[Patients with anti-GABA (B) receptor encephalitis: 8 cases report].

Objective: To discuss the clinical features, diagnosis, therapy and prognosis of anti-GABA (B) receptor encephalitis. Methods: Clinical data of patients with anti-gaba B receptor encephalitis admitted to the department of neurology of the second hospital of hebei medical university from April 2016 to February 2018 were collected and retrospectively analyzed. Results: Eight patients with anti-GABA (B) receptor encephalitis were included. All the eight cases presented with epileptic seizures. The initial symptoms were clinical seizures in six cases, memory deficit in one case, mental and behavior disorder in one case. Cerebrospinal fluid (CSF) test indicated high intracranial pressure in four patients, increased protein in two patients and lymphocytosis in four patients. Long-term electroencephalogram (EEG) showed abnormal in all patients. Brain MRI showed limbic system lesions in four patients. The anti-GABA (B) receptor antibody was positive in both serum and CSF in all patients. Four patients had small cell lung cancer. All the eight patients received immunotherapy and symptoms were improved. After 6-24 months' follow-up, 1 patient recovered completely, and in the remaining 7 patients, mild symptoms were left behind. Conclusions: The anti-GABA (B) receptor encephalitis is characterized by refractory epilepsy. Epilepsy is the most common initial symptom. About 50% patients are accompanied by tumors. Anti-GABA (B) receptor antibodies testing and tumor screening should be actively carried out.

From Nitrate to Nitric Oxide: The Role of Salivary Glands and Oral Bacteria.

The salivary glands and oral bacteria play an essential role in the conversion process from nitrate (NO3-) and nitrite (NO2-) to nitric oxide (NO) in the human body. NO is, at present, recognized as a multifarious messenger molecule with important vascular and metabolic functions. Besides the endogenous L-arginine pathway, which is catalyzed by complex NO synthases, nitrate in food contributes to the main extrinsic generation of NO through a series of sequential steps (NO3--NO2--NO pathway). Up to 25% of nitrate in circulation is actively taken up by the salivary glands, and as a result, its concentration in saliva can increase 10- to 20-fold. However, the mechanism has not been clearly illustrated until recently, when sialin was identified as an electrogenic 2NO3-/H+ transporter in the plasma membrane of salivary acinar cells. Subsequently, the oral bacterial species located at the posterior part of the tongue reduce nitrate to nitrite, as catalyzed by nitrate reductase enzymes. These bacteria use nitrate and nitrite as final electron acceptors in their respiration and meanwhile help the host to convert nitrate to NO as the first step. This review describes the role of salivary glands and oral bacteria in the metabolism of nitrate and in the maintenance of NO homeostasis. The potential therapeutic applications of oral inorganic nitrate and nitrite are also discussed.