Reelin Signaling and Synaptic Plasticity in Schizophrenia

Recent research emphasizes the significance of studying the quality of life of schizophrenia patients, considering the complex nature of the illness. Identifying neuronal markers for early diagnosis and treatment is crucial. Reelin (RELN) stands out among these markers, with genetic studies highlighting its role in mental health. Suppression of RELN expression may contribute to cognitive deficits by limiting dendritic proliferation, affecting neurogenesis, and leading to improper neuronal circuits. Although the physiological function of reelin is not fully understood, it plays a vital role in hippocampal cell stratification and neuroglia formation. This analysis explores reelin's importance in the nervous system, shedding light on its impact on mental disorders such as schizophrenia, paving the way for innovative therapeutic approaches, and at the same time, raises the following conclusions: increased methylation levels of the RELN gene in patients with a diagnosis of schizophrenia results in a multiple decrease in the expression of reelin, and monitoring of this indicator, i.e., methylation levels, can be used to monitor the severity of symptoms in the course of schizophrenia.

Distribution of Iron, Copper, Zinc and Cadmium in Glia, Their Influence on Glial Cells and Relationship with Neurodegenerative Diseases

Recent data on the distribution and influence of copper, zinc and cadmium in glial cells are summarized. This review also examines the relationship between those metals and their role in neurodegenerative diseases like Alzheimer disease, multiple sclerosis, Parkinson disease and Amyotrophic lateral sclerosis, which have become a great challenge for today's physicians. The studies suggest that among glial cells, iron has the highest concentration in oligodendrocytes, copper in astrocytes and zinc in the glia of hippocampus and cortex. Previous studies have shown neurotoxic effects of copper, iron and manganese, while zinc can have a bidirectional effect, i.e., neurotoxic but also neuroprotective effects depending on the dose and disease state. Recent data point to the association of metals with neurodegeneration through their role in the modulation of protein aggregation. Metals can accumulate in the brain with aging and may be associated with age-related diseases.

Self-Regulatory Neuronal Mechanisms and Long-Term Challenges in Schizophrenia Treatment

Schizophrenia is a chronic and relapsing disorder that is characterized not only by delusions and hallucinations but also mainly by the progressive development of cognitive and social deficits. These deficits are related to impaired synaptic plasticity and impaired neurotransmission in the nervous system. Currently, technological innovations and medical advances make it possible to use various self-regulatory methods to improve impaired synaptic plasticity. To evaluate the therapeutic effect of various rehabilitation methods, we reviewed methods that modify synaptic plasticity and improve the cognitive and executive processes of patients with a diagnosis of schizophrenia. PubMed, Scopus, and Google Scholar bibliographic databases were searched with the keywords mentioned below. A total of 555 records were identified. Modern methods of schizophrenia therapy with neuroplastic potential, including neurofeedback, transcranial magnetic stimulation, transcranial direct current stimulation, vagus nerve stimulation, virtual reality therapy, and cognitive remediation therapy, were reviewed and analyzed. Since randomized controlled studies of long-term schizophrenia treatment do not exceed 2-3 years, and the pharmacological treatment itself has an incompletely estimated benefit-risk ratio, treatment methods based on other paradigms, including neuronal self-regulatory and neural plasticity mechanisms, should be considered. Methods available for monitoring neuroplastic effects in vivo (e.g., fMRI, neuropeptides in serum), as well as unfavorable parameters (e.g., features of the metabolic syndrome), enable individualized monitoring of the effectiveness of long-term treatment of schizophrenia.

Comparison of memory fMRI response among normal, MCI, and Alzheimer's patients

OBJECTIVE

To determine whether an fMRI memory encoding task distinguishes among cognitively normal elderly individuals, patients with mild cognitive impairment (MCI), and patients with early Alzheimer's disease (AD).

METHODS

Twenty-nine subjects (11 normal, 9 MCI, 9 AD) were studied with an fMRI memory encoding task. A passive sensory task was also performed to assess potential intergroup differences in fMRI responsiveness. Activation in the medial temporal lobe for the memory task and in the anatomic rolandic area for the sensory task was studied. Intergroup comparisons were performed using receiver operating characteristic (ROC) analyses. The ROC method provides rigorous control of artifactual false-positive "activation." Subjects were tested for recall and recognition of the encoding task stimuli following the fMRI study.

RESULTS

Medial temporal lobe activation was greater in normal subjects than MCI and AD patients (p = 0.03 and p = 0.04). There was no difference between AD and MCI patients in fMRI memory performance [corrected]. There was an association between fMRI memory activation (area under the ROC curve) and post-fMRI performance on recognition and free recall. There was no difference among the three groups on the sensory task.

CONCLUSIONS

MCI and AD patients had less medial temporal lobe activation on the memory task than the normal subjects but similar activation as normal subjects on the sensory task. These findings suggest decreased medial temporal activation may be a specific marker of limbic dysfunction due to the neurodegenerative changes of AD. In addition, fMRI is sufficiently sensitive to detect changes in the prodromal, MCI, phase of the disease.

[Standards, Options and Recommendations (SOR) for good practices in dentistry for head and neck cancer patients. Federation of the French Cancer Centres (FNCLCC)]

CONTEXT

The Standards, Options and Recommendations (SOR), initiated in 1993, is a collaborative project between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcomes for cancer patients. The methodology is based on literature review and critical appraisal by a multidisciplinary experts group, with feedback from specialists in cancer care delivery.

OBJECTIVES

To develop clinical practice guidelines for dentistry and oral hygiene in head and neck cancer patients.

METHODS

Data have been identified by literature search using Medline (up to January 1999) and personal reference lists. The main end points considered were risk factors for treatment related late effects, safety and quality of life, efficacy of dental preventative measures and treatment. Once the guidelines were defined, the document was submitted to reviewers for peer review and to the medical committees of the 20 French Cancer Centres for review and agreement.

RESULTS

The key recommendations are: 1) before receiving radiotherapy, surgery and chemotherapy for head and neck cancer, patients must benefit from a multidisciplinary approach including dental evaluation; 2) the patients must be informed of precautions and educated about oral hygiene; 3) after radiotherapy, the most important dental late effect to prevent is radionecrosis, in accordance with the oral and dental state, the dentist may propose conservation or extraction of teeth, fluoridation and regular follow-up; 4) during chemotherapy, the principal complications are mucositis, haemorrhage and infection risk; 5) after surgery, the dentist may propose prosthetic measures with the aim functional, aesthetic and psychological benefit; 6) in the particular case of children, treatment and prevention are the same as for adults but the follow-up is specific because of the dental development.

Prevention of oral mucositis in patients treated with high-dose chemotherapy and bone marrow transplantation: a randomised controlled trial comparing two protocols of dental care

Between February 1986 and November 1989, 166 patients who were candidates for a bone marrow transplantation entered a randomised controlled clinical trial to compare limited oral hygiene care (LIM) and intensive oral hygiene care (INT) in the prevention of mucositis. Randomisation was stratified on the initial oral status (good vs. bad IOS). Intensive oral hygiene care included an initial treatment of dental lesions and tooth and gum brushing during aplasia. Limited oral hygiene care excluded preventive dental treatment and gingival and tooth brushing. Mucositis was classified as absent, mild, moderate or severe, according to the clinical aspects of the different sites in the mouth and to two scales of pain evaluation. Of the 150 evaluable patients (75 in each group), 134 developed moderate/severe mucositis (64 in the INT group and 70 in the LIM group) (log-rank test P < 0.02). The superiority of intensive oral care was observed both in patients with and without total body irradiation (TBI) and in patients with a good or bad IOS; the observed risk of mucositis was reduced by 70% in each of these four subgroups. Duration of moderate/severe mucositis was, although not significantly, lower in the INT group (17 days, S.D. = 12) than in the LIM group (19 days, S.D. = 13). The median time of mucositis occurrence was 11 days in the INT group and 9 days in the LIM group. Contrary to a widespread belief, the percentage of documented septicaemia was not higher in patients who underwent intensive oral care. We conclude that, although statistically significant, the superiority of intensive oral hygiene care is not clinically impressive.(ABSTRACT TRUNCATED AT 250 WORDS)

[Orodental care before and after radiotherapy affecting the oral cavity]

This article shows that once topical fluoride applications have been prescribed, oral rehabilitations should be adapted to each patient. Post radiotherapy maintenance is also essential to maintain a good dental equilibrium. This adequate dental condition is the best preventive measure against late osteoradionecrosis of dental origin.