The Effect of Antibiotics on Planktonic Cells and Biofilm Formation Ability of Collected Arcobacter-like Strains and Strains Isolated within the Czech Republic

The purpose of this study was to test the in vitro effects of ampicillin, ciprofloxacin, clindamycin, erythromycin, gentamicin, and tetracycline on planktonic cells of Arcobacter-like microorganisms and on their biofilm formation ability. The minimum inhibitory concentrations (MICs) were determined by the microdilution method. Further, biofilm formation ability in the presence of various concentrations of antibiotics was evaluated by a modified Christensen method. Most of the 60 strains exhibited high susceptibility to gentamicin (98.3%), ciprofloxacin (95.0%), and erythromycin (100.0%). High level of resistance was observed to clindamycin and tetracycline with MIC50 and MIC90 in range of 4–32 mg/L and 32–128 mg/L, respectively. Combined resistance to both clindamycin and tetracycline was found in 38.3% of tested strains. In general, higher biofilm formation was observed especially at lower concentrations of antibiotics (0.13–2 mg/L). However, a significant decrease in biofilm formation ability of Pseudarcobacter defluvii LMG 25694 was exhibited with ampicillin and clindamycin at concentrations above 32 or 8 mg/L, respectively. Biofilm formation represents a potential danger of infection and also a risk to human health, in particular due to antimicrobial-resistant strains and the ability to form a biofilm structure at a concentration that is approximately the MIC determined for planktonic cells.

Revisiting the Oxidation of Flavonoids: Loss, Conservation or Enhancement of Their Antioxidant Properties

Flavonoids display a broad range of health-promoting bioactivities. Among these, their capacity to act as antioxidants has remained most prominent. The canonical reactive oxygen species (ROS)-scavenging mode of the antioxidant action of flavonoids relies on the high susceptibility of their phenolic moieties to undergo oxidation. As a consequence, upon reaction with ROS, the antioxidant capacity of flavonoids is severely compromised. Other phenol-compromising reactions, such as those involved in the biotransformation of flavonoids, can also markedly affect their antioxidant properties. In recent years, however, increasing evidence has indicated that, at least for some flavonoids, the oxidation of such residues can in fact markedly enhance their original antioxidant properties. In such apparent paradoxical cases, the antioxidant activity arises from the pro-oxidant and/or electrophilic character of some of their oxidation-derived metabolites and is exerted by activating the Nrf2–Keap1 pathway, which upregulates the cell’s endogenous antioxidant capacity, and/or, by preventing the activation of the pro-oxidant and pro-inflammatory NF-κB pathway. This review focuses on the effects that the oxidative and/or non-oxidative modification of the phenolic groups of flavonoids may have on the ability of the resulting metabolites to promote direct and/or indirect antioxidant actions. Considering the case of a metabolite resulting from the oxidation of quercetin, we offer a comprehensive description of the evidence that increasingly supports the concept that, in the case of certain flavonoids, the oxidation of phenolics emerges as a mechanism that markedly amplifies their original antioxidant properties. An overlooked topic of great phytomedicine potential is thus unraveled.

Clinical Characteristics and Antimicrobial Susceptibility of Mycobacterium intracellulare and Mycobacterium abscessus Pulmonary Diseases: A Retrospective Study

The incidence of nontuberculous mycobacteria (NTM) diseases is increasing every year. The present study was performed to investigate the clinical characteristics, CT findings, and drug susceptibility test (DST) results of patients diagnosed with M. intracellulare or M. abscessus nontuberculous mycobacterial pulmonary disease (NTMPD). This retrospective study included patients diagnosed with NTMPD due to M. intracellulare or M. abscessus for the first time at Anhui Chest Hospital between 01/2019 and 12/2021. The patients were grouped as M. intracellulare-NTMPD group or M. abscessus-NTMPD group. Clinical features, imaging data and DST data, were collected. Patients with M. intracellulare infection had a higher rate of acid-fast smears (66.1% vs. 45.2%, P = 0.032 ) and a higher rate of cavitation based on pulmonary imaging (49.6% vs. 19.4%, P = 0.002 ) than patients with M. abscessus infection, but both groups had negative TB-RNA and GeneXpert results, with no other characteristics significant differences. The results of DST showed that M. intracellulare had high susceptibility rate to moxifloxacin (95.9%), amikacin (90.1%), clarithromycin (91.7%), and rifabutin (90.1%). M. abscessus had the highest susceptibility rate to amikacin (71.0%) and clarithromycin (71.0%). The clinical features of M. intracellulare pneumopathy and M. abscessus pneumopathy are highly similar. It may be easily misdiagnosed, and therefore, early strain identification is necessary. M. intracellulare has a high susceptibility rate to moxifloxacin, amikacin, clarithromycin, and rifabutin, while M. abscessus has the highest susceptibility rate to amikacin and clarithromycin. This study provides an important clinical basis for improving the management of NTMPD.

Landslide Susceptibility Mapping and Their Rainfall Thresholds Model in Tinalah Watershed, Kulon Progo District, Yogyakarta Special Region, Indonesia

Landslide often occurred in Tinalah watershed, Kulon Progo District, every year. The frequency of landslide events is increasing after high rainfall intensity. Some factors control landslides such as slope gradient, land use, geological structure, slope hydrology, and geological condition. This research has an objective to develop the susceptibility map of Tinalah watershed and to identify the rainfall threshold to trigger a landslide. The development of the susceptibility map using frequency ratio method with four parameters including slope, type of rock, land use, and lineament density. The landslide data were collected during the field survey and from regional disaster management authority (BPBD) Kulon Progo. Rainfall data were collected from BMKG and GSMap. Soil analysis also was conducted to develop a numerical model to verify the rainfall threshold value. The result shows a high susceptibility of the landslide area is dominated in Tinalah watershed. The rainfall threshold for the low susceptibility of the landslide zone is I=490.14 D-1.404with 5-7 days antecedent rain. The rainfall threshold for medium susceptibility map is I=164.32D-0,689 3-7 days antecedent rain. Moreover, the rainfall threshold for the high susceptibility of the landslide zone is 111.62 D-0.779, with 2-7 days antecedent rain.

Susceptibility of Plutella xylostella (L.) to Bacillus thuringiensis Berliner strains

The objective was to observe the susceptibility of a population of Plutella xylostella (L.) maintained for 100 generations in laboratory to strains of Bacillus thuringiensis Berliner. The concentrations 9×104, 1.5×105, 6×105, 8×105, 9×105, 1.5×106, 2×106, 3×106, 4.5×106, 6×106, 7.5×106, 9×106, 1.5×107, 2×107, 3×107, 4×107, 4.5×107, 6×107, 7.5×107, 9.5×107, 1.5×108 e 3×108 spores/mL were evaluated for the strains: E1, 49.30A, E2, 1.7L, T3A.259, T3A.140, T08024, E26, E22 and T07. The strains E26, E22 and T07 did not cause mortality for P. xylostella larvae. The P. xylostella larvae have a very high susceptibility pattern to the concentrations evaluated for six strains tested (E1, 49.30A, E2, 1.7L, T3A.259 and T3A.140). Only the T08.024 strain allowed the estimation of lethal concentration that kills 50% of the population (2.7 spores/mL).

Short-Term Waterlogging in Citrus Rootstocks

Changes in climate are provoking flooding events that cause waterlogging in the fields. Citrus are mainly cultivated in areas with a high susceptibility to climate change. Therefore, it is vital to explore their responses to these events to anticipate future challenges by means of genetic improvement of the commercial rootstocks. In this experiment, three popular commercial rootstocks, namely ‘Cleopatra’ (C. reshni Hort. Ex Tanaka), C. macrophylla, and ‘Forner Alcaide no. 5′ (Citrus reshni Hort. Ex Tanaka × Poncirus trifoliata), were evaluated after being submitted to short-term waterlogging and a period of recovery of 7 days in each case. Photosynthesis rate and stomatal conductance decreased in ‘Cleopatra’, while in the other two genotypes they were maintained (C. macrophylla) or restored after recovery (‘Forner Alcaide no. 5′). Relative water content and chlorophylls also decreased in ‘Cleopatra’. This indicates a deeper effect of flooding in ‘Cleopatra’, which suffered changes during flooding that were also sustained during the recovery phase. This did not occur in the other two rootstocks, since they showed signs of recovery for those parameters that decreased during waterlogging.

Recent advances in the enzymatic synthesis of lipophilic antioxidant and antimicrobial compounds

Due to the increase in the consumption of highly processed food in developed countries, as well as, a growing number of foodborne diseases, exploration of new food additives is an issue focusing on scientific attention and industrial interest. Functional compounds with lipophilic properties are remarkably desirable due to the high susceptibility to the deterioration of lipid-rich food products. This paper in a comprehensive manner provides the current knowledge about the enzymatic synthesis of lipophilic components that could act as multifunctional food additives. The main goal of enzymatic lipophilization of compounds intentionally added to food is to make these substances soluble in lipids and/or to obtain environmentally friendly surfactants. Moreover, lipase-catalyzed syntheses could result in changes in the antioxidant and antimicrobial activities of phenolic compounds, carbohydrates, amino acids (oligopeptides), and carboxylic acids. The review describes also the implementation of a new trend in green chemistry, where apart from simple and uncomplicated chemical compounds, the modifications of multi-compound mixtures, such as phenolic extracts or essential oils have been carried out.

Long-term assessment of risk factors for canine tumors registered in Xi’an, China

Tumors are one of the leading causes to death in pet dogs among diseases. The tumor incidence of pet dogs has been increasing, raising widespread concern.The tumor incidence of pet dogs has been increasing, raising widespread concern. In this study, retrospective analysis was performed with 246 tumor cases registered in Xi’an Animal Hospital, Northwest A&F University from 2009 to 2018. Correlations of sex, age and breed with tumor incidences were evaluated. The results showed that reproductive system tumors occupied the highest proportion (39.84%), followed by cutaneous tumors (28.05%), digestive tumors (18.70%) and ocular tumor (4.47%). Among the reproductive system tumors, breast tumors are the most common tumor in female pet dogs, especially for Pekingese (11.43%). Female dogs with high susceptibility to breast tumors were at the ages of 6–18 years old. As far as cutaneous tumors were concerned, the male pet dogs at all ages, particularly Golden Retrievers (17.39%), showed a high incidence. By contrast, male Samoyed aged from 4 to 13 years had the highest incidence (15.22%) of digestive tumors. In addition, pet dogs with ocular tumors mainly happened at the ages of 0–1 years and 6–13 years. Collectively, our findings are significant to develop effective measures of medical surveillance for pet dogs’ health and will provide insights for comparative oncology.

Virulence of Icelandic Pyrenophora teres f. teres populations and resistance of Icelandic spring barley lines

The causal agent of the barley net blotch disease, Pyrenophora teres, is known for its high level of diversity due to sexual reproduction. Different pathotypes, defined by a virulence combination, even within the same fields are frequently found and virulence between locations can vary considerably. Evaluation of virulence patterns of a pathogen population is essential for breeding resistant cultivars suitable for specific locations. To identify virulence patterns in Icelandic Pyrenophora teres f. teres (Ptt) isolates, twenty single spore isolates of Ptt were collected from seven locations in Iceland and analysed with AFLP markers. Principle Coordinate Analysis (PCoA) revealed Icelandic Ptt isolates clustering away from reference isolates from Austria, Finland, Sweden, Switzerland, UK, and USA. Hierarchical clustering grouped the Icelandic isolates into three distinct groups. Furthermore, the virulence of these twenty isolates was tested on 16 barley differential lines and revealed high variation in their virulence. Twenty-one barley cultivars commonly used in Iceland showed high susceptibility towards inoculation with Icelandic Ptt isolates.

COVID-19 Anosmia: High Prevalence, Plural Neuropathogenic Mechanisms, and Scarce Neurotropism of SARS-CoV-2?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative pathogen of coronavirus disease 2019 (COVID-19). It is known as a respiratory virus, but SARS-CoV-2 appears equally, or even more, infectious for the olfactory epithelium (OE) than for the respiratory epithelium in the nasal cavity. In light of the small area of the OE relative to the respiratory epithelium, the high prevalence of olfactory dysfunctions (ODs) in COVID-19 has been bewildering and has attracted much attention. This review aims to first examine the cytological and molecular biological characteristics of the OE, especially the microvillous apical surfaces of sustentacular cells and the abundant SARS-CoV-2 receptor molecules thereof, that may underlie the high susceptibility of this neuroepithelium to SARS-CoV-2 infection and damages. The possibility of SARS-CoV-2 neurotropism, or the lack of it, is then analyzed with regard to the expression of the receptor (angiotensin-converting enzyme 2) or priming protease (transmembrane serine protease 2), and cellular targets of infection. Neuropathology of COVID-19 in the OE, olfactory bulb, and other related neural structures are also reviewed. Toward the end, we present our perspectives regarding possible mechanisms of SARS-CoV-2 neuropathogenesis and ODs, in the absence of substantial viral infection of neurons. Plausible causes for persistent ODs in some COVID-19 convalescents are also examined.