Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Francisella tularensis in Ticks
Ticks can transmit a variety of infectious agents, including viruses, bacteria, and parasites, to humans and animals. Tularemia, caused by the Gram-negative bacterium Francisella tularensis, is a highly-infectious zoonotic agent that elicits flu-like symptoms in humans. In the United States, approximately half of tularemia cases are tick-associated. In a recent review by Tully and Huntley, the following points are highlighted: (1) Background information on tularemia and F. tularensis;  (2) What is known about the four different tick vectors associated with tularemia, including their geographic ranges and other arthropod vectors historically associated with tularemia;  (3) Physiological cues in ticks (compared to the mammalian host) that may prompt F. tularensis to modify its metabolism and protein expression to survive and persist in ticks.
  • 975
  • 15 Jan 2021
Topic Review
Liquid Fermentation of Edible and Medicinal Fungi
Liquid fermentation of edible and medicinal fungi involves cultivating and growing fungi in a liquid medium, providing optimal conditions for their growth and fermentation. This method offers advantages over traditional solid-state fermentation, such as better control of environmental factors, higher yield and purity, and faster production cycles. It also enables the extraction of bioactive compounds with therapeutic potential, which can be utilized in pharmaceuticals, nutraceuticals, cosmetics, and functional foods. Overall, it is a modern technique for producing high-quality fungal products with enhanced bioactive properties.
  • 975
  • 21 Sep 2023
Topic Review
Extensively Drug-resistant Tuberculosis
Extensively drug-resistant tuberculosis (XDR-TB) is a form of tuberculosis caused by bacteria that are resistant to some of the most effective anti-TB drugs. XDR-TB strains have arisen after the mismanagement of individuals with multidrug-resistant TB (MDR-TB). Almost one in four people in the world is infected with TB bacteria. Only when the bacteria become active do people become ill with TB. Bacteria become active as a result of anything that can reduce the person's immunity, such as HIV, advancing age, or some medical conditions. TB can usually be treated with a course of four standard, or first-line, anti-TB drugs (i.e., isoniazid, rifampin and any fluoroquinolone). If these drugs are misused or mismanaged, multidrug-resistant TB (MDR-TB) can develop. MDR-TB takes longer to treat with second-line drugs (i.e., amikacin, kanamycin, or capreomycin), which are more expensive and have more side-effects. XDR-TB can develop when these second-line drugs are also misused or mismanaged and become ineffective. The World Health Organization (WHO) defines XDR-TB as MDR-TB that is resistant to at least one fluoroquinolone and a second-line injectable drug (amikacin, capreomycin, or kanamycin). XDR-TB raises concerns of a future TB epidemic with restricted treatment options, and jeopardizes the major gains made in TB control and progress on reducing TB deaths among people living with HIV/AIDS. It is therefore vital that TB control be managed properly and new tools developed to prevent, treat and diagnose the disease. The true scale of XDR-TB is unknown as many countries lack the necessary equipment and capacity to accurately diagnose it. By June 2008, 49 countries had confirmed cases of XDR-TB. By the end of 2017, 127 WHO Member States reported a total of 10,800 cases of XDR-TB, and 8.5% of cases of MDR-TB in 2017 were estimated to have been XDR-TB. In August 2019, the Food and Drug Administration (FDA) approved the use of Pretomanid in combination with bedaquiline and linezolid for treating a limited and specific population of adult patients with extensively drug resistant, treatment-intolerant or nonresponsive multidrug resistant pulmonary TB.
  • 972
  • 24 Oct 2022
Topic Review
Antimicrobial Resistance in Acinetobacter baumannii
Acinetobacter baumannii is a Gram-negative bacillus that causes multiple infections that can become severe, mainly in hospitalized patients. Its high ability to persist on abiotic surfaces and to resist stressors, together with its high genomic plasticity, make it a remarkable pathogen. The isolation of strains with high antimicrobial resistance profiles has gained relevance, which complicates patient treatment and prognosis. This resistance capacity is generated by various mechanisms, including the modification of the target site where antimicrobial action is directed. This mechanism is mainly generated by genetic mutations and contributes to resistance against a wide variety of antimicrobials, such as β-lactams, macrolides, fluoroquinolones, aminoglycosides, among others, including polymyxin resistance, which includes colistin, a rescue antimicrobial used in the treatment of multidrug-resistant strains of A. baumannii and other Gram-negative bacteria.
  • 971
  • 27 Jun 2022
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.
  • 971
  • 05 May 2021
Topic Review
Glacial Water
Microbial communities and nutrient dynamics in glaciers and ice sheets continuously change as the hydrological conditions within and on the ice change. Glaciers and ice sheets can be considered bioreactors as microbiomes transform nutrients that enter these icy systems and alter the meltwater chemistry. Global warming is increasing meltwater discharge, affecting nutrient and cell export, and altering proglacial systems.
  • 970
  • 15 May 2023
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.
  • 969
  • 07 Apr 2022
Topic Review
SARS-related Coronavirus
Severe acute respiratory syndrome–related coronavirus (SARS-CoV or SARSr-CoV)[note 1] is a species of coronavirus that infects humans, bats and certain other mammals. It is an enveloped positive-sense single-stranded RNA virus that enters its host cell by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. It is a member of the genus Betacoronavirus and subgenus Sarbecovirus. Two strains of the virus have caused outbreaks of severe respiratory diseases in humans: severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1), which caused the 2002–2004 outbreak of severe acute respiratory syndrome (SARS), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is causing the 2019–20 pandemic of coronavirus disease 2019 (COVID-19). There are hundreds of other strains of SARS-CoV, all of which are only known to infect non-human species: bats are a major reservoir of many strains of SARS-related coronaviruses, and several strains have been identified in palm civets, which were likely ancestors of SARS-CoV. The SARS-related coronavirus was one of several viruses identified by the World Health Organization (WHO) in 2016 as a likely cause of a future epidemic in a new plan developed after the Ebola epidemic for urgent research and development before and during an epidemic towards diagnostic tests, vaccines and medicines. The prediction came to pass with the COVID-19 pandemic.
  • 969
  • 29 Sep 2022
Topic Review
Meningococcal Vaccines and Mucosal Immunity
Neisseria meningitidis causes a devastating invasive disease but is also a normal colonizer of the human nasopharynx. Due to the rapid progression of disease, the best tool to protect individuals against meningococcal infections is immunization. Clinical experience with polysaccharide conjugate vaccines has revealed that an ideal meningococcal vaccine must prevent both invasive disease and nasal colonization, which confers herd immunity. However, not all meningococcal vaccines are equal in their ability to prevent nasal colonization, for unknown reasons. 
  • 969
  • 23 Jul 2021
Topic Review
Mycobacterium tuberculosis and HIV-1: Evolution
This entry reviews the genetic evolution and adaptation to the host environment of M. tuberculosis and HIV-1. It provides an overview of the latest developments in the knowledge about the genetic diversity of these devastating intracellular human pathogens and its impact on the host immune system, virulence, drug resistance propensity and other relevant aspects. We also proposed a novel topic in the literature regarding the use of single cell "omics" to study the interacting evolutionary dynamics of M. tuberculosis and HIV-1 in co-infection, at the cellular niche of monocytes/macrophages.
  • 968
  • 20 Jan 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.
  • 968
  • 28 Oct 2022
Topic Review
Bioresources Use in Organic Farming
Over the years, the practice of agriculture has transformed from the era of traditional to that of intensive agriculture in the bid to boost the production index that will satisfy the food needs of the globally growing population. However, the continuous and exaggerated use of chemical fertilizers and pesticides has resulted in major adverse impacts on food and environmental safety, whereas most traditional techniques for the reclamation of natural soil nutrients, including shifting cultivation and polyculture, are no longer attractive measures of land rejuvenation. There is, therefore, the need for urgent evaluation and adoption of innovative methods of replenishing the agricultural soils that conform to the current agricultural systems without exerting undesirable effects on the ecosystem. We elucidated the use of key bioresources, such as organic fertilizers, biofertilizers, and biopesticides, as alternatives to chemical-based products in attaining a safe and sustainable agricultural system. Bioresources are naturally available, safe, and easily accessible products. The potential of these biological products in fostering soil microbial growth, plants’ productivity, and induced host immunity to diseases, alongside the promotion of healthy soil–microbe–plant relationships and preservation of the ecosystem processes without disruption, are aspects that were also explored. Therefore, the productive use of bioresources is considered strategic as it pertains to attaining safe and sustainable food production. 
  • 966
  • 02 Jun 2023
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.
  • 965
  • 30 Nov 2021
Topic Review
Equine Herpesvirus 1
Equine herpesvirus 1 (EHV-1) is a virus of the family Herpesviridae that causes abortion, respiratory disease and occasionally neonatal mortality in horses. Initial spread of EHV-1 by a newly introduced horse through direct and indirect contact can lead to abortion and perinatal infection in up to 70 percent of a previously unexposed herd. Abortion usually occurs in the last four months of gestation, two to four weeks after infection of the mare. Perinatal (around the time of birth) infection can lead to pneumonia and death. Encephalitis can occur in affected animals, leading to ataxia, paralysis, and death. There is a vaccine available (ATCvet code QI05AA11 (WHO)), however its efficacy is questionable.The virus varies in severity from sub-clinical to very severe. Most horses have been infected with EHV-1 but the virus can become latent and show no signs and never be an issue. In 2006, an outbreak of EHV-1 among stables in Florida resulted in the institution of various quarantine measures. The outbreak was determined to have originated with several horses imported from Europe via New York, and then shipped to Florida.
  • 963
  • 04 Nov 2022
Topic Review
Gut Microbiota in Anabolic Resistance
The gut microbiota refers to the collective of bacteria, archaea, viruses, and eukaryotic microbes that reside in the gastrointestinal tract.
  • 960
  • 10 Mar 2021
Topic Review
Viable but Non-Culturable Listeria monocytogenes
The detection, enumeration, and virulence potential of viable but non-culturable (VBNC) pathogens continues to be a topic of discussion. While there is a lack of definitive evidence that VBNC Listeria monocytogenes (Lm) pose a public health risk, recent studies suggest that Lm in its VBNC state remains virulent. VBNC bacteria cannot be enumerated by traditional plating methods, so the results from routine Lm testing may not demonstrate a sample’s true hazard to public health. We suggest that supplementing routine Lm testing methods with methods designed to enumerate VBNC cells may more accurately represent the true level of risk.
  • 959
  • 13 Feb 2021
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). 
  • 959
  • 23 Apr 2021
Topic Review
Mycobacteria and Cancer
Although the therapeutic effect of mycobacteria as antitumor agents has been known for decades, recent epidemiological and experimental studies have revealed that mycobacterium-related chronic inflammation may be a possible mechanism of cancer pathogenesis. Mycobacterium tuberculosis and non-tuberculous Mycobacterium avium complex infections have been implicated as potentially contributing to the etiology of lung cancer, whereas Mycobacterium ulcerans has been correlated with skin carcinogenesis. The risk of tumor development with chronic mycobacterial infections is thought to be a result of many host effector mechanisms acting at different stages of oncogenesis.
  • 959
  • 28 Sep 2021
Topic Review
Water Age and Plumbing Pathogens
One of the most important characteristics that can affect the growth and proliferation of opportunistic pathogens in premise plumbing systems is water age. Water age is a term that represents the average time taken for water to reach its point-of-use from its point-of-entry within a distribution system. It is more precisely defined as a summation of residence time from the treatment facility to the water meter of a building (i.e., mains distribution) and residence time from the water meter to the point of use (i.e., premise plumbing distribution). Water age can be described primarily as a function of water demand, system design, and system operation. As demand increases, the time that water is resident in a system decreases.
  • 956
  • 08 Jun 2021
Topic Review
A Mycobacteriophage-Based Vaccine Platform for SARS-CoV-2
Bacteriophage-based vaccines can generate a protective immune response by safely introducing foreign antigens displayed on, encapsidated within, or genetically encoded by phage. Here authors describe recombinants of mycobacteriophage Bxb1 (a phage infecting Mycobacterium smegmatis) that covalently display and express antigenic peptides of the SARS-CoV-2 Spike protein. Several of these vaccine candidates produced Spike-specific antibodies in immunized mice, but the responses were not neutralizing. This mycobacteriophage-based vaccine platform can likely be improved if delivery of larger antigens is achieved. 
  • 956
  • 06 Dec 2021
  • Page
  • of
  • 52
Featured Entry Collections
>>

Featured Reprints

>>
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Medieval Royal Iconography
Academic Video Service
Feedback