Clinical and microbiological evaluation of the effect of Lactobacillus reuteri in the treatment of mucositis and peri-implantitis: A triple-blind randomized clinical trial.

BACKGROUND AND OBJECTIVE: Oral probiotics appear to improve the treatment of periodontal diseases but there is limited evidence on their efficacy in the treatment of peri-implant diseases. The objective of the present study was to evaluate, clinically and microbiologically, the effect of the oral probiotic, Lactobacillus reuteri Prodentis, as adjuvant to non-surgical mechanical therapy in implants with mucositis or peri-implantitis, placed in patients with a history of periodontal disease. MATERIAL AND METHODS: A randomized, controlled, parallel-design, triple-blind prospective clinical study was designed. Patients included in the study were partially edentulous and had implants with mucositis or peri-implantitis. Implants with radiographic bone loss of ≥5 mm and/or ≥50% of the implant length were excluded, and only one implant per patient was included. After non-surgical mechanical therapy, subjects were randomly assigned to take either 1 probiotic lozenge or 1 placebo lozenge every day for 30 days. Clinical measurements were taken in the whole mouth (general plaque index and general bleeding on probing) and at the implant site (probing pocket depth, plaque index and bleeding on probing) at baseline and 30 and 90 days Microbiological examination (to identify Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Campylobacter rectus and Eikenella corrodens) was performed at the same study time points that clinical measurements were made. RESULTS: A total of 44 patients - 22 with mucositis and 22 with peri-implantitis - randomly received treatment with either probiotic or placebo. The probiotic L. reuteri, together with mechanical therapy, produced an additional improvement over treatment with mechanical therapy alone, both in the general clinical parameters of patients with mucositis (bleeding on probing) and at the level of implants with mucositis (probing pocket depth) or peri-implantitis (bleeding on probing and probing pocket depth). However, L. reuteri had a very limited effect on the peri-implant microbiota because the only parameter in which a significant decrease was found was the bacterial load of P. gingivalis in implants with mucositis (P = .031). CONCLUSION: The administration of a daily lozenge of L. reuteri for 30 days, together with mechanical debridement of the whole mouth, improved the clinical parameters of implants with mucositis or peri-implantitis over a period of at least 90 days, but the microbiological effect was much more limited. Probiotics provide an alternative therapeutic approach to consider in the prevention and treatment of peri-implant diseases, but further long-term prospective studies with standardized variables are needed.

Therapeutic antidepressant potential of a conjugated siRNA silencing the serotonin transporter after intranasal administration.

Major depression brings about a heavy socio-economic burden worldwide due to its high prevalence and the low efficacy of antidepressant drugs, mostly inhibiting the serotonin transporter (SERT). As a result, ~80% of patients show recurrent or chronic depression, resulting in a poor quality of life and increased suicide risk. RNA interference (RNAi) strategies have been preliminarily used to evoke antidepressant-like responses in experimental animals. However, the main limitation for the medical use of RNAi is the extreme difficulty to deliver oligonucleotides to selected neurons/systems in the mammalian brain. Here we show that the intranasal administration of a sertraline-conjugated small interfering RNA (C-SERT-siRNA) silenced SERT expression/function and evoked fast antidepressant-like responses in mice. After crossing the permeable olfactory epithelium, the sertraline-conjugated-siRNA was internalized and transported to serotonin cell bodies by deep Rab-7-associated endomembrane vesicles. Seven-day C-SERT-siRNA evoked similar or more marked responses than 28-day fluoxetine treatment. Hence, C-SERT-siRNA (i) downregulated 5-HT1A-autoreceptors and facilitated forebrain serotonin neurotransmission, (ii) accelerated the proliferation of neuronal precursors and (iii) increased hippocampal complexity and plasticity. Further, short-term C-SERT-siRNA reversed depressive-like behaviors in corticosterone-treated mice. The present results show the feasibility of evoking antidepressant-like responses by selectively targeting neuronal populations with appropriate siRNA strategies, opening a way for further translational studies.

Studies with neuronal cells: From basic studies of mechanisms of neurotoxicity to the prediction of chemical toxicity.

Neurotoxicology considers that chemicals perturb neurological functions by interfering with the structure or function of neural pathways, circuits and systems. Using in vitro methods for neurotoxicity studies should include evaluation of specific targets for the functionalism of the nervous system and general cellular targets. In this review we present the neuronal characteristics of primary cultures of cortical neurons and of cerebellar granule cells and their use in neurotoxicity studies. Primary cultures of cortical neurons are constituted by around 40% of GABAergic neurons, whereas primary cultures of cerebellar granule cells are mainly constituted by glutamatergic neurons. Both cultures express functional GABAA and ionotropic glutamate receptors. We present neurotoxicity studies performed in these cell cultures, where specific neural targets related to GABA and glutamate neurotransmission are evaluated. The effects of convulsant polychlorocycloalkane pesticides on the GABAA, glycine and NMDA receptors points to the GABAA receptor as the neural target that accounts for their in vivo acute toxicity, whereas NMDA disturbance might be relevant for long-term toxicity. Several compounds from a list of reference compounds, whose severe human poisoning result in convulsions, inhibited the GABAA receptor. We also present cell proteomic studies showing that the neurotoxic contaminant methylmercury affect mitochondrial proteins. We conclude that the in vitro assays that have been developed can be useful for their inclusion in an in vitro test battery to predict human toxicity.

[Isotopic study with double phase 99mTc-sestamibi in the localization of parathyroid gland lesions]. / Exploración isotópica con 99mTc-sestamibi en doble fase en la localización de lesiones de las glándulas paratiroides.

BACKGROUND: The use of preoperative imaging in patients with hyperparathyroidism remains controversial. The aim of this study is to assess the usefulness of the double-phase 99mTc-sestamibi scintigraphy in the diagnosis of abnormal parathyroid glands in patients with primary hyperparathyroidism. PATIENTS AND METHODS: We studied 60 patients presenting with primary hyperparathyroidism who were referred to surgery; four of them had been unsuccessfully operated. 99mTc-sestamibi scintigraphy were performed in all patients previously to surgery. Scintigraphic technique: planar imaging of the neck and thorax was done in the anterior view at 15 and 150 min postinjection of 740 MBq (20 mCi) of 99mTc-sestamibi. RESULTS: Surgery found 57 adenomas (2.59 [SD, 5.84] g; range 0.160-40), 6 hyperplastic glands (0.34 [SD, 0.26] g) and one carcinoma 8.2 g. The 99mTc-sestamibi was able to localize correctly 60 out of 64 lesions (55/57 adenomas, 4/6 hyperplastic glands and 1/1 carcinoma) (global sensitivity of 94%, adenomas sensitivity of 96%, positive predictive value of 97% and specificity of 98%). Isotopic imaging detected the abnormal tissue in all patients who had undergone unsuccessful previous surgery. PTH (4 [SD, 1.51] pmol/l) and calcium postoperative serum levels (2.13 [SD, 0.22] mmol/l) showed curation of all patients. CONCLUSION: Double phase parathyroid scintigraphy with 99mTc-sestamibi is the method of choice to localize abnormal parathyroid glands.

[Zenker's diverticulum. The clinical manifestations and treatment]. / Diverticulo de Zenker. Manifestaciones clínicas y tratamiento.

Clinical manifestations and surgical results are analyzed in a retrospective study of 16 patients with a Zenker's diverticulum. Pharyngoesophageal diverticulum are an uncommon anomaly, producing cervical dysphagia and recurrent airway infections. Treatment should be surgical, as earliest as possible. Morbidity is very low and mortality very rare.