Spatial orienting and focused attention in attention deficit hyperactivity disorder

Seventeen children with attention deficit disorder (ADHD) and 10 normal controls performed two tasks while event-related potentials were recorded. ADHD subjects took part in two more sessions under methylphenidate (MP) or placebo. In the spatial orienting task, invalidly cued targets elicited a longer reaction time (RT) and a P₃ that was longer in latency and greater in amplitude than did validly cued targets. Performance was similar for both groups, but the early portion of P₃ (300–400 ms) was lower in amplitude for invalidly cued targets in ADHD subjects. MP increased accuracy without affecting RT and shortened P₃ peak latency and increased the amplitude of its early portion. In the focused attention task, accuracy was greater for controls and MP, but there were no RT differenees. Attended stimuli elicited greater amplitude P₁, N₁, and P₃ than did nonattended stimuli, but these measures were unaffected by diagnosis or medication.     

Differential Expression of VLAβ1 (CD29) on Monocytes From Patients With Endometriosis

PROBLEM : Previous studies have established that in vitro proliferation of endometrial cells is enhanced by peripheral blood monocytes (PBM) and suppressed by peritoneal macrophages (PM) from patients with endometriosis but only suppressed by PBM and PM obtained from normal subjects. The functional activity of PBM and PM is influenced by the engagement of numerous cell surface receptors with their respective physiological ligands. METHOD : In this study, PBM and PM from fertile women (Group 1), women with unexplained infertility (Group 2), and women with limited (Group 3) or severe (Group 4) endometriosis were isolated in order to analyze these cells for the expression of CD54, CD58 and HLA-DR (immunoglobulin supergene antigens) CD18 and CD29 (integrins) and CD44 (an addresin). These cell surface antigens are involved in monocyte/macrophage trafficking, activation, signal transduction and/or adhesion. RESULTS : No differences were detected in the percentage of PBM expressing CD18, CD44, CD54, CD58, or HLA-DR among the four groups of subjects. Furthermore, the density of these antigens expressed on PBM was identical in patients and control subjects. In contrast, the percentage of PBM expressing CD29 (also known as VLAβ1) and the density of CD29 expressed per cell were significantly reduced (P < 0.01) in patients with limited endometriosis compared to controls and patients with severe disease. Interestingly, although the percentage of CD29+ PBM from women with severe endometriosis was not statistically different from the percentage of CD29+ PBM from controls, the density of CD29 expressed per cell was significantly elevated among patients with severe disease. Analysis of PM from the four subject groups revealed no differences in CD29 expression or density. However, the percentage of PM expressing CD18 was significantly decreased in patients with limited (but not severe) endometriosis. CONCLUSION : Since both CD18 and CD29 play a role in cell trafficking and/or adhesion, alterations in their expression among patients with endometriosis suggest that these integrin β chains may play a role in the pathogenesis of the disease.     

Carcinoma of the Small Intestine in Regional Enteritis

A case of carcinoma of the jejunum occurring in a patient with Crohn's disease of 30-years' duration is presented. Forty-seven previously reported small bowel carcinomas in Crohn's disease patients are reviewed. The incidence of small bowel carcinomas in patients with Crohn's disease has been cited as being as low as 0.08%, a figure which is still higher than the 1 in 10(9) population which would be predicted if the two diseases were independent of one another. The average age of incidence of the Crohn's carcinomas was 46.5 years while that for the de novo group was 55 years. The sexual ratios were 2.46:1 and 2:1, males to females, for the respective groups. The de novo carcinomas had a slight predilection for the duodenum at 40.7% while the latter group had a heavy predilection for the ileum at 70.8% and contained no duodenal carcinomas. The prognosis of the Crohn's group appeared to be much worse than that of the de novo group with five-year survivals of 3.7% and 20-22% respectively. Late diagnosis in the enteritis group was felt to be the major reason for this. Finally, several pathological differences between the lesions in both groups are presented.     

Maternal serum α-fetoprotein and low birth weight in relation to gestational age

Summary. To determine when in the first and second trimester a raised serum α-fetoprotein (AFP) level best predicts low birth weight a case-control study was performed on 157 singleton low birth-weight (2.5 kg) and 314 singleton control pregnancies (birth weight >2.5 kg). The association between raised maternal serum AFP and low birth weight was confirmed, but there was no special time in pregnancy before 29 weeks gestation when a raised AFP level predicted low birth weight materially better than at any other time.     

CLINICAL STUDIES OF INDUCTION AGENTS XXVI: THE RELATIVE POTENCIES OF THIOPENTONE, METHOHEXITONE AND PROPANIDID

A method is described for estimating the relative potenciesof intravenous anaesthetics. It is based on the time of onsetof sleep after administration of various doses of the agent.Rapid transport from the periphery is achieved by injectionat the height of a period of reactive hyperaemia. There arevarious methods of interpreting the results, but for this purposethe most reliable would seem to be the dose producing anaesthesia,as shown by the inability of the patient to count, in 90 percent of patients within 11 seconds of the end of the injection.Studies of thiopentone, methohexitone and propanidid were carriedout and gave the potency ratio for methohexitone to thiopentoneas 3.3 to 1 and for thiopentone to propanidid as 1.1 to 1.     

Iron Metabolism in Porphyria Cutanea Tarda and in Erythropoietic Protoporphyria

Absorption of radioiron, plasma iron and iron-binding capacity,plasma iron turnover and utilization of radioiron, tissue ironstores, and hepatic biopsy histology have been studied in 20patients with porphyria cutanea tarda (PCT). Some of these facetsof iron metabolism were also studied in five patients with erythropoieticprotoporphyria (EPP). Iron absorption was increased in nine untreated patients withPCT, particularly in those with cirrhosis, and was inappropriatelygreat in a further three. It was markedly increased in six patientswith PCT in remission many months after treatment by repeatedphlebotomy. Iron absorption was normal in two patients withEPP and raised in another in whom marrow storage iron was absent. Plasma iron was elevated in 15 of the patients with PCT, butin eight it fell into the normal range after their admissionto hospital, probably in part as a result of their stoppingtaking alcohol. Total iron-binding capacity was usually normal.Plasma iron turnover was mildly increased in seven of 20 patientswith PCT, and was normal in three with EPP. Utilization of radioironwas slightly reduced in two patients with PCT, and normal in14 others with PCT and in two with EPP. Liver biopsy in 18 untreatedpatients with PCT invariably showed evidence of liver damage,with excess iron in parenchymal cells, Kupffer cells, and, withone exception, portal tract macrophages. Repeat biopsy in fourpatients with PCT in remission after repeated phlebotomy showedabsence of stainable iron in three with normal liver architecture,and a marked reduction in excess iron in one with cirrhosis.Reticulo-endothelial iron was increased in marrow smears fromsix of 14 patients with PCT, and was absent in one and minimalin two patients with EPP. Storage iron mobilized by repeatedphlebotomy amounted to from 0.4 to 1.8 g in 12 patients withPCT. One patient with EPP had recurrent iron-deficiency anaemiaand in three others mobilizable storage iron was less than 250mg. The observations confirm the invariable finding of excess hepaticiron in PCT, with often a modest increase in mobilizable storageiron. The increase appears to be due to an inappropriately highlevel of iron absorption of uncertain cause. In contrast, suboptimalstorage iron may be frequent in EPP.