Inheritance of chromosome 7 is associated with a drug-resistant phenotype in somatic cell hybrids

A major form of drug resistance in tumour cells known as classical multidrug resistance (MDR) is associated with the overexpression of the mdr1 gene product, the membrane protein P-glycoprotein (P-gp), which acts as an energy-dependent drug efflux pump. In this study the inheritance of P-gp expression was examined using hybrids formed after somatic cell fusion between a drug-sensitive human T-cell leukaemia cell line, CEM/CCRF, and a drug-resistant derivative, CEM/A7, which is characterized by a clonal chromosomal duplication dup(7)(q11.23q31.2). Fourteen hybrids, chosen at random, were analysed by reverse transcriptase-polymerase chain reaction (RT-PCR) and by binding studies involving the monoclonal antibody MRK16, which recognises an external P-gp epitope. Only two hybrids were positive for both MRK16 antibody labelling and mdr1 mRNA. Partial karyotypic analysis of all hybrids revealed that only the MRK16-positive hybrids contained the duplication in chromosome 7 seen in the CEM/A7 parental MDR line. Therefore, P-gp overexpression in the MRK16-positive hybrids may be linked to the inheritance of chromosome 7 from CEM/A7 and possibly associated with the chromosome 7 abnormality.

Nodular fasciitis of the nose in a child

Nodular fasciitis is an unusual benign tumour composed of fibroblasts. It presents as a rapidly growing mass arising from subcutaneous or deep fascia. Less than 20% of cases occur in children. Diagnosis can only be made by histopathological examination of a biopsy of the lesion. A case of nodular fasciitis presenting as a mass arising from the right nasal cavity in a 19-month-old female is presented. The lesion was successfully eradicated by surgical removal. There has been no recurrence at 4-year review. Nodular fasciitis is a benign condition that may mimic malignancy clinically and histologically. Recognition of this condition is important to avoid unnecessarily aggressive treatment. Relevant clinical, radiological and histological features are discussed.

Neuropsychological function and MRI abnormalities in neurofibromatosis type 1

This study investigated the relationship between MRI abnormalities and cognitive function in neurofibromatosis type 1.40 children aged eight to 16 years underwent comprehensive neuropsychological, medical and neuroradiological assessments. MRI scans revealed a characteristic pattern of T2-weighted signals ('UBOs') located primarily in the basal ganglia, brainstem and cerebellum in 25 of the children. Reductions in global IQ, attention, and visuopatial and executive functions were shown to occur in association with the presence of UBOs. These findings establish a link between changes in neuropsychological functions and MRI abnormalities in NF-1, and further support neuropathological findings which suggest that UBOs may be a manifestation of delayed or disordered myelination.

Reducing donor exposure in preterm infants requiring multiple blood transfusions

Preterm infants frequently require multiple blood transfusions. Traditionally, 'fresh' (less than seven days old) blood has been used but this often results in transfusions from multiple donors. To reduce donor exposure the policy for top-up transfusions was changed. A unit of blood under five days old with additional satellite packs was ordered for each infant and used up to its expiry date, allowing up to eight transfusions from a single donation to be given. The mean (SD) number of transfusions per infant in 43 infants transfused according to previous policy and in 29 transfused according to the new policy was similar at 5.6 (4.0) and 5.3 (3.1), respectively. However, donor exposure fell following the change in policy from 4.9 (3.5) to only 2.0 (0.9). Only one infant was exposed to more than three donors compared with 24 infants in the control group. Plasma potassium concentrations were not significantly different following transfusion of blood stored for up to 33 days. This simple change in policy has reduced donor exposure in infants requiring multiple top-up transfusions.

Specific learning disability in children with neurofibromatosis type 1: significance of MRI abnormalities

To determine whether previously reported areas of increased T2 signal intensity on MRI examination in children with neurofibromatosis type 1 (NF 1) are associated with deficits in development and learning common in this population, we evaluated 51 children with NF 1 (aged 8 to 16 years). Forty children completed the full assessment protocol (MRI, medical, psychometric, speech therapy, and occupational therapy assessments). The mean Full Scale IQ scores for the entire study population showed a left shift compared with the normal population, and the distribution of IQ scores was bimodal, suggesting that there are two populations of patients with NF 1--those with and those without a variable degree of cognitive impairment. There was no association between lower IQ scores and any clinical variable. Areas of increased T2 signal intensity unidentified bright objects (UBO+) were present in 62.5% of the study population, and their presence was not related to clinical severity, sex, age, socioeconomic status, macrocephaly, or family history of NF 1. However, compared with children without areas of increased T2 signal intensity (UBO-), the UBO+ group had significantly lower mean values for IQ and language scores and significantly impaired visuomotor integration and coordination. Children with areas of increased T2 signal intensity were at a much higher risk for impaired academic achievement. Children without increased T2 signal on MRI (UBO-) did not significantly differ from the general population in any measure of ability or performance. Areas of increased T2 signal on MRI represent dysplastic glial proliferation and aberrant myelination in the developing brain and are associated with deficits in higher cognitive function.(ABSTRACT TRUNCATED AT 250 WORDS)

Sclerosing cholangitis in children with inflammatory bowel disease

BACKGROUND

Primary sclerosing cholangitis (PSC) with inflammatory bowel disease (IBD) has been rarely reported in children.

AIM

To describe the clinical presentation, sequential liver function test abnormalities, radiological bile duct anomalies and liver histology in four children with PSC and IBD.

METHODS

Over a period of 18 years, four of 130 patients with IBD developed abnormal liver function tests. Three of the four patients had ulcerative colitis and the other Crohn's disease. All four patients had baseline and follow-up liver function tests, percutaneous transhepatic cholangiography and a needle biopsy of the liver.

RESULTS

The four patients at presentation had minimal symptoms or signs of liver disease. All had elevation of serum transaminases, gamma glutamyl transferase and/or alkaline phosphatase. Three had the typical onion skin fibrosis of bile ducts. Percutaneous transhepatic cholangiography demonstrated irregularity and beading of the hepatic and common bile ducts in three patients. The other with normal cholangiography had fibrosing cholangitis on liver biopsy and was considered to have small duct disease.

CONCLUSIONS

We conclude that yearly biochemical assessment of liver function should be performed on all children with IBD, and if abnormal should raise the suspicion of PSC. The latter diagnosis can be confirmed by liver biopsy and cholangiography.

Hemiplegia due to posterior cerebral artery occlusion

BACKGROUND

Hemiplegia is a rare manifestation of posterior cerebral artery occlusion. The acute clinical picture may be difficult to differentiate from occlusion of the middle cerebral artery. A mechanism for the hemiplegia has not been conclusively determined.

CASE DESCRIPTION

We describe a patient with hemiplegia secondary to posterior cerebral artery occlusion by an embolized fragment of a prosthetic valve. Computed tomographic scan showed the foreign body just distal to the origin of the posterior cerebral artery with infarction of its vascular territory. These findings were later confirmed at autopsy. There was no radiological or autopsy evidence of involvement of the other cerebral arteries or their territories.

CONCLUSIONS

The patient provides further evidence that occlusion of the posterior cerebral artery just distal to its junction with the posterior communicating artery may produce contralateral hemiplegia without oculomotor nerve nucleus involvement.

Chronic motor neuron disease possibly related to intoxication with organochlorine insecticides

We report on two patients with a history of chronic exposure to organochlorine insecticides who developed clinical and electromyographic signs and symptoms of chronic motor neuron disease. Measurements of aldrin, lindane and heptachlor confirmed the intoxication. We emphasize the importance of searching for toxic and environmental factors in cases of motor neuron disease especially in Third World countries, where workers usually wear no adequate protective equipment.

Selective inhibition of luteinizing hormone action by ethanol in cultured human granulosa cells

To extend further our previous observations on the inhibition of luteinizing hormone (LH)-induced increases in steroid secretion by ethanol (EtOH) (Alcohol. Clin. Exp. Res. 14:522-527, 1990), cultured human granulosa cells were pretreated with several EtOH concentrations (0-100 mM), and cells were stimulated with human LH (25 ng/ml) or human follicle stimulating hormone (FSH) (100 ng/ml) and the secretion of 17-beta-estradiol (E2) and progesterone (P) was measured. EtOH significantly increased basal E2 secretion in a dose-related manner (0-20 mM); however, in the same concentration range EtOH did not produce consistent changes in FSH-stimulated E2 secretion. In contrast, EtOH decreased LH-stimulated E2 secretion between 0-20 mM such that at 20 mM EtOH, the positive effect of LH was abolished. EtOH increased P secretion by 40% at 20 mM and at 100 mM, there was a 100% increase. The FSH-stimulated P secretion was not consistently changed by EtOH, whereas LH-stimulated P secretion was decreased in a dose-dependent manner. LH/human chorionic gonadotropin (hCG) receptors in cells exposed to EtOH showed a 15% (p < 0.01) and a 47% decrease at 20 mM and 50 mM EtOH, respectively. At 50 mM EtOH, there was a decrease in LH/hCG receptor number from 2900/cell to 1670/cell, without a change in receptor affinity for hCG and 50 mM EtOH decreased LH/hCG receptors in intact granulosa cells in a time-dependent manner. These results indicate that the selective effects of EtOH on LH action in human granulosa cells may be mediated in part by an action on LH/hCG receptors.

Development of non-Rh antibodies in volunteers stimulated for the production of hyperimmune anti-D

At the North London Blood Transfusion Centre, red cells from accredited Rh-D-positive donors, matched for all antigens capable of inducing clinically significant antibodies, are used to stimulate immune plasma donors to achieve higher anti-D levels. Despite such careful matching, antibody to the relatively non-immunogenic M antigen developed in 3 out of 20 NN donors (15%) stimulated with M-positive cells. In general, good responders to the Rh antigen D are good responders to other red cell antigens; our report exemplifies the importance of using fully matched accredited red cells for immune stimulation and the need to perform thorough antibody screening after each stimulation.

Infantile hepatic haemangioma: investigation and treatment

Infantile hepatic haemangiomas are benign tumours which tend to regress in late infancy. We describe five infants with hepatic haemangioma, three of whom developed congestive cardiac failure. Technetium-99m labelled red blood cell scan was useful in the diagnosis and follow-up of the lesion. The three symptomatic infants were treated with prednisone (2 mg/kg per day) for 2 months in addition to digoxin and diuretics. Significant clinical improvement occurred within 3 weeks in each case. We conclude that the red blood cells scan is a good non-invasive diagnostic test and recommend corticosteroids as initial management for symptomatic infantile hepatic haemangiomas.

Sequestrated meningoceles of scalp: extracranial meningeal heterotopia

Sequestrated meningocele of the scalp has seldom been reported and is difficult to diagnose. Clinically it resembles dermoid cyst, hemangioma, or alopecia; radiographs and computed tomographic scans reveal no cranial bone defect, and surgery discloses no communication with the cranial cavity. Histologically, the lesion is characterized by a loose arrangement of connective tissue in dermis and subcutis, associated with flattened cells around collagen fibers (meningothelial cells). Most examples are very vascular, sometimes mimicking angioma, and about one third contain small necrotic foci. The meningothelial nature of the lesion is shown by its architectural similarity to communicating meningocele, and its identical immunoperoxidase reactions with vimentin and epithelial membrane antigen. In the 12 cases reported herein, most lesions were small (1 to 1.5 cm), and all but one were noted at birth but usually not resected until the patient had reached age 1 to 4, and one not until the patient was 31 years of age. Five lesions were not midline. We have been unable on histologic grounds to determine whether meningoceles are communicating or sequestrated. Compared with 20 communicating meningoceles, the sequestrated lesions were usually smaller, found in slightly older patients, and much less likely to be associated with hydrocephalus. The local excision of scalp lesions in children should include a search for a small intracranial connection.

[Chronic infection due to hepatitis B virus in patients less than 16 years of age: therapeutic approach by means of interferon alfa-2b]

Twenty children with chronic Hepatitis B virus infection where treated with alfa interferon 2b and compared with a group of 24 non treated patients with similar age and sex distribution. Both treated and untreated patients, all Hepatitis B surface antigen positive for a minimum of 6 months, were divided in 2 groups according to HBeAg status: positive and negative. The treatment was ambulatory at a dose of 5.000.000 U per square meter of body surface, administered 3 times a week during 16 weeks. Tolerance of the drug was good with secondary reactions only at the beginning of the treatment. The only change in laboratory tests was the normalization of aminotransferases in HBeAg positive children. There was no significant difference between the treated and untreated group of HBeAg positive patients regarding the rate of HBeAg seroconversion. There was a striking difference in negativization of HBsAg in HBeAg negative patients: 8% in the treated group and 81% in the untreated group, this is explained by important epidemiological differences between both groups.

A simple procedure to obtain one-micrometer sections of routinely embedded paraffin material

By freezing blocks of paraffin-embedded tissues to a convenient temperature it is possible to obtain routinely 1 micron sections that can be further processed as normal thicker sections. Normal and disposable steel knives can be used and the staining time should be increased in most procedures. Gradual freezing of blocks to the temperature of dry ice is the simplest and safest way to obtain an adequate temperature. The best results were obtained using as fixative 4% paraformaldehyde in phosphate buffered saline solution.

Nasal cerebral heterotopia: the so-called nasal glioma or sequestered encephalocele and its variants

Twenty two nasal cerebral heterotopias were compared with 11 nasal encephaloceles. No histological feature was found that would allow a communication with the brain to be confidently identified or excluded. Even laminated cerebral cortex with neurones and ependymal canals, suggestive of encephalocele, were found in heterotopias. Distinction required radiological and surgical evidence. However, CT scan could be misleading, in one infant suggesting a cribriform plate defect when none was found at craniotomy. Three children had multiple extracranial glial lesions, two with both heterotopia and encephalocele in the same patient. In a few older children it was extremely difficult to identify brain tissue because of marked replacement by fibrous tissue (up to 95%), leading to one misdiagnosis as fibroma, and considerable fibrosis occurred also in five of six recurrences and in a longstanding small encephalocele. In two heterotopias, cellularity in places approached that of low-grade neoplastic glioma. One nasopharyngeal heterotopia contained multiple mesenchymal tissues suggestive of teratoma. Two midline nasopharyngeal encephaloceles showed adjacent epithelium, possibly vestiges of Rathke's pouch.

HIV surveillance by testing saliva

Saliva specimens were tested for HIV antibody (anti-HIV) by an immunoglobulin G (IgG) antibody capture radioimmunoassay (GACRIA) and three sensitive commercial assays. In tests on 460 seronegative subjects and 196 seropositive subjects GACRIA was 99.8% specific and 100% sensitive. The Wellcome HIV monoclonal and Abbott recombinant DNA enzyme-linked immunosorbent assays (ELISAs) were also highly specific (99.8%, 100%) but they were less sensitive (90.9%, 82.0%). The Fujirebio particle agglutination assay was sensitive (97.8%) but its specificity was poor (84.1%). In testing saliva specimens from populations with an anti-HIV prevalence greater than 0.5%, sampling by GACRIA alone could provide a good estimate of the true prevalence. For true prevalences less than 0.5% good estimates could only be obtained if positive GACRIA reactions were confirmed by another independent salivary assay. Salivary testing for anti HIV is a convenient and potentially an accurate epidemiological tool.