Chronic myeloid leukemia kinase domain mutations: A retrospective descriptive study on the therapeutic and prognostic significance in patients at King Edward VIII Hospital, KwaZulu-Natal, South Africa

Background

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm that harbors the Philadelphia chromosome. Tyrosine kinase inhibitor (TKI) therapy has dramatically improved the survival of patients with CML. Nevertheless, 20%-40% of CML patients require changes in TKI therapy due to intolerance or drug resistance. A total of 30%-60% of resistant cases result from kinase domain (KD) mutations. There is currently no published data on CML KD mutations in South Africa.

Methods

This retrospective, descriptive study collected data from 206 CML patients attending the King Edward Hospital Hematology clinic. Patient-based and mutation-based factors were analyzed using descriptive statistical analysis and Kaplan-Meier curves for survival analysis.

Results

KD mutations were detected in 29.1% (n = 60 of 206). A total of 40 different KD mutations were detected, with unknown responses to TKI therapy in 65% (n = 26 of 40). A total of 57.7% (n = 15 of 26) of mutations with an unknown response, showed a response to specific TKIs in our study. Four patients had A399T mutations, of which two showed good responses to Nilotinib. Patients with I293N and V280M mutations showed good responses to Imatinib. G250E was most frequently detected. Despite M351T being one of six most commonly reported KD mutations globally, this mutation was not detected in our patient cohort. A total of 20.9% (n = 43 of 206) human immunodeficiency virus (HIV) positive patients were identified, of which 25.6% (n = 11 of 43) had KD mutations. HIV status showed no significant effect on mutational status or overall survival.

Conclusion

The predicted response to TKI therapy was unknown in more than half of the KD mutations detected in our patient population. Additionally, eight patients with mutations with known responses to TKIs showed responses discordant to that expected. HIV status and KD mutations had no statistically significant effect on overall survival. Although some data were comparable to international publications, few notable differences warrant further investigation.

Response and remediation actions following the detection of Naegleria fowleri in two treated drinking water distribution systems, Louisiana, 2013-2014

Naegleria fowleri causes the usually fatal disease primary amebic meningoencephalitis (PAM), typically in people who have been swimming in warm, untreated freshwater. Recently, some cases in the United States were associated with exposure to treated drinking water. In 2013, a case of PAM was reported for the first time in association with the exposure to water from a US treated drinking water system colonized with culturable N. fowleri. This system and another were found to have multiple areas with undetectable disinfectant residual levels. In response, the water distribution systems were temporarily converted from chloramine disinfection to chlorine to inactivate N. fowleri and reduced biofilm in the distribution systems. Once >1.0 mg/L free chlorine residual was attained in all systems for 60 days, water testing was performed; N. fowleri was not detected in water samples after the chlorine conversion. This investigation highlights the importance of maintaining adequate residual disinfectant levels in drinking water distribution systems. Water distribution system managers should be knowledgeable about the ecology of their systems, understand potential water quality changes when water temperatures increase, and work to eliminate areas in which biofilm growth may be problematic and affect water quality.

Identifying Gaps in Metastatic Breast Cancer Patient Knowledge and Their Communication Experiences With Health Care Professionals and Developing Visually Based Solutions to Overcome Those Gaps

Background: Metastatic breast cancer (MBC) is the fifth most common cause of death from cancer globally.1 MBC is incurable and its trajectory complicated. Patients have only a few days to choose treatments after an unexpected diagnosis, and most conversations with health care professionals (HCPs) are oral, a communication method with low retention accuracy (14%).2 Patients and caregivers feel ill prepared and overwhelmed. Yet when visuals are introduced into HCP/patient communication, accurate recall can be as high as 85% for low-literacy populations.2 Aim: Test if visually based communication tools can be used by HCPs to increase MBC patient and caregiver understanding of MBC as incurable, and confidence in making treatment decisions for quality of life. Methods: Survey of MBC patients (n=487) communication experience prior to treatment of Stage IV; interviews with HCPs (n=20) in the clinic to identify communication barriers with patients; empathy role play with HCPs and patients to clarify viewpoints (n=7); analysis of patient materials; in-depth interviews with MBC patients and communication experts (n=12); iterative design process of communication tool prototype with MBC patient group (n=48) and HCPs. Results: Only 1 in 8 patients were educated with visuals during initial discussions with HCPs. Less than half of patients (46%) included HER2 and hormone receptor status when asked to describe their subtype. One-third of patients felt they did not have enough knowledge to participate in decision-making for treatment and 58% of patients felt rushed to start; 71% did not recall discussing goals/hobbies; and just 62% discussed pain and symptom management. HCPs want to deliver difficult news in a clear and empathetic way, reduce repetition, save time educating patients, and have better tools for caregivers; current patient materials are impersonal and overwhelming. Iterative development and testing of the MBC Communication Toolkit prototype with HCPs and patients showed patients understood treatment options more easily with a visual metaphor while HCPs using the prototype said the images were effective for communicating symptoms and treatment options. Conclusion: A visual approach to improving communication between MBC patients and caregivers and their HCPs seems possible based on positive results of patient interpretation and practitioner feedback. Visual tools can help HCPs engage patients with information to enable them to understand their disease, goals, and nature of treatments so they can make informed, appropriate decisions. REFERENCES 1. International Agency for Research on Cancer: Breast cancer: estimated incidence, mortality and prevalence worldwide in 2012. Available at https://globocan.iarc.fr/Pages/fact-sheets_cancer.aspx 2. Houts PS, Witmer JT, Egeth HE, et al: Using pictographs to enhance recall of spoken medical instructions II. Patient Educ Couns 43:231-242, 2001 https://doi.org/10.1016/S0738-3991(00)00171-3

Hydraulically amplified self-healing electrostatic actuators with muscle-like performance

Existing soft actuators have persistent challenges that restrain the potential of soft robotics, highlighting a need for soft transducers that are powerful, high-speed, efficient, and robust. We describe a class of soft actuators, termed hydraulically amplified self-healing electrostatic (HASEL) actuators, which harness a mechanism that couples electrostatic and hydraulic forces to achieve a variety of actuation modes. We introduce prototypical designs of HASEL actuators and demonstrate their robust, muscle-like performance as well as their ability to repeatedly self-heal after dielectric breakdown-all using widely available materials and common fabrication techniques. A soft gripper handling delicate objects and a self-sensing artificial muscle powering a robotic arm illustrate the wide potential of HASEL actuators for next-generation soft robotic devices.

Synovial Fluid Profile at the Time of Anterior Cruciate Ligament Reconstruction and Its Association With Cartilage Matrix Composition 3 Years After Surgery

BACKGROUND

Anterior cruciate ligament tears can lead to posttraumatic osteoarthritis. In addition to biomechanical factors, changes in biochemical profiles within the knee joint after injury and anterior cruciate ligament reconstruction (ACLR) may play a role in accelerating joint degeneration. Hypothesis/Purpose: It was hypothesized that cartilage matrix composition after ACLR is associated with the degree of inflammatory response after initial injury. This study evaluated the association between the inflammatory response after injury-as indicated by cytokine, metalloproteinase, and cartilage degradation marker concentrations in synovial fluid-and articular cartilage degeneration, measured by T1ρ and T2 quantitative magnetic resonance imaging up to 3 years after ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Twenty-six subjects from a longitudinal cohort study who underwent ACLR at a mean 8.5 weeks after injury (range, 4-19 weeks) had synovial fluid aspirated at the time of surgery. Immunoassays quantified biomarkers in synovial fluid. T1ρ and T2 values of articular cartilage were calculated with magnetic resonance scans acquired prior to surgery and at 6 months and 1, 2, and 3 years after surgery. Pearson correlation coefficients were calculated among the various biomarkers. K-means clustering was used to group subjects with similar biomarker profiles. Generalized estimating equations were used to find the overall differences in T1ρ and T2 values throughout these first 3 years after surgery between the clusters while controlling for other factors.

RESULTS

Significant and strong correlations were observed between several cytokines (interleukin 6 [IL-6], IL-8, IL-10, and tumor necrosis factor α) and 2 matrix metalloproteinases (MMP-1 and MMP-3) ( P < .05). Moderate correlations were found among combinations of C-terminal crosslinked telopeptide type II collagen, N-terminal telopeptide, cartilage oligomeric matrix protein, and sulfated glycosaminoglycan ( P < .05). Two clusters were generated, 1 of which was characterized by lower concentrations of cytokines (IL-6, IL-8, IL-10, tumor necrosis factor α) and MMP-1 and MMP-3 and higher sulfated glycosaminoglycan. This cluster was associated with significantly higher T1ρ and T2 values in the medial tibial and patellar cartilage over the first 3 years after ACLR.

CONCLUSION

At the time of ACLR surgery, profiles of synovial fluid inflammatory cytokines, degradative enzymes, and cartilage breakdown products show promise as predictors of abnormal cartilage tissue integrity (increased T1ρ and T2 values) throughout the first 3 years after surgery.

CLINICAL RELEVANCE

The results suggest an intricate relationship between inflammation and cartilage turnover, which can in turn be influenced by timing after injury and patient factors.

Reproducibility measurements of three methods for calculating in vivo MR-based knee kinematics

PURPOSE

To describe three quantification methods for magnetic resonance imaging (MRI)-based knee kinematic evaluation and to report on the reproducibility of these algorithms.

MATERIALS AND METHODS

T2 -weighted, fast-spin echo images were obtained of the bilateral knees in six healthy volunteers. Scans were repeated for each knee after repositioning to evaluate protocol reproducibility. Semiautomatic segmentation defined regions of interest for the tibia and femur. The posterior femoral condyles and diaphyseal axes were defined using the previously defined tibia and femur. All segmentation was performed twice to evaluate segmentation reliability. Anterior tibial translation (ATT) and internal tibial rotation (ITR) were calculated using three methods: a tibial-based registration system, a combined tibiofemoral-based registration method with all manual segmentation, and a combined tibiofemoral-based registration method with automatic definition of condyles and axes. Intraclass correlation coefficients and standard deviations across multiple measures were determined.

RESULTS

Reproducibility of segmentation was excellent (ATT = 0.98; ITR = 0.99) for both combined methods. ATT and ITR measurements were also reproducible across multiple scans in the combined registration measurements with manual (ATT = 0.94; ITR = 0.94) or automatic (ATT = 0.95; ITR = 0.94) condyles and axes.

CONCLUSION

The combined tibiofemoral registration with automatic definition of the posterior femoral condyle and diaphyseal axes allows for improved knee kinematics quantification with excellent in vivo reproducibility.

T(1ρ) and T(2) quantitative magnetic resonance imaging analysis of cartilage regeneration following microfracture and mosaicplasty cartilage resurfacing procedures

PURPOSE

To examine T(1ρ) (T1rho) and T(2) quantitative magnetic resonance imaging (MRI) in evaluating cartilage regeneration following microfracture (MFx) and mosaicplasty (MOS) cartilage resurfacing procedures.

MATERIALS AND METHODS

Eighteen patients underwent MFx and eight patients underwent MOS to treat symptomatic focal cartilage defects. Quantitative T(1ρ) and T(2) maps were acquired at 3-6 months and 1 year after surgery. The area of resurfacing was identified, and T(1ρ) and T(2) values for the regenerated tissue (RT) and normal cartilage (NC) were acquired. RT/NC ratios were calculated to standardize absolute T(1ρ) and T(2) values. Data were prospective, cross-sectional, and nonrandomized.

RESULTS

T(1ρ) and T(2) showed good reanalysis reproducibility for RT and NC. Significant differences between RT and NC were present following MFx at 3-6 months for T(1ρ) and T(2) values as well as following MOS at 3-6 months and 1 year for T(1ρ) values. Following MFx, the T(2) RT/NC ratio was significantly different between 3-6 months and 1 year (P = 0.02), while the T(1ρ) RT/NC ratio approached significance (P = 0.07). Following MOS, the T(1ρ) and T(2) RT/NC ratios were not significantly different between the two timepoints.

CONCLUSION

T(1ρ) and T(2) MRI are complementary and reproducible methods for quantitatively and noninvasively monitoring regeneration of RT following MFx and MOS.

T1rho relaxation time of the meniscus and its relationship with T1rho of adjacent cartilage in knees with acute ACL injuries at 3 T

OBJECTIVE

The aim of this study was to assess the reproducibility of meniscus T1rho measurements, and to study T1rho relaxation time in the lateral meniscus (LM) and its relationship with adjacent cartilage T1rho in knees with acute anterior cruciate ligament (ACL) injuries at 3T magnetic resonance imaging.

METHOD

Quantitative assessment of the meniscus and cartilage was performed in 15 healthy controls and 16 ACL-injured patients using a T1rho mapping technique. All ACL-injured patients were imaged prior to surgery within 1-3 months of injury. The anterior and posterior horns of LM and medial meniscus (MM) were associated with partitioned weight-bearing cartilage sub-compartments (anterior, central, and posterior).

RESULTS

T1rho measurements in the meniscus showed excellent reproducibility (coefficient of variation (CV)<5%). Significantly elevated T1rho values were found in the LM in patients compared with controls (P<0.01). No differences were found in the MM. Significantly higher T1rho values were found at the posterior horn compared with the anterior horn of patients' meniscus (P=0.005). At the posterior sub-compartment of lateral tibia (LT), significantly increased cartilage T1rho values were found in patients compared with controls (P=0.002). A significant correlation (R(2)=0.47, P=0.007) was found between T1rho values of posterior horn of LM and T1rho values of posterior sub-compartment of LT cartilage in patients.

CONCLUSION

A strong injury-related relationship was demonstrated between meniscus and cartilage biochemical changes. T1rho mapping techniques provide tools to quantitatively evaluate meniscus and cartilage matrix in patients with ACL injuries.

Pre- and post-encephalitic neuropsychological profile of a 7-year-old girl

Our understanding of the neuropsychological effects of encephalitis has largely come from studies in which the level of premorbid functioning is estimated. Moreover, data on the neuropsychological effects of encephalitogenic pathogens other than the herpes simplex virus (HSV) are scant. We present the case of a 7-year-old girl who had intellectual and language assessment seven months prior to the onset of non-HSV encephalitis (possible aetiology: Mycoplasma pneumoniae), and again post-encephalitis. MRI post-illness demonstrated basal frontal, temporal and (limited) parietal damage. Details of speech, psychological and neuropsychological assessments were also documented. Pervasive changes were apparent in the domains of personality, behaviour, emotionality, attention, executive function, speech, language and memory. The patient's profile appears to differ most from that seen following typical HSV encephalitis with respect to marked executive and attentional difficulties. Her deficits appear to reflect both her acute basal brain injury and more diffuse insult, probably caused by postinfectious encephalitis.

CD40/154 blockade and rejection of islet allografts in the streptozotocin and autoimmune diabetic rat

Islet transplantation in children with autoimmune diabetes will require immunosuppression that has minimal toxicity and side-effects, and overcomes the barrier of autoimmunity. Since antibodies directed against the CD40/154 co-stimulatory pathway may meet these criteria, we have tested the ability of hamster antirat CD154 (AH.F5, Biogen) to prevent rejection of renal subcapsular islet allografts in streptozotocin (STZ) or autoimmune (AUTO) diabetic diabetes-resistant biobreeding (DRBB) rats. STZ diabetic rats that received anti-CD154 at 15 mg/kg per dose but not 10 mg/kg per dose did not have evidence of rejection until about 80-120 d post-transplantation, by which time antibody concentrations had returned to undetectable levels. Rats retreated with anti-CD154 before recurrence of diabetes had a prolonged period of disease-free survival. Most of these rats had recurrence following a spleen cell challenge. In contrast, AUTO diabetic DRBB rats treated with anti-CD154 had recurrence of diabetes between 7 and 12 d following transplantation of the Dark Agouti (DA) islets. In a separate set, AUTO diabetic rats that received a simultaneous islet isograft, islet allograft and thyroid allograft had focal accumulation of lymphocytes at the periphery of the isograft, while the islet and thyroid allografts had diffuse infiltration with lymphocytes and destruction of tissue with no residual staining for glucagon. Therefore, autoimmunity adds an additional barrier to islet allotransplantation that is not overcome with CD40/154 blockade in an animal model that closely parallels autoimmune diabetes in humans. The results indicate the importance of testing regimen of islet transplantation in animal models of autoimmune diabetes.

Structure of CD40 ligand in complex with the Fab fragment of a neutralizing humanized antibody

BACKGROUND

CD40 ligand (CD40L or CD154), a member of the tumor necrosis factor (TNF) family, plays a critical role in both humoral and cellular immune responses and has been implicated in biological pathways involving epithelial cells, fibroblasts, and platelets. Such a pathway is T cell-mediated B cell activation, a process that occurs through the interaction of CD40L with CD40 receptor expressed on B cells. It results in various B cell responses, including immunoglobulin isotype switching and B cell differentiation and proliferation. These responses can be inhibited by the monoclonal antibody 5c8, which binds with high affinity to CD40L.

RESULTS

To understand the structural basis of the inhibition, we determined the crystal structure of the complex of the extracellular domain of CD40L and the Fab fragment of humanized 5c8 antibody. The structure shows that the complex has the shape of a three-bladed propeller with three Fab fragments bound symmetrically to a CD40L homotrimer. To further study the nature of the antibody-antigen interface, we assessed the ability of 23 site-directed mutants of CD40L to bind to 5c8 and CD40 and analyzed the results in the context of the crystal structure. Finally, we observed via confocal microscopy that 5c8 binding to CD40L on the cell surface results in the formation of patches of clustered complexes.

CONCLUSIONS

The structure reveals that 5c8 neutralizes CD40L function by sterically blocking CD40 binding. The antigenic epitope is localized in a region of the surface that is likely to be structurally perturbed as a result of genetic mutations that cause hyper-IgM syndrome. The symmetric trimeric arrangement of the Fab fragments in the complex results in a geometry that facilitates the formation of large clusters of complexes on the cell surface.

Divalent cations stabilize the alpha 1 beta 1 integrin I domain

Recent structural and functional analyses of alpha integrin subunit I domains implicate a region in cation and ligand binding referred to as the metal ion-dependent adhesion site (MIDAS). Although the molecular interactions between Mn2+ and Mg2+ and the MIDAS region have been defined by crystallographic analyses, the role of cation in I domain function is not well understood. Recombinant alpha 1 beta 1 integrin I domain (alpha1-I domain) binds collagen in a cation-dependent manner. We have generated and characterized a panel of antibodies directed against the alpha1-I domain, and selected one (AJH10) that blocks alpha 1 beta 1 integrin function for further study. The epitope of AJH10 was localized within the loop between the alpha 3 and alpha 4 helices which contributes one of the metal coordination sites of the MIDAS structure. Kinetic analyses of antibody binding to the I domain demonstrate that divalent cation is required to stabilize the epitope. Denaturation experiments demonstrate that cation has a dramatic effect on the stabilization of the I domain structure. Mn2+ shifts the point at which the I domain denatures from 3.4 to 6.3 M urea in the presence of the denaturant, and from 49.5 to 58.6 degrees C following thermal denaturation. The structural stability provided to the alpha1-I domain by divalent cations may contribute to augmented ligand binding that occurs in the presence of these cations.

Comparison between the end-diastolic images and the summed images of gated 99mTc-sestamibi SPECT perfusion study in detection of coronary artery disease in women

BACKGROUND

End-diastolic images (EDI) can be easily derived from technetium 99m-sestamibi gated single photon emission computed tomography (SPECT) perfusion study (SGS). This may reduce the effect of myocardial wall thickening during systole and potentially improve the sensitivity of radionuclide perfusion imaging, especially in patients with small hearts.

METHODS

This prospective study was conducted in 53 consecutive female patients to compare the diagnostic accuracy of EDI with that of the summed images (SI) of SGS. Fifty-three patients with suspected coronary artery disease (CAD), scheduled for coronary angiography within 2 months, were evaluated with SGS. Treadmill stress testing was used in 28 patients, and dipyridamole injection was used in the remaining 25 patients. A 2-day protocol was used as follows: stress test with 25 to 30 mCi of 99mTc-sestamibi and a rest study performed at least 24 hours later with the same dose. Sixteen frames per cardiac cycle were acquired for both the rest and the stress studies. Three end-diastolic frames were used for EDI, and all the 16 frames were summed for SI. SI and EDI data reconstruction were interpreted by 3 experienced blinded observers (consensus reading) during two distinct reading sessions, one with SI alone and the second with EDI alone. The heart was divided into 17 segments.

RESULTS

Coronary angiography showed > or = 50% stenoses in 1 or more major coronary arteries in 38 patients and was normal in 15 patients. The sensitivity was 73.7% (28/38) and 84.2% (32/38), respectively, for SI and EDI. Three of 4 patients with CAD not detected by SI but seen with EDI were considered to have relatively small hearts. The specificity was 86.7% (13/15) and 80.0% (12/15) for SI and EDI, respectively. On a total of 901 segments, 106 ischemic defects were detected by SI and 173 by EDI (P = .001). The segmental agreement between the two techniques was 88.6% (798/901 segments).

CONCLUSION

EDI showed more ischemic defects than SI, and there was also a nonsignificant trend toward an improved sensitivity of EDI in comparison to SI in detection of coronary artery disease in women, especially in patients with small hearts. EDI may be a useful adjunct to the standard perfusion imaging with SGS in such a clinical situation.

Pharmacokinetics/dynamics of 5c8, a monoclonal antibody to CD154 (CD40 ligand) suppression of an immune response in monkeys

The pharmacokinetics and pharmacodynamics (PK/PD) of chimeric (Ch5c8) and humanized (Hu5c8) 5c8, a monoclonal antibody that binds CD154 (CD40 ligand), thus blocking the interaction between CD40 and CD154, were investigated in cynomolgus monkeys. Single-dose groups (n = 3 animals per dose) received saline, 0.2, 1, 5 or 20 mg/kg i.v. doses of Hu5c8. The repeat-dose groups (n = 4 animals) received 0 or 5 mg/kg i.v. doses of Ch5c8 or Hu5c8 on days 1, 2, 3, 5, 7 and 9. The single-dose PK parameters showed dose proportionality, with a terminal half-life of 300 h, a volume of distribution at steady state of 73 ml/kg and clearance of 0.2 ml.h-1.kg-1. The repeat-dose regimen produced a longer terminal half-life (500 h) and lower clearance (0.13 ml.h-1.kg-1) than in the single-dose groups. The antibody titer to tetanus toxoid (ATT) challenge served as the immunodynamic marker. The primary ATT response consisted of a latent phase of approximately 10 days, during which the immune system was processing antigen but not yet producing antibody, a rise to an antibody maximum titer at approximately 18 days and a decline toward baseline by approximately 40 days in controls. The 5c8 produced a log(dose)-proportional reduction in the area under the curve of ATT. An indirect PK/PD model based on the kinetics of tetanus toxoid exposure and inhibition of ATT production in relation to 5c8 concentrations was developed. A median inhibitory concentration of 0.84 microg/ml and a efficacy of 0.84 reflected marked inhibition of ATT response by 5c8. The model provides quantitation of reduced ATT responses after 5c8 and was applicable to primary and secondary immune responses and to both single-dose and multiple-dose treatments. The monoclonal antibody 5c8 blocks the CD40 and CD154 interaction, producing consistent and substantive reduction in antibody formation after administration of tetanus toxoid, which can be characterized with PK/PD modeling. It is anticipated that 5c8 may have utility in the treatment of antibody-mediated autoimmune disease.

Inhibition of alpha interferon but not gamma interferon signal transduction by phorbol esters is mediated by a tyrosine phosphatase

Previous studies have indicated that the expression of viral oncoproteins, cell transformation, or phorbol ester treatment of cells can inhibit alpha/beta interferon (IFN-alpha/beta)-induced gene expression. The mechanisms by which these promoters of cell growth exert their inhibitory effects vary, but in most instances they involve a disruption of the IFN-alpha/beta-induced transcription complex ISGF3 such that the DNA-binding component of this complex (the 48-kDa ISGF3gamma protein) does not bind to the interferon-stimulated response element (ISRE). In this report, we demonstrated that phorbol ester treatment of human peripheral blood monocytes dramatically inhibits activation of IFN-alpha/B-stimulated early response genes but by a mechanism which does not involve abrogation of the ISRE binding of ISGF3gamma. Phorbol ester treatment of monocytes inhibited IFN alpha-stimulated tyrosine phosphorylation of the transcription factors Stat1alpha, Stat2, and Stat3 and of the tyrosine kinase Tyk2 but had no effect on IFN-gamma activation of Stat1alpha. IFNalpha-stimulated tyrosine phosphorylation of Jak1 and the alpha subunit of the IFN-alpha receptor were unaffected by phorbol 12-myristate 13-acetate (PMA). Moreover, PMA caused the dephosphorylation of Tyk2 but not of Jak1, which was activated by IFN. Pretreatment of cells with vanadate prevented the effects of PMA with regard to PMA-induced Tyk2 dephosphorylation. These observations suggest that PMA exerts its inhibitory effects by activation of a tyrosine phosphatase which selectively regulates Tyk2 but not Jak1 activity.

Requirement for MAP kinase (ERK2) activity in interferon alpha- and interferon beta-stimulated gene expression through STAT proteins

Activation of early response genes by interferons (IFNs) requires tyrosine phosphorylation of STAT (signal transducers and activators of transcription) proteins. It was found that the serine-threonine kinase mitogen-activated protein kinase (MAPK) [specifically, the 42-kilodalton MAPK or extracellular signal-regulated kinase 2 (ERK2)] interacted with the alpha subunit of IFN-alpha/beta receptor in vitro and in vivo. Treatment of cells with IFN-beta induced tyrosine phosphorylation and activation of MAPK and caused MAPK and Stat1 alpha to coimmunoprecipitate. Furthermore, expression of dominant negative MAPK inhibited IFN-beta-induced transcription. Therefore, MAPK appears to regulate IFN-alpha and IFN-beta activation of early response genes by modifying the Jak-STAT signaling cascade.

Somatic mosaicism in sperm is associated with intergenerational (CAG)n changes in Huntington disease

We have analysed the CAG repeat in the Huntington disease (HD) gene in sperm and blood from 20 unrelated HD patients. Although the CAG repeat displayed significant mosaicism in sperm from all individuals, there were marked differences in the degree of repeat instability. Individuals who had either inherited or transmitted an expanded CAG repeat displayed the highest levels of repeat mosaicism, whereas individuals who had inherited or transmitted a contracted repeat had very limited CAG mosaicism in sperm. A strong association between intergenerational change in CAG allele size and the level of sperm repeat mosaicism was determined (P = 0.019). In contrast, neither blood CAG size nor repeat mosaicism in blood, were significantly associated with intergenerational CAG changes. These data suggest the presence of a cis-acting factor, separate from CAG size, that strongly influences the intergenerational behaviour of the CAG repeat. Additional studies are needed to determine whether analysis of CAG mosaicism in sperm is useful for assessing an individual's risk for transmitting large expansions or contractions to his offspring.

Solution-phase binding of monoclonal antibodies to bee venom phospholipase A2

The binding of monoclonal anti-bee venom phospholipase A2 antibodies to their antigen was monitored by size-exclusion high performance liquid chromatography. As judged by this panel of six antibodies, honeybee venom phospholipase A2 contains five binding sites, three of which are completely independent epitopes. The study revealed that this PLA2 can accommodate three different antibodies simultaneously. The results demonstrate the utility of size-exclusion high performance liquid chromatography in epitope analyses, such as its ability to compare the relative expansiveness and conformational state of the epitopes and to enumerate the antibodies that the antigen can accommodate simultaneously. The data provide compelling evidence that one of the monoclonal antibodies, M5 (which activates the enzyme), recognizes a different conformation of phospholipase A2 than do the other antibodies. The results also demonstrate that different pairs of monoclonal antibodies differ in their predilection to form high molecular weight complexes with the antigen.

Myocardial technetium 99m-labeled sestamibi single-photon emission computed tomographic imaging in the detection of coronary artery disease: comparison between early (15 minutes) and delayed (60 minutes) imaging

BACKGROUND

Previous studies have demonstrated that there is a "partial" myocardial redistribution of 99mTc-labeled sestamibi (MIBI) between 1 and 3 hours after intravenous injection at stress. The purpose of this prospective study was to compare MIBI single-photon emission computed tomographic (SPECT) imaging performed 15 and 60 minutes after the injection at stress in the detection of coronary artery disease.

METHODS AND RESULTS

Thirty-five patients with coronary artery disease (26 underwent coronary angiography and 23 had a positive 201Tl study result) were included in this study. SPECT imaging started 15 minutes after the injection of 25 to 30 mCi MIBI at peak stress (180-degree arc, 32 angles, 25 sec/view, and high-resolution collimator). Patients underwent reimaging at 60 minutes according to the same protocol and with the same gamma camera. A rest study was obtained 75 minutes after the injection of MIBI (25 to 30 mCi) at rest, 48 hours later. Images (divided for a total of 19 segments per patient) were interpreted by two blinded observers for patient diagnosis and segmental comparison. The patient diagnosis was the same for the two protocols: normal = 3, ischemia = 27, and scar = 5. The segmental agreement (kappa = 0.90) was 632/665 (95.0%). The imaging performed at 15 minutes detected normal, ischemia, and scar in 413, 189, and 63 segments, respectively, whereas the imaging performed at 60 minutes detected 422, 180, and 63 segments, respectively (difference not significant). The early and delayed images were placed side by side for subjective comparison of the extent of the defect. Early imaging showed slightly larger defects in six patients, equal defects in 24 patients, and slightly smaller defects in five patients. Ischemic/normal wall ratios were 0.67 +/- 0.16 at 15 minutes and 0.68 +/- 0.15 at 60 minutes.

CONCLUSIONS

There is no clinically significant difference between SPECT imaging performed at 15 minutes or 60 minutes after the injection of MIBI at stress. Furthermore, this study showed that it is feasible to obtain good-quality MIBI images even 15 minutes after the injection at stress.

Thallium-201-dipyridamole imaging: comparison between a standard dose and a high dose of dipyridamole in the detection of coronary artery disease

The purpose of this study was to compare two different doses of dipyridamole as a pharmacologic stress test for 201Tl imaging.

METHODS

Twenty-four patients with significant coronary artery disease (15 had undergone a coronary angiogram and 9 had undergone a previous 201Tl study with a significant lesion) were prospectively studied. Within 1 wk, all patients underwent two 201T-dipyridamole myocardial planar studies, one using a standard dose (STD) and the other, a high dose (HIGH) of dipyridamole. The protocol order was randomly assigned. The STD protocol used a dose of 0.14 mg/kg/min for a duration of 4 min (0.56 mg/kg), and the HIGH protocol used a dose of 0.14 mg/kg min for a duration of 6 min (0.84 mg/kg). The 201Tl was injected 3 min after the end of the dipyridamole infusion. Images, obtained 5 min and 4 hr later, were interpreted (divided into five segments each) by three blinded observers.

RESULTS

The STD protocol showed normal, ischemia and scar in 252, 91 and 17 segments, respectively. The HIGH protocol detected 232, 118 and 10 segments, respectively. A side-by-side evaluation was done to evaluate the defect extent subjectively, which was greater with HIGH in 14, equal in six and smaller in four patients. One or more side effects were seen in 14 patients with STD and in 19 with HIGH. Increased heart rate (8 bpm for STD and 19 bpm for HIGH, p < 0.001) was the only significant change seen in the hemodynamic parameters.

CONCLUSION

This preliminary study indicates that a high dose of dipyridamole seems to be safe and can be helpful to increase the sensitivity of 201Tl imaging.

Respiratory morbidity in Merseyside schoolchildren exposed to coal dust and air pollution

A cross sectional study was carried out to determine whether schoolchildren in a specific locality exposed to pollution from steam coal dust have an excess of respiratory symptoms compared with children in control areas. A total of 1872 primary schoolchildren (aged 5-11 years) from five primary schools in the Bootle dock area of Liverpool (exposed area), five primary schools in South Sefton (control area), and five primary schools in Wallasey (control area) were studied. A questionnaire was distributed through the schools and was completed by the parents of the children. The questionnaire inquired about respiratory symptoms (cough, wheezing, and shortness of breath), allergy, atopy, smoking, and socioeconomic factors. Height, weight, and peak expiratory flow were measured. Compliance was good (92%) and similar in the three study areas. The children in the three areas were of similar mean age (7.5 years), height (1.24 m), sex ratio, and had a similar prevalence of paternal (6.2%) and maternal (7%) asthma. The exposed zone contained more unemployed parents (41, 29, and 29% respectively), more rented housing (64, 45, 34%), and more smoking parents (71, 60, 59%) than the control areas. Respiratory symptoms were significantly more common in the exposed area, including wheeze (25.0, 20.6, and 17.5%), excess cough (40.0, 23.4, and 25.1%), and school absences for respiratory symptoms (47.5, 35.9, and 34.9%). These differences remained significant even if the groups were subdivided according to whether or not parents smoked or were employed. Multiple logistic regression analysis confirmed the exposed zone as a significant risk factor for absenteeism from school due to respiratory symptoms (odds ratio 1.55, 95% confidence interval 1.17 to 2.06) after adjusting for confounding factors. Standard dust deposit gauges on three schools confirmed a significantly higher dust burden in the exposed zone. An increased prevalence of respiratory symptoms in primary schoolchildren exposed to coal dust is confirmed. Although the association with known coal dust pollution is suggestive a cross sectional study cannot confirm a casual relation and further studies are needed.

Treatment of breast cancer in the Auckland region 1976-85

AIM

A descriptive study of the treatment of breast cancer in Auckland between the years 1976 to 1985.

METHODS

A database was constructed utilising information from all new breast cancer cases recorded in the Auckland region from September 1976 to September 1985. Details of treatment were obtained at the time of diagnosis and the database was updated every 9 months. Patient survival was measured and changes in the pattern of treatment were assessed.

RESULTS

After a median follow up of 9 years 41% of patients were alive without evidence of breast cancer, 9% were alive with recurrence and 50% had died, 38% having died of breast cancer. Survival of node positive patients at 5 years of follow up who received adjuvant tamoxifen or adjuvant chemotherapy was 57 (SE 4)% and 63 (4)% respectively. The proportion of less than mastectomy surgical procedures increased over the study period, and local recurrence in these patients was reduced by postoperative radiotherapy.

CONCLUSIONS

Between 1976 and 1985 there was an increasing rate of conservative surgery for breast cancer in Auckland. Overall survival of patients was comparable to that reported in international studies, with increasing use of adjuvant endocrine therapy but a decline in adjuvant chemotherapy over the duration of the study.

Leukocyte accumulation promoting fibrin deposition is mediated in vivo by P-selectin on adherent platelets

The glycoprotein P-selectin is a cell adhesion molecule of stimulated platelets and endothelial cells, which mediates the interaction of these cells with neutrophils and monocytes. It is a membrane component of cell storage granules, and is a member of the selectin family which includes E-selectin and L-selectin. P-selectin recognizes both lineage-specific carbohydrate ligands on monocytes and neutrophils, including the Lewis x antigen, sialic acid, and a protein component. In inflammation and thrombosis, P-selectin may mediate the interaction of leukocytes with platelets bound in the region of tissue injury and with stimulated endothelium. To evaluate the role of P-selectin in platelet-leukocyte adhesion in vivo, the accumulation of leukocytes within an experimental thrombus was explored in an arteriovenous shunt model in baboons. A Dacron graft implanted within an arteriovenous shunt is thrombogenic, accumulating platelets and fibrin within its lumen. These bound platelets express P-selectin. Here we show that antibody inhibition of leukocyte binding to P-selectin expressed on platelets immobilized on the graft blocks leukocyte accumulation and inhibits the deposition of fibrin within the thrombus. These results indicate that P-selectin is an important adhesion molecule on platelets, mediating platelet-leukocyte binding in vivo, that the presence of leukocytes in thrombi is mediated by P-selectin, and that these leukocytes promote fibrin deposition.

Human vascular endothelial cell adhesion receptors for Plasmodium falciparum-infected erythrocytes: roles for endothelial leukocyte adhesion molecule 1 and vascular cell adhesion molecule 1

The clinical complications associated with severe and cerebral malaria occur as a result of the intravascular mechanical obstruction of erythrocytes infected with the asexual stages of the parasite, Plasmodium falciparum. We now report that a primary P. falciparum-infected erythrocyte (parasitized red blood cell [PRBC]) isolate from a patient with severe complicated malaria binds to cytokine-induced human vascular endothelial cells, and that this adhesion is in part mediated by endothelial leukocyte adhesion molecule 1 (ELAM-1) and vascular cell adhesion molecule 1 (VCAM-1). PRBC binding to tumor necrosis factor alpha (TNF-alpha)-activated human vascular endothelial cells is partially inhibited by antibodies to ELAM-1 and ICAM-1 and the inhibitory effects of these antibodies is additive. PRBCs selected in vitro by sequential panning on purified adhesion molecules bind concurrently to recombinant soluble ELAM-1 and VCAM-1, and to two previously identified endothelial cell receptors for PRBCs, ICAM-1, and CD36. Post-mortem brain tissue from patients who died from cerebral malaria expressed multiple cell adhesion molecules including ELAM-1 and VCAM-1 on cerebral microvascular endothelium not expressed in brains of individuals who died from other causes. These results ascribe novel pathological functions for both ELAM-1 and VCAM-1 and may help delineate alternative adhesion pathways PRBCs use to modify malaria pathology.

Structure/function studies on vascular cell adhesion molecule-1

Vascular cell adhesion molecule-1 (VCAM1) is a member of the immunoglobulin (Ig) superfamily which interacts with the integrin very late antigen-4 (VLA4). The VCAM1/VLA4 interaction mediates both adhesion and signal transduction and is thought to play an important role in inflammatory and immune responses in vivo. The major form of human VCAM1 contains seven extracellular Ig-like domains, with domain 1 designated as the most N-terminal. We have examined the relationship between human VCAM1 structure and function using a combination of domain truncation mutants and proteolytic fragmentation of recombinant soluble VCAM1. We have characterized two regions of VCAM1, localized to domains 4 and 5, which are highly sensitive to proteolytic cleavage, localized the epitope of the blocking monoclonal antibody 4B9 to domain 1, and found that domains 1-3 are sufficient for both its adhesive function and its ability to initiate T cell activation.

Expression of vascular adhesion molecules in inflammatory bowel disease

The expression of the vascular adhesion molecules ELAM-1 (endothelial leukocyte adhesion molecule 1) and VCAM-1 (vascular cell adhesion molecule 1) was evaluated in colonic mucosa of patients with inflammatory bowel disease and normal controls by immunocytochemistry. VCAM-1 was found to be constitutively expressed in lymphoid aggregates in normal colonic mucosa and was not significantly enhanced or altered in distribution in mucosa of patients with inflammatory bowel disease regardless of the activity of the inflammatory process. In contrast, ELAM-1 was not detected by these techniques in normal colonic mucosa (n = 11) or in colonic mucosa of patients with inflammatory bowel disease which was either uninvolved or quiescent (n = 30). However, high levels of ELAM-1 were consistently found on endothelial surfaces in association with active inflammation in affected areas of colonic mucosa in patients with either ulcerative colitis (n = 27) or Crohn's colitis (n = 9). In addition, ELAM-1 appeared to be present within neutrophils which had migrated into crypt abscesses in affected mucosa. Similar analysis was carried out in the cotton-top tamarin (CTT), a primate that experiences an idiopathic chronic diffuse colitis resembling human ulcerative colitis. Although anti-human VCAM-1 antibodies did not react with the CTT, anti-human ELAM-1 stained endothelial surfaces in mucosal biopsies from CTT with active colitis. No ELAM-1 was identified in mucosa of CTT in which colitis activity was quiescent. Thus ELAM-1 is expressed on colonic endothelial surfaces in association with inflammation and may play an important role in facilitating leukocyte migration into sites of active IBD involvement.

Subliminal psychodynamic activation: updated comprehensive list of experimental results and comments on previous lists

A comprehensive list of results from visual subliminal psychodynamic activation experiments is presented. This list includes results reported since the publication of the last comprehensive list by Weinberger and Hardaway in 1990 and several results not found on that list. On the present list, SPA results are categorized according to criteria that we contend are more objective than those used previously. In contrast to conclusions drawn from previous lists prepared by Silverman in 1980 and 1983, by Weinberger and Hardaway in 1990, and by Weinberger and Silverman in 1987, the present list indicates that the results of a majority of experiments do not clearly support hypotheses tested by the subliminal psychodynamic activation method. Aspects of Hardaway's meta-analyses from 1987 and 1990 for major areas of research on subliminal psychodynamic activation are discussed in terms of suggestions for further research.

'Continuous adaptation' method aligns I/S with corporate goals

Flexibility allows hospitals to meet their goals head on, grapple with problems and find solutions as a team. Claire Benjamin and Annette Valenta propose a managerial method that links the corporate strategic plan with experts who can best implement and use tomorrow's information tools.

Review of auditory subliminal psychodynamic activation experiments

Subliminal psychodynamic activation experiments using auditory stimuli have yielded only a modicum of support for the contention that such activation produces predictable behavioral changes. Problems in many auditory subliminal psychodynamic activation experiments indicate that those predictions have not been tested adequately. The auditory mode of presentation, however, has several methodological advantages over the visual one, the method used in the vast majority of subliminal psychodynamic activation experiments. Consequently, it should be considered in subsequent research in this area.

Expression and functional characterization of a soluble form of vascular cell adhesion molecule 1

Vascular cell adhesion molecule 1 (VCAM1) is a leukocyte adhesion molecule induced on human endothelium in vitro and in vivo by inflammatory stimuli. A truncated cDNA for VCAM1 was constructed, stably expressed in Chinese Hamster Ovary (CHO) cells, and the secreted recombinant soluble form of VCAM1 (rsVCAM1) purified to homogeneity by immunoaffinity chromatography. Immobilized rsVCAM1 is a functional adhesion protein, and selectively binds only VLA4-expressing cells, including human B and T lymphocytes, NK cells, and certain lymphoblastoid cell lines. T cell subset analyses indicate preferential binding of CD8+ memory cells. rsVCAM1 should prove valuable for the further study of the role of VCAM1 during inflammatory and immune responses in vivo.

Von Hippel-Lindau disease: a genetic study

Genetic aspects of von Hippel-Lindau (VHL) disease were studied in familial and isolated cases. Complex segregation analysis with pointers was performed in 38 kindreds with two or more affected members. Dominant inheritance with almost complete penetrance in the highest age classes (0.96 at 51 to 60 and 0.99 at 61 to 70 years) was confirmed and there was no evidence of heterogeneity between families ascertained through complete and incomplete selection. The point prevalence of heterozygotes in East Anglia was 1.89/100,000 (1/53,000) persons with an estimated birth incidence of 2.73/100,000 (1/36,000) live births. Reproductive fitness was 0.83. Direct and indirect estimates of the mutation rate were 4.4 (95% CI 0.9 to 7.9) x 10(-6)/gene/generation and 2.32 x 10(-6)/gene/generation respectively. There was no significant association between parental age or birth order and new mutations for VHL disease.

Human monocytes bind to two cytokine-induced adhesive ligands on cultured human endothelial cells: endothelial-leukocyte adhesion molecule-1 and vascular cell adhesion molecule-1

Vascular cell adhesion molecule-1 (VCAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1) are adhesive proteins induced on endothelium by cytokines. We examined the contribution of these adhesive proteins to human peripheral blood monocyte adherence to endothelium using transfected Chinese hamster ovary (CHO) cells stably expressing these proteins and monoclonal antibodies (MoAbs) to ELAM-1, VCAM-1, or CD49d/CD29 (VLA-4), the leukocyte receptor for VCAM-1. Monocytes bound to CHO cells transfected with cDNA of ELAM-1 or VCAM-1. Binding to ELAM-1 was inhibited by MoAb to ELAM-1 and binding to VCAM-1 was inhibited by MoAb to VCAM-1 or the alpha-chain of very late activation antigen-4 (VLA-4) (CD49d). Additive inhibition of adherence to unstimulated human umbilical vein endothelium (HUVE) was observed when monocytes were pretreated with both MoAb to CD49d and MoAb to CD18, the common beta-chain of the leukocyte beta 2 integrin receptors. Adherence of monocytes to HUVE stimulated by recombinant human tumor necrosis factor-alpha was not reduced by MoAbs to CD18, CD49d, or ELAM-1 when used singly, but combinations of these MoAbs produced significant inhibition. We conclude that multiple receptor-ligand systems are involved in monocyte adherence to endothelium.

Phobic anxiety and clumsiness in a 10-year-old girl

During assessment of a girl with a long-standing phobic state, it was found that she also had previously unrecognised perceptuo-motor problems, which were associated with continuing problems in balance and spatial awareness. Her phobia improved after a desensitisation programme, but the physical disorder persisted, despite physiotherapy. The authors conclude that the girl's phobic anxiety may have had its origin in her experience of the perceptual disorder during development.