Use of needles for multiple injections of drugs, such as insulin for diabetes, can be painful. As a result, prescribed drug noncompliance can results in severe medical complications. In previous studies, ultrasound me...
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Use of needles for multiple injections of drugs, such as insulin for diabetes, can be painful. As a result, prescribed drug noncompliance can results in severe medical complications. In previous studies, ultrasound mediated transdermal drug delivery has shown a promising potential as a method for noninvasive drug administration. Yet for prospective human application, a milestone to a practical clinical device of this research requires that the efficacy of the cymbal array be demonstrated on animals larger than rats and rabbits. Larger and possessing a blood volume similar to humans, pig is an appropriate animal model for further experimentation in evaluating the practicability of this ultrasound device. Six Yorkshire pigs (100-140 lbs) were divided into two groups. As the control (n = 3), the first group did not receive any ultrasound exposure with the insulin. The second group (n = 3) was treated with ultrasound and insulin at 20 kHz with an I sptp = 100 mW/cm 2 at a 20% duty cycle for 60 minutes. With the pigs in lateral recumbency after anesthesia, the ultrasound transducer with insulin was placed on the axillary area of the pig. At the beginning and every 15 minutes up to 90 minutes, the blood glucose level was determined using a glucose monitoring system. To compare the results of individual animals, the change of blood glucose level was normalized to each animal's initial glucose value at the start of the experiment. Although each animal had a different initial glucose level, the mean and standard error for the six animals was 146plusmn13 mg/dl (Figure 1). For the control group, the blood glucose level increased to 31plusmn21 mg/dl compared to the initial baseline over the 90 minute experiment. However for the ultrasound with insulin treated group, the glucose level decreased to -72plusmn5 mg/dl at 60 minutes (p < 0.05) and continued to decreased to -91plusmn23 mg/dl in 90 minutes (p < 0.05). Results demonstrate a promising pre-clinical outcome for the low p
Faculty members from Georgia Tech's School of Electrical and Computer Engineering (ECE) have worked jointly with engineers from National Instruments (NI) to develop a new freshman engineering course. This course i...
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Nucleic acid based analysis has an important role to play in many critical applications such as medical diagnostics,environmental monitoring and food safety *** the available analytical tools,real time polymerase chai...
Nucleic acid based analysis has an important role to play in many critical applications such as medical diagnostics,environmental monitoring and food safety *** the available analytical tools,real time polymerase chain reaction(PCR)has been widely adopted as a viable technique for rapid detection and quantification of trace nucleic acid analytes[1].One challenge to
Studies have shown that ultrasound mediated transdermal drug delivery offers a promising potential for needle-less insulin delivery for diabetes treatment. Arrays of cymbal transducers have been shown to be effective ...
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Studies have shown that ultrasound mediated transdermal drug delivery offers a promising potential for needle-less insulin delivery for diabetes treatment. Arrays of cymbal transducers have been shown to be effective in delivering therapeutic levels of insulin to decrease hyperglycemic glucose levels in rats, rabbits and pigs. To improve delivery efficiency of the cymbal arrays, an increase in the spatial intensity field without increasing the size the device or Isptp was desired. A 3 times 1 rectangular cymbal array was designed for this purpose. Rectangular cymbals maximized packing density and allowed the flexural cap resonance and the ceramic length mode resonance frequencies to be designed closer in frequency. Bringing the cap and ceramic resonances closer together increased the transmitting power and improved the electrical efficiency. By using higher order modes excited in the cap while operating at the first ceramic resonance frequency, the intensity spatial area was increased compared to the circular array. With a similar intensity (I sptp ap 50 mW/cm ), our goal was to determine if the 3 times 1 rectangular cymbal array could perform significantly better than the 3 times 3 circular array for blood glucose reduction in hyperglycemic rabbits. Nine New Zealand White rabbit (ap 4.0 kg) experiments were performed in three groups: control (n = 3) and ultrasound exposure with the 3 times 3 circular cymbal array (n = 3) or 3 times 1 rectangular cymbal array (n = 3). The rabbits were anesthetized and their thigh area was shaved for the exposure. A water tight reservoir which held the insulin was fastened between the rabbit's thigh and the ultrasound arrays. At the beginning of the experiment and every 15 minutes for 90 minutes, 0.3 ml of blood was collected from the ear vein to determine the glucose level (mg/dl) using a glucose monitoring system. For comparison between individual rabbits, the change in the blood glucose level was normalized to their initial basel
Vascular smooth muscle cells (SMCs) populate in the media of the blood vessel, and play an important role in the control of vasoactivity and the remodeling of the vessel wall. Blood vessels are constantly subjected to...
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The natural extracellular matrix (ECM) is a complex structure that is built to meet the specific requirements of the tissue and organ. Primarily consisting of nanometer diameter fibrils, ECM may contain other vital su...
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