[Descriptive epidemiology and frequency variations of astrocytic tumors in the National Institute of Neurology and Neurosurgery of Mexico]. / Epidemiología descriptiva y cambios en la frecuencia de tumores astrocíticos en el Instituto Nacional de Neurología y Neurocirugía de México.

OBJECTIVE: To determine distribution, localization and frequency variations of astrocytic tumors (AT) in a Mexican Institute of neurology. MATERIALS AND METHODS: Institutional registries of AT from five decades were analyzed. AT/ Surgical discharges (SD) and AT/Central Nervous System Tumors (CNST) from 1995 to 2014 were compared. RESULTS: Two thousand two hundred and eighty-seven AT (1 356 men and 931 women) were analyzed. The most common glioma was glioblastoma multiforme (GBM), found in young adults with a higher frequency to that reported in other studies. Relation of AT/SD, as well as, relation of AT/CNST was similar between 1995 and 2014. CONCLUSIONS: In general, the frequency of AT worldwide, being higher in the subgroup of young adults with GBM. There was not significant variation in the frequency of AT during the time studied.

OBJETIVO: Determinar distribución, localización y cambios de la frecuencia de tumores astrocíticos (TA) en un instituto mexicano de neurología. MATERIAL Y MÉTODOS: Se revisaron los registros institucionales de TA de cinco décadas. Se compararon las relaciones TA/egresos quirúrgicos (EQ) y TA/total de tumores del sistema nervioso central (TSNC) de 1995 a 2014. RESULTADOS: Se analizaron 2 287 TA (1 356 en hombres y 931 en mujeres). El glioma más común fue el glioblastoma multiforme (GBM), que estuvo presente en adultos jóvenes con una frecuencia mayor a la reportada en otros estudios. La relación TA/EQ y TA/TNSC fue similar entre 1995 y 2014. CONCLUSIONES: En general, la frecuencia de TA atendidos en el Instituto es similar a la reportada internacionalmente. No obstante, los casos de TA en el subgrupo de adultos jóvenes con GBM son más frecuentes (40%) que las incidencias reportadas en otros estudios (menores al 5%). No se encontró variación significativa en la frecuencia de TA durante las últimas dos décadas.

Immunomodulatory Effects Mediated by Dopamine.

Dopamine (DA), a neurotransmitter in the central nervous system (CNS), has modulatory functions at the systemic level. The peripheral and central nervous systems have independent dopaminergic system (DAS) that share mechanisms and molecular machinery. In the past century, experimental evidence has accumulated on the proteins knowledge that is involved in the synthesis, reuptake, and transportation of DA in leukocytes and the differential expression of the D1-like (D1R and D5R) and D2-like receptors (D2R, D3R, and D4R). The expression of these components depends on the state of cellular activation and the concentration and time of exposure to DA. Receptors that are expressed in leukocytes are linked to signaling pathways that are mediated by changes in cAMP concentration, which in turn triggers changes in phenotype and cellular function. According to the leukocyte lineage, the effects of DA are associated with such processes as respiratory burst, cytokine and antibody secretion, chemotaxis, apoptosis, and cytotoxicity. In clinical conditions such as schizophrenia, Parkinson disease, Tourette syndrome, and multiple sclerosis (MS), there are evident alterations during immune responses in leukocytes, in which changes in DA receptor density have been observed. Several groups have proposed that these findings are useful in establishing clinical status and clinical markers.

IL-8 and IL-6 primarily mediate the inflammatory response in fibromyalgia patients.

Fibromyalgia (FM) is a chronic disease that has been linked to inflammatory reactions and changes in the systemic levels of proinflammatory cytokines that modulate responses in the sympathetic nervous system and hypothalamic-pituitary-adrenal axis. We found that concentrations of IL-6 and IL-8 were elevated in FM patients. Both cytokines correlated with clinical scores, suggesting that IL-6 and IL-8 have additive or synergistic effects in perpetuating the chronic pain in FM patients. These findings indicate that IL-6 and IL-8 are two of the most constant inflammatory mediators in FM and that their levels correlate significantly with the severity of symptoms.

Chronic deep brain stimulation of the hypothalamic nucleus in wistar rats alters circulatory levels of corticosterone and proinflammatory cytokines.

Deep brain stimulation (DBS) is a therapeutic option for several diseases, but its effects on HPA axis activity and systemic inflammation are unknown. This study aimed to detect circulatory variations of corticosterone and cytokines levels in Wistar rats, after 21 days of DBS-at the ventrolateral part of the ventromedial hypothalamic nucleus (VMHvl), unilateral cervical vagotomy (UCVgX), or UCVgX plus DBS. We included the respective control (C) and sham (S) groups (n = 6 rats per group). DBS treated rats had higher levels of TNF-α (120%; P < 0.01) and IFN-γ (305%; P < 0.001) but lower corticosterone concentration (48%; P < 0.001) than C and S. UCVgX animals showed increased corticosterone levels (154%; P < 0.001) versus C and S. UCVgX plus DBS increased IL-1ß (402%; P < 0.001), IL-6 (160%; P < 0.001), and corsticosterone (178%; P < 0.001 versus 48%; P < 0.001) compared with the C and S groups. Chronic DBS at VMHvl induced a systemic inflammatory response accompanied by a decrease of HPA axis function. UCVgX rats experienced HPA axis hyperactivity as result of vagus nerve injury; however, DBS was unable to block the HPA axis hyperactivity induced by unilateral cervical vagotomy. Further studies are necessary to explore these findings and their clinical implication.

Multiple sclerosis in Caucasians and Latino Americans.

Epidemiological and genetic studies suggest that the prevalence, median age of onset, and specific phenotypes of multiple sclerosis (MS) are different in Caucasians and Latino Americans. Recent epidemiological studies indicate an increase in MS prevalence in Latin America (LA), where the south-north gradient of latitude described for Nordic countries does not exist. Analysis of MS epidemiological and specific aspects in LA suggests that susceptibility and clinical behavior of the disease are related to mixtures and admixtures of genes in the population. MS is not present in Amerindians with Mongoloid genes, such as occurs in other pure ethnic groups. Surely, future studies will be carried out to obtain more reliable information. In this review, we contrast and analyze the available data of MS in LA and endemic countries.