Chimerism in Lymphoid Tissues and Donor-Specific Antibody Response After Injection of Allogenic Splenic Dendritic Cells From Fischer Rats to Lewis Recipients

The aim of this work was to study cellular chimerism achieved in lymphoid tissues and production of antidonor lymphocyte antibodies after injection of splenic dendritic cells (DCs) from Fischer F344 rats to Lewis recipients, a model of chronic rejection. DCs isolated from the spleen expressed OX62 (95%), CD80 (70%), and CD86 (80%). Two doses of these nonplasmacytoid splenic DCs from Fischer rats (2 x 10(6) and 5 x 10(6)), which had been labeled ex vivo with a TRITC fluorochrome (PKH26), were injected to Lewis recipients. Using fluorescence microscopy TRITC positive cells were localized at day 15 and day 45 in frozen sections from spleen, thymus, mesenteric lymph nodes, heart, liver, kidney, and skin (n = 5 per group). Donor-specific antibodies were sought with flow cytometric crossmatches in serum samples taken at 7, 15, 30, and 45 days. TRITC-positive DCs were essentially localized in the spleen, the thymus, and lymph nodes of Lewis recipients. The majority of DCs were detected in the spleen (14.9 +/- 3.3 and 14.3 +/- 0.9 DCs/per high power field respectively at day 45). A significant number of DCs was also detected in the thymus and mesenteric lymph nodes at both times. Only some scattered TRITC-positive cells were observed in other organs. The number of DCs was stable over time and did not depend on the injected dose. A positive flow cytometric cross-match was observed at day 30 in all recipients independent of the injected dose. These data showed that 2 x 10(6) mature, nonplasmocytoid DCs from F344 rats injected to Lewis recipients induced stable chimerism in primary and secondary lymphoid organs and a humoral response to donor antigens.

Hippocampus and amygdala morphology in attention-deficit/hyperactivity disorder

CONTEXT

Limbic structures are implicated in the genesis of attention-deficit/hyperactivity disorder (ADHD) by the presence of mood and cognitive disturbances in affected individuals and by elevated rates of mood disorders in family members of probands with ADHD.

OBJECTIVE

To study the morphology of the hippocampus and amygdala in children with ADHD.

DESIGN

A cross-sectional case-control study of the hippocampus and amygdala using anatomical magnetic resonance imaging.

SETTINGS

University research institute.

PATIENTS

One hundred fourteen individuals aged 6 to 18 years, 51 with combined-type ADHD and 63 healthy controls.

MAIN OUTCOME MEASURES

Volumes and measures of surface morphology for the hippocampus and amygdala.

RESULTS

The hippocampus was larger bilaterally in the ADHD group than in the control group (t = 3.35; P < .002). Detailed surface analyses of the hippocampus further localized these differences to an enlarged head of the hippocampus in the ADHD group. Although conventional measures did not detect significant differences in amygdalar volumes, surface analyses indicated the presence of reduced size bilaterally over the area of the basolateral complex. Correlations with prefrontal measures suggested abnormal connectivity between the amygdala and prefrontal cortex in the ADHD group. Enlarged subregions of the hippocampus tended to accompany fewer symptoms.

CONCLUSIONS

The enlarged hippocampus in children and adolescents with ADHD may represent a compensatory response to the presence of disturbances in the perception of time, temporal processing (eg, delay aversion), and stimulus seeking associated with ADHD. Disrupted connections between the amygdala and orbitofrontal cortex may contribute to behavioral disinhibition. Our findings suggest involvement of the limbic system in the pathophysiology of ADHD.

Masques laryngés à usage unique vs réutilisable : une étude de minimisation de coûts

JUSTIFICATION

According to French regulations concerning the risk of Creutzfeldt-Jakob disease transmission, traceability procedures of all sterile medical devices which need to be reused are mandatory. Despite sterilization processes, the reusable laryngeal mask airway (LMA) prion disease transmission remains possible. As a result, the disposable LMA has been introduced.

OBJECTIVE

Assuming clinical equivalence was achieved, the cost of disposable vs reusable LMA was studied in a university hospital.

STUDY DESIGN

A Cost-minimization analysis of disposable vs reusable laryngeal mask airway was realised.

METHODS

Disposable LMA cost was calculated as the sum of product cost and elimination cost. Reusable LMA were autoclaved after hospital purchasing in two separate sterilizing processing units of the same hospital. Reusable LMA cost was determined combining materiel and labor costs.

RESULTS

The reusable LMA cost depended on the sterilizing processing unit concerned and varied between 9.59 Euros and 9.69 vs 8.38 Euros for the single-use LMA.

CONCLUSION

With the cost savings made possible by use of disposable LMA in both labor and consumables, this practice should be considered.

Augmentation de l’hémoglobine A2 au cours du pseudoxanthome élastique

BACKGROUND

Pseudoxanthoma elasticum (PXE) is normally associated with mutations in the ABCC6 gene. A PXE phenotype without mutations in ABCC6 has been described in Greek and Italian patients presenting with beta thalassemia. We attempted to determine the incidence of beta thalassemia in a cohort of French patients with PXE.

PATIENTS AND METHODS

Fifty patients with PXE were included in the study. Laboratory examinations comprised hemoglobin electrophoresis, ABCC6 gene study and in some studies: mutation analysis, beta-globin gene.

RESULTS

No cases of beta thalassemia were diagnosed in this cohort of French patients with PXE. However, 20% of the latter exhibited a significant but isolated (i.e. without microcytic anemia) increase of hemoglobin A2 (HbA2). Statistical comparisons showed no difference in terms of geographical origin or severity of PXE between patients with high levels of HbA2 and those with normal levels of HbA2 other than the extent of cutaneous involvement. Study of the beta-globin gene displayed mutations only in the two patients with the highest recorded levels of HbA2. ABCC6 + beta-globin digenism was ruled out of the pathogenesis of PXE.

DISCUSSION

The PXE phenotype seen in some patients with beta thalassemia appears to be associated with epigenetic modification of ABCC6 transcription and depends specifically on the beta globin locus. Isolated increase in HbA2 is probably a laboratory marker for PXE. Here again, a functional epigenetic reaction between ABCC6 and the beta-globin locus was suspected. However, these reciprocal interactions are clearly unequal since the change in ABCC6 transcription occurring during the course of beta thalassaemia is responsible for a PXE phenotype while increased HbA2 during the course of PXE has no clinical consequences.

Ultrafractionated radiation therapy (3x per day) for glioblastoma: Preliminary results of a phase II study

1570

Background: Ultrafractionation radiation therapy consists in irradiating cells or tumors several times daily, delivering low doses at which hyperradiosensitivity occur. We recently reported the high efficiency of ultrafractionation radiotherapy in glioma cell lines and xenografts, and are now conducting a phase II clinical trial to determine the effect of an ultrafractionation regimen for glioblastoma patients. Methods: A prospective, multicenter, phase II study has opened for accrual in September 2003. Patients over 18 years of age who are able to give informed consent and have histologically proven, newly diagnosed and unresectable, supratentorial glioblastoma (WHO grade IV) are eligible. Three doses of 0.75 Gy spaced by at least four hours are delivered daily, five days a week for six consecutive weeks for a total of 67.5 Gy. Conformal irradiation includes the tumor bulk including a margin of 2.5 cm. Tolerance and toxicity are the primary endpoints; survival and progression-free survival are secondary endpoints. Results: To date 25 patients have been enrolled in this study, 19 currently evalualbe: 11 men and 8 women, median age 58 (range 37 to 76), median Karnofsky performance status (80 range from 70 to 100). The median time between histological diagnosis and the start of treatment is 7 weeks. The ultrafractionated radiation therapy has been well tolerated; no acute grade 3 and/or 4 CNS toxicity has been observed. Minor responses at the end of irradiation were seen in 5 patients. Median survival from initial diagnosis was 13.5 months, nine patients remain alive. Conclusions: Ultrafractionated radiation therapy is safe and well tolerated. No acute CNS toxicitiy has been observed. Overall survival of over 13 months for patients without prior debulking surgery compares favorably with other reports. Updated definitive results will be presented.

No significant financial relationships to disclose.

Proof-of-Concept Trial of an α7 Nicotinic Agonist in Schizophrenia

CONTEXT

The alpha7 nicotinic acetylcholine receptor gene, CHRNA7, is associated with genetic transmission of schizophrenia and related cognitive and neurophysiological sensory gating deficits. Cognitive dysfunction is responsible for significant psychosocial disability in schizophrenia. Nicotine, a low-potency agonist at the alpha7 receptor, has some positive effects on neurophysiological and neurocognitive deficits associated with schizophrenia, which suggests that more effective receptor activation might meaningfully enhance cognition in schizophrenia.

OBJECTIVES

To determine if 3-[(2,4-dimethoxy)benzylidene]anabaseine (DMXB-A), a natural alkaloid derivative and a partial alpha7 nicotinic cholinergic agonist, significantly improves neurocognition, and to assess, by effects on P50 auditory evoked potential inhibition, whether its neurobiological actions are consistent with activation of alpha7 nicotinic receptors.

DESIGN

Randomized, double-blind crossover trial of 2 drug doses and 1 placebo.

SETTING

General clinical research center.

PATIENTS

Twelve persons with schizophrenia who did not smoke and were concurrently treated with antipsychotic drugs. One person was withdrawn because of a transient decrease in white blood cell count.

INTERVENTION

Administration of DMXB-A.

MAIN OUTCOME MEASURES

Total scale score of the Repeatable Battery for the Assessment of Neuropsychological Status and P50 inhibitory gating.

RESULTS

Significant neurocognitive improvement was found on the Repeatable Battery for the Assessment of Neuropsychological Status total scale score, particularly for the lower DMXB-A dose compared with placebo. Effects were greater than those of nicotine in a similar study. Significant improvement in P50 inhibition also occurred. Patients generally tolerated the drug well.

CONCLUSIONS

An alpha7 nicotinic agonist appears to have positive effects on neurocognition in persons with schizophrenia. Longer trials are needed to determine the clinical utility of this novel treatment strategy.

Perception of very small visual stimuli in the fovea: normative data for the Rarebit Foveal Test

BACKGROUND

Conventional visual tests are not sensitive enough to detect low degree neural damage, as 6/6 (1.0) visual acuity can be upheld with less than two-thirds of the normal number of optic nerve axons. The aim of the current study was to evaluate the physiologic properties of a new computerised test, the Rarebit Fovea Test (RFT), using very small stimuli, by quantifying the effect of age and binocular summation in relation to stimulus luminance.

METHODS

The RFT relies on the perception of very small (less than 0.5 minutes of arc) bright stimuli. Two different experiments were performed. 1. Thirty-five subjects (age 19 to 63 years) were tested with five different stimulus luminances, 158, 64, 53, 41 and 33 cd/m(2). 2. Nineteen subjects (age 19 to 63 years) were tested using binocular stimulation to define the binocular summation.

RESULTS

Significantly reduced median hit rates were observed at luminances of 53 cd/m(2) or below. Age and mean hit rate correlated negatively at all luminance levels below 158 cd/m(2). The mean hit rate from binocular stimulation, compared to the highest value from monocular stimulation in the same subject, was increased by a factor of 1.54 +/- 0.45 (SD). No age effect was found regarding binocular summation.

CONCLUSIONS

The results in the current study indicate that RFT can identify some of the well-known features of the visual system, that is, the effects of age and binocular summation, provided that the stimulus luminance is adequately selected.

Characterization of antimicrobial resistance of Salmonella Newport isolated from animals, the environment, and animal food products in Canada

Multi-drug-resistant (MDR) Salmonella enterica serovar Newport strains are increasingly isolated from animals and food products of animal origin and have caused septicemic illness in animals and humans. The purpose of this study was to determine the occurrence and the epidemiologic, phenotypic, and genotypic characteristics of S. Newport of animal origin that may infect humans, either via the food chain or directly. During the 1993-2002 period, the Office International des Epizooties Reference Laboratory for Salmonellosis in Guelph, Ontario, received 36 841 Salmonella strains for serotyping that had been isolated from animals, environmental sources, and food of animal origin in Canada. Of these, 119 (0.3%) were S. Newport. Before 2000, none of 49 S. Newport strains was resistant to more than 3 antimicrobials. In contrast, between January 2000 and December 2002, 35 of 70 isolates, primarily of bovine origin, were resistant to at least 11 antimicrobials, including the extended-spectrum cephalosporins. The blaCMY-2', flo(st'), strA, strB, sulII, and tetA resistance genes were located on plasmids of 80 to 90 MDa that were self-transmissible in 25% of the strains. Conserved segments of the integron 1 gene were found on the large MDR-encoding plasmids in 3 of 35 strains additionally resistant to gentamicin and spectinomycin or to spectinomycin, sulfamethoxazole-trimethoprim, and trimethoprim. Resistance to kanamycin and neomycin was encoded by the aphA-1 gene, located on small plasmids (2.3 to 6 MDa). The increase in bovine-associated MDR S. Newport infections is cause for concern since it indicates an increased risk of human acquisition of the infection via the food chain.

Age, rapid-cycling, and pharmacotherapy effects on ventral prefrontal cortex in bipolar disorder: a cross-sectional study

BACKGROUND

Neuroimaging data suggest that deficits in ventral prefrontal cortex (VPFC) function in bipolar disorder (BD) progress during adolescence and young adulthood. However, the developmental trajectory of VPFC morphological abnormalities in BD is unknown. This study investigated potential age-dependent volume abnormalities in VPFC in BD.

METHODS

Thirty-seven individuals diagnosed with BD I (14 adolescents, 10 young adults and 13 older adults) and 56 healthy comparison subjects (HC) participated in imaging. Gray and white matter volumes of VPFC were measured using high-resolution structural magnetic resonance imaging (MRI). We used a mixed model, repeated measures analysis to examine VPFC volumes across age groups while co-varying for total brain volume. Potential effects of illness features including rapid-cycling and medication were explored.

RESULTS

VPFC volumes declined with age (p < .001). The diagnosis-by-age group interaction was significant (p = .01). Relative to HC subjects, VPFC gray and white matter volumes were significantly smaller in BD patients only in young adulthood (p = .04). In participants with BD, VPFC volumes were significantly smaller in participants with rapid-cycling than participants without rapid-cycling (p = .02). Conversely, current use of medication was associated with larger VPFC gray matter volumes (p = .005), independent of age.

CONCLUSIONS

These preliminary findings suggest the presence of a more rapid initial decline in VPFC volumes with age in adolescents and young adults with BD than HC. These findings also suggest that the rapid-cycling subtype of BD is associated with larger VPFC volume deficits than the non-rapid-cycling subtype, and that pharmacotherapy may have trophic or protective effects on VPFC volumes in BD patients.

Modulation of NMDA receptors by pituitary adenylate cyclase activating peptide in CA1 neurons requires G alpha q, protein kinase C, and activation of Src

At CA1 synapses, activation of NMDA receptors (NMDARs) is required for the induction of both long-term potentiation and depression. The basal level of activity of these receptors is controlled by converging cell signals from G-protein-coupled receptors and receptor tyrosine kinases. Pituitary adenylate cyclase activating peptide (PACAP) is implicated in the regulation of synaptic plasticity because it enhances NMDAR responses by stimulating Galphas-coupled receptors and protein kinase A (Yaka et al., 2003). However, the major hippocampal PACAP1 receptor (PAC1R) also signals via Galphaq subunits and protein kinase C (PKC). In CA1 neurons, we showed that PACAP38 (1 nM) enhanced synaptic NMDA, and evoked NMDAR, currents in isolated CA1 neurons via activation of the PAC1R, Galphaq, and PKC. The signaling was blocked by intracellular applications of the Src inhibitory peptide Src(40-58). Immunoblots confirmed that PACAP38 biochemically activates Src. A Galphaq pathway is responsible for this Src-dependent PACAP enhancement because it was attenuated in mice lacking expression of phospholipase C beta1, it was blocked by preventing elevations in intracellular Ca2+, and it was eliminated by inhibiting either PKC or cell adhesion kinase beta [CAKbeta or Pyk2 (proline rich tyrosine kinase 2)]. Peptides that mimic the binding sites for either Fyn or Src on receptor for activated C kinase-1 (RACK1) also enhanced NMDAR in CA1 neurons, but their effects were blocked by Src(40-58), implying that Src is the ultimate regulator of NMDARs. RACK1 serves as a hub for PKC, Fyn, and Src and facilitates the regulation of basal NMDAR activity in CA1 hippocampal neurons.

Clinical variants of the preprotuberant stage of dermatofibrosarcoma protuberans

BACKGROUND

Some cases of dermatofibrosarcoma protuberans (DFSP) do not protrude above the skin.

OBJECTIVES

To assess the prevalence of these DFSPs and further to describe their presentation and course.

METHODS

One hundred and forty-three patients were retrospectively collected. They were asked to complete a standardized questionnaire indicating the history and appearance of the DFSP from the first skin changes identified to the time of diagnosis.

RESULTS

Eighty-one DFSPs were described as protuberant ab initio, and 62 as initially nonprotuberant (npDFSP). The latter remained at this stage for a mean period of 7.6 years. Twenty-nine per cent of npDFSPs were 'morphoea-like', 19% were 'atrophoderma-like' and 42% were 'angioma-like'. Age at diagnosis was similar for both initial presentations. npDFSPs were most often misdiagnosed by physicians.

CONCLUSIONS

Nearly half the patients first identified their early DFSP-related skin changes as patches. Both this frequency and the long duration at this preprotuberant stage should prompt dermatologists to consider the diagnosis of DFSP earlier, in order to make surgical treatment easier.

Early biomarkers of psychosis

Biological traits that are predictive of the later development of psychosis have not yet been identified. The complex, multidetermined nature of schizophrenia and other psychoses makes it unlikely that any single biomarker will be both sensitive and specific enough to unambiguously identify individuals who will later become psychotic. However, current genetic research has begun to identify genes associated with schizophrenia, some of which have phenotypes that appear early in life. While these phenotypes have low predictive power for identifying individuals who will become psychotic, they do serve as biomarkers for pathophysiological processes that can become the targets of prevention strategies. Examples are given from work on the role of the alpha(T)nicotinic receptor and its gene CHRNA7 on chromosome 15 in the neurobiology and genetic transmission of schizophrenia.

Prostate Specific Antigen Isoforms and Human Glandular Kallikrein 2—Which Offers the Best Screening Performance in a Predominantly Black Population?

PURPOSE

Free prostate specific antigen, complexed PSA and human glandular kallikrein 2 have independently been tested against the gold standard of total PSA for prostate cancer screening in largely white populations. With the incidence of prostate cancer much higher in black men, we sought to evaluate these markers simultaneously in a predominantly black population.

MATERIALS AND METHODS

A total of 138 men, of whom 108 were black, underwent ultrasound guided biopsy of the prostate for tPSA levels greater than 2.5 ng/ml or an abnormal digital rectal examination. Sera were drawn before biopsy and analyzed for tPSA, fPSA, cPSA and hK2 concentrations using standard methods (hK2 assay is for research use only, not for use in diagnostic procedures). The areas under the receiver operator characteristic curves were determined for each marker as well as biomarker combinations. Additionally, each parameter's specificity, positive and negative predictive values, and theoretical screening efficiency were assessed at or above the 95% sensitivity level.

RESULTS

A total of 43 (31.1%) men had prostate cancer by biopsy. While the AUC for %fPSA was statistically the highest (0.822, p <0.001), cPSA offered the highest specificity (31.6%) and positive predictive power (31.7%) of any of the tested biomarkers at comparable sensitivity (greater than 95%). The calculated efficiency of cPSA (51.4%) was also higher than the other markers. Nearly 20% of biopsies would be avoided using cPSA vs standard tPSA screening methods.

CONCLUSIONS

Comparing the major PSA isoforms and hK2, cPSA alone appears to offer superior diagnostic discrimination for cancer detection in a predominantly black population.

Colonic fermentation of inulin increases whole-body acetate turnover in dogs

Metabolism of acetate from colonic fermentation was investigated in dogs. Beagle dogs (n = 9) were fed a control diet for 17 d followed by a 3% inulin-enriched diet (from chicory) for 4 and 21 d. On 3 occasions, the dogs were administered simultaneously infusions of [1-(13)C]acetate i.v. and [1,2-(13)C(2)]acetate intrarectally. Peripheral acetate concentration and turnover did not change over time after consumption of an inulin-enriched diet for 4 d. After 21 d of consuming the inulin-enriched diet, the whole-body acetate turnover increased significantly by 31% from (mean +/- SEM) 15.6 +/- 2.2 to 20.4 +/- 2.9 micromol/(kg . min) without a change in concentration. The rate of colonic acetate production that reached the peripheral circulation was 4.8 +/- 1.8 micromol/(kg . min). However, no [1,2-(13)C(2)]acetate tracer was recovered in the peripheral circulation. The fraction of oxidized tracer was higher in the gut (64 +/- 3%) than in peripheral circulation (46 +/- 3%) in dogs fed an inulin-enriched diet for 21 d. In conclusion, colonic fermentation of inulin occurred and indirectly stimulated whole-body acetate turnover in dogs fed an inulin-enriched diet for 21 d.

Distributions of charged hadrons associated with high transverse momentum particles in pp and Au+Au collisions at sqrt[sNN]=200 GeV

Charged hadrons in [EQUATION: SEE TEXT] associated with particles of [EQUATION: SEE TEXT] are reconstructed in pp and Au+Au collisions at sqrt[sNN]=200 GeV. The associated multiplicity and p magnitude sum are found to increase from pp to central Au+Au collisions. The associated p distributions, while similar in shape on the nearside, are significantly softened on the awayside in central Au+Au relative to pp and not much harder than that of inclusive hadrons. The results, consistent with jet quenching, suggest that the awayside fragments approach equilibration with the medium traversed.

Warfarin-induced small bowel obstruction

We present a rare case of small bowel obstruction in a patient on long-term anticoagulation. A 53-year woman presented with abdominal pain and vomiting. She was on warfarin following aortic and mitral valve surgery. A small bowel follow through revealed jejunal narrowing consistent with a stricture. This probably was the result of submucosal bleeding because of over warfarinazation. The warfarin was stopped and she started on heparin with complete resolution of symptoms. This rare complication of anticoagulation should be considered in patients on warfarin. Early diagnosis is crucial as most patients are treated conservatively with very few patients requiring surgery.

Multistrange Baryon elliptic flow in Au+Au collisions at square root of sNN=200 GeV

We report on the first measurement of elliptic flow v2(pT) of multistrange baryons Xi- +Xi+ and Omega- + Omega+ in heavy-ion collisions. In minimum-bias Au+Au collisions at square root of s(NN)=200 GeV, a significant amount of elliptic flow, comparable to other nonstrange baryons, is observed for multistrange baryons which are expected to be particularly sensitive to the dynamics of the partonic stage of heavy-ion collisions. The pT dependence of v2 of the multistrange baryons confirms the number of constituent quark scaling previously observed for lighter hadrons. These results support the idea that a substantial fraction of the observed collective motion is developed at the early partonic stage in ultrarelativistic nuclear collisions at the Relativistic Heavy Ion Collider.

Syndrome babouin associé à une polysensibilisation aux corticoïdes

BACKGROUND

The Baboon syndrome is a form of systemic contact dermatitis. We report the case of a patient who presented a Baboon syndrom following oral medication with betamethasone.

CASE REPORT

A 58 year-old man had consulted for eczema involving the groin, the buttocks and the axillae. It was clinically a baboon syndrome related to oral betamethasone (Celestene) treatment, ingested 48 hours earlier. The exploration with a patch-test confirmed the sensitization to betamethasone. This exploration also showed a sensitization to all four classes of corticosteroids. Prolonged withdrawal of all corticosteroids led to the clear improvement of his eczema.

DISCUSSION

The baboon syndrome of this patient was the symptom of a systemic eczema due to betamethasone. The patient was sensitized by the percutaneous route. The application of many topical corticosteroids had provoked this polysensitization. It was impossible to consider a safe corticosteroid for this patient.

Multiplicity and pseudorapidity distributions of photons in Au+Au collisions at square root of (S(NN)) = 62.4 GeV

We present the first measurement of pseudorapidity distribution of photons in the region 2.3 < or = eta < or = 3.7 for different centralities in Au+Au collisions at square root of (S(NN)) = 62.4 GeV. We find that the photon yield scales with the number of participating nucleons at all collision centralities studied. The pseudorapidity distribution of photons, dominated by pi0 decays, has been compared to those of charged pions, photons, and inclusive charged particles from heavy-ion and nucleon-nucleon collisions at various energies. The photon production has been shown to be consistent with the energy and centrality independent limiting fragmentation scenario.