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Abdulkadir Koçer Emel Koçer Halit Beşir Süber Dikici Füsun Domaç Nurten Ercan 《Medical hypotheses》2013
Background
Decreased posterior cerebral circulation has been observed in patients with vertebrobasilar insufficiency (VBI). Reduced cerebral perfusion may have an impact on mental performance as measured by the Benton Facial Recognition Test (BFRT). We evaluated the usefulness of BFRT in identifying cognitive decline in patients with VBI by correlating test performance with total blood flow in the vertebrobasilar system and other variables such as educational level and gender.Materials and methods
Thirty-three participants without dementia (mini-mental state examination; MMSE >27) and cranial magnetic resonance imaging abnormality, but with atherosclerotic risk factors were involved in the study. Nineteen subjects had a total vertebrobasilar flow volume less than 200 ml/min (Group I), and 14 subjects had a flow volume more than 200 ml/min (Group II).Results
The groups were similar in regard to gender, age, and educational level. BFRT results were 19.53 ± 3.12 and 22.36 ± 2.73 for Groups I and II, respectively (p = 0.01). The educational level was the main factor affecting the BFRT score in Group I (p = 0.04).Discussion
BFRT is clearly impaired in VBI as measured by Doppler ultrasound examination. We concluded that the test appears to adequately distinguish cognitive levels between VBI and other patients. Additionally, our results suggest that education is associated with BFRT results, and for normative purposes, gender consideration is unnecessary. Further studies are needed to investigate the association between VBI and memory dysfunction in early dementia. 相似文献33.
Francisco Ferro de Beça Cátia Rasteiro Alda Correia Susy Costa Isabel Amendoeira 《Annals of diagnostic pathology》2013,17(5):434-436
Core-needle biopsy (CNB) of breast lesions can be classified into 5 categories according to lesion type and associated risk of malignancy. B3 category (lesion of uncertain malignant potential) constitutes a challenging problem in clinical decision, with most ending in excisional biopsy. Therefore, the aim of this study was to establish the incidence of malignancy on excision biopsy of B3 lesions and assess if subclassification (in B3a and B3b categories) according to the presence of atypia in otherwise B3 lesions better predicts malignancy on excision. Forty-eight cases with diagnosis of B3 lesion on CNB and matched surgical excision specimen were included to evaluate the positive predictive value (PPV) and odds for malignancy in CNB. All cases were further subclassified into B3a and B3b categories. B3 category lesions had an overall PPV for malignancy of 12.5% and significant low odds of malignancy of 0.14. When subclassified, B3b (lesions with atypia) demonstrated a higher PPV for malignancy (36.36%) with a nonsignificant odds. Inversely, B3a (lesions without atypia) demonstrated a PPV for malignancy of only 5.41% and a significant low odds of malignancy of only 0.06. The described low rate of malignancy in some of B3 lesions additionally reinforces the practice of avoiding surgical excision in selected patients and provides data that additionally support B3 lesion subclassification according to the presence of atypia. Subclassification of B3 category can further refine the current classification of associated risk of malignancy with possible implications in clinical management. 相似文献
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Sabol F Jakubová M Kolesár A Stančák B Beňa M Podracký J Podracká L Cadník P Spatenka J 《Vnitr?ní lékar?ství》2012,58(6):494-498
Prosthetic infective endocarditis is a possible complication of implantation of a prosthetic cardiac valve. Without early and effective treatment, it can have fatal consequences. One treatment option is use of an allogeneic cryopreserved homograft. This case report presents a 21-year old patient after kidney transplantation due to hereditary nephrotic syndrome and aortic valve replacement with aortic conduits. After fever was noted in the patient, prosthetic infective endocarditis was diagnosed by echocardiography and also confirmed by CT-3D examination. The cryopreserved aortic homograft was implanted at the Department of Cardiac Surgery. This along with additional conservative management effectively treated the infection. Based on literature data and our own experience, we believe that the treatment of prosthetic endocarditis after aortic valve replacement with cryopreserved homograft can be a method of choice. 相似文献
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Pınar Güzel Özdemir Yavuz Selvi Halil Özkol Adem Aydın Yasin Tülüce Murat Boysan Lütfullah Beşiroğlu 《Psychiatry research》2013
Shift work influences health, performance, activity, and social relationships, and it causes impairment in cognitive functions. In this study, we investigated the effects of shift work on participants' cognitive functions in terms of memory, attention, and learning, and we measured the effects on oxidative stress. Additionally, we investigated whether there were significant relationships between cognitive functions and whole blood oxidant/antioxidant status of participants. A total of 90 health care workers participated in the study, of whom 45 subjects were night-shift workers. Neuropsychological tests were administered to the participants to assess cognitive function, and blood samples were taken to detect total antioxidant capacity and total oxidant status at 08:00. Differences in anxiety, depression, and chronotype characteristics between shift work groups were not significant. Shift workers achieved significantly lower scores on verbal memory, attention–concentration, and the digit span forward sub-scales of the Wechsler Memory Scale-Revised (WMS-R), as well as on the immediate memory and total learning sub-scales of the Auditory Verbal Learning Test (AVLT). Oxidative stress parameters were significantly associated with some types of cognitive function, including attention–concentration, recognition, and long-term memory. These findings suggest that night shift work may result in significantly poorer cognitive performance, particularly working memory. 相似文献
39.
Validation of flavonoids as potential dipeptidyl peptidase III inhibitors: Experimental and computational approach
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Dejan Agić Hrvoje Brkić Sanja Tomić Zrinka Karačić Marija Špoljarević Miroslav Lisjak Drago Bešlo Marija Abramić 《Chemical biology & drug design》2017,89(4):619-627
Fifteen flavonoids were studied for their inhibitory activity against human dipeptidyl peptidase III (hDPP III) combining an in vitro assay with an in silico molecular modeling study. All analyzed flavonoids showed inhibitory effects against hDPP III with the IC50 values ranging from 22.0 to 437.2 μm . Our 3D QSAR studies indicate that the presence of hydrophilic regions at a flavonoid molecule increases its inhibitory activity, while the higher percentage of hydrophobic surfaces has negative impact on enzyme inhibition. Furthermore, molecular dynamics (MD) simulations of the complex of hDPP III with one of the most potent inhibitors, luteolin, were performed, and binding mode analysis revealed that the 3′ and 4′ hydroxyl group on B‐ring as well as 5 and 7 hydroxyl group on A‐ring helps luteolin to interact with the Asn391, Asn406, Tyr417, His450, Glu451, Val447, Glu512, Asn545, Gln566, and Arg572 residues. The MD results clearly provide valuable information explaining the importance of flavonoid hydroxyl groups in the mechanism for the binding pattern at the active site of hDPP III. 相似文献
40.
Beáta Flachner Tünde Tömöri István Hajdú Krisztina Dobi Zsolt Lőrincz Sándor Cseh György Dormán 《Medicinal chemistry research》2014,23(3):1234-1247
Target-focused libraries can be rapidly selected by 2D virtual screening methods from multimillion compounds’ databases if structures of active compounds are available. In the present study, a multi-step virtual and in vitro screening cascade is used to select melanin-concentrating hormone receptor-1 antagonists. The 2D similarity search combined with physico-chemical parameter filtering is suitable for selecting candidates from multimillion compounds’ repository. The seeds of the first round of virtual screening were collected from literature commercial databases, whereas the seeds of the second round were the hits the first round of biological testing In vitro screening underlined the efficiency of our approach, as in the second screening round the hit rate (8.6 %) significantly improved compared to the first round (1.9 %), applying a strict requirement for hit selection, and also this cascade-like screening method was appropriate for selecting several compounds reaching efficacies even below 10 nM. 相似文献