The aim of this study was to evaluate the antibacterial activity of coriander essential oil and its major constituent, linalool, in combination with antibiotics against Gram‐positive (methicillin‐susceptible and methicillin‐resistant Staphylococcus aureus, S. epidermidis) and Gram‐negative bacteria (Pseudomonas aeruginosa, Escherichia coli). The chemical composition of coriander essential oil was analyzed by gas chromatography with flame ionization and mass spectrometry detection. The antibacterial activity of coriander essential oil, linalool and their combinations with antibiotics were assessed by the broth microdilution and checkerboard assays respectively. Thirty‐four compounds were identified in coriander essential oil, linalool (70·11%) being predominant. Coriander essential oil and linalool showed synergistic interactions with antibiotics (oxacillin, amoxicillin, gentamicin, ciprofloxacin, tetracycline) against both Gram‐positive and Gram‐negative bacteria. In these synergistic combinations, minimum inhibitory concentrations of antibiotics were markedly reduced; even antibiotic resistance reversal activity was recorded. These findings are very promising for the development of new therapeutic options for bacterial infections. Significance and Impact of the Study Methicillin‐resistant Staphylococcus aureus (MRSA) and Gram‐negative bacteria are still major threats to human health and, therefore, identification of new antibacterial agents or combinations with high potency is needed. Our study found synergistic interactions between coriander essential oil/linalool and antibiotics against MRSA and other Gram‐positive bacteria (methicillin‐susceptible S. aureus, S. epidermidis), but also Gram‐negative bacteria (Pseudomonas aeruginosa, Escherichia coli). Increase in antibiotic susceptibility and reversal of antibiotic resistance were also demonstrated. Combinations of coriander essential oil/linalool and antibiotics are thus very promising for the development of novel antibacterials.

Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications.

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Combination of antibiotics with natural products is a promising strategy for potentiating antibiotic activity and overcoming antibiotic resistance. The purpose of the present study was to investigate whether morusin and kuwanon G, prenylated phenolics in Morus species, have the ability to enhance antibiotic activity and reverse antibiotic resistance in Staphylococcus aureus and Staphylococcus epidermidis . Commonly used antibiotics (oxacillin, erythromycin, gentamicin, ciprofloxacin, tetracycline, clindamycin) were selected for the combination studies. Checkerboard and time-kill assays were used to investigate potential bacteriostatic and bactericidal synergistic interactions, respectively between morusin or kuwanon G and antibiotics. According to both fractional inhibitory concentration index and response surface models, twenty combinations (14 morusin-antibiotic combinations, six kuwanon G-antibiotic combinations) displaying bacteriostatic synergy were identified, with 4–512-fold reduction in the minimum inhibitory concentration values of antibiotics in combination. Both morusin and kuwanon G reversed oxacillin resistance of methicillin-resistant Staphylococcus aureus. In addition, morusin reversed tetracycline resistance of Staphylococcus epidermidis . At half of the minimum inhibitory concentrations, combinations of morusin with oxacillin or gentamicin showed bactericidal synergy against methicillin-resistant Staphylococcus aureus. Fluorescence and differential interference contrast microscopy and scanning electron microscopy showed an increase in the membrane permeability and massive leakage of cellular content in methicillin-resistant Staphylococcus aureus exposed to morusin or kuwanon G . Overall, our findings strongly indicate that both prenylated compounds are good candidates for the development of novel antibacterial combination therapies.

Feline and canine coronaviruses (FCoV and CCoV, respectively) are common pathogens of cats and dogs sometimes leading to lethal infections named feline infectious peritonitis (FIP) and canine pantropic coronavirus infection. FCoV and CCoV are each subdivided into two serotypes, FCoV-I/II and CCoV-I/II. A phylogenetic relationship is evident between, on one hand, CCoV-I/FCoV-I, and on the other hand, CCoV-II/FCoV-II, suggesting that interspecies transmission can occur. The aim of the present study was to evaluate the prevalence of coronavirus (CoV)-infected cats according to their contact with dogs and to genetically analyse the CoV strains infecting cats. From 2003 to 2009, we collected 88 faecal samples from healthy cats and 11 ascitic fluids from FIP cats. We investigated the possible contact with dog in the household and collected dogs samples if appropriate. Out of 99 cat samples, 26 were coronavirus positive, with six cats living with at least one dog, thus showing that contact with dogs does not appear as a predisposing factor for cats CoV infections. Molecular and phylogenetic analyses of FCoV strains were conducted using partial N and S sequences. Six divergent strains were identified with the N gene clustering with CCoV-I whereas the 3' end of S was related to FCoV-I. Further analysis on those six samples was attempted by researching the presence of the ORF3 gene, the latter being peculiar to CCoV-I to date. We succeeded to amplify the ORF3 gene in five samples out of six. Thus, our data strongly suggest the circulation of atypical FCoV strains harbouring the CCoV-I ORF3 gene among cats. Moreover, the ORF3 genes recovered from the feline strains exhibited shared deletions, never described before, suggesting that these deletions could be critical in the adaptation of these strains to the feline host.

The neurohormone oxytocin is known to exert a special function in the regulation of social relationships throughout vertebrate taxa. Recently it has been discovered that not only within-species, but in certain cases, between-species social bonds are also mediated by the same hormone, e.g. in case of the dog�human relationship. However, despite the exponential growth of findings at the behavioural level, there are still a lot of controversies on the biochemical assessment of oxytocin in canine samples. Thus, in the current study we replicate previous findings of canine serum oxytocin increase following a positive dog�human interaction. We provide a detailed description of both the immunoassay method used as well as the behavioural protocol (including crucial time-parameters). This will serve as a base for further studies that both our group as well as others in the field will conduct.

Lately there are increased evidences that oxytocin may be an important mediator in several psychiatric disorders including depression and anxiety. Oxytocin system seems to be linked with several neurotransmitters important in psychiatric disorder, but also with the hypothalamic�pituitary�adrenal (HPA) axis and is also a key factor in stress regulation mechanisms. Considering the oxytocin receptor pattern of distribution both central and peripherally and the growing data concerning the disbalance of oxytocin in psychiatric disorders we may speculate that oxytocin system may be at the core of psychosomatic disturbances. Also, recent data brought to attention that oxytocin receptor is distributed throughout gastrointestinal tract. Our hypothesis of the present study was that oxytocin system is disbalanced in irritable bowel syndrome considering also the psychological component of this digestive disorder. We preliminary report here a significant decrease of serum oxytocin levels in patients with major depression disorder and irritable bowel syndrome, as compared with those with major depression disorder alone.

Caprine arthritis encephalitis is an important disease of dairy goats with a worldwide distribution. Despite the eradication programs, this disease is still prevalent and causing huge financial losses due to reduced lactation performance and culling. The aim of this study was to reveal the presence of CAEV antibodies among a goat population from the North-Eastern of Romania. During 2014-2016, a total of 295 blood samples were collected from healthy or diseased animals. The serum samples were tested for CAEV antibodies detection, using the agar gel immunodiffusion (AGID) test. Within the 295 serum samples tested by AGID technique, 31.86% were confirmed as being positive. All positive samples came from subjects without clinical signs of disease. The results obtained in this preliminary study; show that CAEV is present in French Alpine goats breed within a farm in North-Eastern of Romania.