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51.
Janne L?hdesm?ki Jukka Sallinen Ewen MacDonald Mika Scheinin 《Neuropsychopharmacology》2004,29(7):1282-1293
Amphetamines are commonly used to treat attention-deficit hyperactivity disorder, but are also widely abused. They are employed in schizophrenia-related animal models as they disrupt the prepulse inhibition (PPI) of the acoustic startle response. The behavioral effects of amphetamines have mainly been attributed to changes in dopamine transmission, but they also involve increases in the synaptic concentrations of norepinephrine (NE). alpha2-Adrenoceptors (alpha2-ARs) regulate the excitability and transmitter release of brain monoaminergic neurons mainly as inhibitory presynaptic auto- and heteroreceptors. Modulation of acoustic startle and its PPI by the alpha2A-AR subtype was investigated with mice lacking the alpha2A-AR (alpha2A-KO) and their wild-type (WT) controls, without drugs and after administration of the alpha2-AR agonist dexmedetomidine or the antagonist atipamezole. The interaction of D-amphetamine (D-amph) and the alpha2-AR-noradrenergic neuronal system in modulating startle reactivity and in regulating brain monoamine metabolism was assessed as the behavioral and neurochemical responses to D-amph alone, or to the combination of D-amph and dexmedetomidine or atipamezole. alpha2A-KO mice were supersensitive to both neurochemical and behavioral effects of D-amph. Brain NE stores of alpha2A-KO mice were depleted by D-amph, revealing the alpha2A-AR as essential in modulating the actions of D-amph. Also, increased startle responses and more pronounced disruption of PPI were noted in D-amph-treated alpha2A-KO mice. alpha2A-AR also appeared to be responsible for the startle-modulating effects of alpha2-AR drugs, since the startle attenuation after the alpha2-AR agonist dexmedetomidine was absent in alpha2A-KO mice, and the alpha2-AR antagonist atipamezole had opposite effects on the startle reflex in alpha2A-KO and WT mice. 相似文献
52.
Takuhiro Shoji Ryuta Saito Masayuki Kanamori Yukihiko Sonoda Mika Watanabe Teiji Tominaga 《Brain tumor pathology》2016,33(4):255-260
We present a case of sarcoma occurring at a site of resected oligodendroglioma without preceding radiotherapy or chemotherapy. Oligosarcoma occurring at sites of resected oligodendroglioma or anaplastic oligodendroglioma with sarcomatous components are rare. Although meningioma or sarcoma-like lesions are sometimes reported after glioma-targeted radiotherapy, those without preceding radiotherapy are quite rare. Moreover, cases of sarcoma without oligodendroglial components occurring at a site of resected oligodendroglioma have never been reported. In this case, fluorescent in situ hybridization analysis revealed 1p/19q co-deletion in both the first tumor and second tumors. Additionally, immunohistochemistry revealed mutated isocitrate dehydrogenase 1 in both tumors. Taken together, these findings suggest a monoclonal tumor origin. Consequently, this case may indicate a new mechanism of development of sarcomatous lesions occurring at the site of a resected glioma. 相似文献
53.
Xiaoyi Jin Tomoyuki Koike Takashi Chiba Yutaka Kondo Nobuyuki Ara Kaname Uno Naoki Asano Katsunori Iijima Akira Imatani Mika Watanabe Akio Shirane Tooru Shimosegawa 《Digestive endoscopy》2013,25(5):547-549
In the present paper, we report a case of rare collagenous gastritis. The patient was a 25‐year‐old man who had experienced nausea, abdominal distention and epigastralgia since 2005. Esophagogastroduodenoscopy (EGD) carried out at initial examination by the patient's local doctor revealed an extensively discolored depression from the upper gastric body to the lower gastric body, mainly including the greater curvature, accompanied by residual mucosa with multiple islands and nodularity with a cobblestone appearance. Initial biopsies sampled from the nodules and accompanying atrophic mucosa were diagnosed as chronic gastritis. In August, 2011, the patient was referred to Tohoku University Hospital for observation and treatment. EGD at our hospital showed the same findings as those by the patient's local doctor. Pathological findings included a membranous collagen band in the superficial layer area of the gastric mucosa, which led to a diagnosis of collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic findings to make a diagnosis. 相似文献
54.
55.
Reference Values for Echocardiography in Middle‐Aged Population: The Cardiovascular Risk in Young Finns Study
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Saku Ruohonen Ph.D Juha W. Koskenvuo M.D. Ph.D. Maria Wendelin‐Saarenhovi M.D. Ph.D. Mikko Savontaus M.D. Ph.D. Mika Kähönen M.D. Ph.D. Tomi Laitinen M.D. Ph.D. Terho Lehtimäki M.D. Ph.D. Eero Jokinen M.D. Ph.D. Jorma Viikari M.D. Ph.D. Markus Juonala M.D. Ph.D. Leena Taittonen M.D. Ph.D. Päivi Tossavainen M.D. Ph.D. Merja Kallio M.D. Ph.D. Jeroen J. Bax M.D. Ph.D. Olli Raitakari M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(2):193-206
56.
Kouji Kawai Tetsuya Sakairi Shuichi Harada Junko Shinozuka Mika Ide Hiroko Sato Masaharu Tanaka Wataru Toriumi Eisuke Kume 《Experimental and toxicologic pathology》2012,64(4):333-338
SHR/NDmcr-cp (SHR/NDcp) rats, which carry a nonsense mutation of the leptin receptor gene, are known to spontaneously develop hypertension, obesity and hyperlipidemia, and have therefore found use as an animal model of the metabolic syndrome and type 2 diabetes. However, some recent studies on SHR/NDcp rats revealed only mild elevation of blood glucose levels. To investigate whether metabolic factors including blood glucose and histopathological alterations of SHR/NDcp rats deteriorate with a diabetogenic diet, biochemical and histopathological examinations were conducted with animals fed normal or diabetogenic diets for 20 weeks. SHR/NDcp rats receiving the normal diet displayed obesity, hypertension, hyperlipidemia, and mild elevation of blood glucose and HbA1c levels. Urinary glucose excretion was noted in only 1 out of 6 animals. Histologically, macro- and micro-vesicular steatosis in the liver, glomerular and tubular damages in the kidney and islet hyperplasia mainly of beta cells in the pancreas were characteristically noted. In SHR/NDcp rats fed the diabetogenic diet, obesity was more severe, with higher blood glucose and HbA1c levels, increased numbers of animals with urinary glucose excretion, and more pronounced hepatic steatosis and renal tubular changes. However, elevation of blood glucose levels and urinary glucose excretion proved transient. These observations indicate that the diabetic state and associated histopathological alterations in SHR/NDcp rats are exacerbated by feeding a diabetogenic diet, but the effects are limited. Elevated islet function with compensative insulin secretion might be related to amelioration of the hyperglycemic state. Further diet modification could be needed to induce a more prominent and persistent diabetic state in SHR/NDcp rats. 相似文献
57.
58.
Jaana I. Halonen Jussi Vahtera Stephen Stansfeld Tarja Yli-Tuomi Paula Salo Jaana Pentti Mika Kivim?ki Timo Lanki 《Environmental health perspectives》2012,120(10):1391-1396
Background: Associations between traffic noise and sleep problems have been detected in experimental studies, but population-level evidence is scarce.Objectives: We studied the relationship between the levels of nighttime traffic noise and sleep disturbances and identified vulnerable population groups.Methods: Noise levels of nighttime–outdoor traffic were modeled based on the traffic intensities in the cities of Helsinki and Vantaa, Finland. In these cities, 7,019 public sector employees (81% women) responded to postal surveys on sleep and health. We linked modeled outdoor noise levels to the residences of the employees who responded to the postal survey. We used logistic regression models to estimate associations of noise levels with subjectively assessed duration of sleep and symptoms of insomnia (i.e., difficulties falling asleep, waking up frequently during the night, waking up too early in the morning, nonrestorative sleep). We also used stratified models to investigate the possibility of vulnerable subgroups.Results: For the total study population, exposure to levels of nighttime–outside (Lnight, outside) traffic noise > 55 dB was associated with any insomnia symptom ≥ 2 nights per week [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.05, 1.65]. Among participants with higher trait anxiety scores, which we hypothesized were a proxy for noise sensitivity, the ORs for any insomnia symptom at exposures to Lnight, outside traffic noises 50.1–55 dB and > 55 dB versus ≤ 45 dB were 1.34 (95% CI: 1.00, 1.80) and 1.61 (95% CI: 1.07, 2.42), respectively.Conclusions: Nighttime traffic noise levels > 50 dB Lnight, outside was associated with insomnia symptoms among persons with higher scores for trait anxiety. For the total study population, Lnight, outside > 55 dB was positively associated with any symptoms. 相似文献
59.
Mika Shigeta Minoru Saiki Daisuke Tsuruta Chika Ohata Norito Ishii Fumitake Ono Takahiro Hamada Teruki Dainichi Minao Furumura John J. Zone Sarolta Karpati Cassian Sitaru Takashi Hashimoto 《The Journal of dermatology》2012,39(12):1002-1005
Dermatitis herpetiformis (DH) is common in some Caucasian populations but extremely rare in Japanese, probably because of different immunogenetic backgrounds. We report two Japanese DH cases with typical clinical, histological and direct immunofluorescence features. However, no symptom of gluten‐sensitive enteropathy was shown. The diagnosis was confirmed by eliminating other autoimmune blistering diseases by indirect immunofluorescence, enzyme‐linked immunosorbent assays and immunoblotting. However, circulating immunoglobulin (Ig)A anti‐endomysium, reticulin and gliadin antibodies were not detected. IgA antibodies to tissue and epidermal transglutaminases were also negative. One case was associated with lung cancer and the other one with autoimmune pancreatitis. On review of 17 cases of DH reported in Japan over the previous 10 years, including our cases, one case was associated with gluten‐sensitive enteropathy, four with malignant neoplasms, two with autoimmune systemic disorders and one with psoriasis. Although our cases were typical of DH in clinical, histopathological and IgA deposit features, they showed different human leukocyte antigen haplotypes, no gluten‐sensitive enteropathy and no DH‐specific IgA antibodies, including those to epidermal and tissue transglutaminases. These results suggest that studies of unique characteristics in Japanese DH patients should facilitate further understanding of pathogenesis in DH. 相似文献