Navigation-guided neuroendoscopic removal of an intracranial migratory pellet from the thalamus of a 4-year-old girl.

Extraction of a bullet fragment seated in deep brain parenchyma utilizing a neuroendoscope has not been previously reported in the literature. The authors report the case of a 4-year-old patient who presented after a pellet gun injury with a projectile located 6 cm intracranially and lodged within the posterior thalamus and near the posterior limb of the internal capsule. Initial operative repair included repair of a CSF leak with duraplasty, minimal brain debridement, and elevation of a depressed skull fracture. Subsequent CT at 2 months postoperatively revealed migration of the deep intracranial pellet. This finding correlated with intermittent worsening neurological symptoms and signs. A rigid 3-mm neuroendoscope with CT stereotactic navigation was then used to remove the pellet fragment from the thalamus. The patient returned home with alleviation of clinical symptoms and an uneventful postoperative recovery. This case demonstrates that navigation-guided neuroendoscopy can be successfully used to remove projectile fragments from deep brain structures, especially when the migration is along the initial path of the bullet. This technique represents another low-risk curative option in the management of retained bullet fragments in gunshot wound injuries to the head.

[Suicidal risk prevention in schizophrenia: Importance of family psychoeducation]. / Prévention du risque suicidaire dans la schizophrénie : importance de la psychoéducation des familles.

OBJECTIVES: Although mortality by suicide in schizophrenia seems to have decreased in some countries over the last 30 years, it remains much higher than in the general population. Studies have shown this risk to impact around 5% of patients, corresponding to a risk almost 2.5 times higher than in the general population. Family psychoeducation in schizophrenia has been demonstrated to lead to symptom reductions and to an improvement of the quality of life, two factors that should contribute to decreasing the suicidal risk. Therefore, if families attend an efficient psychoeducation program, we can expect a decrease in the patient suicidal risk. Attending a family psychoeducation program at the beginning of the disease would also be associated with a stronger preventive effect on suicidal mortality. The objective of this study is to describe the suicide attempt rate of patients who suffer from schizophrenia before and one year after one of their relatives participated to the family psychoeducation program Profamille. METHOD: We performed a retrospective study on 1209 people who attended the Profamille (V3.2 version) Family Psychoeducation Program. This program has 2 modules: an initial training module of 14 weekly or fortnightly sessions, and a consolidation module of 4 sessions over 2 years. Sessions last 4 hours and follow a precise and structured course. Data were collected from 40 different centers in France, Belgium and Switzerland and were based on participants assessed at the beginning and one year after the first module. Self-assessment from the relatives participating in the program provided the measure of patients' suicide attempts. An assessment at T0 explored the attempts over the 12 months before the beginning of the program while the assessment at T1 analyzed those during the 12 months following the end of the Program. The Chi2 test was used to compare the suicide attempt rates for each period, using a significance threshold of 0.05. Since the risk of suicide is greater in the first years of the illness, rates of attempts are also calculated according to the age of disorder. The analysis was carried out with the statistical software R. RESULTS: The number of participants reporting that their relative had attempted suicide in the previous 12 months decreased from 41 to 21. The annual attempts rate was evaluated at 6.4 % before the Profamille program and decreased to 2.4 % a year after the end of the program (P=0.0003). The reduction of the attempt rate was observed even for patients with schizophrenia for more than 10 years. CONCLUSION: This study shows the positive impact of Profamille on reducing the rate of suicide attempts in patients with schizophrenia. It has been shown that the risk is highest at the beginning of the disorder. Therefore, based on our results, it would seem appropriate to propose the Profamille program at an early stage.

[Depression in relatives of patients with schizophrenia: 8-month longitudinal outcome of ProFamille Program]. / La dépression chez les proches de patients souffrant de schizophrénie : effets longitudinaux sur 8 mois du programme ProFamille.

INTRODUCTION: Mental illness such as schizophrenia is a major public health concern. In France, the economic cost of schizophrenia represents 2% of total medical expenditures. Schizophrenia has an impact on health and quality of life not only for patients but also for relatives. Family psychoeducation is a complementary therapeutic intervention to ordinary clinical care deigned to alleviate the burden of care among relatives of patients with schizophrenia. Literature suggests such programs including the patients' family members reduce the risk of relapse. Current studies also suggest that negative emotions expressed by family members have negative consequences on patients' mental health and need to be addressed. However, family psychoeducation is still underdeveloped in France. The objective of this study was to assess the longitudinal outcome on depression level of a psychoeducation program for relatives of schizophrenic patients. The program was held in Paris and Région Île-de-France "Cluster ProFramille Île-de-France" between 2012 and 2014. METHODS: Level of participant's depression was assessed by the Center for Epidemiologic Studies - Depression Scale (CES-D). Measures of depression were made for four time points: 2 months before joining the program (T1), at the beginning of the program (T2), at midpoint of the first program module (3 months, T3) and at the end of the first program module (6 months, T4). Repeated-measures ANOVA were performed to assess longitudinal change in a participant's level of depression. Type of coping strategies, knowledge about the disease, dominant thoughts and emotional progress are assessed by the program. Univariate correlation with CES-D differences between T1 and T4 were assessed. Variables with a significant association were included in a multivariate linear model to explain CES-D difference. RESULTS: Sixty-five relatives participated to the "Cluster ProFramille Île-de-France" between 2012 and 2014 and terminated with the first module of the program. Repeated-measures ANOVA on CES-D scores between T1 and T4 (8 months) showed a significant decrease in average scores for all participants. The mean of decrease was 7 points, equivalent to a 26.6% pre-post decrease level of depression. Significant univariate correlations with depression decrease over 8 months were with "psychomotor tiredness", "frequent worries" and "dealing with worries". Multivariate linear regression only confirmed the significant role of diminishing fatigue in relation to the decrease of depression. CONCLUSION: Our study's results showed that the ProFamille program was efficient in reducing the level of depression for its participants over an 8 month period. As the participants progressed on managing their fatigue, their depressed moods improved.

[Assessment of mental states at risk of psychotic transition: validation of the French version of the CAARMS]. / Évaluation des états mentaux à risque de transition psychotique: validation de la version française de la CAARMS.

This article aims to present the validation study of the French version of the Comprehensive Assessment of at risk mental states (CAARMS), an interview that seeks to determine whether young adults criteria for at-risk (AR) mental states, or psychosis. We assessed 40 young subjects, 15 were considered as "prodromal" (Prd) and 10 as experiencing a first episode of psychosis (PEP) by our expert clinician at the center - centre d'évaluation des jeunes adultes et adolescents, University Hospital Centre, Paris - and 15 were healthy controls matched for age and sex. When assessed with the CAARMS, 73 % (n=11) of the prodromal subjects reached the criteria for AR mental state, four subjects did not reach the criteria for AR, nor psychosis (P) and 100 % of the PEP reached the criteria for P. The three groups were significantly different on CAARMS total score (P<0.001) and subscores ; Prd subjects had intermediate scores between PEP (P<0.001) and controls (P<0.001) scores, PEP showing the highest scores. Post-hoc analysis showed that Prd significantly differed from Controls on each subscale (P<0.001) and that Prd differed from PEP on the "positive symptoms" subscale (P<0.001), as well as on "behavioural change" (P=0.021), owing to difference on the item "impaired role function". We used the brief psychiatric rating scale 24 items with anchor (BPRS24-EA) in addition to with the CAARMS, the AR group showed intermediate scores between controls and P subjects. Total scores of both scales were correlated (r=0.408 ; P=0.043) and the BPRS24-EA "positive symptoms" score was correlated with CAARMS' scores on the "Positive symptoms" subscale (r=0.456, P=0.022), "emotional disturbance" (r=0.506, P=0.01), and "behavioural change" (r=0.666 P=0.001). We found no correlation between BPRS negative and depression subscales and any of the CAARMS' subscales. When looking at its reliability, reliability coefficients (Cronbach's alpha) showed excellent reliability for "positive symptoms", "emotional disturbance", "behavioural change" and "general psychopathology" (respectively r=0.82, 0.75, 0.78, 0.84, 0.83) and moderate reliability for "cognitive change", "negative symptoms" and "motor/physical change" (respectively r=0.39, 0.59, 0.43). Overall, analysis of the results of construct validity, concurrent validity and reliability of the CAARMS indicates that the French version is valid and reliable. It is now available to develop and implement early detection programs in French speaking countries.

Community trial of insecticide-treated bed net use promotion in southern Ghana: the Net Use Intervention study.

Insecticide-treated nets (ITNs) reduce malaria transmission and related morbidity and child mortality; however, incorrect and inconsistent use limits their protective factors. This community trial titled the Net Use Intervention study sought to bridge the gap between ITN ownership and use in southern (coastal) Ghana and to determine the best mix of communication tools to affect behavior of ITN owners to consistent use while maintaining optimal internal and external validity. This two-group, non-randomized experiment evaluated a multichannel, multisector intervention process over the course of 8 weeks. A longitudinal cohort was scientifically sampled from six intervention and six control communities for both baseline and posttest surveys. The posttest survey showed no change in knowledge of ITNs in the intervention or control. In terms of use the previous night, there was a strong and statistically significant intervention effect (OR = 1.67; p < .05) within the intervention communities. The overall increase in ITN coverage was approximately one person per night per every two households. The promotion efforts succeeded well beyond the planners' expectations, not only promoting usage but also dramatically increasing demand for new ITNs.

Effect of botulinum toxin injection on nocturnal bruxism: a randomized controlled trial.

OBJECTIVE: To evaluate the effect of botulinum toxin type A on nocturnal bruxism. DESIGN: Twelve subjects reporting nocturnal bruxism were recruited for a double-blind, randomized clinical trial. Six bruxers were injected with botulinum toxin in both masseters, and six with saline. Nocturnal electromyographic activity was recorded in the subject's natural sleeping environment from masseter and temporalis muscles before injection, and 4, 8, and 12 wks after injection and then used to calculate bruxism events. Bruxism symptoms were investigated using questionnaires. RESULTS: Bruxism events in the masseter muscle decreased significantly in the botulinum toxin injection group (P = 0.027). In the temporalis muscle, bruxism events did not differ between groups or among times. Subjective bruxism symptoms decreased in both groups after injection (P < 0.001). CONCLUSIONS: Our results suggest that botulinum toxin injection reduced the number of bruxism events, most likely mediated its effect through a decrease in muscle activity rather than the central nervous system. We controlled for placebo effects by randomizing the interventions between groups, obtaining subjective and objective outcome measures, using the temporalis muscle as a control, and collecting data at three postinjection times. Our controlled study supports the use of botulinum toxin injection as an effective treatment for nocturnal bruxism.

Temporomandibular joint loads in subjects with and without disc displacement.

The likelihood of development of degenerative joint disease (DJD) of the temporomandibular joint (TMJ) is related to the integrity of the TMJ disc. Predilection for mechanical failure of the TMJ disc may reflect inter-individual differences in TMJ loads. Nine females and eight males in each of normal TMJ disc position and bilateral disc displacement diagnostic groups consented to participate in our study. Disc position was determined by bilateral magnetic resonance images of the joints. Three-dimensional (3D) anatomical geometry of each subject was used in a validated computer-assisted numerical model to calculate ipsilateral and contralateral TMJ loads for a range of biting positions (incisor, canine, molar) and angles (1-13). Each TMJ load was a resultant vector at the anterosuperi or-most mediolateral midpoint the condyle and characterized in terms of magnitude and 3D orientation. Analysis of variance (ANOVA) was used to test for effects of biting position and angle on TMJ loads. Mean TMJ loads in subjects with disc displacement were 9.5-69% higher than in subjects with normal disc position. During canine biting, TMJ loads in subjects with disc displacement were 43% (ipsilateral condyle, p=0.029) and 49% (contralateral condyle, p=0.015) higher on average than in subjects with normal disc position. Biting angle effects showed that laterally directed forces on the dentition produced ipsilateral joint loads, which on average were 69% higher (p=0.002) compared to individuals with normal TMJ disc position. The data reported here describe large differences in TMJ loads between individuals with disc displacement and normal disc position. The results support future investigations of inter-individual differences in joint mechanics as a variable in the development of DJD of the TMJ.

Waking-state oral parafunctional behaviors: specificity and validity as assessed by electromyography.

In contrast to sleep-related oral parafunctional behaviors, little is known about waking oral parafunctional behaviors. The Oral Behaviors Checklist contains terms referring to a variety of non-observable behaviors that are reliable when prompted (e.g. 'clench') but validity data are absent. Our goal was to assess whether (i) each behavioral term is distinct electromyographically, and (ii) temporomandibular disorder (TMD) subjects differ from non-TMD subjects in their performance. Surface electromyographic (EMG) activity was used to measure bilateral masseter, temporalis, and suprahyoid muscles while subjects (27 patients with TMD; 27 healthy controls) performed ten oral behaviors without explanation. Electromyographic data were averaged between bilateral muscles and two trials. A multivariate construct (jaw muscle activity) was analyzed using Wilks lambda within multivariate analysis of variance (manova). Obvious behaviors (e.g. clench, read, tongue press) exhibited expected EMG patterns, and patients and controls produced identical profile plots of the EMG data. Of 10 tested behaviors, nine were found to be associated with significantly differing proportions of amplitudes across muscles and were thus unique. Behaviors with similar terms were associated with different EMG patterns. The present data support the specificity of behavioral terms and performances. Implications include causation related to TMD based on subtle behaviors that occur at a high frequency.

[Visuospatial context processing in untreated schizophrenic patients and relation to disorganization syndrome]. / Traitement du contexte visuospatial chez des patients schizophrènes non traités -- influence de la désorganisation.

AIM: Previous studies on schizophrenia have suggested that context-processing disturbances were one of the core cognitive deficits present in schizophrenia. Schizophrenic patients have a failure either of inhibition strategy and maintenance of visuospatial information (25) in condition of contextual interference. In the present study, we explored the performances of untreated schizophrenic patients with 2 tasks exploring detection and long term retention of complex visual features and field dependence-independence tasks were selected. These abilities involve temporary maintenance of visuospatial information and executive functioning of visual working memory system. Several studies have shown that cognitive deficit may depend on schizophrenic symptomatology. However results remain controversial in determining the specific influence of negative and positive symptomatologies as well as clinical disorganization. Our goal was to explore the processing of spatial context and its relation to disorganized syndrome. This study was approved by the local ethic committee. METHODOLOGY: Thirty-six schizophrenic patients were included according to DSM IV criteria (19 neuroleptic naïve, 17 unmedicated patients during more than 3 months). Thirty-six healthy controls were matched to patients for age, gender and level of education. Absence of axis 1 pathology was attested for controls with SCID-NP. Current symptomatology was evaluated by the Positive and Negative Syndrome Scale (PANSS) (14). Clinical disorganisation was evaluated with the disorganisation score established upon a factorial analysis of PANSS by Lepine and Lançon. Items selected to distinguish the disorganised group were abstraction, disorganization, orientation, and attention. PROCEDURE: Two tasks of embedded figures were administered individually to patients and controls. The Faverge task (Research of Figures-RF) (10) evaluates the ability to recognize the target from spatial complex geometrical figures. The Group Embedded Figure Task (GEFT - Oltman) assesses the detection and maintenance of visual target and its recognition within a complex figure. Performance between patients and controls were compared with the Student T test. The comparison of two clinical subgroups of disorganized and low disorganized patients and control group was performed with an ANOVA. Tuckey test was used for pairwise comparisons. RESULTS: We defined two subgroups of patients, disorganized patients (subscore 12, n=17) and low disorganized patients (subscore<12, n=19). Theses 2 subgroups were similar for age and level of education. Concerning the two tasks, there was no significant difference between schizophrenic patients and normal controls. The comparison between subgroups of disorganized and low disorganized patients, for RF task, showed a decrease of correct answers with disorganized patients (p<0.05). For GEFT task, disorganized patients had a decrease of correct answers p<0.01) and more errors (p<0.01) and omissions (p<0.05). The low disorganized patients exhibited for the two tests comparable performance to controls. The disorganized patients had a decrease of right answers (p<0.05) and more errors (p<0.05) than controls for GEFT task and no significant difference for RF. However, with IQ (evaluated with an abstract reasoning test) introduced as covariate, only correct answers for GEFT task remain significant (p<0.05). DISCUSSION: The weak performance of disorganized schizophrenic patients for two tasks RF and GEFT showed that treatment of visuospatial information was impaired in the first perceptive phase of selection and in the organization of information (RF), especially with the maintenance of visual information in memory (GEFT). By contrast, low disorganized patients demonstrated a correct analytic treatment of elementary processing and visuospatial working memory. CONCLUSION: The severity of disorganization influences the visuospatial context processing and visuospatial working memory. These results show the heterogeneity of cognitive functioning regarding to schizophrenic symptomatologies. This difficulty could be related to a problem of central executive functioning in the visuospatial component of working memory, possibly mediated by the dysfunction of dorsolateral prefrontal cortex.

Individual variations in numerically modeled human muscle and temporomandibular joint forces during static biting.

AIMS: To test the effects of occlusal force (OF) angle on the variations in predicted muscle and temporomandibular joint (TMJ) forces during unilateral molar bites. METHODS: The craniomandibular (CM) geometries of 21 individuals were determined from lateral and posteroanterior cephalometric radiographs. These geometries were used in a numerical model based on minimization of muscle effort. This model was previously validated for this subject group through the use of jaw tracking and electromyographic data. The model predicted muscle and TMJ forces associated with static OFs on the right mandibular first molar. OF angle was varied from vertical to 40 degrees in the buccal and lingual directions, in increments of 10 degrees. RESULTS: Intra- and intersubject variations in predicted muscle and TMJ forces for unilateral molar biting were dependent on OF angle and CM geometry. Nonvertical OFs were associated with either large anterior temporalis muscle forces (> 100% of applied OF in 3 subjects) or large inferior lateral pterygoid muscle forces (> 90% of applied OF in 3 subjects). On average, vertically and buccally directed OFs were associated with higher mean contralateral TMJ forces (60% of applied OF, SD 12%). Two subjects had large ipsilateral or contralateral TMJ forces (> 90% of applied OF). CONCLUSION: In a group of healthy subjects, depending on the individual CM geometry, large muscle and/or TMJ forces were predicted to be associated with specific unilateral molar OF angles. Propensities to increased muscle or joint forces may be predisposing factors in the development of myofascial pain or intracapsular disease. The results may explain, in part, the variation in location of symptoms in individuals who first present with temporomandibular disorders.

[Predictive factors of response to buprenorphine in the substitutive treatment of heroin addicts. Results of a multicenter study of 73 patients]. / Facteurs prédictifs de la réponse à la buprénorphine en traitement substitutif des héroïnomanies. Résultats d'une étude multicentrique sur 73 patients.

OBJECTIVE: Buprenorphine has a partial morphine-agonist pharmacological profile. It is proposed as alternative to methadone in opiate drug addicts with greater safety of use and less cost in terms of public health. The aim of this study was to determine the clinical factors of response to this molecule. METHOD: The study was conducted in 73 patients treated for 3 months with adaptable doses. Mean dose was 8.5 mg/d (range: 3 to 16 mg/d). Response to treatment was defined as: still in the study at 3 months and absence of opiates in 75% of urinary samples over the past month. RESULTS: Forty-eight patients responded and 25 did not. The determinating clinical variables of response were: opiate drug addiction less than 10 years, high score on the Addiction Severity Index (ASI), absence of depression according to the Minnesota Multiphasic Personality Inventory (MMPI) and low rate of disinhibition on Zukerman's sensation seeking scale. Conversely, the dose of buprenorphine within the limits specified in the Marketing Authorisation did not intervene in the response. CONCLUSION: In view of its partial agonist effect, administration of buprenorphine must be reserved for patients addicted to opiates for less than 10 years, non-depressive and with low disinhibition on Zukerman's scale.

Spatially correlated fluorescence/AFM of individual nanosized particles and biomolecules.

Individual fluorescent polystyrene nanospheres (<10-100-nm diameter) and individual fluorescently labeled DNA molecules were dispersed on mica and analyzed using time-resolved fluorescence spectroscopy and atomic force microscopy (AFM). Spatial correlation of the fluorescence and AFM measurements was accomplished by (1) positioning a single fluorescent particle into the near diffraction-limited confocal excitation region of the optical microscope, (2) recording the time-resolved fluorescence emission, and (3) measuring the intensity of the excitation laser light scattered from the apex of an AFM probe tip and the AFM topography as a function of the lateral position of the tip relative to the sample substrate. The latter measurements resulted in concurrent high-resolution (approximately 10-20 nm laterally) images of the laser excitation profile of the confocal microscope and the topography of the sample. Superposition of these optical and topographical images enabled unambiguous identification of the sample topography residing within the excitation region of the optical microscope, facilitating the identification and structural characterization of the nanoparticle(s) or biomolecule(s) responsible for the fluorescence signal observed in step 2. These measurements also provided the lateral position of the particles relative to the laser excitation profile and the surrounding topography with nanometer-scale precision and the relationship between the spectroscopic and structural properties of the particles. Extension of these methods to the study of other types of nanostructured materials is discussed.

Solution studies of recombinant human stromal-cell-derived factor-1.

Stromal-cell-derived factor-1 (SDF-1alpha) is an 8-kDa chemokine that is constitutively expressed in bone-marrow-derived stromal cells and has been identified as a ligand for the CXCR4 receptor. We produced the chemokine recombinantly as methionine-SDF-1alpha in Escherichia coli without the leader peptide sequence. The protein was denatured, refolded, and further purified by reversed-phase HPLC. SDF-1alpha was shown to be >95% pure as judged by SDS-PAGE. The final yield of purified and refolded SDF-1alpha was 1-2 mg per gram of wet cell paste. The refolded protein is a ligand for the CXCR4 receptor and has been used to block HIV-mediated cell fusion and downmodulates the CXCR4 receptor. Our ability to purify hundreds of milligrams of refolded protein allowed us to conduct detailed studies of the biophysical properties of the protein. We have used a combination of biophysical techniques to study the solution properties of SDF-1alpha. The average mass of SDF-1alpha, as determined by static light scattering, gave us the first indications that the chemokine may self-associate. Further investigation with sedimentation velocity ultracentrifugation confirmed the existence of two species. The measured s(20, W) values defined two masses corresponding to monomer and dimer. Finally, sedimentation equilibrium ultracentrifugation and dynamic light scattering yielded a composite value of 150 +/- 30 microM for the dimerization constant. We conclude that SDF-1alpha exists in a monomer-dimer equilibrium.

Myostatin inhibits cell proliferation and protein synthesis in C2C12 muscle cells.

Myostatin mutations in mice and cattle are associated with increased muscularity, suggesting that myostatin is a negative regulator of skeletal muscle mass. To test the hypothesis that myostatin inhibits muscle cell growth, we examined the effects of recombinant myostatin in mouse skeletal muscle C2C12 cells. After verification of the expression of cDNA constructs in a cell-free system and in transfected Chinese hamster ovary cells, the human recombinant protein was expressed as the full-length (375-amino acid) myostatin in Drosophila cells (Mst375D), or the 110-amino acid carboxy-terminal protein in Escherichia coli (Mst110EC). These proteins were identified by immunoblotting and were purified. Both Mst375D and Mst110EC dose dependently inhibited cell proliferation (cell count and Formazan assay), DNA synthesis ([3H]thymidine incorporation), and protein synthesis ([1-14C]leucine incorporation) in C2C12 cells. The inhibitory effects of both proteins were greater in myotubes than in myoblasts. Neither protein had any significant effects on protein degradation or apoptosis. In conclusion, recombinant myostatin proteins inhibit cell proliferation, DNA synthesis, and protein synthesis in C2C12 muscle cells, suggesting that myostatin may control muscle mass by inhibiting muscle growth or regeneration.

Melanocortin receptor-mediated mobilization of intracellular free calcium in HEK293 cells.

Mouse melanocortin receptors, MC1-R, MC3-R, MC4-R, and MC5-R, when expressed in HEK293 cells and stimulated with either alpha-melanocyte-stimulating hormone (alpha-MSH) or desacetyl-alpha-MSH, mediate increases in intracellular free calcium concentration ([Ca(2+)](i)) with EC(50) values between 0.3 and 4.3 nM. The increase in [Ca(2+)](i) is cholera toxin sensitive and pertussis toxin insensitive. The mechanism involves calcium mobilization from intracellular stores without a transient rise in inositol trisphosphate. Mouse agouti protein (55 nM) is a competitive antagonist of alpha-MSH (6-fold) and desacetyl-alpha-MSH (8-fold), coupling the mMC1-R to increased [Ca(2+)](i). Agouti protein (55 nM) significantly increased the EC(50) for alpha-MSH (3-fold), and 550 nM agouti protein significantly increased the EC(50) for desacetyl-alpha-MSH (4-fold), coupling the mMC4-R to a rise in [Ca(2+)](i). However, agouti protein antagonism of the MC4-R may not be competitive since there was a trend for the maximum response to also increase. There was no significant antagonism of the MC3-R and MC5-R by agouti protein (55 nM). Understanding the physiological relevance of the transduction of a calcium signal by melanocortin peptides may be important for future development of therapeutic targeting of the melanocortin receptors.

Pollen assemblages as paleoenvironmental proxies in the Florida Everglades.

Analysis of 170 pollen assemblages from surface samples in eight vegetation types in the Florida Everglades indicates that these wetland sub-environments are distinguishable from the pollen record and that they are useful proxies for hydrologic and edaphic parameters. Vegetation types sampled include sawgrass marshes, cattail marshes, sloughs with floating aquatics, wet prairies, brackish marshes, tree islands, cypress swamps, and mangrove forests. The distribution of these vegetation types is controlled by specific environmental parameters, such as hydrologic regime, nutrient availability, disturbance level, substrate type, and salinity; ecotones between vegetation types may be sharp. Using R-mode cluster analysis of pollen data, we identified diagnostic species groupings; Q-mode cluster analysis was used to differentiate pollen signatures of each vegetation type. Cluster analysis and the modern analog technique were applied to interpret vegetational and environmental trends over the last two millennia at a site in Water Conservation Area 3A. The results show that close modern analogs exist for assemblages in the core and indicate past hydrologic changes at the site, correlated with both climatic and land-use changes. The ability to differentiate marshes with different hydrologic and edaphic requirements using the pollen record facilitates assessment of relative impacts of climatic and anthropogenic changes on this wetland ecosystem on smaller spatial and temporal scales than previously were possible.

Expression, purification, and characterization of the human receptor activator of NF-kappaB ligand (RANKL) extracellular domain.

Receptor activator of NF-kappaB ligand (RANKL) is a type II transmembrane protein found on osteoblasts which functions as a major determinant of osteoclast differentiation and activation. RANKL mediates bone homeostasis through binding to the cognate ligand on osteoclasts, RANK, and a soluble decoy receptor, osteoprotegerin (OPG). We designed a construct encoding the extracellular domain of human RANKL that conformed to reports of native processing. To encourage folding and posttranslational modification of a normally membrane-inserted moiety, we expressed the RANKL truncate as a secreted protein using the signal sequence from OPG in a Trichoplusia ni cell line using a baculovirus expression vector. RANKL was purified by a three-step process including an OPG-Fc affinity column. SDS-PAGE and mass spectral analysis indicated that the protein was >99% pure and glycosylated. Circular dichroism spectra revealed that the protein exhibited structural elements similar to tumor necrosis factor-alpha. By BIAcore analysis, RANKL bound to OPG with an affinity of 6.7 nM. Sedimentation equilibrium analytical ultracentrifugation analyses established that our protein existed as a trimer. We conclude that our expressed human RANKL truncate is folded, is functional, and exhibits self-association consistent with other family members.

[Clinical dimensions and visually guided saccades in schizophrenia]. / Dimensions cliniques et saccades visuellement guidées dans la schizophrénie.

Eye movement anomalies are more frequent in schizophrenic patients than in healthy subjects. This study deals with visually guided saccadic eye movements in seventeen schizophrenic patients [ten untreated (neuroleptic-naive or free), seven treated patients] and their correlations between symptoms presented by patients and oculomotor performances. There was no significant difference between the patients and the control group in visually guided saccades tasks. However, negative correlations between oculomotor performance and positive or disorganisation symptomatology were found. Thus, although no major oculomotor dysfunction in response to external stimulus was seen in schizophrenic patients, some symptoms were linked to oculomotor performance impairment. Thus psychiatric symptoms might share some common cerebral circuits which those involved in oculomotor tasks.