163 resultados para PERSISTENT LUMINESCENCE
Resumo:
Allergic rhinitis (AR) typically presents after the second year of life, but the exact prevalence in early life is unknown. AR affects 10-30% of the population, with the greatest frequency found in children and adolescents. It appears that the prevalence has increased in the pediatric population. As the childs` immune system develops between the 1st and 4th yr of life, those with an atopic predisposition begin to express allergic disease with a clear Th(2) response to allergen exposure, resulting in symptoms. In pediatric AR, two or more seasons of pollen exposure are generally needed for sensitization, so allergy testing to seasonal allergens (trees, grasses, and weeds) should be conducted after the age of 2 or 3 years. Sensitization to perennial allergens (animals, dust mites, and cockroaches) may manifest several months after exposure. Classification of AR includes measurement of frequency and duration of symptoms. Intermittent AR is defined as symptoms for < 4 days/wk or < 4 consecutive weeks. Persistent AR is defined as occurring for more than 4 days/wk and more than 4 consecutive weeks. AR is associated with impairments in quality of life, sleep disorders, emotional problems, and impairment in activities such as work and school productivity and social functioning. AR can also be graded in severity - either mild or moderate/severe. There are comorbidities associated with AR. The chronic effects of the inflammatory process affect lungs, ears, growth, and others. AR can induce medical complications, learning problems and sleep-related complaints, such as obstructive sleep apnea syndrome and chronic and acute sinusitis, acute otitis media, serous otitis media, and aggravation of adenoidal hypertrophy and asthma.
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The peptides Tx2-5 and Tx2-6, isolated from the whole venom of ""armed-spider"" Phoneutria nigniventer venom, are directly linked with the induction of persistent and painful erection in the penis of mammals. The erection induced by Tx2-6 has been associated with the activation of nitric oxide synthases. There is a scarcity of studies focusing on the outcome of Tx2-6 at the molecular level, by this reason we evaluated the gene profile activity of this toxin at the nitric oxide (NO) pathway. After microarray analyses on cavernous tissue of mice inoculated with Tx2-6 we found that only 10.4% (10/96) of these genes were differentially expressed, showing a limited effect of the toxin on the NO pathway. We found the genes sparc, ednrb, junb, cdkn1a, bcl2, ccl5, abcc1 over-expressed and the genes sod1, s100a10 and fth1 under-expressed after inoculation of Tx2-6. The differential expressions of sparc and ednrb genes were further confirmed using real-time PCR. Interestingly, ednrb activates the L-arginine/NO/cGMP pathway that is involved in the relaxation of the cavernous body. Therefore the priapism induced by Tx2-6 is a consequence of a highly specific interference of this neurotoxin with the NO pathway. (C) 2009 Elsevier Ltd. All rights reserved.
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Background and Purpose-Diagnostic delay of cerebral vein and dural sinus thrombosis may have an impact on outcome. Methods-In the International Study on Cerebral Vein and Dural Sinus Thrombosis (ISCVT) cohort (624 patients with cerebral vein and dural sinus thrombosis), we analyzed the predictors and the impact on outcome of diagnostic delay. Primary outcome was a modified Rankin Scale score > 2 at the end of follow-up. Secondary outcomes were modified Rankin Scale score 0 to 1 at the end of follow-up, death, and visual deficits (visual acuity or visual field). Results-Median delay was 7 days (interquartile range, 3 to 16). Patients with disturbance of consciousness (P < 0.001) and of mental status (P = 0.042), seizure (< 0.001), and with parenchymal lesions on admission CT/MR (P < 0.001) were diagnosed earlier, whereas men (P = 0.01) and those with isolated intracranial hypertension syndrome (P = 0.04) were diagnosed later. Between patients diagnosed earlier and later than the median delay, no statistically significant differences were found in the primary (P = 0.33) and in secondary outcomes: modified Rankin Scale score 0 to 1 (P = 0.86) or deaths (P = 0.53). Persistent visual deficits were more frequent in patients diagnosed later (P = 0.05). In patients with isolated intracranial hypertension syndrome, modified Rankin Scale score > 2 at the end of follow-up was more frequent in patients diagnosed later (P = 0.02). Conclusions-Diagnostic delay was considerable in this cohort and was associated with an increased risk of visual deficit. In patients with isolated intracranial hypertension syndrome, diagnostic delay was also associated with death or dependency. (Stroke. 2009; 40: 3133-3138.)
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Juvenile systemic lupus erythematosus (JSLE) and autoimmune hepatitis (AIH) are both autoimmune disorders that are rare in children and have a widespread clinical manifestation. A few case reports have shown a JSLE-AIH associated disorder. To our knowledge, this is the first study that simultaneously evaluated the prevalence of JSLE-AIH in a large JLSE and AIH population in groups of Hepatology and Rheumatology of a tertiary Paediatric University Hospital. In a 24-year period, 228 patients were diagnosed with JSLE (ACR criteria). In the same period, 252 patients were diagnosed with AIH according to the International Autoimmune Hepatitis Group. In this article, we present the demographic data, clinical features, laboratory exams and treatment of four children with both the diseases. The prevalence was 1.8% in JSLE population and was 1.6% in AIH population. The current median age was 15.5 years and three were females. In three of them, the diagnosis of AIH preceded JSLE. All of them had increased liver enzymes with a characteristic liver biopsy of AIH and responded to the combination of prednisone, azathioprine and antimalarial drugs. In conclusion, the presence of AIH-JSLE associated disorder was rarely observed. The liver biopsy could be necessary in patients with JLSE with a persistent increase of liver enzymes. Lupus (2009) 18, 747-751.
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Over the last few decades, inhaled corticosteroids (ICs) became the cornerstone in the treatment of persistent asthma. Their use improved asthma control, decreased mortality and also minimized adverse reactions associated with systemic steroid. Esophageal candidiasis is a rare complication resulting from the use of ICs. Although, in recent years, as their prescriptions has increased, more cases have been reported, especially in Japan. Listed are 4 case reports regarding esophageal candidiasis in asthmatic patients associated with inhaled budesonide administration. In the cases reported herein, the use of a different device of dry powder budesonide might have favored esophageal drug deposition and Candida infection. Patients denied using systemic corticosteroids in the previous 6 months. Furthermore, none of the patients presented Diabetes mellitus, malignant disease, HIV infection, or other immunosuppressive conditions. We conclude that patients treated with high doses of ICs are at higher risk of developing esophageal candidiasis. These patients should undergo upper gastrointestinal endoscopy whenever they present symptoms. Nevertheless, we must keep in mind that infection might also be asymptomatic and esophageal candidiasis prevalence may be higher than that reported thus far.
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The pathogenic mechanisms of Leptospira interrogans, the causal agent of leptospirosis, remain largely unknown. This is mainly due to the lack of tools for genetically manipulating pathogenic Leptospira species. Thus, homologous recombination between introduced DNA and the corresponding chromosomal locus has never been demonstrated for this pathogen. Leptospiral immunoglobulin-like repeat (Lig) proteins were previously identified as putative Leptospira virulence factors. In this study, a ligB mutant was constructed by allelic exchange in L. interrogans; in this mutant a spectinomycin resistance (Spc(r)) gene replaced a portion of the ligB coding sequence. Gene disruption was confirmed by PCR, immunoblot analysis, and immunofluorescence studies. The ligB mutant did not show decrease virulence compared to the wild-type strain in the hamster model of leptospirosis. In addition, inoculation of rats with the ligB mutant induced persistent colonization of the kidneys. Finally, LigB was not required to mediate bacterial adherence to cultured cells. Taken together, our data provide the first evidence of site-directed homologous recombination in pathogenic Leptospira species. Furthermore, our data suggest that LigB does not play a major role in dissemination of the pathogen in the host and in the development of acute disease manifestations or persistent renal colonization.
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We have investigated the effect of pcDNA3-CpG and pcDNA-IL-12, delivered by intradermal gene gun administration, on the blood/lung eosinophilia, airway hyperresponsiveness as well as the immune response in a murine model of toxocariasis. Our results demonstrated that pcDNA-IL-12 but not pcDNA3-CpG vaccination Led to a persistent tower blood/bronchoalveolar eosinophilia following Toxocaro conis infection, as pcDNA3-CpG led only to an early transient blockage of eosinophil transmigration into bronchoalveolar fluid following T canis infection. Prominent Type-1 immune response was pointed out as the halt-mark of T canis infection following pcDNA-IL-12 vaccination. Outstanding IFN-gamma/IL-4 ratio besides tow levels of IgG1 with subsequent high IgG2a/IgG1 ratio further characterized a Type-1 polarized immunological profile in pcDNA-IL-12-vaccinated animals. Nevertheless, only pcDNA3-CpG was able to prevent airway hyperresponsiveness induced by T canis infection. The persistent airway hyperresponsiveness observed in pcDNA-IL-12-vaccinated animals demonstrated that the airway constriction involved other immunological mediator than those blocked by pcDNA-IL-12. Together, these data indicated that pcDNA-IL-12 and pcDNA3-CpG vaccines have distinct therapeutic benefits regarding the eosinophilic inflammation/airway hyperresponsiveness triggered by T canis infection, suggesting their possible use in further combined therapeutic interventions. (c) 2007 Elsevier Ltd. All rights reserved.
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P>Strongyloides stercoralis is an intestinal nematode capable of chronic, persistent infection and hyperinfection of the host; this can lead to dissemination, mainly in immunosuppressive states, in which the infection can become severe and result in the death of the host. In this study, we investigated the immune response against Strongyloides venezuelensis infection in major histocompatibility complex (MHC) class I or class II deficient mice. We found that MHC II(-/-) animals were more susceptible to S. venezuelensis infection as a result of the presence of an elevated number of eggs in the faeces and a delay in the elimination of adult worms compared with wild-type (WT) and MHC I(-/-) mice. Histopathological analysis revealed that MHC II(-/-) mice had a mild inflammatory infiltration in the small intestine with a reduction in tissue eosinophilia. These mice also presented a significantly lower frequency of eosinophils and mononuclear cells in the blood, together with reduced T helper type 2 (Th2) cytokines in small intestine homogenates and sera compared with WT and MHC I(-/-) animals. Additionally, levels of parasite-specific immunoglobulin M (IgM), IgA, IgE, total IgG and IgG1 were also significantly reduced in the sera of MHC II(-/-) infected mice, while a non-significant increase in the level of IgG2a was found in comparison to WT or MHC I(-/-) infected mice. Together, these data demonstrate that expression of MHC class II but not class I molecules is required to induce a predominantly Th2 response and to achieve efficient control of S. venezuelensis infection in mice.
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Background and Aims: Endoscopic ultrasound (EUS) is useful for the treatment of sterile pancreatic fluid collections (PFC), either by means of transmural drainage or by complete aspiration. The aim of this study was to evaluate the efficacy and safety of single-step EUS-guided endoscopic approaches for treatment of sterile PFC. Patients and Methods: During a 3-year period, 77 consecutive patients with symptomatic, persistent sterile PFC were evaluated and treated with the linear EUS. We excluded patients with grossly purulent collections, chronic pseudocyst and those whose cytology diagnostic was neoplastic cyst of pancreas. 44 patients received a single 10-Fr plastic straight stent under EUS or fluoroscopic control (group I) and 33 of these underwent a single-step complete aspiration with a 19-gauge needle (group II). Results: The mean size of the sterile PFC was 48 mm in group I and 28 mm in group II (p < 0.001). Overall, endoscopic treatment was successful in 70 (90.9%) patients. The mean volume aspirated was 25 (18-65) ml. The total number of procedures was 50 in group I and 41 punctures in group II. After a mean follow-up of 64 +/- 15.6 weeks there were 6 complications 13.6%): 2 recurrences (referred to surgery), 2 developing abscesses (submitted a new EUS-guided endoscopic drainage with success), 1 perforation that died (2.2%), and 1 case of bleeding (sent to surgery) in group I. In group II there were only 6 (18.1%) recurrences (submitted a new EUS-guided aspiration). None of the patients undergoing single-step aspiration developed infections, perforation or hemorrhage. Conclusion: The recurrence of pancreatic pseudocysts after endoscopic treatment was similar, either by means of plastic stents or by complete single-step aspiration. Copyright (C) 2009 S. Karger AG, Basel
Resumo:
Folic acid (FA) supplementation during carcinogenesis is controversial. Considering the impact of liver cancer as a public health problem and mandatory FA fortification in several countries, the role of FA supplementation in hepatocarcinogenesis should be elucidated. We evaluated FA supplementation during early hepatocarcinogenesis. Rats received daily 0.08 mg (FA8 group) or 0.16 mg (FA16 group) of FA/100 g body weight or water (CO group, controls). After a 2-week treatment, animals were subjected to the ""resistant hepatocyte"" model of hepatocarcinogenesis (initiation with diethylnitrosamine, selection/promotion with 2-acetylaminofluorene and partial hepatectomy) and euthanized after 8 weeks of treatment. Compared to the CO group, the FA16 group presented: reduced (p < 0.05) number of persistent and increased (p < 0.05) number of remodeling glutathione S-transferase (GST-P) positive preneoplastic lesions (PNL); reduced (p < 0.05) cell proliferation in persistent GST-P positive PNL; decreased (p < 0.05) hepatic DNA damage; and a tendency (p < 0.10) for decreased c-myc expression in microdissected PNL. Regarding all these parameters, no differences (p > 0.05) were observed between CO and FA8 groups. FA-treated groups presented increased hepatic levels of S-adenosylmethionine but only FA16 group presented increased S-adenosylmethionine/S-adenosylhomocysteine ratio. No differences (p > 0.05) were observed between experimental groups regarding apoptosis in persistent and remodeling GST-P positive PNL, and global DNA methylation pattern in microdissected PNL. Altogether, the FA16 group, but not the FA8 group, presented chemopreventive activity. Reversion of PNL phenotype and inhibition of DNA damage and of c-myc expression represent relevant FA cellular and molecular effects.
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Background: Most cases of congenital clubfoot treated with the Ponseti technique require percutaneous Achilles tenotomy to correct the residual equinus. Clinical evidence suggests that complete healing occurs between the cut tendon stumps, but there have not yet been any detailed studies investigating this reparative process. This study was performed to assess Achilles tendon repair after percutaneous section to correct the residual equinus of clubfoot treated with the Ponseti method. Method: A prospective study analyzed 37 tenotomies in 26 patients with congenital clubfoot treated with the Ponseti technique, with a minimum follow-up of 1 year after the section. The tenotomy was performed percutaneously with a large-bore needle bevel with patient sedation and local anesthesia. Ultrasonographic scanning was performed after section to ascertain that the tenotomy had been completed and to measure the stump separation. In the follow-up period, the reparative process was followed ultrasonographically and assessed at 3 weeks, 6 months, and 1 year posttenotomy. Results: The ultrasonography performed immediately after the procedure showed that in some cases, residual strands between the tendon ends persisted, and these were completely sectioned under ultrasound control. A mean retraction of 5.65 mm +/- 2.26 mm (range, 2.3 to 11.0 mm) between tendon stumps after section was observed. Unusual bleeding occurred in one case and was controlled by digital pressure, with no interference with the final treatment. After 3 weeks, ultrasonography showed tendon repair with the tendon gap filled with irregular hypoechoic tissue, and also with transmission of muscle motion to the heel. Six months after tenotomy, there was structural filling with a fibrillar aspect, mild or moderate hypoechogenicity, and tendon scar thickening when compared with a normal tendon. One year after tenotomy, ultrasound showed a fibrillar structure and echogenicity at the repair site that was similar to a normal tendon, but with persistent tendon scarring thickness. Conclusions: There is a fast reparative process after Achilles tendon percutaneous section that reestablishes continuity between stumps. The reparative tissue evolved to tendon tissue with a normal ultrasonographic appearance except for mild thickening, suggesting a predominantly intrinsic repair mechanism.
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Objectives: To determine if systemic stress affects the biological reactions occurring during orthodontic tooth movement. Methods: Four groups of male 10 week-old Wistar rats were used. Group A animals (N=10) were restrained for one hour per day for 40 days; Group B animals (N=10) were restrained for one hour per day for three days; Group C (N=10) and Group D (N=8) animals were unrestrained. The upper left first molars in the rats in Groups A (long-term stress), B (short-term stress) and C (control) were moved mesially during the last 14 days of the experiment. The animals in Group D (N=8) were used for body weight and hormonal dosage comparisons only. They were not subjected to any stress and did not have appliances fitted. All animals were killed at 18 weeks of age and blood collected for measurement of plasma corticosterone. Tooth movement was measured with an electronic caliper. The right and left hemi-maxillae of five rats from each group were removed and the number of tartrate-resistant acid phosphatase (TRAP) positive cells, defined as osteoclasts, adjacent to the mesial roots of the upper first molars counted. The contralateral side in each animal served as the control (split-mouth design). Results: Corticosterone levels were significantly higher in the stressed groups (Groups A and B) than in the control group (Group C). Tooth movement was significantly greater in Group A (long-term stress) compared with Group B (short-term stress) and Group C (control), which did not differ from each other. There were significantly more osteoclasts in the long-term stress group than in the short-term stress and control groups. Conclusion: Persistent systemic stress increases bone resorption during orthodontic tooth movement. Systemic stress may affect the rate of tooth movement during orthodontic treatment.
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Sepsis is still a major cause of mortality in the intensive critical care unit and results from an overwhelming immune response to the infection. TNF signaling pathway plays a central role in the activation of innate immunity in response to pathogens. Using a model of polymicrobial sepsis by i.p. injection of cecal microflora, we demonstrate a critical role of TNFR1 and R2 activation in the deregulated immune responses and death associated with sepsis. A large and persistent production of TNF was found in wild-type (B6) mice. TNFR1/R2-deficient mice, compared with B6 mice, survive lethal polymicrobial infection with enhanced neutrophil recruitment and bacterial clearance in the peritoneal cavity. Absence of TNFR signaling leads to a decreased local and systemic inflammatory response with diminished organ injury. Furthermore, using TNFR1/R2-deficient mice, TNF was found to be responsible for a decrease in CXCR2 expression, explaining reduced neutrophil extravasation and migration to the infectious site, and in neutrophil apoptosis. In line with the clinical experience, administration of Enbrel, a TNF-neutralizing protein, induced however only a partial protection in B6 mice, with no improvement of clinical settings, suggesting that future TNF immunomodulatory strategies should target TNFR1 and R2. In conclusion, the present data suggest that the endogenous TNFR1/R2 signaling pathway in polymicrobial sepsis reduces neutrophil recruitment contributing to mortality and as opposed to pan-TNF blockade is an important therapeutic target for the treatment of polymicrobial sepsis. The Journal of Immunology, 2009, 182: 7855-7864.
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In the present study, the participation of the Na(v)1.8 sodium channel was investigated in the development of the peripheral pro-nociceptive state induced by daily intraplantar injections of PGE(2) in rats and its regulation in vivo by protein kinase A (PKA) and protein kinase C epsilon (PKC epsilon) as well. In the prostaglandin E(2) (PGE(2))-induced persistent hypernociception, the Na(v)1.8 mRNA in the dorsal root ganglia (DRG) was up-regulated. The local treatment with dipyrone abolished this persistent hypernociception but did not alter the Na(v)1.8 mRNA level in the DRG. Daily intrathecal administrations of antisense Na(v)1.8 decreased the Na(v)1.8 mRNA in the DRG and reduced ongoing persistent hypernociception. once the persistent hypernociception had been abolished by dipyrone, but not by Na(v)1.8 antisense treatment, a small dose of PGE(2) restored the hypernociceptive plateau. These data show that, after a period of recurring inflammatory stimuli, an intense and prolonged nociceptive response is elicited by a minimum inflammatory stimulus and that this pro-nociceptive state depends on Na(v)1.8 mRNA up-regulation in the DRG. in addition, during the persistent hypernociceptive state, the PKA and PKC epsilon expression and activity in the DRG are up-regulated and the administration of the PKA and PKC epsilon inhibitors reduce the hypernociception as well as the Na(v)1.8 mRNA level. In the present study, we demonstrated that the functional regulation of the Na(v)1.8 mRNA by PKA and PKC epsilon in the primary sensory neuron is important for the development of the peripheral pro-nociceptive state induced by repetitive inflammatory stimuli and for the maintenance of the behavioral persistent hypernociception. (C) 2008 Elsevier Inc. All rights reserved.
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Background and purpose: Protein kinase (PK) A and the epsilon isoform of PKC (PKC epsilon) are involved in the development of hypernociception (increased sensitivity to noxious or innocuous stimuli) in several animal models of acute and persistent inflammatory pain. The present study evaluated the contribution of PKA and PKC epsilon to the development of prostaglandin E(2) (PGE(2))-induced mechanical hypernociception. Experimental approach: Prostaglandin E(2)-induced mechanical hypernociception was assessed by constant pressure rat paw test. The activation of PKA or PKC epsilon was evaluated by radioactive enzymic assay in the dorsal root ganglia (DRG) of sensory neurons from the hind paws. Key results: Hypernociception induced by PGE(2) (100 ng) by intraplantar (i.pl.) injection, was reduced by i.pl. treatment with inhibitors of PKA [A-kinase-anchoring protein St-Ht31 inhibitor peptide (AKAPI)], PKC epsilon (PKC epsilon I) or adenylyl cyclase. PKA activity was essential in the early phase of the induction of hypernociception, whereas PKC activity was involved in the maintenance of the later phase of hypernociception. In the DRG (L4-L5), activity of PKA increased at 30 min after injection of PGE(2) but PKC activity increased only after 180 min. Moreover, i.pl. injection of the catalytic subunit of PKA induced hypernociception which was markedly reduced by pretreatment with an inhibitor of PKC epsilon, while the hypernociception induced by paw injection of PKC epsilon agonist was not affected by an inhibitor of PKA (AKAPI). Conclusions and implications: Taken together, these findings are consistent with the suggestion that PKA activates PKC epsilon, which is a novel mechanism of interaction between these kinases during the development of PGE(2)-induced mechanical hypernociception.