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AIMS: To evaluate the inhibitory effect of five structurally different imidazolium salts on the in vitro growth of plant pathogenic bacteria that belong to divergent taxonomic genera as well as their ability to reduce the severity of common bacterial blight of common bean caused by Xanthomonas axonopodis pv. phaseoli and bacterial speck of tomato caused by Pseudomonas syringae pv. tomato. METHODS AND RESULTS: Growth inhibition of Xanthomonas, Pseudomonas, Erwinia, Pectobacterium and Dickeya strains by imidazolium salts was assessed in vitro by radial diffusion on agar medium and by ressazurin reduction in liquid medium. The reduction of common bacterial blight and bacterial speck symptoms and the area under de disease progress curves were determined by spraying two selected imidazolium salts on healthy plants 48 h prior to inoculation with virulent strains of the bacterial pathogens. All imidazolium salts inhibited the growth of all plant pathogenic bacteria when tested by radial diffusion on agar medium. The strength of inhibition differed among imidazolium salts when tested on the same bacterial strain and among bacterial strains when tested with the same imidazolium salt. In liquid medium, most imidazolium salts presented the same minimum inhibitory concentration (MIC) and minimum bactericidal concentration values (200 µmol l-1 ), the most notable exception of which was the MIC (at least 1000 µmol l-1 ) for the dicationic MImC10 MImBr2 . The imidazolium salts C16 MImBr and C16 MImCl caused significant reductions in the severity of common bacterial blight symptoms when compared with nontreated plants. CONCLUSION: Imidazolium salts inhibit the in vitro growth of plant pathogenic bacteria and reduce plant disease symptoms to levels comparable to an authorized commercial antibiotic product. SIGNIFICANCE AND IMPACT OF THE STUDY: New compounds exhibiting broad-spectrum antibacterial activity with potential use in agriculture were identified.

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Human leukocyte antigen (HLA)–E is a non-classical molecule of the histocompatibility complex that functions as one of the main ligands of the Natural Killer (NK) cell inhibitory receptor CD94/NKG2A and inhibits its potent cytotoxic activity. Due to the important role of NK cells in combating neoplasm, we hypothesized that the differential expression of HLA-E could favor the progression of heterogeneous thyroid tumors.Using an immunohistochemistry technique in 143 biopsies of thyroid tumors, including benign and malignant neoplasms and goiters, we evaluated the expression of HLA-E among various tumor types and its association with the clinicopathological factors of diseases. We verified high HLA-E expression in all types of neoplastic tumors, although no significant differences between the groups were found. Low expression was observed in 95 percent of the goiter samples, showing significant differences between neoplastic and non-neoplastic lesions. Furthermore, a significant result was found with regard to the tumor size, with high HLA-E expression being related to smaller tumors. Therefore, our data suggest that an increase in HLA-E may be associated with the establishment of thyroid neoplasms, with either benign or malignant features.

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BACKGROUND: The nonclassical human leucocyte antigen (HLA)-G molecule has been well recognized as a tolerogenic molecule and few studies have evaluated the role of the molecule in inflammatory cutaneous autoimmune diseases. OBJECTIVES: To evaluate the expression of HLA-G in skin specimens of patients with psoriasis and to analyse its correlation with epidemiological and clinical variables. METHODS: Thirty untreated patients with psoriasis and 32 healthy individuals were enrolled. Immunohistochemistry was applied to identify HLA-G expression in formalin-fixed paraffin-embedded cutaneous skin biopsies. RESULTS: Soluble and membrane-bound HLA-G expression was detected in 30 (90%) of the skin specimens from patients presenting clinical and histopathological features of psoriasis. Although infiltrating lymphomononuclear cells of the dermis exhibited HLA-G expression, the epidermis was primarily targeted. HLA-G expression was also observed in 27% (three of 11) of the specimens that exhibited no clinical and histopathological features of psoriasis (nonaffected areas). In contrast, skin specimens obtained from healthy individuals exhibited no HLA-G expression (P < 0·0001). The intensity of HLA-G expression was not associated with type I/II psoriasis, Psoriasis Area and Severity Index score or clinical forms. CONCLUSIONS: As the HLA-G molecule was consistently expressed in affected and, to a lesser extent, in nonaffected areas of untreated patients with psoriasis, irrespective of the severity of the clinical variants, one may hypothesize that the presence of HLA-G may be responsible, at least in part, for the regulation of autoimmune effector cells.

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The use of ethyl-cyanoacrylate and octyl-cyanoacrylate were clinically and histopathologically compared on the corneas of 36 rabbits after lamellar keratectomy (standardized diameter and depth). The animals were distributed into two groups, one for each type of adhesive. From each group, six subgroups were histopathologically evaluated on the 3rd, 7th, 14th, 21st, 30th, and 60th day post-operative. General (daily) and ophthalmic (days 0, 1, 3, 5, 7, 14, 21, 30, 44, and 60) evaluations clinically indicated that there were significant differences for the variables water intake, attitude, blepharitis, corneal edema, and fluorescein test. The adhesive permanence time for octyl-cyanoacrylate (17.22 days) was greater than that for ethyl-cyanoacrylate (7.66 days). With respect to the histopathological evaluation, corneal epithelization and collagen organization occurred without severe complications. However, treatment with ethyl-cyanoacrylate led to a moderate inflammatory reaction in the initial phases. With octyl-cyanoacrylate, re-epithelization and collagen organization proceeded more slowly with a discrete inflammatory reaction in the initial phases. From clinical and histopathologic points of view, octyl-cyanoacrylate showed advantages over ethyl-cyanoacrylate, whereas wound healing was achieved in both groups without major complications.(AU)

Comparou-se o uso do etil-cianoacrilato e do octil-cianoacrilato em córneas de 36 coelhos após ceratectomia lamelar (diâmetro e profundidade padronizados). Os animais foram distribuídos em dois grupos, segundo o tipo de adesivo, e redistribuídos em seis subgrupos com três animais cada, para as avaliações histológicas aos 3, 7, 14, 21, 30 e 60 dias de pós-operatório. As avaliações clínicas gerais (diárias) e as oftálmicas (dias 0, 1, 3, 5, 7, 14, 21, 30, 44 e 60), indicaram diferença entre os dois grupos, quanto ao consumo de água, atitude, blefarite, edema da córnea e teste da fluoresceína. O Tempo de permanência, sobre o leito corneal, do adesivo octil-cianoacrilato (17,22 dias), foi maior que o do etil-cianoacrulato (7,66 dias). A histopatologia, para ambos os grupos, mostrou que a re-epitelização e a organização do colágeno ocorreram sem graves intercorrências. O grupo tratado com o etil-cianoacrilato apresentou, nas fases iniciais, reação inflamatória mais evidente que o tratado com octil-cianoacrilato. Neste, a re-epitelização e a organização do colágeno ocorreram mais lentamente e com reação inflamatória discreta. Sob os pontos de vista clínico e de avaliação histológica simples, os resultados mostraram vantagens do octil-cianoacrilato, entretanto, a cicatrização da córnea ocorreu em ambos os grupos.(AU)

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The use of ethyl-cyanoacrylate and octyl-cyanoacrylate were clinically and histopathologically compared on the corneas of 36 rabbits after lamellar keratectomy (standardized diameter and depth). The animals were distributed into two groups, one for each type of adhesive. From each group, six subgroups were histopathologically evaluated on the 3rd, 7th, 14th, 21st, 30th, and 60th day post-operative. General (daily) and ophthalmic (days 0, 1, 3, 5, 7, 14, 21, 30, 44, and 60) evaluations clinically indicated that there were significant differences for the variables water intake, attitude, blepharitis, corneal edema, and fluorescein test. The adhesive permanence time for octyl-cyanoacrylate (17.22 days) was greater than that for ethyl-cyanoacrylate (7.66 days). With respect to the histopathological evaluation, corneal epithelization and collagen organization occurred without severe complications. However, treatment with ethyl-cyanoacrylate led to a moderate inflammatory reaction in the initial phases. With octyl-cyanoacrylate, re-epithelization and collagen organization proceeded more slowly with a discrete inflammatory reaction in the initial phases. From clinical and histopathologic points of view, octyl-cyanoacrylate showed advantages over ethyl-cyanoacrylate, whereas wound healing was achieved in both groups without major complications.

Comparou-se o uso do etil-cianoacrilato e do octil-cianoacrilato em córneas de 36 coelhos após ceratectomia lamelar (diâmetro e profundidade padronizados). Os animais foram distribuídos em dois grupos, segundo o tipo de adesivo, e redistribuídos em seis subgrupos com três animais cada, para as avaliações histológicas aos 3, 7, 14, 21, 30 e 60 dias de pós-operatório. As avaliações clínicas gerais (diárias) e as oftálmicas (dias 0, 1, 3, 5, 7, 14, 21, 30, 44 e 60), indicaram diferença entre os dois grupos, quanto ao consumo de água, atitude, blefarite, edema da córnea e teste da fluoresceína. O Tempo de permanência, sobre o leito corneal, do adesivo octil-cianoacrilato (17,22 dias), foi maior que o do etil-cianoacrulato (7,66 dias). A histopatologia, para ambos os grupos, mostrou que a re-epitelização e a organização do colágeno ocorreram sem graves intercorrências. O grupo tratado com o etil-cianoacrilato apresentou, nas fases iniciais, reação inflamatória mais evidente que o tratado com octil-cianoacrilato. Neste, a re-epitelização e a organização do colágeno ocorreram mais lentamente e com reação inflamatória discreta. Sob os pontos de vista clínico e de avaliação histológica simples, os resultados mostraram vantagens do octil-cianoacrilato, entretanto, a cicatrização da córnea ocorreu em ambos os grupos.

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We previously reported the anti-inflammatory activity of Lafoensia pacari extract in Toxocara canis infection, a model of systemic IL-5-dependent eosinophil migration. In the present study, we describe the kinetics of the anti-inflammatory activity of L. pacari extract and compare it with dexamethasone. T. canis-infected mice were submitted to different treatment protocols and the cells present in bronchoalveolar space and peritoneal cavity were collected at the end of each treatment period. The results showed that L. pacari extract effectively inhibited eosinophil migration only when the treatment was initiated before the peak of eosinophil migration (1st to 18th; 12th to 18th and 12th to 24th day post-infection). When eosinophil migration was established, administration of L. pacari extract had no effect on it (treatment 18th to 24th day post-infection). Dexamethasone was effective in inhibiting eosinophil migration in all periods studied. We suggest that L. pacari extract can potentially be a natural alternative treatment of eosinophilic diseases.

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OBJECTIVE: Eosinophils and cytokines are implicated in the pathogenesis of allergic diseases. In the present study, we investigate the anti-inflammatory effect of quercetin and isoquercitrin in a murine model of asthma. METHODS: BALB/c mice were immunized (ovalbumin/aluminum hydroxide, s. c.), followed by two intranasal ovalbumin challenges. From day 18 to day 22 after the first immunization, the mice received daily gavages of isoquercitrin (15 mg/kg) or quercetin (10 mg/kg). Dexamethasone (1 mg/kg, s. c.) was administered as a positive control. Leucocytes were analyzed in bronchoalveolar lavage fluid (BALF), blood and pulmonary parenchyma at 24 h after the last ovalbumin challenge. Interleukin-5 (IL-5) was analyzed in BALF and lung homogenates. RESULTS: In animals receiving isoquercitrin or quercetin, eosinophil counts were lower in the BALF, blood and lung parenchyma. Neutrophil counts in blood and IL-5 levels in lung homogenate were lower only in isoquercitrin-treated mice. No alterations in mononuclear cell numbers were observed. CONCLUSION: Quercetin and isoquercitrin are effective eosinophilic inflammation suppressors, suggesting a potential for treating allergies.

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Experimental toxocariasis was used as a model of eosinophil migration. Mice inoculated with 200 Toxocara canis eggs were treated with the leukotriene inhibitor MK886 (1 mg/kg/day). Eosinophils were counted in peripheral blood (PB), peritoneal cavity (PC) and bronchoalveolar lavage fluid (BALF) samples on post-infection days 3, 6, 12, 18, 24 and 36. Eosinophil expression of Mac-1 and VLA-4 was analysed in PB and PC samples. We found that T. canis infection induced systemic eosinophilia from post-infection day 3, peaking on days 6, 12 and 24 in PB, PC and BALF samples respectively. Eosinophilia was more pronounced in PB and PC samples than in BALF samples, and MK886 downregulated eosinophilia to varying degrees in the different sample types. In PB and PC samples, T. canis infection caused early upregulation of Mac-1 with late changes in the VLA-4 profile, whereas MK886 had opposite effects. The distinct time-dependent eosinophilia peaks and differential involvement of leukotrienes in integrin expression demonstrate that, despite the systemic eosinophilia triggered by T. canis infection, inflammatory responses vary by compartment.

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The knowledge of cell-cycle control has shown that the capacity of malignant growth is acquired by the stepwise accumulation of defects in specific genes regulating cell growth. Histologic diagnosis might be improved by a quantitative evaluation of more specific diagnosis biomarkers, which could help to precisely identify pre-malignant and malignant oral lesions. The aim of the present study is to evaluate whether computer-based quantitative assessment of p53, PCNA and Ki-67 immunohistochemical expression, could be used clinically to foresee the risk of oral malignant transformation. This retrospective study was carried out in ninety-five oral biopsies, 27 were classified as fibrous inflammatory hyperplasia, 40 as leukoplakia and 28 as oral squamous cell carcinoma. Sixteen out of the 40 leukoplakia were diagnosed as non-dysplastic leukoplakia, the other 24 being dysplastic leukoplakia, of which 50.0% were classified as moderate to severe dysplasia. Comparison of the four groups of oral tissues showed significant rises in p53 and Ki-67 positivity index, which increased steadily in the order benign, pre-malignant, and malignant. In contrast, it was not possible to relate higher PCNA levels with pre-malignant and malignant oral lesions. We therefore conclude that PCNA immunohistochemistry expression is probably an inappropriate marker to identify oral carcinogenesis, whereas joint quantitative evaluation of p53 and Ki-67, appears to be useful as a tumor marker, providing a pre-diagnostic estimate of the potential for cell-cycle deregulation of the oral proliferate status.

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Infection with oncogenic human papillomavirus (HPV) is considered to be the major risk factor for cervical cancer. Tumor necrosis factor (TNF) is a pluripotent cytokine that plays an important role in inhibiting the action of microbial agents, and TNF microsatellite polymorphisms have been associated with several diseases, including cancer and viral infections. This study analyzed the associations between TNFa to -e microsatellite polymorphisms and the severity of squamous intraepithelial lesions (SIL), according to the presence of the oncogenic HPV16 and HPV18 types. Samples from 146 HPV-positive women with low-grade SIL (LSIL) and high-grade SIL (HSIL) and samples from 101 healthy women were studied. TNF microsatellite polymorphism typing and HPV detection and typing were performed using PCR-amplified DNA hybridized with sequence-specific primers. Data were analyzed by Fisher's exact test using the GENEPOP software. Significant associations were observed between LSIL and the TNFa-8 allele (4/166; P = 0.04), as well as between TNFa-2 with HPV18 only (16/44; P = 0.002) and TNFa-2 with HPV18 coinfection with HPV16 (16/44; P = 0.001). Patients exhibiting the TNFa-2 allele and harboring HPV18, in the presence or absence of coinfection with HPV16, had an increased risk of HSIL occurrence (13/38; P = 0.04; 5/10; P = 0.04) compared to patients with other HPV types. These results suggest that the TNFa-8 allele is associated with increased susceptibility to the occurrence of LSIL and that despite the presence of a high TNF-alpha production allele, the ability of HPV18 to resist the inhibitory effects of TNF-alpha may contribute to the occurrence of infection and consequently to HSIL in women with cervical HPV18 infection.

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