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31.
Large‐scale brain network abnormalities in Huntington's disease revealed by structural covariance 下载免费PDF全文
Lora Minkova Simon B. Eickhoff Ahmed Abdulkadir Christoph P. Kaller Jessica Peter Elisa Scheller Jacob Lahr Raymund A. Roos Alexandra Durr Blair R. Leavitt Sarah J. Tabrizi Stefan Klöppel TRACK‐HD Investigators 《Human brain mapping》2016,37(1):67-80
Huntington's disease (HD) is a progressive neurodegenerative disorder that can be diagnosed with certainty decades before symptom onset. Studies using structural MRI have identified grey matter (GM) loss predominantly in the striatum, but also involving various cortical areas. So far, voxel‐based morphometric studies have examined each brain region in isolation and are thus unable to assess the changes in the interrelation of brain regions. Here, we examined the structural covariance in GM volumes in pre‐specified motor, working memory, cognitive flexibility, and social‐affective networks in 99 patients with manifest HD (mHD), 106 presymptomatic gene mutation carriers (pre‐HD), and 108 healthy controls (HC). After correction for global differences in brain volume, we found that increased GM volume in one region was associated with increased GM volume in another. When statistically comparing the groups, no differences between HC and pre‐HD were observed, but increased positive correlations were evident for mHD, relative to pre‐HD and HC. These findings could be explained by a HD‐related neuronal loss heterogeneously affecting the examined network at the pre‐HD stage, which starts to dominate structural covariance globally at the manifest stage. Follow‐up analyses identified structural connections between frontoparietal motor regions to be linearly modified by disease burden score (DBS). Moderator effects of disease load burden became significant at a DBS level typically associated with the onset of unequivocal HD motor signs. Together with existing findings from functional connectivity analyses, our data indicates a critical role of these frontoparietal regions for the onset of HD motor signs. Hum Brain Mapp 37:67–80, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
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Kırış A Erem C Kırış G Koçak M Gedikli O Nuhoğlu I Kutlu M Kaplan T Gökçe M Celik S 《Endocrine》2010,38(2):283-288
Hyperthyroidism causes a variety of adverse effects on the cardiovascular system. Left ventricular (LV) asynchrony is defined as loss of the simultaneous peak contraction of corresponding cardiac segments. The aim of this study was to assess systolic asynchrony in patients with overt hyperthyroidism. Asynchrony was evaluated in 27 patients with overt hyperthyroidism and 21 controls. All the patients and controls were subjected to a tissue synchronization imaging (TSI). The time to regional peak systolic tissue velocity (Ts) in LV by the six-basal-six-mid-segmental model was measured on ejection phase TSI images and four TSI parameters of systolic asynchrony were computed. All TSI parameters of LV asynchrony increased in hyperthyroid patients compared to controls: the standard deviation (SD) of the 12 LV segments Ts (35.7±14.4 vs 20.1±10.1, P<0.0001); the maximal difference in Ts between any 2 of the 12 LV segments (111.9±40.7 vs 65.9±30.7, P<0.0001); the SD of the 6 basal LV segments (31.2±18.2 vs 16.8±9.7, P=0.01); and the maximal difference in Ts between any 2 of the 6 basal LV segments (76.6±42.0 vs 44.4±25.7, P=0.005). Patients with overt hyperthyroidism present evidence of LV asynchrony by TSI. 相似文献
34.
Kocer A Ilhan A Ince N Bilge C 《Progress in neuro-psychopharmacology & biological psychiatry》2005,29(6):983-988
We investigated the influence of early awakening and related factors on onset of cerebrovascular disease (CVD). Totally 1199 stroke patients, in whom the onset time was known, at 3 reference hospitals were included in this study. The effects of demographic, medical, and pathophysiological factors on the circadian pattern of an unselected series of patients with ischemic stroke were analyzed. Nine-hundred seventeen CVD patients with cerebral infarction (CI), 240 patients with intracerebral hemorrhage (CH), and 42 patients with subarachnoid hemorrhage (SAH) were identified. The greatest portion of strokes (32.5%) occurred between 03:00 and 06:00 a.m. Nearly one half of the strokes in this series occurred in the very early- to mid-morning hours. This analysis of strokes provides strong evidence with a higher risk in the early morning hours (03:00 a.m. to 06:00 a.m.), and lower risk during the night time period (21:00 p.m. to midnight). Approximately 1 of every 3 strokes (1 of 3 ischemic strokes, 1 of 6 hemorrhagic strokes, and 1 of 8 subarachnoid hemorrhages) is attributable to the early morning excess. This difference tried to be explained by three ways: cold weather, religious factors, and physiological mechanisms. 相似文献
35.
Genc A Taneli F Yilmaz O Turkdogan P Arslan OA Sencan A Taneli C 《Scandinavian journal of urology and nephrology》2004,38(5):401-404
OBJECTIVE: In two-stage orchidopexy, adhesions formed after the first stage usually cause difficulty during the second operation and may even lead to injury to the testis itself or to the spermatic cord. We investigated whether the use of adhesion-preventing barriers in the abdominal or pelvic region during surgery could lessen adhesions formed during two-stage orchidopexy and thus ease dissection. MATERIAL AND METHODS: The study subjects comprised 21 male, albino, 30-day-old Wistar rats that were divided into three equal groups. In Group 1, the right testes were enveloped in adhesion barriers after dissection and sutured to the inguinal canal. In Group 2, the right testes were sutured to the inguinal canal without the barriers. In Group 3 (sham-operated group), all testes were dissected but no suturing was performed. Rats were sacrificed after 21 days and the ipsilateral testes were harvested. RESULTS: Dissection of barrier-enveloped testes was relatively easy; however, no significant (p < 0.535) difference was seen in adhesion scores between Groups 1 and 2. Total tissue collagen was estimated by means of the hydroxyproline content. Tissue hydroxyproline levels were 16.04 +/- 8.58, 13.20 +/- 6.34 and 14.71 +/- 5.51 microg/mg wet tissue in Groups 1-3, respectively and these differences were not significant. The histopathologic evaluation revealed significant differences only in the thickness of the tunica albuginea in Groups 1 and 2 (110.0 +/- 30.0 vs 77.1 +/- 21.3 microm, respectively; p < 0.038). CONCLUSION: The adhesion scores and the biochemical and histopathological examinations showed that an adhesion barrier is not beneficial in two-stage orchidopexy. 相似文献
36.
Exercise induces hypoglycemia in rats with islet transplantation 总被引:2,自引:0,他引:2
Omer A Duvivier-Kali VF Aschenbach W Tchipashvili V Goodyear LJ Weir GC 《Diabetes》2004,53(2):360-365
Recently, islet transplantation in patients with type 1 diabetes has had greater success than in the past, but the important question of whether the kinetics of islet secretion are able to accommodate the metabolic demands of special conditions such as exercise remains unanswered. Syngeneic rat islets (4,000 islet equivalents/rat) were transplanted into the liver, kidney, and peritoneal cavity (encapsulated or nonencapsulated) of rats with streptozocin-induced diabetes. Normoglycemic transplanted rats and age-matched controls were subjected to 30 min of moderate exercise on a treadmill 5 weeks after transplantation. Although control rats maintained near normoglycemia during and after exercise, the rats with islet transplants had significantly lower blood glucose levels. For the rats with islets in the liver, increased C-peptide levels were found at 30 min (790 +/- 125 and 1,450 +/- 250 pmol/l at 0 and 30 min, respectively; P < 0.01), whereas a decrease was found in controls and in rats with islets transplanted into the peritoneal cavity or under the kidney capsule. Moreover, increased glucagon levels were found after exercise in the rats with islets transplanted into the liver (62 +/- 6, 165 +/- 29, 155 +/- 27, and 97 +/- 13 pg/ml at 0, 30, 60, and 90 min, respectively; P < 0.05), whereas no changes in glucagon levels were observed in controls. In conclusion, moderate exercise caused hypoglycemia in rats with islet transplants in different sites including liver, kidney, and peritoneal cavity. C-peptide and glucagon responses to exercise were very different in rats with transplanted islets compared with controls. This islet dysfunction led to exercise-induced hypoglycemia. 相似文献
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38.
?ahin??obanEmail author Osman?Yüksel Seyfettin?K?klü Koray?Ceyhan Meltem?Baykara Abdulkadir?D?kmeci 《BMC cancer》2004,4(1):89
Background
Hepatocellular carcinoma is a common malignancy for which chronic hepatitis B infection has been defined as the most common etiologic factor. The most frequent metastatic sites are the lung, bone, lymphatics, and brain, respectively. Metastases to the chest wall have been reported only rarely.Case presentation
We report a patient with hepatocellular carcinoma who presented with an isolated metastatic mass on the left anterolateral chest wall in the axillary region.Conclusions
Metastasis of HCC should be included in the differential diagnosis of rapidly growing lesions in unusual localizations, particularly in patients with chronic liver disease even if a primary tumor can not be radiologically identified.39.
Onal C Yakinci C Kocak A Erguvan R Tekiner A Kutlu R Ozcan C Gul A 《Pediatric neurosurgery》2002,36(2):90-95
Spinal cord injury with or without trauma has been reported in the perinatal period. The prognosis depends primarily on diagnosis of the level, extent and nature of the lesion, established by correlations between clinical, imaging and electrophysiological data. A 25-day-old boy with normal birth weight delivered at term by cesarean section was transferred to In?nü University Turgut Ozal Medical Center because of respiratory distress and brachial diplegia. A suspicious medullary lesion on cervical computerized tomography was confirmed as an intramedullary lesion extending from C3 to D1 on magnetic resonance imaging (MRI). Emergent surgery consisting of exposure of the lesion site and interlaminar direct puncture of the lesion under fluoroscopy revealed that the pathology was an intramedullary hematoma. The partial evacuation of the lesion with direct puncture, the patient's neurological improvement and close follow-up of the patient with ultrasonography, electrophysiology and MRI are discussed in the light of recent literature. 相似文献
40.
OBJECTIVE: To study basal C-peptide (BCP) and postglucagon C-peptide (PGCP) levels in Ethiopians with diabetes. RESEARCH DESIGN AND METHODS: A total of 56 subjects with type 1 diabetes, 97 subjects with type 2 diabetes, and 50 control subjects were recruited from a hospital in Ethiopia. BCP was determined in all subjects and PGCP in 86 subjects. RESULTS: Mean (+/- SEM) BCP, PGCP, and the increment after glucagon in type 1 diabetic subjects (0.14 +/- 0.04, 0.22 +/- 0.11, and 0.08 +/- 0.05 nmol/l, respectively) were lower (P < 0.001) than those in type 2 diabetic subjects (0.66 +/- 0.04, 1.25 +/- 0.10, and 0.56 +/- 0.06 nmol/l, respectively) or control subjects (0.54 +/- 0.04, 1.52 +/- 0.26, and 1.11 +/- 0.24 nmol/l, respectively). The mean BCP level was higher in type 2 diabetic subjects than control subjects (P=0.015), whereas the mean increment was lower (P=0.005). Insulin-treated type 2 diabetic subjects, compared with non-insulin-treated type 2 diabetic subjects, had lower mean BCP (0.55 +/- 0.08 nmol/l [n=37] vs. 0.73 +/- 0.04 [n=60], P=0.001), lower PGCP (0.97 +/- 0.20 nmol/l [n=18] vs. 1.40 +/- 0.11 [n=35], P=0.010), and a lower C-peptide increment (0.34 +/- 0.06 [n=18] vs. 0.67 +/- 0.07 nmol/l [n=35], P=0.003). In both the type 1 and type 2 diabetic groups, those with BCP levels <0.2 nmol/l had lower BMI than those with higher BCP levels (P=0.023 and P < 0.001, respectively). CONCLUSIONS: Combined with clinical criteria, C-peptide levels are good discriminators between type 1 and type 2 diabetes in Ethiopians and may also be useful in identifying subjects with type 2 diabetes who require insulin therapy. There is a subgroup of type 2 diabetic subjects with features of type 1 diabetes. 相似文献