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1.
J Natl Med Assoc ; 112(1): 36-43, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31980210

ABSTRACT

BACKGROUND/PURPOSE: With the urgency to create more equitable health care, increased research and early exposure to health interventions and clinical medicine are imperative. Health disparities continue to persist nationwide, particularly in underserved areas and among traditionally disadvantaged populations. In addition to the need to eliminate health disparities, increasing the diversity among health professionals to more accurately reflect the US population is essential. METHODS: The health professions partnership at the School of Medicine and the School of Dental Medicine is a comprehensive pipeline designed to increase the preparation of underrepresented students for health careers. Through this health professions pipeline's Health Disparities Clinical Summer Research Fellowship Program (HDCSRFP), undergraduate students are exposed to health disparities research and clinical skills over seven weeks. Over the course of the program, participants conducted a research project, gained clinical exposure by shadowing community physicians and other health professionals, and received mentoring by health professional faculty and students. At the conclusion of the program, participants presented their research projects during a poster symposium. RESULTS: A total of 121 program participants between 2008 and 2018 each conducted a research project focused on reducing health inequities within specific populations, particularly in urban settings. The health professions pipeline has been instrumental in increasing the aptitude and competitiveness of these students pursuing health careers through participation in research, clinical medicine, and enrichment activities. Specifically, 92% of the 79 program participants identified who completed undergraduate studies before the end of the 2018 fall semester pursued a career or further studies within a health profession. Forty-six percent of these college graduates were accepted or matriculated in medical school by the end of 2018. CONCLUSION: The HDCSRFP, like the other health professions partnership pipeline programs, serves as a model for other educational programs to expose students to the field of medicine and health research, and to increase diversity within health professions.


Subject(s)
Career Choice , Clinical Medicine/education , Education, Medical, Undergraduate/methods , Health Occupations , Minority Groups , Health Services Research/methods , Humans , Minority Groups/education , Minority Groups/statistics & numerical data , Program Evaluation , Schools, Medical/organization & administration , Students, Public Health/statistics & numerical data
2.
J Racial Ethn Health Disparities ; 6(1): 207-213, 2019 02.
Article in English | MEDLINE | ID: mdl-30014447

ABSTRACT

The Department of Health Career Opportunity Programs at UConn Health has developed the Aetna Health Professions Partnership Initiative (Aetna HPPI), a formal education consortium offering a comprehensive program of educational enrichment and support activities for underrepresented and first-generation students. The purpose is to identify and develop a diverse applicant pool of students who will eventually enter a health professions career with a focus on medicine and dental medicine. Activities are conducted for students in middle school through college. The achievements of the middle and high school pipeline programs and their impact on producing a more diversified health professions workforce were examined. The students are recruited from the greater Hartford, CT area and come from backgrounds traditionally underrepresented in healthcare, first-generation college families and modest family means. Program elements include a 30-week academic year Saturday Academy and a 6-week summer academic enrichment program aimed at preparing students for successful entrance into college, and a Parental Seminar Series for parents. Some of the activities include science, math, language arts, PSAT, SAT and ACT preparation, college tours, career counseling, mentoring by health professionals, and cultural experiences. Data analysis and tracking of the students in the academy have revealed some significant achievements. All seniors in the academy have graduated from high school. The SAT scores of the academy students have consistently stood above the average for the rest of the Hartford School District. In addition, the graduating seniors have a high rate of college matriculation.


Subject(s)
Health Occupations , Minority Groups/psychology , Personnel Selection/organization & administration , Schools , Students/psychology , Career Choice , Connecticut , Humans , Minority Groups/statistics & numerical data , Schools/statistics & numerical data , Students/statistics & numerical data
3.
Burns ; 40(8): 1748-53, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24767716

ABSTRACT

PURPOSE: Burns remain disproportionately prevalent in developing countries. This study aims to describe the epidemiology of burns in Sierra Leone to serve as a baseline for future programs. METHODS: A cluster randomized, cross-sectional, countrywide survey was conducted in 2012 in Sierra Leone. With a standardized questionnaire demographics and deaths during the previous 12 months of household members were assessed with the household representative. Thereafter, 2 randomly selected household members were interviewed, elucidating whether participants had ever had a burn in six body regions and determining burn mechanisms and patterns of health care seeking behavior. RESULTS: This study included 1843 households and 3645 individuals. 3.98% (145/3645) of individuals reported at least one burn-injury. The highest proportions of burns were reported in the age groups 0-4 years old (23/426, 5.4%) and 5-14 years old (37/887, 4.17%). The majority of burns (129/145, 89.0%) were caused by a hot liquid/object and the upper, extremities were the most commonly burned body regions, with 36% (53/145) of cases. 21% (30/145) of individuals with burns sought care from a traditional healer. CONCLUSIONS: Burns are highly prevalent in Sierra Leone. Further research and resources should be allocated to the care and prevention of thermal injuries.


Subject(s)
Burns/epidemiology , Adolescent , Adult , Burns/etiology , Child , Child, Preschool , Cluster Analysis , Cross-Sectional Studies , Female , Humans , Infant , Male , Middle Aged , Patient Acceptance of Health Care , Prevalence , Sierra Leone/epidemiology , Surveys and Questionnaires , Young Adult
4.
J Mol Biol ; 426(9): 1995-2008, 2014 May 01.
Article in English | MEDLINE | ID: mdl-24530795

ABSTRACT

Spore germination in Bacillus species represents an excellent model system with which to study the molecular mechanisms underlying the nutritional control of growth and development. Binding of specific chemical nutrients to their cognate receptors located in the spore inner membrane triggers the germination process that leads to a resumption of metabolism in spore outgrowth. Recent studies suggest that the inner membrane GerD lipoprotein plays a critical role in the receptor-mediated activation of downstream germination events. The 121-residue core polypeptide of GerD (GerD6°â»¹8°) from Geobacillus stearothermophilus forms a stable α-helical trimer in aqueous solution. The 2.3-Å-resolution crystal structure of the trimer reveals a neatly twisted superhelical rope, with unusual supercoiling induced by parallel triple-helix interactions. The overall geometry comprises three interleaved hydrophobic screws of interacting helices linked by short turns that have not been seen before. Using complementation analysis in a series of Bacillus subtilis gerD mutants, we demonstrated that alterations in the GerD trimer structure have profound effects on nutrient germination. This important structure-function relationship of trimeric GerD is supported by our identification of a dominant negative gerD mutation in B. subtilis. These results and those of others lead us to propose that GerD mediates clustering of germination proteins in the inner membrane of dormant spores and thus promotes the rapid and cooperative germination response to nutrients.


Subject(s)
Bacillus subtilis/growth & development , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Geobacillus stearothermophilus/growth & development , Spores, Bacterial/growth & development , Amino Acid Sequence , Bacillus subtilis/chemistry , Bacillus subtilis/genetics , Bacillus subtilis/metabolism , Bacterial Proteins/genetics , Crystallography, X-Ray , DNA Mutational Analysis , Genetic Complementation Test , Geobacillus stearothermophilus/chemistry , Geobacillus stearothermophilus/genetics , Geobacillus stearothermophilus/metabolism , Lipoproteins/chemistry , Lipoproteins/genetics , Lipoproteins/metabolism , Membrane Proteins/chemistry , Membrane Proteins/genetics , Membrane Proteins/metabolism , Models, Molecular , Molecular Sequence Data , Protein Conformation , Protein Multimerization , Sequence Alignment , Spores, Bacterial/chemistry , Spores, Bacterial/genetics , Spores, Bacterial/metabolism
5.
J Bacteriol ; 195(16): 3575-82, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23749970

ABSTRACT

Germination of dormant Bacillus subtilis spores with specific nutrient germinants is dependent on a number of inner membrane (IM) proteins, including (i) the GerA, GerB, and GerK germinant receptors (GRs) that respond to nutrient germinants; (ii) the GerD protein, essential for optimal GR function; and (iii) SpoVA proteins, essential for the release of the spore-specific molecule dipicolinic acid (DPA) during spore germination. Levels of GR A and C subunit proteins, GerD, and SpoVAD in wild-type spores were determined by Western blot analysis of spore fractions or total disrupted spores by comparison with known amounts of purified proteins. Surprisingly, after disruption of decoated B. subtilis spores with lysozyme and fractionation, ∼90% of IM fatty acids and GR subunits remained with the spores' insoluble integument fraction, indicating that yields of purified IM are low. The total lysate from disrupted wild-type spores contained ∼2,500 total GRs/spore: GerAA and GerAC subunits each at ∼1,100 molecules/spore and GerBC and GerKA subunits each at ∼700 molecules/spore. Levels of the GerBA subunit determined previously were also predicted to be ∼700 molecules/spore. These results indicate that the A/C subunit stoichiometry in GRs is most likely 1:1, with GerA being the most abundant GR. GerD and SpoVAD levels were ∼3,500 and ∼6,500 molecules/spore, respectively. These values will be helpful in formulating mathematic models of spore germination kinetics as well as setting lower limits on the size of the GR-GerD complex in the spores' IM, termed the germinosome.


Subject(s)
Bacillus subtilis/metabolism , Gene Expression Regulation, Bacterial/physiology , Spores, Bacterial/physiology , Bacillus subtilis/genetics , Fatty Acids/chemistry , Fatty Acids/metabolism , Mutation , Protein Subunits , Spores, Bacterial/chemistry
6.
JAMA Surg ; 148(5): 463-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23325317

ABSTRACT

OBJECTIVE: To use a nationwide household survey tool to provide an estimate of injury prevalence, mechanisms of traumatic injuries, and number of injury-related deaths in a low-income country. DESIGN: A randomized, cross-sectional nationwide survey using the Surgeons OverSeas Assessment of Surgical Need tool was conducted in 2012. SETTING: Sierra Leone, Africa. PARTICIPANTS: Three thousand seven hundred fifty randomly selected participants throughout Sierra Leone. MAIN OUTCOME MEASURES: Mechanisms of injury based on age, sex, anatomic location, cause, and sociodemographic factors as well as mechanisms of injury-related deaths in the previous year were the primary outcome measures. RESULTS: Data were collected and analyzed from 1843 households and 3645 respondents (98% response rate). Four hundred fifty-two respondents (12%) reported at least 1 traumatic injury in the preceding year. Falls were the most common cause of nonfatal injuries (40%). The extremities were the most common injury site regardless of age or sex. Traffic injuries were the leading cause of injury-related deaths (32% of fatal injuries). CONCLUSIONS: This study provides baseline data on the mechanisms of traumatic injuries as well as the sociodemographic factors affecting injury prevalence in one of the world's poorest nations. It is anticipated that these data will provide an impetus for further studies to determine injury severity, associated disability, and barriers to accessing care in these resource-poor areas.


Subject(s)
Accidents/statistics & numerical data , Developing Countries , Wounds and Injuries/epidemiology , Adolescent , Adult , Age Distribution , Aged , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Middle Aged , Needs Assessment , Sierra Leone/epidemiology , Socioeconomic Factors , Wounds and Injuries/pathology , Wounds and Injuries/therapy , Young Adult
7.
Lancet ; 380(9847): 1082-7, 2012 Sep 22.
Article in English | MEDLINE | ID: mdl-22898076

ABSTRACT

BACKGROUND: Surgical care is increasingly recognised as an important part of global health yet data for the burden of surgical disease are scarce. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) was developed to measure the prevalence of surgical conditions and surgically treatable deaths in low-income and middle-income countries. We administered this survey countrywide in Sierra Leone, which ranks 180 of the 187 nations on the UN Development Index. METHODS: The study was done between Jan 9 and Feb 3, 2012. 75 of 9671 enumeration areas, the smallest administrative units in Sierra Leone, were randomly selected for the study clusters, with a probability proportional to the population size. In each cluster 25 households were randomly selected to take part in the survey. Data were collected via handheld tablets by trained local medical and nursing students. A household representative was interviewed to establish the number of household members (defined as those who ate from the same pot and slept in the same structure the night before the interview), identify deaths in the household during the previous year, and establish whether any of the deceased household members had a condition needing surgery in the week before death. Two randomly selected household members underwent a head-to-toe verbal examination and need for surgical care was recorded on the basis of the response to whether they had a condition that they believed needed surgical assessment or care. FINDINGS: Of the 1875 targeted households, data were analysed for 1843 (98%). 896 of 3645 (25%; 95% CI 22·9-26·2) respondents reported a surgical condition needing attention and 179 of 709 (25%; 95% CI 22·5-27·9) deaths of household members in the previous year might have been averted by timely surgical care. INTERPRETATION: Our results show a large unmet need for surgical consultations in Sierra Leone and provide a baseline against which future surgical programmes can be measured. Additional surveys in other low-income and middle-income countries are needed to document and confirm what seems to be a neglected component of global health. FUNDING: Surgeons OverSeas, Thompson Family Foundation.


Subject(s)
Developing Countries , Health Services Needs and Demand/statistics & numerical data , Surgical Procedures, Operative/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cross-Sectional Studies , Female , Health Care Surveys , Health Services Research/methods , Humans , Infant , Male , Middle Aged , Needs Assessment , Random Allocation , Sierra Leone , Surgical Procedures, Operative/standards
8.
J Bacteriol ; 194(12): 3156-64, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22493018

ABSTRACT

Deletion of Bacillus subtilis spores' GerA germinant receptor (GR) had no effect on spore germination via the GerB plus GerK GRs, and loss of GerB plus GerK did not affect germination via GerA. Loss of one or two GRs also did not affect levels of GRs that were not deleted. Overexpression of GRs 5- to 18-fold increased rates of germination via the overexpressed GR and slowed germination by other GRs up to 15-fold. However, overexpression of one or two GRs had no effect on levels of GRs that were not overexpressed. These results suggest that either interaction between different GRs reduces the activity of GRs in triggering spore germination or all GRs compete for interaction with a limiting amount of a downstream signaling molecule in the germination pathway. Overexpression or deletion of GRs also had no effect on spores' levels of the GerD protein needed for normal GR-dependent germination or of the SpoVAD protein likely involved in dipicolinic acid release early in germination. Loss of GerD also had no effect on levels of GRs or SpoVAD. Spores of a strain lacking the only B. subtilis prelipoprotein diacylglycerol transferase, GerF, also had no detectable GerD or the GerA's C subunit, both of which are most likely lipoproteins; GerA's A subunit was also absent. However, levels of GerB's C subunit, also almost certainly a lipoprotein, and GerK's A subunit were normal in gerF spores. These results with gerF spores were consistent with effects of loss of GerF on spore germination by different GRs.


Subject(s)
Bacillus subtilis/growth & development , Gene Expression Regulation, Bacterial , Proteins/metabolism , Spores, Bacterial/growth & development , Gene Deletion , Gene Expression , Proteins/genetics
9.
J Bacteriol ; 194(13): 3417-25, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22522895

ABSTRACT

Bacillus subtilis isolates lacking the SpoVT protein, which regulates gene expression in developing forespores, gave spores that released their dipicolinic acid (DPA) via germinant receptor (GR)-dependent germination more rapidly than wild-type spores. Non-GR-dependent germination via dodecylamine was more rapid with spoVT spores, but germination via Ca-DPA was slower. The effects of a spoVT mutation on spore germination were seen with spores made in rich and poor media, and levels of SpoVT-LacZ were elevated 2-fold in poor-medium spores; however, elevated SpoVT levels were not the only cause of the slower GR-dependent germination of poor-medium spores. The spoVT spores had ≥5-fold higher GerA GR levels, ∼2-fold elevated GerB GR levels, wild-type levels of a GerK GR subunit and the GerD protein required for normal GR-dependent germination, ∼2.5-fold lower levels of the SpoVAD protein involved in DPA release in spore germination, and 30% lower levels of DNA protective α/ß-type small, acid-soluble spore proteins. With one exception, the effects on protein levels in spoVT spores are consistent with the effects of SpoVT on forespore transcription. The spoVT spores were also more sensitive to UV radiation and outgrew slowly. While spoVT spores' elevated GR levels were consistent with their more rapid GR-dependent germination, detailed analysis of the results suggested that there is another gene product crucial for GR-dependent spore germination that is upregulated in the absence of SpoVT. Overall, these results indicate that SpoVT levels during spore formation have a major impact on the germination and the resistance of the resultant spores.


Subject(s)
Bacillus subtilis/physiology , Bacterial Proteins/metabolism , Gene Expression Regulation, Bacterial , Membrane Proteins/metabolism , Amines/metabolism , Bacillus subtilis/genetics , Bacillus subtilis/growth & development , Bacillus subtilis/metabolism , Bacterial Proteins/genetics , Culture Media , Membrane Proteins/genetics , Microbial Viability , Picolinic Acids/metabolism , Spores, Bacterial/physiology
10.
J Neurovirol ; 18(1): 30-44, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22328242

ABSTRACT

Viral infections of the central nervous system (CNS) are associated with an increased risk for seizures during the acute infection period and the subsequent development of chronic epilepsy that is often difficult to treat. In previous work, we have shown that mice of the C57BL/6 strain infected with Theiler's murine encephalomyelitis virus (TMEV) exhibit a similar sequence, thereby providing a potential useful model of virus-induced epilepsy. The present study examines spontaneous and miniature excitatory postsynaptic currents in CA3 pyramidal cells recorded from brain slices prepared during both the acute phase during encephalitis and 2 months following TMEV infection. Animals that develop chronic epilepsy following TMEV infection exhibit considerable hippocampal sclerosis, directly implicating this brain region in the process of epileptogenesis. There are significant increases in amplitude and frequency of spontaneous and miniature excitatory currents in CA3 cells recorded in brain slices prepared during the acute infection period and 2 months after infection. However, the patterns of changes observed are markedly different during these two periods, suggesting that there are underlying changes in the network over time. These differences have implications for the treatment used during the acute infection and after chronic seizures develop.


Subject(s)
CA3 Region, Hippocampal/physiopathology , Encephalitis/physiopathology , Epilepsy/physiopathology , Seizures/physiopathology , Theilovirus , Acute Disease , Animals , CA3 Region, Hippocampal/virology , Chronic Disease , Disease Models, Animal , Encephalitis/complications , Encephalitis/virology , Epilepsy/complications , Epilepsy/virology , Excitatory Postsynaptic Potentials , Male , Mice , Mice, Inbred C57BL , Seizures/complications , Seizures/virology , Time Factors
11.
J Bacteriol ; 193(16): 4143-52, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21685283

ABSTRACT

Highly conserved amino acid residues in the C subunits of the germinant receptors (GRs) of spores of Bacillus and Clostridium species have been identified by amino acid sequence comparisons, as well as structural predictions based on the high-resolution structure recently determined for the C subunit of the Bacillus subtilis GerB GR (GerBC). Single and multiple alanine substitutions were made in these conserved residues in three regions of GerBC, and the effects of these changes on B. subtilis spore germination via the GerB GR alone or in concert with the GerK GR, as well as on germination via the GerA GR, were determined. In addition, levels of the GerBC variants in the spore inner membrane were measured, and a number of the GerBC proteins were expressed and purified and their solubility and aggregation status were assessed. This work has done the following: (i) identified a number of conserved amino acids that are crucial for GerBC function in spore germination via the GerB GR and that do not alter spores' levels of these GerBC variants; (ii) identified other conserved GerBC amino acid essential for the proper folding of the protein and/or for assembly of GerBC in the spore inner membrane; (iii) shown that some alanine substitutions in GerBC significantly decrease the GerA GR's responsiveness to its germinant l-valine, consistent with there being some type of interaction between GerA and GerB GR subunits in spores; and (iv) found no alanine substitutions that specifically affect interaction between the GerB and GerK GRs.


Subject(s)
Amino Acid Substitution/genetics , Bacillus subtilis/metabolism , Bacterial Proteins/metabolism , Gene Expression Regulation, Bacterial/physiology , Membrane Proteins/metabolism , Protein Subunits/metabolism , Amino Acid Substitution/physiology , Bacillus subtilis/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Kinetics , Membrane Proteins/genetics , Models, Molecular , Mutation , Protein Conformation , Protein Subunits/chemistry , Protein Subunits/genetics , Spores, Bacterial/genetics , Spores, Bacterial/metabolism
12.
Epilepsia ; 52(3): 589-601, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21275977

ABSTRACT

PURPOSE: Given the high incidence of refractory epilepsy, novel therapeutic approaches and concepts are urgently needed. To date, viral-mediated delivery and endogenous expression of antisense sequences as a strategy to prevent seizures have received little attention in epilepsy therapy development efforts. Here we validate adenosine kinase (ADK), the astrocyte-based key negative regulator of the brain's endogenous anticonvulsant adenosine, as a potential therapeutic target for antisense-mediated seizure suppression. METHODS: We developed adenoassociated virus 8 (AAV8)-based gene therapy vectors to selectively modulate ADK expression in astrocytes. Cell type selectivity was achieved by expressing an Adk-cDNA in sense or antisense orientation under the control of an astrocyte-specific gfaABC1D promoter. Viral vectors where injected into the CA3 of wild-type mice or spontaneously epileptic Adk-tg transgenic mice that overexpress ADK in brain. After virus injection, ADK expression was assessed histologically and biochemically. In addition, intracranial electroencephalography (EEG) recordings were obtained. KEY FINDINGS: We demonstrate in wild-type mice that viral overexpression of ADK within astrocytes is sufficient to trigger spontaneous recurrent seizures in the absence of any other epileptogenic event, whereas ADK downregulation via AAV8-mediated RNA interference almost completely abolished spontaneous recurrent seizures in Adk-tg mice. SIGNIFICANCE: Our data demonstrate that modulation of astrocytic ADK expression can trigger or prevent seizures, respectively. This is the first study to use an antisense approach to validate ADK as a rational therapeutic target for the treatment of epilepsy and suggests that gene therapies based on the knock down of ADK might be a feasible approach to control seizures in refractory epilepsy.


Subject(s)
Adenosine Kinase/genetics , Anticonvulsants/pharmacology , DNA, Antisense/pharmacology , Epilepsy/genetics , Epilepsy/therapy , Genetic Therapy , Animals , Astrocytes/physiology , DNA, Antisense/genetics , DNA, Complementary/genetics , Electroencephalography , Gene Knockdown Techniques , Genetic Vectors , Glial Fibrillary Acidic Protein/genetics , HEK293 Cells , Humans , Mice , Mice, Transgenic , Promoter Regions, Genetic/genetics , Signal Processing, Computer-Assisted
13.
J Neuropathol Exp Neurol ; 69(12): 1210-9, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21107134

ABSTRACT

Viral infection of the central nervous system can lead to long-term neurologic defects, including increased risk for the development of epilepsy. We describe the development of the first mouse model of viral-induced epilepsy after intracerebral infection with Theiler's murine encephalomyelitis virus. Mice were monitored with long-term video-electroencephalogram at multiple time points after infection. Most mice exhibited short-term symptomatic seizures within 3 to 7 days of infection. This was followed by a distinct latent period in which no seizures were observed. Prolonged video-electroencephalogram recordings at 2, 4, and 7 months after the initial infection revealed that a significant proportion of the mice developed profound, spontaneous epileptic seizures. Neuropathologic examination revealed hippocampal sclerosis in animals with epilepsy. Theiler's murine encephalomyelitis virus-infected C57BL/6 mice represent a novel "hit-and-run" model to investigate mechanisms underlying viral-induced short-term symptomatic seizures, epileptogenesis, and epilepsy. Importantly, this model will also be useful to investigate novel therapies for the treatment and prevention of epilepsy.


Subject(s)
Disease Models, Animal , Encephalomyelitis/complications , Encephalomyelitis/virology , Epilepsy/etiology , Epilepsy/virology , Theilovirus , Animals , Cell Line , Cricetinae , Male , Mice , Mice, Inbred C57BL
14.
Epilepsia ; 51(8): 1418-28, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20002148

ABSTRACT

PURPOSE: Central nervous system infections greatly increase the risk for the development of seizures and epilepsy (recurrent unprovoked seizures). We have previously shown that Theiler's murine encephalomyelitis virus (Theiler's virus or TMEV) infection causes acute symptomatic seizures in C57BL/6 (B6) mice. The objective of the present study was threefold: (1) to assess pathologic changes associated with acute TMEV infection and infection-induced seizures, (2) to determine whether Theiler's virus infection and associated acute seizures lead to chronically altered seizure susceptibility, and (3) to determine whether genetic background influences seizure susceptibility following Theiler's virus infection. METHODS: Immunohistochemical techniques were used to assess Theiler's virus antigen localization in the brain and associated neuronal cell death. A battery of electroconvulsive threshold (ECT) tests and corneal kindling studies were conducted to assess whether there were chronic alterations in seizure susceptibility and kindling development. Studies were conducted in both B6 and SJL/J mice to assess strain-dependent effects. RESULTS: Histopathologic analyses indicate that TMEV has specific tropism for limbic structures and causes widespread cell death in these regions. Results from ECT studies demonstrate that B6 mice that displayed acute symptomatic seizures have significantly reduced seizure thresholds and kindle faster than either control mice or infected mice without acute seizures. Furthermore, these effects were mouse-strain dependent, since SJL/J mice displayed a different seizure threshold spectrum. DISCUSSION: These findings indicate that Theiler's virus infection leads to chronically altered seizure susceptibility in mice. It is important to note that Theiler's virus infection of B6 mice represents a novel model to study postinfection hyperexcitability.


Subject(s)
Enterovirus Infections/complications , Seizures/etiology , Seizures/virology , Theilovirus/pathogenicity , Animals , Brain/pathology , Brain/virology , Cell Death , Disease Models, Animal , Disease Susceptibility/immunology , Disease Susceptibility/pathology , Kindling, Neurologic/genetics , Kindling, Neurologic/metabolism , Male , Mice , Mice, Inbred Strains , Psychomotor Disorders/etiology , Psychomotor Disorders/virology , Seizures/diagnosis , Seizures/immunology , Seizures/pathology , Spinal Cord/pathology , Spinal Cord/virology , Theilovirus/immunology
15.
Biochem Pharmacol ; 78(12): 1428-37, 2009 Dec 15.
Article in English | MEDLINE | ID: mdl-19682439

ABSTRACT

Epilepsy is a common seizure disorder affecting approximately 70 million people worldwide. Current pharmacotherapy is neuron-centered, frequently accompanied by intolerable side effects, and fails to be effective in about one third of patients. Therefore, new therapeutic concepts are needed. Recent research suggests an astrocytic basis of epilepsy, presenting the possibility of novel therapeutic targets. In particular, dysfunction of the astrocyte-controlled, endogenous, adenosine-based seizure control system of the brain is implicated in seizure generation. Thus, astrogliosis - a pathological hallmark of the epileptic brain - is associated with upregulation of the adenosine-removing enzyme adenosine kinase (ADK), resulting in focal adenosine deficiency. Both astrogliotic upregulation of ADK in epilepsy and transgenic overexpression of ADK are associated with seizures, and inhibition of ADK prevents seizures in a mouse model of pharmacoresistant epilepsy. These findings link adenosine deficiency with seizures and predict that adenosine augmentation therapies (AATs) will likely be effective in preventing seizures. Given the wide-spread systemic and central side effects of systemically administered AATs, focal AATs (i.e., limited to the astrogliotic lesion) are a necessity. This Commentary will discuss the pharmacological rationale for the development of focal AATs. Additionally, several AAT strategies will be discussed: (1) adenosine released from silk-based brain implants; (2) adenosine released from locally implanted encapsulated cells; (3) adenosine released from stem cell-derived brain implants; and (4) adenosine augmenting gene therapies. Finally, new developments and therapeutic challenges in using focal AATs for epilepsy therapy will critically be evaluated.


Subject(s)
Adenosine/physiology , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Adenosine/administration & dosage , Adenosine/pharmacology , Adenosine Kinase/drug effects , Animals , Astrocytes/drug effects , Brain/cytology , Brain/drug effects , Drug Delivery Systems , Drug Implants , Epilepsy/therapy , Genetic Therapy , Humans , Mice , Neuroglia/drug effects , Rats , Stem Cells/physiology
16.
Nurs Stand ; 23(11): 59-60, 2008.
Article in English | MEDLINE | ID: mdl-19054984
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