Regulation of the Tpo, Tg, Duox2, Pds, and Mct8 genes involved in the synthesis of thyroid hormones after subchronic exposure to sodium nitrate in female Wistar rats.

Nitrates are natural compounds present in soil and water; however, the intense use of fertilizers has increased their presence in groundwater with deleterious effects on human health. There is evidence of nitrates acting as endocrine disruptors; however, the underlying molecular mechanisms have not been fully described. Here, we investigated the effect of subchronic exposure to different concentrations of sodium nitrate in female Wistar rats, evaluating thyroid hormonal parameters, such as Nis transporter (Na+ /I- symporter, Slc5a5) and Tsh-R receptor protein expression, as well as transcription of the Tpo (thyroperoxidase), Tg (tiroglobulin), Duox2 (dual oxidase 2), Pds (pendrin), and Mct8 (Mct8 transporter, Slc16a2) genes. Hematological and histochemical changes in the liver and thyroid were also explored. Significant differences were found in platelet and leukocyte counts; although a significant increase in the weight of the thyroid gland was observed, no differences were found in the levels of the hormones Tsh, T3, and T4, but a modulation of the mRNA expression of the Tg, Tpo, Duox2, Mct8, and Pds genes was observed. Morphological changes were also found in liver and thyroid tissue according to the exposure doses. In conclusion, subchronic exposure to sodium nitrate induces leukocytosis consistent with an inflammatory response and upregulation of Sod2 in the liver and increases the expression of genes involved in the synthesis of thyroid hormones, keeping thyroid hormone levels stable. Histological changes in the thyroid gland suggest a goitrogenic effect.

Hydrocephalus in Mexican children with Coccidioidal Meningitis: Clinical, serological, and neuroimaging findings.

BACKGROUND: Coccidioidal meningitis (CM) is a fungal infectious disease that rarely affects children. Even in endemic areas, coccidiomycosis rarely affects the pediatric population. However, 40% of affected children develop hydrocephalus. Here, we describe the clinical, serological, and neuroimaging findings in a series of Mexican children admitted to our neurosurgical service with hydrocephalus and subsequently diagnosed with CM. METHODS: We report a prospective series of pediatric patients with hydrocephalus secondary to CM in an endemic area at the north of Mexico. Our report includes children with CM who were hospitalized from 2015 to 2019 in a regional hospital in Torreón, Coahuila. Clinical evolution was monitored for 1 year after hospital discharge. RESULTS: Our series include five children with CM (2-17-years-old, three female), who were hospitalized for hydrocephalus and developed intracranial hypertension. The most frequent neuroimaging findings were leptomeningeal enhancement (5/5) and basal arachnoiditis (4/5), followed by asymmetric hydrocephalus (3/5), abnormalities in fourth ventricle morphology (3/5), and cerebral vasculitis (2/5). CM was diagnosed by positive serology or pathology studies. All children were initially managed with fluconazole and a shunt was placed for management of hydrocephalus. Four patients recovered without permanent neurological deficits and one subject developed persistent vegetative state. One year after hospital discharge, none of the subjects died. CONCLUSION: This series contributes to the limited number of pediatric CM cases reported in the literature, and describes neuroimaging findings in the pediatric population. The cases here presented show that the identification of Coccidioides as causal agent in pediatric meningitis is crucial for targeted treatment and can affect dramatically neurological prognosis. Furthermore, our report stresses that even in endemic areas pediatric coccidiomycosis represents a diagnostic challenge, which is further exacerbated by the limited availability of resources in these regions. Therefore, a positive immunoglobulin G by enzyme immunoassay is enough for diagnosis of CM in endemic areas without access to CF.