Expression of amyloid precursor protein (beta-APP) in the neonatal brain following hypoxic ischaemic injury

Perinatal hypoxic ischaemic brain injury (HII) is a major cause of neonatal mortality and long-term neurological morbidity. An understanding of the molecular events which follow HII may lead to novel treatments to improve the final outcome for affected infants. The beta-amyloid precursor protein (beta-APP) is a widely expressed transmembrane protein whose proposed functions include stabilization of neuronal calcium fluxes, inhibition of the clotting cascade and cell-cell or cell-matrix adhesion. Normally present at low levels in neurons its expression is induced as part of the acute response of the adult brain to HII. This study aimed to determine whether beta-APP is also part of the acute adaptive response of the infant brain to HII. Immunohistochemistry and Western blotting were used to assess cerebral beta-APP expression in 14-day-old rat pups subjected to unilateral HII, and in 10 term human infants, who died between 12 h and 16 months after severe perinatal HII. In the rat pups beta-APP expression was increased by 2 h post-injury, peaked, fourfold above control levels, at 24 h and gradually declined over the following 4 days. Expression was induced bilaterally, but was greater on the side of injury. In the human infants, increased, predominantly neuronal expression of beta-APP, was detectable immunohistochemically within 24 h of injury and was greatest in those infants dying within 3 days. Expression was particularly strong in the areas showing histological evidence of injury, but was also seen in apparently undamaged areas. We conclude that beta-APP induction is part of the the acute adaptive response of the neonatal brain to HII.

Abdominal circumference in fetuses with congenital diaphragmatic hernia: correlation with hernia content and pregnancy outcome

To assess the value of abdominal circumference measurements in the second trimester as a predictor of mortality in fetuses with congenital diaphragmatic hernia, 34 fetuses with this condition who had had second trimester ultrasonographic evaluation were analyzed retrospectively for abdominal circumference measurements, content of the hernia, and pregnancy outcome. The abdominal circumference was below the fifth percentile in nine of the 27 fetuses (33%) with an isolated defect and in five of the seven fetuses (71%) with additional anomalies. In fetuses with isolated congenital diaphragmatic hernia, an abdominal circumference measurement below the fifth percentile was associated with the presence of the liver (P < 0.05) but not of the stomach in the chest. In 19 continuing pregnancies with an isolated defect, all five fetuses with an abdominal circumference below the fifth percentile either died prenatally (n = 1), soon after birth (n = 1), or after surgery (n = 3). In contrast, only six of the 14 fetuses (43%) with an abdominal circumference measurement within the normal range died, either soon after birth (n = 2) or after surgery (n = 4) (P < 0.05). We conclude that an abdominal circumference measurement below the fifth percentile in the second trimester appears to be a good predictor of a poor prognosis in fetuses with congenital diaphragmatic hernia.

VACTERL with hydrocephalus in twins due to Fanconi anemia (FA): mutation in the FAC gene

We present a dizygotic twin pair each with ventriculomegaly, a radial ray defect and multiple malformations in keeping with the VACTERL association. Molecular studies demonstrated that both are homozygous for IVS4 + 4 A-->T, a mutation in the Fanconi anemia complementation group C gene. This is the first molecular proof that VACTERL with hydrocephalus may be the result of severe Fanconi anemia.

High failure rate of postmortem karyotyping after termination for fetal abnormality

OBJECTIVE

To determine the failure rate of karyotyping from samples taken after termination of pregnancy for fetal abnormality.

METHODS

Perinatal autopsy reports over a 12-month period were reviewed to identify those with cytogenetic studies performed after termination of pregnancy for fetal abnormality.

RESULTS

During the audit period, there were 104 terminations for fetal abnormality. In 89 fetuses, fetal skin (n = 85), placenta (n = 62), or other samples (n = 8) were obtained for postmortem cytogenetic analysis. In 24 (27%) fetuses, postmortem tissues did not yield a karyotype result. The failure rate of post-termination karyotyping was significantly influenced by delivery-sampling interval, but not by gestational age, type of tissue sampled, use of potassium chloride, or aneuploidy. Of the 24 cases for which no post-termination karyotype was obtained, 16 had had successful pre-termination karyotyping, resulting in only eight of 89 (9%) cases in the overall series not having a final karyotype.

CONCLUSION

The high failure rate for post-termination karyotyping suggests that a pre-termination procedure is necessary if parents wish to have almost 100% certainty that cytogenetic information will be available for later genetic counseling.

Glioependymal and arachnoid cysts: unusual causes of early ventriculomegaly in utero

In this report we describe two cases of fetal midline intracranial cyst presenting with ventriculomegaly at routine detailed second-trimester scan. In the first case, additional findings included a banana-shaped hypoplastic cerebellum and macrocephaly; autopsy after termination of the pregnancy revealed a glioependymal cyst. In the second case, subsequent follow-up examination revealed a progressive increase in cyst size and worsening of ventriculomegaly; termination of pregnancy was performed at 24 weeks and autopsy confirmed an arachnoid cyst. These cases document interhemispheric cyst as a cause for early ventriculomegaly in utero.

Plaque abrasion and intra-aortic balloon leak

STUDY OBJECTIVE

To determine and correct cause of high incidence of intra-aortic balloon leaks (ruptures).

DESIGN

Epidemiologic investigation of factors associated with intra-aortic balloon leak, and sequential application of corrective measures evaluated by continued concurrent data collection.

SETTING

Thirty-four-bed ICU in 598-bed tertiary care medical center.

INTERVENTIONS

Procedure changed to place smaller balloons (34 mL instead of 40 mL) in patients less than 163 cm in height.

MEASUREMENTS AND RESULTS

Demographic and clinical data on all patients showed no change after initial interventions, followed by significant drop (8 to 2%) in incidence of balloon leak when smaller, shorter balloons were placed in shorter patients.

CONCLUSIONS

Placement of larger, longer balloons in patients increases risk of perforation of balloon by calcific plaque in the distal thoracic and abdominal aorta.

Prenatal findings in generalized amyoplasia

Amyoplasia is a rare, sporadic condition characterized by different degrees of maldevelopment of the skeletal muscles, which are replaced by fibrous and fatty tissue. In this report, we present a case of generalized amyoplasia presenting at 19 weeks' gestation. The most striking finding was the absence of fetal movements, resulting in severe multiple congenital contractures, hydrops, and polyhydramnios. At autopsy, histological examination of the skeletal muscle showed small groups of poorly developed fibres within areas of fat. This report suggests that generalized amyoplasia could be a common cause of severe forms of multiple congenital contractures, but is probably underdiagnosed at post-mortem because of inadequate examination of muscles. Definitive diagnosis is important in determining the risks of recurrence in these cases.

Continuous infusion of haloperidol controls agitation in critically ill patients

OBJECTIVE

To evaluate the safety and efficacy of continuous infusion of haloperidol in treating agitated critically ill adult patients.

DESIGN

Case series of patients treated with continuous infusion of haloperidol and followed to hospital discharge, during a 6-month period.

SETTING

A 34-bed multidisciplinary intensive care unit (ICU) in a 598-bed nonuniversity, tertiary care teaching hospital.

PATIENTS

Consecutive sample of eight patients requiring mechanical ventilation who had severe agitation which was refractory to intermittent bolus treatment with benzodiazepines, narcotics, and haloperidol.

INTERVENTIONS

Continuous infusions of haloperidol (range 3 to 25 mg/hr) were supplemented, as required, to maintain adequate sedation.

MEASUREMENTS AND MAIN RESULTS

The four men and four women averaged 47 yrs of age, and the average length of hospitalization was 33 days, with 25 days spent in the ICU. On the day continuous infusion of haloperidol was initiated, the average Acute Physiology and Chronic Health Evaluation (APACHE) II and Therapeutic Intervention Scoring System (TISS) scores were 24 and 47, respectively. The Sedation-Agitation Scale score averaged +2.4 (maximum agitation score being +3) before continuous infusion of haloperidol decreasing to +1.8 after 1 day (p = .38) and to +0.8 after 2 days (p = .06) of continuous infusion of haloperidol. The average daily haloperidol dose increased from 68 mg before continuous infusion of haloperidol to 269 mg (p < .008) after 1 day. The daily total of nonhaloperidol sedatives decreased from 18.3 to 10.9 sedation-equivalent units (p = .15) and the daily number of bolus administrations of sedatives decreased from 23 to 7 (p = .01) after 1 day of continuous infusion of haloperidol. Estimated nursing time to prepare, administer, and monitor these bolus medications decreased from 320 to 96 mins per 24 hrs (p = .01). Of the five patients discharged alive (37.5% mortality rate), four were successfully weaned from assisted ventilation during continuous infusion of haloperidol. Two of these four patients were difficult to wean because of agitation and oversedation. Four possible complications were noted: minor tremors (n = 2), atrial dysrhythmias with intermittent third-degree atrioventricular block and QT interval prolongation (n = 1), and ventricular tachycardia (n = 1).

CONCLUSIONS

Continuous infusion of haloperidol effectively controls severe agitation in critically ill patients, reduces requirements for bolus administration of sedatives and nursing time lost to that task, and may facilitate ventilator weaning. Parenteral administration of haloperidol was associated with few complications in > 1,340 patient-hours of continuous administration.

Differential changes in serum concentrations of androgens and estrogens (in relation with cortisol) in postmenopausal women with acute illness

Previous studies of adrenal androgens and estrogens in critical illness were limited by measuring only selected sex steroids and by including men (who have confounding simultaneous changes in gonadal steroids). We evaluated relationships between changes in serum levels of cortisol (F), androgens, estrogens, and gonadotropins in 20 postmenopausal women with acute critical illness to determine if changes in adrenal androgens and estrogens paralleled gonadal axis suppression or adrenal stimulation. Two patterns of changes in sex steroids were observed. Admission serum levels of androstenedione (delta 4-A), estradiol, and estrone, like F, were increased compared to healthy controls (P < 0.0001). delta 4-A and estrone then decreased toward normal by day 5 in parallel with cortisol (r = 0.56 and 0.60). In contrast, admission serum dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEA-S) were not elevated and testosterone (T) was decreased in our patients compared to controls (P < 0.0005) in parallel with serum gonadotropin levels. Serum levels of DHEA and T continued to decrease by day 5 in parallel with gonadotropins. We conclude that in agonadal patients with acute critical illness, serum levels of DHEA-S and T are selectively decreased in relation to F, delta 4-A, and estrogens. The decreased serum T levels suggest inhibition of 17 beta-OH-dehydrogenase and/or increased aromatization to estradiol. The marked increase in serum estrogen levels also suggests increased aromatization. The absence of increases in DHEA and DHEA-S suggest enhanced activity of 3 beta-hydroxysteroid dehydrogenase and/or inhibition of C17,20-lyase activity of P-450c17. The clinical significance of this marked increase in the ratio of estrogens to androgens in acute illness requires further investigation.

Primary malignant melanoma of the rectum

The diagnosis of a primary rectal malignant melanoma has been the subject of considerable argument for many years, principally on the grounds that extension from a primary anal lesion was often impossible to exclude. This paper provides evidence that certain melanomas can be recognized as primary rectal tumours, not only from careful anatomical assessment of the site of the tumour, but also by showing that they arise on a background of benign melanocytic proliferation in the rectal mucosa. The clinical presentation of these lesions, their possible mechanism of origin and their treatment is discussed.

An ATF/CREB binding motif is required for aberrant constitutive expression of the MHC class II DR alpha promoter and activation by SV40 T-antigen

Constitutive expression of major histocompatibility complex class II (MHC II) antigens normally occurs in B-lymphocytes and antigen presenting cells of the monocyte/macrophage lineage. However, many malignant tumours and transformed cells express these proteins aberrantly. We demonstrate here that the MHC II DR alpha promoter is constitutively active both in the SV40 large T antigen transformed cell line, COS, and in CV1 cells from which they are derived. As an approach to understanding the molecular mechanisms underlying aberrant DR alpha expression we have examined the cis- and trans-acting requirements for DR alpha transcription in these cell types. Electrophoretic mobility shift assays showed that the region immediately 3' to the X-box was bound by a member of the ATF/CREB family of transcription factors. Using deletions and point mutations in the DR alpha promoter we demonstrate that, in contrast to B-cells, the octamer motif and conserved X- and Y-boxes make only a minor contribution to promoter function while single point mutations in the ATF/CREB motif reduced transcription up to 20-fold. In addition, we show that the DR alpha promoter is activated by SV40 large T-antigen and that activation requires an intact ATF/CREB motif. Similar data were obtained using B16 melanoma cells. These results suggest that the ATF/CREB motif may be a target for transcription deregulation in several transformed cell types.

Transcription and cancer

The normal growth, development and function of an organism requires precise and co-ordinated control of gene expression. A major part of this control is exerted by regulating messenger RNA (mRNA) production and involves complex interactions between an array of transcriptionally active proteins and specific regulatory DNA sequences. The combination of such proteins and DNA sequences is specific for given gene or group of genes in a particular cell type and the proteins regulating the same gene may vary between cell types. In addition the expression or activity of these regulatory proteins may be modified depending on the state of differentiation of a cell or in response to an external stimulus. Thus, the differentiation of embryonic cells into diverse tissues is achieved and the mature structure and function of the organism is maintained. This review focusses on the role of perturbations of these transcriptional controls in neoplasia. Deregulation of transcription may result in the failure to express genes responsible for cellular differentiation, or alternatively, in the transcription of genes involved in cell division, through the inappropriate expression or activation of positively acting transcription factors and nuclear oncogenes. Whether the biochemical abnormalities that lead to the disordered growth and differentiation of a malignant tumour affect cell surface receptors, membrane or cytoplasmic signalling proteins or nuclear transcription factors, the end result is the inappropriate expression of some genes and failure to express others. Current research is starting to elucidate which of the elements of this complicated system are important in neoplasia.

Oncocytoma of the larynx

A case of oncocytoma of the larynx is presented. These lesions are rarely found in the larynx, and have been more commonly described in the salivary and thyroid glands. The histopathological diagnosis is often difficult and the light microscopy can be unreliable for oncocytic lesions. For a more accurate definition of these tumours, the use of histochemical stains together with electron microscopy are advocated. With adequate surgery, the prognosis is excellent, and tumours are unlikely to recur. This paper discusses the management of a patient with a benign oncocytoma of the true vocal cord, and presents a review of the world literature.

Repopulation of guinea-pig skin by melanocytes during wound healing: a morphometric study

Epidermal keratinocytes and melanocytes have a close functional interrelationship. In order to study this relationship we used computer-assisted three-dimensional morphometry (CAM) to investigate the shape and size changes of the cutaneous melanocyte in healing guinea-pig skin. The combination of CAM with osmium iodide staining and resin embedding of tissue gave excellent results and allowed qualitative and quantitative morphometric assessment of melanocytes in vertical epidermal sections. The changes in melanocytes and keratinocytes during healing of a standard 1 cm full thickness wound in the guinea-pig were studied. After an initial decrease, more melanocytes per mm2 of epidermis were seen (from 36 days). These were smaller in volume with shorter, less branched dendrites compared to controls. An unexpected finding was a late phase of melanocyte proliferation, at the end of our study period (99 days). Clearly, the complex changes in the melanocyte-keratinocyte relationship during wound healing continue throughout and beyond the period of our study.

Primary malignant melanoma of the lung

Primary malignant melanoma of the lung is a rare neoplasm; to date, there have been approximately 20 cases reported in the literature. Extensive clinical and postmortem examinations are necessary to exclude the possibility that the lung tumor does not represent a metastasis from an occult cutaneous or extracutaneous melanoma. We present a case of a 62-yr-old man who appears to have had a primary melanoma of the left upper lobe of the lung. The literature on primary pulmonary melanoma is also reviewed.

Cerebellar cortical degeneration in association with small-cell carcinoma of the oesophagus

We report the association of paraneoplastic cerebellar cortical degeneration with small-cell oesophageal carcinoma in a 60-year-old woman and describe the histopathological findings. We believe this to be the first report of such an occurrence. The cytoplasmic antigen PGP 9.5, which is strongly expressed in cerebellar Purkinje cells, was identified immunohistologically in the primary tumour and immunoglobulin demonstrated on Purkinje cells. These findings support an immunological pathogenesis for this condition and suggest that it is mediated by antibodies directed against tumour antigen which cross-react with Purkinje cells.

A distinct octamer-binding protein present in malignant melanoma cells

The octamer-binding proteins present in HeLa cells, B-cells and malignant melanoma cells were compared by a gel-electrophoresis DNA-binding assay. Using an extract from the malignant melanoma cells a complex was formed using a variety of octamer containing probes that was distinct from those found using either a HeLa or B-cell extract. DNAase 1 footprints and methylation interference patterns of the melanoma-specific octamer-binding protein were indistinguishable from those obtained with the HeLa factor NF-A1, except for preferential binding of the melanoma-specific factor to DNA methylated at two G residues 16 base-pairs 3' to the octamer motif. Competition analyses using a variety of wild-type and mutant probes showed that mutations affecting binding of NF-A1 similarly affected binding of the melanoma octamer-binding factor. These data also revealed the extreme flexibility of the octamer-binding site, with one probe sharing only 4 bases with the 8 base consensus sequence binding efficiently.

Survival in complicated diphenhydramine overdose

This report describes the first case of an adult to survive all the major complications of diphenhydramine hydrochloride overdose, including hyperpyrexia, status epilepticus, coma, and cardiac arrhythmias. Physostigmine appeared to be of benefit in reversing these abnormalities in combination with other therapies.

Cardiac injury after chest trauma

Fifty consecutive patients with severe chest trauma were studied prospectively to evaluate the frequency of significant cardiac injury and to determine what diagnostic studies were useful. Forty-nine of 50 patients had elevated cardiac enzymes and 26 of 50 had abnormal ECGs on admission. No patient had complications associated with myocardial infarction, including 15 who underwent general anesthesia. We found persistent (greater than 48 h) ECG changes in only 3, 2 of these 3 also had markedly elevated MB fraction of CPK. Significant pericarditis occurred in 5 patients, 2 of whom never had ECG abnormalities. We conclude that minor cardiac injury is common in severe chest trauma, but only rarely causes myocardial contusion. Myocardial isoenzymes may be useful in making that important distinction. Clinically significant traumatic pericarditis may occur in the absence of ECG changes and must be considered in every patient with chest injury and unstable hemodynamics.