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Current Medicinal Chemistry 2020Endophytes represent a complex community of microorganisms colonizing asymptomatically internal tissues of higher plants. Several reports have shown that endophytes... (Review)
Review
BACKGROUND
Endophytes represent a complex community of microorganisms colonizing asymptomatically internal tissues of higher plants. Several reports have shown that endophytes enhance the fitness of their host plants by direct production of bioactive secondary metabolites, which are involved in protecting the host against herbivores and pathogenic microbes. In addition, it is increasingly apparent that endophytes are able to biosynthesize medicinally important "phytochemicals", originally believed to be produced only by their host plants.
OBJECTIVE
The present review provides an overview of secondary metabolites from endophytic fungi with pronounced biological activities covering the literature between 2010 and 2017. Special focus is given on studies aiming at exploration of the mode of action of these metabolites towards the discovery of leads from endophytic fungi. Moreover, this review critically evaluates the potential of endophytic fungi as alternative sources of bioactive "plant metabolites".
RESULTS
Over the past few years, several promising lead structures from endophytic fungi have been described in the literature. In this review, 65 metabolites are outlined with pronounced biological activities, primarily as antimicrobial and cytotoxic agents. Some of these metabolites have shown to be highly selective or to possess novel mechanisms of action, which hold great promises as potential drug candidates.
CONCLUSION
Endophytes represent an inexhaustible reservoir of pharmacologically important compounds. Moreover, endophytic fungi could be exploited for the sustainable production of bioactive "plant metabolites" in the future. Towards this aim, further insights into the dynamic endophyte - host plant interactions and origin of endophytic fungal genes would be of utmost importance.
Topics: Anti-Infective Agents; Endophytes; Fungi; Phytochemicals; Plants
PubMed: 31526342
DOI: 10.2174/0929867326666190916144709 -
Microbiology Spectrum Mar 2019is usually regarded as a bacterial pathogen due to its ability to cause multiple types of invasive infections. Nevertheless, colonizes about 30% of the human... (Review)
Review
is usually regarded as a bacterial pathogen due to its ability to cause multiple types of invasive infections. Nevertheless, colonizes about 30% of the human population asymptomatically in the nares, either transiently or persistently, and can therefore be regarded a human commensal as well, although carriage increases the risk of infection. Whereas many facets of the infection processes have been studied intensively, little is known about the commensal lifestyle of . Recent studies highlight the major role of the composition of the highly variable nasal microbiota in promoting or inhibiting colonization. Competition for limited nutrients, trace elements, and epithelial attachment sites, different susceptibilities to host defense molecules and the production of antimicrobial molecules by bacterial competitors may determine whether nasal bacteria outcompete each other. This chapter summarizes our knowledge about mechanisms that are used by for efficient nasal colonization and strategies used by other nasal bacteria to interfere with its colonization. An improved understanding of naturally evolved mechanisms might enable us to develop new strategies for pathogen eradication.
Topics: Bacteria; Bacterial Physiological Phenomena; Humans; Microbiota; Nasal Cavity; Staphylococcal Infections; Staphylococcus aureus
PubMed: 31004422
DOI: 10.1128/microbiolspec.GPP3-0029-2018 -
Anti-inflammatory & Anti-allergy Agents... 2023Cryptococcus neoformans and C. gattii pneumonitis could persist asymptomatically for indefinite periods, resolve, or progress to symptomatic dissemination, mainly in...
Cryptococcus neoformans and C. gattii pneumonitis could persist asymptomatically for indefinite periods, resolve, or progress to symptomatic dissemination, mainly in immunocompromised individuals (e.g., treated with corticosteroids). The symptoms of COVID-19 may range from a self-limiting illness with general symptoms, such as fever, to more severe complications, such as pneumonitis. The glucocorticoids emerged as potential for treatment of COVID-19, mainly those patients who required ventilator therapy. However, although treatment with glucocorticoids has shown benefits in patients with COVID-19, they can be dangerous due to increased risk of coinfections and superinfections caused by opportunistic pathogens such as Cryptococcus ssp. Some patients with severe COVID-19 pneumonia treated with glucocorticoids developed cryptococcal infection and died. Therefore, immunomodulatory therapy could increase the susceptibility to acute infection or reactivation of Cryptococcus ssp in COVID-19 patients, and this could be complicated once pulmonary cryptococcosis has symptoms similar to COVID-19 becomes difficult to distinguish between the two disease states and treatment.
Topics: Humans; Glucocorticoids; COVID-19; Cryptococcosis; Cryptococcus neoformans; Cryptococcus gattii
PubMed: 37702231
DOI: 10.2174/1871523022666230912142540 -
Dermatologic Clinics Oct 2021Children are a unique subset of patients in relation to the COVID-19 pandemic, often presenting asymptomatically, mildly, or atypically. Manifestations of the skin may... (Review)
Review
Children are a unique subset of patients in relation to the COVID-19 pandemic, often presenting asymptomatically, mildly, or atypically. Manifestations of the skin may be a primary (or the only) presenting sign. Recognizing cutaneous manifestations of COVID-19 in the pediatric population is important to guiding precautions, testing, and management for patients and close contacts. Whereas some dermatologic signs in children overlap with those in adults, other skin findings are reported with higher frequency in children and may be clues to multisystemic sequelae. This article describes presentation, pathophysiologic theories, and management strategies for cutaneous manifestations of COVID-19 in children.
Topics: COVID-19; COVID-19 Testing; Child; Humans; Skin Diseases, Viral; Systemic Inflammatory Response Syndrome
PubMed: 34556241
DOI: 10.1016/j.det.2021.05.012 -
Clinics in Colon and Rectal Surgery Jun 2015Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor... (Review)
Review
Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor sanitation but are also found in developed nations, such as the United States, particularly in immigrants or in the setting of sporadic outbreaks. Although the majority of people are asymptomatically colonized with parasites, the clinical presentation can range from mild abdominal discomfort or diarrhea to serious complications, such as perforation or bleeding. Protozoa and helminths (worms) are the two major classes of intestinal parasites. Protozoal intestinal infections include cryptosporidiosis, cystoisosporiasis, cyclosporiasis, balantidiasis, giardiasis, amebiasis, and Chagas disease, while helminth infections include ascariasis, trichuriasis, strongyloidiasis, enterobiasis, and schistosomiasis. Intestinal parasites are predominantly small intestine pathogens but the large intestine is also frequently involved. This article highlights important aspects of parasitic infections of the colon including epidemiology, transmission, symptoms, and diagnostic methods as well as appropriate medical and surgical treatment.
PubMed: 26034403
DOI: 10.1055/s-0035-1547335 -
Cell Host & Microbe Apr 2023Candida auris and Candida albicans can result in invasive fungal diseases. And yet, these species can stably and asymptomatically colonize human skin and... (Review)
Review
Candida auris and Candida albicans can result in invasive fungal diseases. And yet, these species can stably and asymptomatically colonize human skin and gastrointestinal tracts. To consider these disparate microbial lifestyles, we first review factors shown to influence the underlying microbiome. Structured by the damage response framework, we then consider the molecular mechanisms deployed by C. albicans to switch between commensal and pathogenic lifestyles. Next, we explore this framework with C. auris to highlight how host physiology, immunity, and/or antibiotic receipt are associated with progression from colonization to infection. While treatment with antibiotics increases the risk that an individual will succumb to invasive candidiasis, the underlying mechanisms remain unclear. Here, we describe several hypotheses that may explain this phenomenon. We conclude by highlighting future directions integrating genomics with immunology to advance our understanding of invasive candidiasis and human fungal disease.
Topics: Humans; Mycobiome; Symbiosis; Host-Pathogen Interactions; Candida albicans; Candidiasis, Invasive
PubMed: 37054674
DOI: 10.1016/j.chom.2023.02.010 -
Mathematical Biosciences and... Nov 2020Asymptomatic transmission of infectious diseases has been recognized recently in several epidemics or pandemics. There is a great need to incorporate asymptomatic...
Asymptomatic transmission of infectious diseases has been recognized recently in several epidemics or pandemics. There is a great need to incorporate asymptomatic transmissions into traditional modeling of infectious diseases and to study how asymptomatic transmissions shift epidemic dynamics. In this work, we propose a compartmental model with asymptomatic transmissions for waterborne infectious diseases. We conduct a detailed analysis and numerical study with shigellosis data. Two parameters, the proportion $p$ of asymptomatic infected individuals and the proportion $k$ of asymptomatic infectious individuals who can asymptomatically transmit diseases, play major rules in the epidemic dynamics. The basic reproduction number $\mathscr{R}_{0}$ is a decreasing function of parameter $p$ when parameter $k$ is smaller than a critical value while $\mathscr{R}_{0}$ is an increasing function of $p$ when $k$ is greater than the critical value. $\mathscr{R}_{0}$ is an increasing function of $k$ for any value of $p$. When $\mathscr{R}_{0}$ passes through 1 as $p$ or $k$ varies, the dynamics of epidemics is shifted. If asymptomatic transmissions are not counted, $\mathscr{R}_{0}$ will be underestimated while the final size may be overestimated or underestimated. Our study provides a theoretical example for investigating other asymptomatic transmissions and useful information for public health measurements in waterborne infectious diseases.
Topics: Asymptomatic Infections; Basic Reproduction Number; Communicable Diseases; Epidemics; Humans; Pandemics
PubMed: 33525082
DOI: 10.3934/mbe.2021005 -
Reumatologia Clinica May 2021Uric acid has been related to a tendency to precipitate to form crystals, presenting asymptomatically, until the formation of arthritis, tophi or renal lithiasis....
BACKGROUND
Uric acid has been related to a tendency to precipitate to form crystals, presenting asymptomatically, until the formation of arthritis, tophi or renal lithiasis. Previously, the presence of asymptomatic hyperuricaemia has been associated with the presence of cardiovascular disease.
OBJECTIVES
To determine the association of complex coronary artery disease in patients with asymptomatic hyperuricaemia.
MATERIAL AND METHODS
An observational retrospective, transversal, unicentric study was conducted in a tertiary hospital in Mexico, in the period from June 2017 to March 2019. All patients admitted for coronary angiography were included; patients with gout, use of diuretics and chronic kidney disease were excluded.
RESULTS
During the study period, a total of 300 patients were collected, of which 40% presented hyperuricaemia. The patients with hyperuricaemia were older (59 vs. 63, P = .002). The group of patients with asymptomatic hyperuricaemia had a higher proportion of complex coronary lesions (64 vs. 35%, P ≤ .0001) as well as a higher SYNTAX I score (27 vs. 17, P ≤ .001). There was a higher probability of presenting complex coronary lesions in this group of patients (OR 3.4, P ≤ .0001). In addition, in the group division of uric acid levels, it was related to the presence of complex coronary lesions (Q1 = .5, P = .06), (Q2 = 2, P = .01) and (Q3 = 3, P ≤ .0001).
CONCLUSION
Asymptomatic hyperuricaemia has a higher prevalence and association of presenting complex coronary lesions.
PubMed: 31707094
DOI: 10.1016/j.reuma.2019.08.003 -
Best Practice & Research. Clinical... 2023Coeliac disease is a common autoimmune disorder induced by ingesting gluten, the protein component of wheat, barley, and rye. It is estimated that one-in-hundred people... (Review)
Review
Coeliac disease is a common autoimmune disorder induced by ingesting gluten, the protein component of wheat, barley, and rye. It is estimated that one-in-hundred people worldwide have coeliac disease, of whom the majority remain undiagnosed. Coeliac disease is characterized by a wide range of gastrointestinal and extraintestinal symptoms but can also present asymptomatically. Diagnosing coeliac disease depends on the concordance of clinical, serological and histopathological data. However, the diagnosis can be challenging and frequently overlooked. Undiagnosed coeliac disease is associated with an increased risk of complications and detrimental effects on quality of life. Early diagnosis and treatment of coeliac disease are necessary to reduce the risk of long-term complications.
Topics: Humans; Celiac Disease; Quality of Life; Triticum; Autoimmune Diseases; Glutens; Diet, Gluten-Free
PubMed: 37652646
DOI: 10.1016/j.bpg.2023.101843