Comparative study of eosinophil chemotaxis, adhesion, and degranulation in vitro in ulcerative colitis and Crohn's disease

BACKGROUND: Eosinophils have been identified in tissues from patients with Crohn's disease (CD) and ulcerative colitis (UC) but whether they contribute to IBD pathogenesis is unknown. This study aimed to investigate the functional activity and morphological aspects of peripheral-blood eosinophils from IBD patients compared to those from healthy volunteers (HVs). METHODS: Eosinophils from HVs and CD and UC patients were purified using a Percoll gradient and then a immunomagnetic cell separator. Functional activity in inactivated and previously activated cells was investigated by measuring adhesion to fibronectin and chemotaxis to fMLP, and degranulation was measured by release of eosinophil peroxidase (EPO). Cell morphology was investigated using electron microscopy. RESULTS: Eosinophil adhesion to human fibronectin in both inactivated and PAF-stimulated and PMA-stimulated eosinophils was markedly higher in patients with CD than in either patients with UC or HVs. Similarly, the chemotactic response was markedly higher in eosinophils isolated from CD patients than in those isolated from UC patients or HVs. Baseline EPO release was higher in eosinophils isolated from UC patients than in those isolated from HVs or CD patients. Stimulation with fMLP or PMA did not further increase EPO release in cells from UC or CD patients. Comparable expression of MAC- 1 and VLA-4 adhesion molecules was observed on the surfaces of eosinophils from all groups, and an greater number of granules was noted in the eosinophils from UC patients than in those from CD patients. CONCLUSIONS: Our results indicate that peripheral-blood eosinophils are potentially primed and activated in IBD patients. Whether the differences in the morphology and functional responses of eosinophil from UC and CD patients reflect differences in disease phenotype remains to be elucidated.     

Memory impairment induced by an interfering task is reverted by pre-frontal cortex lesions: a possible role for an inhibitory process in memory suppression in mice

Interference theory refers to the idea that forgetting occurs because the recall of certain items interferes with the recall of other items. Recently, it has been proposed that interference is due to an inhibitory control mechanism, triggered by competing memories, that ultimately causes forgetting [Anderson MC (2003) Rethinking interference theory: Executive control and the mechanisms of forgetting. J Mem Lang 49:415-4453]. In the present research we study the interference process by submitting CD1 mice to two different hippocampal-dependent tasks: a place object recognition task (PORT) and a step-through inhibitory avoidance task (IA). Our results show a mutual interference between PORT and IA. To elucidate the possible neural mechanism underlying the interference process, we submit hippocampus- and prefrontal cortex-lesioned mice to PORT immediately before IA training. Results from these experiments show that prefrontal cortex lesions completely revert the impairing effect exerted by PORT administration on IA memory, while hippocampus lesions, that as expected impair memory for both PORT and IA, increase this effect. Altogether our results suggest that interference-induced forgetting is driven by an inhibitory control mechanism through activation of hippocampus-prefrontal cortex circuitry. The hippocampus seems to be crucial for storing information related to both behavioral tasks. Competition between memories triggers the inhibitory control mechanism, by activating prefrontal cortex, and induces memory suppression.     

Synthesis and biocompatibility of an experimental glass ionomer cement prepared by a non-hydrolytic sol-gel method

The aims of this study were to demonstrate the synthesis of an experimental glass ionomer cement (GIC) by the non-hydrolytic sol-gel method and to evaluate its biocompatibility in comparison to a conventional glass ionomer cement (Vidrion R). Four polyethylene tubes containing the tested cements were implanted in the dorsal region of 15 rats, as follows: GI - experimental GIC and GII - conventional GIC. The external tube walls was considered the control group (CG). The rats were sacrificed 7, 21 and 42 days after implant placement for histopathological analysis. A four-point (I-IV) scoring system was used to graduate the inflammatory reaction. Regarding the experimental GIC sintherization, thermogravimetric and x-ray diffraction analysis demonstrated vitreous material formation at 110oC by the sol-gel method. For biocompatibility test, results showed a moderate chronic inflammatory reaction for GI (III), severe for GII (IV) and mild for CG (II) at 7 days. After 21 days, GI presented a mild reaction (II); GII, moderate (III) and CG, mild (II). At 42 days, GI showed a mild/absent inflammatory reaction (II to I), similar to GII (II to I). CG presented absence of chronic inflammatory reaction (I). It was concluded that the experimental GIC presented mild/absent tissue reaction after 42 days, being biocompatible when tested in the connective tissue of rats.     

Effects of prostaglandin E(1) in the genesis of blood capillaries in the ischemic skeletal muscle of rats: ultrastructural analysis

Our aim was to study the ultrastructural aspects in the genesis of blood capillaries in the lower limb skeletal muscle of rats submitted to ischemia under the action of intramuscular or endovenous prostaglandin E(1) (PGE(1)). Twelve Wistar-UEM rats were used, randomly distributed into three groups of four animals each, equally redistributed into two subgroups, observed at 7 and 14 days as follows: group only with ischemia was considered as control (I), group with ischemia and intramuscular injection of PGE(1) (IM), and group with ischemia and endovenous injection of PGE(1) (EV). Results were analyzed by transmission electronic microscopy (TEM). TEM analysis revealed evidence of new capillary formation. TEM permitted us to identify morphological structures and phenomena in vascular neoformation that might have occurred through angiogenesis and/or vasculogenesis.     

Efficacy of Microneedling Versus Fractional Non-ablative Laser to Treat Striae Alba: A Randomized Study

American Journal of Clinical Dermatology - Striae distensae (SD), an unsightly cutaneous condition characterized by epidermal atrophy, can affect the quality of life of women. The aim of our study...     

Autoimmune hepatitis in 828 Brazilian children and adolescents: clinical and laboratory findings,histological profile,treatments, and outcomes

ObjectiveThis large study with a long-term follow-up aimed to evaluate the clinical presentation, laboratory findings, histological profile, treatments, and outcomes of children and adolescents with autoimmune hepatitis.MethodsThe medical records of 828 children and adolescents with autoimmune hepatitis were reviewed. A questionnaire was used to collect anonymous data on clinical presentation, biochemical and histological findings, and treatments.ResultsOf all patients, 89.6% had autoimmune hepatitis-1 and 10.4% had autoimmune hepatitis-2. The female sex was predominant in both groups. The median age at symptom onset was 111.5 (6; 210) and 53.5 (8; 165) months in the patients with autoimmune hepatitis 1 and autoimmune hepatitis-2, respectively. Acute clinical onset was observed in 56.1% and 58.8% and insidious symptoms in 43.9% and 41.2% of the patients with autoimmune hepatitis-1 and autoimmune hepatitis-2, respectively. The risk of hepatic failure was 1.6-fold higher for autoimmune hepatitis-2. Fulminant hepatic failure occurred in 3.6% and 10.6% of the patients with autoimmune hepatitis-1 and autoimmune hepatitis-2, respectively; the risk was 3.1-fold higher for autoimmune hepatitis-2. The gamma globulin and immunoglobulin G levels were significantly higher in autoimmune hepatitis-1, while the immunoglobulin A and C3 levels were lower in autoimmune hepatitis-2. Cirrhosis was observed in 22.4% of the patients; biochemical remission was achieved in 76.2%. The actuarial survival rate was 93.0%. A total of 4.6% underwent liver transplantation, and 6.9% died (autoimmune hepatitis-1: 7.5%; autoimmune hepatitis-2: 2.4%).ConclusionsIn this large clinical series of Brazilian children and adolescents, autoimmune hepatitis-1 was more frequent, and patients with autoimmune hepatitis-2 exhibited higher disease remission rates with earlier response to treatment. Patients with autoimmune hepatitis-1 had a higher risk of death.