Neuropathological analysis of an asymptomatic adult case with Dandy-Walker variant

The Dandy-Walker (DW) complex is a rare posterior fossa malformation, usually observed during the prenatal period or the early infancy. Clinically, it is characterized by mental retardation, seizures, cerebellar ataxia as well as symptoms of hydrocephalus. Structural imaging reveal a hypoplasia or agenesis of the cerebellar vermis, enlargement of the fourth ventricle with a posterior fossa cyst. Additional neurodevelopmental changes such as agenesis of the corpus callosum, lissencephaly and cortical dysplasia are also present. We report the first neuropathological analysis of an adult asymptomatic DW case. Brain computerized tomography showed a massive posterior fossa cyst and hypoplasia of the cerebellum. An Ehlers-Danlos syndrome type IV characterized by repetitive intestinal perforations and a saccular aneurysm on the left posterior communicating artery was also present. Macroscopic brain examination revealed hypoplasia of both cerebellar hemispheres and posterior part of the vermis, as well as dilatation of the fourth ventricle without hydrocephalus. The posterior fossa cyst wall was formed by an external arachnoid layer, middle layer with loose connective tissue and an internal layer of ependymal cells. There were two foci of cerebellar cortical dysplasia but no ectopic neurons, neuronal loss or gliosis in both cerebellum and cerebral cortex. No vascular or significant neurodegenerative lesions were observed. In comparison with previous reports in DW infants, this adult case displayed milder brain abnormalities compatible with a diagnosis of DW variant. The preservation of the cortical cytoarchitecture as well as the paucity of additional neurodevelopmental changes may explain the absence of clinical expressio

The neurocognitive deficit in schizophrenia: a review of existing data

Background: During the recent years, the focus of research on schizophrenia was moved to the cognitive deficits whose nature is extremely complex. Methods: The authors performed a selective review of the literature and included in the current article the papers they considered important according to their experience. Results: Today it is clear that most components of attention, are affected. There is not a primary deficit in a specific component of attention, however patients are typically slow and their volitional drive varies. The patients discriminative ability is dramatically reduced in direct relationship to the increase of the size of the series. Research so far supports the presence of deficits in the explicit part of remote memory, while the implicit part remains unaffected. It seems that patients with dominant positive symptoms manifest better neurocognitive function; the literature suggests that neurocognitive symptoms group independently from the other symptoms of psycho- sis. They are also present already during the early stages, and possibly even before positive symptoms. The neurobiological substrate of this deficit includes disorders located at least in the anterior cingulate, and the cortico-cerebellar-thalamo-cortical circuit. Conclusions: The neurocognitive deficit in schizophrenia is still not well understood and is considered to be the most significant predictor of long term outcome and of the ability of the patient to return in the community

Structured assessment of mental health status in psychogeriatrics: validity of the French HoNOS65+

OBJECTIVE: To assess the reliability, validity, and feasibility of a French version of the Health of the Nation Outcome Scales for Elderly People (HoNOS65+). METHOD: Twenty mental health professionals completed the scale for 126 elderly patients. We assessed interrater reliability in inpatient and outpatient settings, together with construct and discriminant validity, as well as concurrent validity compared with several widely used clinical instruments. RESULTS: Excellent agreement among raters was observed in the outpatient subgroup (kappa range 0.77 to 1.00), whereas interrater reliability was modest in the inpatient subgroup (kappa values < 0.55). In cases where the patient-caregiver relationship lasted more than 1 month, the reliability of the scale improved. Construct validity analysis revealed no subscale structure. All items except "self-injury" displayed high concurrent validity (significant Spearman correlations with 8 other questionnaires). In terms of discriminant validity, the "cognitive impairment" (area under the curve [AUC] 0.91) and "depressive symptoms" (AUC 0.79) items showed high sensitivity and specificity values. CONCLUSION: Our results indicate that the French version of HoNOS65+ is a promising clinical assessment tool to evaluate mental disorders in the elderly in outpatient settings. We support its use in routine clinical practice, with the condition that a relatively long and individualized patient-caregiver relationship has been established

HypothesisWorks/hypothesis: Hypothesis for Python - version 4.5.9

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A systematic review of existing data on long-term lithium therapy: neuroprotective or neurotoxic?

Lithium is an efficacious agent for the treatment of bipolar disorder, but it is unclear to what extent its long-term use may result in neuroprotective or toxic consequences. Medline was searched with the combination of the word 'Lithium' plus key words that referred to every possible effect on the central nervous system. The papers were further classified into those supporting a neuroprotective effect, those in favour of a neurotoxic effect and those that were neutral. The papers were classified into research in humans, animal and in-vitro research, case reports, and review/opinion articles. Finally, the Natural Standard evidence-based validated grading rationale was used to validate the data. The Medline search returned 970 papers up to February 2006. Inspection of the abstracts supplied 214 papers for further reviewing. Eighty-nine papers supported the neuroprotective effect (6 human research, 58 animal/in vitro, 0 case reports, 25 review/opinion articles). A total of 116 papers supported the neurotoxic effect (17 human research, 23 animal/in vitro, 60 case reports, 16 review/opinion articles). Nine papers supported no hypothesis (5 human research, 3 animal/in vitro, 0 case reports, 1 review/opinion articles). Overall, the grading suggests that the data concerning the effect of lithium therapy is that of level C, that is 'unclear or conflicting scientific evidence' since there is conflicting evidence from uncontrolled non-randomized studies accompanied by conflicting evidence from animal and basic science studies. Although more papers are in favour of the toxic effect, the great difference in the type of papers that support either hypothesis, along with publication bias and methodological issues make conclusions difficult. Lithium remains the 'gold standard' for the prophylaxis of bipolar illness, however, our review suggests that there is a rare possibility of a neurotoxic effect in real-life clinical practice even in closely monitored patients with 'therapeutic' lithium plasma levels. It is desirable to keep lithium blood levels as low as feasible with prophylaxis