Antibiofilm action using water-soluble tetra-cationic porphyrin and antibacterial photodynamic therapy against Moraxella spp. from cattle.

Infectious bovine keratoconjunctivitis (IBK) is the most important eye disease in ruminants worldwide. Moraxella bovis and Moraxella bovoculi can form biofilm and are frequently isolated from affected animals. Antimicrobials are used worldwide to treat clinical cases of IBK, although they have limited success in clearing the infection. Therefore, photodynamic therapy using porphyrins as photosensitizing molecules is an alternative method to eliminate microorganisms, including biofilms. We evaluated the antibacterial activity of a zinc(II) metalloporphyrin (ZnTMeP) against M. bovis and M. bovoculi biofilms since this compound can efficiently inactivate planktonic Moraxella spp. This study was carried out with two reference strains of Moraxella spp. (M. bovis: ATCC® 10900 and M. bovoculli: ATCC® BAA1259). The antibacterial activity of 4.0 µM of the ZnTMeP porphyrin was evaluated on forming and consolidate biofilms with three 30-min cycles of white-light exposure for three days. The ZnTMeP porphyrin reduced M. bovis and M. bovoculi biofilm formation. In addition, ZnTMeP partially destroyed consolidated M. bovoculi biofilms in the second white-light irradiation cycle, although the porphyrin had no effect against the consolidated biofilm of M. bovis. Despite the biofilm still not being completely inactivated, our findings are promising and encourage further experiments using the phototherapy protocol.

MALDI-TOF MS Biomarker Detection Models to Distinguish RTX Toxin Phenotypes of Moraxella bovoculi Strains Are Enhanced Using Calcium Chloride Supplemented Agar.

Moraxella bovoculi is the bacterium most often cultured from ocular lesions of cattle with infectious bovine keratoconjunctivitis, also known as bovine pinkeye. Some strains of M. bovoculi contain operons encoding for a repeats-in-toxin (RTX) toxin, which is a known virulence factor of multiple veterinary pathogens. We explored the utility of MALDI-TOF MS and biomarker detection models to classify the presence or absence of an RTX phenotype in M. bovoculi. Ninety strains that had undergone whole genome sequencing were classified by the presence or absence of complete RTX operons and confirmed with a visual assessment of hemolysis on blood agar. Strains were grown on Tryptic Soy Agar (TSA) with 5% sheep blood, TSA with 5% bovine blood that was supplemented with 10% fetal bovine serum, 10 mmol/LCaCl2, or both. The formulations were designed to determine the influence of growth media on toxin production or activity, as calcium ions are required for toxin secretion and activity. Mass spectra were obtained for strains grown on each agar formulation and biomarker models were developed using ClinProTools 3.0 software. The most accurate model was developed using spectra from strains grown on TSA with 5% bovine blood and supplemented with CaCl2, which had a sensitivity and specificity of 93.3% and 73.3%, respectively, regarding RTX phenotype classification. The same biomarker model algorithm developed from strains grown on TSA with 5% sheep blood had a substantially lower sensitivity and specificity of 68.0% and 52.0%, respectively. Our results indicate that MALDI-TOF MS biomarker models can accurately classify strains of M. bovoculi regarding the presence or absence of RTX toxin operons and that agar media modifications improve the accuracy of these models.

Queratoconjuntivitis asociada a dermatitis atópica tratada con tocilizumab / Keratoconjunctivitis associated with atopic dermatitis treated with tocilizumab

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Effects of Ocimum gratissimum L essential oil at subinhibitory concentrations on virulent and multidrug-resistant Shigella strains from Lagos, Nigeria.

Ocimum gratissimum leaf extracts have been extensively demonstrated to be effective against the various aetiologic agents of diarrhoea, including Shigellae. However, the mechanism of the shigellocidal action of this plant remains to be understood. This study investigated the effects of O. gratissimum essential oil (EO) at subinhibitory concentrations of 0.75 and 1.0 microg/ml on virulence and multidrug-resistant strains of 22 Shigella isolates from Nigeria. Compared with untreated Shigella strains, O. gratissimum EO caused significant decreases (p<0.01) in extracellular protease activity, o-lipopolysaccharide rhamnose content and incidence of invasiveness mediated as keratoconjunctivitis in guinea pig. The disparity in extracellular protease activity and o-lipopolysacharide rhamnose between the two treatment groups was also found to be significant (p<0.05), suggesting greater anti-virulent effects of O. gratissimum oil at 1.0 microg/ml. Antibiotic susceptibility testing revealed that the EO of O. gratissimum reduced the MICs of antibiotics to which Shigellae showed resistance by 9.8-53.1% and fluoroquinolones by 18.2-45.5%. The results of this study strongly suggest inhibition of extracellular protease and expression of O-LPS rhamnose in Shigellae by O. gratissimum EO. The future use of O. gratissimum- antibiotic combinations as a therapeutic measure against shigellosis is discussed.

Tratamiento de la blefaroconjuntivitis y queratoconjuntivitis con ciprofloxacina al 0.3 por ciento vs tobramicina al 0.3 por ciento en solucion oftálmica / Treatment of blepharoconjunctivitis and keratoconjunctivitis with ciprofloxinine 0.3 por ciento vs tobramicine 0.3 por ciento in ophtalmic solution

Se diseño un estudio doble ciego, prospectivo, longitudinal y experimental comparando la eficacia, tolerancia y toxicidad de la criprofloxacina y la tobramicina tópica al 0.3 por ciento en el tratamiento de las blefaroconjuntivitis y las queratoconjuntivitis. Se incluyeron 40 ojos en cada grupo, encontrando que ambos fármacos son igualmente efectivos para erradicar o reducir los gérmenes causantes de infección en un 95 por ciento. La ciprofloxacina dismuyó el lagrimeo y prurito en forma estadísticamente más importante (p<0.05) que la tombracina además de ser mejor tolerada y no haber provocado efectos tóxicos secundarios

Topical fumagillin in the treatment of microsporidial keratoconjunctivitis in AIDS.

OBJECTIVE: To report microsporidial keratoconjunctivitis in a patient infected with HIV who was treated with topical fumagillin. CASE SUMMARY: A 37-year-old white man who was experiencing redness, pain, irritation, decreased vision, and a foreign body sensation occurring in both eyes was referred to the ophthalmology clinic. The patient had a medical history significant for AIDS, Pneumocystis carinii pneumonia, and Cytomegalovirus retinitis. Conjunctival smears were taken and stained positive for the presence of Microsporidia. The patient was diagnosed with bilateral microsporidial keratoconjunctivitis and fumagillin therapy was initiated. After 5 days of therapy, the patient reported significant improvements characterized by a decrease in blurred vision with only slight blurring in the left eye, decrease in headache, and decreased foreign body sensation. The patient continued topical fumagillin therapy for more than 14 months, with only slight blurring in the left eye and no apparent ocular toxicity as a result of fumagillin therapy. DISCUSSION: Although rare in occurrence, increasing numbers of documented microsporidial infections are being reported in the medical literature, particularly in individuals who are seropositive for HIV. Clinicians need to be cognizant of microsporidial keratoconjunctivitis as another opportunistic infection in this patient population. CONCLUSIONS: Although a curative agent has yet to be discovered, fumagillin represents a safe, effective, low-cost, topical agent for the treatment of microsporidial keratoconjunctivitis.

Estimation of fimbrial vaccine effectiveness in protection against keratoconjunctivitis infectiosa in calves considering different routes of introducing vaccine antigene.

Infectious Bovine Keratoconjunctivitis (IBK) is one of diseases of a very complex etiology constituting a serious epizootiologic and economic problem in cattle raising on a large scale. The primary and most pathogenic etiological factor is Gram negative Moraxella bovis bacteria. The present work was undertaken to compare the efficiency of different systems of vaccination and determine their influence on forming the profile of different types of immunity.