Panicolytic-like effect induced by the stimulation of GABAA and GABAB receptors in the dorsal periaqueductal grey of rats

Activation of GABA(A) and benzodiazepine receptors within the dorsal periaqueductal grey inhibits the escape behaviour evoked by the electrical stimulation of this midbrain area, a defensive reaction that has been related to panic. Nevertheless, there is no evidence indicating whether the same antiaversive effect is also observed in escape responses evoked by species-specific threatening stimuli. In the present study, male Wistar rats were injected intra-dorsal periaqueductal grey with the benzodiazepine receptor agonist midazolam (10, 20 and 40 nmol), the GABA(A) receptor agonist muscimol (2, 4 and 8 nmol), the GABA(B) receptor agonist baclofen (2, 4 and 8 nmol), or with the benzodiazepine inverse agonist FG 7142 (20, 40 and 80 pmol) and tested in an ethologically-based animal model of anxiety, the elevated T-maze. Besides escape, this test also allows the measurement of inhibitory avoidance which has been related to generalised anxiety disorder. Midazolam, muscimol and baclofen impaired escape, a panicolytic-like effect, without altering inhibitory avoidance. FG 7142, on the other hand, facilitated both avoidance and escape reactions, suggesting an anxiogenic and panicogenic-like effect, respectively. The data suggest that GABA(A)/benzodiazepine and GABA(B) receptors within the dorsal periaqueductal grey are involved in the control of escape behaviour and that a failure in this regulatory mechanism may be of importance in panic disorder.     

Assessment of three rapid methods for the detection of methicillin-resistant Staphylococcus aureus

We evaluated three rapid methods to detect methicillin-resistant Staphylococcus aureus (MRSA) and compared them with PCR amplification of mecA. A total of 103 S. aureus strains were studied by MRSA-Screen, BBL Crystal, Velogene Genomic and mecA PCR. All the methods detected the 61 MRSA strains having the mecA gene, showing 100% sensitivity and specificity. Despite the correlation between all the rapid methods and PCR, the ease of use and shorter turnaround time of MRSA-Screen were important factors leading to the selection of this method as the routine screening technique for MRSA.     

Kawasaki disease and sensorineural hearing loss: an (un)expected complication

Kawasaki disease (KD) is an acute, self-limiting, idiopathic form of vasculitis. The preventive effect of early therapy on coronary artery aneurysms, the hallmark of the disease, is well established. The spectrum of complication includes not only cardiac involvement but also central nervous system lesions. We report a 4-year-old boy with a clinical presentation suggestive of KD treated with intravenous immunoglobulin and acetylsalicylic acid. Clinical manifestations regressed within 24 hours and cardiac anomalies were not seen. Two weeks later, the parents noticed a sudden absence of response to sound stimuli. Investigations confirmed bilateral severe sensorineural hearing loss for which oral steroid therapy was given. This resulted in an improvement only on the right side, with severe hearing loss persisting on the left. Conclusion: Sensorineural hearing loss is an uncommonly reported complication of KD. Pediatricians should be aware of this potential complication to allow for early intervention.     

A novel type of familial proximal axonal dystrophy: three cases and a review of the axonal dystrophies

Three related infants of Roma ancestry, two of them siblings, showed hypotonia, predominantly axial, from birth, difficulty swallowing, myoclonic seizures, and respiratory difficulty. Dysmorphic features, principally micrognathia were present. EEGs showed focal epileptiform abnormalities. All three died in their 5th month from respiratory insufficiency complicated by pneumonia. Autopsy showed small brains without malformation. Microscopy revealed numerous axonal spheroids involving particularly the brain stem and spinal cord, with especial prominence in the middle cerebellar peduncle, the anterior part of the thalamic reticular nuclei, and the anterior horns and columns of the spinal cord. Spheroids that appeared to be on axons of lower motor neurons were especially large. No spheroids were seen in peripheral nerves; electron microscopy did not show spheroids in skin. By electron microscopy spheroids contained neurofilaments, sparse mitochondria, and electron dense granules. The material did not allow identification of microtubules. Closely packed vesicles excluded neurofilamanets from the center of many spheroids, especially in the middle cerebellar peduncle. Sprouting of axons from the surface of many spheroids was seen. This disease is distinct from the well described type of infantile neuroaxonal dystrophy (Seitelberger's disease) in view of the distribution of spheroids, presence of spheroids on proximal rather than distal parts of axons, sparing of the peripheral nerves, lack of staining for synuclein, presence of sprouting, and lack of membranous profiles in the spheroids. A review of reported types of axonal dystrophy has not shown identical cases.     

Metastatic Adenocarcinoma of the Colon: Early Manifestation in Gingival Tissue

A case of gingival metastasis of adenocarcinoma of the colon is reported, the lesion being an early clinical indication of a primary malignant tumor. The diagnosis of metastatic lesion in the oral region is always challenging, both to clinician and to the pathologist, due to its rarity and complexity. In the present case, the clinical hypothesis was peripheral ossifying fibroma or pyogenic granuloma. Histologically, the biopsy tissue revealed a malignant neoplasm not connected to the mucosal surface. Immunohistochemically, the lesion was positive for 35ßH11 and cytokeratin 20 and focally positive for cytokeratin 7. Treatment involved excision of primary tumor and follow-up chemotherapy. The clinical, histological and immunohistochemical characteristics are discussed.     

Effect of exercise on cognitive performance in community-dwelling older adults: review of intervention trials and recommendations for public health practice and research

There is evidence from observational studies that increasing physical activity may reduce the risk of cognitive decline in older adults. Exercise intervention trials have found conflicting results. A systematic review of physical activity and exercise intervention trials on cognition in older adults was conducted. Six scientific databases and reference lists of previous reviews were searched. Thirty studies were eligible for inclusion. Articles were grouped into intervention-outcome pairings. Interventions were grouped as cardiorespiratory, strength, and multicomponent exercises. Cognitive outcomes were general cognition, executive function, memory, reaction time, attention, cognitive processing, visuospatial, and language. An eight-member multidisciplinary panel rated the quality and effectiveness of each pairing. Although there were some positive studies, the panel did not find sufficient evidence that physical activity or exercise improved cognition in older adults. Future research should report exercise adherence, use longer study durations, and determine the clinical relevance of measures used.