Publications by authors named "Shee C"

Here, we described a unique simultaneous electrorotation (ROT) device for monitoring the rotation rate of Jurkat cells chemical stimulation without fluorescent labeling and an algorithm for estimating cell rotation rates. The device comprised two pairs of interdigitated array electrodes that were stacked orthogonally through a 20 μm-thick insulating layer with rectangular microwells. Four microelectrodes (two were patterned on the bottom of the microwells and the other two on the insulating layer) were arranged on each side of the rectangular microwells.

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According to the WHO guideline, palliative care is an integral component of COVID-19 management. The relief of physical symptoms and the provision of psychosocial support should be practiced by all healthcare workers caring for COVID-19 patients. In this review, we aim to provide a simple outline on COVID-19, suffering in COVID-19, and the role of palliative care in COVID-19.

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The N protein of phage Mu was indicated from studies in Escherichia coli to hold linear Mu chromosomes in a circular conformation by non-covalent association, and thus suggested potentially to bind DNA double-stranded ends. Because of its role in association with linear Mu DNA, we tested whether fluorescent-protein fusions to N might provide a useful tool for labeling DNA damage including double-strand break (DSB) ends in single cells. We compared N-GFP with a biochemically well documented DSB-end binding protein, the Gam protein of phage Mu, also fused to GFP.

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The ability to perform laboratory testing near the patient and with smaller blood volumes would benefit patients and physicians alike. We describe our design of a miniaturized clinical laboratory system with three components: a hardware platform (ie, the miniLab) that performs preanalytical and analytical processing steps using miniaturized sample manipulation and detection modules, an assay-configurable cartridge that provides consumable materials and assay reagents, and a server that communicates bidirectionally with the miniLab to manage assay-specific protocols and analyze, store, and report results (i.e.

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Feeding dried distillers grains with solubles (DDGS), a feed high in fat and protein, to lactating beef cows can alter milk production and composition, resulting in improved pre-weaning growth of progeny. This alteration in milk profile may consequently alter the growth and carcass composition of the offspring after weaning. Therefore, Angus×Simmental steers (n=48) whose dams were fed one of two diets supplemented with either DDGS or soybean meal (CON) from calving to mid-lactation were placed in a feedlot to determine the effects of maternal nutrition during lactation on progeny development and carcass composition.

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Multiparous Angus×Simmental cows (n=54, 5.22±2.51 years) with male progeny were fed one of two diets supplemented with either dried distillers grains with solubles (DDGS) or soybean meal (CON), from calving until day 129 postpartum (PP) to determine effects of excess protein and fat on cow performance, milk composition and calf growth.

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Balance control probably has the greatest impact on independence in activities of daily living (ADL), because it is a fundamental motor skill and prerequisite to the maintenance of a myriad of postures and mobile activities. We propose a new rehabilitation therapy to administer standing and mobile balance control training, enabled by a Mobile Robotic Assistive Balance Trainer (MRABT). The targeted group for this initial work is post stroke patients, although it can be extended to subjects with other neurological insults in the future.

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Spontaneous DNA breaks instigate genomic changes that fuel cancer and evolution, yet direct quantification of double-strand breaks (DSBs) has been limited. Predominant sources of spontaneous DSBs remain elusive. We report synthetic technology for quantifying DSBs using fluorescent-protein fusions of double-strand DNA end-binding protein, Gam of bacteriophage Mu.

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The manipulation of acid-base balance has been extensively investigated as a means of manipulating Ca homeostasis and managing milk fever in dairy cows. A low dietary cation anion difference (DCAD) increases urinary Ca, blood-ionized Ca, and responsiveness to Ca-homeostatic hormones. Very little attention has been focused on the possibility of using a low dietary DCAD to increase muscle Ca availability, calpain activity, and meat tenderness of beef cattle.

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German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (-)-α-bisabolol, farnesene, umbelliferone; 3-30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619.

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Double-stranded DNA ends, often from replication, drive genomic instability, yet their origin in non-replicating cells is unknown. Here we show that transcriptional RNA/DNA hybrids (R-loops) generate DNA ends that underlie stress-induced mutation and amplification. Depleting RNA/DNA hybrids with overproduced RNase HI reduces both genomic changes, indicating RNA/DNA hybrids as intermediates in both.

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Article Synopsis
  • The study investigates the complex network of genes involved in mutagenic DNA repair in stressed Escherichia coli, identifying at least 93 genes that play a role in this process.
  • It highlights the importance of three key stress response systems (RpoS, RpoE, and SOS) that help the bacteria sense and respond to environmental stress.
  • The findings suggest that understanding these stress responses could lead to new drug targets aimed at preventing the evolution of antibiotic-resistant pathogens.
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Mutation hotspots and showers occur across phylogeny and profoundly influence genome evolution, yet the mechanisms that produce hotspots remain obscure. We report that DNA double-strand breaks (DSBs) provoke mutation hotspots via stress-induced mutation in Escherichia coli. With tet reporters placed 2 kb to 2 Mb (half the genome) away from an I-SceI site, RpoS/DinB-dependent mutations occur maximally within the first 2 kb and decrease logarithmically to ∼60 kb.

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Evolutionary theory assumed that mutations occur constantly, gradually, and randomly over time. This formulation from the "modern synthesis" of the 1930s was embraced decades before molecular understanding of genes or mutations. Since then, our labs and others have elucidated mutation mechanisms activated by stress responses.

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Stress-induced mutation is a collection of molecular mechanisms in bacterial, yeast and human cells that promote mutagenesis specifically when cells are maladapted to their environment, i.e. when they are stressed.

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Basic ideas about the constancy and randomness of mutagenesis that drives evolution were challenged by the discovery of mutation pathways activated by stress responses. These pathways could promote evolution specifically when cells are maladapted to their environment (i.e.

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Through certain mental actions, our electroencephalogram (EEG) can be regulated to operate a brain-computer interface (BCI), which translates the EEG patterns into commands that can be used to operate devices such as prostheses. This allows paralyzed persons to gain direct brain control of the paretic limb, which could open up many possibilities for rehabilitative and assistive applications. When using a BCI neuroprosthesis in stroke, one question that has surfaced is whether stroke patients are able to produce a sufficient change in EEG that can be used as a control signal to operate a prosthesis.

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Active physiological tremor compensation instruments have been under research and development recently. The sensing unit of the instruments provides information on three degrees-of-freedom (DOF) motion of the instrument tip using accelerations provided by accelerometers placed inside the instruments. A complete vector of angular acceleration of the instrument needs to be known to obtain information on three DOF motions of the tip.

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With the increasing popularity of actuators involving smart materials like piezoelectric, control of such materials becomes important. The existence of the inherent hysteretic behavior hinders the tracking accuracy of the actuators. To make matters worse, the hysteretic behavior changes with rate.

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Accuracy in micromanipulation tasks is limited and it is important to identify various factors affecting it. This paper studies the effect of visual magnification, speed and handedness to micromanipulation accuracy using microscope and LCD screen for feedback. Magnification of visual feedback increases the accuracy, but large magnification does not provide further improvement beyond 16x.

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The recorded motion from (pathological) tremor patient may consist of the involuntary tremulous component and the intended motion. These two components have to be separated so that the actuation part will be able to suppress only the tremor. This paper proposes an algorithm to remove the intended motion by using an extended Kalman filter with the help of adaptive high-pass filter.

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Piezoelectric, magnetostrictive, and shape memory alloy actuators are gaining importance in high-frequency precision applications constrained by space. Their intrinsic hysteretic behavior makes control difficult. The Prandtl-Ishlinskii (PI) operator can model hysteresis well, albeit a major inadequacy: the inverse operator does not exist when the hysteretic curve gradient is not positive definite, i.

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