample rank test. The serum enzyme activities of beta-hexosaminidase (P = 0.002), alpha-galactosidase (P = 0.0001), and alpha-mannosidase (P = 0.02) were significantly lower in preeclamptic patients than in controls. The urine enzyme activities of beta-glucuronidase (P = 0.001), alpha-galactosidase (P = 0.002), beta-galactosidase (P 0.0003), and alpha-mannosidase (P = 0.003) were significantly higher in the preeclamptic patients. The fractional enzyme excretions of all five lysosomal hydrolases were higher in preeclamptic patients than in controls with P < or = 0.0003 for each enzyme. Preeclampsia is associated with a significant decrease in serum activities of three of the five hydrolases studied, a significant increase in urine enzyme activities in four of the five hydrolases studied, and a significant increase in the fractional excretion of all five lysosomal hydrolases.

Adolescent↗
PubMed1995

An accessory marker derived from chromosome 20 and its co-existence with a mosaic trisomy 20 cell line.

We report a 16-month-old boy with delayed psychomotor development, dysmorphic features, and failure to thrive. He had a mosaic karyotype detected prenatally: mos 46,XY/47,XY, +r(20)/47,XY, +20. After birth, the abnormal cell lines were confirmed in a number of tissues. The small ring chromosome was identified using fluorescence in situ hybridization as derived from chromosome 20. We compared our patient with previously reported cases of mosaic trisomy 20 detected prenatally and associated with an abnormal phenotype. In an attempt to characterize an r(20) syndrome, we also compared our case with two similar reports in the literature.

Cell Line↗
PubMed1995

Molecular genotyping of fetal platelet antigens with uncultured amniocytes.

OBJECTIVE: Amino acid substitutions in platelet membrane glycoproteins result in alloantigens implicated in neonatal alloimmune thrombocytopenia. We report the use of the reverse dot blot technique to genotype the five major fetal platelet alloantigens from amniotic fluid cells. STUDY DESIGN: We evaluated a patient with Bakb platelet antibodies who had a previous pregnancy complicated by fetal intracranial hemorrhage. The father was heterozygous Baka/Bakb, giving the pregnancy a 50% risk for platelet incompatibility between mother and fetus. Amniotic fluid was obtained at 16 weeks. Deoxyribonuleic acid was extracted from uncultured amniocytes and amplified with polymerase chain reaction. These products were hybridized to filters containing oligonucleotides specific for each of the 10 different platelet antigen alleles. Reactivity was detected with a chromogenic substrate. RESULTS: The reverse dot blot genotyping of uncultured amniocytes revealed the fetus to be Baka/Baka, thus not at risk for neonatal alloimmune thrombocytopenia. CONCLUSION: Precise knowledge of fetal platelet type by amniocentesis could obviate the need for fetal blood sampling and significantly alter prenatal management of neonatal alloimmune thrombocytopenia.

Adult↗
PubMed1995

Insulin-like growth factor I receptor expression and function in fibroblasts from two patients with deletion of the distal long arm of chromosome 15.

Most patients with deletion of the distal long arm of chromosome 15 have intrauterine growth retardation and postnatal growth deficiency in addition to developmental abnormalities. It has been proposed that the absence of one copy of the insulin-like growth factor I (IGF-I) receptor gene may play a role in the growth deficiency seen in this syndrome. To address this question we examined IGF-I receptor expression and function in fibroblasts from two patients with deletion of the distal long arm of chromosome 15 (15q26.1-->qter). Quantitative Southern blot analysis of the IGF-I receptor gene was performed on HindIII digests of fibroblast DNA. Radioactivity in the 1.7-kilobase receptor fragment in the two patients was 55% and 51% of the values in controls, consistent with the absence of one copy of the IGF-I receptor gene. IGF-I receptor messenger ribonucleic acid levels were quantitated by a solution hybridization/nuclease protection assay. Receptor messenger ribonucleic acid levels in the two patients were 45% and 52% of the values in controls. Northern blotting demonstrated normal size IGF-I receptor transcripts and affinity crosslinking of [125I]IGF-I to Triton X-100-solubilized fibroblasts demonstrated a normal size receptor in the patients. Analysis of placental membranes prepared from one patient revealed no difference in [125I]IGF-I binding. In the patients' fibroblasts, however, binding of [125I]long [R3]-IGF-I to the IGF-I receptor was significantly reduced, as assessed by the amount of radioactivity competed by the monoclonal antibody alpha IR-3 or insulin and Scatchard analysis of binding data. To assess IGF-I receptor function, stimulation of [alpha-1-14C]-methylaminoisobutyric acid transport and stimulation of [methyl-3H]thymidine incorporation into DNA by a full range of IGF-I concentrations was examined in patient and control fibroblasts. There was a significant decrease in the maximal response to IGF-I in both assays for one of the two patients when data were expressed as fold response over the basal value. However, there was no evidence for impairment of response to IGF-I in either patient's fibroblasts when data were expressed as net stimulation (maximal response minus basal). In conclusion, although IGF-I receptor expression was decreased in fibroblasts from two patients with deletion of the distal long arm of chromosome 15, we were unable to provide conclusive evidence for impairment of the biological response to IGF-I.

Child↗