Kidney preservation at subzero temperatures using a novel storage solution and insect ice-binding proteins.

BACKGROUND: Contemporary kidney preservation methods involve storing at 4 degree C up to 24 h prior to transplantation. By decreasing the storage temperature to below 0 degree C, we hypothesized that the safe storage time could be significantly lengthened. OBJECTIVE: The efficacy of a proprietary CryoStasis (CrS) storage solution for the subzero preservation of kidneys was tested, with or without addition of a hyperactive insect antifreeze protein (TmAFP). MATERIALS AND METHODS: Rat kidneys were stored in either University of Wisconsin (UW) solution (4 degree C, 24 h), CrS (-2 degree C, 48 h), or CrS with 61.5 µM TmAFP (-4.4 degree C, 72 h). Following storage, viability was assessed with MTT reduction assays and live vs. dead cell (FDA/PI) staining. Markers of ischemic damage were analyzed using fluormetric substrates for caspase-3 and calpain activity. RESULTS: Kidneys stored in CrS for 48 h and CrS with TmAFP for 72 h displayed similar levels of enzymatic activity compared to 24 h UW controls. CONCLUSION: This methodology shows promise to prolong the safe storage time of kidneys and offers the potential of increased organ availability for renal transplants.

Fetal heart rate deceleration detection using a discrete cosine transform implementation of singular spectrum analysis.

OBJECTIVES: To develop a singular-spectrum analysis (SSA) based change-point detection algorithm applicable to fetal heart rate (FHR) monitoring to improve the detection of deceleration events. METHODS: We present a method for decomposing a signal into near-orthogonal components via the discrete cosine transform (DCT) and apply this in a novel online manner to change-point detection based on SSA. The SSA technique forms models of the underlying signal that can be compared over time; models that are sufficiently different indicate signal change points. To adapt the algorithm to deceleration detection where many successive similar change events can occur, we modify the standard SSA algorithm to hold the reference model constant under such conditions, an approach that we term "base-hold SSA". The algorithm is applied to a database of 15 FHR tracings that have been preprocessed to locate candidate decelerations and is compared to the markings of an expert obstetrician. RESULTS: Of the 528 true and 1285 false decelerations presented to the algorithm, the base-hold approach improved on standard SSA, reducing the number of missed decelerations from 64 to 49 (21.9%) while maintaining the same reduction in false-positives (278). CONCLUSIONS: The standard SSA assumption that changes are infrequent does not apply to FHR analysis where decelerations can occur successively and in close proximity; our base-hold SSA modification improves detection of these types of event series.

The expression of congenital ichthyosiform erythroderma in second trimester fetuses of the same family: morphologic and biochemical studies.

The first born offspring of first-cousin parents was affected with a keratinization disorder thought to be nonbullous congenital ichthyosiform erythroderma (CIE). In each of three subsequent pregnancies, the parents elected to have prenatal diagnosis based on evaluation of fetal skin biopsies. The epidermis of fetus 1 was identical to normal 21-wk estimated gestation age (EGA) fetal epidermis, but because keratinization begins normally around 24 wk EGA, the procedure was repeated 4 wk later. A thin epidermis with a few layers of stratum corneum indicated a normal fetus and a healthy infant was born at term. Skin biopsy samples from fetus 2 gave conflicting results; the epidermis of one sample appeared normal but the second had 5-15 layers of incompletely keratinized cells superficial to basal and intermediate layers. The hair canals of both samples were hyperkeratotic. Pelleted amniotic fluid cells contained aggregates of incompletely keratinized epidermal cells and concentric rings of keratinized cells. The fetus was thought to be affected and the pregnancy terminated. Regional variation in epidermal thickness and keratinization was noted upon gross examination of the fetus and by histology of the skin. Marked hyperkeratinization of follicles was evident in all regions. No abnormal keratins were expressed in the affected epidermis but epidermal lipids analyzed from two body regions had a lower triglyceride content and a higher content of free sterols compared with age-matched, normal fetal epidermis. Immunolabeling for markers of differentiation revealed variable stages of epidermal differentiation according to region. Four structurally identical biopsy samples were obtained from a third fetus. The epidermis appeared normal for age and hair canals were keratinized to various extents. The pregnancy was continued and at 33 wk a male infant was born with a severe ichthyosis of the face and scalp and fine, white scaling on the body. The epidermis of both the severely and mildly affected regions of the newborn had a thick, compact stratum corneum and other features of CIE. Scars from all four fetal biopsies were identified on the trunk, in areas which appeared less affected clinically. This study reports, for the first time, the criteria for prenatal diagnosis of CIE and the variable expression of this disorder in the midtrimester fetus. More importantly, it demonstrates the risks and pitfalls of this in utero diagnosis based on epidermal morphology.

Maternal anthropometry and idiopathic preterm labor.

OBJECTIVE: To assess the etiologic role of maternal short stature, low pre-pregnancy body mass index (BMI), and low rate of gestational weight gain in idiopathic preterm labor. METHODS: We carried out a three-center case-control study of 555 women with idiopathic onset of preterm labor (before 37 completed weeks), including two overlapping (ie, nonmutually exclusive) subsamples: cases with early preterm labor (before 34 completed weeks) and cases with recurrent preterm labor (before 37 completed weeks plus a history of prior preterm delivery or second-trimester miscarriage). Controls were matched to cases by race and smoking history. All subjects responded in person to questions about height, pre-pregnancy weight, gestational weight gain, and obstetric and sociodemographic histories. RESULTS: Maternal height, pre-pregnancy weight, and gestational weight gain demonstrated excellent test-retest reliability, with intra-class correlation coefficients of 0.97, 0.99, and 0.91, respectively. Based on matched analyses, women with a height of 157.5 cm or less had an increased risk of idiopathic preterm labor (odds ratio [OR] 1.85, 95% confidence interval [CI] 1.25-2.74), as did those with a pre-pregnancy BMI less than 19.8 kg/m2 (OR 1.63, 95% CI 1.09-2.44) or a gestational weight gain rate less than 0.27 kg/week (OR 1.74, 95% CI 1.16-2.62). Conditional logistic regression models containing all three anthropometric variables and controlling for parity, marital status, language, age, and education yielded virtually identical point estimates and CIs. CONCLUSION: Maternal short stature, low pre-pregnancy BMI, and low rate of gestational weight gain may lead to shortened gestation by increasing the risk of idiopathic preterm labor.

Obstetric outcome in women after multiple spontaneous abortions.

Obstetric outcome in 88 women with a past history of three or more consecutive pregnancy losses was studied. The results were compared to those in our total obstetric population for the same period (control group). The incidence of small-for-gestational-age infants, prematurity, low-birth-weight infants and toxemia in the study group was not significantly different from that in the control group. Gestational diabetes and chronic hypertension, however, occurred more frequently in the study group than in the control group (P less than .001). These data could be helpful in counseling women with repeated pregnancy loss.

The antenatal sonographic visualization of cloacal dysgenesis.

Hydronephrosis associated with a septated cystic structure in the fetal pelvis in the absence of an otherwise identifiable fetal bladder should alert the sonographer to the possibility of a persistent cloaca. Problems associated with compromised urinary tract drainage and the associated oligohydramnios occurring early in gestation as well as frequent association of anomalies with other organ systems must be addressed. Squamous epithelia in fetal bladder aspirate is further supportive evidence for the diagnosis.

Prenatal ultrasonic diagnosis of multiple bowel atresias.

This case illustrates the course of an obstructive process through spontaneous perforation resulting in decompression of dilated bowel loops. The resulting meconium peritonitis appeared as fetal ascites. Postnatal investigations and laparotomy confirmed the diagnosis of a rare form of multiple congenital atresias of the bowel.

Biochemical examination of fetal skin biopsy specimens obtained by fetoscopy: use of the method for analysis of keratins and filaggrin.

This paper describes a method for biochemical analysis of proteins from fetal skin biopsy samples. The method has wide potential application for diagnosis of disorders with a known protein abnormality detectable by protein staining or a specific antibody. Analysis requires a single 1 mm biopsy, is rapid (2 days) and extremely sensitive. In the present study, fetal skin biopsies from normal fetuses and a fetus at risk for lamellar ichthyosis were obtained. The epidermis or hairs with attached follicular cells were dissected from the remaining skin. Proteins were extracted and separated by SDS-polyacrylamide gel electrophoresis. Proteins from duplicate gels were transferred to nitrocellulose and immunostained for the acidic and basic keratins and for the keratin filament associated protein, filaggrin, using monoclonal antibodies. All samples contained keratins typical of fetal epidermis at 20 weeks gestation. Presence of filaggrin is variable at this age and depends on the presence of keratinized cells of hair canals. No keratin abnormalities in the fetus at risk for lamellar ichthyosis were detected, however, in one presumably normal biopsy, an abnormally low proportion of the 67 kd keratin and the presence of follicular keratins were evident. These results demonstrate that biochemical analysis of fetal biopsies is possible, thus increasing the diagnostic potential of the fetal biopsy procedure for disorders in which a known protein or antigen is altered in utero.

Ovulation induction by human menopausal gonadotropin with ultrasonic monitoring of the ovarian follicles.

One hundred sixteen cycles of human menopausal gonadotropin (hMG) treatment for ovulation induction were studied. The ovarian response to hMG treatment was monitored by the daily determination of serum estradiol (E2) or by daily serum E2 and repeated ultrasonic examination of the ovaries. There were more follicles 18 mm in diameter or larger at the time of human chorionic gonadotropin (hCG) administration in the pregnancy than in the non-pregnancy cycles, and in the hyperstimulated than in the nonhyperstimulated cycles. The ovulatory rate and the pregnancy rate per cycle did not improve with the use of ultrasound. The number of treatment cycles required to achieve pregnancy was less in patients who had ultrasonic examination of the ovarian follicles. These results suggest that ultrasonic examination of the ovarian follicle helps to reduce the number of hMG cycles required to achieve pregnancy. The development of multiple follicles results in more pregnancies. However, the use of ultrasound does not improve the pregnancy rate.

Prenatal diagnosis of hemoglobinopathies: evaluation of techniques for analysing globin-chain synthesis in blood samples obtained by fetoscopy.

Three techniques for analysing hemoglobin synthesis in blood samples obtained by fetoscopy were evaluated. Of the fetuses studied, 12 were not at risk of genetic disorders, 10 were at risk of beta-thalassemia, 2 were at risk of sickle cell anemia and 1 was at risk of both diseases. The conventional method of prenatal diagnosis of hemoglobinopathies, involving the separation of globin chains labelled with a radioactive isotope on carboxymethyl cellulose (CMC) columns, was compared with a method involving globin-chain separation by high-pressure liquid chromatography (HPLC) and with direct analysis of labelled hemoglobin tetramers obtained from cell lysates by chromatography on ion-exchange columns. The last method is technically the simplest and can be used for diagnosing beta-thalassemia and sickle cell anemia. However, it gives spuriously high levels of adult hemoglobin in samples containing nonlabelled adult hemoglobin. HPLC is the fastest method for prenatal diagnosis of beta-thalassemia and may prove as reliable as the CMC method. Of the 13 fetuses at risk for hemoglobinopathies, 1 was predicted to be affected, and the diagnosis was confirmed in the abortus. Of 12 predicted to be unaffected, 1 was aborted spontaneously and was unavailable for confirmatory studies, as were 3 of the infants; however, the diagnosis was confirmed in seven cases and is awaiting confirmation when the infant in 6 months old in one case. Couples at risk of bearing a child with a hemoglobinopathy should be referred for genetic counselling before pregnancy or, at the latest, by the 12th week of gestation so that prenatal diagnosis can be attempted by amniocentesis, safer procedure, with restriction endonuclease analysis of the amniotic fluid cells.

Chorionic villi sampling: clinical experience, immediate complications, and patient attitudes.

To develop chorionic villi sampling as a procedure for prenatal diagnosis, a pilot study was undertaken to perfect the obstetric and laboratory techniques, to evaluate our success with the procedure in continuing pregnancies, and to assess the attitudes of potential users of the procedure. Women about to have elective first-trimester abortions for nongenetic reasons were enrolled in the first phase of the study. Of the patients with a positive pregnancy test, 12.4% were found to have a nonviable pregnancy on ultrasound examination. Samples adequate for cytogenetic analysis were obtained in 130 of the 155 remaining cases, and the success rate was 93% in the 100 most recent cases. Direct cytogenetic analysis was undertaken in those cases successfully sampled, and karyotypes could be prepared in 97%. Immediate complications occurred in 5% of the pregnancies. Eight women at risk of bearing a child with a genetic defect had diagnostic chorionic villi sampling. Cytogenetic analysis was performed successfully on all of them. One had an induced abortion following the procedure because of the fetal diagnosis (a male with a 50% risk of Duchenne's muscular dystrophy). The other pregnancies are continuing uneventfully at 22 to 35 weeks' gestation. Finally, from preliminary analysis of our survey of potential users it appears that women 35 years old or over would prefer chorionic villi sampling to amniocentesis if the risks of the sampling were known to be low.

How small is too small in a twin pregnancy?

OBJECTIVE: The objective was to determine whether small twins had a survival advantage with respect to small singletons after controlling for other factors associated with adverse perinatal outcome. STUDY DESIGN: A hospital-based cohort study included all births between 1980 and 1995 of babies born between 24 and 43 weeks' gestation. Logistic regression was used to estimate the perinatal mortality risks for monochorionic and dichorionic twins with growth restriction after adjusting for gestational age, maternal age, parity, method of delivery, and the presence or absence of congenital malformations. RESULTS: The study sample included 1062 dichorionic twins, 354 monochorionic twins, and 59,873 singletons. Small monochorionic and dichorionic twins showed a similar overall risk of perinatal mortality (odds ratio 1.40, confidence interval 0.86 to 2.25). However, monochorionic twins with birth weights <10th percentile faced an increased risk of perinatal death compared with singletons (odds ratio 2.45, confidence interval 1.20 to 5.02). Dichorionic twins had no such increased risk (odds ratio 0.91, confidence interval 0.45 to 1.84). CONCLUSIONS: Twins with growth restriction are not protected against perinatal loss, even after adjusting for congenital malformations. In fact, monochorionic twins are more than twice as likely to die in the perinatal period as are their singleton counterparts.

Dystocia among women with symptomatic uterine rupture.

OBJECTIVE: The purpose of this study was to analyze cervical dilatation patterns among women with uterine rupture by means of a mathematic model and to use the results to determine optimal intervention criteria. STUDY DESIGN: This was a case-control review that compared a case patient group of 19 women with uterine rupture during labor with control groups with either no previous cesarean deliveries, vaginal birth after cesarean delivery, or failure of attempted vaginal birth after cesarean delivery. The mathematic model quantified dilatation and adjusted for conditions specific to each patient. Case patients were compared with matched control subjects by means of paired t tests, analysis of variance, odds ratios, and conditional logistic regression. RESULTS: Dystocia was present in 31.6% to 47.4% of patients with uterine rupture, versus 2.6% to 13.2% of the control group with no previous cesarean deliveries (P< or =.001). The incidence of an arrest disorder among patients with uterine rupture was similar to that seen in the control group with failure of attempted vaginal birth after cesarean delivery. However, the interval from diagnosis to rupture or cesarean delivery was 5.5 +/- 3.3 hours among case patients with uterine rupture and 1.5 +/- 1.3 hours in the control group with failure of attempted vaginal birth after cesarean delivery. CONCLUSION: When cervical dilatation was lower than the 10th percentile and was arrested for > or =2 hours, cesarean delivery would have prevented 42.1% of the cases of uterine rupture and resulted in excess 2.6% and 7.9% cesarean delivery rates among women with no previous cesarean deliveries and women with vaginal birth after cesarean delivery, respectively.

Prenatal diagnosis of congenital non-bullous ichthyosiform erythroderma (lamellar ichthyosis).

We report the first positive prenatal diagnosis of congenital non-bullous ichthyosiform erythroderma or lamellar ichthyosis. Fetal skin samples were obtained by fetoscopy at 21 weeks' gestation and examined by light and electron microscopy. Light microscopy revealed a thickened interfollicular epidermis with multiple layers of flattened cells and excessive keratinization of the epidermal lining of the follicular infundibulum. Electron microscopy of the thickened epidermis revealed granular cells that contained larger-than-normal keratohyalin granules and multiple layers of parakeratotic cornified cells. Although there was regional variation in the degree of interfollicular keratinization, follicles from all regions showed greater and more complete keratinization, indicating that they express the abnormality early enough in development to permit prenatal diagnosis at about 20 weeks' gestation.

Fetal cephalometry by ultrasound as a screening procedure for the prenatal detection of Down's syndrome.

Infants and children with Down's syndrome have a cephalic index (ratio of biparietal to occipitofrontal diameter) higher than that in normal children. To determine whether this difference is present and detectable by ultrasound measurement of the second-trimester fetal head, we calculated the cephalic indices for 308 normal fetuses and eight fetuses with a 47, +21 karyotype. The mean cephalic index in the fetuses with Down's syndrome (0.829, SD 0.033) was indistinguishable from that in the normal fetuses (0.825, SD 0.042). These data suggest that the documented difference in mean cephalic index between liveborn children with Down's syndrome and normal control children is not detectable in the mid-gestation fetus and that ultrasound cephalometry alone is unlikely to discriminate reliably between normal and affected fetuses.

Maternal asthma and idiopathic preterm labor.

Previous studies suggest that women with asthma are at increased risk of preterm birth. Moreover, drugs (especially beta-agonists) used to treat asthma are also used to treat preterm labor. The authors carried out a case-control study of 555 women from three hospital centers with idiopathic preterm labor (< 37 weeks), including two overlapping (i.e., non-mutually exclusive) subsamples: cases with early idiopathic preterm labor (< 34 weeks) and cases with idiopathic recurrent preterm labor (< 37 weeks plus a previous history of preterm delivery or second-trimester miscarriage). Controls were matched to cases according to race and smoking history prior to and during pregnancy. All subjects responded in person to questions about atopic, respiratory, obstetric, and sociodemographic histories. Subjects in the early and recurrent preterm labor subsamples were also asked to undergo spirometric testing with methacholine challenge 6-12 weeks after delivery. Cases were significantly more likely to report histories of asthma symptoms and physician-diagnosed asthma (matched odds ratios of 2-3) than controls, particularly those cases with recurrent preterm labor. No significant associations were observed, however, with methacholine responsiveness. These results could not be explained by residual confounding by smoking or other variables, nor by selective recall of asthma symptoms and histories by cases. Women with asthma are at increased risk of idiopathic preterm labor. The fact that no such association was seen with methacholine responsiveness suggests that nonatopic, noncholinergic mechanisms may link bronchial and uterine smooth muscle lability.