Early life GABAA blockade alters the synaptic plasticity and cognitive functions in male and female rats

Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in adults, has a critical contribution to balanced excitatory-inhibitory networks in the brain. Alteration in depolarizing action of GABA during early life is connected to a wide variety of neurodevelopmental disorders. Additionally, the effects of postnatal GABA blockade on neuronal synaptic plasticity are not known and therefore, we set out to determine whether postnatal exposure to bicuculline, a competitive antagonist of GABA_A receptors, affects electrophysiologic changes in hippocampal CA1 neurons later on. To this end, male and female Wistar rats received vehicle or bicuculline (300 μg/kg) on postnatal days (PNDs) 7, 9 and 11, and then underwent different behavioral and electrophysiological examinations in adulthood. Postnatal exposure to bicuculline did not affect basic synaptic transmission but led to a pronounced decrease in paired-pulse facilitation (PPF) in CA1 pyramidal neurons. Bicuculline treatment also attenuated the long-term potentiation (LTP) and long-term depression (LTD) of CA1 neurons accompanied by decreased theta-burst responses in male and female adult rats. These electrophysiology findings together with the reduced brain-derived neurotrophic factor (BDNF) levels in the hippocampus and prefrontal cortex reliably explain the disturbance in spatial reference and working memories of bicuculline-treated animals. This study suggests that postnatal GABA_A blockade deteriorates short- and long-term synaptic plasticity of hippocampal CA1 neurons and related encoding of spatial memory in adulthood.

Neonatal NMDA blockade alters the LTP, LTD and cognitive functions in male and female Wistar rats

There is compelling evidence that neonatal blockade of NMDA receptors by phencyclidine (PCP) is associated with cognitive impairment in adulthood but little is known about the effects of early life PCP treatment on synaptic function later in life. Here, we sought to determine whether early life exposure to PCP alters the electrophysiologic function of hippocampal CA1 neurons in adult rats. To this end, male and female Wistar rats received either saline or PCP (10 mg/kg) on postnatal days (PND) 7, 9, and 11, and then underwent separate behavioral and electrophysiology tests in adulthood. Neonatal PCP treatment did not alter basic synaptic transmission and had only a modest effect on frequency following (FF) capacity but significantly decreased the paired-pulse facilitation (PPF) in the Schaffer collateral (SC)-CA1 pathway. We found that PCP treatment significantly attenuated the long-term potentiation (LTP) and long-term depression (LTD) in CA1 neurons accompanied by pronounced alteration in complex response profile in adult rats. The electrophysiology data were comparable in male and female rats and reliably associated with impaired spatial reference and working memories in these animals. Overall, this study suggests that blockade of NMDA receptors during early life deteriorates the short-term and long-term synaptic plasticity and complex response profile of CA1 neurons in adulthood.

Opium tincture for opioid substitution treatment

Introduction

Opium tincture (OT) is widely used for opioid substitution treatment (OST) in Iran.

Objectives

To determine if OT is a safe and effective medication for OST.

Methods

Opium Trial was a multicenter, double‐blind, noninferiority randomized controlled trial, with 204 participants with opioid dependence in Iran. Participants were then randomized to OT or methadone arms with an allocation ratio of 1:1 and were followed for 12 weeks. The primary outcome was retention in treatment, compared between the two groups using both intention-To-Treat (ITT) and Per-Protocol (PP) analyses.

Results

A total of 70 participants (IT: 68.6%, PP: 69.3%) in methadone arm and 61 participants (ITT: 59.8%, PP: 60.4%) in OT arm remained in the treatment. The relative retention rate was 1.15 (0.97, 1.36) in both analyses in favour of methadone. A total of 46 out of 152 (30.3%) participants in OT arm and 83 out of 168 (49.4%) participants in methadone arm reported opioid use outside the treatment. The difference in these two proportions (OT - methadone) was 19%: (10%, 28%) in favour of OT. The proportion of patients with adverse events were not different between the two arms (P = 0.06). There was no serious AE in OT arm.

Conclusions

Opium tincture is a clinically effective and safe medication, but this study could not conclude if it was as equally effective as methadone in retaining participants in treatment, but it showed that OT was superior to methadone in reducing opioid use outside the treatment.

Disclosure

No significant relationships.

Flavanols are potential anti-obesity agents, a systematic review and meta-analysis of controlled clinical trials

BACKGROUND

The anti-obesity potential of flavonoids has been shown by animal and human studies. In this meta-analysis, we systematically reviewed controlled clinical trials and quantified the effects of flavonoids and flavonoid subclasses on obesity-related anthropometric measures.

METHODS AND RESULTS

PubMed, EMBASE, Scopus, Web of Science, and ProQuest databases were searched to identify trials examining the effect of flavonoids on body mass index (BMI), waist circumference, and body fat percentage. Fifty eight trials passed the eligibility process. Analysis endpoints were calculated as the mean difference between baseline and post-treatment. Flavonoids were in subclasses of flavanols, flavonols, isoflavones, flavanones, anthocyanins, and proanthocyanidins. They were mostly in the form of supplements and dosages varying from 40 to 1300 mg/day. Among flavonoid subclasses, flavanols showed potential for decreasing BMI, in the overall population (mean difference (MD) = -0.28 kg/m², P = 0.04; n = 21) and in the subgroups of Asians (MD = -0.42 kg/m²; P = 0.046; n = 13), ages < 50 years (MD = -0.50 kg/m²; P = 0.008; n = 14), BMI ≥ 25 kg/m² (MD = -0.30 kg/m²; P = 0.049; n = 15), and at doses ≥ 500 mg/day (MD = -0.36 kg/m²; P = 0.049; n = 12). Isoflavones also decreased BMI of non-Asian populations (MD = -0.26 kg/m²; P = 0.035; n = 13) and doses ≥ 75 mg/day (MD = -0.34 kg/m²; P = 0.027; n = 8). In the overall assessment, flavanols also decreased waist circumference (MD = -0.60 cm; P = 0.02; n = 18) but had no significant effect on body fat percentage. The available trials did not reveal significant effects from flavonols, flavanones, and anthocyanins on the specified anthropometric measures.

CONCLUSIONS

Overall results of this meta-analysis showed that flavanols have potential against obesity.

Inner ear drug delivery using liposomes

Dysfunction of inner ear can result in from several disease procedures and introduce a possibility for therapeutic intervention. The existence of a blood-cochlear obstacle and round window membrane restricts direct access into the inner ear and following inner ear drug, gene, protein and cell delivery. Several strategies have designed to increase drug delivery to the inner ear. One of main particles for inner ear drug delivery is liposome. Here we reviewed the application of liposomes in inner ear drug delivery.

Evaluation of anti-toxoplasma IgG, IgM, and IgA in mothers with spontaneous abortion in Zanjan, Northwest Iran

Toxoplasma gondii is one of the major agents of infectious abortions and due to its worldwide distribution can threat healthy pregnant women who had no previous exposure to this parasite. The present study was designed to investigate the contribution of T. gondii to spontaneous abortions in Zanjan, Northwest of Iran, using ELISA method. Blood Samples were collected from 264 mothers referred to the provincial hospitals of Zanjan due to spontaneous abortion. The sera were isolated and subjected to evaluate the anti-Toxoplasma IgG, IgM and IgA antibodies. The results showed IgG positive (IgG(+)) in 99 cases (37.5%). A total of 68 women (25.8%) showed seroconversion with IgM or IgA or both IgM and IgA. They included: IgM(+) in 21 (8.0%), IgA(+) in 23 (8.7%) and both IgM(+) and IgA(+) in 24 (9.1%) subjects. In 23 cases, positive titers of IgM and IgG were accompanied. In general, the analysis of anti-Toxoplasma antibody patterns, showed that about 17% of the spontaneous abortions were associated with serological patterns of acute infection. According to these findings, a considerable proportion of spontaneous abortions can be attributed to T. gondii in the study area.

Spontaneous recanalization of the occluded internal carotid artery. A report of two cases

Spontaneous recanalization of the occluded internal carotid artery (ICA) is more frequent than is generally believed. The timing of spontaneous recanalization remains unclear but it may occur as either an early or a late event. The aim of this case report is to emphasize the importance of spontaneous recanalization and its consequences. From September 2008 to November 2010 we prospectively followed patients with old ICA occlusion. The diagnoses of an occlusion were based on duplex scan findings and were confirmed by CT angiography and digital subtraction angiography (DSA). ICA occlusions secondary to dissection, inflammatory process, like fibromuscular dysplasia, previous stenting or endarterectomy and trauma, were excluded from the study. All patients had a scheduled carotid duplex scan every six months. Overall 65 patients were enrolled. Two patients showed evidence of spontaneous recanalization. A 55-year-old man with a known history of transient ischemic attack had occlusion in the left side ICA. He presented with another TIA eight months later. Investigations showed evidence of rcanalization of occluded ICA. This artery underwent uneventful stenting. In another patient recanalization was heralded by global aphasia and right side hemiplegia. He was a 70-year-old man with a history of recurrent TIA. Carotid duplex scan and DSA showed recanalization of the occluded left ICA accompanied by occlusion of the ipsilateral middle cerebral artery. He remained profoundly disabled with severe neurological deficits. In conclusion, spontaneous recanalization of the occluded internal carotid artery is a potentially complicated event that may lead to severe neurological disability.

Treatment of progressive cerebral sinuses thrombosis with local thrombolysis

Cerebral venous thrombosis (CVT) is a potentially serious disease, with nonspecific clinical symptoms and an unpredictable outcome. Despite adequate anticoagulation, a patient's clinical condition can rapidly deteriorate. The aim of this study was to evaluate the efficacy of local thrombolysis in these patients. Consecutive patients with progressive cerebral venous thrombosis between October 2008 and January 2011 were enrolled prospectively. Progressive CVT was defined as the persistence of neurologic findings (headache, blurred vision, and visual field defects) despite at least four days (or 48 hours in patients with involvement of more than one sinus) on full anticoagulation therapy with heparin and development of focal neurologic deficits or cortical hemorrhage. We excluded patients with large hematomas and predisposing malignancies like leukemia. All patients underwent local thrombolysis with 30 mg recombinant tissue plasminogen activator (rtPA). Overall, 26 patients were enrolled with a mean age of 35.5 years (range 18 to 56 years). Six patients (23%) were male and twenty patients (77%) were female. The most common presenting feature was headache and the most common neurologic finding was papilledema, which was present in all patients. Eighty-five percent of women had a history of oral contraceptive pill consumption. Successful recanalization was achieved in all patients except one (96.2%). Neurological examinations and follow-up assessments were based on a modified Rankin scale (mRS). Favorable outcome and recovery was defined as a mRS score of 0-1. Follow-up assessments at the third week showed that 25 out of 26 recovered, with 18 having a mRS score of 0 and 7 with a mRS score of 1. There were no procedure-related neurological complications. Our results show that local thrombolysis is a safe and effective treatment modality for patients suffering from progressive CVT.

Vertebral artery orifice stenosis: a report of 43 cases from northwest iran treated with angioplasty and stenting

More than one quarter of all transient ischemic attacks (TIA's) and ischemic strokes involve tissue supplied by the vertebrobasilar (VB) circulation. Vertebral artery stenotic lesion, particularly at the origin of the vertebral artery, is not uncommon but it is a less studied area. Here we present our endovascular treatment experience in a group of patients with vertebral artery orifice stenosis. We enrolled a group of patients with vertebral artery orifice stenosis who presented with confirmed posterior circulation stroke. Vertebrobasilar insufficiency syndrome was confirmed by imaging studies and clinical findings. Vertebral artery stenosis diagnosed by CT or MR Angiography and confirmed by Conventional and digital subtraction angiography (DSA). Angiography was performed by using of femoral or radial artery approach. From October 2008 to January 2010, forty-three consecutive patients (69.8% men) underwent stent placement for symptomatic vertebral artery orifice stenosis. Mean degree of stenosis was 70.45 +/- 7.455 percent and mean age was 71.65 +/- 7.743 years . In the 22 patients (22/43, 51.16%) stenosis were in left side. In the thirty patients (30/43, 69.6%) there was evidence of atherosclerotic disease in the internal carotid artery and in the 23% contra lateral vertebral artery was involved. There were five different cases with left renal artery stenosis especially in the men with left vertebral artery stenosis. Initial technical success rate was 100%. No cerebrovascular complications or embolic events occurred. Six months control angiography follow-up revealed one patient with stent occlusion and moderate (40%) restenosis in the another patient. According to our finding angioplasty and stenting for vertebral artery orifice stenosis is safe and effective. Patients with vertebral artery orifice disease frequently have coexistent atherosclerotic stenosis in the other major extracranial arteries including carotid and renal arteries.