Sub-acute neuropathy in patients with African tick bite fever

African tick bite fever (ATBF) caused by Rickettsia africae is an emerging health problem in travellers to sub-Saharan Africa. We here present 6 patients with evidence of long-lasting sub-acute neuropathy following ATBF contracted during safari trips to southern Africa. Three patients developed radiating pain, paresthaesia and/or motor weakness of extremities, 2 had hemi-facial pain and paresthaesia, and 1 developed unilateral sensorineural hearing loss. When evaluated 3-26 months after symptom onset, cerebrospinal fluid samples from 5 patients were negative for R. africae PCR and serology, but revealed elevated protein content in 3 and mild pleocytosis in 1 case. Despite extensive investigations, no plausible alternative causes of neuropathy could be identified. Treatment with doxycycline in 2 patients had no clinical effect. Given the current increase of international safari tourism to sub-Saharan Africa, more cases of sub-acute neuropathy following ATBF may well be encountered in Europe and elsewhere in the y to come.     

Place of residence and distance to medical care influence the diagnosis of hepatitis C: a population-based study

BACKGROUND/AIMS: In France, geographic access to medical care may affect the diagnosis of hepatitis C. The aims of this study were to compare the detection rates of hepatitis C in urban and rural areas after adjusting for distance to medical care, and evaluating the impact of the place of residence on patients' clinical characteristics. METHODS: Between 1994 and 2001, 1938 newly detected cases were recorded in a French population of 1,005,817 inhabitants. Age and sex-adjusted detection rates for 10(5) inhabitants were estimated for urban and rural areas and for classes of distance to the nearest practitioner. RESULTS: Detection rates were lower in rural than in urban areas [14.1, (95CI: 12.5-15.7) versus 24.7, (95CI: 23.5-26.0)] and decreased as the distance to the general practitioner increased [27.0, (95CI: 25.5-28.4) versus 13.7, (95CI: 12.1-15.3) for a cutoff value of 1.5 km]. In multivariate analyses, detection rates were only influenced by the distance to general practitioner. Hepatocellular carcinoma at diagnosis was more frequent among rural than among urban patients (adjusted OR = 2.28, 95CI: 0.97-5.39, P = 0.059). CONCLUSIONS: A poorer geographic access to care explained the lower detection of hepatitis C in rural areas. Hepatocellular carcinoma was more frequent in rural patients. It may result from later detection and/or involvement of environmental factors on hepatocarcinogenesis.     

The diagnostic value of biomarkers (AshTest) for the prediction of alcoholic steato-hepatitis in patients with chronic alcoholic liver disease

BACKGROUND/AIMS: The aim was to identify a panel of biomarkers (AshTest) for the diagnosis of alcoholic steato-hepatitis (ASH), in patients with chronic alcoholic liver disease. METHODS: Biomarkers were assessed in patients with an alcohol intake>50 g/d, in a training group, and in two validation groups. Diagnosis of ASH (polymorphonuclear infiltrate and hepatocellular necrosis) and its histological severity (four classes: none, mild, moderate and severe) were assessed blindly. RESULTS: Two hundred and twenty-five patients were included, 70 in the training group, 155 in the validation groups, and 299 controls. AshTest was constructed using a combination of the six components of FibroTest-ActiTest plus aspartate aminotransferase. The AshTest area under the ROC curves for moderate-severe ASH was 0.90 in the training group, 0.88 and 0.89 in the validation groups. The median AshTest value was 0.005 in controls, 0.05 in patients without or with mild ASH, 0.64 in moderate, and 0.84 in severe ASH grade 3, (P<0.05 between all groups). At a 0.50 cut-off, the sensitivity of AshTest was 0.80 and the specificity was 0.84. CONCLUSIONS: In heavy drinkers, AshTest is a simple and non-invasive quantitative estimate of alcoholic hepatitis. The use of AshTest may reduce the need for liver biopsy, and therefore allow an earlier treatment of alcoholic hepatitis.     

High Maintenance Dosage of Clopidogrel is Associated with a Reduced Risk of Stent Thrombosis in Clopidogrel-Resistant Patients

Background

Stent thrombosis remains an important complication after stent implantation, despite the use of dual antiplatelet therapy with aspirin (acetylsalicylic acid) and clopidogrel. Several studies have shown an increased risk of thrombotic events in patients with resistance to clopidogrel. Some recent studies have suggested that a higher clopidogrel maintenance dosage could enhance ex vivo platelet inhibition and thereby overcome resistance to clopidogrel.

Objectives

To investigate whether a higher clopidogrel maintenance dosage is associated with a reduced risk of stent thrombosis after percutaneous coronary intervention (PCI) in clopidogrel-resistant patients and to evaluate the frequency of hemorrhagic accidents that could be associated with a high clopidogrel maintenance dosage.

Methods

An observational study was performed in 52 consecutive clopidogrel-resistant patients (resistance defined according to adenosine diphosphate-induced platelet aggregation assessment) who underwent a PCI with stenting at a tertiary referral center (Toulouse University Hospital, France). All patients received a clopidogrel loading dose of 300 mg, then 32 patients received a clopidogrel maintenance dosage of 75 mg/day (patients admitted between 2004 and 2005) and 20 patients received 150 mg/day (patients admitted in 2006). We compared the occurrence of definite stent thrombosis and hemorrhagic accidents between these two groups, using a regression model.

Results

Among the patients treated with clopidogrel 75 mg/day, 26 (81.3%) had definite stent thrombosis versus seven (35.0%) treated with 150 mg/day (adjusted relative risk [RR] 2.46; 95% CI 1.63, 2.76; p = 0.002). The risk of major adverse cardiac events (MACE) was also significantly lower in patients treated with 150 mg/day (adjusted RR 2.63; 95% CI 1.82, 2.82; p = 0.001). There was no significant difference between the two groups regarding hemorrhagic accidents.

Conclusion

Our data suggest that a high maintenance dosage of clopidogrel (150 mg/day) is associated with a reduced risk of definite stent thrombosis and MACE compared with a maintenance dosage of 75 mg/day. The frequency of hemorrhagic accidents was similar between the two groups, underlining a positive benefit-risk ratio of this strategy in clopidogrel-resistant patients. These findings deserve confirmation in a prospective, well conducted study.     

Rationale for a model of human systems integration: the need of a theoretical framework

Human systems integration (HSI) involves augmented human design with the objectives of augmenting human capabilities and improving human performance using behavioral technologies. The fundamental matter of human systems integration and augmented human design is the organization and the nature of interactions that couple physiological systems, humans- and engineered systems, artifacts. By this definition, augmented human consists of interactive artefacts linked to physiological systems. This paper focuses on the rationale of a HSI model based on specific experiments (comparison of dynamical sensorimotor integration and motor performances in real and virtual environments) that confirm the hypothesis of functional interaction in the framework of Chauvet's mathematical theory of integrative physiology (MTIP). Epistemological constraints for HSI and the role of MTIP are briefly discussed in this context.     

Ontogeny of the somatostatin variant [Pro2,Met13]somatostatin-14 in the brain, pituitary, and sensory organs of the frog Rana esculenta

Two forms of somatostatin are expressed in the frog brain, i.e., somatostatin-14 (SS1) and the [Pro(2), Met(13)]somatostatin-14 variant (SS2). We have previously described the ontogeny of SS1-immunoreactive cells in the brain of Rana esculenta. In the present study, we have investigated the distribution of prepro-SS2 (PSS2)-expressing neurons in the brain of the same species during development by using antibodies directed against the N-flanking region of SS2 (PSS2(54-66)). Immunoreactive perikarya first appeared in the ventral hypothalamus at stages IV-VII. Subsequently, positive neurons were seen in the nucleus of the diagonal band of Broca, the anterior preoptic area, the posterior tuberculum (stages VIII-XII), as well as the dorsal (stages XIII-XV) and medial (stages XIX-XX) periventricular preoptic nucleus. At metamorphic climax and in newly metamorphosed frogs, positive perikarya were found in the striatum and in the interpeduncular nucleus. PSS2(54-66)-immunoreactive fibers were already widely distributed during the first stages of development, indicating that SS2 may act as a neuromodulator and/or neurotransmitter during ontogeny. The presence of PSS2(54-66)-positive nerve fibers in olfactory structures suggests that, in tadpoles, SS2 may be involved in the processing of olfactory information. The occurrence of PSS2(54-66)-like immunoreactivity in taste buds, and in the olfactory and vomeronasal organs indicates that SS2 may mediate the unconditioned and reinforcing properties of natural chemicals. Finally, the intenseexpression of PSS2(54-66)-like immunoreactivity in melanotrope cells of the pituitary suggests that SS2 may diffuse toward the pars distalis to regulate the activity of adenohypophysial cells during tadpole development.     

Learned helplessness in children and adolescents with juvenile rheumatic disease

OBJECTIVE: To examine a learned helplessness conceptualization of psychological sequela in children and adolescents with juvenile rheumatic diseases (JRD) via an experimental procedure utilizing behavior-outcome contingent and noncontingent feedback. METHODS: Thirty-eight children and adolescents with JRD completed measures of transient affect, self-efficacy for functional ability, and causal attributions prior to and immediately following a computerized learned helplessness induction procedure. RESULTS: Children across contingent and noncontingent feedback conditions experienced decreased positive affect with a slightly more pronounced decline in the noncontingent condition. Noncontingent feedback resulted in poorer internalization of success for problem solving, while contingent feedback resulted in greater internalization of success for problem solving. Additionally, posttreatment control self-efficacy was significantly greater for children in the contingent condition that initially endorsed higher levels of internal task attributions. CONCLUSIONS: Children with JRD who experience behavior-outcome contingency in their environment may develop increased perceptions of control over functional ability. Furthermore, environmental noncontingency may result in poorer internalization of success, whereas contingent reinforcement may enhance cognitive appraisal mechanisms (i.e., causal attributions) associated with favorable disease outcome. Despite a modest decline in positive affect for children in the noncontingent condition, mood dysfunction is not entirely explicable within the context of noncontingent reinforcement.     

Culture of C. burnetii from the dental pulp of experimentally infected guinea pigs

An experimental model of Q fever in Guinea pigs was studied. Coxiella burnetii was cultured from the dental pulp of infected animals following bacteremia.     

Accuracy of distinguishing between dysembryoplastic neuroepithelial tumors and other epileptogenic brain neoplasms with [11C]methionine PET

Background

Dysembryoplastic neuroepithelial tumors (DNTs) represent a prevalent cause of epileptogenic brain tumors, the natural evolution of which is much more benign than that of most gliomas. Previous studies have suggested that [¹¹C]methionine positron emission tomography (MET-PET) could help to distinguish DNTs from other epileptogenic brain tumors, and hence optimize the management of patients. Here, we reassessed the diagnostic accuracy of MET-PET for the differentiation between DNT and other epileptogenic brain neoplasms in a larger population.

Methods

We conducted a retrospective study of 77 patients with focal epilepsy related to a nonrapidly progressing brain tumor on MRI who underwent MET-PET, including 52 with a definite histopathology. MET-PET data were assessed by a structured visual analysis that distinguished normal, moderately abnormal, and markedly abnormal tumor methionine uptake and by semiquantitative ratio measurements.

Results

Pathology showed 21 DNTs (40%), 10 gangliogliomas (19%), 19 low-grade gliomas (37%), and 2 high-grade gliomas (4%). MET-PET visual findings significantly differed among the various tumor types (P < .001), as confirmed by semiquantitative analyses (P < .001 for all calculated ratios), regardless of gadolinium enhancement on MRI. All gliomas and gangliogliomas were associated with moderately or markedly increased tumor methionine uptake, whereas 9/21 DNTs had normal methionine uptake. Receiver operating characteristics analysis of the semiquantitative ratios showed an optimal cutoff threshold that distinguished DNTs from other tumor types with 90% specificity and 89% sensitivity.

Conclusions

Normal MET-PET findings in patients with an epileptogenic nonrapidly progressing brain tumor are highly suggestive of DNT, whereas a markedly increased tumor methionine uptake makes this diagnosis unlikely.