scholarly journals Inhibition ofPasteurella multocidaAdhesion to Rabbit Respiratory Epithelium Using Lectins

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Magda Patricia Carrillo ◽  
Nhora María Martinez ◽  
María del Pilar Patiño ◽  
Carlos Arturo Iregui

This study aimed to evaluate the ability of a panel of lectins to inhibit the ability ofPasteurella multocidato adhere to and affect the rabbit respiratory epithelium. Nasal septa from rabbit fetuses were cultured with various lectins before the addition ofP. multocida. The percentage of bacteria adhering to the epithelium was evaluated semiquantitatively by indirect immunoperoxidase (IIP) staining. The goblet cells (GCs) were counted in semithin sections stained with toluidine blue and served as the main morphological criterion to evaluate the inhibitory effect of the lectins. The lectins PNA, WGA, RCA120, and DBA significantly inhibited the adhesion ofP. multocidato the ciliated epitheliumP<0.05and prevented the pathogen-induced increase in the number of GCsP<0.05compared with those of positive control tissues. In addition, VVA, SJA, UEA I, DSL, SBA, and ECL significantly inhibited the increase in GCs compared with that of the control tissues. The results suggest that less aggressive therapeutic strategies, such as treatment with lectins, may represent alternative approaches to control bacterial respiratory infections.

Planta Medica ◽  
2021 ◽  
Author(s):  
Birgit Waltenberger ◽  
Françoise Lohézic-Le Dévéhat ◽  
Thi Huyen Vu ◽  
Olivier Delalande ◽  
Claudia Lalli ◽  
...  

AbstractProtein tyrosine phosphatase 1B plays a significant role in type 2 diabetes mellitus and other diseases and is therefore considered a new drug target. Within this study, an acetone extract from the lichen Stereocaulon evolutum was identified to possess strong protein tyrosine phosphatase 1B inhibition in a cell-free assay (IC50 of 11.8 µg/mL). Fractionation of this bioactive extract led to the isolation of seven known molecules belonging to the depsidones and the related diphenylethers and one new natural product, i.e., 3-butyl-3,7-dihydroxy-5-methoxy-1(3H)-isobenzofurane. The isolated compounds were evaluated for their inhibition of protein tyrosine phosphatase 1B. Two depsidones, lobaric acid and norlobaric acid, and the diphenylether anhydrosakisacaulon A potently inhibited protein tyrosine phosphatase 1B with IC50 values of 12.9, 15.1, and 16.1 µM, respectively, which is in the range of the protein tyrosine phosphatase 1B inhibitory activity of the positive control ursolic acid (IC50 of 14.4 µM). Molecular simulations performed on the eight compounds showed that i) a contact between the molecule and the four main regions of the protein is required for inhibitory activity, ii) the relative rigidity of the depsidones lobaric acid and norlobaric acid and the reactivity related to hydrogen bond donors or acceptors, which interact with protein tyrosine phosphatase 1B key amino acids, are involved in the bioactivity on protein tyrosine phosphatase 1B, iii) the cycle opening observed for diphenylethers decreased the inhibition, except for anhydrosakisacaulon A where its double bond on C-8 offsets this loss of activity, iv) the function present at C-8 is a determinant for the inhibitory effect on protein tyrosine phosphatase 1B, and v) the more hydrogen bonds with Arg221 there are, the more anchorage is favored.


Endocrinology ◽  
2005 ◽  
Vol 146 (3) ◽  
pp. 1532-1540 ◽  
Author(s):  
Anne Florin ◽  
Magali Maire ◽  
Aline Bozec ◽  
Ali Hellani ◽  
Sonia Chater ◽  
...  

In the present study we investigated whether fetal exposure to flutamide affected messenger and protein levels of claudin-11, a key Sertoli cell factor in the establishment of the hemotesticular barrier, at the time of two key events of postnatal testis development: 1) before puberty (postnatal d 14) during the establishment of the hemotesticular barrier, and 2) at the adult age (postnatal d 90) at the time of full spermatogenesis. The data obtained show that claudin-11 expression was inhibited in prepubertal rat testes exposed in utero to 2 and 10 mg/kg·d flutamide. However, in adult testes, the inhibition was observed only with 2, and not with 10, mg/kg·d of the antiandrogen. It is shown here that these differences between prepubertal and adult testes could be related to dual and opposed regulation of claudin-11 expression resulting from positive control by androgens and an inhibitory effect of postmeiotic germ cells. Indeed, testosterone is shown to stimulate claudin-11 expression in cultured Sertoli cells in a dose- and time-dependent manner (maximum effect with 0.06 μm after 72 h of treatment). In contrast, postmeiotic germ cells potentially exert a negative effect on claudin-11 expression, because adult rat testes depleted in spermatids (after local irradiation) displayed increased claudin-11 expression, whereas in a model of cocultured Sertoli and germ cells, spermatids, but not spermatocytes, inhibited claudin-11 expression. The apparent absence of claudin-11 expression changes in adult rat testes exposed to 10 mg/kg·d flutamide therefore could result from the antagonistic effects of 1) the inhibitory action of the antiandrogen and 2) the stimulatory effect of the apoptotic germ cells on claudin-11 expression. Together, due to the key role of claudin-11 in the hemotesticular barrier, the present findings suggest that such regulatory mechanisms may potentially affect this barrier (re)modeling during spermatogenesis.


2013 ◽  
Vol 49 (4) ◽  
pp. 803-809
Author(s):  
Monica Lacerda Lopes Martins ◽  
Henrique Poltronieri Pacheco ◽  
Iara Giuberti Perini ◽  
Dominik Lenz ◽  
Tadeu Uggere de Andrade ◽  
...  

In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES), a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE) activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE) and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg), with acetylcholine (ACh) as positive control (5 µg/kg, i.v.). The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg) in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.). Captopril (30 mg/kg) was used as positive control. Bulbostylis capillaris (86.89 ± 15.20%) and ERE (74.89 ± 11.95%, ERE) were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%). ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.


Author(s):  
PAULA ALEJANDRA GIRALDO VILLAMIL ◽  
ANDRÉS CAMILO ANDRADE BURBANO ◽  
LUIS POMBO OSPINA ◽  
JANETH ARIAS PALACIOS ◽  
ÓSCAR EDUARDO RODRÍGUEZ AGUIRRE

Objective: The objective of the study was to determine the antimicrobial activity of leaf and flower extract in Chromolaena scabra (L. f.) R.M. King and H. Rob., against selected strains of bacteria and fungi. Methods: The agar diffusion method with plate perforation was developed; the microorganisms used were strains of Staphylococcus aureus and Escherichia coli, Aspergillus niger, and Penicillium digitatum. Rifampicin was used as a positive control. The evaluation was performed by measuring the diameter of the growth inhibition zones around the holes. The inhibitory effect of the plant extracts was obtained by its efficiency compared to the positive control. A comparison with fluconazole and ketoconazole was performed to determine how much of the extract is required to cause inhibition of fungal growth from the standard. Results: IC50 was determined by relating the ln of mass evaluated with respect to the square of the inhibition halo; ethanolic extracts of leaves and flowers of petroleum ether with IC50 values of 85.8 mg/ml and 50.3 mg/ml showed the highest inhibitory effect against S. aureus; the extract of petroleum ether and ethanol from leaves with IC50 of 64 mg/ml and 60 mg/ml, respectively. They were effective with A. niger. Leaf petroleum ether extract showed the best relative antifungal activity against A. niger with respect to fluconazole equivalent to 459.51 when fluconazole is 1.0. Conclusion: The extracts with high potential to inhibit the growth of microorganisms were determined to be ether flowers of petroleum and ethanol leaf extracts.


e-GIGI ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 238
Author(s):  
Stevia E. Nonutu ◽  
Damajanty H. C. Pangemanan ◽  
Christy N. Mintjelungan

Abstract: One of the treatment options of periodontal abscess caused by Fusobacterium nucleatum is administration of antibiotics. However, long-term antibiotics consumption can cause negative side effects. Therefore, alternative treatments that have low side effects and easy to be obtained are needed. Nike fish (Awaous melanocephalus) is one of the endemic fish of North Sulawesi province which has antibacterial properties. This study was aimed to evaluate the inhibition effect of nike fish extract on the growth of Fusobacterium nucleatum. This was a true experimental study with a posttest only control group design. We used modified Kirby-Bauer method with filter papers. Ciprofloxacin was used as the positive control and aquadest as the negative control. Extract of nike fish and stock of pure bacteria Fusobacterium nucleatum were prepared. The results showed that the average diameters of the inhibition zones formed in the nike fish extract after three repetitions, were as follows: for extract concentration of 12.5% was 2.91 mm; 25% was 4.16 mm; 50% was 8.41 mm; and 100% was 9.58 mm. In conclusion, nike fish extract (Awaous melanocephalus) at concentrations of 50% and 100% had a weak inhibitory effect (Himedia category) on the growth of Fusobacterium nucleatum meanwhile at concentrations of 12.5% and 25% there was no activity of zone of inhibition.Keywords: extract of nike fish (Awaous melanocephalus); Fusobacterium nucleatum; inhibitory effect Abstrak: Salah satu opsi pengobatan abses periodontal yang disebabkan oleh bakteri Fusobacterium nucleatum yaitu dengan penggunaan antibiotik namun mengonsumsi antibiotik jangka panjang dapat menimbulkan efek samping negatif. Oleh karena itu, diperlukan pengobatan alternatif yang memiliki efek samping rendah serta mudah didapat. Ikan nike merupakan salah satu ikan endemik Provinsi Sulawesi Utara yang berkhasiat sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui daya hambat ekstrak ikan nike (Awaous melanocephalus) terhadap pertumbuhan bakteri Fusobacterium nucleatum. Jenis penelitian ialah eksperimental murni dengan post test only control group design. Metode yang digunakan yaitu metode modifikasi Kirby-Bauer dengan menggunakan paper disk. Kontrol positif menggunakan antibakteri ciprofloxacin dan kontrol negatif menggunakan akuades. Pada penelitian ini digunakan ekstrak ikan nike dan stok bakteri murni Fusobacterium nucleatum. Hasil penelitian menunjukkan bahwa rerata diameter zona hambat yang terbentuk pada ekstrak ikan nike setelah tiga kali pengulangan yaitu untuk konsentrasi 12,5% sebesar 2,91 mm; 25% sebesar 4,16 mm; 50% sebesar 8,41 mm; dan 100% sebesar 9,58 mm. Simpulan penelitian ini ialah ekstrak ikan nike (Awaous melanocephalus) pada konsentrasi 50% dan 100% memiliki daya hambat kategori lemah (Himedia) terhadap pertumbuhan bakteri Fusobacterium nucleatum sedangkan pada konsentrasi 12,5% dan 25% dikategorikan tidak terdapat aktivitas zona hambat. Kata kunci: ekstrak ikan nike (Awaous melanocephalus); Fusobacterium nucleatum; daya hambat


2021 ◽  
Vol 13 (9) ◽  
pp. 1716-1723
Author(s):  
Jie Li ◽  
Chao Xu ◽  
Yueyue Lu ◽  
Yan Zhang ◽  
Xiaoping Tan

Nanoparticles are known to have recognition ability for targeted delivery, and are thus widely used in the treatments of diseases. Mesoporous nano-titanium dioxide (TiO2) nanoparticles have characteristics of nanomaterials and their porous structure with high surface area strengthens their drug-loading capacity and targeting ability. This study aimed to investigate the effect of mesoporous nano-TiO2 on pancreatic cancer cells and STAT pathway activity. Initially, we prepared mesoporous TiO2 nanoparticles that were characterized. Pancreatic cancer cells were co-cultured with mesoporous nano-TiO2 nanoparticles at different concentrations (0.1 μg/mL, 0.5 μg/mL, 1 μg/mL, 5 μg/mL, and 10 μg/mL) or 10 μg/mL nano-TiO2 (positive control group) or cells cultured alone (blank group). Cell viability was determined at several specific time points (24 h, 48 h, and 72 h). Transwell assay and scratching assay were conducted to determine the number of migrated and invaded cells. STAT3 and JAK2 expressions were examined by RT-qPCR and Western blot analysis. The prepared mesoporous nano-TiO2 exhibited sharp diffraction peaks with enhanced intensity and diffraction rings. STAT pathway was activated in pancreas cancer cells, which had more fluorescent cells than normal cells. The presence of mesoporous nano-TiO2 nanoparticles suppressed cancer cell viability and their inhibition rate increased with increased of nano-TiO2 concentration. The concentration of 10 μg/mL exhibited greatest inhibitory effect and 10 μg/mL mesoporous nano-TiO2 thus was chosen for experimental group. The width of the scratch in the experimental group (19.97±0.82 mm) was higher than in the blank group and positive control group (P < 0.05); 10 μg/mL mesoporous nano-TiO2 significantly decreased the number of invaded cells (71.97±17.84) and number of cell clones (156.91±31.03) (P < 0.05). The expression levels of STAT3 (0.41±0.06 μg/μL) and JAK2 (0.39±0.04 ug/ul) were diminished by treatment with mesoporous nano-TiO2. Mesoporous nano-TiO2 inhibits pancreatic cancer cell growth and STAT expression, as its inhibitory effect depends on its concentration. These findings might provide a novel insight into nanoparticle-based treatment for pancreatic cancer.


Author(s):  
NURINDAH SALOKA TRISNANINGRUM ◽  
HENDRI ASTUTY

Objective: This study aimed to ascertain the effectiveness of combination treatment with propolis and artemisinin-based combination therapy (ACT)in avoiding further resistance to ACT.Methods: A total of 35 mice were injected with Plasmodium berghei and divided into six equal groups: No treatment (negative control), ACT alone(positive control), 75-mg propolis/kg body weight (BW), 150-mg propolis/kg BW, ACT with 75-mg propolis/kg BW, and ACT with 150-mg propolis/kg BW. After 7 days of therapy, parasite density was calculated using a thin blood smear.Results: Parasite density significantly declined after combination treatment with ACT and 150-mg propolis/kg BW.Conclusion: Therapy with propolis alone showed no inhibitory effect on parasites, although its 150-mg/kg-BW dose was effective as an ACT adjuvantmalaria therapy in mice.


2012 ◽  
Vol 49 (No. 2) ◽  
pp. 35-41 ◽  
Author(s):  
I. Holko ◽  
J. Urbanova ◽  
THolkova ◽  
V. Kmet

The main goal of our work is the presentation and analysis of incidence of porcine respiratory disease complex (PRDC) regarding bacterial agents in the territory of northern districts of Slovakia. Mycoplasma hyopneumoniae and other secondary bacterial causative pathogens of PRDC comprised 75.2% of all cases (98) with clinical signs of respiratory infections that we examined in the course of one year. We present also one of possibilities to the solution of problematic detection of M. hyopneumoniae which is, like the whole rank of mycoplasmas, very difficult to cultivate. This problem was solved by using the PCR method with the direct isolation of M. hyopneumoniae from lungs tissue. In antibiotic sensitivity testing of Pasteurella multocida and Actinobacillus pleuropneumoniae resulted enrofloxacin as the most effective antibiotics in the therapy of PRDC regarding bacterial agents.in above mentioned territory.


Holzforschung ◽  
2019 ◽  
Vol 73 (7) ◽  
pp. 637-643 ◽  
Author(s):  
Yuya Kakumu ◽  
Kosei Yamauchi ◽  
Tohru Mitsunaga

Abstract Most of the wood bark produced by the forestry production is discarded in spite of containing many kinds of the phytochemical ingredients. The aim of the present study was to identify secondary metabolites from the bark of Larix kaempferi generated as waste material and evaluate their potential as cosmetic agents. Eighteen compounds, including a novel phenanthrene, 4,6,7-trihydroxyphenanthrene-2-O-β-D-glucopyranoside (16), were isolated from the bark of L. kaempferi and identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and nuclear magnetic resonance (NMR). In addition, the tyrosinase inhibitory activity of these compounds was evaluated. Procyanidin B7 (18) exhibited the most potent inhibition with IC50 values of 31.0 μM and 61.8 μM when using L-tyrosine and L-dopa as the substrate, respectively, which were similar to those of the positive control, kojic acid. Interestingly, quercetin-3-O-α-L-rhamnopyranoside (10) was shown to possess the tyrosinase inhibition although the other series of 3-glycoylated flavonols were not active, suggesting that the rhamnosyl group at C-3 and the hydroxyl group at C-3ʹ played an indispensable role in the anti-tyrosinase activity. These findings indicate that a number of constituents from L. kaempferi bark may have potential as additives in cosmetics.


2004 ◽  
Vol 11 (5) ◽  
pp. 825-834 ◽  
Author(s):  
Susan Sanchez ◽  
Shaikh Mizan ◽  
Charlotte Quist ◽  
Patricia Schroder ◽  
Michelle Juneau ◽  
...  

ABSTRACT Pasteurella multocida is a mucosal pathogen that colonizes the upper respiratory system of rabbits. Respiratory infections can result, but the bacteria can also invade the circulatory system, producing abscesses or septicemia. P. multocida produces extracellular sialidase activity, which is believed to augment colonization of the respiratory tract and the production of lesions in an active infection. Previously, it was demonstrated that some isolates of P. multocida contain two unique sialidase genes, nanH and nanB, that encode enzymes with different substrate specificities (S. Mizan, A. D. Henk, A. Stallings, M. Meier, J. J. Maurer, and M. D. Lee, J. Bacteriol. 182:6874-6883, 2000). We developed a recombinant antigen enzyme-linked immunosorbent assay (ELISA) based on the NanH sialidase of P. multocida and demonstrated that rabbits that were experimentally colonized with P. multocida produce detectable anti-NanH immunoglobulin M (IgM) and IgG in serum, although they demonstrated no clinical signs of pasteurellosis. In addition, clinically ill pet rabbits infected with P. multocida possessed IgM and/or IgG antibody against NanH. The NanH ELISA may be useful for the diagnosis of P. multocida infections in sick rabbits as well as for screening for carriers in research rabbit colonies.


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