Medical Devices
Content
Tagline What makes you an expert in the Healthcare specialty?
In addition to developing life-saving treatments while working at a major healthcare
company, I am staying current by pursuing a PhD in biomedical engineering.
Prompt Discuss one of the following in 200-300 words:
Discuss a medical condition, and some treatments for it (including herbal
supplements, and non drug treatments etc.)
Each year, over 500,000 patients require stents to treat atherosclerosis, a condition
where the blood vessels narrow due to the buildup of cholesterol along the artery
walls. Stents provide physical support to clear occluded blood vessels and are
currently among the most common treatments for patients with advanced stages of
atherosclerosis. However, several issues exist that limit the utility and widespread
application of stents. While bare metal stents (BMSs) provide mechanical support to
regain adequate circulatory flow, this treatment has been associated with long-term
restenosis, an inflammatory response leading to smooth muscle cell (SMC)
proliferation and vessel re-occlusion. This cascade begins days to weeks after
implantation, lasts for weeks to months, and occurs in as many as 60% of patients.
To combat this issue, drug-eluting stents (DESs) that release anti-proliferative drugs,
such as paclitaxel or sirolimus, were developed. Although these drugs effectively
reduce SMC proliferation, the cytotoxic or immunosuppressive inhibition mechanism
significantly delays the arterial healing process and often leads to blood clots that
re-occlude the vessel. As a result, mortality rates between bare metal stents and
DESs are similar, as restenosis issues in BMSs and DESs, respectively, increase the
likelihood of restricted blood flow, secondary surgeries, angina, myocardial
infarction, and death. As a result, there is a significant need for novel therapeutics
and medical devices which can reduce smooth muscle cell proliferation with low
cytotoxicity.
Sample Please provide a writing sample (approximately 250-350 words)
Damage to the peripheral nerves (PNs) may occur as a result of trauma, pathology,
surgery, cancer, or congenital defects and can often be severe. Misdirected
reinnervation can lead to life-long pain, functionally disabled muscle contraction and
coordination, and inappropriate reflexes.1 As a result, over 800,000 nerve injury
surgeries take place annually to help patients regain sensation and motor control.2
Autologous nerve grafting is the gold standard for repairing nerve gaps larger than
1 cm, although limitations include a shortage of donor tissue and donor site
morbidity.3 While PNs possess inherent ability to regenerate over short distances (<
3 cm), larger defects require a support matrix to promote reinnervation and align
regenerating nerves with the original muscle and sensory targets for return of
function.
Guidance conduits direct nerve regeneration so that the proximal and distal stumps
can converge to provide functional sensory and motor recovery. Biopolymeric and
synthetic nerve conduits are attractive alternatives to autografts, as they are
fabricated in a wide range of sizes with tailored properties to optimize and promote
the healing response. However, current conduits do not address the ability to repair
severe injuries over long distances, restrict fibrous tissue in-growth, and promote
diffusion of neurotropic and neurotrophic factors.1 Large injuries will invariably
traverse areas of flexing and bending, which require biodegradable conduits that
can withstand cyclic compression while maintaining an open lumen for axon growth
to prevent pinching of the regenerating nerve during bending and later degrade to
reduce the risk of compression. Fabrication of tubular grafts created from braided
synthetic polymer fibers can be produced to accommodate any length and can
provide high flexibility while withstanding compressive forces.
References
1. Brett Runge, M. et al. The development of electrically conductive
polycaprolactone fumarate–polypyrrole composite materials for nerve regeneration.
Biomaterials 31, 5916-5926 (2010).
2. Kehoe, S., Zhang, X. & Boyd, D. FDA approved guidance conduits and wraps for
peripheral nerve injury: A review of materials and efficacy. Injury 43, 553-572
(2012).
3. Johnson, E. O. & Soucacos, P. N. Nerve repair: experimental and clinical evaluation
of biodegradable artificial nerve guides. Injury 39, 30-36 (2008).
In addition to developing life-saving treatments while working at a major healthcare
company, I am staying current by pursuing a PhD in biomedical engineering.
Prompt Discuss one of the following in 200-300 words:
Discuss a medical condition, and some treatments for it (including herbal
supplements, and non drug treatments etc.)
Each year, over 500,000 patients require stents to treat atherosclerosis, a condition
where the blood vessels narrow due to the buildup of cholesterol along the artery
walls. Stents provide physical support to clear occluded blood vessels and are
currently among the most common treatments for patients with advanced stages of
atherosclerosis. However, several issues exist that limit the utility and widespread
application of stents. While bare metal stents (BMSs) provide mechanical support to
regain adequate circulatory flow, this treatment has been associated with long-term
restenosis, an inflammatory response leading to smooth muscle cell (SMC)
proliferation and vessel re-occlusion. This cascade begins days to weeks after
implantation, lasts for weeks to months, and occurs in as many as 60% of patients.
To combat this issue, drug-eluting stents (DESs) that release anti-proliferative drugs,
such as paclitaxel or sirolimus, were developed. Although these drugs effectively
reduce SMC proliferation, the cytotoxic or immunosuppressive inhibition mechanism
significantly delays the arterial healing process and often leads to blood clots that
re-occlude the vessel. As a result, mortality rates between bare metal stents and
DESs are similar, as restenosis issues in BMSs and DESs, respectively, increase the
likelihood of restricted blood flow, secondary surgeries, angina, myocardial
infarction, and death. As a result, there is a significant need for novel therapeutics
and medical devices which can reduce smooth muscle cell proliferation with low
cytotoxicity.
Sample Please provide a writing sample (approximately 250-350 words)
Damage to the peripheral nerves (PNs) may occur as a result of trauma, pathology,
surgery, cancer, or congenital defects and can often be severe. Misdirected
reinnervation can lead to life-long pain, functionally disabled muscle contraction and
coordination, and inappropriate reflexes.1 As a result, over 800,000 nerve injury
surgeries take place annually to help patients regain sensation and motor control.2
Autologous nerve grafting is the gold standard for repairing nerve gaps larger than
1 cm, although limitations include a shortage of donor tissue and donor site
morbidity.3 While PNs possess inherent ability to regenerate over short distances (<
3 cm), larger defects require a support matrix to promote reinnervation and align
regenerating nerves with the original muscle and sensory targets for return of
function.
Guidance conduits direct nerve regeneration so that the proximal and distal stumps
can converge to provide functional sensory and motor recovery. Biopolymeric and
synthetic nerve conduits are attractive alternatives to autografts, as they are
fabricated in a wide range of sizes with tailored properties to optimize and promote
the healing response. However, current conduits do not address the ability to repair
severe injuries over long distances, restrict fibrous tissue in-growth, and promote
diffusion of neurotropic and neurotrophic factors.1 Large injuries will invariably
traverse areas of flexing and bending, which require biodegradable conduits that
can withstand cyclic compression while maintaining an open lumen for axon growth
to prevent pinching of the regenerating nerve during bending and later degrade to
reduce the risk of compression. Fabrication of tubular grafts created from braided
synthetic polymer fibers can be produced to accommodate any length and can
provide high flexibility while withstanding compressive forces.
References
1. Brett Runge, M. et al. The development of electrically conductive
polycaprolactone fumarate–polypyrrole composite materials for nerve regeneration.
Biomaterials 31, 5916-5926 (2010).
2. Kehoe, S., Zhang, X. & Boyd, D. FDA approved guidance conduits and wraps for
peripheral nerve injury: A review of materials and efficacy. Injury 43, 553-572
(2012).
3. Johnson, E. O. & Soucacos, P. N. Nerve repair: experimental and clinical evaluation
of biodegradable artificial nerve guides. Injury 39, 30-36 (2008).
