Motivation to hide emotion and children's understanding of the distinction between real and apparent emotions

The authors investigated the extent to which children's understanding of the distinction between real and apparent emotions varied according to the motivation to hide emotions. Children, aged 6-7 and 10-11 years, were read stories designed to elicit either prosocial or self-protective motivated display rules and were asked to predict the facial expressions the protagonists would make to hide felt emotions. Children were found to understand the distinction between real and apparent emotions very well, independently of the type of motivation. Contrary to predictions, boys understood this distinction better than did girls when the motivation to hide positive emotions was prosocial. Children perceived neutralization as the most appropriate strategy to hide felt emotions, followed by masking.

[Study of psychometric properties of two new questionnaires assessing beliefs in hypochondriasis in a non-clinical population]

Most instruments focussing on hypochondriasis symptoms do not have for goal to assess beliefs specifically. Instead, these instruments are used to measure specific behaviors. To assess underlying beliefs with these kinds of instruments, you have to extract false beliefs by deduction. In cognitive therapy, it is important to target erroneous beliefs in order to change them. On the other hand, existing instruments are not really suitable to target erroneous health beliefs. Even if some questionnaires are built to assess beliefs directly, it seems that they only measure the conviction of having an illness and do not assess the general health beliefs present in excessive health worriers. However, many researchers argue that this other kind of beliefs are the ones responsible in maintaining hypochondriasis symptoms. Presently, researchers assume that erroneous beliefs can maintain worries about illness among people with hypochondriasis symptoms like false beliefs about worry maintain worries in people with General Anxiety Disorder (GAD). Even if the importance of false beliefs in the maintenance of pathological worries is now recognized, most instruments on hypochondriasis symptoms do not have for goal to assess erroneous beliefs concerning worry about health. For instance, although the questionnaire Why do people worry? (WW) shows good psychometric properties and measures beliefs related to general worries, this questionnaire is not specific enough to correctly evaluate beliefs associated to health worry. A new questionnaire has to emerge in order to assess false beliefs associated to worry about health. This manuscript presents the development and the validation of a new questionnaire: the General Health Beliefs Questionnaire (GHBQ) that assesses general health beliefs, and also presents the development and the validation of a new questionnaire assessing beliefs associated to worry about health: the Why do people Worry about Health? (WW-H) . In this study, the GHBQ's and the WW-H's psychometric qualities and the factorial structure were assessed. More precisely, this study examined the factorial structure, the temporal stability, the convergent, divergent and criteria validities of the GHBQ and the WW-H. Four hundred and twenty nine French-speaking university students (non-clinical participants) completed a battery of questionnaires at the beginning of a class. The questionnaires were: The General Health Beliefs Questionnaire (GHBQ), the Why do people Worry about Health (WW-H), the Illness Worry Scale (IWS), the Beck Depression Inventory-short form (BDI-short form) and the Beck Anxiety Inventory (BAI). A second administration took place three weeks later with the same sample to test the temporal stability of the GHBQ and the WW-H. The principal component analysis with orthogonal rotation (varimax) supports a five components solution for the GHBQ: 1) magical thinking, 2) health, 3) consequences, 4) responsibility, and 5) vulnerability. The principal component analysis with oblique rotation (direct oblimin) (d=0) found a two components solution for the WW-H: 1) utility and 2) magical thinking associated to worries about health. The internal consistency of the GHBQ and the WW-H is excellent (a=.80 and a=.90, respectively). A correlation of 0.49 was found between the GHBQ and the WW-H. The correlation between the GHBQ and the IWS who evaluates the tendency to worry (r=.50) and between the WW-H and the IWS (r=.49) showed that the convergent validity of these questionnaires is adequate. On a three weeks interval, the GHBQ (r=.70) and the WW-H (r=.71) showed a satisfying temporal stability. The means of the high worriers (80 superior percentile at the IWS) (M=38.8, ET=8.93) and the means of the moderate worriers (between the 40 and the 60 percentile at the IWS) (M=32.8, ET=8.00) on the GHBQ have been compared. A significant difference has been found between the two groups [F(1,181)=23,129, p<0,001]. Also, the means of the high worriers (M=27.3, ET=8.59) and the means of the moderate worriers (M=23.8, ET=8.56) on the WW-H haveave been compared. An ANOVA has found a significant difference between these two groups [F(1,180)=7,396, p=0,007]. These results show that general health beliefs and false beliefs associated to worry about health are more often present in high worriers than in moderate worriers. The GHBQ and the WW-H allow psychologists, physicians and psychiatrists to do a quicker and more exhaustive evaluation of general health beliefs and false beliefs associated to worry about health, in less costs. These questionnaires will improve the chances of success of the hypochondriasis' treatment by helping clinicians to detect and correct false beliefs more easily.

Perception of genuine and masking smiles in children and adults: sensitivity to traces of anger

The authors examined children's and adults' sensitivity to traces of anger in masking smiles by presenting participants with short video excerpts of smiles that differed by the intensity of an anger component. Fifty-two children, aged 6 to 12 years, and 26 adults were asked to judge whether a stimulus person was really happy or pretending to be happy. Six- and 7-year-old children were found to be sensitive to traces of anger, but less so than older children and adults. Researchers found evidence of explicit knowledge of the emotion hidden in masking smiles only in adult participants.

Renormalization group in quantum mechanics at zero and finite temperature

We apply the renormalization group formalism, to integrate quantum fluctuations of quantum mechanical systems at zero and finite temperature. At zero temperature a nonperturbative renormalization group equation allows to compute the ground state energy whereas at finite temperature a variational renormalization group equation is proposed to compute the free energy.

[Evaluation of worry: validation of a French translation of the Penn State Worry Questionnaire]

Excessive worry, which is the central feature of Generalized Anxiety Disorder (GAD), is recognized as an important clinical phenomenon with many negative consequences on people's health. For example, studies report that excessive worry is associated with higher frequencies of work absenteeism and medical consultations, increased risk of other anxiety disorders, depression, heart disease, diabetes and cancer. It is thus imperative to develop effective measures to assess worry among adult. Until now, no measures were available in French for the practitioners and researchers to evaluate the tendency to engage in excessive and uncontrollable worry. One of the most frequently used questionnaires to assess worry in English is The Penn State Worry Questionnaire (PSWQ). This self-report measure has been widely studied and has shown excellent psychometric properties among the non-clinical and clinical populations. This manuscript presents the results of three studies evaluating the psychometric properties of a French Translation of the PSWQ, the Questionnaire sur les Inquiétudes de Penn State (QIPS). The first study includes the translation procedures used to create the French version of the questionnaire, the factorial structure, the internal consistency, the quality of the items, and the convergent validity among non-clinical participants. The second study examines the temporal stability, and the convergent and divergent validity of the questionnaire. Finally, the third study investigates the internal consistency, the quality of the items, and the convergent and divergent validity of the questionnaire among GAD patients. Study 1. This study describes the translation procedures used to create the QIPS, the factorial structure, the internal consistency, the quality of the items, and the convergent validity among non-clinical participants. The French version was translated by a group of clinical psychologists with the assistance of a professional translator and a linguist. A back translation procedure was also conducted. Finally, a pilot study confirmed the intelligibility of the questionnaire. French-speaking university students (N = 352) completed a battery of questionnaires during a lecture. The questionnaires were: The Questionnaires sur les Inquiétudes de Penn State, the Intolerance of Uncertainty Questionnaire, the Cognitive Avoidance Questionnaire, the Why Worry Questionnaire-Revised, and the Social Problem-Solving Inventory-Revised. The statistical analyses reveal that the QIPS shows an appropriate factorial structure, an excellent internal consistency and a very good convergent validity. This French Questionnaire thus seems to be suitable to assess the tendency to worry among the nonclinical population. Study 2. This second study examines the temporal stability, and the convergent and divergent validity of the QIPS. The sample includes 95 French-speaking University students who volunteered to complete the QIPS and the Beck anxiety Inventory. Two self-rating questions were also asked to evaluate the percentage of time spent worrying and to what extent does worrying causes a problem. Eighty-six students participated at the second administration of the questionnaires, four weeks later. The results indicate that the QIPS is very stable over time, thus supporting its temporal stability. Different correlations confirm its convergent and divergent validity. It is concluded that the QIPS is a suitable measure of worry in a non-clinical population. Study 3. This study investigates the internal consistency, the quality of the items, and the convergent and divergent validity of the questionnaire among GAD patients. Seventy-seven GAD patients, as defined by the Diagnostic and Statistical Manual of Mental disorders, fourth edition (DSM IV), participated in this study. They completed the QIPS, the Worry Domains Questionnaire, The Worry and Anxiety Questionnaire, the Intolerance of Uncertainty Questionnaire, the Beck Anxiety Inventory, the Beck Depression Inventory, and a daily diary of differents aspects of worry. The results reveal that the QIPS has an excellent internal consistency, a very good convergent and divergent validity. The QIPS thus seems to be suitable to assess the tendency to worry among GAD patients.

CONCLUSION

The overall results presented in these studies confirm the excellent psychometric properties of the QIPS. This French questionnaire is a useful tool for clinicians and researchers to assess the tendency to worry among non-clinical and clinical populations.

Facial morphology and children's categorization of facial expressions of emotions: a comparison between Asian and Caucasian faces

The effects of Asian and Caucasian facial morphology were examined by having Canadian children categorize pictures of facial expressions of basic emotions. The pictures were selected from the Japanese and Caucasian Facial Expressions of Emotion set developed by D. Matsumoto and P. Ekman (1989). Sixty children between the ages of 5 and 10 years were presented with short stories and an array of facial expressions, and were asked to point to the expression that best depicted the specific emotion experienced by the characters. The results indicated that expressions of fear and surprise were better categorized from Asian faces, whereas expressions of disgust were better categorized from Caucasian faces. These differences originated in some specific confusions between expressions.

Experimental manipulation of intolerance of uncertainty: a study of a theoretical model of worry

Intolerance of uncertainty has been identified as an important variable related to worry and Generalized Anxiety Disorder (GAD) [Dugas, M. J., Gagnon, F., Ladouceur, R., & Freeston, M. H. (1998). Generalized anxiety disorder: a preliminary test of a conceptual model. Behaviour Research and Therapy, 36, 215-226; Ladouceur, R., Dugas, M. J., Freeston, M. H., Rhéaume, J., Blais, F., Boisvert, J.-M., Gagnon, F., & Thibodeau, N. (1999). Specificity of Generalized Anxiety Disorder symptoms and processes. Behavior Therapy, 30, 197-207]. The goal of the present study was to clarify the relationship between this cognitive process and worry by experimentally manipulating intolerance of uncertainty. A gambling procedure was used to increase intolerance of uncertainty in one group (N = 21) and to decrease intolerance of uncertainty in another group (N = 21). The results indicate that participants whose level of intolerance of uncertainty was increased showed a higher level of worry, compared to participants whose level of intolerance of uncertainty was decreased. These results provide some initial clarifications as to the causal nature of the link between intolerance of uncertainty and worry. These results are coherent with our theoretical model of worry and GAD (Dugas et al., 1998), which stipulates that intolerance of uncertainty plays a key role in the acquisition and maintenance of excessive worry.

Characterization of the Ly49I promoter

Fourteen potential Ly49 genes have been identified in the C57B1/6 mouse strain, and cDNAs containing a complete coding region have been isolated for 10 members of this gene family. Ly49 proteins are primarily expressed in natural killer (NK) cells. Although the sequence of the Ly49a promoter region has been published, no study of the cell-specific activity of the promoter has been reported. A 12-kb genomic fragment of the Ly49I gene was isolated and characterized by DNA sequencing. Approximately 5 kb of DNA sequence upstream of the first Ly49I exon was determined and this region was used to perform promoter analysis using luciferase reporter plasmid constructs. A core promoter was identified that was preferentially transcribed in a Ly49-expressing cell line, EL-4. Electrophoretic mobility shift assays using oligonucleotide probes from the core Ly49i promoter and comparable regions from the Ly49a promoter demonstrated the importance of TATA-related elements in generating EL-4 and NK cell-specific DNA/protein complexes.

Cloning and characterization of a novel activating Ly49 closely related to Ly49A

The majority of the known Ly49 family members have been isolated from either C57BL/6 (B6) or BALB/c mice. Interestingly, the anti-Ly49 Ab reactivities observed in 129/J mice are different from those of B6 mice. Furthermore, immunoprecipitation of 129/J NK cell lysates with YE1/32 and YE1/48, Abs specific for the inhibitory Ly49A in B6, resulted in detection of the activation-associated DAP12 molecule. These results indicated a need for a more detailed study of this strain. Therefore, a cloning strategy was devised to isolate Ly49 cDNAs from 129/J mice. An immunoreceptor tyrosine-based inhibitory motif-containing, Ly49D-related clone was discovered that we have named Ly49O, and one immunoreceptor tyrosine-based inhibitory motif-lacking, Ly49A-related clone was discovered that we have named Ly49P. No anti-Ly49 mAb reacted with Ly49O, whereas the molecule encoded by the Ly49P cDNA was found to react with YE1/32 and YE1/48. Ly49P was found to associate with mouse DAP12, and Ab-mediated cross-linking of Ly49P resulted in mouse DAP12 phosphorylation and Ca2+ mobilization, indicating that Ly49P is a competent activation receptor. Ly49P, therefore, represents a novel member of the Ly49 activating receptor subfamily.

Cloning and Characterization of a Novel Activating Ly49 Closely Related to Ly49A

The majority of the known Ly49 family members have been isolated from either C57BL/6 (B6) or BALB/c mice. Interestingly, the anti-Ly49 Ab reactivities observed in 129/J mice are different from those of B6 mice. Furthermore, immunoprecipitation of 129/J NK cell lysates with YE1/32 and YE1/48, Abs specific for the inhibitory Ly49A in B6, resulted in detection of the activation-associated DAP12 molecule. These results indicated a need for a more detailed study of this strain. Therefore, a cloning strategy was devised to isolate Ly49 cDNAs from 129/J mice. An immunoreceptor tyrosine-based inhibitory motif-containing, Ly49D-related clone was discovered that we have named Ly49O, and one immunoreceptor tyrosine-based inhibitory motif-lacking, Ly49A-related clone was discovered that we have named Ly49P. No anti-Ly49 mAb reacted with Ly49O, whereas the molecule encoded by the Ly49P cDNA was found to react with YE1/32 and YE1/48. Ly49P was found to associate with mouse DAP12, and Ab-mediated cross-linking of Ly49P resulted in mouse DAP12 phosphorylation and Ca2+ mobilization, indicating that Ly49P is a competent activation receptor. Ly49P, therefore, represents a novel member of the Ly49 activating receptor subfamily.

Implementing a multiple-isolator unit for centralized preparation of cytotoxic drugs in a cancer center pharmacy

Due to numerous reasons: assuring safety (technicians, patients, nurses, environment), preventing medication errors, cost, maintaining pharmaceutical quality, rules and regulations, it was decided to create a dedicated room within the pharmacy for the preparation of intravenous cytotoxic drugs. After a preliminary study, the following choices were made: isolator unit instead of a vertical laminar air-flow hood, rigid surface instead of flexible film, a multiple-unit structure (one half suit unit for storage and one isolator unit for passthrough, two preparation units, each with four double-gloving portals) instead of a single-unit structure. After the equipment was installed, the physical and microbiological processes were validated and a medical/pharmaceutical catalog of protocols was created. Then the technicians were trained and the standard operating procedures were written. Updated every six months, they describe the general organization, gaseous sterilization of the isolators, the drugs and the medical devices, prescription analysis and circuit, preparation of nominative forms and labels, double checking the preparations delivery, cleaning and maintenance, documentation and reports, waste disposal, safety and protection and instructions for emergency. The pharmacists, pharmacy staff, physicians and nurses were all included in a work group responsible for the isolator unit project. The unit was opened in January 1997.

Induction of DAP12 phosphorylation, calcium mobilization, and cytokine secretion by Ly49H

The ability of several Ly49 family members to inhibit natural killer (NK) cell functions through recruitment of SHP-1 phosphatase has been reported. In contrast, the mechanisms underlying the activating signal generated by Ly49D are poorly understood. A homodimeric phosphoprotein (pp16) that physically and functionally associates with Ly49D has been described. In this study, a rabbit anti-mouse pp16 antiserum was generated and used to demonstrate that pp16 corresponds to the recently described DAP12 molecule. In addition, we show that a second Ly49 family member that lacks an immunoreceptor tyrosine-based inhibitory motif and contains a charged residue in the transmembrane domain, Ly49H, also associates with DAP12. Furthermore, we show that engagement of the Ly49H/DAP12 complex results in phosphorylation of DAP12, intracellular calcium mobilization, and tumor necrosis factor secretion in transfected cells. These results thus provide evidence that Ly49H is an activating receptor that associates with DAP12, previously described as a pp16 component of the Ly49D receptor complex.

Role of a STAT binding site in the regulation of the human perforin promoter

The pore-forming protein perforin is preferentially expressed in NK and cytotoxic T cells. To investigate the molecular regulation of human perforin gene transcription, the activity of the human perforin promoter was analyzed in human NK and T cell lines using various promoter fragments linked to a luciferase reporter gene. A core promoter was identified within 55 bp upstream of the transcription start site. This promoter region contains a guanine/cytosine box and has basal activity in YT, Kit225-k6, and Jurkat cells. A strong enhancer activity was identified between positions -1136 and -1076, a region that includes a STAT-like element. This enhancer region was active in YT cells, which have constitutive perforin expression and activated STAT3 protein, but not in Kit225-k6 or Jurkat cells, which do not have constitutive perforin expression. Mutation of the STAT binding site resulted in a dramatic down-regulation of promoter activity. Electrophoretic mobility shift assays, using a probe containing the STAT element of the perforin promoter, indicated that this element can bind STAT3 from YT cells. Moreover, the STAT element was shown to bind STAT5a/b induced by IL-2 as well as STAT1alpha induced by IL-6 in human NK cells. Together, these results suggest that STAT proteins play a key role in perforin gene transcription and provide a model by which cytokines can regulate perforin gene expression.

Role of a STAT Binding Site in the Regulation of the Human Perforin Promoter

The pore-forming protein perforin is preferentially expressed in NK and cytotoxic T cells. To investigate the molecular regulation of human perforin gene transcription, the activity of the human perforin promoter was analyzed in human NK and T cell lines using various promoter fragments linked to a luciferase reporter gene. A core promoter was identified within 55 bp upstream of the transcription start site. This promoter region contains a guanine/cytosine box and has basal activity in YT, Kit225-k6, and Jurkat cells. A strong enhancer activity was identified between positions −1136 and −1076, a region that includes a STAT-like element. This enhancer region was active in YT cells, which have constitutive perforin expression and activated STAT3 protein, but not in Kit225-k6 or Jurkat cells, which do not have constitutive perforin expression. Mutation of the STAT binding site resulted in a dramatic down-regulation of promoter activity. Electrophoretic mobility shift assays, using a probe containing the STAT element of the perforin promoter, indicated that this element can bind STAT3 from YT cells. Moreover, the STAT element was shown to bind STAT5a/b induced by IL-2 as well as STAT1α induced by IL-6 in human NK cells. Together, these results suggest that STAT proteins play a key role in perforin gene transcription and provide a model by which cytokines can regulate perforin gene expression.

DAP12-mediated signal transduction in natural killer cells. A dominant role for the Syk protein-tyrosine kinase

The murine Ly49 family contains nine genes in two subgroups: the inhibitory receptors (Ly49A, B, C, E, F, G2, and I) and the noninhibitory receptors (Ly49D and H). Unlike their inhibitory counterparts, Ly49D and H do not contain immunoreceptor tyrosine-based inhibitory motifs but associate with a recently described co-receptor, DAP12, to transmit positive signals to natural killer (NK) cells. DAP12 is also expressed in myeloid cells, but the receptors coupled to it there are unknown. Here we document the signaling pathways of the Ly49D/DAP12 complex in NK cells. We show that ligation of Ly49D results in 1) tyrosine phosphorylation of several substrates, including phospholipase Cgamma1, Cbl, and p44/p42 mitogen-activated protein kinase, and 2) calcium mobilization. Moreover, we demonstrate that although human DAP12 reportedly binds the SH2 domains of both Syk and Zap-70, ligation of Ly49D leads to activation of Syk but not Zap-70. Consistent with this observation, Ly49D/DAP12-mediated calcium mobilization is blocked by dominant negative Syk but not by catalytically inactive Zap-70. These data demonstrate the dependence of DAP12-coupled receptors on Syk and suggest that the outcome of Ly49D/DAP12 engagement will be regulated by Cbl and culminate in the activation of transcription factors.

[Analysis of hematopoietic growth factor prescriptions in 19 french cancer centers]

Medical prescription of hematopoietic growth factors (HGF) was analysed in 19 anticancer french centers during 2 months. About 4% of anticancer chemotherapeutic cycles prescribed during this period were supported by HGF prescription. The mean duration of treatment was 8 days. Among the 755 collected prescriptions, two tumor localizations represented about 50% of the prescriptions: malignant non Hodgkin lymphomas and breast cancer. The other main localizations concerned adult or pediatric soft tissue sarcomas (18%), testicular cancer (7%) and gynecologic tumors (6%). The prescription for primary prophylaxis for febrile neutropenia remains the main use of HGF (44%). The respect of the guidelines established by the F|d|ration nationale des centres de lutte contre le cancer was analyzed. Overall, 66% of the prescriptions were in adequation with these guidelines. Whereas the consommation of HGF decreased in the 19 considered institutions, it did not reach a plateau and could decrease in institutions which are awaked to the international and national recommendations.

[Treatment of discoid lupus erythematosus with sulfasalazine: 11 cases]

INTRODUCTION

Antimalaria agents and thalidomide are two reference drugs for discoid lupus erythematosus. In non-responders or after secondary resistance or contraindications, there are a number of alternative therapeutics which are less effective and more toxic. We therefore conducted an open study in patients with discoid lupus erythematosus treated with sulfasalazine.

PATIENTS AND METHODS

Seven men and four women (mean age 40 years) with severe discoid lupus erythematosus (mean duration of disease 14 years) were treated with sulfasalazine (2 g/d). This treatment was initiated after a previous failure or contraindication of antimalarial drugs or thalidomide. The acetylation phenotype was predicted in all patients with N-acetyltransferase 2 genotyping. Genome DNA was tested for mutations causing an N-acetyltransferase deficiency. Homozygous individuals or those with heterozygous composites for the tested mutations were predicted slow acetylators and those with a homozygous or heterozygous genotype for an allele carrying a normal sequence at the mutation sites were predicted rapid acetylators.

RESULTS

We had 7 complete responses, 1 partial response and 3 failures. Mean delay to efficacy was 7 weeks, longer for lesions involving the scalp (4 to 5 months). Six of the 8 responders were given sulfasalazine exclusively. The effect was suspensive and dose-dependent; the minimal effective dose was 1.5 g/d. Excepting light sensitization requiring discontinuation, there were no clinically significant side effects. Neutropenia occurred in one patient and moderate and transient live enzyme movements did not require treatment withdrawal. The only immunoallergic side effect (light sensitization) observed occurred in a slow acetylator. All responders except one were rapid acetylators.

DISCUSSION

Salazosulfapyridine, or sulfasalazine, is composed of a derivative of 5-aminosalicylic acid and a sulfamide fraction, sulfapyridine. It is only marginally used in dermatology except for psoriasis. Its efficacy in chronic lupus erythematosus has been reported in one case. We confirmed the role of this compound in the treatment of chronic lupus erythematosus. The rare observations of induced lupus and development of antinuclear antibodies are not a contraindication, but require close regular clinical and biological surveillance. The potential risk is that possible hypersensitivity could lead to reserving sulfasalazine for severe resistant chronic lupus erythematosus after failure with antimalarials and thalidomide. Nevertheless, our study demonstrates that the slow acetylator phenotype predicts immunoallergic events, as observed by other authors, and would be a factor predicting nonresponse. If these results are confirmed by other studies, it would be possible to propose sulfasalazine as a treatment for discoid lupus erythematosus in rapid acetylators.

[Perforating milia-like idiopathic calcinosis of the extremities in Down syndrome]

INTRODUCTION

Several skin diseases can be seen in patients with trisomy 21. We report a case of miliary calcinosis of the extremities.

CASE REPORT

A 15-year old adolescent with Down's syndrome presented small papular miliary lesions which had developed over 18 months and tended to discharge a chalk-like substance via the epidermis. Approximately 15 lesions were present on the hands and feet. Histologically, there was a well-delimited calcium deposit in the superficial dermis. There was no alteration in phosphorus/calcium metabolism. Brain CT-scan and cardiac echography did not reveal any calcifications.

DISCUSSION

Miliary calcinosis cutis may not be exceptional in Down's syndrome, although only 9 observations have been reported. Preferential localizations include the hands, wrists and feet. Association with syringoma has been noted but would appear to be fortuitous. Transepidermal elimination of the calcium deposits is frequent. Pathogenic hypotheses include precipitation of calcium salts in sudation products and/or increased synthesis by fibroblasts. The association with trisomy 21 appears to be significant since only three cases have been reported in patients with normal karyotypes. This entity should be individualized as perforating milia-like idiopathic calcinosis cutis of the extremities.

Characterization of an associated 16-kDa tyrosine phosphoprotein required for Ly-49D signal transduction

Ly-49D is an activating receptor on NK cells that does not become tyrosine phosphorylated upon activation. This report demonstrates that immunoprecipitation of Ly-49D, following pervanadate treatment or specific Ab cross-linking, coprecipitates a 16-kDa tyrosine-phosphorylated protein (pp16). Immunoblotting experiments and data from TCR-zeta/Fc epsilonRIgamma double knockout mice confirm that pp16 is not TCR-zeta, TCR-eta, or Fc epsilonRIgamma. Association of pp16 with Ly-49D involves a transmembrane arginine since mutation to leucine (Ly-49D[R54L]) abolishes association with pp16 in transfected P815 cells. In addition, Ly-49D(R54L) transfectants fail to mediate Ca2+ mobilization following Ab cross-linking. Therefore, signaling through Ly49D on NK cells depends on association with a distinct tyrosine phosphoprotein (pp16) in a manner analogous to that of TCR and FcR. Expression of this novel signaling peptide in both the NK and myeloid lineages indicates that pp16 is likely involved in the signal transduction cascade of additional receptor families.

Cutting Edge: Characterization of an Associated 16-kDa Tyrosine Phosphoprotein Required for Ly-49D Signal Transduction

Ly-49D is an activating receptor on NK cells that does not become tyrosine phosphorylated upon activation. This report demonstrates that immunoprecipitation of Ly-49D, following pervanadate treatment or specific Ab cross-linking, coprecipitates a 16-kDa tyrosine-phosphorylated protein (pp16). Immunoblotting experiments and data from TCR-ζ/FcεRIγ double knockout mice confirm that pp16 is not TCR-ζ, TCR-η, or FcεRIγ. Association of pp16 with Ly-49D involves a transmembrane arginine since mutation to leucine (Ly-49DR54L) abolishes association with pp16 in transfected P815 cells. In addition, Ly-49DR54L transfectants fail to mediate Ca2+ mobilization following Ab cross-linking. Therefore, signaling through Ly-49D on NK cells depends on association with a distinct tyrosine phosphoprotein (pp16) in a manner analogous to that of TCR and FcR. Expression of this novel signaling peptide in both the NK and myeloid lineages indicates that pp16 is likely involved in the signal transduction cascade of additional receptor families.