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Topic Review
Human Milk Oligosaccharides
Human milk oligosaccharides (HMOs) are a family of free oligosaccharides which are diverse in structure and unique to human milk. Their diversity enables multiple paths of interference against viral entry, which include norovirus, rotavirus and human immunodeficiency virus (HIV). 
  • 941
  • 23 Apr 2021
Topic Review
Enteric Fever Diagnosis
Enteric fever, referring to typhoid fever and paratyphoid fever, is a common bacterial disease with high morbidity and mortality rates in low- to middle-income countries in Asia, Africa, and South America, associated with limited proper sanitation and safe drinking water supply.
  • 939
  • 05 May 2021
Topic Review
Bacterial Polyhydroalkanoate in a Sustainable Future
Environmental challenges related to the mismanagement of plastic waste became even more evident during the COVID-19 pandemic. The need for new solutions regarding the use of plastics came to the forefront again. Polyhydroxyalkanoates (PHA) have demonstrated their ability to replace conventional plastics, especially in packaging. Its biodegradability and biocompatibility makes this material a sustainable solution. The cost of PHA production and some weak physical properties compared to synthetic polymers remain as the main barriers to its implementation in the industry. The scientific community has been trying to solve these disadvantages associated with PHA.
  • 939
  • 20 Feb 2023
Topic Review
Antimicrobials and Food-Related Stresses
Ultraviolet (UV) radiation uses physical energy, and it is a non-thermal and non-chemical technology used by the food industry for liquid and solid surface decontamination, to control foodborne pathogens and spoilage microorganisms, as well as viruses and protozoa. UV radiations at short wavelengths, in the range of from 220 to 280 nm, result in physical damage to the nucleic acids and inhibit bacterial replication by induction of the formation of cyclobutene pyrimidine dimers, which blocks DNA replication and transcription, leading to cell death . However, the repair mechanism of UV damage, especially by photoreactivation, is a major disadvantage of UV disinfection .
  • 938
  • 10 Jun 2021
Topic Review
Biofilm in Endodontics
Sonic, ultrasonic and Er:Yag laser agitation, in general, offer better biofilm removal when compared to conventional irrigation methods delivered by syringe and needle. The choice of the right irrigation solution is an important factor for removal of the endodontic biofilm, with water and saline being less effective compared to NaOCl and CHX. However, due to heterogeneity in methodologies, it is difficult to compare adjuvant endodontic techniques with one another and give recommendations for the most efficient method in biofilm removal.
  • 938
  • 07 Apr 2022
Topic Review
Methicillin-Resistant Staphylococci in Animals and Food Products
Staphylococci are Gram-positive bacteria responsible for a wide variety of suppurative infections in humans and animals. Methicillin resistance acquisition is due to the integration of the staphylococcal cassette chromosome mec (SCCmec), which contains the mecA gene conferring β-lactam resistance. Methicillin-resistance in Staphylococci (MRS) pose a specific problem as they are in general more difficult to treat and may eventually result in death. Those MRS are now also increasingly found in different animal species and may compromise animal health as well as human health through the transmission of those MRS from animals to humans. As such it is important to know the situation of  MRS in animals and in foods.
  • 934
  • 07 Jul 2022
Topic Review
Rhizosphere Microbial Communities and Heavy-Metals
The rhizosphere is a microhabitat where there is an intense chemical dialogue between plants and microorganisms. The two coexist and develop synergistic actions, which can promote plants’ functions and productivity, but also their capacity to respond to stress conditions, including heavy metal (HM) contamination.
  • 933
  • 28 Jul 2021
Topic Review
CRC and Gut Microbiota
The gut microbiota plays an important role in maintaining homeostasis in the human body, and the disruption of these communities can lead to compromised host health and the onset of disease.
  • 931
  • 23 Jun 2021
Topic Review
Immune Response to Necrotic Enteritis in Broilers
Clostridium perfringens type A and C are the primary etiological agents associated with necrotic enteritis (NE) in poultry. The predisposing factors implicated in the incidence of NE changes the physical properties of the gut, immunological status of birds, and disrupt the gut microbial homeostasis, causing an over-proliferation of C. perfringens. The principal virulence factors contributing to the pathogenesis of NE are the α-toxin, β-toxin, and NetB toxin. The immune response to NE in poultry is mediated by the Th1 pathway or cytotoxic T-lymphocytes. C. perfringens type A and C are also pathogenic in humans, and hence are of public health significance. C. perfringens intoxications are the third most common bacterial foodborne disease after Salmonella and Campylobacter.
  • 928
  • 28 Oct 2022
Topic Review
Variants of SARS-CoV-2
The immune response elicited by the current COVID-19 vaccinations declines with time, especially among the immunocompromised population. Furthermore, the emergence of novel SARS-CoV-2 variants, particularly the Omicron variant, has raised serious concerns about the efficacy of currently available vaccines in protecting the most vulnerable people.
  • 928
  • 19 Apr 2023
Topic Review
Sources of Bioavailable Water in Desert Ecosystems
Water availability is the dominant driver of microbial community structure and function in desert soils. However, these habitats typically only receive very infrequent large-scale water inputs (e.g., from precipitation and/or run-off). In light of studies, the paradigm that desert soil microorganisms are largely dormant under xeric conditions is questionable. Gene expression profiling of microbial communities in desert soils suggests that many microbial taxa retain some metabolic functionality, even under severely xeric conditions.
  • 927
  • 24 Jul 2023
Topic Review
Metals and Metalloids by Actinobacteria
Actinobacteria include high GC bacteria that inhabit a wide range of terrestrial and aquatic ecological niches, where they play essential roles in recycling or transforming organic and inorganic substances. The metal(loid) tolerance and/or resistance of several members of this phylum rely on mechanisms such as biosorption and extracellular sequestration by siderophores and extracellular polymeric substances (EPS), bioaccumulation, biotransformation, and metal efflux processes, which overall contribute to maintaining metal homeostasis.
  • 926
  • 08 Jan 2021
Topic Review
Juglans regia L. Pellicle Extract
The difficulty to treat resistant strains-related hospital-acquired infections (HAIs) promoted the study of phytoextracts, known sources of bioactive molecules. Accordingly, in the present study, the pharmacological activities of Juglans regia (L.) pellicle extract (WPE) were investigated. The antiviral effect was tested against Herpes simplex virus type 1 and 2, Poliovirus 1, Adenovirus 2, Echovirus 9, Coxsackievirus B1 through the plaque reduction assay. The antibacterial and antifungal activities were evaluated against medically important strains, by the microdilution method.
  • 924
  • 23 Jun 2021
Topic Review
The Role of Metallophores in Staphylococcus aureus
Staphylococcus aureus (S. aureus) is considered one of the most widespread infectious bacteria. It is found in the environment as well as being part of the human skin and nasal microbiota. Normally, S. aureus is harmless on healthy skin, but once it enters the blood or internal tissues, diverse infections occur including pneumonia, infection of surgical site and nosocomial bacteremia. Systemic S. aureus infection depends on the bacteria breaking through the epithelial protective layer. The incidence rate of this serious medical condition is between 20 and 50 cases/100,000 per year, with fatality rate ranging from 10% to 30%. Moreover, S. aureus forms biofilms that are associated with medical device infections such as prosthetic joints and endocarditis. The prevalence of antibiotic resistance S. aureus isolates, methicillin-resistant S. aureus (MRSA), is posing a serious problem for combating infectious diseases caused by this pathogen.
  • 924
  • 28 Oct 2022
Topic Review
Bacteriophage Therapy to Control Bovine Mastitis
Bovine mastitis is a polymicrobial disease characterised by inflammation of the udders of dairy and beef cattle. The infection has huge implications to health and welfare of animals, impacting milk and beef production and costing up to EUR 32 billion annually to the dairy industry, globally. Bacterial communities associated with the disease include representative species from Staphylococcus, Streptococcus, Enterococcus, Actinomyces, Aerococcus, Escherichia, Klebsiella and Proteus. Conventional treatment relies on antibiotics, but antimicrobial resistance, declining antibiotic innovations and biofilm production negatively impact therapeutic efficacy. Bacteriophages (phages) are viruses which effectively target and lyse bacteria with extreme specificity and can be a valuable supplement or replacement to antibiotics for bovine mastitis. 
  • 924
  • 29 Aug 2023
Topic Review
Chaperone-Usher Fimbriae
Chaperone-usher fimbriae (CU) are linear, unbranching, outer-membrane pili secreted by Gram-negative bacteria through the chaperone-usher system rather than through type IV secretion or extracellular nucleation systems. These fimbriae are built up out of modular pilus subunits, which are transported into the periplasm in a Sec dependent manner. Chaperone-usher secreted fimbriae are important pathogenicity factors facilitating host colonisation, localisation and biofilm formation in clinically important species such as UPEC (uropathogenic Escherichia coli) and Pseudomonas aeruginosa.
  • 923
  • 15 Nov 2022
Topic Review
Antibiotic Bacterial Resistance
Antibiotics are the main treatment against bacterial infections in animals and plants. As explained before, efficacy loss is known as antibiotic resistance; this manifestation occurs when bacteria mutate in response to excess and sublethal doses of these drugs. Antibiotic resistance is usually classified into intrinsic and acquired resistance. The first one is constitutive of each species, which means that each generation will present it. In contrast, the acquired mechanism occurs when bacteria obtain resistance genes through conjugation, transformation, transduction, and transposition. Regardless of the type of resistance, both cause this problem.
  • 923
  • 18 Jan 2023
Topic Review
Microorganisms and Climate Change
Climate variations directly impacts on the primary productive sectors, such as agriculture, forestry, livestock, and commercial fishing, which present the subsequent economic relevance. As a result, the effect of climate change has been widely discussed for years on flora and fauna. However, the aftermath evaluation over the worldwide microbiota is a challenging task poorly considered, up to date. In fact, most of these effects have yet to be quantified, but the proliferation and geographycally spread of pathogens of plants, animals, or humans are providing clues of the possible results. These microbial issues should be kept in mind and are the core of this entry.
  • 923
  • 02 Jan 2024
Topic Review
Helminthophagous Fungi
Helminthophagous fungi can be divided into five groups: nematode-trapping/predatorial, opportunistic or ovicidal, endoparasitic, toxin-producing, and producers of special attack devices. The fungi of the first and second groups produce modified hyphae called traps, with which, by a mechanical/enzymatic process, they bind and digest nematode larvae, eggs, cysts, and nematode females. Thus, they are the ones that best act in the predation of animal parasites. Supplied orally, after passing through the gastrointestinal tract of animals, fungal structures such as conidia, mycelium, and chlamidospores germinate in the feces, forming a network of hyphae with the ability to capture and destroy infective forms of animal parasitic helminths.
  • 922
  • 30 Nov 2021
Topic Review
Bacterial Amelioration of Plant Drought and Salt Stress
Soil bacteria can express different plant-beneficial activities, inoculation of plants with one or more non-antagonistic microorganisms, belonging to the same or different species, or including both prokaryotic and eukaryotic organisms, can often facilitate plant growth. In fact, the lack of one plant beneficial activity in one strain can sometimes be overcome if another microorganism expresses this specific physiological trait. Moreover, the combination of diverse plant growth-promoting microorganisms (PGPM) offers a wide range of positive activity to a plant, including the enhancement of plant growth, reduced susceptibility to soil-borne diseases, increased yield, and improved seed and fruit nutritional value.
  • 921
  • 17 Mar 2022
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