Medical Specialties Commons^™

Brain Neprilysin Activity And Susceptibility To Transgene-Induced Alzheimer Amyloids, Troy L. Carter, Steve Pedrini, Jorge Ghiso, Michelle E. Ehrlich, Sam Gandy

Department of Neurology Faculty Papers

Neprilysin (NEP) is a zinc metalloproteinase that degrades enkephalins, endothelins, and the Alzheimer’s disease amyloid ß (Aß) peptides. NEP-deficient mice possess increased levels of brain Aß^1-40 and Aß^1-42. The objective of this study was to determine whether tissue NEP specific activity differs according to age and/or across mouse strains, especially those strains predisposed toward formation of Aß-amyloid plaques following overexpression of the human Alzheimer amyloid precursor protein (APP). The C57Bl/6J mouse strain appears to be relatively susceptible to cerebral amyloidosis, whereas the Swiss Webster (SW) strain appears more resistant. We investigated whether NEP specific activity in brain …

Prognostic Indicators In Patients With Primary Intraventricular Haemorrhage, Bilal Hameed, Bhojo A. Khealani, Tahseen Mozzafar, Mohammad Wasay

Department of Medicine

Objectives: Primary intraventricular haemorrhage (PIVH) is a rare clinical entity. We sought to evaluate risk factors, clinical and radiological features, and outcome of patients with PIVH.

Materials and Methods: Cases of PIVH were identified from cohort of patients with non traumatic intracerebral haemorrhage (ICH) by reviewing the radiological data. Their charts were reviewed and demographic, clinical, radiological and laboratory data was recorded and analyzed. Chi square and t test were used to determine predictors of poor outcome.

Results: Fifteen of 677 (2%) patients with ICH had PIVH. Nine (60%) were men. Median age was 56 years. Predisposing factors included hypertension …

Organization And Signal Processing Of The Descending Tracts In The Cervical Spinal Cord, Yanmei Tie

Doctoral Dissertations

This dissertation addresses the research for the development of spinal cord-computer interface (SCCI). The main objective of SCCI is to generate voluntary motor control signals for individuals with spinal cord injury (SCI).

In the neuroscience aspect, organization of the fibers in the descending tracts of the dorsolateral funiculus of the cervical spinal cord was investigated in cats. The spinal cord was penetrated with silicon substrate microelectrodes at 400 μm intervals in the medio-lateral direction at the C5/C6 and C6/C7 segmental borders. The stimulus consisted of a 20 ms train of charge-balanced biphasic pulses at 330 Hz. The evoked activities from …

Rapidly Developing Optic Neuritis Secondary To Ethambutol: Possible Mechanism Of Injury, Sajjad Ali, Uzma Usman, Mohammad Wasay

Department of Medicine

Optic neuritis has been described among the toxic effects of Ethambutol. This side effect is dose related. The mean duration of Ethambutol induced optic neuritis (EON) is three months. We report a case of EON after few days of exposure to Ethambutol and the symptoms resolved after discontinuation of Ethambutol. This most likely represents an idiosyncratic reaction which is different as compared to dose related optic neuritis.

The Cns Role Of Toll-Like Receptor 4 In Innate Neuroimmunity And Painful Neuropathy, Flobert Y. Tanga, Nancy Nutile-Mcmenemy, Joyce A. Deleo

Dartmouth Scholarship

Neuropathic pain remains a prevalent and persistent clinical problem because of our incomplete understanding of its pathogenesis. This study demonstrates for the first time, to our knowledge, a critical role for CNS innate immunity by means of microglial Toll-like receptor 4 (TLR4) in the induction phase of behavioral hypersensitivity in a mouse and rat model of neuropathy. We hypothesized that after L5 nerve transection, CNS neuroimmune activation and subsequent cytokine expression are triggered by the stimulation of microglial membrane-bound TLR4. To test this hypothesis, experiments were undertaken to assess tactile and thermal hypersensitivity in genetically altered (i.e., TLR4 knockout and …

The Effects Of Greater Occipital Nerve Block And Trigger Point Injection On Brush Allodynia And Pain In Migraine, Avi Ashkenazi, William B. Young

Department of Neurology Faculty Papers

Objective: To evaluate the effect of GONB, with or without trigger point injection (TPI), on dynamical mechanical (brush) allodynia (BA) and on head pain in migraine.

Background: Patients with migraine often have cutaneous allodynia, which is related to sensitization of central pain neurons. Greater occipital nerve block (GONB) is an effective treatment for migraine headache, however its effect on cutaneous allodynia in migraine is unknown.

Methods: We studied patients with migraine and BA who were treated with GONB with or without TPI. Demographic data, migraine history and headache features were documented. Allodynia was evaluated using a structured …

Gas-Producing Brain Abscess, Arshad A. Siddiqui, Khalid N. Chishti

Section of Neurosurgery

A case of a known psychiatric patient who presented with rapid neurological deterioration is reported. Neuroimaging revealed a gas-producing brain abscess in left parietal lobe with a contiguous focus of infection in the adjacent bone and scalp initiated by obsessive scalp scratching. On complete surgical excision of abscess, followed by culture-based antibiotic therapy, a good neurological recovery was achieved with minimal residual deficits at follow-up.

Involvement Of Beta-Chemokines In The Development Of Inflammatory Demyelination., Ileana Banisor, Thomas P Leist, Bernadette Kalman

Department of Neurology Faculty Papers

The importance of beta-chemokines (or CC chemokine ligands - CCL) in the development of inflammatory lesions in the central nervous system of patients with multiple sclerosis and rodents with experimental allergic encephalomyelitis is strongly supported by descriptive studies and experimental models. Our recent genetic scans in families identified haplotypes in the genes of CCL2, CCL3 and CCL11-CCL8-CCL13 which showed association with multiple sclerosis. Complementing the genetic associations, we also detected a distinct regional expression regulation for CCL2, CCL7 and CCL8 in correlation with chronic inflammation in multiple sclerosis brains. These observations are in consensus with previous studies, and add new …

Characterization Of The Zona Incerta, Heather Joyce Green

Theses and Dissertations

Parkinson's Disease affects more than 1 million people in the United States with 60,000 new cases being diagnosed each year. Currently, there is no cure for Parkinson's Disease, but there are several treatment options available. Currently the most popular surgical option is Deep Brain Stimulation. Microelectrode recording helps identify nuclei as the microelectrode passes through them. While the firing frequencies of the target nuclei are well defined, other nuclei are not. This study will attempt to characterize the Zona Incerta, which is the structure directly above the Subthalamic Nucleus, a target nucleus. Characterization of the firing frequency of the Zona …

Referred Cutaneous Allodynia In A Migraine Patient Without Simultaneous Headache, Avi Ashkenazi, Carla Lopinto, William B. Young

Department of Neurology Faculty Papers

Cutaneous allodynia is defined as the perception of pain when a non-noxious stimulus is applied to normal skin. This phenomenon has been demonstrated in migraine patients during an acute attack. It is thought to result from central sensitization of neurons in the trigemino-vascular system and may spread to areas beyond that of the referred head pain.

In a recent study, migraine patients demonstrated increased temporal summation to painful mechanical stimuli in their referred head pain area between attacks. This suggests that changes in physiologic properties of nociceptive neurons may occur in migraine patients between attacks.

We describe a migraine patient …

Epileptogenesis Causes Long-Term Plasticity Changes In Calbindin D-28k In The Rat Pilocarpine Model Of Acquired Epilepsy, Anne Johnston Harrison

Theses and Dissertations

Epilepsy is one of the most common neurological disorders, affecting more than 2% of children and 1% of adults in the U.S. Emerging research has demonstrated that calcium, as a major second messenger system, underlies many of these injury-induced plasticity changes associated with the development of epilepsy. Recent evidence has suggested that long term elevations in neuronal resting calcium levels play a role in initiating and maintaining epileptogenesis (the development of epilepsy). Collaborations between our lab and others have produced microarray data that suggests that a major calcium-binding protein, calbindin D-28k, mRNA levels are decreased in epileptic rats even up …

The Long Shadow Of Cerebral Localization, Saad Shafqat

Section of Neurology

In 1995, during my first week as a neurology resident at Massachusetts General Hospital, I had the privilege of meeting the late Raymond Adams. He was an established octogenarian by then, but the years had made no difference to his air of professionalism and academic authority. His reputation was made in the 1950s and 1960s, when he developed Boston as a major centre of clinical neurology. Among other things, he is immortalized through a famous textbook that has appeared in multiple editions. Our meeting took place at a clinical conference in which I was required to present a case. He …

Development Of A Comprehensive Epilepsy Surgery Programme In Pakistan, Mughis Sheerani

Section of Neurology

No abstract provided.

Childhood Traumatic Brain Injury: Recovery Of Working Memory Function And Behavioral Adjustment, Gayle L. Crahen

All-Inclusive List of Electronic Theses and Dissertations

Children and adolescents with a traumatic brain injury (TBI) were the focus of this investigation using an extant data set. The 3 7 participants were between the ages of 5 and 15 years at the time of injury, and the majority had a severe TBI. Participants were evaluated soon after injury for a Baseline description of functioning on measures of cognition and memory and re-evaluated at one and/or two year return appointments. Parents provided estimates of adaptive, internalizing, and externalizing behaviors at Baseline and at follow-up appointments on the V ABS and CBCL. It was expected that parents' descriptions of …

Preventing Neural Tube Defects By Folic Acid Fortification Of Flour, Rashid Jooma

Section of Neurosurgery

No abstract provided.

Dynamic Mechanical (Brush) Allodynia In Cluster Headache, Avi Ashkenazi, William B. Young

Department of Neurology Faculty Papers

Cutaneous allodynia is the perception of pain when a non-noxious stimulus is applied to normal skin. It has been described in patients with migraine. Cutaneous allodynia is caused by sensitization of central nervous system neurons that receive convergent sensory input from both skin and intracranial structures. This phenomenon has not been previously described in patients with cluster headache. Although migraine and cluster headache (CH) may share some clinical features, the pathogenesis of these two primary headaches is different. The aim of this study was to examine the occurrence of dynamic mechanical (brush) allodynia (BA) in patients with CH.

Periodic Autonomic Dysfunction Without Pain In A Patient With Cluster Headache, Avi Ashkenazi, Stephen Silberstein

Department of Neurology Faculty Papers

Cluster headache (CH) is characterized by episodes of severe unilateral headache accompanied by symptoms of cranial parasympathetic hyperactivity and sympathetic dysfunction that occur in cluster periods. Positron emission tomography (PET) studies have demonstrated evidence of a central generator of CH attacks located in the posterior-inferior hypothalamus. It has been suggested that the autonomic symptoms in CH result from reflex activation of the superior salivatory nucleus secondary to activation of the trigeminal nucleus caudalis (TNC). However, several cases of CH-like symptoms with no head pain have been documented.

We describe a patient who had suffered from typical episodic CH for two …

Patterns Of Tuberculosis In The Central Nervous System, Soobia Raza, Aliyah Sadaf, Faisal Fecto, Rushna Pervez Ali, Muhammad Ehsan Bari, Ather Enam

Medical College Documents

Tuberculous involvement of central nervous system (CNS), although not very frequent, results in severe morbidity. Tuberculosis (TB) is endemic in developing countries but even in developed countries, after an initial decline up until 1980’s, incidence of TB is on the rise. The AIDS epidemic, emergence of multi-drug resistant strains and immigration of people from endemic areas are some of the factors significantly contributing to this increase. Consequently, the burden of central nervous system tuberculosis has increased significantly worldwide.

Occipital Nerve Block Rapidly Eliminates Allodynia Far From The Site Of Headache: A Case Report, William B. Young, Valentin Mateos, Avi Ashkenazi

Department of Neurology Faculty Papers

Seventy to 80% of persons with migraine develop allodynia during the course of a severe attack. During a migraine attack, allodynia spreads topographically to extratrigeminal territory. Dynamic mechanical allodynia, otherwise known as brush allodynia (BA), is a subtype of allodynia that is easily tested. Ashkenazi & Young recently reported on the immediate benefits of greater occipital nerve (GON) block on brush allodynia and pain in migraine and in cluster headache. In these studies, testing was performed at fixed sites in the trigeminal and cervical distributions. Allodynia in thoracic dermatomes was not studied.

Headache Management For The Pain Specialist, Avi Ashkenazi, Stephen Silberstein

Department of Neurology Faculty Papers

Headache is a common symptom caused by a wide variety of diseases. Primary headaches include migraine, cluster headache, tension-type headache and other less common diseases. It is important to differentiate these headaches from secondary headaches caused by vascular, neoplastic, infectious, metabolic and toxic disorders. Most primary headaches have a genetic basis, with environmental factors acting as triggers. Recent advances in basic research resulted in the development of more specific and effective therapies. Medication overuse headache is a very common cause of chronic daily headache. Detoxification from the offending drug is essential for headache improvement. Cervicogenic headache is common and needs …

Similar Promotion Of Abeta1-42 Fibrillogenesis By Native Apolipoprotein E Epsilon3 And Epsilon4 Isoforms., David Sweeney, Ralph Martins, Harry Levine, Jonathan D Smith, Sam Gandy

Farber Institute for Neuroscience Faculty Papers

The apolipoprotein E epsilon4 allele contributes to the genetic susceptibility underlying a large proportion (~40-60%) of typical, sporadic Alzheimer disease. Apolipoprotein E deficient mice made transgenic for human apolipoprotein E epsilon4 accumulate excess cerebral amyloid when compared to similarly prepared mice expressing human apolipoprotein E epsilon3. Therefore, it is important to search for relevant interactions(s) between apolipoprotein E epsilon4 and Abeta in order to clarify the biological role for apolipoprotein E epsilon4 in Alzheimer disease. Using a thioflavine T (ThT)-based assay, we have investigated the effects of native human apolipoprotein E isoforms on the kinetics of Abeta fibrillogenesis. No obvious …

The Ultrastructure Of The Olfactory System In Two Species Of Short-Tailed Shrews, Blarina Brevicauda And Blarina Carolinensis, Lisa Johnson Byrum

Theses and Dissertations in Biomedical Sciences

Several studies of the fine structure of the olfactory system of rodents have been conducted, but very little research has been done on members of the Insectivora. The olfactory systems of the northern short-tailed shrew, Blarina brevicauda, and the southern short-tailed shrew, Blarina carolinensis, were examined by light and electron microscopy. These shrews were live trapped in the vicinity of Norfolk, Virginia throughout all months of the year. Olfactory tissues were processed following standard transmission and scanning electron microscopy protocols. The olfactory system structures investigated included the olfactory epitheliumlmucosa (OEM), main olfactory bulb (MOB), accessory olfactory bulb (AOB), …

Chance-Type Flexion-Distraction Fracture Of Lumbar Spine, Arshad A. Siddiqui, Ahmad Ali Shah

Section of Neurosurgery

A case of a twenty years old male who had been hit by a van at the lower back, presented two weeks later with complete paraplegia and double incontinence is presented. Radiological imaging revealed shearing of spine with fracture line slicing through the second lumbar (L2) vertebra going across all the three vertebral columns with complete retrolisthesis of upper fragment. He was managed conservatively with immobilization and rehabilitation.

Neurology In The 21st Century: Contemporary State Of Diagnostics And Therapeutics, Saad Shafqat, Mohammad Wasay

Department of Medicine

Although neurological disease has been recognized since antiquity, neurology as a systematic clinical discipline is less than 130 years old. Neurological practice has traditionally been constrained by the complexity of the human nervous system, which has been slow to yield its secrets. Over the last three decades, however, clinical neurology has been transformed in terms of both diagnostics and therapeutics and now marches in lockstep with the cutting edge of medicine. Efficacious treatments are now available for the majority of neurological diseases, including epilepsy, migraine, Guillain-Barre syndrome, Parkinson's disease, multiple sclerosis, and ischemic stroke. This neurological revolution has been enabled …

Neural Correlates Of Art Therapy As Indicated Through Electroencephalography, Kerry A. Kruk

EVMS School of Health Professions Theses & Dissertations

Quantitative electroencephalograph (QEEG) reports of 14 healthy women participants engaged in art making in response to two general art therapy directives were generated and compared at Eastern Virginia Medical School. A Cadwell Easy-II 32-channel digital EEG and Physiometrx E-net which contains placements according to the International 10-20 system were used to collect brainwave activity. This study explored the effects of clay sculpting and marker drawing conditions on neural activity in the right and left frontal and parietal cortices.

One aim of the study was to illuminate what Lusebrink (1990) suggested - that different types of media and processes elicit different …

Complete Surgical Excision Of Intramedullary Schwannoma At The Craniovertebral Junction In Neurofibromatosis Type-2, A A. Siddiqui, A A. Shah

Section of Neurosurgery

Intramedullary spinal schwannomas are extremely rare. We describe a case of a 13-year-old female who was found to have an intramedullary schwannoma at craniovertebral junction along with incidental bilateral acoustic neuromas, which was excised completely. To our knowledge, this is the first report of a case of intramedullary schwannoma in association with NF-2 located at the craniovertebral junction. The literature has been reviewed with emphasis on radiological imaging, histopathological diagnosis and technique to achieve complete microsurgical excision.

An Audit Of Head Trauma Care And Mortality, Arshad A. Siddiqui, Hasnain Zafar, S H. Bashir

Section of Neurosurgery

Objective: To analyze the factors contributing to deaths from head trauma by using standardized assessment parameters and to provide a peer-review of head injury deaths with focus on identifying deficiencies and analyzing contributory factors.
Design: Descriptive study.
Place and duration of study: The study was carried out at the Emergency, Aga Khan University Hospital during January 1998 to December 1999.
Subjects and method: One hundred and three patients above the age of 15 years presenting alive to the Aga Khan University Hospital (AKUH) emergency with head injury were included in this study. Identified deaths data was reviewed by the Hospital …

Motor Neuronopathy Associated With Adenocarcinoma Of Esophagus, Bhojo A Khealani, R. Qureshi, Mohammad Wasay

Department of Medicine

Neurologic paraneoplastic syndromes (NPS) are remote neurologic effects, except metastasis, of systemic cancers. These are a rare group of disorders, commonly associated with small cell lung carcinoma (SCLC).1 Various NPS have been described, including motor neuronopathy. The motor neuronopathy has commonly been described with small cell carcinoma of lung, breast cancer and lymphoproliferative disorders.2,3 We report a case of motor neuronopathy in association with large cell adenocarcinoma of esophagus. To our knowledge this is the first reported case of motor neuronopathy associated with adenocarcinoma of the esophagus.

Prognostic Indicators In Patients With Intracranial Tuberculoma: A Review Of 102 Cases, Mohammad Wasay, M. K. Moolani, J. Zaheer, Bhojo A. Khealani, R. A. Smego, A. R. Sarwari

Department of Medicine

Objective:

To see the characteristics, course and outcome of patients suffering from intracranial tuberculoma.

Methods:

Retrospective review of 102 patients diagnosed as intracranial tuberculoma at a tertiary care center over 10 years.

Results:

A total of 102 cases were seen with an age range of 1 to 75 years (mean, 30 years). Predisposing factors included Diabetes mellitus (8 patients) and pregnancy or puerperium (7 patients). Five pediatric patients had tuberculoma despite documented BCG vaccination. Fever (59%), headache (57%), meningeal irritation (36%) were the commonest presenting features; one-third of patients were drowsy or comatosed at presentation. Cerebrospinal fluid analysis was performed …

Botulinum Toxin And Other New Approaches To Migraine Therapy, Avi Ashkenazi, Stephen Silberstein

Department of Neurology Faculty Papers

The number of migraine treatments and our understanding of migraine pathophysiology are both increasing. Newer treatments are focusing on migraine prevention. Botulinum toxin (BTX) is a potent neurotoxin that has been used primarily for diseases associated with increased muscle activity. Recently the toxin was found to have antinociceptive effects that are probably independent of its muscle-relaxant action. Recent clinical trials support the efficacy of BTX type-A (and possibly also type-B) in the treatment of migraine. The anticonvulsant topiramate was recently shown to be effective for migraine prevention. With the low doses used for this indication, cognitive side effects are less …