62 research outputs found
Letter to the editor
A response to Dango S, Lin R, Hennings E, Passlick B. Initial experience with a synthetic sealant PleuraSeal™ after pulmonary resections: a prospective study with retrospective case matched controls. Journal of Cardiothoracic Surgery 2010, 5:50
Mycotoxin Occurrence and Risk Assessment in Infants and Young Children (IYC) Formulated Foods in Southwest Nigeria
Mycotoxins are toxic secondary metabolites produced by fungi in foods and
feeds. Over 400 mycotoxins have been described in the literature including
aflatoxins (Afs), fumonisins (FBs), ochratoxins (OTAs), citrinin (CIT),
zearalenone (ZEN), trichothecenes (TCs), and patulin (PAT). These
mycotoxins are produced by species
of Aspergillus, Fusarium, Penicillium, Alternaria, and Claviceps. The
occurrence of these mycotoxins and other mycotoxins such as beauvericin
and moniliformin has been reported in foods consumed by infants and young
children (IYC). Aflatoxin B1, fumonisin B1, and zearalenone were reported in
stored maize grains in five agroecological zones (AEZs) of Nigeria. Also,
aflatoxins, zearalenone, and trichothecenes were reported in infant formula
samples routinely fed to IYC in Southwest Nigeria. In addition, a 100%
occurrence rate of aflatoxin was reported in household processed
complementary food samples consumed by IYC in Southwest Nigeria. In
developing countries, the contamination rate is worsened by poor agricultural
practices, low level of awareness, socioeconomic status, and lack of
enforcement of regulatory limits. Mycotoxin exposure assessment has shown
that children are most vulnerable to mycotoxins, mostly because of their lower
detoxification capacity, rapid growth, and high intake of food and water per kg
body weight. It is critical to emphasize the need for raising general knowledge
about mycotoxin exposure, incidence, and potential health repercussions in
children
Thymoma calcification: Is it clinically meaningful?
Among anterior mediastinal lesions, thymoma is the most common. Thymomas are tumors of thymic epithelial cell origin that are distinguished by inconsistent histological and biologic behavior. Chest imaging studies typically show a round or lobulated tumor in the anterior mediastinum. Calcifications in thymomas are classically punctuate or amorphous, positioned within the lesion. Chest computed tomography (CT) features suggesting higher risk thymoma consist of tumor heterogeneity, vascular involvement, lobulation, pulmonary nodules, lymphadenopathy, and pleural manifestations. Imaging findings have an imperfect ability to predict stage and prognosis for thymoma patients. Our objective is to highlight the clinical implications of thymoma calcifications on the diagnosis, clinical manifestation and prognosis. A pubmed and google search was performed using the following words: thymoma calcification, calcified thymus, mediastinal calcification, anterior mediastinal calcification, and calcified thymoma. After reviewing 370 articles, 32 eligible articles describing thymoma calcifications were found and included in this review. Although the presence of thymus calcifications was more common in patients with invasive thymomas, they were present in significant portion of non-invasive thymomas. The presence of calcifications was not a significant factor in differentiating between benign and malignant thymoma. As a result, the type, location, size or other characteristics of thymus gland calcifications were not relevant features in clinical and radiologic diagnosis of thymoma. The histopathological diagnosis is still the only possible way to confirm the neoplastic nature of thymoma. All types of thymomas should be evaluated and managed independently of the presence of calcifications
Regulation of CEACAM1 transcription in human breast epithelial cells
<p>Abstract</p> <p>Background</p> <p>Carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) is a transmembrane protein with multiple functions in different cell types. CEACAM1 expression is frequently mis-regulated in cancer, with down-regulation reported in several tumors of epithelial origin and <it>de novo </it>expression of CEACAM1 in lung cancer and malignant melanoma. In this report we analyzed the regulation of CEACAM1 expression in three breast cancer cell lines that varied in CEACAM1 expression from none (MCF7) to moderate (MDA-MB-468) to high (MCF10A, comparable to normal breast).</p> <p>Results</p> <p>Using <it>in vivo </it>footprinting and chromatin immunoprecipitation experiments we show that the <it>CEACAM1 </it>proximal promoter in breast cells is bound in its active state by SP1, USF1/USF2, and IRF1/2. When down-regulated the <it>CEACAM1 </it>promoter remains accessible to USF2 and partially accessible to USF1. Interferon-γ up-regulates CEACAM1 mRNA by a mechanism involving further induction of IRF-1 and USF1 binding at the promoter. As predicted by this analysis, silencing of IRF1 and USF1 but not USF2 by RNAi resulted in a significant decrease in CEACAM1 protein expression in MDA-MB-468 cells. The inactive <it>CEACAM1 </it>promoter in MCF7 cells exhibits decreased histone acetylation at the promoter region, with no evidence of H3K9 or H3K27 trimethylation, histone modifications often linked to condensed chromatin structure.</p> <p>Conclusions</p> <p>Our data suggest that transcription activators USF1 and IRF1 interact to modulate CEACAM1 expression and that the chromatin structure of the promoter is likely maintained in a poised state that can promote rapid induction under appropriate conditions.</p
Nanochitosan derived from marine bacteria
Nanochitosans are polysaccharides produced by the alkalescent
deacetylation of chitin and comprise a series of 2-deoxy-2
(acetylamino) glucose linked by ß-(1-4) glycosidic linkages. These are
naturally formed from the deacetylation of shellfish shells and the
exoskeleton of aquatic arthropods and crustaceans. Reports of
chitosan production from unicellular marine bacteria inhabiting the
sea, and possessing distinct animal- and plant-like characteristics
abound. This capacity to synthesize chitosan from chitin arises from
response to stress under extreme environmental conditions, as a
means of survival. Consequently, the microencapsulation of these
nanocarriers results in new and improved chitosan nanoparticles,
nanochitosan. This nontoxic bioactive material which can serve as an
antibacterial agent, gene delivery vector as well as carrier for protein
and drug release as compared with chitosan, is limited by its
nonspecific molecular weight and higher composition of deacetylated
chitin. This chapter highlights the biology and diversity of
nanochitosan-producing marine bacteria, including the factors
influencing their activities, survival, and distribution. More so, the
applications of marine bacterial nanochitosans in transfection and
gene delivery; wound healing and drug delivery; feed supplement
development and antimicrobial activity are discussed
Utilization of nanochitosan for enzyme immobilization of aquatic and animal-based food packages
Studies have identified the properties of enzymes, functionalized molecules, and compounds in food industry applications as edible coatings and encapsulations, that assure prolonged food quality and standards. These molecules present benefits of longer shelf-life by delayed deterioration and inhibition of the proliferation of spoilage and mycotoxigenic microorganisms. However, challenges of reduced nutrient levels, miniaturized size, and low chemical stability remain concerning. Chitosan polymers naturally formed from the deacetylation of shellfish shells and exoskeletons of aquatic arthropods and crustaceans offer improved benefits when functionalized into nanoparticles as nanochitosans. These polysaccharides produced by the alkalescent deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. This chapter considers the health impacts and
Nanochitosan derived from marine bacteria
Nanochitosans are polysaccharides produced by the alkalescent deacetylation of chitin and comprise
a series of 2‐deoxy‐2 (acetylamino) glucose linked by ß‐(1‐4) glycosidic linkages. These are naturally
formed from the deacetylation of shellfish shells and the exoskeleton of aquatic arthropods and
crustaceans. Reports of chitosan production from unicellular marine bacteria inhabiting the sea, and
possessing distinct animal‐ and plant‐like characteristics abound. This capacity to synthesize chitosan
from chitin arises from response to stress under extreme environmental conditions, as a means of
survival. Consequently, the microencapsulation of these nanocarriers results in new and improved
chitosan nanoparticles, nanochitosan. This nontoxic bioactive material which can serve as an
antibacterial agent, gene delivery vector as well as carrier for protein and drug release as compared
with chitosan, is limited by its nonspecific molecular weight and higher composition of deacetylated
chitin. This chapter highlights the biology and diversity of nanochitosan‐producing marine bacteria,
including the factors influencing their activities, survival, and distribution. More so, the applications
of marine bacterial nanochitosans in transfection and gene delivery; wound healing and drug
delivery; feed supplement development and antimicrobial activity are discussed
Chapter 21 - Utilization of nanochitosan in the sterilization of ponds and water treatment for aquaculture
Water pollution constitutes the leading cause of infant mortality,
neonatal deformities, and shrinkage of man’s average life expectancy.
Pollutants come from point and nonpoint sources; and water pollution
arises from the discharge of wastewater containing undesirable
impurities used for domestic, agricultural, and industrial purposes.
More so, high nutrient and wastewater runoffs from fish production
systems contribute to the fouling and eutrophication of recipient water
bodies. Hence, aquaculture which is inextricably linked to the natural
environment is challenged by the dearth of appropriate water quantity
and quality, militating against fish, and fishery production.
Nanochitosans as polysaccharides produced by the alkalescent
deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino)
glucose linked by ß-(1-4) glycosidic linkages. They are naturally
formed from the deacetylation of shellfish shells and exoskeletons of
aquatic arthropods and crustaceans. The unique attributes of chitin
confer a wide range of biotechnological applications on the polymer,
observed in flocculation as a wastewater treatment and purification
route initiated by chitosan. This chapter highlights nanochitosan properties of aquaculture relevance; and elucidates the purification
potentials of nanochitosan, compared to inorganic coagulants and
organic polymeric flocculants. Effects of chitosan on contaminants and
microorganisms, as well as applications in fish pathogens detection,
fish disease diagnosis, and control are discussed
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