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1.
Article Dans Chinois | WPRIM | ID: wpr-1036487

Résumé

Objective In this study, inbred BALB/c mice infected with the pneumonia virus of mice (PVM) were used to establish an animal model of viral pneumonia, and the changes in the pro-inflammatory alarmin molecule, high mobility group box 1 protein (HMGB1), during PVM infection were observed, as well as the in vivo intervention effects of the HMGB1 inhibitor, glycyrrhizic acid (GA), on PVM-induced lung injury. Methods Three-week-old female BALB/c mice were randomly divided into three groups, each consisting of 6 mice. One group, uninfected by PVM, served as the control group (Control). The other two groups were inoculated intranasally with PVM at a dose of 1×104 50% tissue culture infective dose (TCID50)/25 μL, and subsequently treated with GA saline solution (GA group) or plain saline solution (normal saline, NS group) via gavage for 15 consecutive days. During this period, changes in body weight and appearance were monitored in each group. At the end of the experiment, lung tissue samples were collected from all groups. The distribution of PVM and HMGB1 proteins in the lung tissues was analyzed using hematoxylin-eosin staining and immunohistochemistry. The expression levels of HMGB1 and its Toll-like receptor 4 (TLR-4), advanced glycosylation end-product-specific receptor (AGER), and inflammatory cytokines such as interleukin (IL)-1β, IL-2, and tumor necrosis factor-α (TNF-α) in lung tissues of mice were measured using real time fluorescence quantitative PCR. Results Compared with the Control group, the NS group showed a significant weight loss after 6 days (P<0.05). Histopathological tests revealed pronounced inflammatory lesions in their lungs. Immunohistochemistry results showed that HMGB1 was released from the nucleus to the cytoplasm, and real time fluorescence quantitative PCR results indicated that the expression levels of HMGB1, IL-1β, and IL-2 were significantly upregulated (P<0.05). In the GA group, there was no significant change in the clinical symptoms or body weight. However, compared with the NS group, the pathological damages of lung tissues in the GA group were significantly reduced, and the expression levels of HMGB1, IL-1β, IL-2, and interferon-γ (IFN-γ) in lung tissues were also significantly decreased (P<0.05), although the expression level of AGER was significantly increased (P<0.05).ConclusionPVM infection can cause significant inflammatory pathological lung damages in mice, and GA can effectively alleviate the damages. Its therapeutic effect may be related to the activation of HMGB1 signaling pathway.

2.
Article Dans Chinois | WPRIM | ID: wpr-1028592

Résumé

Objective:To study the effect of rapamycin on the disorder of CD4 + T cell subsets in Graves′ ophthalmopathy(GO) mice, as well as the ophthalmopathy and hyperthyroidism phenotype, providing new possibilities for the treatment of GO. Methods:6-8 weeks old female Balb/c mice were injected intramuscularly with adenovirus expressing the A-subunit of TSHR(A-sub-Ad) 9 times. Rapamycin was given by embedding in the feed(14 ppm). The animals were euthanized 4 weeks after the final injection to obtain blood, spleen cells, thyroid glands, and orbital tissue. TT 4, thyrotropin receptor antibody(TRAb), thyroid, and orbital pathologic changes were detected, and the CD4 + T cell subgroup was evaluated by flow cytometry and immunohistochemistry. Results:After final immunization, the mice showed characteristics of GO: increased retrobulbar fibrosis and retrobulbar adipogenesis that indicated ophthalmopathy, increased autoantibodies, and serum total thyroxin that indicated hyperthyroidism. After the intervention of rapamycin, retrobulbar fibrosis and retrobulbar adipogenesis were significantly improved, and the incidence of ophthalmopathy was reduced from 80%-90% to 20%. Moreover, the increase of total thyroxin was reduced from 80% to 20%, and the metabolic condition and thyroid pathology were also improved. Flow cytometry of the spleen, immunohistochemistry of the thyroid and orbital tissue revealed that GO mice exhibited Th1 dominance in Th1/Th2 balance and reduction of Treg cells. After the intervention of rapamycin, flow cytometry showed that the ratio of Th1 and Th17 cells decreased and the ratio of Th2 and Treg cells increased. Immunohistochemistry of thyroid and orbital tissues also confirmed improvement of Th1/Th2 cell imbalance and Treg cell reduction.Conclusion:GO mouse model showed a significant imbalance of CD4 + T cell subsets, and rapamycin could not only regulate the disorder of CD4 + T cell subsets in GO mice, but also effectively improve the phenotype of ophthalmopathy and hyperthyroidism. Therefore, the imbalance of CD4 + T cell subsets is one of the etiological intervention targets of GO, and rapamycin is a potential intervention mode of GO, which can be further explored by randomized clinical studies in the future.

3.
Article Dans Chinois | WPRIM | ID: wpr-1030693

Résumé

Objective To compare the preparation efficiency of mouse pox and mouse hepatitis antibodies between two substrains of BALB/c and Big-BALB/c (B-BALB/c) mice, and to provide a theoretical basis and reference for the selection of laboratory animals in the preparation of monoclonal antibodies inducedin vivo through hybridoma.Methods Individuals weighing more than 5% of the weight of normal animals at 4 weeks of age (the criterion for late selection is more than 10%) were selected from a population of conventionally bred BALB/c mice and bred individually, and a subline of B-BALB/c mice was prepared after 10 generations of selection. A total of 40 BALB/c mice and 40 B-BALB/c mice aged 10 to 11 weeks, half male and half female, were selected and inoculated with the mousepox monoclonal antibody hybridoma cell line G23 or the murine hepatitis monoclonal antibody hybridoma cell line Y15 pre-treated with liquid paraffin, respectively. Mice ascites containing monoclonal antibodies were obtained by in vivo induction. The antibody titer was tested by indirect ELISA. The mice were grouped based on the sub-strains, gender and inoculation type of hybridoma to analyze the ascites production, antibody titer and antibody production, and to evaluate the antibody preparation efficiency of the two BALB/c mouse sub-strains.ResultsAfter 10 generations of breeding, the body weight of 10-week-old male and female B-BALB/c mice increased by 22.3% and 12.8%, respectively, compared with BALB/c mice of the same age. Compared with BALB/c mice, B-BALB/c mice had better tolerance and adaptation to secondary ascites collection. Compared with BALB/c mice, the ascites production and antibody titer during the preparation of antibodies in B-BALB/c mice were significantly increased, especially in the hybridoma cell line G23 vaccination group (both P<0.000 1) . After inoculation with the hybridoma cell lines G23 or Y15, the average antibody production of B-BALB/c mice (14.99×104 U and 33.22×104 U) was higher than that of BALB/c mice (5.33×104 U and 19.31×104 U) (both P<0.01). After inoculation with hybridoma cell line G23, the average antibody production per unit body weight of B-BALB/c mice (0.55×104 U/g) was higher than that of BALB/c mice (0.23×104 U/g) (P<0.000 1). And the antibody production per unit body weight of female B-BALB/c or BALB/c mice was higher than that of male B-BALB/c or BALB/c mice (bothP<0.01).Conclusion B-BALB/c mice can be used as an alternative to BALB/c mice in the in vivo induction of monoclonal antibody preparation, which can achieve the purpose of reducing the number of experimental animals used, lowering the labor cost, and improving the efficiency of antibody preparation.

4.
International Eye Science ; (12): 1609-1616, 2023.
Article Dans Chinois | WPRIM | ID: wpr-987877

Résumé

AIM:To investigate the neuroprotective effect of 17β-estradiol(E2)on retina light damage in BALB/c and C57BL/6 mice and provide experimental data for the successful construction of a research model for E2 against retinal light damage.METHODS:Totally 40~45 adult female BALB/c or C57BL/6 mice were divided into six groups, 6 for each group: normal control, ovariectomized control, ovariectomized light(mice were stimulated with continuous white light at 10000 lx for 4, 8, 12, 16, and 24h after 14d of ovariectomy), intravitreal administration sham operation, saline and E2 pre-treatment groups(2μL saline or 10-5mol/L E2 were intravitreal injected respectively after 14d of ovariectomy operation and 24h of dark adaptation). The morphological and functional changes of the retina were detected by paraffin section HE staining, TUNEL staining and electroretinogram.RESULTS:In the ovariectomized light group, the thickness of the inner/outer nuclear layer decreased significantly from the 4h stimulation of 10000 lx white light group. Intravitreal administration of E2 significantly inhibited the apoptosis of retinal cells in the two strains of mice(P&#x003C;0.01)and the decrease of amplitudes of a- and b-waves in max-ERG of C57BL/6 mice(P&#x003C;0.05).CONCLUSION:The light loss sensitivity of two strains of mice was different under the same light stimulation. E2 had a protective effect on both morphology and function of the retina in BALB/c mice, and had a significant protective effect on retina function in C57BL/6 mice.

5.
Mem. Inst. Oswaldo Cruz ; 118: e220255, 2023. tab, graf
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1440671

Résumé

BACKGROUND Dengue is a disease caused by dengue virus (DENV-1 through -4). Among the four serotypes, DENV-4 remains the least studied. Acute kidney injury is a potential complication of dengue generally associated with severe dengue infection. OBJECTIVES The goal of this study was to investigate the alterations caused by experimental dengue infection in the kidney of adult BALB/c mice. METHODS In this study, BALB/c mice were infected through the intravenous route with a DENV-4 strain, isolated from a human patient. The kidneys of the mice were procured and subject to histopathological and ultrastructural analysis. FINDINGS The presence of the viral antigen was confirmed through immunohistochemistry. Analysis of tissue sections revealed the presence of inflammatory cell infiltrate throughout the parenchyma. Glomerular enlargement was a common find. Necrosis of tubular cells and haemorrhage were also observed. Analysis of the kidney on a transmission electron microscope allowed a closer look into the necrotic tubular cells, which presented nuclei with condensed chromatin, and loss of cytoplasm. MAIN CONCLUSIONS Even though the kidney is probably not a primary target of dengue infection in mice, the inoculation of the virus in the blood appears to damage the renal tissue through local inflammation.

6.
Braz. J. Pharm. Sci. (Online) ; 59: e21384, 2023. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1505843

Résumé

Abstract Biological activity of boron-containing compounds (BCCs) has been well-known. Growing interest and numerous applications for BCCs have been reported. Boron and boron-containing acids show low acute toxicity in mammals but data on halogenated boroxine (HB) - dipotassium-trioxohydroxytetrafluorotriborate, K2(B3O3F4OH) acute toxicity have not been reported before. This compound, characterized as a potential therapeutic for skin changes, exhibits no observable genotoxicity in doses lower that 0.1 mg/ml in vitro and 55 mg/kg in vivo. It has also been confirmed as an antitumour agent both in vitro and in vivo as well as an inhibitor of enzymes involved in antioxidant mechanisms. The aim of this study was to assess the acute toxicity of HB and to determine the maximum tolerated dose as well as a dose free of any signs of toxicity in different test organisms. Acute toxicity of HB was tested in Sprague-Dawley and Wistar rats and BALB/c mice after single parenteral application of different doses. We determined doses free of any sign of toxicity and LD50 after single dose administration. LD50 of HB ranges from 63 to 75 mg/kg in different test models, meaning that HB shows moderate toxicity


Sujets)
Animaux , Mâle , Femelle , Souris , Rats , Bore/agonistes , Tests de toxicité aigüe/instrumentation , Développement de médicament/instrumentation , Antioxydants/pharmacologie , Produits biologiques/effets indésirables , Techniques in vitro/méthodes
7.
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1360788

Résumé

ABSTRACT The Western-blotting technique was applied to identify antigenic fractions of excretory-secretory Toxocara canis antigen recognized by IgG antibodies throughout an experimental infection in mice challenged by different inocula. Mice were inoculated with 5, 50 and 500 embryonated eggs and serum samples were collected 15, 30, 60, 90 and 120 days post-infection. Serum samples were analyzed using an excretory-secretory Toxocara antigen. Antibodies recognized antigenic fractions from 30 to 90 kDa. The protein fraction of 30-35 kDa was the most frequently recognized regardless of the size of inoculum and the stage of infection represented by the different collection times, but the antigenic recognition was more evident in groups infected with 50 and 500 eggs. This study presents an antigenic panel of the excretory-secretory antigen of T. canis and suggests that the 30-35 kDa antigenic fraction is a promising marker of the infection and should be further explored in future studies on experimental toxocariasis.

8.
Braz. arch. biol. technol ; 65: e22200620, 2022. graf
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1364468

Résumé

Abstract: Asthma is a chronic respiratory disease affecting 300 million people worldwide. It results in several structural changes in the airways, which are minimally accessible in clinical practice. Cell therapy using mesenchymal stromal cells (MSCs) is a promising strategy for treating asthma due to the paracrine activity of MSCs, which influences tissue regeneration and modulates the immune response. Studies using extracellular vesicles (EV) released by MSCs have demonstrated their regenerative properties in animal models. The aim of this study was to evaluate the potential of EVs isolated from human bone marrow MSCs (hBM-MSCs) to control lung tissue remodeling in ovalbumin-induced allergic asthma in Balb/c mice. We isolated hBM-MSCs from a single donor, expanded and characterized them, and then isolated EVs. Asthma was induced in 43 male Balb/c mice, divided into four groups: control, asthmatic (AS), asthmatic plus systemic EVs (EV-S), and asthmatic plus intratracheal EVs (EV-IT). Upon completion of asthma induction, animals were treated with EVs either locally (EV-IT) or intravenously (EV-S). Seven days after, we performed bronchoalveolar lavage (BAL) and the total nuclear cells were counted. The animals were euthanized, and the lungs were collected for histopathological analysis of the airways. The EV-S group showed improvement in only the total BAL cell count compared with the AS group, while the EV-IT group showed significant improvement in almost all evaluated criteria. Therefore, we demonstrate that the local application of EVs derived from hBM-MSCs may be a potential treatment in controlling asthma.

9.
Rev. peru. med. exp. salud publica ; 38(3): 424-433, jul.-sep. 2021. graf
Article Dans Espagnol | LILACS | ID: biblio-1357372

Résumé

RESUMEN Objetivo: Evaluar la toxicidad de tres chalconas sintéticas administradas por vía intraperitoneal en ratones BALB/c. Materiales y métodos: La dosis letal media (DL50) se estimó por el método Up-and-Down de Dixon. La toxicidad subcrónica de las chalconas se evaluó a 20 y 40 mg/kg por 21 días. Se evaluó el efecto tóxico a nivel de comportamiento, fisiológico, bioquímico e histológico. Resultados: La chalcona 43 generó moco en las heces, daño visceral (hígado) y alteración en el coeficiente de órganos (riñón, p = 0,037 y cerebro, p = 0,008) en comparación con el grupo control. Además, en el análisis histológico se observó que esta chalcona produjo edema, inflamación y necrosis en los órganos evaluados, aunque no hubo diferencia significativa con el control. Todos los parámetros bioquímicos no difirieron significativamente entre los grupos de tratamiento a dosis de 40 mg/kg y el control. Conclusiones: La DL50 para las tres chalconas fue superior a 550 mg/kg de peso corporal. Las chalconas 40 y 42 son relativamente no tóxicas. Ambas pueden considerarse seguras para la aplicación vía intraperitoneal en ratones BALB/c y, en consecuencia, son posibles candidatas para ser usadas en el tratamiento contra las leishmaniosis.


ABSTRACT Objective: To evaluate the toxicity of three synthetic chalcones administered intraperitoneally to BALB/c mice. Materials and methods: The median lethal dose (LD50) was estimated by Dixon's Up-and-Down method. Subchronic toxicity of chalcones was evaluated at 20 and 40 mg/kg for 21 days. Behavioral, physiological, biochemical, and histological toxic effects were evaluated. Results: Chalcone 43 produced mucus in feces, visceral damage (liver) and alterations in organ coefficient (kidney, p = 0.037 and brain, p = 0.008) when compared to the control group. In addition, histological analysis showed that this chalcone produced edema, inflammation and necrosis in the evaluated organs, although there was no significant difference with the control. None of the biochemical parameters differed significantly between the treatment groups at 40 mg/kg dose and the control. Conclusions: The LD50 for all three chalcones was greater than 550 mg/kg of body weight. Chalcones 40 and 42 were found to be relatively non-toxic. Both can be considered safe for intraperitoneal application in BALB/c mice and, consequently, are potential candidates for use in the treatment of leishmaniasis.


Sujets)
Animaux , Souris , Chalcones , Toxicité , Souris de lignée BALB C , Chalcone , Tests de toxicité subchronique , Développement de médicament , Leishmania , Souris
10.
Braz. j. biol ; 80(3): 489-496, July-Sept. 2020. graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1468409

Résumé

The main objective of current study was to investigate the chemopreventive and chemotherapeutic activity of Artemisia vulgaris extract on diethylnitrosoamine induced hepatocarcinogenesis in Balb C mice. Diethylnitrosoamine (DEN: 0.9%) was prepared to induce hepatocarcinoma in Balb C mice. The extract Artemisia vulgaris (AV) was prepared by maceration technique. Mice were classified into four groups as follows: Group 1 a control group (N=7) received saline solution (3.5 l/mg), group 2 (N=14) received diethylnitrosoamine (3.5 l/mg) intraperitoneally once in a week for eight consecutive weeks, group 3 (N=7) received only plant extract (AV: 150 mg/kg (Body weight) once in a week, while group 4 (N=7) was given in combination of diethylnitrosoamine (3.5 l/mg) and plant extract (AV: 150 mg/kg (body weight). After eight weeks of DEN administration, mice of group 2 were divided into two subgroups containing seven mice each; subgroup 1 was sacrificed while subgroup 2 was treated with plant extract only (150 mg/kg (body weight)) once in a week for eight consecutive weeks. The DEN injected mice significant decline in levels of albumin with concomitant significant elevations such as aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alpha feto protein, gamma glutamyl transferase, 5 nucleotidase, glucose-6-phosphate dehydrogenase and bilirubin. The administration of A. vulgaris significantly decreased the DEN induced hepatotoxicity. Present study revealed the potential anti-cancerous nature of Artemisia vulgaris, both in case of chemopreventive and post-treatment of A. vulgaris. Further studies are needed to explore the mechanism of prevention and therapy.


O objetivo principal do presente estudo foi investigar as atividades quimiopreventiva e quimioterápica do extrato de Artemisia vulgaris em hepatocarcinogênese induzida por dietilnitrosoamina (DEN) em camundongos Balb C. Dietilnitrosoamina (DEN: 0,9%) foi preparada para induzir hepatocarcinoma em camundongos da linhagem Balb C. O extrato de A. vulgaris (AV) foi preparado pela técnica de maceração. Os camundongos foram classificados em quatro grupos conforme os seguintes: grupo 1, grupo controle (N=7) recebeu solução salina (3,5 µl/mg); grupo 2 (N=14) recebeu dietilnitrosoamina (3,5 µl/mg) por via intraperitoneal uma vez por semana durante oito semanas consecutivas; grupo 3 (N=7) recebeu apenas o extrato vegetal (AV: 150 mg/kg (peso corporal) uma vez por semana; enquanto no grupo 4 (N=7) foi administrado uma combinação de dietilnitrosoamina (3,5 l/mg) com extrato vegetal (AV: 150 mg/kg (peso corporal). Após oito semanas de administração de DEN, os camundongos do grupo 2 foram divididos em dois subgrupos, contendo sete camundongos cada um; no subgrupo 1, os animais foram sacrificados, enquanto no subgrupo 2, os animais foram tratados apenas com extrato vegetal (150 mg/kg (peso corporal)) uma vez por semana durante oito semanas consecutivas. Os camundongos nos quais foram injetados DEN apresentaram declínio significativo nos níveis de albumina, mas elevações significativas concomitantes de: aspartato aminotransferase, alanina aminotransferase, lactato desidrogenase, alfa-fetoproteína, gama-glutamiltransferase, 5 nucleotidase, glicose-6-fosfato desidrogenase e bilirrubina. A administração de A. vulgaris diminuiu significativamente a hepatotoxicidade induzida pelo DEN. O presente estudo apresentou a potencialidade anticancerosa da A. vulgaris, tanto nos casos de quimioprevenção quanto no pós-tratamento da A. vulgaris. Mais estudos são necessários para explorar o mecanismo de prevenção e a terapia.


Sujets)
Artemisia/effets des médicaments et des substances chimiques , Artemisia/composition chimique , Souris , Carcinogenèse , N-Éthyl-N-nitroso-éthanamine , Préparations pharmaceutiques
11.
Braz. j. biol ; 80(3): 484-496, July-Sept. 2020. graf
Article Dans Anglais | LILACS | ID: biblio-1132402

Résumé

Abstract The main objective of current study was to investigate the chemopreventive and chemotherapeutic activity of Artemisia vulgaris extract on diethylnitrosoamine induced hepatocarcinogenesis in Balb C mice. Diethylnitrosoamine (DEN: 0.9%) was prepared to induce hepatocarcinoma in Balb C mice. The extract Artemisia vulgaris (AV) was prepared by maceration technique. Mice were classified into four groups as follows: Group 1 a control group (N=7) received saline solution (3.5 μl/mg), group 2 (N=14) received diethylnitrosoamine (3.5 μl/mg) intraperitoneally once in a week for eight consecutive weeks, group 3 (N=7) received only plant extract (AV: 150 mg/kg (Body weight) once in a week, while group 4 (N=7) was given in combination of diethylnitrosoamine (3.5 μl/mg) and plant extract (AV: 150 mg/kg (body weight). After eight weeks of DEN administration, mice of group 2 were divided into two subgroups containing seven mice each; subgroup 1 was sacrificed while subgroup 2 was treated with plant extract only (150 mg/kg (body weight)) once in a week for eight consecutive weeks. The DEN injected mice significant decline in levels of albumin with concomitant significant elevations such as aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alpha feto protein, gamma glutamyl transferase, 5 nucleotidase, glucose-6-phosphate dehydrogenase and bilirubin. The administration of A. vulgaris significantly decreased the DEN induced hepatotoxicity. Present study revealed the potential anti-cancerous nature of Artemisia vulgaris, both in case of chemopreventive and post-treatment of A. vulgaris. Further studies are needed to explore the mechanism of prevention and therapy.


Resumo O objetivo principal do presente estudo foi investigar as atividades quimiopreventiva e quimioterápica do extrato de Artemisia vulgaris em hepatocarcinogênese induzida por dietilnitrosoamina (DEN) em camundongos Balb C. Dietilnitrosoamina (DEN: 0,9%) foi preparada para induzir hepatocarcinoma em camundongos da linhagem Balb C. O extrato de A. vulgaris (AV) foi preparado pela técnica de maceração. Os camundongos foram classificados em quatro grupos conforme os seguintes: grupo 1, grupo controle (N=7) recebeu solução salina (3,5 µl/mg); grupo 2 (N=14) recebeu dietilnitrosoamina (3,5 µl/mg) por via intraperitoneal uma vez por semana durante oito semanas consecutivas; grupo 3 (N=7) recebeu apenas o extrato vegetal (AV: 150 mg/kg (peso corporal) uma vez por semana; enquanto no grupo 4 (N=7) foi administrado uma combinação de dietilnitrosoamina (3,5 μl/mg) com extrato vegetal (AV: 150 mg/kg (peso corporal). Após oito semanas de administração de DEN, os camundongos do grupo 2 foram divididos em dois subgrupos, contendo sete camundongos cada um; no subgrupo 1, os animais foram sacrificados, enquanto no subgrupo 2, os animais foram tratados apenas com extrato vegetal (150 mg/kg (peso corporal)) uma vez por semana durante oito semanas consecutivas. Os camundongos nos quais foram injetados DEN apresentaram declínio significativo nos níveis de albumina, mas elevações significativas concomitantes de: aspartato aminotransferase, alanina aminotransferase, lactato desidrogenase, alfa-fetoproteína, gama-glutamiltransferase, 5' nucleotidase, glicose-6-fosfato desidrogenase e bilirrubina. A administração de A. vulgaris diminuiu significativamente a hepatotoxicidade induzida pelo DEN. O presente estudo apresentou a potencialidade anticancerosa da A. vulgaris, tanto nos casos de quimioprevenção quanto no pós-tratamento da A. vulgaris. Mais estudos são necessários para explorar o mecanismo de prevenção e a terapia.


Sujets)
Animaux , Lapins , Carcinome hépatocellulaire , Artemisia , Tumeurs du foie , Extraits de plantes , N-Éthyl-N-nitroso-éthanamine , Carcinogenèse , Souris de lignée BALB C
12.
Article Dans Chinois | WPRIM | ID: wpr-841538

Résumé

Objective: To induce the atopic dermatitis (AD) by 2, 4-dinitrobenzene (DNCB) in the BALB/c mice, and to explore the possible mechanism of DNCB as hapten to induce AD. Methods: A total of 12 BALB/c mice were randomly divided into control group (n = 6) and AD model group (n = 6). The dorsal skin of the mice in AD model group was sensitized by 1.0% DNCB at days 1, 4, and 7 and the back skin of the left ears were challenged by 0. 5% DNCB at days 14, 17, 19, 22, 24, 27, and 29. The mice in control group were given substrate solution with the same volume at the same time points. The inflammation scores of the skin tissue of the mice in two groups were evaluated, the appearance changes of the ear skin of the mice in two groups were observed, the pathomorphology of the skin tissue in left ear of the mice in two groups were observed by HE staining and toluidine blue staining, the epidermal thickness of the skin tissue at lesion site of the mice in two groups was measured, and the number of mast cells in the skin tissue at lesion site of the mice in two groups was counted; the expression levels of interleukin-4 (IL-4) in the skin tissue at lesion site of the mice in two groups was detected by immunohistochemistry staining, and the levels of serum IgE was detected by ELISA method. Results: The inflammation score of the mice in AD model group was higher that in control group (P < 0. 01). The skin tissue in left ear of the mice in AD model presented as redness swelling and hardening accompaning with abnormal scratching marks; the epidermal thickness, the number of mast cells, the expression level of IL-4 in skin tissue at lesion site and the level of serum IgE of the mice in AD model group were all increased compared with control group (P < 0. 05 or P < 0. 01). Conclusion: The AD mouse can be successfully induced by 1. 0% DNCB for sensitizing and 0. 5% DNCB for chllenging in the BALB/c mice, and its mechanism may be related with the increasing of IL-4 expression level in skin tissue and IgE level in serum.

13.
Braz. j. biol ; 79(4): 629-638, Nov. 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1001489

Résumé

Abstract Background Hepatocellular carcinoma is the most frequent primary malignancy of liver and accounts for as many as one million deaths worldwide in a year. Objectives The aim of the present study was to evaluate the anti-cancerous efficiency of Bergenia ciliata rhizome against diethylnitrosoamine induced hepatocarcinogenesis in Balb C mice. Methods One percent diethylnitrosoamine was prepared by using 99 ml of normal saline NaCl (0.9 percent) solution to which was added 1 ml of concentrated diethylnitrosoamine (DEN) solution (0.01 μg/μl). Extract of Bergenia ciliata was prepared by maceration technique. Mice were classified into four groups as follows: Group 1 a control group (N=7) received saline solution (3.5 μl/mg), group 2 (N=14) received diethylnitrosoamine (3.5 μl/mg) intraperitoneally once in a week for eight consecutive weeks, group 3 (N=7) received plant extract (150 mg/kg (Body weight)) once in a week, while group 4 (N=7) was given combination of diethylnitrosoamine (3.5 μl/mg) and plant extract (150 mg/kg (Body weight)). After eight weeks of DEN induction group 2 mice were divided into two subgroups containing seven mice each, subgroup 1 was sacrificed while subgroup 2 was treated with plant extract (150 mg/kg (Body weight)) once in a week for eight consecutive weeks. Results The model of DEN injected hepatocellular carcinomic (HCC) mice elicited significant decline in levels of albumin with concomitant significant elevations in tumor markers aspartate aminotransferase, alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alpha feto protein (AFP), gamma glutamyl transferase (Y-GT), 5 nucleotidase (5NT), glucose-6-phosphate dehydrogenase (G6PDH) and bilirubin. The intraperitoneal administration of B. ciliata as a protective agent, produced significant increase in albumin levels with significant decrease in the levels of tumor markers aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alpha feto protein (AFP), gamma glutamyl transferase (Y-GT), 5 nucleotidase (5NT), glucose-6-phosphate dehydrogenase (G6PDH) and bilirubin. Conclusion Bergenia ciliata has potent antioxidant activity, radical scavenging capacity and anticancerous properties. Bergenia ciliata extracts may provide a basis for development of anti-cancerous drug.


Resumo Antecedentes O carcinoma hepatocelular é a neoplasia primária mais frequente do fígado e é responsável por até um milhão de mortes em todo o mundo em um ano. Objetivos O objetivo do presente estudo foi avaliar a eficiência anticancerígena do rizoma de Bergenia ciliata contra a hepatocarcinogênese induzida por dietilnitrosoamina em camundongos balb c. Métodos Um por cento de dietilnitrosoamina foi preparado usando 99 ml de solução salina normal (0,9 por cento) à qual foi adicionado 1 ml de solução concentrada de dietilnitrosoamina (DEN) (0,01 μg / μl). O extrato de Bergenia ciliata foi preparado pela técnica de maceração. Os ratos foram classificados em quatro grupos: Grupo 1 grupo controle (N = 7) recebeu solução salina (3,5 mL / mg), grupo 2 (N = 14) recebeu dietilnitrosoamina (3,5 mL / mg) por via intraperitoneal uma vez por semana para oito semanas consecutivas, o grupo 3 (N = 7) recebeu extrato vegetal (150 mg / kg (peso corporal)) uma vez por semana, enquanto o grupo 4 (N = 7) recebeu combinação de dietilnitrosoamina (3,5 μl / mg) e extrato (150 mg / kg (peso corporal). Após oito semanas do grupo de indução DEN 2 ratos foram divididos em dois subgrupos contendo sete ratos cada, subgrupo 1 foi sacrificado enquanto subgrupo 2 foi tratado com extrato vegetal (150 mg / kg)) uma vez por semana durante oito semanas consecutivas. Resultados O modelo de camundongos hepatocelulares carcinômicos (CHC) injetados com DEN provocou declínio significativo nos níveis de albumina com elevações significativas concomitantes nos marcadores tumorais: aspartato aminotransferase, alanina aminotransferase (ALT), lactato desidrogenase (LDH), proteína alfa feto (AFP), gama glutamiltransferase (Y-GT), 5 nucleotidase (5NT), glicose-6-fosfato ehidrogenase (G6PDH) e bilirrubina. A administração intraperitoneal de B. ciliata como agente protetor produziu um aumento significativo nos níveis de albumina com uma diminuição significativa nos níveis dos marcadores tumorais: aspartato aminotransferase, alanina aminotransferase (ALT), lactato desidrogenase (LDH), proteína alfa feto (AFP), gama glutamiltransferase (Y-GT), 5 nucleotidase (5NT), glicose-6-fosfato desidrogenase (G6PDH) e bilirrubina. Conclusão Bergenia ciliata possui atividade antioxidante potente, capacidade de eliminação de radicais livres e propriedades anticancerígenas. Extratos de Bergenia ciliata podem fornecer uma base para o desenvolvimento de drogas anti-cancerígenas.


Sujets)
Animaux , Mâle , Rats , Carcinome hépatocellulaire/induit chimiquement , Carcinome hépatocellulaire/anatomopathologie , N-Éthyl-N-nitroso-éthanamine/pharmacologie , Tumeurs du foie/induit chimiquement , Tumeurs du foie/anatomopathologie , Tumeurs expérimentales/induit chimiquement , Extraits de plantes/pharmacologie , Saxifragaceae , Agents alcoylants/pharmacologie , Souris de lignée BALB C
14.
Arq. gastroenterol ; 56(2): 191-196, Apr.-June 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1019453

Résumé

ABSTRACT BACKGROUND: Colorectal cancer is one of the most prevalent pathologies. Its prognosis is linked to the early detection and treatment. Currently diagnosis is performed by histological analysis from polyp biopsies, followed by morphological classification. Kudo's pit pattern classification is frequently used for the differentiation of neoplastic colorectal lesions using hematoxylin-eosin stained samples. Few articles have reported this classification with image software processing, using exogenous markers over the samples. The processing of autofluorescence images is an alternative that could allow the characterization of the pits from the crypts of Lieberkühn, bypassing staining techniques. OBJECTIVE: Processing and analysis of widefield autofluorescence microscopy images obtained by fresh colon tissue samples from a murine model of colorectal cancer in order to quantify and characterize the pits morphology by measuring morphology parameters and shape descriptors. METHODS: Adult male BALB/cCmedc strain mice (n=27), ranging from 20 to 30 g, were randomly assigned to four and five groups of treated and control animals. Colon samples were collected at day zero and at fourth, eighth, sixteenth and twentieth weeks after treatmentwith azoxymethane. Two-dimensional (2D) segmentation, quantification and morphological characterization of pits by image processing applied using macro programming from FIJI. RESULTS: Type I is the pit morphology prevailing between 53 and 81% in control group weeks. III-L and III-S types were detected in reduced percentages. Between the 33 and 56% of type I was stated as the prevailing morphology for the 4th, 8th and 20th weeks of treated groups, followed by III-L type. For the 16th week, the 39% of the pits was characterized as III-L type, followed by type I. Further, pattern types as IV, III-S and II were also found mainly in that order for almost all of the treated weeks. CONCLUSION: These preliminaries outcomes could be considered an advance in two-dimensional pit characterization as the whole image processing, comparing to the conventional procedure, takes a few seconds to quantify and characterize non-pathological colon pits as well as to estimate early pathological stages of colorectal cancer.


RESUMO CONTEXTO: O câncer colorretal é uma das patologias mais prevalentes. Seu prognóstico é ligado à detenção e ao tratamento precoces. Atualmente o diagnóstico é realizado por análise histológica de biópsias de pólipo, seguida de classificação morfológica. A classificação de padrões de Kudo é frequentemente utilizada para a diferenciação de lesões colorretais neoplásicas usando amostras coradas por hematoxilina-eosina. Poucos artigos relatam esta classificação com utilização de processamento por software de imagem, utilizando marcadores exógenos sobre as amostras. O processamento de imagens de autofluorescência é uma alternativa que pode permitir a caracterização do padrão das criptas de Lieberkühn, contornando técnicas de coloração. OBJETIVO: Analisar, quantificar e caracterizar a morfologia do padrão das criptas medindo os parâmetros morfológicos e descritores de forma, através do processamento e análise de imagens de microscopia de autofluorescência de campo de Widefield obtidas em amostras de tecido de cólon fresco a partir de um modelo murino de câncer colorretal. MÉTODOS: Camundongos machos adultos BALB/cCmedc (n=27), variando de 20 a 30 g, foram distribuídos aleatoriamente em quatro e cinco grupos de animais tratados e de controle. As amostras de cólon foram coletadas no dia zero e na 4ª, 8ª, 16ª e 20ª semanas após o tratamento com azoxometano. Segmentação bidimensional (2D), quantificação e caracterização morfológica do padrão das criptas por processamento de imagem aplicados utilizando programação macro de FIJI. RESULTADOS: O tipo I é a morfologia da cripta prevalente entre 53% e 81% semanas do grupo controle. Os tipos III-L e III-S foram detectados em porcentagens reduzidas. A morfologia do tipo I entre os 33% e 56% foi constatada como a predominante para as 4ª, 8ª e 20ª semanas de grupos tratados, seguidos pelo tipo III-L. Para a 16ª semana, os 39% dos padrões das criptas foram caracterizados como tipo III-L, seguidos pelo tipo I. Além disso, os tipos de padrão como IV, III-S e II também foram encontrados principalmente nessa ordem para quase todas as semanas tratadas. CONCLUSÃO: Estes resultados preliminares podem ser considerados um avanço na caracterização bidimensional da cripta como um processamento integral da imagem, comparando-se ao procedimento convencional; demora-se alguns segundos a mais para quantificar e caracterizar pontos não-patológicos, bem como para estimar estágios patológicos precoces do câncer colorretal.


Sujets)
Animaux , Mâle , Tumeurs colorectales/imagerie diagnostique , Polypes coliques/imagerie diagnostique , Microscopie de fluorescence , Tumeurs colorectales/anatomopathologie , Polypes coliques/anatomopathologie , Modèles animaux de maladie humaine , Souris de lignée BALB C
15.
Chinese Pharmacological Bulletin ; (12): 235-240, 2019.
Article Dans Chinois | WPRIM | ID: wpr-857289

Résumé

Aim: To explore the therapeutic effects of Dendrobium officinale extract on mice with ulcerative colitis(UC) and its mechanism. Methods: The mice were treated with 4% DSS to induce the UC model. The signs or symptom changes of mice were observed and recorded. Then the scores of disease activity index (DAI) during the days of modeling and drug treatment were also evaluated, and the colon tissues were taken as samples. The samples were used for general and microscopic evaluation, the expression of MPO was detected by Western blot, and the expressions of IFN-γ and TNF-α mRNA were measured by qPCR. Meanwhile, the concentrations of serum IFN-γ, TNF-α in mice were also determined by ELISA. Results: As compared with model group, the colon length of mice treated with Dendrobium officinale extract was longer. The DAI score, histological damage score were reduced (P <0. 05 or P <0. 01); the concentrations of IFN-7 and TNF-α inflammatory cytokines in serum decreased (P < 0. 05); the expressions of IFN-γ mRNA and MPO protein in the colon tissue significantly decreased compared with model group (P < 0. 05). Conclusions: Dendrobium officinale extract could treat DSS-induced UC of BALB/c mice. The anti-UC mechanism of Dendrobium officinale extract can be attributed to its ability to reduce the release of IFN-γ and TNF-α and downregulate the expressions of IFN-γ, TNF-α and MPO, to block the amplification effect of inflammation and to achieve its therapeutic effects.

16.
Article Dans Chinois | WPRIM | ID: wpr-756210

Résumé

Objective To compare the changes in IFN-γ, IL-4, IL-10 and IL-1β expression at mRNA level in gastric mucosae of BALB/c, C57BL/6 and nude mice at different stages of Helicobacter heilmannii ( H. heilmannii) infection, and to investigate the types of induced immune responses. Methods Each kind of mice was randomly divided into two groups: infection ( n=30 ) and control ( n=6 ) groups. Those in the infection groups were intragastrically inoculated with H. heilmannii strains to establish long-term stable mouse infection models. Gastric mucosa tissues were collected at weeks 4, 8, 12, 24 and 36 and ana-lyzed by semi-quantitative RT-PCT to detect the expression of IFN-γ, IL-4, IL-10 and IL-1βat mRNA lev-el. Results In the early stage of infection (weeks 4-12), INF-γ, IL-4, IL-10, and IL-1β expression at mRNA level in the gastric mucosae of BALB/c and C57BL/6 mice were significantly increased compared with those of the control groups (P<0. 05). IL-4, IL-10 and IFN-γexpression peaked at weeks 8-12, while IL-1βexpression reached the peak at week 4. After 12 weeks, IFN-γexpression at mRNA level in BALB/c mice was significantly decreased, but showed no significant change in C57BL/6 mice. IL-4 expression at mRNA level in C57BL/6 mice at the late stage of infection (week 36) was lower than that in the correspond-ing control group (P<0. 05). Expression of IFN-γ, IL-4, IL-10 and IL-1β at mRNA level in nude mice were all higher than those in the control group, and there were significant differences in IL-1βand IL-4 ex-pression between groups (P<0. 05). Conclusions Expression of cytokines in H. heilmannii-infected mice increased over time. IFN-γ-mediated Th1 immune responses were the predominant immunity induced by H. heilmannii infection. Immune responses to H. heilmannii infection varied with the kinds of mice. C57BL/6 mice showed mainly Th1 cell immune responses, while Th1/Th2 mixed immune responses were induced in BALB/c mice.

17.
International Journal of Pediatrics ; (6): 140-143,封3, 2019.
Article Dans Chinois | WPRIM | ID: wpr-742834

Résumé

Objective To detect the expression of Nrf2 in mice with viral myocarditis and to investigate the changes and effects of Nrf2 after puerarin (Pue) treatment.Methods A total of 130 BALB/C male mice aged 4 weeks were randomly divided into control group,VMC group,Nrf2 activator group and Pue group (20 mice in each group) with different concentrations.The models were made with Coxsackie B3 virus (CVB3).The mice were sacrificed on day 0,4,7,14 and 28 respectively,and blood and myocardial samples were harvested.Cardiomyocyte apoptosis was detected by flow cytometry.The expression changes of Nrf2,HO-1,Fas,TGF-beta 1 mRNA were detected by real-time PCR and Western blot respectively.Statistical software SPSS19.0 was used to analyze the results.The measurement data was expressed mean ± standard deviation.The paired samples were tested with mean t test.The group data were analyzed with two-way ANOVA.A P value of less than 0.05 was considered to indicate statistical significance.Correlation analysis was performed with Spearman's correlation test.Results Nrf2 mRNA and Nrf2 protein were expressed in all groups.The correlations between Nrf2 and HO-1,Fas and TGF-beta-1 were analyzed according to CPDT or Pue,and the results were consistent with each other.It showed that the relationship between Nrf2 and HO-1,Fas and TGF-beta-1 did not change with intervention measures.The transcription and protein expression of HO1 in CPDT and Pue groups were significantly increased,and were positively correlated with Nrf2 (r =0.969,P <0.01).At a certain dose gradient (< 45 mg/kg),the transcription and protein expression of HO-1 were dose-dependent;the decreased cardiomyocyte apoptosis was observed in both CPDT and Pue group,while Nrf2 and Fas were negatively correlated (r =-0.968,P < 0.01);at a certain dose gradient,the expression of TGF-beta 1 in CPDT and Pue group decreased with the increase of dose,and Nrf2 and TGF-beta 1 were negatively correlated (r =-0.753,P < 0.01).Conclusion The increased expression of Nrf2 in VMC is involved in the occurrence and development of VMC.Nrf2 has antioxidant effect in VMC by up-regulating the antioxidant enzyme HO-1,has the anti-myocardial APO effect by inhibiting the Fas/FasL signaling pathway,and inhibits myocardial fibrosis by suppressing the expression of TGF-beta 1 protein and transcription.The therapeutic effect of Pue on VMC is to activate Nrf2 to produce antioxidant,anti-apoptotic and anti-fibrotic effects.

18.
Mem. Inst. Oswaldo Cruz ; 114: e180535, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1002683

Résumé

BACKGROUND Topical treatment of New World cutaneous leishmaniasis can be affected by bacterial coinfection, hyperkeratosis, and transdermal drug delivery. OBJECTIVE The aim of this work was to evaluate the therapeutic response and safety of the topical, sequential use of antiseptic, keratolytic, and pentamidine isethionate (PMD) creams (3-PACK kit) on CL-infected BALB/c mice. METHODS A 0.5% chlorhexidine solution (CGH), 10% salicylic acid (SA), and 3% or 6% PMD were used as antiseptic, keratolytic, and antileishmanial drugs, respectively. During the first seven days, antiseptic, followed by 10% SA gel and PMD cream, were applied topically. Subsequently, treatment was performed only with the antiseptic and PMD creams. Skin irritation, reduction of lesion size (mm2), and parasitic load were observed until 30 days of treatment were completed. FINDINGS The 3-PACK treatment using 6% PMD induced a complete lesion reduction in 3/6 mice and a partial reduction in 1/6 mice, with no parasites observed. In contrast, CGH and SA alone, along with the vehicle, were not effective (p < 0.05). Moderate to severe erythema was observed at the application site. MAIN CONCLUSION The topical 3-PACK using 6% PMD was 67% effective in the treatment of CL by Leishmania (Viannia) braziliensis. Currently, work is ongoing to improve PMD isethionate formulation and to determine a dose-response.


Sujets)
Pentamidine/usage thérapeutique , Leishmania brasiliensis/parasitologie , Leishmaniose cutanée/prévention et contrôle , Kératolytiques , Souris de lignée BALB C , Anti-infectieux locaux/usage thérapeutique
19.
Braz. J. Pharm. Sci. (Online) ; 55: e17231, 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1039057

Résumé

Anesthetics are an indispensable prerequisite for surgical intervention and pharmacological animal studies. The objective of present study was to optimize the dose of ketamine (K) and xylazine (X) along with atropine sulfate (A) in order to achieve surgical tolerance in BALB/c mice. Several doses of ketamine (100, 150, 200 mg/kg) and xylazine (10, 15, 20 mg/kg) were mixed and combination of nine doses (K/X: 100/10, 100/15, 100/20, 150/10, 150/15, 150/20, 200/10,200/15,200/20) were evaluated (n=9 per combination). A constant dose of atropine (0.05 mg/kg) was also used to counter side effect. Time-related parameters were evaluated on the basis of reflexes. KX at dose 200/20 mg/kg produced surgical tolerance in all nine mice with duration 55.00±6.87 minutes. The induction time 0.97±0.09 minutes, sleeping time 90.67±5.81 minutes and immobilization time (102.23±6.83 minutes) were significantly higher than all combination. However, this combination was considered unsafe due to 11 % mortality. While, KX at dose 200/15 mg/kg results in none of the mortality, so was considered as safe. Moreover, this combination produces surgical tolerance in 89 % mice with duration (30.00±7.45 minutes). It was concluded that KX at dose 200/15 mg/kg along with atropine 0.05 mg/kg is safe for performing surgical interventions in BALB/c mice.


Sujets)
Animaux , Mâle , Souris , Xylazine/agonistes , Kétamine/agonistes , Atropine/antagonistes et inhibiteurs , Anesthésie/classification
20.
Rev. Univ. Ind. Santander, Salud ; 51(1): 33-42, Diciembre 22, 2018. tab, graf
Article Dans Espagnol | LILACS | ID: biblio-1003153

Résumé

Resumen Introducción: La diversidad de las formas clínicas de la leishmaniasis del Nuevo Mundo (desde formas cutáneas localizadas a diseminadas o formas mucosas) causada por especies del subgénero Viannia podría inferir en la eficacia de los tratamientos tópicos. El objetivo del presente trabajo fue determinar las características de la leishmaniasis cutánea producida por infecciones con Leishmania (V.) braziliensis y L.(V.) panamensis en ratones BALB/c y la eficacia de un mismo tratamiento tópico. Materiales y métodos: Después de la infección con cada una de las especies se realizó seguimiento de las lesiones determinando su tamaño (mm ) y características macroscópicas, cada siete días por 150 días. Las características histopatológicas (en lesiones y órganos) fueron determinadas 70, 106 y 150 días post-infección y la eficacia de un tratamiento tópico (cura de lesión y parasitológica) fue determinada después del tratamiento con un gel de miltefosina aplicado una vez al día por 20 días sobre las lesiones. Resultados: Se observó un aumento del tamaño de las lesiones en ambos grupos de ratones, sin embargo, un mayor tamaño de las lesiones e intensidad de la respuesta inflamatoria con menos alteraciones epidérmicas fue encontrada en los ratones infectados con L. (V.) braziliensis. En ningún grupo se encontraron parásitos en órganos (nódulos, bazo e hígado) ni diferencias en la efectividad del tratamiento tópico utilizado. Conclusión: La eficacia del tratamiento tópico utilizado no fue afectada por las diferencias macro y microscópicas encontradas en la leishmaniasis producida por las dos especies de Leishmania evaluadas.


Abstract Introduction: The efficacy of topical treatments could be affected by the diversity of clinical forms (localized or disseminated cutaneous forms, mucosal forms) of New World-leishmaniasis caused by species of Leishmania from the subgenus Viannia. The aim of this study was to determine the cutaneous leishmaniasis features produced after infection with Leishmania (V.) braziliensis and L. (V.) panamensis in BALB/c mice and to determine the efficacy of one topical treatment. Materials and methods: Cutaneous leishmaniasis lesions were followed up after infection determining their lesion-size (mm2) and other macroscopic characteristics every 7 days for 150 days. Histopathological patterns (in lesions and organs) were determined 70, 106 and 150 days post-infection and the efficacy (lesion and parasitological cure) of miltefosine gel applied topical once a day for 20 days was determined. Results: An increase of size-lesions was observed in both groups of mice, however, a higher lesion- size and inflammatory response but lower epidermal changes were observed in L. (V.) braziliensis compared with L. (V.) panamensis infected ones. No parasites were observed in organs (nodules, spleen and liver) and no differences were observed in the effectiveness of the used topical treatment. Conclusion: The efficacy of the topical treatment used was not affected by the macro and microscopic differences produced after infection by the two Leishmania species evaluated.


Sujets)
Animaux , Leishmania brasiliensis , Leishmania guyanensis , Souris de lignée BALB C , Anti-infectieux locaux
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