Preoperative preparation programs in children: a comparative examination

We sought to determine whether an extensive behavioral preparation program for children undergoing surgery is more effective than a limited behavioral program. The primary end point was child and parent anxiety during the preoperative period. Secondary end points included behavior of the child during the induction of anesthesia and the postoperative recovery period. Several days before surgery, children (n = 75) aged 2-12 yr randomly received either an information-based program (OR tour), an information + modeling-based program (OR tour + videotape), or an information + modeling + coping-based program (OR tour + videotape + child-life preparation). Using behavioral and physiological measures of anxiety, we found that children who received the extensive program exhibited less anxiety immediately after the intervention, in the holding area on the day of surgery, and on separation to the operating room. These findings, however, achieved statistical significance only in the holding area on the day of surgery (44[10-72] vs 32[8-50] vs 9[6-33]; P = 0.02). Similarly, parents in the extensive program were significantly less anxious on the day of surgery in the preoperative holding area, as assessed by behavioral (P = 0.015) and physiological measures (P = 0.01). In contrast, no differences were found among the groups during the induction of anesthesia, recovery room period, or 2 wk postoperatively. We conclude that children and parents who received the extensive preoperative preparation program exhibited lower levels of anxiety during the preoperative period, but not during the intraoperative or postoperative periods. IMPLICATIONS: The extensive behavioral preoperative program that we undertook had limited anxiolytic effects. These effects were localized to the preoperative period and did not extended to the induction of anesthesia or the postoperative recovery period.     

Molecular characterisation of a distinct South African cassava infecting geminivirus

African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV) are whitefly-transmitted geminiviruses (WTGs) which are widespread in cassava in Africa and cause serious yield losses. Recently, a new geminivirus affecting cassava in South Africa (SACMV) has been reported. In this work SACMV was found to have DNA-A and DNA-B components. Comparisons of amino acid sequences of the putative coat protein, and nucleotide sequences of the common region and a 687-bp DNA B fragment of SACMV with other WTGs, showed that SACMV clustered with the Old World subgroup of the Begomovirus genus of geminiviruses. Despite its bipartite nature, SACMV was most closely related to monopartite TYLCVs, but was sufficiently different to justify designating it as a distinct virus. In serological studies, SACMV grouped biologically with EACMV isolates.     

Molecular mapping with functional antibodies localizes critical sites on the human IL receptor common gamma (gamma c) chain

The IL receptor common gamma (gamma c) chain is required for the formation of high affinity cytokine receptor complexes for IL-2, IL-4, IL-7, IL-9, and IL-15, and for signals regulating cell survival, growth, and differentiation. Our current understanding of how gamma c chain associates with multiple ligands and receptor subunits is drawn largely from its structural homology to the human growth hormone (hGH) receptor and known structure of the hGH/hGH receptor complex. These receptors share distinct features in their extracellular portions and are believed to function by a mechanism of ligand-induced association of receptor subunits. Here, we report the first directed mutational analysis of the human gamma c chain by alanine scanning conducted across seven regions likely to contain residues required for intermolecular contact. Functionally distinct, neutralizing anti-gamma c mAbs were employed to define critical residues. One particular mAb, CP.B8, unique in its ability to inhibit IL-2-, IL-4-, IL-7-, and IL-15-induced proliferation and high affinity cytokine binding of normal T cells as an intact mAb and as a Fab fragment, localized critical residues to four noncontinuous stretches, namely residues in loops AB and EF of domain 1, in the interdomain segment, and in loop FG of domain 2. Notably, these residues form a contiguous patch on the gamma c chain surface in a three-dimensional structural model. These results provide functional evidence for the location of contact points on gamma c chain required for its association with multiple ligands.     

Tolerant B lymphocytes acquire resistance to Fas-mediated apoptosis after treatment with interleukin 4 but not after treatment with specific antigen unless a surface immunoglobulin threshold is exceeded

Susceptibility to Fas-mediated apoptosis in nontolerant B cells is regulated in a receptor-specific fashion. To explore the regulation of Fas killing in tolerant, autoreactive B cells, mice doubly transgenic for hen egg lysozyme (HEL)-specific B cell receptors and soluble HEL were examined. Engagement of CD40 led to enhanced Fas expression and acquisition of sensitivity to Fas-mediated apoptosis in tolerant B cells, similar to that observed in nontolerant, receptor transgenic B cells. Engagement of surface immunoglobulin by specific (HEL) antigen failed to induce Fas resistance in tolerant B cells, in contrast to its effect on nontolerant B cells; however, cross-linking of biotinylated HEL with streptavidin induced similar levels of Fas resistance in tolerant and nontolerant B cells, which approximated the degree of Fas resistance produced by anti-Ig. Unlike surface Ig (sIg) engagement, physiological engagement of IL-4 receptors produced similar levels of Fas resistance in tolerant and nontolerant B cells. Thus, tolerant B cells differ from nontolerant B cells in the diminished capacity of surface immunoglobulin engagement to produce Fas resistance; however, tolerant B cells can be induced to become resistant to Fas-mediated apoptosis by IL-4 or by higher order cross-linking of sIg receptors.     

Hydatid cyst of the interventricular septum in a 3.5-year-old child

An asymptomatic cardiac cyst located in the interventricular septum was diagnosed in a 3.5-year-old child by echocardiographic findings. Surgical ablation was done and histopathologic analysis confirmed a hydatid cyst. The patient was discharged without symptoms.     

Activation of extracellular matrix metalloproteinases in equine laminitis

Samples of connective tissue obtained from the hoof of six laminitic and eight non-laminitic adult horses were analysed zymographically to investigate whether connective tissue matrix metalloproteinases are activated or induced during laminitis. The activity or matrix metalloproteinases was substantially greater in the tissues from the laminitic horses than in the tissues from the non-laminitic horses. A comparison of the collagenolytic activity in the laminitic and control tissues showed that collagenolytic activities corresponding to the 92 kDa (P < 0.001), 72 kDa (P < 0.01) and 66 kDa (P < 0.01) bands were induced in the laminitic tissues.     

Molecular analysis of the PDS gene in Pendred syndrome

Pendred syndrome is an autosomal recessive disorder characterized by the association between sensorineural hearing loss and thyroid swelling or goitre and is likely to be the most common form of syndromic deafness. Within the thyroid gland of affected individuals, iodide is incompletely organified with variable effects upon thyroid hormone biosynthesis, whilst the molecular basis of the hearing loss is unknown. The PDS gene has been identified by positional cloning of chromosome 7q31, within the Pendred syndrome critical linkage interval and encodes for a putative ion transporter called pendrin. We have investigated a cohort of 56 kindreds, all with features suggestive of a diagnosis of Pendred syndrome. Molecular analysis of the PDS gene identified 47 of the 60 (78%) mutant alleles in 31 families (includes three homozygous consanguineous kindreds and one extended family segregating three mutant alleles). Moreover, four recurrent mutations accounted for 35 (74%) of PDS disease chromosomes detected and haplotype analysis would favour common founders rather than mutational hotspots within the PDS gene. Whilst these findings demonstrate molecular heterogeneity for PDS mutations associated with Pendred syndrome, this study would support the use of molecular analysis of the PDS gene in the assessment of families with congenital hearing loss.     

Effect of dose, schedule, and route of administration on the in vivo toxicity and antitumor activity of two activated sulfhydryl derivatives of cyclophosphamide

Two cyclophosphamide (CP) derivatives, 4-S-(hexane-6-ol)-sulfidocyclophosphamide (C-1) and 4-S-(propionic acid)-sulfidocyclophosphamide (C-2), that hydrolyze spontaneously under physiological conditions to 4-hydroxycyclophosphamide, are compared to CP for antitumor activity in male C57BL/6 x DBA/2 F1 mice with ascites L1210 leukemia or solid Lewis lung carcinoma. When C-1 or C-2 is administered i.p. as a single injection at 10% lethal dose (approximately LD10) to mice bearing L1210 (1 x 10(5) cells i.p.), early treatment produces a 5- to 6-log tumor cell kill and results in substantial numbers of long-term survivors (greater than or equal to 30 days). Such antitumor activity is comparable to that of CP treatment. However, i.p. administration of either sulfido derivative produces liver atrophy and fibrosis of hepatic capsular structures. Hepatotoxicity is eliminated if single-dose C-2 (less than or equal to LD10) is administered i.v.; however, when administered by this route, C-2 results in only a 1-log cell kill of i.v. implanted leukemic cells as compared to the 4-log tumor cell kill obtained with CP given i.v. In addition to hepatotoxicity, C-2 causes an acute and dose-limiting toxicity in mice, manifested by severe muscular spasms and cessation of breathing. In the treatment of advanced L1210, C-2 shows no therapeutic advantage over CP. When mice bearing s.c. Lewis lung carcinoma receive early i.p. treatment with CP, C-1, or C-2, each drug results in long-term tumor-free survivors. However, CP (< LD10) consistently cures all mice, whereas C-1 or C-2 (approximately LD10) produces only 10 to 30% tumor-free survivors. These data suggest that, in the L1210 and Lewis lung tumor systems studied, the two activated CP derivatives offer no therapeutic advantage over CP. In addition, two forms of toxicity occur with these derivatives that do not occur with CP.     

Variations in the relationship of the major vessels of the left coronary groove in the dog

The anatomic relationship of the 2 major vessels of the left coronary groove was studied in 140 dogs. Five basic patterns of disposition were observed: 1) circumflex artery superficial from its origin to the caudodorsal cardiac margin, coronary vein deep and not visible (22%); 2) coronary vein superficial from the ventral interventricular septum to the caudodorsal cardiac margin, circumflex artery deep and not visible (15%); 3) circumflex artery and coronary vein both superficial and running parallel with each other along the groove (8%); 4) coronary vein crossing circumflex artery at some point along the groove (44%); and 5) circumflex artery crossing coronary vein at some point along the groove (11%). These variations were found to influence certain experimental modifications of the left circumflex blood flow in the dog.     

Reliability of the Part II board certification examination in psychiatry: examination stability

OBJECTIVE: The aim of this study was to examine the reliability (examination stability) of the American Board of Psychiatry and Neurology (ABPN) Part II (oral) examination in psychiatry. METHOD: The authors analyzed the consistency (agreement between grades given by two independent examiners) for a 1-year examination cycle using a weighted kappa statistic and compared different parts of the examination (live patient and videotape), different examination sites, different days, and different times of the day. RESULTS: There was no significant difference in agreement between examiners by different parts of the examination, examination site, day of the week, or time of day. CONCLUSIONS: The stability of the Part II ABPN examination in psychiatry is not influenced significantly by the format or site of administration. Candidate performance is the predominant factor in the determination of passing or failing grades.