Immunofluorescently labeling glutamic acid decarboxylase 65 coupled with confocal imaging for identifying GABAergic somata in the rat dentate gyrus—A comparison with labeling glutamic acid decarboxylase 67

As γ-aminobutyric acid (GABA) is synthesized by two isoforms of glutamic acid decarboxylase (GAD), namely, GAD₆₅ and GAD₆₇, immunohistochemically targeting either isoform of GAD is theoretically useful for identifying GABAergic cell bodies. In practice, targeting GAD₆₇ remains to be a popular choice. However, identifying GABAergic cell bodies with GAD₆₇ immunoreactivity in the hippocampal dentate gyrus, especially in the hilus, is not without pitfalls. In the present study, we compared the characteristics of GAD₆₅ immunoreactivity to GAD₆₇ immunoreactivity in the rat dentate gyrus and examined perikaryal expression of GAD₆₅ in four neurochemically prevalent subgroups of interneurons in the hilus.Experiments were done in normal adult Sprague-Dawley rats and GAD₆₇-GFP knock-in mice. Horizontal hippocampal slices cut from the ventral portion of hippocampi were immunofluorescently stained and scanned using a confocal microscope. Immunoreactivity for both GAD₆₇ and GAD₆₅ was visible throughout the dentate gyrus. Perikaryal GAD₆₇ immunoreactivity was denser but variable in terms of distribution pattern and intensity among cells whereas perikaryal GAD₆₅ immunoreactivity displayed similar distribution pattern and staining intensity. Among different layers of the dentate gyrus, GAD₆₇ immunoreactivity was densest in the hilus despite GAD₆₅ immunoreactivity being more intense in the granule cell layer. Co-localization experiments showed that GAD₆₅, but not GAD₆₇, was expressed in all hilar calretinin (CR)-, neuronal nitric oxide synthase (nNOS)-, parvalbumin (PV)- or somatostatin (SOM)-positive somata. Labeling CR, nNOS, PV, and SOM in sections obtained from GAD₆₇-GFP knock-in mice revealed that a large portion of SOM-positive cells had weak GFP expression. In addition, double labeling of GAD₆₅/GABA and GAD₆₇/GABA showed that nearly all of GABA-immunoreactive cells had perikaryal GAD₆₅ expression whereas more than one-tenth of GABA-immunoreactive cells lacked perikaryal GAD₆₇ immunoreactivity. Inhibition of axonal transport with colchicine dramatically improved perikaryal GAD₆₅ immunoreactivity in GABAergic cells without significant augmentation to be seen in granule cells. Double labeling GAD₆₅ and GAD₆₇ in the sections obtained from colchicine-pretreated animals confirmed that a portion of GAD₆₅-immunoreactive cells had weak or even no GAD₆₇ immunoreactivity.We conclude that for confocal imaging, immunofluorescently labeling GAD₆₅ for identifying GABAergic somata in the hilus of the dentate gyrus has advantages over labeling GAD₆₇ in terms of easier recognition of perikaryal labeling and more consistent expression in GABAergic somata. Inhibition of axonal transport with colchicine further improves perikaryal GAD₆₅ labeling, making GABAergic cells more distinguishable.     

Ischemic tolerance induction in organotypic hippocampal slices: role for the GABA(A) receptor?

Ischemic preconditioning (IPC) refers to sublethal ischemic insults rendering brain tissue tolerant against subsequent ischemic insults. We investigated the role of the GABA(A) receptor (GABA(A)R) upon IPC induction. Rat organotypic hippocampal slices were subjected to IPC by 15 min of oxygen-glucose deprivation (OGD) followed by 40 min of OGD 48 h later, resulting in robust cell death reduction as assessed by the propidium iodide fluorescence method ('late' or 'second window' IPC). Superfusion with the GABA(A)R antagonist bicuculline during IPC ameliorated propidium iodide uptake at a high but not at low doses indicating that GABA(A)R activation may be assigned a limited role in neuroprotection. In previous studies, we found that increased neuronal excitability can promote IPC neuroprotection. We, therefore, tested the hypothesis that blockade of inhibitory GABAergic transmission conferred ischemic tolerance. However, temporary administration of bicuculline 48 h prior to ischemic challenge was not neuroprotective. In another approach, we tested whether preconditioning with the GABA(A)R agonist, 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP) mediated ischemic tolerance and found no significant neuroprotection. The results are discussed in light of the intrinsic excitatory-inhibitory balance of glutamate and GABA.     

Is there a role for fatty acid synthase in the diagnosis of prostatic adenocarcinoma?: A comparison with AMACR

Our aim was to compare the usefulness of fatty acid synthase (FASn) with that of α-methylacyl coenzyme-A racemase (AMACR) in the diagnosis of prostatic adenocarcinoma. The expression of these 2 markers was compared in a tissue microarray containing 62 foci of benign glands and 36 foci of prostatic adenocarcinoma. Similar to AMACR, there was significantly higher FASn expression in adenocarcinoma compared with that in benign glands. The optimal accuracy rate and area under curve (AUC) by receiver operating characteristic analysis for FASn were not significantly different from those for AMACR (accuracy, 80% vs 87%; AUC, 0.942 vs 0.956; P for both, > .05). Moreover, in cases with coexistent malignant and benign glands on the same core, FASn could selectively distinguish a proportion of cases (17/21 [81%]) similar to using AMACR. We conclude that FASn may aid in the diagnosis of prostatic adenocarcinoma, at least to supplement AMACR as another positive marker of carcinoma and potentially increase diagnostic accuracy.     

Hypersociability in Williams syndrome: A role for the amygdala?

We read with great interest the paper of Riby et al. regarding atypical, unfamiliar face processing in Williams syndrome (WS; Riby, Doherty-Sneddon, & Bruce, 2008a). It offers considerable insight into the mechanism of facial perception in humans and a further elaboration of the hypersociability observed in patients with Williams syndrome. We would like to suggest that the neurologic mechanisms underlying the hypersociability in WS may be attributable to an impaired recognition of facial expressions of threat, a feature that localises to the amygdala.     

Neurotoxicity associated with neuroleptic-induced oral dyskinesias in rats. Implications for tardive dyskinesia?

Tardive dyskinesia is a serious motor side effect of long-term treatment with neuroleptics, with an unknown pathophysiologic basis. Brain damage and aging are prominent risk-factors, and together with the persistent character of the disorder, it is likely that long-lasting neuronal changes are involved in the pathogenesis. It has been hypothesized that striatal neurodegeneration caused by excitotoxic mechanisms and oxidative stress may play an important role in the development of the disorder, and the scope of the present work is to review the evidence supporting this hypothesis. The rat model of tardive dyskinesia has been used extensively in the field, and the usefulness of this model will be discussed. Neuroleptics are able to induce oxidative stress in vitro and increase striatal glutamatergic activity in rats, which may lead to toxic effects in the striatum. Drugs that block excitotoxicity inhibit the development of persistent oral dyskinesia in the rat model, and impaired energy metabolism leads to increased frequency of oral dyskinesia. There are also signs of altered striatal histology in rats with high frequency of oral dyskinesia. Furthermore, markers of increased oxidative stress and glutamatergic neurotransmission have been found in the cerebrospinal fluid of patients with tardive dyskinesia. In conclusion, several lines of evidence implicate neurotoxic events in the development of neuroleptic induced tardive dyskinesia.     

Th9 cells in allergic diseases: A role for the microbiota?

Since their discovery about 10 years ago, Th9 cells have been increasingly linked to allergic pathologies. Within this review, we summarize the current knowledge on associations between Th9 cells and allergic diseases and acknowledge Th9 cells as important targets in future treatment of allergic diseases. However, until today, it is not fully understood how these Th9 cell responses are modulated. We describe current literature suggesting that these Th9 cell responses might be stimulated by microbial species such as Staphylococcus aureus and Candida albicans, while on the other hand, microbial and dietary compounds such as retinoic acid (RA), butyrate and vitamin D show suppressive capacity on allergy-related Th9 responses. By reviewing this recent research, we provide new insights into the modulating capacity of the microbiota on Th9 cell responses. Consequently, microbial and dietary factors may be used as innovative tools to target Th9 cells in the treatment of allergic diseases. However, further research is needed to elucidate the mechanisms behind these interactions in order to translate this knowledge into clinical allergy settings.     

Does pretraining spare the spatial deficit associated with anterior thalamic damage in rats?

Rats that had been pretrained on 2 tests of allocentric memory (water maze and T maze) received bilateral cytotoxic lesions in the anterior thalamic nuclei (ATN) or transection of the fimbria-fornix (FF). After surgery, both groups of rats were impaired on both tasks, although the preoperative training resulted in a rapid initial reacquisition of the water maze task. Those rats with lesions largely restricted to the ATN were impaired at a level comparable to that produced by FF lesions. This finding is consistent with a close functional relationship between the hippocampus and the ATN, necessary for the acquisition and on-line processing of allocentric spatial information but not for the maintenance/retrieval of procedural information. The rats with more extensive thalamic lesions were more impaired in both tasks and did show a loss of procedural information.     

Novel findings in the cephalic phase of digestion: A role for microcirculation?

The cephalic phase of digestion (CPD) has been extensively investigated in terms of digestion and metabolism. Nevertheless, microcirculatory changes required to prepare peripheral tissues in order to dispose nutrients have never been assessed. In this study, microvascular function has been evaluated to determine its behavior and potential association to hormonal secretions during CPD. Thirty-nine healthy male subjects, 23.4 ± 0.5 years (mean ± SD) and BMI of 23.3 ± 2.3 kg/m(2), were randomized into receiving cognitive-sensorial stimuli to elicit CPD (CPD group, n=20) or not (control group, n=19), after a 12-h overnight fast. Main outcomes were differences in resting and peak functional capillary density (FCD, cap/mm(2)); resting red blood cell velocity (RBCV), peak RBCV (RBCV(max)) and time taken to reach it (TRBCV(max)); peak flow and vasomotion, before and after CPD and their associations with insulin and/or pancreatic polypeptide (PP). In the CPD group, basal FCD (24.9 ± 7.6 to 28.3 ± 8.1, p=0.005), peak FCD (27.8 ± 6.3 to 32.6 ± 7.1, p=0.002), RBCV (0.306 ± 0.031 to 0.330 ± 0.027 mm/s, p=0.005), RBCV(max) (0.336 ± 0.029 to 0.398 ± 0.292 mm/s, p=0.005) and peak flow (23.5 ± 14.3 to 26.9 ± 15.8 PU, p<0.01) increased while TRBCV(max) decreased (4.9 ± 1.5 to 3.5 ± 1.2s, p=0.01). No significant changes could be detected in the control group. Groups have not presented differences for insulin, but PP significantly increased in the CPD group and was positively associated to basal FCD increase (rho=0.527, p=0.03). In conclusion, neurally-mediated anticipatory responses of digestion elicited functional capillary recruitment associated to PP in healthy men, suggesting a precocious role for microcirculation in the physiology of digestion and nutrient homeostasis.     

Which complement assays and typings are necessary for the diagnosis of complement deficiency in patients with lupus erythematosus? A study of 25 patients

INTRODUCTION: Deficiencies in components of the classical pathway of complement activation are strong risk factors for lupus erythematosus (LE).Yet, it has not been addressed whether the conventional measurements of the serum hemolytic CH50 activity and antigenic concentrations of C3 and C4 are sufficient to asses a deficiency in C4A, C4B or C2 components, the most common deficiencies associated with LE. PATIENTS AND METHODS: In a retrospective series, we performed complement analyses in 35 patients with LE who were systematically screened for a complement deficiency. The majority of patients had cutaneous LE with mild systemic involvement and no complement consumption. Of 25 patients (72%) with complement deficiency we found 13 with a partial C4A deficiency, 2 with a complete C4A deficiency, 6 with a partial C4B deficiency, 2 with a complete C4B deficiency and 2 with a combined partial C2 and C4A deficiency. RESULTS: The total complement activity (CH50) was decreased in only one out of two patients with complete C4B deficiency. CH50 level was found to be low-normal (35-38 U/ml(-1)) in one patient with partial C4B deficiency, one patient with complete C4B deficiency and both patients with combined partial C4A and C2 deficiency. Total C4 levels were normal in 9 out of 13 the patients with a partial C4A deficiency and in 2 out of 6 patients with a complete C4B deficiency. The antigenic concentration of C3 was low in only 1 patients with a complete C4B deficiency and within the normal range in all the others patients. Overall, 50% of the patients had normal or elevated C3, C4, and CH50 levels. DISCUSSION: This study emphasizes that the usual measurements of CH50, C3 and C4 levels are not adequate to detect a C4 and/or C2 deficiency in patients with LE. In epidemiologic or investigative studies addressing the prevalence of complement deficiency, more elaborated diagnostic tests, such as C4 protein allotyping, C2 level measurement and genetic screening for type I C2 deficiency should also be performed.     

Pentylenetetrazol kindling in rats: Is neurodegeneration associated with manifestations of convulsive activity?

Structural changes in neurons and measures of oxidative stress were studied in the hippocampus of rats tolerant (ST) and sensitive (SS) to developing clonic-tonic seizures in conditions of pentylenetetrazol kindling. Sequences of 11 injections of pentylenetetrazol significantly decreased the number of normal neurons in hippocampal field CA1 in SS rats, this effect being seen in both hippocampal field CA1 and the dentate fascia in ST rats. Decreases in the numbers of normal neurons were accompanied by increases in the numbers of damaged cells in field CA4 in rats of both groups. After 21 injections, decreases in the numbers of normal neurons were seen in field CA1 in both SS and ST rats, while the numbers of damaged neurons were significantly greater than control only in ST rats in fields CA1 and CA4. The glutathione level was significantly lower in the hippocampus in both groups of rats than in controls. Thus, rats “ tolerant” to developing convulsions show signs of oxidative stress and neurodegenerative changes in the hippocampus. This suggests that oxidative neuron damage leading to neurodegeneration in the pentylenetetrazol kindling model is not directly associated with convulsive activity. __________ Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 91, No. 7, pp. 764–775, July, 2005.     

NKRP1A+ γδ and αβ T cells are preferentially induced in patients with Salmonella infection

NKRP1A(+) γδ and αβ T cells play an important role at the early phase of Salmonella infection in mice. Meanwhile, association between NKRP1A(+) T cells and human Salmonella infection has not been reported. The objective of this study was to investigate the role of the peripheral NKRP1A(+) T cells in immune response to Salmonella infection. Expression of NKRP1A in peripheral γδ and αβ T cells and production of interferon (IFN) γ and interleukin (IL)-4 in NKRP1A(+) γδ and αβ T cells were analyzed in 28 patients with acute phase Salmonella infection, 23 patients with acute bacterial enterocolitis other than Salmonella infection (disease controls) and 44 normal controls by flow cytometry. The proportion of γδ T cells expressing NKRP1A and that of IFNγ-producing cells in NKRP1A(+) γδ cells were significantly higher in Salmonella group than those in other two groups. Compared with normal controls, the proportion of αβ T cells expressing NKRP1A and that of IL-4-producing cells in NKRP1A(+) αβ cells were significantly higher in Salmonella group. These data suggested that NKRP1A(+) T cells might play an important role in the early defense mechanism against Salmonella infection.     

Management of intracranial hemorrhage in patients with mechanical circulatory support: a role for low-molecular-weight heparins?

Patients on mechanical circulatory support are at high risk of bleeding, particularly intracranial hemorrhage (ICH). The management of ICH in patients needing anticoagulation and antiplatelet therapies remains a challenge. We report our initial experience of ICH management with low-molecular-weight heparin in patients with mechanical circulatory support, without bleeding or thromboembolic complications.     

Open elevated plus maze-induced antinociception in rats: A non-opioid type of pain inhibition?

CORNÉLIO, A. M. AND NUNES-DE-SOUZA, R. L. Open elevated plus maze-induced antinociception in rats: A non-opioid type of pain inhibition? PHYSIOL BEHAV 00 (0) 000-000, 2008. This study investigated whether antinociception induced by exposure to an open elevated plus-maze (oEPM: four open arms) (i) shows cross-tolerance to morphine (Exp. 1 and 2), (ii) is attenuated by repeated exposure to the oEPM (Exp. 3), (iii) is blocked by systemic treatment with naltrexone (Exp. 4), and (iv) is affected by adrenalectomy (Exp. 5) in rats. Animals were daily treated with morphine (M, 5 mg/kg, i.p.) or distilled water (DW) for 5 consecutive days (antinociceptive tolerance assessed by tail-flick test). Then, rats received formalin 2.5% injection (50 μl) into the right hind paw followed by M or DW injection and 25 min later, time spent licking the injected paw was recorded for 10 min (Exp. 1). Similar procedure was followed in Experiment 2, except that licking response was recorded during exposure to an oEPM or enclosed EPM (eEPM: four enclosed arms) in undrugged rats. Experiment 3 evaluated nociception in rats submitted to 1, 2, 3, 4 or 6 exposures to either eEPM or oEPM (formalin was injected only during the last exposure). Experiment 4 investigated the effects of naltrexone (2.5 mg/kg; s.c.) on nociception during eEPM or oEPM exposure. Nociception was also assessed during eEPM or oEPM exposure in sham and adrenalectomized rats (Exp. 5). The results shown that oEPM-induced antinociception (i) did not display cross-tolerance to morphine, (ii) was unchanged by at least 6 maze re-exposures, (iii) failed to be reversed by naltrexone, and (iv) was not prevented by adrenalectomy.     

Hypersociability in Williams syndrome: a role for the amygdala?

We read with great interest the paper of Riby et al. regarding atypical, unfamiliar face processing in Williams syndrome (WS; Riby, Doherty-Sneddon, & Bruce, 2008a). It offers considerable insight into the mechanism of facial perception in humans and a further elaboration of the hypersociability observed in patients with Williams syndrome. We would like to suggest that the neurologic mechanisms underlying the hypersociability in WS may be attributable to an impaired recognition of facial expressions of threat, a feature that localises to the amygdala.     

Outcomes associated with virtual reality in psychological interventions: where are we now?

The impending commercial release of affordable VR systems is likely to accelerate both the opportunity and demand for VR applications that specifically target psychological conditions. The aim of this study was to conduct a meta-analysis of outcomes associated with VR psychological interventions and to examine the methodological rigour used in these interventions. Literature search was conducted via Ovid, ProQuest Psychology Journals and ScienceDirect (Psychology) databases. Interventions were required to: be published between 1980 to 2014; use a randomised controlled trial design; be published in a scholarly journal; focused primarily on psychological/behavioural intervention; include validated measures; include reported means and standard deviations of outcome measures; and include one group with clinical/subclinical disorders, syndromes or distressing behaviours. Thirty eligible studies were identified. Random effects meta-analysis found an overall moderate effect size for VR interventions. Individual meta-analyses found an overall large effect size against non-intervention wait-lists and an overall moderate effect size against active interventions. No correlation was found between treatment outcomes and methodological rigour. Limitations may include limited study numbers, the use of a single coder, a need for more in-depth analyses of variation in form VR intervention, and omission of presence as a moderating factor. The current review supports VR interventions as efficacious, promising forms of psychological treatment. Use of reporting guidelines such as the CONSORT and CONSORT-EHEALTH statements should promote greater emphasis on methodological rigour, providing a firm foundation for the further development of clinical VR applications.