Model studies for isolation of G-quadruplex-forming DNA sequences through a pull-down strategy with macrocyclic polyoxazole

G-quadruplexes (G4s) are non-B DNA structures present in guanine-rich regions of gene regulatory areas, promoters and CpG islands, but their occurrence and functions remain incompletely understood. Thus, methodology to identify G4 sequences is needed. Here, we describe the synthesis of a novel cyclic hepta-oxazole compound, L1Bio-7OTD (1), bearing a biotin affinity-tag as a tool to pull down G4 structures from mixtures of G4-forming and non G4-forming DNA sequences. We confirmed that it could pull down G4s associated with telomeres, bcl-2 gene, and c-kit gene.     

Concentration of arsenic in groundwater,vegetables, human hair and nails in mining site in the Northern Thai Nguyen province,Vietnam: human exposure and risks assessment

This study was aimed to examine the risk of chronic arsenic (As) exposure for the residents living in Nui Phao, Thai Nguyen in the northern Vietnam. Groundwater, vegetables, human hair, and nail samples were collected from volunteers living in Nui Phao. The results revealed that 75% of the groundwater samples had As exceeding the World Health Organization (WHO) drinking water guideline of 10 µg L^?1. The result of As concentration for most of the vegetable samples was greater than the WHO/FAO safe (0.1?mg kg^?1). The result of hair and nail samples in this study showed that 3.5 and 20% of the samples had As concentration exceeding the level of As toxicity in hair and nails, respectively. The result of health risks indicated that the potential health risk of As contamination is greater for groundwater than vegetables. The total hazard quotient (HQ) value through vegetables ingestion and drinking water exceeded 1.0 suggesting potential health risk for local residents. The calculation of potential carcinogenic risk through both consumption of vegetables and drinking water was low cancer risk in adults. Other food sources and the exposure pathways are needed to exactly assess health risks in this area.     

Resolving Cell Fate Decisions during Somatic Cell Reprogramming by Single-Cell RNA-Seq

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The Biological Applications of Two Aggregation‐Induced Emission Luminogens

Fluorescence imaging, as a commonly used scientific tool, is widely applied in various biomedical and material structures through visualization technology. Highly selective and sensitive luminescent biological probes, as well as those with good water solubility, are urgently needed for biomedical research. In contrast to the traditional aggregation‐caused quenching of fluorescence, in the unique phenomenon of aggregation‐induced emission (AIE), the individual luminogens have extremely weak or no emissivity because they each have free intramolecular motion; however, when they form aggregates, these components immediately “light up”. Since the discovery of “turn‐on” mechanism, researchers have been studying and applying AIE in a variety of fields to develop more sensitive, selective, and efficient strategies for the AIE dyes. There are numerous advantages to the use of AIE‐based methods, including low background interference, strong contrast, high performance in intracellular imaging, and the ability for long‐term monitoring in vivo. In this review, two typical examples of AIEgens, TPE‐Cy and TPE‐Ph‐In, are described, including their structure properties and applications. Recent progress in the biological applications is mainly focused on. Undoubtedly, in the near future, an increasing number of encouraging and practical ideas will promote the development of more AIEgens for broad use in biomedical applications.     

Single-Cell Heterogeneity Analysis and CRISPR Screen Identify Key β-Cell-Specific Disease Genes

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Effect of ferrous ion on the biological activity in a UASB reactor: mathematical modeling and verification

The effect of ferrous ion on the biological activity in a upflow anaerobic sludge blanket (UASB) reactor was studied. A mathematical model was developed and validated in order to simulate the dynamic behavior of a UASB reactor. This model took into consideration of all the biological and physicochemical reactions. The model was able to simulate the accumulation of iron in the sludge bed and its effect on the biological activity of the anaerobic sludge. A significant increase in the maximum uptake rate of methanogens and acidogens was revealed when iron was supplemented to the UASB reactor. The addition of ferrous iron induced a stable and excellent COD conversion rate. The model can be a useful tool for the prediction of process performance in the future and can be used to assist in the operation of biogas plants. The ferrous ion addition proved to enhance the biological activity of UASB sludge. Thus, the model can be used for the design of treatment plants that will take advantage of the benefits of iron addition.     

Osteoactivin fragments produced by ectodomain shedding induce MMP-3 expression via ERK pathway in mouse NIH-3T3 fibroblasts

Intact osteoactivin, a novel type I membrane glycoprotein, were shed at a dibasic motif in the juxtamembrane region in C2C12 myoblasts. Extracellular fragments were secreted into the culture media by a putative metalloprotease. Extracellular fragments of osteoactivin, but not control protein, induced matrix metalloprotease-3 (MMP-3) expression in NIH-3T3 fibroblasts. Epidermal growth factor (ERK) kinase inhibitors inhibited the osteoactivin-mediated MMP-3 expression, whereas the extracellular fragment of osteoactivin activated ERK1/2 and p38 in the mitogen-activated protein kinase pathway. Our results suggest that the extracellular fragments of osteoactivin produced by shedding act as a growth factor to induce MMP-3 expression via the ERK pathway in fibroblasts.     

Birth defects interstate data exchange: a battle worth fighting?

BACKGROUND: Regardless of where infants and children are delivered, diagnosed, or treated, an important aspect of population-based birth defects surveillance is ensuring the inclusion of children with birth defects in the catchment area. However, little is known as to how the lack of interstate birth defects data exchange affects program surveillance, monitoring, prevention, and referral activities. The study objectives were to determine the status of interstate birth defects data exchange agreements and to quantify statewide data on resident births occurring in nonresident states. METHODS: In 2004, surveys were distributed to all population-based birth defects programs in the United States to determine: 1) the types of interstate birth defects data exchange agreements that exist among birth defects programs, 2) perceived barriers in establishing exchange agreements, and 3) the extent to which out-of-state births affect a program's catchment area. The National Center for Health Statistics (NCHS) data for 2002 on live birth residency were used to determine the actual frequency of out-of-state live birth occurrence. RESULTS: Of the 52 states and territories that were surveyed, 65% (n = 34) responded. Approximately 21% (n = 7) of those that responded had an interstate data exchange agreement that allowed sharing of birth defects data with another state or a facility within another state. Approximately 53% (n = 18) of responding states indicated plans to develop an interstate birth defects data exchange agreement with other states, hospitals, or both. The NCHS data showed that the actual percentage of resident out-of-state live births ranged from 0.16 to 11.51. NCHS data also reveal that 78% of states would be able to capture >75% of their out-of-state births by sharing data on out-of-state births with the three neighboring states ranking highest in terms of such occurrences. CONCLUSIONS: Few states have interstate birth defects data exchange agreements, though all states have resident births occurring out of state. While suggestive, data beyond residency of live births are needed to quantify the degree to which the objectives of state-based birth defects programs are compromised. Resources exist to guide programs in establishing interstate data exchange agreements. Efforts to establish such agreements with only a few neighboring states could be a large step toward improving birth defects surveillance on a state, regional, and national level.