Dentist's reassuring touch: effects on children's behavior

Physical contact with patients by health care providers has been found to benefit the patients by reducing their fearful or avoidant reactions. This study tested whether a reassuring touch could be used during a routine pediatric dental examination to reduce children's anxiety and improve their behavior. Thirty-eight children between 3.5 and 10 years of age were randomly assigned to one of two experimental conditions. Children assigned to the touch condition were patted on the upper arm or shoulder on two separate occasions by the dentist during the examination while simultaneously receiving verbal reassurance and descriptions of the upcoming procedures. Children in the no-touch control condition received only the reassuring verbal descriptions without contact. Results indicated that touched children between the ages of 7 and 10 years (but not children aged 3.5 to 7 years) displayed less fidgeting behavior than their no-touch counterparts (P < 0.05). Post-treatment, children who were touched tended to report greater pleasure (P < 0.06) but less dominance (P < 0.10) than children not touched.

What makes red cells dysmorphic in glomerular haematuria?

Although red cell morphology has been used to localise the site of haematuria in the urinary tract, the cause of red cell deformity is still speculative. We have conducted experiments in vitro using venous red cells which indicate that hypochromia depends mainly upon sodium concentration and occurs when this falls below 75 mmol/l. We simulated the passage of red cells through the renal tubule by sequentially treating them with fluids of composition similar to those in different tubular segments, and produced anisocytosis and hypochromia but not the typical "bizarre deformity"--the hallmark of glomerular haematuria. We conclude that dual injury is required to produce the "typical" dysmorphic red cells in glomerular haematuria. First, mechanical damage caused by passage of red blood cells through the glomerular basement membrane followed by a second, osmotic, injury sustained by red cells during passage through the hypotonic tubular segment.

Role of intravenous immunoglobulin G in autoimmune hematologic disorders

The data presented in this review established IVIG therapy as an important treatment modality in the autoantibody-mediated cytopenias and coagulation disorders of both children and adults. The immediate response to therapy is thought to be related to nonspecific Fc-receptor blockade of mononuclear phagocytes in the reticuloendothelial system (autoimmune cytopenias), or to idiotypic antibody interaction with pathologic autoantibodies (in acquired coagulation disorders). Although less frequent, long-term responses to IVIG therapy are reported. Such responses must involve an immunomodulating effect of IgG that influences T- and B-cell function, with inhibition of pathologic autoantibody formation. It is possible that idiotypic antibody interactions play a part in long-term responses. The experience with IVIG therapy in the decade following Imbach's important observations reported in 1981 has provided a sound data base regarding the use of this important therapy in patients with autoimmune hematologic disorders. The challenge of the next decade should be to further investigate mechanisms of action of this important therapy and to conduct carefully controlled studies to answer specific clinical questions. Examples of such questions include the following: (1) Can IVIG therapy, administered early in the course of illness in selected children with acute ITP, decrease the incidence of chronic ITP?; (2) Is maintenance, high-dose IVIG therapy a cost-effective method for the management of patients with chronic ITP refractory to corticosteroid therapy and splenectomy?; and (3) Can IVIG therapy administered to selected pregnant women with ITP significantly reduce the incidence of serious thrombocytopenia in their offspring? In conducting these studies, consideration should be given to the type of IVIG preparation used and to the treatment protocol implemented. It is evident that responses to unmodified IgG preparations (with the Fc-receptor part of the molecule left largely intact) are superior to preparations that have been modified during preparation. Responses are also likely to be dose-related. The data reported for IVIG therapy in patients with acquired factor VIII deficiency suggests that the idiotypic antibody content of IgG preparations is also of importance; if so, preparations selected from specific donor pools (for example, multiparous women) known to contain higher levels of circulating autoantibodies (than those from primiparous women or untransfused males) may provide a degree of benefit not seen with standard IVIG preparations. It is therefore important that clinicians and laboratory specialists work closely together in the design and conduct of future clinical trials initiated to answer those important clinical questions raised by the first decade of observations with IVIG therapy for autoimmune hematologic disorders.

Maternal immunization with the capsular polysaccharide vaccine for Haemophilus influenzae type b

Maternal immunization with the capsular polysaccharide (PRP) vaccine of Haemophilus influenzae type b has been shown to extend the time that protective levels of maternal antibody are detected in infants. In a randomized, blinded trial, PRP or placebo was administered uneventfully to 213 women in the third trimester of pregnancy. Infants born to PRP recipients had significantly higher levels of antibody to PRP than did infants born to placebo recipients: 2.73 micrograms/ml compared with 0.33 microgram/ml. It was estimated that infants of mothers who received the PRP vaccine would be protected for an average of 4 months compared to an average of only 2 months for those of mothers who received placebo. Infants were followed for invasive H. influenzae type b disease through the first year of life; none was detected.

Effects of phosphate loading on metabolic and myocardial responses to maximal and endurance exercise

Six trained male cyclists and triathletes participated in a double blind study to determine the effects of phosphate loading on maximal and endurance exercise performance. Subjects ingested either 1 gm of tribasic sodium phosphate or a glucose placebo four times daily for 3 days prior to performing either an incremental maximal cycling test or a simulated 40-km time trial on a computerized race simulator. They continued the supplementation protocol for an additional day and then performed the remaining maximal or performance exercise test. Subjects observed a 17-day washout period between testing sessions and repeated the experiment with the alternate supplement regimen in identical fashion. Metabolic data were collected at 15-sec intervals while venous blood samples and 2D-echocardiographic data were collected during each stage of exercise during the maximal exercise test and at 8-km intervals during the 40-km time trial. Results indicate that phosphate loading attenuated anaerobic threshold, increased myocardial ejection fraction and fractional shortening, increased maximal oxidative capacity, and enhanced endurance performance in competitive cyclists and triathletes.

Covering the costs of care in neonatal intensive care units

The continued rise of health care costs, despite private and governmental control efforts, has sustained cost containment as a central issue for health care researchers and policy makers. In keeping with these concerns, the Florida Health Care Cost Containment Board conducted a study of neonatal intensive care units (NICUs) in Florida to ascertain the costs, charges, and net revenues associated with NICU services in individual hospitals, to document cost shifting and cross-subsidization as a means of financing NICU care for indigent populations, and to assess the fiscal impact of NICUs in state-sponsored vs non-state-sponsored Regional Perinatal Intensive Care Center hospitals providing NICU care. Hospitals in the state-sponsored program reported a loss of approximately $16.5 million in contrast to the non-state-sponsored hospitals, which reported a gain of $1 million. Payment being generated by private-pay patients amounted to almost 60% of total revenues but constituted less than one third of the costs in state-sponsored hospitals, indicating a high level of cost shifting. Government support of state-sponsored NICUs, while substantial, has been insufficient; increasing constraints on this funding source would likely worsen the deficit and increase the necessity of cost shifting.

Rapid anticoagulation using ancrod for heparin-induced thrombocytopenia

In order to determine the efficacy and safety of ancrod, a rapid acting defibrinogenating drug, for patients with heparin-induced thrombocytopenia, 11 consecutive patients who required anticoagulant therapy because of venous thromboembolism and who developed acute heparin-induced thrombocytopenia or had a history of heparin-induced thrombocytopenia were treated with ancrod. Heparin therapy was discontinued (in patients receiving heparin) and ancrod started at a dose of 1 to 2 U/kg every 24 hours with subsequent daily doses adjusted to maintain fibrinogen levels between 0.5 and 1.0 g/L. Ancrod was continued until warfarin had become effective. The platelet count increased to more than 150 x 10(9)/L within 2 to 10 days in all thrombocytopenic patients. Two patients with a history of heparin-induced thrombocytopenia maintained normal platelet counts while receiving ancrod. Two patients had recurrent venous thrombosis while receiving warfarin, 10 days after ancrod was discontinued: one of these patients had metastatic pancreatic carcinoma and developed phlegmasia cerulea dolens and the other patient developed a venographically proven extension of her deep venous thrombosis. One patient suffered a bleeding episode into the thigh with a 16-g/L decrease in her hemoglobin level while receiving ancrod therapy. No other side effects were noted. Our experience indicates that ancrod therapy is a reasonable approach for patients with heparin-induced thrombocytopenia who require anticoagulant therapy.

The relationship of antiphospholipid antibodies to thromboembolic disease in systemic lupus erythematosus: a cross-sectional study

In order to determine whether an association exists between antiphospholipid antibodies (APLA) and thromboembolic events in patients with systemic lupus erythematosus (SLE), we performed a cross-sectional study of consecutive unselected SLE patients. The occurrence of previous thromboembolic events was determined by investigators blinded to the APLA status of the patients by critical review of objective tests that had been performed at the time of symptomatic presentation and by performing venous Doppler ultrasound of the legs to elicit venous reflux as an indication of previous venous thrombosis. The presence of APLA was determined by coagulation assays for the lupus anticoagulant (LA) using five tests with well-defined control ranges and by ELISA assay for anticardiolipin antibodies (ACLA). These tests were measured on two separate occasions. The results of the study demonstrate a statistically significant association between persistently abnormal ACLA assays and thromboembolic events and a non-significant trend between persistently abnormal LA and thromboembolic events. Transient abnormalities of LA and ACLA were less strongly associated with thromboembolic events. We conclude that in patients with SLE, there is a significant association between thromboembolism and APLA.

Sedation and histamine H1-receptor antagonism: studies in man with the enantiomers of chlorpheniramine and dimethindene

1. The effects of 10 mg (+)- and (-)-chlorpheniramine and 5 mg (+)- and (-)-dimethindene on daytime sleep latencies, digit symbol substitution and subjective assessments of mood and well-being were studied in 6 healthy young adult humans. Each subject also took 5 mg triprolidine hydrochloride as an active control and two placebos. 2. Daytime sleep latencies were reduced with triprolidine, (+)-chlorpheniramine and (-)-dimethindene, and subjects also reported that they felt more sleepy after (+)-chlorpheniramine and (-)-dimethindene. Performance on digit symbol substitution was impaired with (+)-chlorpheniramine. 3. Changes in measures with (-)-chlorpheniramine and (+)-dimethindene were not different from changes with placebo. 4. In the present study, changes in measures of drowsiness and performance were limited to the enantiomers with high affinity for the histamine H1-receptor. These findings strongly suggest that sedation can arise from H1-receptor antagonism alone, and provide further support for the belief that the histaminergic system is concerned with the regulation of alertness in man.

Inherited bleeding disorders

Congenital bleeding disorders comprise a heterogeneous group of diseases that reflect abnormalities of blood vessels, coagulation proteins and platelets. Studies of these diseases, many of which are rare and several of which result in a mild bleeding diathesis only, have significantly increased our understanding of normal haemostasis. Two lessons have been learned. First, quantitative abnormalities of coagulation proteins and platelets are an important, but not the only, cause of significant haemorrhage; some cases of inherited bleeding disorders reflect synthesis of a dysfunctional coagulation protein or production of abnormal platelets. Diagnostic tests that reflect qualitative abnormalities are therefore important in the evaluation of selected patients with inherited bleeding disorders. Second, in occasional patients the inherited disorder is complex and reflects combined abnormalities of coagulation proteins alone or in association with platelet disorders. In clinical practice it is useful to distinguish disorders that cause significant clinical bleeding from those that cause few or no symptoms. Examples of the former include severe deficiencies of factors VIII and IX, and the homozygous forms of factor II, V, VII, X, XI, XIII, fibrinogen and von Willebrand factor. Comparable platelet disorders include the inherited thrombocytopenias with platelet counts less than 20 x 10(9) litre-1 and the homozygous forms of Bernard-Soulier syndrome and Glanzmann's thrombasthenia. The most frequently encountered mild haemostatic abnormalities include type I von Willebrand's disease, the platelet storage pool deficiency syndromes and the mild and moderate forms of haemophilia A and B; occasionally heterozygous or homozygous forms of the rarer coagulation disorders, e.g. factor XI deficiency, may present with a mild bleeding diathesis. Finally, some disorders are entirely asymptomatic, e.g. factor XII deficiency and deficiencies of other contact coagulation factors. Management of patients with inherited bleeding disorders should reflect knowledge of the specific disorder to be treated plus careful consideration of the clinical circumstance for which therapy is proposed. In all cases, once a decision to treat has been made, the safest efficacious therapy should be given (for example DDAVP in the treatment of patients with mild haemophilia A or type I von Willebrand's disease). Although blood products are now much safer and the risk of blood transmitted viral infections is low, there still remains a risk that transfusion of any blood product may be associated with serious side-effects. As a result, therapy should be given only after careful consideration of the risk: benefit ratio and not merely to treat an abnormal laboratory result.(ABSTRACT TRUNCATED AT 400 WORDS)

Different forms of chronic childhood thrombocytopenic purpura defined by antiplatelet autoantibodies

To determine whether detection of antiplatelet autoantibodies (AAb) to glycoproteins IIb/IIIa and Ib/IX may be useful in defining different forms of chronic thrombocytopenic purpura (TP) in children, we analyzed for AAb the platelet and plasma samples from 36 children with chronic TP (mean duration 4.4 years), from 31 children with normal platelet counts at the time of blood sampling but with chronic TP in the past (mean duration 2.9 years), and from 23 adults with chronic TP; the results were correlated with the clinical data. Antiplatelet autoantibodies were detected in 26 (72.2%) of 36 children with ongoing TP, 15 (48.4%) of 31 children with TP in the past, and 12 (66.7%) of 18 adults with TP. All children with high AAb ratios (greater than 5 times the control mean + 3 SD) were more than 8 years of age at diagnosis (mean age 12.4 years compared with 7.1 years in children with moderate or negative AAb levels; p = 0.003). The results suggest that the outcome for adolescents with high platelet-associated AAb levels may be similar to that of adults, whereas younger children may have a greater chance of spontaneous remission. The children with chronic TP in the past and elevated platelet-associated AAb levels may have a "compensated" TP and therefore may be at risk for relapses. Future studies aimed at serial AAb determination throughout the patients' courses may further define TP subgroups.

Evaluation of light microscopy to localise the site of haematuria

Red cell morphology was examined by light microscopy in 122 urine specimens from 99 patients with haematuria in an attempt to define the site of origin. Altogether 84% of glomerular bleeding and 91% of non-glomerular bleeding was correctly assigned according to diagnoses determined by renal biopsy in 51 patients and clinically in 48. The test should be interpreted with caution as both false positive and false negative results were observed, some in the same individual with unchanged pathology at different times. No advantage of phase contrast over bright field microscopy was apparent even when examining uncentrifuged urines.

Actin-membrane interaction in focal adhesions

Focal adhesions are regions of the plasma membrane where cells in tissue culture adhere strongly to the underlying extracellular matrix, and which at their cytoplasmic face serve to anchor bundles of actin microfilaments. They provide an experimental model for studying the links between the cytoskeleton and the extracellular matrix. Members of the integrin family of extracellular matrix receptors are prominent components, spanning the membrane in focal adhesions, but there is evidence that other membrane components are also needed for these structures to form. A number of proteins are concentrated at the cytoplasmic face of focal adhesions. Recent efforts have sought to determine the links between actin and the integrin cytoplasmic domains. Using in vitro binding assays, two potential bridges between actin and integrin have been identified. One involves talin, which has recently been shown to bind actin directly. The other involves the actin-binding protein, alpha-actinin, which has been found to interact with several integrins. The physiological significance of these two potential bridges between actin and integrin remains to be determined in vivo.

Measurement of beta 2-microglobulin, retinol-binding protein, alpha 1-microglobulin and urine protein 1 in healthy children using enzyme-linked immunosorbent assay

Enzyme-linked immunosorbent assays (ELISA) have been developed for the measurement of beta 2-microglobulin (B2M), retinol-binding protein (RBP), alpha 1-microglobulin (A1M) and urine protein 1 (UP1) in children. Results from random urine samples in 43 children (31 for B2M) are, when corrected for urine creatinine (geometric mean (range)): B2M 9.8 (6.0-40.7) micrograms/mmol, RBP 8.1 (less than 1-24.5) micrograms/mmol, A1M 0.4 (0.1-2.2) mg/mmol and UP1 17.8 (less than 2-309.4) micrograms/mmol. Fractional excretions (FE) in 23 children (14 for B2M) are (geometric mean (range)): FEB2M 0.04% (0.02-0.10%) and FEUP1 0.10% (0.01-1.21%). Results in overnight urine collections are also presented. Our results extend existing data for normal ranges in adults to include children and provide data on UP1 concentrations.

Failure of benzene and phenol to serve as substrates for the peroxidatic action of catalase

Evidence from several reports in the literature indicates a possible role for catalase in the metabolism of benzene. To investigate possible peroxidatic activity of catalase on benzene or its major metabolite, phenol, we employed an in vitro assay system that had been used previously to study the peroxidation of ethanol by catalase. Under conditions identical to those used to demonstrate catalase-mediated ethanol peroxidation we observed no peroxidase activity of catalase toward either benzene or phenol. We conclude that catalase is not involved in benzene metabolism and make the observation that, to date, no aromatic compounds have been demonstrated to be substrates for the peroxidatic mode of action of catalase.

Is alcohol a carcinogenic risk?

Consumption of alcoholic beverages has been implicated as a risk factor for the development of various cancers including oesophageal, oral, pharyngeal, laryngeal, liver and breast cancers. This article is a commentary on an earlier paper entitled 'Alcohol: a carcinogenic risk?' which challenges some of the evidence relating alcoholic beverage consumption to risk for these cancers. In the course of commenting on this paper, evidence is reviewed which shows a relationship between these cancers and consumption of alcoholic beverages, which is often found to be dose-related.

Prediction of acute renal failure after birth asphyxia

Twenty-one babies of 34-41 weeks' gestational age with birth asphyxia (5 minute Apgar score less than or equal to 5 or umbilical artery pH less than or equal to 7.2) were studied during the first two days of life to find out whether the urinary excretion of tubular markers of renal function is of value in the early diagnosis of acute renal failure. Urinary retinol binding protein, myoglobin, and N-acetyl-beta-D-glucosaminidase (NAG), expressed as a ratio with urinary creatinine, were measured and excretion profiles repeated at 3-6 days in 15 infants and at 7-14 days in 11 infants. Plasma creatinine concentration, creatinine clearance, plasma myoglobin concentration, and fractional sodium excretion were measured where possible in asphyxiated infants. Control data were obtained from 50 healthy infants: 28 gave urine samples alone, 17 urine and blood, and five blood alone. Normal urinary values were derived from 17, 25, and three infants, respectively, for the three time periods. The number of control samples was limited for ethical reasons. Four asphyxiated infants had acute renal failure (group 1), four had tubular dysfunction without glomerular disturbance (group 2) and 13 had normal renal function (group 3). Group 1 were clearly identified by greatly increased urinary retinol binding protein (greater than 27,000 micrograms/mmol creatinine) and myoglobin (greater than 1500 micrograms/mmol creatinine) excretion measured in the first two days of life. In control infants the range of excretion of retinol binding protein within the same time period was 3 to 967 micrograms/mmol creatinine and urinary myoglobin was undetectable. Excretion of NAG failed to discriminate between groups 1 and 2. Acute renal failure occurred only in infants who had heavy myoglobinaemia. Tubular dysfunction in group 2 was transient and not accompanied by plasma electrolyte disturbances. We conclude that measurement of urinary excretion of retinol binding protein or myoglobin after birth is helpful in the early diagnosis of acute renal failure.

How much alcohol is in a 'standard drink'? An analysis of 125 studies

A group of researchers have undertaken a review of 125 international, published, epidemiological studies that relate various physical harms to different levels of alcohol consumption. For this review it was necessary to be able to compare the data from the different studies directly. The different measures of alcohol quoted in the studies were converted to the standard measure of grammes of alcohol. The present paper discusses the problems involved in doing this, and gives details of the conversion methods used.

Quantitative microfocal radiography of children with renal osteodystrophy; comparison with laboratory and histological findings

High definition microfocal radiography permitted the quantitative assessment of the radiographic features of renal osteodystrophy in the phalanges of 11 children in stable chronic renal failure, treated with phosphate binders for 1 year. The most consistent feature was subperiosteal cortical resorption, expressed as a ratio total length of resorbed subperiosteal bone/total length subperiosteal bone x 100. It was found that the extent of resorbed bone was significantly greater in the middle phalanx and on the ulnar surface of the phalanges. The radiological findings over the duration of the disease were compared with laboratory assessments and bone histomorphometry. The extent of the percentage of subperiosteal resorption at base line and its change during the study period correlated significantly with the level of serum parathyroid hormone levels and its change over the same period. No other significant correlations were found between radiographic features and laboratory assessments or with bone histomorphometry.