Stroke in the young. Part II

Evaluation of the young stroke patient often requires an interdisciplinary approach because of the complexity of the problems encountered. We discuss some of the less common causes of stroke and present an approach to the patient.

Platelet aggregation in hyperapobetalipoproteinemia

Hyperapobetalipoproteinemia (HyperapoB) is a lipid disorder characterized by premature coronary disease, although the mechanisms have not been elucidated. Because abnormalities in platelet function may represent an enhanced susceptibility to coronary thrombosis, the aggregability of platelets was examined in hyperapoB subjects. Compared to controls, there were no significant differences in either platelet lipid composition or in aggregation to epinephrine, ADP, or collagen. In contrast to other dyslipidemias, platelet function does not appear to be abnormal in this well defined lipid disorder.

Stroke in the young. (Part I)

We have discussed some of the more common etiologic categories found in young patients with stroke. Though many of the causes are rare, in the aggregate they account for many of the conditions leading to stroke. In Part II of this series (July 1991), we will explore some of the less common causes of stroke in the young and outline an approach to the patient.

The effect of back closure on detrusor function in neonates with myelomeningocele

To determine the effect of back closure on the detrusor-external sphincter coordination, we reviewed the medical records of 40 neonates with myelodysplasia studied prospectively with urodynamic assessment and renal ultrasonography before closure of the spinal defect, within 7 days of closure and at 3-month intervals thereafter. Only 31 of the 40 neonates met all criteria for inclusion. All renal sonograms were normal before and after closure. Urodynamic evaluation demonstrated coordinated detrusor-sphincter activity in 18 neonates before and after closure. During prolonged followup 1 patient had detrusor areflexia and 4 had detrusor-sphincter dyssynergia. Of 11 neonates who demonstrated detrusor areflexia and no external sphincter activity before closure 10 were unchanged on initial post-closure evaluation (4 had detrusor-sphincter dyssynergia during followup), while 1 demonstrated detrusor areflexia with external sphincter overactivity and vesicoureteral reflux after closure. The latter patient subsequently had detrusor hyperreflexia, more severe reflux and upper tract deterioration. She was temporized with a cutaneous vesicostomy. One patient demonstrated detrusor-sphincter dyssynergia before closure and detrusor areflexia with no external sphincter activity after closure, the consequence of surgical division of the neural placode during back closure. The remaining patient demonstrated detrusor-sphincter dyssynergia before and after closure. This patient had coordinated detrusor-sphincter activity during followup. Those neonates who presented with or later had detrusor-sphincter dyssynergia were managed initially with neuropharmacological agents and clean intermittent catheterization. An unsuccessful outcome was managed by cutaneous vesicostomy. Our study demonstrates that neonatal closure of the spinal cord defect does not appear to affect detrusor-sphincter coordination adversely, and re-emphasizes the need for careful and regular followup in children with myelodysplasia to detect deterioration of the urinary tract.

Specific identification of fibrin(ogen) degradation products in plasma and serum using blotting and peroxidase labeled antiserum

We describe a method for identifying fibrinogen and fibrin split products using electrophoresis on agarose gel with sodium dodecyl sulfate (SDS) followed by blotting in nitrocellulose paper. Detection of these derivatives after blotting is accomplished with peroxidase-conjugated rather than by isotopically labeled antibodies. This technique can detect diverse fibrinogen derivatives produced in vivo or in vitro by the combined action of thrombin, plasmin, and factor XIII. This methodology is applicable to plasma, serum, and other body fluids including urine and ascitic fluid. This sensitive and specific assay, distinguishing the products of cross-linked fibrin from those of fibrinogen and detecting fibrin polymers in plasma, can be achieved without the use of radioactivity.

Effectiveness of a method used in bonding resins to metal

Currently, several methods are available for bonding resin veneers to dental casting alloys. Recently a new system (Silicoater) has been developed that involves the chemical bonding of polymers to dental substrates. This study determined bond strengths of several proprietary composite resin luting agents to three different types of casting alloys. The results were compared with those obtained using electrolytic etching techniques. The pyrogenically silica-treated specimens generated the highest bond strengths.

Effects of 1 alpha, 25-dihydroxyvitamin D3 on the human chronic myelogenous leukemia cell line RWLeu-4

The effects of 1 alpha, 25-dihydroxyvitamin D3 (VD3) on proliferation, differentiation, and macromolecular synthesis in the new Philadelphia chromosome-positive chronic myelogenous leukemia cell line, RWLeu-4, were investigated. Binding of [3H]VD3 was saturable, with approximately 2000-3000 sites/cell, and half-maximal binding occurring at 0.21-0.33 nM. Treatment of RWLeu-4 cells with VD3 induced 24R-hydroxylase activity, a marker of vitamin D3 responsiveness in many tissues. Exposure of RWLeu-4 cells to VD3 also inhibited proliferation and DNA synthesis with a 50% effective dose of 3.5-10 nM within 72 h; in addition, protein and RNA synthesis were inhibited by VD3 treatment. Exposure of RWLeu-4 cells to 5 nM VD3 for 72 h caused 50% of the cells to differentiate into macrophage/monocyte type cells as judged by nitroblue tetrazolium staining and adherence to plastic. Progressive expression of cell surface maturation-specific antigens of the monocyte/macrophage lineage was induced by treatment of RWLeu-4 cells with VD3 for 24 to 72 h at doses that inhibited cellular proliferation. c-myc RNA, which is constitutively expressed in RWLeu-4 cells, increased after 0.5 h of treatment with 50 nM VD3 and then rapidly decreased to barely detectable levels after 4 h of treatment. Finally, the in vitro tyrosine kinase activity associated with the p210bcr-abl oncogene product was decreased approximately 50% by VD3 treatment. Because of the presence of a functional receptor-effector system for VD3 and multiple biological responses to the hormone, these cells provide a unique model system with which to probe the specific effects of VD3 on cell growth and differentiation in chronic myelogenous leukemia.

Ethnicity: post-traumatic stress disorder (PTSD) differences among black, white, and Hispanic veterans who differ in degrees of exposure to combat in Vietnam

Clinical observations and empirical evidence suggest that, among Vietnam combat veterans, Blacks are more maladjusted than Whites (e.g., Parsons, 1985; Penk et al., 1985). The prediction that minority group status is associated with poorer post-war adjustment and higher rates of PTSD was examined among Vietnam combat veterans who were seeking treatment for addiction disorders. Adjustment scores among groups comparable in combat exposure were found to be similar for both Whites and Hispanics; Blacks, however, score significantly higher on both PTSD symptoms on MMPI scales. These findings indicate that ethnicity contributes importantly to PTSD in selected instances, but that minority group status alone does not account for observed differences. Additional research is indicated in which careful attention is given to the complicating and interacting role of addiction disorders in sampling.

Effect of reduced training volume on cardiac function, VO2 max, and running performance

This study examined the physiological effects of reducing training mileage in a veteran long distance runner while increasing exercise intensity. Variables measured included stroke volume, cardiac output, maximum oxygen uptake, ventilation threshold and performance time in a 10,000 m run. For 8 weeks, training mileage was reduced from 75.8 miles per week to 42.5 miles per week including interval training twice weekly. Following the specialized training, performance time was 10 seconds faster although VO2max and heart contractility had decreased. It was concluded that distance running performance can be maintained while considerably reducing training mileage and increasing exercise intensity twice a week.

Co-morbidity: lessons learned about post-traumatic stress disorder (PTSD) from developing PTSD scales for the MMPI

Results from efforts to develop and validate PTSD measures are promising, but a "gold standard" has not been achieved. Keane, Malloy, and Fairbank (1984) have developed an MMPI PTSD subscale that has been cross-validated with clinicians' classification of PTSD at acceptable levels of agreement, specificity, and sensitivity. There is, however, room for improvement. Empirical evidence is presented that indicates that the next round of efforts to increase reliability and validity of PTSD measures must account for the presence/absence of co-morbidity (i.e., the simultaneous occurrence of other psychiatric disorders). For example, differences are noted in MMPI group profiles and PTSD scales between psychiatric patients and substance abusers. Second, different MMPI items emerge as indicative of PTSD; these vary as a function of the presence of other Axis I disorders among groups of Vietnam combat veterans who seek treatment for substance abuse. Results substantiate that different MMPI items for classifying PTSD occur with groups that differ in co-morbidity. Improvements in PTSD scale development are more likely when the contributions of pre-existing or subsequently co-occurring psychiatric disorders are taken in account, as well as variations in level of personality maturity. The evidence suggests that a "family" of PTSD scales need to be developed that take into account co-morbidity differences.

Depletion of white cells from platelet concentrates with a new adsorption filter

Removal of white cells (WBCs) from platelets may reduce alloimmunization to WBC antigens, prevent febrile reactions, and improve platelet increments in multiply transfused patients receiving HLA-matched platelets. A new surface-modified fibrous polyester filter was evaluated; it requires no special processing of pooled platelet concentrates and can be used at the patient's bedside. The studies were designed to measure WBC removal, platelet function, in vitro platelet recovery, and in vivo platelet survival. WBC mean removal was 99.8 percent +/- 0.56 (n = 37) when a pool similar in volume to 6 platelet concentrates was tested. The mean number of residual WBCs after filtration was 5.6 x 10(5). In vitro mean platelet recovery was 86.9 percent for a pool size of 6 units (n = 37). Clot retraction and platelet aggregation were unaffected by filtration. Survival studies of 111Indium-labeled platelets done with filtered autologous platelets showed no reduction in the normally expected survival. These studies indicated that the filter efficiently removes WBCs without substantially decreasing platelet number, survival, or function. This device offers the potential of considerably improving platelet transfusion therapy.

Nonsense and missense mutations in hemophilia A: estimate of the relative mutation rate at CG dinucleotides

Hemophilia A is an X-linked disease of coagulation caused by deficiency of factor VIII. Using cloned cDNA and synthetic oligonucleotide probes, we have now screened 240 patients and found CG-to-TG transitions in an exon in nine. We have previously reported four of these patients; and here we report the remaining five, all of whom were severely affected. In one patient a TaqI site was lost in exon 23, and in the other four it was lost in exon 24. The novel exon 23 mutation is a CG-to-TG substitution at the codon for amino acid residue 2166, producing a nonsense codon in place of the normal codon for arginine. Similarly, the exon 24 mutations are also generated by CG-to-TG transitions, either on the sense strand producing nonsense mutations or on the antisense strand producing missense mutations (Arg to Gln) at position 2228. The novel missense mutations are the first such mutations observed in association with severe hemophilia A. These results provide further evidence that recurrent mutations are not uncommon in hemophilia A, and they also allow us to estimate that the extent of hypermutability of CG dinucleotides is 10-20 times greater than the average mutation rate for hemophilia A.

Characterization of antibody and selection of alternative drug therapy in hydrochlorothiazide-induced immune hemolytic anemia

The authors report the clinical and laboratory findings of a patient who had severe immune hemolytic anemia due to hydrochlorothiazide (HCTZ). In this case, the HCTZ antibody reacted not only with other thiazide and thiazide-like drugs, but also with a chemically unrelated diuretic, ethacrynic acid. These results indicate that HCTZ antibody activity is not restricted solely to the thiazides and imply that therapy with any of the reactive drugs would be contraindicated for this patient. The serologic screening for drug reactivity may be useful for selecting alternative therapy for patients with drug-induced immune hemolytic anemia.

Coping and defending styles among Vietnam combat veterans seeking treatment for posttraumatic stress disorder and substance use disorder

A review of the literature on coping processes in addiction disorders yields at least two notions: one, that substance abuse is associated with less efficient, avoidant ways of coping with problems in living; and two, that substance abusers with a background of traumatic and stressful experiences are readily distinguishable by even more avoidant coping styles. These notions were tested in the form of three hypotheses: (1) substance abusers in general employ more avoidant coping styles than do nonaddicted groups; (2) Vietnam combat veterans meeting DSM-III criteria for both substance use disorder and posttraumatic stress disorder (PTSD) evidence significantly more avoidant coping styles than do Vietnam combat veterans meeting criteria only for substance use disorder but not PTSD--particularly when dealing with internal states of anxiety; and (3) for those meeting both substance use disorder and PTSD criteria, black Vietnam combat veterans (who presumably have encountered more stress, as minority group members) evidence more avoidant coping styles than do white Vietnam combat veterans. These three hypotheses were tested with Peck's (1981) newly developed Individual Styles of Coping, measuring four stages in the coping process for five behavioral contexts. All three hypotheses were confirmed. Results were discussed as confirming recent changes in DSM-III-Revised (1987) criteria, emphasizing generalized avoidance manuevers as criterial, in part, for diagnosing PTSD (in addition to behaviors of specific avoidance of traumatic memories). Theoretical implications about a traumatogenic dimension for substance abuse among some Vietnam combat veterans were discussed, as well as ramifications for treatment programming.

Objectives of thrombolytic therapy in acute myocardial infarction

The objectives of thrombolytic therapy in acute myocardial infarction are to restore coronary artery patency, salvage myocardium, reduce infarct size, and facilitate coronary artery repair. Urokinase and streptokinase are the two most frequently used thrombolytic agents. Both dissolve thrombi by converting circulating plasminogen, an inert precursor, into plasmin. One possible advantage of urokinase and streptokinase over new clot-specific agents is that the former have systemic fibrinolytic effects. This reduces blood viscosity and prevents other thrombi from forming. Angiography is the most objective technique for assessing reestablished arterial patency, but being invasive, it present disadvantages. Noninvasive criteria for coronary reperfusion include lowering of elevated ST-segments, shifting creatine kinase isoenzyme MB curves, and the appearance of reperfusion arrhythmias. Techniques for assessing myocardial salvage include thallium uptake, assessment of wall motion and myocardial thickening, ejection fraction, and positron emission tomography to assess infarct size. The role and appropriate timing of coronary artery repair after thrombolytic therapy are being studied.

Massive gastrointestinal hemorrhage in children with posterior fossa tumors

Over a 12-month period (September 1984 to September 1985), 64 children with newly diagnosed brain tumors were admitted to the Neurosurgical Service at The Children's Hospital of Philadelphia. Of these children, 29 had posterior fossa tumors. Of this population of children with posterior fossa tumors, three patients aged 4 months, 22 months, and 4 years old developed massive exsanguinating upper gastrointestinal hemorrhage within seven days of their primary neurosurgical procedure. In each instance, large posterior duodenal ulcers were encountered and were treated with oversewing of the duodenal ulcer and vagotomy-pyloroplasty. Follow-up currently ranges from 18 to 26 months. All three children have survived and none have had any gastrointestinal bleeding since then. Massive exsanguinating hemorrhage was not seen in children with brain tumors in locations other than the posterior fossa. In this population of patients, we advocate the use of prophylactic cimetidine and titration of gastric acidity with antacids.

Fatal immune hemolytic anemia and hepatic failure associated with a warm-reacting IgM autoantibody

Autoimmune hemolytic anemia (AIHA) caused by warm-reacting IgM autoantibodies is rare. We report a fatal case of primary AIHA with a warm-reacting IgM autoantibody. Recurrent episodes of intravascular hemolysis, unresponsive to all therapy and progressive hepatic dysfunction characterized the patient's clinical course. Despite corticosteroid therapy, splenectomy and multiple blood transfusions, the patient died from liver failure. The IgM autoantibody caused autoagglutination of the patient's red cells at 37 degrees C. Eluates prepared from the patient's red cells agglutinated saline-suspended test cells without the addition of antiglobulin reagent. We propose that warm-reacting IgM antibodies may lead to in vivo autoagglutination and may be associated with hepatic failure.

Estimation of transfused red cell survival using an enzyme-linked antiglobulin test

An enzyme-linked antiglobulin test (ELAT) method was developed to estimate survival of transfused red cells. This procedure is based on a principle analogous to that of the Ashby technique were antigenically distinct red cells are transfused and their survival studied. We compared the ELAT survival to the 51Chromium method (51Cr) in four patients. Three patients with hypoproliferative anemias showed T 1/2 by ELAT of 17.5, 18, and 17 days versus 18.5, 20, and 19 days by the 51Cr method. A fourth patient with traumatic cardiac hemolysis had two studies performed. In this case, the ELAT showed a T 1/2 of 10 and 8.1 days while 51Cr T 1/2 values were 11 and 10.5 days. The ELAT method for measuring red cell survival yielded data which agreed closely with the results of the 51Cr method. Although 51Cr is the accepted method for red cell survival, the ELAT method can be used to estimate transfused red cell survival.

Late repair of the calcaneal tendon with carbon fibre

Ruptures of the calcaneal tendon which present late may be repaired using carbon fibre to induce a neotendon. The operative technique is described and the results of five cases reviewed. The average muscle power obtained was 88% of normal, and the thickness of the neotendon was 148% of that of the normal side. It would appear that this tendon formation in man is comparable to that previously described in sheep.