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Liver cancer (primary or metastatic) accounts for nearly 10% of all cancers in the US alone, the ... more Liver cancer (primary or metastatic) accounts for nearly 10% of all cancers in the US alone, the incidence being even greater in eastern countries. Treatment modalities involve surgery, chemotherapy, thermal ablation using radiofrequency or microwave probes and radiomicrosphere therapy (RMT) with Y-90 microspheres. For treatment planning Tc-99m-macro aggregated albumin (MAA) is infused into the proper hepatic artery and a perfusion scintigraphy is performed. Significant difference in size, shape, and other properties of the MAA and the Y-90 microspheres complicates the treatment planning because the MAA particles cannot be expected to distribute the same as the Y-90 microspheres. There is a need for biodegradable microspheres with biological half life ≤48 hours. Microspheres must be labeled with a PET isotope with > 90% yield and ≥90 % in vivo stability after 4 h. CHSg-NOTA microparticles were labeled with Ga successfully with more than 90% yield at room temperature. Reaction kin...
ASME 2012 Summer Bioengineering Conference, Parts A and B, 2012
Different muscle groups function in a synchronized and coordinated manner to perform a given task... more Different muscle groups function in a synchronized and coordinated manner to perform a given task, wherein the activity of one muscle group affects that of another (1, 3). Osteoarthritis (OA) is a common, chronic joint disease characterized by pain, disability and progressive loss of function. It is the most common musculoskeletal complaint worldwide and is associated with significant health and welfare costs (2, 7). The knee is the most frequently affected joint of the lower limb and prevalence of knee OA increases with age (6). Several studies have shown that muscle recruitment patterns and neuromuscular efficiency are different for patients with OA compared to normal controls during simple closed chain activities (4). However, no studies have investigated frontal plane control or the modulation of control due to, for example, a change in time or distance in OA (5).
2013 29th Southern Biomedical Engineering Conference, 2013
ABSTRACT Older adults can develop neuromuscular deficiencies. We tested the hypothesis that these... more ABSTRACT Older adults can develop neuromuscular deficiencies. We tested the hypothesis that these deficiencies could be reflected in altered neuromuscular control during normal daily tasks. Hence, we compared the ability to modulate ground reaction force (GRF) during lateral stepping (LS) from different step heights between younger and older adults. Kinetic data was obtained from younger (23-33 yrs, n=5) and older (57-65 yrs, n=5) male and female subjects. They stood on top of two 4-inch/8-inch high platforms. Each platform was placed on separate force plates. The subjects were instructed to step down laterally using their non-dominant leg and then step up to the original position. GRF and joint-angle kinematics of both limbs were recorded for the two-step heights. The time (% total) to achieve maximum amount of force (as % body weight) exerted was calculated using data from the average of three LS trials per subject. It was significantly different between males (32.75±1.57) and females (35.75±1.28) (p=0.012) or between young (33.479±1.43) and old (35.021±1.43) (p=0.018) using a three way repeated measures ANOVA comparing step height (4 inch, 8 inch), gender (male, female), and age (young, old.) According to the data, neuromuscular control of the LS task is affected by age and gender.
Journal of Pharmacy and Bioallied Sciences, 2013
Osteoarthritis (OA) is progressive joint disease characterized by joint inflammation and a repara... more Osteoarthritis (OA) is progressive joint disease characterized by joint inflammation and a reparative bone response and is one of the top five most disabling conditions that affects more than one-third of persons > 65 years of age, with an average estimation of about 30 million Americans currently affected by this disease. Global estimates reveal more than 100 million people are affected by OA. The financial expenditures for the care of persons with OA are estimated at a total annual national cost estimate of 15.5−15.5-15.5−28.6 billion per year. As the number of people >65 years increases, so does the prevalence of OA and the need for cost-effective treatment and care. Developing a treatment strategy which encompasses the underlying physiology of degenerative joint disease is crucial, but it should be considerate to the different age ranges and different population needs. This paper focuses on different exercise and treatment protocols (pharmacological and non-pharmacological), the outcomes of a rehabilitation center, clinician-directed program versus an at home directed individual program to view what parameters are best at reducing pain, increasing functional independence, and reducing cost for persons diagnosed with knee OA.
Different muscle groups function in synchrony and coordination to perform a given task, wherein t... more Different muscle groups function in synchrony and coordination to perform a given task, wherein the activity of one muscle group closely affects that of another [1,3]. Osteoarthritis (OA), a chronic joint disease, is the most common musculoskeletal complaint worldwide characterized by pain, disability and progressive loss of function. It is associated with significant health and welfare costs [2,7]. The knee is the most frequently affected lower limb joint and prevalence of knee OA increases with age [6]. Several studies have shown that muscle recruitment patterns and neuromuscular efficiency are different for patients with OA compared to normal controls during simple closed chain activities [4,5]. However, no studies have investigated frontal plane control or the modulation of control due to, for example, a change in time or distance in OA [5,6]. This paper reports the results of a pilot study with healthy subjects to determine muscle activation patterns (electromyogram, EMG), and modulation of these patterns, in a frontal plane step initiation task.
International Journal of Radiation Oncology*Biology*Physics
Older adults may have trouble when performing activities of daily living due to decrease in physi... more Older adults may have trouble when performing activities of daily living due to decrease in physical strength and degradation of neuromotor and musculoskeletal function. Motor activation patterns during Lateral Step Down and Step Up from 4-inch and 8-inch step heights was assessed in younger (n=8, 24.4 years) and older adults (n=8, 58.9 years) using joint angle kinematics and electromyography of lower extremity muscles. Ground reaction forces were used to ascertain the loading, stabilization and unloading phases of the tasks. Older adults had an altered muscle activation sequence and significantly longer muscle bursts during loading for the tibialis anterior, gastrocnemius, vastus medialis, bicep femoris, gluteus medius and gluteus maximus muscles of the stationary leg. They also demonstrated a significantly larger swing time (579.1 ms vs. 444.8 ms) during the step down task for the moving leg. The novel data suggests presence of age-related differences in motor coordination during lateral stepping. vii
This data collection contains three dimensional high-resolution (3D) fan-beam CT scans collected ... more This data collection contains three dimensional high-resolution (3D) fan-beam CT scans collected during pre-treatment, mid-treatment, and post-treatment using a Siemens 16-slice CT scanner with standard clinical protocol for 31 head-and-neck squamous cell carcinoma (HNSCC) patients. Patients underwent radiotherapy treatment to a total dose of 58-70 Gy, using daily 2-2.20 Gy, fractions for 30-35 fractions. The pre-treatment planning CT scans were performed with a median of 13 days (range: 2-27) before treatment, the mid-treatment CT was performed at fraction 17 (range: 8-26), and the post-treatment CT around fraction 30 (range: 26th fraction - 21 weeks post treatment). In addition to the imaging data, the data sets contain contours of anatomical structures for radiotherapy. The contours were generated by the attending radiation oncologists for treatment planning purposes, and subsequently treatment plans were generated with Eclipse® (Varian Medical Systems, Inc., Palo Alto, CA) treat...
Liver cancer (primary or metastatic) accounts for nearly 10% of all cancers in the US alone, the ... more Liver cancer (primary or metastatic) accounts for nearly 10% of all cancers in the US alone, the incidence being even greater in eastern countries. Treatment modalities involve surgery, chemotherapy, thermal ablation using radiofrequency or microwave probes and radiomicrosphere therapy (RMT) with Y-90 microspheres. For treatment planning Tc-99m-macro aggregated albumin (MAA) is infused into the proper hepatic artery and a perfusion scintigraphy is performed. Significant difference in size, shape, and other properties of the MAA and the Y-90 microspheres complicates the treatment planning because the MAA particles cannot be expected to distribute the same as the Y-90 microspheres. There is a need for biodegradable microspheres with biological half life ≤48 hours. Microspheres must be labeled with a PET isotope with > 90% yield and ≥90 % in vivo stability after 4 h. CHSg-NOTA microparticles were labeled with Ga successfully with more than 90% yield at room temperature. Reaction kin...
ASME 2012 Summer Bioengineering Conference, Parts A and B, 2012
Different muscle groups function in a synchronized and coordinated manner to perform a given task... more Different muscle groups function in a synchronized and coordinated manner to perform a given task, wherein the activity of one muscle group affects that of another (1, 3). Osteoarthritis (OA) is a common, chronic joint disease characterized by pain, disability and progressive loss of function. It is the most common musculoskeletal complaint worldwide and is associated with significant health and welfare costs (2, 7). The knee is the most frequently affected joint of the lower limb and prevalence of knee OA increases with age (6). Several studies have shown that muscle recruitment patterns and neuromuscular efficiency are different for patients with OA compared to normal controls during simple closed chain activities (4). However, no studies have investigated frontal plane control or the modulation of control due to, for example, a change in time or distance in OA (5).
2013 29th Southern Biomedical Engineering Conference, 2013
ABSTRACT Older adults can develop neuromuscular deficiencies. We tested the hypothesis that these... more ABSTRACT Older adults can develop neuromuscular deficiencies. We tested the hypothesis that these deficiencies could be reflected in altered neuromuscular control during normal daily tasks. Hence, we compared the ability to modulate ground reaction force (GRF) during lateral stepping (LS) from different step heights between younger and older adults. Kinetic data was obtained from younger (23-33 yrs, n=5) and older (57-65 yrs, n=5) male and female subjects. They stood on top of two 4-inch/8-inch high platforms. Each platform was placed on separate force plates. The subjects were instructed to step down laterally using their non-dominant leg and then step up to the original position. GRF and joint-angle kinematics of both limbs were recorded for the two-step heights. The time (% total) to achieve maximum amount of force (as % body weight) exerted was calculated using data from the average of three LS trials per subject. It was significantly different between males (32.75±1.57) and females (35.75±1.28) (p=0.012) or between young (33.479±1.43) and old (35.021±1.43) (p=0.018) using a three way repeated measures ANOVA comparing step height (4 inch, 8 inch), gender (male, female), and age (young, old.) According to the data, neuromuscular control of the LS task is affected by age and gender.
Journal of Pharmacy and Bioallied Sciences, 2013
Osteoarthritis (OA) is progressive joint disease characterized by joint inflammation and a repara... more Osteoarthritis (OA) is progressive joint disease characterized by joint inflammation and a reparative bone response and is one of the top five most disabling conditions that affects more than one-third of persons > 65 years of age, with an average estimation of about 30 million Americans currently affected by this disease. Global estimates reveal more than 100 million people are affected by OA. The financial expenditures for the care of persons with OA are estimated at a total annual national cost estimate of 15.5−15.5-15.5−28.6 billion per year. As the number of people >65 years increases, so does the prevalence of OA and the need for cost-effective treatment and care. Developing a treatment strategy which encompasses the underlying physiology of degenerative joint disease is crucial, but it should be considerate to the different age ranges and different population needs. This paper focuses on different exercise and treatment protocols (pharmacological and non-pharmacological), the outcomes of a rehabilitation center, clinician-directed program versus an at home directed individual program to view what parameters are best at reducing pain, increasing functional independence, and reducing cost for persons diagnosed with knee OA.
Different muscle groups function in synchrony and coordination to perform a given task, wherein t... more Different muscle groups function in synchrony and coordination to perform a given task, wherein the activity of one muscle group closely affects that of another [1,3]. Osteoarthritis (OA), a chronic joint disease, is the most common musculoskeletal complaint worldwide characterized by pain, disability and progressive loss of function. It is associated with significant health and welfare costs [2,7]. The knee is the most frequently affected lower limb joint and prevalence of knee OA increases with age [6]. Several studies have shown that muscle recruitment patterns and neuromuscular efficiency are different for patients with OA compared to normal controls during simple closed chain activities [4,5]. However, no studies have investigated frontal plane control or the modulation of control due to, for example, a change in time or distance in OA [5,6]. This paper reports the results of a pilot study with healthy subjects to determine muscle activation patterns (electromyogram, EMG), and modulation of these patterns, in a frontal plane step initiation task.
International Journal of Radiation Oncology*Biology*Physics
Older adults may have trouble when performing activities of daily living due to decrease in physi... more Older adults may have trouble when performing activities of daily living due to decrease in physical strength and degradation of neuromotor and musculoskeletal function. Motor activation patterns during Lateral Step Down and Step Up from 4-inch and 8-inch step heights was assessed in younger (n=8, 24.4 years) and older adults (n=8, 58.9 years) using joint angle kinematics and electromyography of lower extremity muscles. Ground reaction forces were used to ascertain the loading, stabilization and unloading phases of the tasks. Older adults had an altered muscle activation sequence and significantly longer muscle bursts during loading for the tibialis anterior, gastrocnemius, vastus medialis, bicep femoris, gluteus medius and gluteus maximus muscles of the stationary leg. They also demonstrated a significantly larger swing time (579.1 ms vs. 444.8 ms) during the step down task for the moving leg. The novel data suggests presence of age-related differences in motor coordination during lateral stepping. vii
This data collection contains three dimensional high-resolution (3D) fan-beam CT scans collected ... more This data collection contains three dimensional high-resolution (3D) fan-beam CT scans collected during pre-treatment, mid-treatment, and post-treatment using a Siemens 16-slice CT scanner with standard clinical protocol for 31 head-and-neck squamous cell carcinoma (HNSCC) patients. Patients underwent radiotherapy treatment to a total dose of 58-70 Gy, using daily 2-2.20 Gy, fractions for 30-35 fractions. The pre-treatment planning CT scans were performed with a median of 13 days (range: 2-27) before treatment, the mid-treatment CT was performed at fraction 17 (range: 8-26), and the post-treatment CT around fraction 30 (range: 26th fraction - 21 weeks post treatment). In addition to the imaging data, the data sets contain contours of anatomical structures for radiotherapy. The contours were generated by the attending radiation oncologists for treatment planning purposes, and subsequently treatment plans were generated with Eclipse® (Varian Medical Systems, Inc., Palo Alto, CA) treat...