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Kenichi Komatsu

Publications and source records attributed to Kenichi Komatsu.

16 recordsLinked to original sources
PubMed2006

Heterogeneous factors in dementia with Parkinson's disease: IMP-SPECT study.

BACKGROUND: Nature of the dementing process in Parkinson's disease, and particularly its relationship with Alzheimer's disease, diffuse Lewy body disease or frontal dementia remains controversial. OBJECTIVE: We hypothesize that origins of dementia in Parkinson's disease are heterogeneous, so we compared cortical regional cerebral blood flow (rCBF) between Parkinson's disease patients with and without dementia. PATIENTS: Forty consecutive patients with Hoehn-Yahr stage III or IV Parkinson's disease were used (13 patients had dementia (PDD group), and 27 patients had no dementia (PDND group)). RESULTS: There were significant rCBF reductions in the left parietal association cortex and left frontal association cortex in PDD. Multiple logistic regression analysis demonstrated that only rCBF of the left frontal association cortex was significant. PDD patients were divided into three groups according to rCBF patterns: frontal hypoperfusion group, Alzheimer's disease-like group, and diffuse Lewy body disease-like group. CONCLUSIONS: Controversial study results involving PDD patients may be mainly due to heterogeneity in dementing processes in Parkinson's disease.

Aged↗
PubMed2006

Disruptions of the fornix fiber in Parkinsonian patients with excessive daytime sleepiness.

BACKGROUND: Although excessive daytime sleepiness (EDS) in Parkinson's disease (PD) has received a great deal of attention, the underlying pathological mechanism of its development and the relative contributions of brain function to this process are poorly understood. OBJECTIVE: To compare the fractional anisotropy (FA) values of PD patients with EDS and those without EDS, and to investigate the mechanism of EDS in this disease. METHODS: Eleven patients with PD with EDS, 26 patients with PD without EDS and 10 controls participated in this study. Patients with an ESS (Epworth Sleepiness Scale) score >or=10 were defined as having EDS. The FA values of 5 regions of interest (ROI) including the fornix were compared between the three groups. RESULTS: There were significant reductions in FA values of the fornix fiber in patients with EDS. ESS scores had significant correlation with FA values of the fornix. CONCLUSIONS: Our study is the first to find the fornix fiber degeneration in PD patients with EDS. These results indicate that fornix dysfunction may have some correlations with EDS in PD.

Aged↗
PubMed2006

Wisconsin Card Sorting Test and brain perfusion imaging in Parkinson's disease.

BACKGROUND: Few imaging studies investigated frontal dysfunctions in Parkinson's disease. OBJECTIVES: We investigated relationships between Wisconsin Card Sorting Test (WCST) and brain perfusion in patients with non-demented Parkinson's disease. METHODS: Patients were divided into two groups according to WCST score: (1) CA (number of category achieved) or=3. We performed three-dimensional stereotactic surface projection and volume of interest analysis using (123)I-IMP scintigraphy. RESULTS: Hypoperfusions of the bilateral posterior cingulate, rostrodorsal prefrontal, and left frontopolar cortices were shown in CA<or=2 group, with the left cingulate and right rostrodorsal prefrontal cortices showing prominent hypoperfusion. CA and PE (perseverative errors) scores significantly correlated with perfusion of the left posterior cingulate cortex. PE score also correlated with perfusion of the right rostrodorsal prefrontal cortex. CONCLUSION: Data indicated participations of various regions in task achievement. Careful interpretation of WCST scores is required.

Aged↗
PubMed2006

Does cardiac metaiodobenzylguanidine (MIBG) uptake in Parkinson's disease correlate with major autonomic symptoms?

OBJECTIVES: To compare MIBG (metaiodobenzylguanidine) uptake between Parkinson's disease patients with and without autonomic symptoms to investigate meanings of MIBG scintigraphy and correlations between autonomic symptoms and MIBG uptake. METHODS: Forty consecutive patients with Hoehn-Yahr III or IV Parkinson's disease and 12 controls were enrolled. We compared cardiac MIBG uptake between patients with and without orthostatic hypotension. Similar comparisons were performed for constipation and bladder dysfunction. RESULTS: MIBG uptake did not significantly correlate with age, disease duration, Hoehn-Yahr stage, Unified Parkinson's Disease Rating Scale (UPDRS) motor score or levodopa equivalent daily doses. There were no significant correlations between orthostatic hypotension/constipation and cardiac MIBG uptake. Only bladder symptoms significantly correlated with MIBG uptake. CONCLUSION: Meanings of MIBG uptake abnormalities in Parkinson's disease and relationship between MIBG uptake and clinical parameters remain to be resolved in future studies.

3-Iodobenzylguanidine↗
PubMed2006

Minor depression and brain perfusion images in Parkinson's disease.

Depression is common in individuals with Parkinson's disease. However, the pathophysiology of depression in Parkinson's disease remains obscure. Here we compared brain perfusion images of Parkinson's disease patients with and without depression to investigate correlations between depression and brain perfusion images in Parkinson's disease. We divided 40 consecutive patients with Parkinson's disease into two groups: patients with minor depression (n = 22) and patients without depression (n = 18). We then compared brain perfusion images between the two groups. As a result, hypoperfusion of the left superior and inferior frontal gyrus was demonstrated in depressed patients. These results were partially in agreement with previous studies on de novo and parkinsonian major depression. We could not conclude on whether pathophysiological mechanisms differed between de novo depression and depression with Parkinson's disease, and between major and minor depressions.

Aged↗
PubMed2006

Hypoperfusion of the visual pathway in parkinsonian patients with visual hallucinations.

Little is known about the developing mechanisms of visual hallucinations in Parkinson's disease. This study aimed to investigate perfusion changes in parkinsonian patients with visual hallucinations using n-isopropyl-p-[123I]iodoamphetamine ([123I]IMP) single photon emission computed tomography imaging. A total of 70 consecutive patients, including 31 patients with visual hallucinations, and 39 patients without hallucinations, participated in this study. Patients with severe cognitive impairment (Mini-Mental State Examination score < 20), nonvisual hallucinations, or confusion were excluded. We compared brain perfusion changes between the two groups. We found that hallucinatory patients had significant perfusion reductions in the bilateral inferior parietal lobule, inferior temporal gyrus, precuneus gyrus, and occipital cortex compared to nonhallucinatory patients. These results suggested that hypoperfusion of the visual pathway was closely related to visual hallucinations in Parkinson's disease.

Aged↗
PubMed2006

Hypoperfusion of the auditory and prefrontal cortices in Parkinsonian patients with verbal hallucinations.

We examined patients with and without auditory hallucinations, using n-isopropyl-p-[123I]iodoamphetamine single photon emission computed tomographic imaging. We assessed verbal hallucinations in the present study: patients with nonverbal auditory hallucinations were excluded. A total of 11 patients with verbal and visual hallucinations and 17 patients with visual hallucinations only were enrolled. Patients with both verbal and visual hallucinations revealed significant hypoperfusion in the bilateral prefrontal cortex and right superior temporal gyrus compared to patients with visual hallucinations only. There were no significant hyperperfusion in patients with verbal plus visual hallucinations. These results may support the release hallucination theory in verbal hallucinations of Parkinson's disease, although another explanations may be more appropriate and further studies are required.

Aged↗
PubMed2006

Excessive daytime sleepiness in Parkinson disease: a SPECT study.

STUDY OBJECTIVES: The underlying pathologic mechanism of excessive daytime sleepiness (EDS) in Parkinson disease and the relative contributions of brain function to this process are poorly understood. We compared brain perfusion images between patients with Parkinson disease and EDS and those without EDS using n-isopropyl-p-1231 iodoamphetamine single photon emission computed tomography. DESIGN: Clinical study. SETTING: Sumitomo Hospital. PATIENTS: Thirteen patients with Parkinson disease with EDS (EDS group) and 27 patients with Parkinson disease without EDS (no-EDS group) were studied. Whether or not each case had EDS was determined according to the response to the Epworth Sleepiness Scale: patients with an Epworth Sleepiness Scale score > or = 10 were included in the EDS group, and patients with an Epworth Sleepiness Scale score < or = 9 were included in the no-EDS group. MEASUREMENTS AND RESULTS: There were significant hypoperfusions in the left parietal and temporal association cortex in the EDS group. In the multivariable logistic regression model, attention and decreased regional cerebral blood flow of the left parietal association cortex and right caudate and increased regional cerebral blood flow of the right thalamus were the independent and significant factors. CONCLUSIONS: The cortical hypofunction relative to hyperfunction of the brain stem may relate to EDS in Parkinson disease. This is the first imaging study about EDS in Parkinson disease, and further studies are required.

Aged↗
PubMed2006

Autoimmune pancreatitis and complement activation system.

OBJECTIVES: Autoimmune pancreatitis is characterized by increased serum level of IgG4, but its pathogenesis has not been fully elucidated. Because this disease is occasionally associated with decreased levels of complements, we sought to clarify which complement activation system was operating in its active state. METHODS: We measured serum levels of complements, mannose-binding lectin, and circulating immune complex in patients with autoimmune pancreatitis, patients with chronic pancreatitis, and healthy controls. RESULTS: We found high serum circulating immune complex values, which decreased significantly after corticosteroid therapy. In patients with autoimmune pancreatitis, elevated levels of circulating immune complex, as determined by C1q assay, were significantly associated with increased serum levels of IgG1 and decreased levels of C4, as well as with a tendency toward decreased levels of C3. There were no significant differences in the serum levels of mannose-binding lectin or in the frequency of a mutant allele of mannose-binding lectin between patients with autoimmune pancreatitis and those with chronic calcifying pancreatitis. Furthermore, corticosteroid therapy had no effect on the level of mannose-binding lectin. CONCLUSIONS: Autoimmune pancreatitis exhibits a high serum circulating immune complex values in its active state, which links to a complement activation system with a classic pathway rather than the mannose-binding lectin pathway or alternative pathways.

Adult↗
PubMed2005

Corticosteroid-responsive pancreatic cyst found in autoimmune pancreatitis.

There have been only a few reports of autoimmune pancreatitis complicated with pancreatic cyst and such cysts are rare, probably due to the absence of severe tissue necrosis and/or lack of stasis of the pancreatic juice in this condition. However, during a follow-up of 48 patients with this disease, we found 3 patients with pancreatic cysts, and this enabled us to evaluate their clinicopathological findings. Between September 1994 and July 2003, we treated and followed 48 patients with autoimmune pancreatitis, and found 3 patients with pancreatic cyst formation that was responsive to corticosteroid therapy. All of the patients with cysts had high serum IgG4 concentrations. After corticosteroid therapy, rapid resolution of the pancreatic cysts was observed. Immunostaining with goat polyclonal antibody for each IgG subclass showed severe infiltration of IgG4-positive plasma cells in the cyst wall in one patient. The high serum IgG4 concentration and favorable response to corticosteroid therapy suggests that a highly active state of the inflammatory process is closely associated with cyst formation, and that a corticosteroid-responsive pancreatic cyst is a characteristic feature of autoimmune pancreatitis.

Antibodies, Antinuclear↗
PubMed2005

High prevalence of hypothyroidism in patients with autoimmune pancreatitis.

Autoimmune pancreatitis is a unique form of chronic pancreatitis and has been correlated with various extrapancreatic lesions. To search for a correlation between autoimmune pancreatitis and thyroid lesions, we measured thyroid functions in 41 patients with autoimmune pancreatitis and in 41 patients with chronic calcifying pancreatitis and investigated the correlation between HLA antigens and hypothyroidism. We found a significant difference in the prevalence of antithyroglobulin antibody and hypothyroidism between patients with autoimmune pancreatitis and those with chronic pancreatitis (34.1 vs. 7.3%, P = 0.005, and 26.8 vs. 0%, P = 0.0005, respectively). Patients with hypothyroidism had a significantly higher frequency of antithyroglobulin antibody (63.6%) than those without hypothyroidism but showed no differences in other findings, including serum IgG4 concentration. We could find no significant association between any HLA antigens and the hypothyroid state of autoimmune pancreatitis. One quarter of the patients with autoimmune pancreatitis have hypothyroidism that may be independent of the active state of the pancreatic lesion or systemic fibrosing disorder, and thus patients suspected of having autoimmune pancreatitis should be evaluated for possible hypothyroidism.

Adult↗
PubMed2005

Immunoglobulin G4-related lymphoplasmacytic sclerosing cholangitis that mimics infiltrating hilar cholangiocarcinoma: part of a spectrum of autoimmune pancreatitis?

BACKGROUND: Autoimmune pancreatitis has been designated as sclerosing pancreatocholangitis, because this disease shows a high prevalence of bile-duct lesions. We present herein the clinical characteristics of unusual cases that show dominant bile-duct lesions and mimicking infiltrating hilar cholangiocarcinomas. METHODS: Clinical and pathologic findings of 3 patients with immunoglobulin (Ig) G4 related sclerosing cholangitis who had no apparent pancreatic lesions comparable with autoimmune pancreatitis were analyzed. OBSERVATIONS: All patients were middle-aged or elderly individuals with slightly elevated serum IgG4 concentrations and showed long-segment narrowing of the bile-duct system, mimicking infiltrating hilar cholangiocarcinoma without significant pancreatic change. The first patient was treated with a corticosteroid, resulting in amelioration of the narrowing of the bile duct. The second patient underwent surgery based on a diagnosis of cholangiocarcinoma. In the third patient, the bile-duct stricture reversed spontaneously 1 month after the drainage procedure. Pathologic findings of the bile ducts for all patients disclosed significant lymphoplasmacytic infiltration, including abundant IgG4-bearing plasma cells. CONCLUSIONS: The use of IgG4 immunostaining in biopsy specimens of the bile duct may identify the presence of corticosteroid-responsive lymphoplasmacytic sclerosing cholangitis.

Aged↗
PubMed2004

Recurrent attacks of autoimmune pancreatitis result in pancreatic stone formation.

OBJECTIVES: Autoimmune pancreatitis has been characterized by irregular narrowing of the main pancreatic duct and sonolucent swelling of the parenchyma, both of which are due to lymphoplasmacytic inflammation at the active stage of the disease, and by the absence of pancreatic stone formation. The aim of the present study was to confirm or deny whether or not this disease is progressive with recurrent attacks, resulting in pancreatic stone formation like ordinary chronic pancreatitis. METHODS: Forty-two patients, 36 of whom were treated with prednisolone, were followed up for periods longer than 12 months (median follow-up period: 54.5 months, range: 13-111 months) by regular interview and examination of their medical records for laboratory tests and image tests. RESULTS: Eleven patients (26.2%) who were treated with prednisolone showed recurrent attacks during median follow-up periods of 22 months. Eight patients (19%) showed the formation of pancreatic stones during the follow-up periods. Because 6 of 11 patients (54.5%) who suffered relapse showed pancreatic stone formation, it is significantly associated with relapse in comparison with nonrelapse (p= 0.0019). CONCLUSIONS: Contrary to previous reports, we observed both relapse and pancreatic stone formation in some patients with autoimmune pancreatitis, which suggests that autoimmune pancreatitis has the potential to be a progressive disease with pancreatic stones.

Aged↗
PubMed2002

Synthesis, biological evaluation, and quantitative structure-activity relationship analysis of new Schiff bases of hydroxysemicarbazide as potential antitumor agents.

Thirty Schiff bases of hydroxysemicarbazide (Ar-CH=NNHCONHOH) have been synthesized and tested against L1210 murine leukemia cells. The IC(50) values were found to be in a range from 2.7 x 10(-6) to 9.4 x 10(-4) M. A total of 17 out of the 30 compounds had higher inhibitory activities than hydroxyurea (an anticancer drug currently used for the treatment of melanoma, leukemia, and ovarian cancer) against L1210 cells. Six compounds with IC(50) values in micromolar range were 11- to 30-fold more potent than hydroxyurea (IC(50) = 8.2 x 10(-5) M). The partition coefficient (log P) and ionization constants (pK(a)) of a model compound [1-(3-trifluoromethylbenzylidene)-4-hydroxysemicarbazide, 1] were measured by the shake-flask method, and the measured log P was used to derive Hansch-Fujita pi constant of -CH=NNHCONHOH. On the basis of the newly derived pi and those of other moieties, the partition coefficients (SlogP) of the other 29 compounds were calculated by the summation of pi values. Quantitative structure-activity relationship (QSAR) analysis showed that, besides the essential pharmacophore (-NHCONHOH), hydrophobicity (SlogP), molecular size/polarizability (calculated molar refractivity), and the presence of an oxygen-containing group at the ortho position (I) were important determinants for the antitumor activities. In conclusion, the results obtained in this study show that several Schiff bases of hydroxysemicarbazide are potent inhibitors of tumor cells and warrant further investigation as cancer chemotherapeutic agents.

Animals↗
PubMed2002

Melting and incineration plants of municipal waste. Chemical and biochemical diagnosis of thermal processing samples (emission, residues).

Control of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in emissions and thermal residues from incinerators has been a cause of public concern for more than one decade. Recently, several studies showed that other persistent organic pollutants (POPs) such as coplanar polychlorinated biphenyls (co-PCBs) also have dioxin-like activity and are released from incinerators. Therefore, the present study was aimed at making a risk assessment about dioxin-like activity in extracts of thermal waste residues (e.g. combustion gas; fly ash, slag) from incineration and melting processes in Germany and Japan. For this purpose, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (co-PCBs), polychlorinated naphthalenes (PCNs) and polyaromatic hydrocarbons (PAHs) were analyzed by chemical analysis. Additionally, 2, 3, 7, 8-TCDD equivalents (EROD-TEQs) were determined by in vitro Micro-EROD bioassay using rat H4IIE hepatoma cells. EROD-TEQs could be correlated to I-TEQ values (from PCDD/Fs/co-PCBs) analyzed by chemical analysis resulting in a maximal sixfold higher estimate. Our study indicates minor influences of co-PCBs, PAHs and PCNs to the sum of dioxin-like toxicity in the extracts of thermal waste residues as determined here. Furthermore, we showed that the levels of dioxins and co-PCBs contained in slag from melting processes and bottom ashes from incineration processes were lower by 1-2 orders of magnitude than that in fly ash.

Air Pollutants↗