Yutaka Hirashima

Teikyo University, Edo, Tōkyō, Japan

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Publications (120)201.49 Total impact

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    Masaru Doshi · Yutaka Hirashima

    Full-text · Chapter · Mar 2012
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    ABSTRACT: Free radicals and lipid peroxidation are thought to be related to the vasospasm generation after subarachnoid hemorrhage (SAH). Plasma platelet-activating factor-acetyl hydrolase (PAF-AH) degrades phospholipids with an oxidatively modified fatty acyl chain. To compare plasma PAF-AH activity and free forms of biomarker of lipid peroxidation in cerebrospinal fluid (CSF) between patients with and without symptomatic vasospasm (SVS) after SAH. The identification of PAF-AH in CSF was performed by Western blotting. The genotype at position 279 of the plasma PAF-AH gene was determined. The activities of PAF-AH and the levels of free 8-iso-prostaglandin F2α (free isoPs), free hydroxyoctadecadienoic acid (free HODE), and free hydroxyeicosatetraenoic acid (free HETE) in CSF were measured. The PAF-AH in CSF was confirmed to be only the plasma type. The genotype of the plasma PAF-AH was not different between patients with and without SVS. Free isoPs, free HODE, and free HETE showed higher values in patients without SVS in 0 to 4 days and 5 to 9 days after SAH. The PAF-AH activity also was higher in patients without SVS in 0 to 4 days and 5 to 9 days after SAH. The associations between PAF-AH activity and free isoPs, and between PAF-AH activity and free HODE were significant. Oxidized lipids of lipoproteins and blood cell membranes produced by reactive oxygen species in CSF when SAH occurs may be the main source of lipid peroxidation. Plasma PAF-AH can hydrolyze oxidized phospholipids, and may attenuate the spreading of lipid peroxidation and participate in defense mechanisms against vasospasm after SAH.
    No preview · Article · Aug 2011 · Neurosurgery
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    Masaru Doshi · Etsuka Higuchi · Yutaka Hirashima
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    ABSTRACT: In our previous paper, we reported that spon-taneous hypothermia (HT) during ischemia protects against delayed neuronal death in the hippocampus but not against acute brain edema following tran-sient forebrain ischemia, which is induced by occlu-sion of the bilateral common carotid arteries (BCCA) in C57BL/6J mice. We here demonstrate that arti-ficial HT after reperfusion (rHT) suppresses the ag-gravation of acute brain edema in the BCCA occlu-sion C57BL/6J mouse model. Our results suggest that mechanisms regulated by rHT are involved in the at-tenuation of acute brain edema after reperfusion in this model of cerebral ischemia.
    Full-text · Article · Feb 2011 · Journal of health science
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    ABSTRACT: C57BL/6J mice are widely used as a background strain for genetic alterations and have been valuable for investigating the molecular mechanism of selective neuronal death following transient forebrain ischemia, which was induced by occlusion of bilateral common carotid arteries (BCCA). Hypothermia (HT) during ischemia has been shown to protect against neuronal death in several experimental models of cerebral ischemia including that induced by BCCA occlusion in C57BL/6J mice. In this study, we demonstrated that brain edema, one of the most important disorders following cerebral ischemia, occurred in the forebrain before neuronal death in the hippocampus and was not prevented by HT during cerebral ischemia induced by BCCA occlusion in C57BL/6J mice. Our results indicate that neuronal death and acute brain edema were induced by different mechanisms in the BCCA occlusion and reperfusion C57BL/6J mouse model, suggesting that our model with and without HT during cerebral ischemia may be a useful tool for the investigation of the specific mechanism of brain edema and neuronal death, respectively.
    No preview · Article · Dec 2009 · Biological & Pharmaceutical Bulletin
  • Yutaka Hirashima · Marika Ito · Masaru Doshi · Midori Kunii · Naoko Ideguchi
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    ABSTRACT: The present study was conducted to evaluate the relationship between the structure of anxiety and the self-educational ability in new pharmacists. Ninety seven new pharmacists rated the 42 items of our anxiety scale toward working in the pharmacy in June and October, 2006 and 40 items of established self-educational ability scale in June, 2006. A factor analysis of anxiety scale indicated four factors including communication ability, professional technique of pharmacist, working condition, and self-respecting. From the evaluation of correlation between factors of anxiety scale and factors of self-educational ability scale, the anxiety concerning communication ability or the problem concerning self-respecting correlated significantly with the poorness of all four factors of self-educational ability such as the aim of self-growth and self-development, self-objectifying, practice and technique of study, and self-confidence and pride. However, working condition did not correlate all four factors. For 4 months, the anxiety of professional technique of pharmacist decreased significantly although three other factors did not indicated significant changes.
    No preview · Article · Jun 2009 · Yakugaku zasshi journal of the Pharmaceutical Society of Japan
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    ABSTRACT: It is said atheromatous plaque is located very focally, but there have been few reports regarding this matter. Various aspects of the pathogenesis of the development of atheromatous plaque at the carotid bifurcation have previously been discussed. We have noted the correlation of plaque localization with characteristics of the cervical carotid artery wall. Morphological and histopathologic changes in the carotid bifurcation were examined in 72 cadaver cases with or without atheromatous plaque. We determined the level at which the wall structure changed to muscular artery from elastic artery and analyzed its influence on the development of atheromatous plaque. Atheromatous plaques at the distal site of the ICA extended within 0 to 37 mm from the carotid bifurcation. The proximal side of the CCA more than 5 mm away from the bifurcation was elastic artery, whereas the distal side of the ICA more than 15 mm from the bifurcation was muscular artery. The area of the carotid bifurcation between elastic artery and muscular artery was a transitional zone. Approximately 80% of them were located within 15 mm, and these areas were coincident with the transitional zone. Most atheromatous plaque was located in the transitional zone. The arterial wall structure is related to the development of atheromatous plaque at the cervical carotid bifurcation.
    No preview · Article · Jul 2008 · Surgical Neurology
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    ABSTRACT: The sex difference in the seasonal occurrence of subarachnoid hemorrhage (SAH) and the association of meteorological factors in Japan were analyzed in 1006 consecutive patients with SAH in Toyama, Japan from 1996 to 2000. The study investigated whether these meteorological factors could explain the seasonality of the incidence of SAH in each sex. Seasonal variation of SAH occurrence peaked in spring in men, but peaked in spring and winter in women. The difference between maximum temperature and minimum temperature was the greatest on the day previous to SAH occurrence in multiple individuals in men, whereas mean humidity was the greatest on that day in women. Interestingly, the difference between maximum temperature and minimum temperature peaked in spring and mean humidity in winter from the meteorological data over the 5 years. The relationship between humidity and occurrence of SAH may explain the sex difference of the incidence of aneurysmal SAH. The humidity change may be a specific and additional meteorological factor for the incidence of SAH in women.
    No preview · Article · Apr 2008 · Neurologia medico-chirurgica
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    Osamu Fukuda · Yutaka Hirashima · Hideki Origasa · Shunro Endo
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    ABSTRACT: The rate of head injury is 1.86-6 times higher for snowboarding than for skiing. Detailed data about the usefulness of a helmet or knit cap for protecting against serious head injuries have not been reported. The present study evaluated the use of a helmet or knit cap for preventing head injuries. Questionnaire data were collected from 1,190 consecutive patients in a hospital during the 1999/2000-2002/2003 winter seasons at Uonuma ski resort, Niigata, Japan. Patients were divided into the helmet, knit cap, and no cap groups. Upper technical level was highest and jumping as the cause of injury was most frequent in the helmet group. After adjustment for other confounders, there was a significant negative association between the occurrence of serious head injury during snowboarding and female sex (adjusted odds ratio 0.55, 95% confidence interval 0.421-0.718, p < 0.0001) and a significant positive association between serious head injury and jumping (adjusted odds ratio 2.25, 95% confidence interval 1.48-3.43, p = 0.0001). Among snowboarding maneuvers, only jumping showed a significant negative association between wearing of a helmet or knit cap and the occurrence of serious head injury (p = 0.036). Snowboarders who wear helmets might attempt dangerous maneuvers causing injuries. Wearing of a helmet or knit cap protected against serious head injuries on jumping. Every snowboarder should wear a helmet or knit cap on jumping to prevent head injury.
    Preview · Article · Nov 2007 · Neurologia medico-chirurgica
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    ABSTRACT: Cognitive functions are frequently impaired in patients with normal pressure hydrocephalus (NPH). Two patients with NPH initially had dysfunctional constructional skill but exhibited improvements after shunt surgery. Dysfunction of constructional skill should be added to the important clinical features of NPH. The geometric test can be used as a practical tool for evaluation of parietal lobe function in patients with NPH.
    Full-text · Article · Aug 2007 · Neurologia medico-chirurgica
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    ABSTRACT: Platelet-activating factor (PAF) and oxidized unsaturated free fatty acids have been postulated to aggravate neuronal damage in the postischemic brain. Type II PAF-acetylhydrolase (PAF-AH II) not only terminates signals by PAF by its PAF-hydrolyzing activity but also protects cells against oxidative stress. We examined whether PAF-AH II can rescue cerebral neurons against ischemic insults. Transgenic mice overexpressing human PAF-AH II in neurons were generated and enzyme expressions were examined biochemically and histochemically. The mice were subjected to 60 minutes of transient middle cerebral artery occlusion followed by reperfusion for 24 hours. The infarction and apoptosis were estimated by TTC staining and fluorescence TUNEL staining, respectively. Overexpression of PAF-AH II was found in brains of transgenic mice by Western blot and enzymatic activity analyses. In immunohistochemistry, human PAF-AH II expression was found throughout the central nervous system, especially in neurons of neocortex, hippocampus, and basal ganglia. The neurological deficit scores, cerebral edema index, and relative infarction volume were all significantly (P<0.05) lower in transgenic mice (1.30+/-0.72, 1.12+/-0.04, and 14.0+/-7.7%, respectively) than in wild-type mice (2.56+/-0.93, 1.23+/-0.12, and 31.9+/-9.7%, respectively). Percentages of apoptotic cells were also significantly (P<0.001) lower in transgenic mice (cortex, 5.2+/-3.3%; hippocampus, 3.4+/-7.0%) than in wild-type mice (cortex, 41.1+/-16.9%; hippocampus, 58.9+/-15.3%). These results indicate that PAF-AH II exerts strong neuroprotective effects against ischemic injury and suggest a possibility for clinical use of this enzyme in cerebral ischemia.
    Full-text · Article · Mar 2007 · Stroke
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    ABSTRACT: The intracranial internal carotid artery (ICA) is well known to be a muscular artery that lacks an external elastic lamina. Elastic fibers are concentrated inside the internal elastic lamina of the wall of the intracranial ICA. We examined a portion where the external elastic lamina disappeared in the course of the ICA. We extirpated 32 intracranial ICA specimens from 50 cadavers. We made running specimens of the ICA every 3 mm and stained them using the Elastica van Gieson method and then investigated a portion where the external elastic lamina disappeared in the wall of the ICA. We also examined the intimal thickness of various portions of the ICA. We identified both the internal elastic lamina and the external elastic lamina in the petrous portion of the ICA in all cases. In the intradural portion of the ICA, the external elastic lamina was not recognized and only the internal elastic lamina was seen in all cases. In 31 of the 32 specimens (98%), the external elastic lamina disappeared in the horizontal portion of the cavernous portion of the ICA. The intimal thickness of the ICA was recognized in 23/32 specimens. The starting point of the intimal thickness approximated the portion where the external elastic lamina disappeared. The external elastic lamina of the ICA disappeared at the horizontal portion of the cavernous sinus, which was a site where intimal thickness was frequently observed. Changes in the elasticity of the wall of the intracranial ICA may therefore cause atherosclerotic changes in the ICA.
    No preview · Article · Jan 2007 · Surgery for Cerebral Stroke
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    ABSTRACT: The authors describe the clinical features of headache in patients with vertebrobasilar artery dissection (VBAD) and emphasize the importance of recognition of warning headaches preceding subarachnoid hemorrhage. Headache in VBAD is already recognized, but the natural history and clinical features of the warning headache have not been well elucidated. The clinical features of 30 patients with VBAD were analyzed retrospectively. Of the 30 VBAD patients, 16 presented with subarachnoid hemorrhage and 14 with ischemia. Headache (without any other symptoms or signs) was detected in 70% of patients with subarachnoid hemorrhage and 50% of patients with infarction. The headache started acutely, was localized to the occiput or nape of the neck, was sharp and severe in intensity, and was different from any previously experienced headaches. The interval from onset of headache to diagnosis of subarachnoid hemorrhage or infarction was 1 to 10 days. Three patients had sudden severe warning headaches without any evidence of subarachnoid hemorrhage at initial presentation and deteriorated within 24 hours due to subarachnoid hemorrhage, demonstrated later on computed tomography. Angiographic findings of patients with warning headaches were nonspecific compared with those of patients without headache. The present study confirms a high frequency of headache in patients with VBAD. Sudden severe occipital and nuchal pain, even without subarachnoid hemorrhage or any neurologic deficit, should be considered as a warning sign of subarachnoid hemorrhage. Computed tomography, magnetic resonance imaging, and magnetic resonance angiography should be performed urgently for screening of patients with a warning headache to prevent resultant life-threatening major vascular events.
    No preview · Article · Mar 2006 · Clinical Journal of Pain
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    ABSTRACT: Inflammatory reaction is very important for formation of the neomembrane of chronic subdural hematoma (CSDH). The present study evaluated medical treatment with the platelet-activating factor receptor antagonist, etizolam, for the resolution of CSDH, and the factors indicating surgery or conservative therapy. Alternate patients were assigned to the etizolam group or control group without medical treatment. Patients in the etizolam group received 3.0 mg etizolam per day for 14 days. A total of 53 patients were followed up for at least 6 months. Univariate analysis of differences in demographic characteristics, clinical findings, and initial computed tomography (CT) findings, and multiple logistic regression analysis of the relationship between etizolam treatment and requirement for surgery using age, sex, low density of hematoma on CT, and paresis as confounders were performed. Etizolam treatment (adjusted odds ratio [OR] 0.156, 95% confidence interval [CI] 0.024-0.999, p = 0.049) was negatively correlated with requirement for surgery. Low density of hematoma (adjusted OR 0.125, 95% CI 0.019-0.846, p = 0.033) was found to be an independent negative predictor, and paresis as an initial symptom (adjusted OR 6.35, 95% CI 1.04-38.7, p = 0.045) was an independent positive predictor of requirement for surgery. Etizolam administration can promote the resolution of CSDH, especially at the stage of hygroma appearing as low density on CT. Surgery is recommended if the patient presents with paresis.
    No preview · Article · Jan 2006 · Neurologia medico-chirurgica
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    ABSTRACT: In this study, we evaluated the difference in incidence of symptomatic vasospasm between ruptured aneurysms in the anterior and posterior circulation using multiple logistic regression analysis. A total of 145 consecutive patients who underwent surgery for aneurysms within 72 hours after subarachnoid hemorrhage (SAH) were studied. The ruptured aneurysm was in the anterior circulation in 128 patients (88.3%) and in the posterior circulation in 17 patients (11.7%). Forty patients (27.6%) had symptomatic vasospasm and 105 patients (72.4%) did not. Univariate and multivariate analyses were performed to assess relationships among various variables and the occurrence of symptomatic vasospasm after SAH. Finally, Grade III to V (Hunt and Hess grade) and Group 3 (Fisher's classification) on admission were found to be independently positively associated with the occurrence of symptomatic vasospasm while ruptured vertebrobasilar aneurysm were negatively associated. Although a poor clinical grade and a severe SAH classification on admission such as Hunt and Hess grade and Fisher's classification are established powerful predictors of symptomatic vasospasm, ruptured vertebrobasilar aneurysm are for the first time reported to be a predictor of symptomatic vasospasm based on results of a recent reliable statistical analysis.
    No preview · Article · Jan 2006 · Neurosurgery
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    ABSTRACT: Inflammatory reaction is very important for formation of the neomembrane of chronic subdural hematoma (CSDH). The present study evaluated medical treatment with the platelet-activating factor receptor antagonist, etizolam, for the resolution of CSDH, and the factors indicating surgery or conservative therapy. Alternate patients were assigned to the etizolam group or control group without medical treatment. Patients in the etizolam group received 3.0 mg etizolam per day for 14 days. A total of 53 patients were followed up for at least 6 months. Univariate analysis of differences in demographic characteristics, clinical findings, and initial computed tomography (CT) findings, and multiple logistic regression analysis of the relationship between etizolam treatment and requirement for surgery using age, sex, low density of hematoma on CT, and paresis as confounders were performed. Etizolam treatment (adjusted odds ratio [OR] 0.156, 95% confidence interval [CI] 0.024-0.999, p = 0.049) was negatively correlated with requirement for surgery. Low density of hematoma (adjusted OR 0.125, 95% CI 0.019-0.846, p = 0.033) was found to be an independent negative predictor, and paresis as an initial symptom (adjusted OR 6.35, 95% CI 1.04-38.7, p = 0.045) was an independent positive predictor of requirement for surgery. Etizolam administration can promote the resolution of CSDH, especially at the stage of hygroma appearing as, low density on CT. Surgery is recommended if the patient presents with paresis.
    Preview · Article · Dec 2005 · Neurologia medico-chirurgica
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    ABSTRACT: A 50-year-old man had undergone right nucleus ventrointermedius (Vim) thalamotomy 1 year previously, resulting in the disappearance of left hand tremor. However, he presented with right distal and proximal tremor including the axial trunk, neck, and head. Deep brain stimulation (DBS) of the left Vim for these symptoms was unsuccessful. Attempts were made to stimulate the left Vim, nucleus ventralis lateralis, and subthalamic nucleus (STN), but no significant improvement was obtained after repeat surgery. However, subsequent improvement of the symptoms including proximal tremor was very marked even without DBS stimulation. Brain magnetic resonance imaging demonstrated lesion and edema in the posteromedial area of the STN. Mechanical injury of the area caused by the surgical procedures may have contributed to the improvement in his persistent symptoms.
    Full-text · Article · Oct 2005 · Neurologia medico-chirurgica
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    ABSTRACT: Nuclear factor (NF)-kappaB is known to control cellular proliferation and apoptosis. In malignant astrocytoma cells, it was reported that NF-kappaB was activated aberrantly and promoted their proliferation. Thus, inhibition of NF-kappaB activity is considered to be a promising therapeutic strategy for malignant astrocytoma. Recently, curcumin, the major constituent of turmeric, was reported to inhibit NF-kappaB activity. In this study, we investigated inhibitory effects of curcumin on NF-kappaB activity and cellular proliferation, and induction of apoptosis by curcumin in human malignant astrocytoma cell lines. Alteration of NF-kappaB activity in NP-2 human malignant astrocytoma cell line after treatment with curcumin was examined using electrophoretic mobility shift assay. Alterations of DNA synthesis and cellular growth in five human malignant astrocytoma cell lines after treatment with curcumin were examined using [(3)H]thymidine incorporation assay and the trypan blue dye exclusion method, respectively. Induction of apoptosis by curcumin in NP-2 and NP-3 human malignant astrocytoma cell lines was examined by DNA-fragmentation analysis and morphological observation. We found that the NF-kappaB activity in NP-2 was significantly reduced by curcumin. The DNA synthesis and the cellular growth were inhibited by curcumin in dose-dependent manner in all the five malignant astrocytoma cell lines. Nuclear condensation and fragmentation, and DNA fragmentation were observed in both NP-2 and NP-3 after the treatment with curcumin. These results indicate that curcumin inhibits the cellular proliferation and induces apoptosis in human malignant astrocytoma cell lines. These results are considered to be resulted from the inhibition of NF-kappaB activity by curcumin.
    No preview · Article · Oct 2005 · Journal of Neuro-Oncology
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    ABSTRACT: A 68-year-old man presented with occlusion of the internal carotid artery (ICA) manifesting as a 6-month history of progressive sensory and motor disturbance of the left lower limb. Angiography clearly demonstrated a collateral arterial network between the ICA and external carotid artery (ECA) through the vidian artery, a small branch of both the ICA and ECA. The vidian artery may form an unusual but important ECA-ICA collateral pathway in patients with occlusive lesion of the ICA.
    No preview · Article · Oct 2005 · Neurologia medico-chirurgica
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    ABSTRACT: A 68-year-old man presented with occlusion of the internal carotid artery (ICA) manifesting as a 6-month history of progressive sensory and motor disturbance of the left lower limb. Angiography clearly demonstrated a collateral arterial network between the ICA and external carotid artery (ECA) through the vidian artery, a small branch of both the ICA and ECA. The vidian artery may form an unusual but important ECA-ICA collateral pathway in patients with occlusive lesion of the ICA.
    No preview · Article · Sep 2005 · Neurologia medico-chirurgica
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    ABSTRACT: Increased platelet consumption is expected in patients with cerebral vasospasm, according to data from clinical and experimental studies. The authors investigated sequential changes in platelet counts in patients with subarachnoid hemorrhage (SAH) and the difference in platelet consumption between patients with and those without symptomatic vasospasm (SV). Variables related to platelet count as well as other clinical and radiological variables were analyzed as independent predictors of SV. One hundred consecutive patients who had undergone surgery within 48 hours after SAH onset were entered in the study. Clinical and radiological variables and blood cell counts, including red blood cells, white blood cells, and platelets, after SAH were retrospectively examined. Twenty of these variables were entered into univariatete and multivariate analyses to determine predictors for SV. After SAH, the platelet count decreased to a minimum and then increased rapidly to levels greater than those recorded on admission. This change was specific to SAH, and platelet consumption was more severe in patients with SV than in those without. There were three independent predictors of SV: a ratio of the lowest platelet count and the admission count greater than 0.7 (odds ratio [OR] 0.322, 95% confidence interval [CI] 0.124-0.834, p = 0.0196) and a history of hypertension (OR 0.338, 95% CI 0.126-0.906, p = 0.0311) were negatively significant (that is, decreases the occurrence of SV), and a Fisher Grade 3 (OR 4.42, 95% CI 1.48-13.2, p = 0.0077) was positively significant (that is, increases the occurrence of SV). The association between a decrease in platelet count and the occurrence of SV indicates the important role of platelets in the pathophysiology of vasospasm following SAH.
    No preview · Article · Jun 2005 · Journal of Neurosurgery

Publication Stats

1k Citations
201.49 Total Impact Points

Institutions

  • 2007-2011
    • Teikyo University
      • Faculty of Pharmaceutical Sciences
      Edo, Tōkyō, Japan
  • 2008
    • Toyama University
      Тояма, Toyama, Japan
  • 1988-2006
    • Toyama Medical and Pharmaceutical University
      Тояма, Toyama, Japan
  • 1999
    • Iwate Medical University
      • Department of Neurosurgery
      Morioka, Iwate, Japan
  • 1989-1999
    • The Ohio State University
      • Department of Molecular and Cellular Biochemistry
      Columbus, Ohio, United States
  • 1990
    • Columbus State University
      Columbus, Georgia, United States