Mortality and morbidity peaks modeling: An extreme value theory approach

Hospitalizations and deaths belong to the most studied health variables in public health. Those variables are usually analyzed through mean events and trends, based on the whole dataset. However, this approach is not appropriate to comprehend health outcome peaks which are unusual events that strongly impact the health care network (e.g. overflow in hospital emergency rooms). Peaks can also be of interest in etiological research, for instance when analyzing relationships with extreme exposures (meteorological conditions, air pollution, social stress, etc.). Therefore, this paper aims at modeling health variables exclusively through the peaks, which is rarely done except over short periods. Establishing a rigorous and general methodology to identify peaks is another goal of this study. To this end, the extreme value theory appears adequate with statistical tools for selecting and modeling peaks. Selection and analysis for deaths and hospitalizations peaks using extreme value theory have not been applied in public health yet. Therefore, this study also has an exploratory goal. A declustering procedure is applied to the raw data in order to meet extreme value theory requirements. The application is done on hospitalization and death peaks for cardiovascular diseases, in the Montreal and Quebec metropolitan communities (Canada) for the period 1981–2011. The peak return levels are obtained from the modeling and can be useful in hospital management or planning future capacity needs for health care facilities, for example. This paper focuses on one class of diseases in two cities, but the methodology can be applied to any other health peaks series anywhere, as it is data driven.

[Fear of childbirth among nulliparous women: Relations with pain during delivery, post-traumatic stress symptoms, and postpartum depressive symptoms]

OBJECTIVE

Fear of childbirth is common in women who are pregnant with their first child and is associated with important consequences such as abortions and miscarriages. Twenty percent of nulliparous women seem to exhibit a mild or moderate fear, while 6% present an excessive and irrational fear known as tocophobia. Tocophobia is suggested to be associated with many negative consequences such as postpartum depression (PPD) and Post-traumatic stress (PTS). However, there is little empirical evidence to support these relationships. Recently, Fairbrother and Woody (2007) did not observe a link between the fear of childbirth and symptoms of PPD and PTS in nulliparous women. Some results, near the significance level, could be explained by a lack of statistical power. The present study focused on the link between the fear of childbirth and the process of delivery, the perception of pain, PPD and PTS. More specifically, it aimed to test three hypotheses: (i) fear of childbirth will be linked to the process of delivery, especially regarding the perception of pain, the use of anaesthesia and the use of Caesarean section; (ii) a high level of fear of childbirth will be associated with more negative postpartum consequences (namely PPD/PTS symptoms); (iii) the process of delivery and pain will also be related to post-delivery symptoms. Mediation effects were tested.

METHOD

Data from a longitudinal study were used to meet the hypotheses. A total of 176 nulliparous pregnant women responded to questionnaires at two time measurements (during pregnancy and at 5weeks postpartum).

RESULTS

Fear of childbirth is related to the perception of pain at birth among women delivering vaginally, in the absence of anaesthesia. It is also linked to symptoms of PPD and PTS, regardless of whether or not anaesthesia was used. Fear of childbirth also appears to be strongly associated to symptoms of PTS in women who have experienced an unplanned caesarean section. Thus, symptoms of postpartum PTS could play a mediating role in the link between fear of childbirth and PPD.

CONCLUSIONS

These results support the relevance of taking into account the fear of childbirth and perception of pain in connection with symptoms of PTS and PPD in nulliparous women. The unplanned caesarean section (including emergency caesarean) also appears to be important in the study of the relationship between fear and symptoms of PTS. Fear of childbirth could render the experience of childbearing more negative and predispose to PTS and PPD. Enabling psychological vulnerabilities could also be an interesting avenue for understanding these links. Limitations are discussed.

The systemic control of circadian gene expression

The mammalian circadian timing system consists of a central pacemaker in the brain's suprachiasmatic nucleus (SCN) and subsidiary oscillators in nearly all body cells. The SCN clock, which is adjusted to geophysical time by the photoperiod, synchronizes peripheral clocks through a wide variety of systemic cues. The latter include signals depending on feeding cycles, glucocorticoid hormones, rhythmic blood-borne signals eliciting daily changes in actin dynamics and serum response factor (SRF) activity, and sensors of body temperature rhythms, such as heat shock transcription factors and the cold-inducible RNA-binding protein CIRP. To study these systemic signalling pathways, we designed and engineered a novel, highly photosensitive apparatus, dubbed RT-Biolumicorder. This device enables us to record circadian luciferase reporter gene expression in the liver and other organs of freely moving mice over months in real time. Owing to the multitude of systemic signalling pathway involved in the phase resetting of peripheral clocks the disruption of any particular one has only minor effects on the steady state phase of circadian gene expression in organs such as the liver. Nonetheless, the implication of specific pathways in the synchronization of clock gene expression can readily be assessed by monitoring the phase-shifting kinetics using the RT-Biolumicorder.

Secular trends of hip fractures in Québec, Canada

This study examined the secular trends of hip fracture incidence among individuals 50 years and older in Québec between 1993 and 2004. Age-standardized rates decreased at both the provincial and regional levels. The largest relative decrease was observed among younger females, and rates declined more slowly in the elderly.

INTRODUCTION

The population of the province of Québec is among the oldest in North America. Before the trend rupture reported in the late 1990s in several countries, hip fracture (HF) incidence rates did not show a secular trend (between 1981 and 1992). This study examined the secular trends of HF incidence at the provincial level and in two of the most important urban areas of the province, Montréal and Québec City, between 1993 and 2004.

METHODS

All hospitalisations of individuals 50 years and older living in the province of Québec between 1993 and 2004 with a main diagnosis of HF were included. Standardized rates of HF incidence were calculated for females and males, 50-74 years and 75 years and older.

RESULTS

The Québec City area showed a strong decreasing trend in HF rates for younger females, but the other groups did not show an obvious trend. Although our models did not support the existence of significant differences in trends between both areas, the rates of HF of younger males and, to a lesser extent, of older women in the Montréal area were significantly higher than in the Québec City area.

CONCLUSIONS

Differences observed in hip fracture rates as well as in secular trends between age groups and gender emphasise the need for decision makers to rely on results based on age-specific and sex-specific analyses.

Echinoderms as bioindicators, bioassays, and impact assessment tools of sediment-associated metals and PCBs in the North Sea

The study assessed the occurrence, possible toxicity, and impact of sediment-associated metals and PCBs in the coastal zone of the southern North Sea using echinoderms as representatives of the macrobenthos. Metals and PCBs were analyzed in the sediments and in the body compartments of the starfish Asterias rubens from 11 stations. The general toxicity of sediment-associated contaminants was assessed by bioassays using embryonic and larval developments of both A. rubens and the sea urchin Psammechinus miliaris. The impact of contamination was assessed by measuring cellular immune responses of A. rubens collected in the same stations. Contamination of the starfish by metals and PCBs closely reflected that of the sediments. However, bioaccumulation was element-specific for metals and depended on the chlorination pattern for PCBs. The sediment-associated contaminants appeared to be toxic in both the A. rubens and P. miliaris developmental assays. Moreover, metals were shown to affect the immune responses of starfishes living in contaminated stations. The most significant effects on biological responses were recorded in the plumes of the Scheldt/Rhine/North Sea Canal and the Elbe/Weser Rivers.

[Etiological factors of generalized anxiety disorder]

Generalized Anxiety disorder (GAD) is a widespread psychiatric syndrome involving significant consequences on people's health. However, recent data show that this disorder has received little attention when compared to other anxiety disorders. A review of the publication on GAD also stated that the majority of research has been conducted on descriptive issues, whereas etiological factors received lower rates of publication. This may be explained by the fact that changes in the conceptualization of GAD slowed down the progression of researches focussing on the identification of factors implicated in the development and the maintenance of its symptoms. For example, in the third version of the Diagnostic and Statistical Manual of Mental disorders (DSM) published in 1980, GAD could only be assigned if patients had a persistent anxiety without reporting specific symptoms of other anxiety disorders (eg Specific Phobias, Panic Disorder, Obsessive-Compulsive Disorder). With DSM III-R and DSM IV, excessive worry became the central feature of GAD, which increased its diagnostic validity. Taking that into account, where do we stand in the comprehension of GAD? What are the etiological factors identified as playing a role in the development and the maintenance of GAD and its central feature, excessive and uncontrollable worry? The goal of this article consists to provide answers to these questions by reviewing the literature of the current knowledge of GAD and examining various theories and explanatory models available. Firstly, many studies suggest that environmental factors are implicated in the development and maintenance of GAD. However, the majority of researches rests on an out-of-date conceptualization of GAD. Furthermore, the nature of experimental designs used in researches limits their conclusion. The first environmental factor documented is negative life events. Researchers noted that the occurrence of one or more negative life events being significant and appearing in an unexpected way was associa-ted with an increase in the risk to develop a GAD (eg. Familial problems (eg conflicts, abuses), considered as chronic stress-inducing situations, have also been suggested as etiological factor of GAD. Among the other environmental factors identified are separation during childhood, role inversion during childhood, lack of social interactions, poor life satisfaction, and modeling of a relative having an anxiety disorder. The cognitive and behavioral approach has been widely used during the last two decades to precise the etiology of GAD. First of all, some studies have pointed out the function of worry, which is to suppress images associated with negative thoughts (eg. Thus, GAD patients seem to develop excessive worries in order to prevent more negative feeling associated with the images of a thought. Other authors suggested that a deficit of attention might be responsible of excessive worry. Finally, some cognitive variables such as intolerance of uncertainty, false beliefs about worry, negative problem orientation and cognitive avoidance have been suggested as playing a determinant role in the development and maintenance of GAD. In order to resume the empirical findings available in the literature, an etiological model gathering the cognitive, behavioral, and environmental factors implicated in GAD is proposed. This model suggests that GAD is the result of a psychological vulnerability activated by a tension resulting from a negative event. Finally, recommendations are brought concerning future researches on GAD and its central characteristic, excessive and uncontrollable worry.

[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.

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.

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.

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.

Differential tyrosine phosphorylation of inhibitory versus activating Ly-49 receptor proteins and their recruitment of SHP-1 phosphatase

Killer cell inhibitory receptors represent a family of p58/70-Ig-like proteins expressed on the surface of human NK cells. Engagement of class I MHC by killer cell inhibitory receptors turns off the lytic machinery of NK cells. This receptor/ligand interaction results in phosphorylation of intracellular tyrosine residues of p58/70 proteins. Murine NK cells express surface receptors of an unrelated family of type II lectin-like proteins, Ly-49, that have similar functions. Ly-49A, -C, and -G2 represent murine inhibitory receptors. However, Ly-49D functions as an activation receptor on the surface of NK cells. This dichotomy of function between Ly-49 family members suggested different signaling events upon receptor/ligand interaction. Here we demonstrate that: 1) in transfected Cos7 and murine NK cells, Ly-49A, -C, and -G2 are phosphorylated following pervanadate stimulation, whereas Ly-49D is not; 2) mAb-induced receptor ligation mediates tyrosine phosphorylation of Ly-49A and -G2, but not Ly-49D; 3) SHP-1 coprecipitates with Ly-49A and -G2 following receptor phosphorylation; and 4) tyrosine phosphorylation of Ly-49 inhibitory receptors depends on tyrosine residues restricted to the immunoreceptor tyrosine-based inhibitory motif. Our data further support the involvement of immunoreceptor tyrosine-based inhibitory motifs as crucial sequences regulating receptor-mediated inhibitory functions in NK cells.

Differential tyrosine phosphorylation of inhibitory versus activating Ly-49 receptor proteins and their recruitment of SHP-1 phosphatase

Killer cell inhibitory receptors represent a family of p58/70-Ig-like proteins expressed on the surface of human NK cells. Engagement of class I MHC by killer cell inhibitory receptors turns off the lytic machinery of NK cells. This receptor/ligand interaction results in phosphorylation of intracellular tyrosine residues of p58/70 proteins. Murine NK cells express surface receptors of an unrelated family of type II lectin-like proteins, Ly-49, that have similar functions. Ly-49A, -C, and -G2 represent murine inhibitory receptors. However, Ly-49D functions as an activation receptor on the surface of NK cells. This dichotomy of function between Ly-49 family members suggested different signaling events upon receptor/ligand interaction. Here we demonstrate that: 1) in transfected Cos7 and murine NK cells, Ly-49A, -C, and -G2 are phosphorylated following pervanadate stimulation, whereas Ly-49D is not; 2) mAb-induced receptor ligation mediates tyrosine phosphorylation of Ly-49A and -G2, but not Ly-49D; 3) SHP-1 coprecipitates with Ly-49A and -G2 following receptor phosphorylation; and 4) tyrosine phosphorylation of Ly-49 inhibitory receptors depends on tyrosine residues restricted to the immunoreceptor tyrosine-based inhibitory motif. Our data further support the involvement of immunoreceptor tyrosine-based inhibitory motifs as crucial sequences regulating receptor-mediated inhibitory functions in NK cells.

The diagnostic value of urinary Crosslaps and serum alkaline phosphatase in patients with prostate cancer

OBJECTIVE

To determine whether the urinary excretion of Crosslaps and serum alkaline phosphatase (ALP) are useful bone markers in patients with prostate cancer.

PATIENTS AND METHODS

The study included 112 patients, comprising 25 with benign prostatic hyperplasia and 87 with carcinoma of the prostate, 41 of whom had localized prostate cancer and 46 with bone metastases. In the last group, 16 were stable and 30 were in clinical progression. Prostate-specific antigen (PSA) and the bone markers serum bone ALP and urinary Crosslaps were determined on the same day.

RESULTS

The rates of excretion of Crosslaps were significantly greater in patients with than in those without bone metastases. Only Crosslaps showed a significant difference between patients with stabilized metastatic disease and those with no bone involvement. Crosslaps had a higher specificity and positive predictive value than had PSA level in patients with bone metastases, and a higher sensitivity than bone ALP.

CONCLUSION

These preliminary findings suggest that Crosslaps may be useful as an additional bone marker in patients with prostate cancer and may provide information of the metastatic spread to bone in these patients. Prospective studies with serial measurements of bone markers are currently underway to relate these results to the progression of disease and to evaluate the response to treatment of bone metastases.

Multicentric evaluation of the MDR phenotype in leukemia. French Network of the Drug Resistance Intergroup, and Drug Resistance Network of Assistance Publique-Hôpitaux de Paris

The wide discrepancies in the frequency of 'positive' samples for multidrug resistance (MDR) phenotype within the same type of tumor observed in the literature justified the need for the definition of consensus recommendations. To define standard techniques of MDR phenotype measurement, we ran a large multicentric evaluation of the different methods available. Thirty-six French centers participated in the study, and 742 samples of 2-10 x 10(6) viable cells were sent by overnight express mail between December 1993 and February 1996. The same batches of MRK16, 4E3 and UIC2 were used. Nineteen samples of leukemia (12 AML, 1 ALL, 6 lymphoproliferative syndromes) and six leukemic cell lines with different levels of MDR expression were tested. Five meetings reached agreement concerning the guidelines for each technique, except immunocytochemistry. The 19 fresh samples were tested by each center using one to four techniques among cytofluorometry, immunocytochemistry, functional tests and RT-PCR. Five samples were diagnosed as 'negative' according to local criteria, with few discordant results (0 to 16% of 'positive' results). For all the 14 remaining samples, large discrepancies were observed from center to center, and from one technique to another. No correlations could be found between techniques. Flow cytometric analysis of cells already exposed to MRK16 or control IgG2A, fixed in paraformaldehyde and sent to centers did not reduce the discrepancies between centers in two of the four samples with moderate expression, emphasizing the role of histogram interpretation. The use of alternative monoclonal antibodies (4E3 and UIC2) did not reduce the discrepancies observed. In a second step, the K562 parental cell line, a low resistant subline (K562/HHT100, x7 resistance index to DNR) and a high resistant subline (K562/HHT300, x125 resistance index to DNR) were sent blindly three times, with an increasing level of recommendations for flow cytometry. Dramatic improvements were observed in cytometric results when the result was expressed as the ratio of arithmetic mean of fluorescence of antibody (10 microg of MRK16)/arithmetic mean of fluorescence of control (10 microg IgG2A): the proportion of expected results increased from 61 to 100% for K562, and from 37 to 85% for K562/HHT100. For uptake and drug efflux measurements, the use of 1 h uptake of 0.1 microM of rhodamine, followed by 1 h efflux +/-10 microM of verapamil, permitted an increased reproducibility of the technique from 71 to 100% for K562 and K562/HHT100. Whatever the technique used, concordant results were obtained for K562/HHT300. The immunocytochemistry, using several antibodies (MRK16, JSB1 and C219) gave many non-interpretable results (44%), due to a frequent high background and discordant results between antibodies in the same centers, and discordant conclusions between centers. The group does not recommend this technique for circulating tumoral cells.

The NK2.1 receptor is encoded by Ly-49C and its expression is regulated by MHC class I alleles

A dual receptor system composed of activation and inhibitory receptors apparently controls NK cell-mediated lysis. In the C57BL/6 mouse, the NK1.1 molecule acts as an activation receptor whereas Ly-49A, C and G2 can inhibit NK cell lysis of target cells expressing specific MHC class I molecules. We previously reported that NK2.1 is an activation receptor sharing structural properties with members of the NKR-P1 and Ly-49 receptor families. In this study, we have shown that NK2.1 is encoded by the previously described Ly-49C gene. We also found that the expression level of NK2.1/Ly-49C is modulated by H-2-dependent factors and that this regulation differs from that previously described for Ly-49A. Flow cytometry analyses of NK-enriched spleen cells from MHC congenic strains on C57BL/10 and BALB/c backgrounds indeed revealed that the level of NK2.1/Ly-49C expression, but not the number of positive cells, is low in strains expressing H-2b and H-2k haplotypes as compared to H-2d mice. Similar analyses of splenic NK cells from two series of congenic and congenic recombinant strains on the C57BL/10 background indicate that the main regulatory element(s) are most likely the H-2Kb and H-2Dk alleles. Together with our and others previous observations, these results identify the NK2.1/Ly-49C antigen as a receptor for MHC class I molecules whose expression is regulated by host MHC genes.

Selective inhibition of human and mouse natural killer tumor recognition using retroviral antisense in primary natural killer cells: involvement with MHC class I killer cell inhibitory receptors

The natural killer tumor recognition (NK-TR) protein has been shown to be a necessary component for the killing of NK-sensitive and virus-infected targets by the rat RNK-16 cell line. Class I-recognizing killer cell inhibitory receptors (KIR) have been found in the human (p58; NKAT family) and mouse (Ly-49 family). The principal functional characteristic of these receptors is their ability to block NK cell lysis by recognition of selected class I molecules on target cells. In the present study, we examined whether abrogation of NK-TR expression by retroviral infection of primary human or mouse NK cells with virus-producing antisense NK-TR also would demonstrate loss of non-MHC-restricted killing and whether the NK-TR was associated with KIR function in humans or with Ly-49 in the mouse. Using short term culture of fresh human or mouse NK cells, antisense NK-TR-treated NK cells demonstrated strong selective reduction of NK cytotoxicity. NK-TR was necessary for lytic activity even when KIR function was blocked by Ab in experiments involving NK3.3 lysis of HLA.cw3-expressing targets or killing of Dd targets by Ly-49A+ or Ly-49G2+ mouse NK cells. These studies extend our previous studies in rat NK cell lines to demonstrate that primary mouse and human NK cells require NK-TR for non-MHC-restricted lysis of tumor and virus-infected targets. In addition, the reversal of KIR or Ly-49 inhibition of NK cell lysis requires NK-TR expression for cellular killing in both human and mouse.

[Intrapancreatic accessory spleen. X-ray computed tomographic and MRI imaging]

We report MRI and CT findings of an intrapancreatic accessory spleen. The lesion was hypervascular on CT and isointense to the spleen on MRI. This uncommon localisation may simulate a pancreatic mass. If the diagnosis is suspected, it can be confirmed by scintigraphy.

Selective inhibition of human and mouse natural killer tumor recognition using retroviral antisense in primary natural killer cells: involvement with MHC class I killer cell inhibitory receptors

The natural killer tumor recognition (NK-TR) protein has been shown to be a necessary component for the killing of NK-sensitive and virus-infected targets by the rat RNK-16 cell line. Class I-recognizing killer cell inhibitory receptors (KIR) have been found in the human (p58; NKAT family) and mouse (Ly-49 family). The principal functional characteristic of these receptors is their ability to block NK cell lysis by recognition of selected class I molecules on target cells. In the present study, we examined whether abrogation of NK-TR expression by retroviral infection of primary human or mouse NK cells with virus-producing antisense NK-TR also would demonstrate loss of non-MHC-restricted killing and whether the NK-TR was associated with KIR function in humans or with Ly-49 in the mouse. Using short term culture of fresh human or mouse NK cells, antisense NK-TR-treated NK cells demonstrated strong selective reduction of NK cytotoxicity. NK-TR was necessary for lytic activity even when KIR function was blocked by Ab in experiments involving NK3.3 lysis of HLA.cw3-expressing targets or killing of Dd targets by Ly-49A+ or Ly-49G2+ mouse NK cells. These studies extend our previous studies in rat NK cell lines to demonstrate that primary mouse and human NK cells require NK-TR for non-MHC-restricted lysis of tumor and virus-infected targets. In addition, the reversal of KIR or Ly-49 inhibition of NK cell lysis requires NK-TR expression for cellular killing in both human and mouse.

[Dietary treatment of mild to moderate hypercholesterolemia. Effectiveness of different interventions]

OBJECTIVE

To compare the efficacy of brief dietary intervention by family physicians in their daily practice and in group sessions to standard dietetic treatment in mild to moderate hypercholesterolemia.

DESIGN

Randomised clinical trial.

SETTING

Family practice clinic in a remote community.

PARTICIPANTS

Between September 1, 1991 and September 30, 1992, 135 men and women between 20 and 60 years old with mild to moderate hypercholesterolemia were recruited and randomly assigned to three treatment groups to be taught the American Heart Association low fat diet. Each participant had an LDL-C reading higher than the desirable level set by the Canadian Consensus Conference on Cholesterol.

INTERVENTIONS

The three treatment groups received different interventions: individual consultations with a family physician in his office (phase I); group sessions with a physician and a dietician (phase II); and individual consultations with a dietician (phase II). Participants were followed for 6 months with visits and blood tests every 2 months.

MAIN OUTCOME MEASURES

Reduction in serum levels of total cholesterol, LDL-C, HDL-C, and triglycerides was measured after 2, 4, and 6 months of dietary treatment. Changes in risk factors (smoking, weight, level of physical activity) and patients' cholesterol/saturated fat index were also measured.

RESULTS

Ninety-nine subjects completed the 6-month regimen. The mean reduction in serum LDL-C was 0.08 mmol/L (1.8%) in Group I, 0.07 mmol/L (1.6%) in Group II, and 0.28 mmol/L (6.3%) in Group III (P = 0.94). An LDL-C reduction of 10% or more relative to initial level was observed in 27% of participants in Group I and approximately 40% of subjects in the other two groups (P = 0.41). Counseling resulted in a decrease in body weight, smoking, and dietary fat consumption and an increase in physical activity.

CONCLUSIONS

Treatment by a dietician achieved better results and should remain the standard. Physicians should focus on the detection and control of other heart disease risk factors.

Eye movement desensitization and reprocessing in the treatment of test anxiety: a study of the effects of expectancy and eye movement

Eye Movement Desensitization and Reprocessing (EMDR) is a recently invented technique acclaimed as a major breakthrough for a range of anxiety-related symptoms. To determine the importance of the eye movement and expectancy variables, we conducted a one-hour session with 41 undergraduate subjects (11 males and 30 females) with test anxiety. A 2 (eye movement vs no eye movement) x 2 (high expectancy vs low expectancy) analysis of variance was performed on three dependent measures: (1) Subjective Units of Disturbance Scale (SUDs). (Wolpe, The Practice of Behavior Therapy, 1982); (2) Validity of Cognition Scale (VOC) (Shapiro, 1992); and (3) the Test Anxiety Inventory (TAI) (Spielberger, TestAnxiety Inventory Preliminary Professional Manual, 1977). The data indicate that all subjects, regardless of treatment condition, showed a significant decrease in anxiety on the TAI. Subjects in the eye-movement condition reported feeling less anxious (SUDs) than those in the no-eye-movement condition. We found no significant main effect or interactions for any of the dependent measures for expectancy.

[Decoding facial emotional prototypes]

This study examined the recognition of the facial prototypes comprised in the expressive emotional repertory proposed by Ekman and Friesen (1978a) and by Wiggers (1982). The prototypes were shown to 74 decoders who had to rate the intensity of the emotion or emotions being portrayed. The results indicated that the majority of the prototypes, except those of fear and disgust, clearly signaled the predicted emotion. The various prototypes related to the same emotion were found to differ in their signal value, some of them being better recognized and more specific than others. Some prototypes of fear and disgust were found to signal mixed rather than pure emotions. The results also revealed that the level of recognition of emotional expression varies according to the encoder which suggests that interindividual differences in facial anatomy influence the perception of emotion.

Components and recognition of facial expression in the communication of emotion by actors

This article addresses the issue of the communication of emotion by actors. In Study 1, the facial behavior of 6 actors portraying emotions as felt or unfelt were analyzed with the Facial Action Coding System. Results indicated that the portrayals of felt emotions were closer to the expression of genuine emotion than the portrayals of unfelt emotions for 3 of the 6 emotions under investigation. Study 2 examined the decoding of actors' portrayals from facial behavior. Decoders were found to be very accurate in recognizing the emotional category but not in judging the encoding condition.

Components and recognition of facial expression in the communication of emotion by actors

This article addresses the issue of the communication of emotion by actors. In Study 1, the facial behavior of 6 actors portraying emotions as felt or unfelt were analyzed with the Facial Action Coding System. Results indicated that the portrayals of felt emotions were closer to the expression of genuine emotion than the portrayals of unfelt emotions for 3 of the 6 emotions under investigation. Study 2 examined the decoding of actors' portrayals from facial behavior. Decoders were found to be very accurate in recognizing the emotional category but not in judging the encoding condition.

Two distinct protein isoforms are encoded by ntk, a csk-related tyrosine protein kinase gene

Recently, we and others have cloned cDNAs encoding a second member of the Csk family of inhibitory tyrosine protein kinases, which we have termed Ntk. Intriguingly, the mouse ntk cDNA sequences published by two independent groups differed by the presence or absence of a 136 nucleotide-insert near their 5' ends. In this report, we demonstrate that this 136 nucleotide-sequence likely corresponds to a complete exon in the ntk gene (termed exon 2), and that the two types of cDNAs/transcripts are produced by alternative splicing. Using ribonuclease protection assays, it was also established that brain and lymphoid organs, as well as most hemopoietic cells, predominantly expressed ntk transcripts lacking exon 2. In contrast, selected hemopoietic cell lines, such as the immature myeloid cell lines 32D cl3(G) and WEHI-3B, exclusively possessed exon 2-bearing RNAs. Interestingly, exon 2 introduced a novel in-frame upstream AUG in the ntk transcript, which is in the appropriate context for translation initiation. Evidence was obtained that this AUG is utilized in vivo, and that it extends the amino-terminal sequence of Ntk by 40 amino acids. Indeed, while exon 2-deficient ntk RNAs were translated into a 52 kilodalton (kDa) polypeptide (p52ntk), those bearing exon 2 produced a 56 kDa protein (p56ntk). Furthermore, p56ntk, but not p52ntk, was recognized by an antiserum directed against the novel amino-terminal sequence encoded by exon 2. Additional biochemical characterizations showed that p52ntk and p56ntk were localized to the cytoplasm, and that they partially accumulated in the detergent-insoluble cellular fraction. This last finding suggested that the Ntk proteins can associate with the cytoskeleton. Finally, through linkage analysis of two multilocus crosses, the ntk gene was mapped to Chromosome 10 in the mouse. Taken together, these data showed that ntk, a csk-related tyrosine protein kinase gene, encodes two protein isoforms expressed in distinct cell types. Moreover, they raised the possibility that Ntk may be involved in the regulation of Src-like enzymes in detergent-insoluble cellular compartments.

Polymerase chain reaction using arbitrary primer for the design and construction of a DNA probe specific for Porphyromonas gingivalis

In this work, we used a novel approach for the design and construction of DNA probes which requires no knowledge of target DNA sequence. We demonstrated that species-specific genetic markers, identified as such among monomorphic, randomly amplified DNA segments generated by the polymerase chain reaction with arbitrary primer can be labelled to yield so-called "anonymous probes". We report here on the construction of such an anonymous probe, 1146 bp long, specific for the Gram-negative anaerobe Porphyromonas gingivalis, a suspected major etiologic agent of chronic periodontitis in adults.

[Lymphocyte hybridization and cancerology: diagnostic and therapeutic applications. Example of tumor markers]

First described in 1975 by Köhler and Milstein, monoclonal antibodies (Mabs) result from the fusion of a B lymphocyte and a myeloma cell. Among the many uses of Mabs, oncology constitute a privileged, but difficult, field of investigation: the antigen heterogeneity and difficulty of access to tumors are major obstacles. In diagnosis, the Mabs allow the identification and the quantification of tumor specific or tumor-associated antigens: the assay of circulating tumor markers is one of the largest applications. In situ localization of tumors is also possible, using radiolabelled Mabs. In therapeutics, Mabs are used alone or linked to radionuclides, toxins, anticancer drugs or enzymes. Ex vivo treatment of bone marrow is used in autologous and allergenic grafts. The use of mono (Fab,Fv) or bivalents (F(ab)'2) antibody fragments, chimeric or human Mabs, cocktails of Mabs, intended to improve sensitivity and specificity of the tests, are the main prospects of this research area.

The murine NK2.1 antigen: a 130 kD glycoprotein dimer expressed by a natural killer cell subset of the spleen, thymus and lymph nodes

Murine natural killer (NK) cells express a few antigens not found on other leukocyte subsets. The NK1.1 antigen, that is present in only a few mouse strains, has been extensively characterized whereas our knowledge of the NK2.1 antigen, which is more commonly expressed, remains, as yet, limited. Our laboratory has previously reported the production of a mAb (4LO3311) recognizing a murine NK cell-specific molecule with a similar strain distribution as the NK2.1 antigen formerly defined with an NZB anti-BALB/c antiserum. In this study, we demonstrate by sequential immunoprecipitation that 4LO3311 represents the first NK2.1 antigen-specific mAb. This reagent was used to immunoprecipitate the NK2.1 antigen from 125I-labeled lysates of fresh NK-enriched spleen cells. SDS-PAGE analyses revealed that the NK2.1 antigen is expressed at the cell surface as a N-glycosylated disulfide-linked protein dimer with approximately 65 kD subunits. The NK2.1 antigen is likely to be anchored in the plasma membrane by a peptide moiety since its expression on NK cells was not affected by treatment with phosphatidylinositol-specific phospholipase C. In addition to be present on a splenic NK cell subset, the NK2.1 antigen is shown to be expressed by a small number of CD4-CD8-thymocytes and by a subset of CD4-CD8-IgG- lymph node cells. Finally, it is shown here that unlike the NKR-P1, the rat homologue of the murine NK1.1 antigen, neither the NK2.1 nor the NK1.1 antigen is expressed by polymorphonuclear leukocytes.