Gut-microbiome-brain axis: the crosstalk between the vagus nerve, alpha-synuclein and the brain in Parkinson's disease.

This critical review of the literature shows that there is a close link between the microbiome, the gut, and the brain in Parkinson's disease. The vagus nerve, the main component of the parasympathetic nervous system, is involved in the regulation of immune response, digestion, heart rate, and control of mood. It can detect microbiota metabolites through its afferents, transferring this gut information to the central nervous system. Preclinical and clinical studies have shown the important role played by the gut microbiome and gut-related factors in disease development and progression, as well as treatment responses. These findings suggest that the gut microbiome may be a valuable target for new therapeutic strategies for Parkinson's disease. More studies are needed to better understand the underlying biology and how this axis can be modulated for the patient's benefit.

Impact of dysexecutive syndrome in quality of life in Alzheimer disease: What we know now and where we are headed.

Alzheimer's disease (AD) is a common form of dementia that leads to multiple repercussions in the patient's life. This condition's clinical characteristics include loss of memory, temporal and spatial disorientation, language or executive dysfunction, and subsequent decline of social function. Dysexecutive syndrome (DS), the second most frequent neuropsychological dysfunction in AD, affects multiple brain areas and causes cognitive, behavioral, and emotional difficulties. We aimed to analyze the association between DS and AD and elucidate possible lack of evidence that may urge further research on this theme. Especially when dealing with such a disabling disease, where new findings can directly imply a better prognosis.

Reversible cerebral vasoconstriction syndrome associated with probable drug poisoning.

Reversible cerebral vasoconstriction syndrome (RCVS) is a clinical condition characterized by arterial involvement of the intracranial vessels, manifesting with vasospasm. The most common clinical manifestation related to the syndrome is the thunderclap headache, which consists of a severe headache that reaches the peak of pain within minutes. The imaging study assumes a leading role in the complementary investigation. Laboratory tests and cerebrospinal fluid analysis are often nonspecific and without significant diagnostic importance. Non-contrast studies of the brain parenchyma reveal variable results that can often be normal. Angiographic findings, which initially may not reveal any changes, allow the visualization of diffuse narrowing of the vessels, with the posterior cerebral circulation being preferentially affected. The present study reports the case of a 19-year-old woman with no relevant medical history, except that she was a regular user of marijuana and a drug based on chloroform and ether. The patient showed clinical and imaging signs compatible with RCVS, and the narcotics used by her were considered precipitating factors.