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Journal of Gastrointestinal Oncology Feb 2019Gastrointestinal stromal tumors (GISTs) are rare neoplasms of the gastrointestinal tract associated with high rates of malignant transformation. Most GISTs present... (Review)
Review
Gastrointestinal stromal tumors (GISTs) are rare neoplasms of the gastrointestinal tract associated with high rates of malignant transformation. Most GISTs present asymptomatically. They are best identified by computed tomography (CT) scan and most stain positive for CD117 (C-Kit), CD34, and/or DOG-1. There have been many risk stratification classifications systems which are calculated based on tumor size, mitotic rate, location, and perforation. The approaches to treating GISTs are to resect primary low-risk tumors, resect high-risk primary or metastatic tumors with imatinib 400 mg daily for 12 months, or if the tumor is unresectable, neoadjuvant imatinib 400 mg daily followed by surgical resection is recommended. Sunitinib is required for KIT exon 9, 13, and 14 mutations, while ponatinib is used for exon 17 mutations and regorafenib for highly refractory tumors. High-risk tumors should be monitored for recurrence with serial abdominal CT scans. Radiofrequency ablation has shown to be effective when surgery is not suitable. Newer therapies of ipilimumab, nivolumab, and endoscopic ultrasound alcohol ablation have shown promising results. This report addresses the epidemiology, clinical presentation, diagnostic imaging, histologic diagnosis, classification and risk stratification, staging and grading, surgical treatment, adjuvant treatment, and metastasis of GISTs.
PubMed: 30788170
DOI: 10.21037/jgo.2018.08.20 -
Nature Reviews. Microbiology Jan 2018Candida albicans is among the most prevalent fungal species of the human microbiota and asymptomatically colonizes healthy individuals. However, it is also an... (Review)
Review
Candida albicans is among the most prevalent fungal species of the human microbiota and asymptomatically colonizes healthy individuals. However, it is also an opportunistic pathogen that can cause severe, and often fatal, bloodstream infections. The medical impact of C. albicans typically depends on its ability to form biofilms, which are closely packed communities of cells that attach to surfaces, such as tissues and implanted medical devices. In this Review, we provide an overview of the processes involved in the formation of C. albicans biofilms and discuss the core transcriptional network that regulates biofilm development. We also consider some of the advantages that biofilms provide to C. albicans in comparison with planktonic growth and explore polymicrobial biofilms that are formed by C. albicans and certain bacterial species.
Topics: Antifungal Agents; Biofilms; Candida albicans; Drug Resistance, Fungal; Gene Expression Regulation, Fungal; Gene Regulatory Networks; Humans
PubMed: 29062072
DOI: 10.1038/nrmicro.2017.107 -
Frontiers in Molecular Biosciences 2016Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial... (Review)
Review
Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of <200 pmol/L) presents asymptomatically or with rather subtle generic symptoms that oftentimes are mistakenly ascribed to unrelated disorders. Numerous studies have now established that serum vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders.
PubMed: 27446930
DOI: 10.3389/fmolb.2016.00027 -
The Lancet. Infectious Diseases Jan 2020Creutzfeldt-Jakob disease (CJD) is a fatal disease presenting with rapidly progressive dementia, and most patients die within a year of clinical onset. CJD poses a...
Creutzfeldt-Jakob disease (CJD) is a fatal disease presenting with rapidly progressive dementia, and most patients die within a year of clinical onset. CJD poses a potential risk of iatrogenic transmission, as it can incubate asymptomatically in humans for decades before becoming clinically apparent. In this Review, we sought evidence to understand the current iatrogenic risk of CJD to public health by examining global evidence on all forms of CJD, including clinical incidence and prevalence of subclinical disease. We found that although CJD, particularly iatrogenic CJD, is rare, the incidence of sporadic CJD is increasing. Incubation periods as long as 40 years have been observed, and all genotypes have now been shown to be susceptible to CJD. Clinicians and surveillance programmes should maintain awareness of CJD to mitigate future incidences of its transmission. Awareness is particularly relevant for sporadic CJD, which occurs in older people in whom clinical presentation could resemble rapidly developing dementia.
Topics: Adult; Aged; Aged, 80 and over; Creutzfeldt-Jakob Syndrome; Female; Humans; Iatrogenic Disease; Incidence; Infectious Disease Incubation Period; Male; Middle Aged; Prevalence; Risk Assessment; Young Adult
PubMed: 31876504
DOI: 10.1016/S1473-3099(19)30615-2 -
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 -
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 -
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 -
Research and Reports in Tropical... 2021Strongyloidiasis is a parasitic infection distributed worldwide, with an estimated 614 million people infected. Strongyloidiasis usually presents asymptomatically or... (Review)
Review
Strongyloidiasis is a parasitic infection distributed worldwide, with an estimated 614 million people infected. Strongyloidiasis usually presents asymptomatically or with aspecific and mild clinical symptoms, mainly cutaneous, respiratory, or gastrointestinal. Disseminated disease and hyperinfection syndrome are the most serious complications, have a high mortality rate, usually occur in immunosuppressed patients, and are particularly associated with the use of corticosteroids. Strongyloidiasis is the most neglected of the neglected diseases, and its occurrence in pregnancy has been neglected and understudied. In this review, we focus on the effects of strongyloidiasis during pregnancy and highlight the knowledge shortage and the need for more research on the subject. There are few studies addressing strongyloidiasis prevalence during pregnancy and hyperinfection incidence during pregnancy is practically unknown, with only isolated case reports published. Although data are scarce, the infection has been associated with developmental disabilities and anemia during pregnancy, while hyperinfection may cause both maternal and neonatal death. Data on the best screening and diagnostic strategies during pregnancy are lacking. There is insufficient evidence on ivermectin safety in pregnancy, complicating treatment recommendations.
PubMed: 34584485
DOI: 10.2147/RRTM.S282268