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1.
Zootaxa ; 5360(3): 429-436, 2023 Oct 27.
Article in English | MEDLINE | ID: mdl-38220604

ABSTRACT

Two newharvestmenspecies,Phalangium nalanae sp. n. and Phalangium taylani sp. n., are described, diagnosed and illustrated based on male material from Hakkari Province, Turkey. Also, the differences between two new species and similar species of the genus Phalangium are discussed.


Subject(s)
Arachnida , Male , Animals , Turkey
2.
Int J Psychophysiol ; 112: 1-8, 2017 02.
Article in English | MEDLINE | ID: mdl-27871912

ABSTRACT

The modulation of delta oscillations (0.5-3.5Hz) by emotional stimuli is reported. Physical attributes such as color, brightness and spatial frequency of emotional visual stimuli have crucial effect on the perception of complex scene. Brightness is intimately related with emotional valence. Here we explored the effect of brightness on delta oscillatory responses upon presentation of pleasant, unpleasant and neutral pictures. We found that bright unpleasant pictures elicited lower amplitude of delta response than original unpleasant pictures. The electrophysiological finding of the study was in accordance with behavioral data. These results denoted the importance of delta responses on the examination of the association between perceptual and conceptual processes while in the question of brightness and emotion.


Subject(s)
Delta Rhythm/physiology , Emotions/physiology , Visual Perception/physiology , Adult , Female , Humans , Male , Young Adult
3.
Noro Psikiyatr Ars ; 52(2): 163-168, 2015 Jun.
Article in English | MEDLINE | ID: mdl-28360698

ABSTRACT

INTRODUCTION: The aim of this study was to evaluate cognitive impairment in patients having epilepsy or psychogenic nonepileptic seizures (PNESs) using selected neuropsychological tests at different time periods related to the seizure. METHODS: In this study, selected neurocognitive tests were administered to the patients. Within 24 h, the previously applied neurocognitive tests were repeated within 24 h following the observation of typical seizures when monitoring and normalizing electroencephalography (EEG) activity. Basal neurocognitive tests were also administered to the healthy control group, and repeat neurocognitive evaluation was performed within 24-96 h. RESULTS: The basal neurocognitive evaluation revealed that verbal learning and memory scores as well as Stroop test interference time were significantly lower in the PNES group compared with those in the controls. In the basal cognitive tests administered to the patients with epilepsy, verbal learning and memory scores, long-term memory, and total recognition test scores were significantly lower than those of the controls. Following the repeat cognitive tests, significant progress was found in the verbal categorical fluency score of the PNES group. No significant difference was determined in the epilepsy group. Significant contraction was determined in the Stroop interference time in the control group, but no similar change was recorded in the epilepsy or PNES groups. CONCLUSION: While memory problems seemed to be most prominent in the assessed patients with epilepsy, attention and executive function problems were more dominant in the patients with PNESs. These findings are probably related to numerous factors such duration of disease, mood disorders, and specific drug use. No deterioration in attention and executive functions was reported in the early post-seizure period in either patient group.

4.
Behav Neurol ; 2014: 268967, 2014.
Article in English | MEDLINE | ID: mdl-24825953

ABSTRACT

BACKGROUND: Event-related oscillations (ERO) may provide a useful tool for the identification of cognitive deficits in mild cognitive impairment (MCI) and Alzheimer's disease (AD). In the present study, we investigate peak-to-peak amplitude of auditory event-related delta oscillations of MCI subjects. METHOD: The study included twenty-two consecutive patients with MCI recruited in neurology clinic and 21 age- and education-matched normal elderly controls. A classical auditory oddball paradigm was used in the experiments. EEG was recorded from F3, Fz, F4, C3, Cz, C4, P3, Pz, P4, O1, Oz, and O2 locations. The maximum peak-to-peak amplitudes for each subject's averaged delta response (0.5-2.2 Hz) were measured. RESULTS: The amplitudes between groups differed significantly at the frontal and mid-centroparietal locations. ANOVA on delta responses revealed a significant effect for groups (F(1.41) = 4.84, P = 0.033), indicating a larger delta response for healthy controls than MCI subjects. Post hoc comparisons revealed that peak-to-peak delta response was significantly larger for healthy controls than for MCI over electrode sites F3, Fz, F4, Cz, C4, and Pz. DISCUSSION: Event-related delta frequency band seems to be the most affected oscillatory response in cognitive impairment due to AD. Therefore, it deserves to be investigated as a candidate electrophysiological biomarker in further studies.


Subject(s)
Auditory Cortex/physiopathology , Cognitive Dysfunction/physiopathology , Delta Rhythm/physiology , Evoked Potentials, Auditory/physiology , Aged , Aged, 80 and over , Electroencephalography , Female , Humans , Male , Middle Aged
5.
Neuroimage Clin ; 3: 39-46, 2013.
Article in English | MEDLINE | ID: mdl-24179847

ABSTRACT

The aim of the present study was to investigate the role of beta oscillatory responses upon cognitive load in healthy subjects and in subjects with mild cognitive impairment (MCI). The role of beta oscillations upon cognitive stimulation is least studied in comparison to other frequency bands. The study included 17 consecutive patients with MCI (mean age = 70.8 ± 5.6 years) according to Petersen's criteria, and 17 age- and education-matched normal elderly controls (mean age = 68.5 ± 5.5 years). The experiments used a visual oddball paradigm. EEG was recorded at 30 cortical locations. EEG-evoked power, inter-trial phase synchronization, and event-related beta responses filtered in 15-20 Hz were obtained in response to target and non-target stimuli for both groups of subjects. In healthy subjects, EEG-evoked beta power, inter-trial phase synchronization of beta responses and event-related filtered beta responses were significantly higher in responses to target than non-target stimuli (p < 0.05). In MCI patients, there were no differences in evoked beta power between target and non-target stimuli. Furthermore, upon presentation of visual oddball paradigm, occipital electrodes depict higher beta response in comparison to other electrode sites. The increased beta response upon presentation of target stimuli in healthy subjects implies that beta oscillations could shift the system to an attention state, and had important function in cognitive activity. This may, in future, open the way to consider beta activity as an important operator in brain cognitive processes.

6.
J Alzheimers Dis ; 37(4): 759-67, 2013.
Article in English | MEDLINE | ID: mdl-23948923

ABSTRACT

Mild cognitive impairment (MCI) is considered as a prodromal stage for Alzheimer's disease (AD) in the majority of cases. Event-related oscillations might be used for detection of cognitive deficits. Our group's earlier results showed diminished delta visual and auditory target oscillatory responses in AD, and we investigated whether this prevails for MCI. Eighteen MCI subjects and 18 age-matched healthy elderly controls were investigated. The maximum peak-to-peak amplitudes of oscillatory responses for each subject's averaged oscillatory target responses in delta, theta, and alpha frequency bands upon application of visual oddball paradigm were measured. Repeated measures of ANOVA was used to analyze four locations (frontal, central, parietal, occipital), at three coronal (left, midline, right) sites. Independent t tests were applied for post-hoc analyses. The oddball target delta response (0.5-3.0 Hz) was 26-32% lower in MCI than healthy controls over fronto-central-parietal regions [F(1.34) = 4.562, p = 0.04]. Without a group effect, theta oscillatory responses (4-7 Hz) showed significant differences in coronal electrodes indicating highest values over mid-electrode sites, and a anteriorposterior x coronal effect, being maximum at mid-central. Alpha frequency band analyses indicated no statistical differences. Peak-to-peak amplitudes of visual target delta oscillatory responses were lower in fronto-central-parietal regions in MCI than in healthy controls. This supports our earlier findings in AD, showing hypoactive delta fronto-central-parietal regions during cognitive tasks. These results indicate that event-related oscillations may detect early changes of brain dynamics in MCI, and deserves to be investigated as a candidate biomarker in further studies using multimodal techniques.


Subject(s)
Amnesia/physiopathology , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/physiopathology , Delta Rhythm/physiology , Down-Regulation/physiology , Photic Stimulation/methods , Visual Cortex/physiology , Aged , Amnesia/diagnosis , Female , Humans , Male , Middle Aged , Prospective Studies
7.
Aging Ment Health ; 15(3): 364-9, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21491221

ABSTRACT

Subjective memory complaint (SMC) is common among elderly people, and is thought to be part of mild cognitive impairment (MCI). We evaluated whether impaired digit span (IDS) in older people with SMC can predict wider impairment in future neuropsychological tests that correspond to MCI. After a mean of 6.6 years from the initial assessment, we reevaluated 16 subjects with SMC and normal digit span (NDS) scores (mean age 57.6 ± 8.1 years) and 28 subjects with SMC and IDS scores (mean age 59.7 ± 9.9 years). The IDS group showed wider cognitive decline in tests of short-term verbal memory and category verbal fluency compared to the NDS group. IDS scores indicate an earlier step for conversion of SMC to MCI.


Subject(s)
Cognition Disorders/psychology , Memory Disorders/psychology , Mental Recall , Neuropsychological Tests/statistics & numerical data , Adult , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/psychology , Cognition Disorders/diagnosis , Disease Progression , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Memory Disorders/diagnosis , Middle Aged , Predictive Value of Tests , Psychiatric Status Rating Scales/statistics & numerical data , Psychometrics , Wechsler Scales
8.
Biomacromolecules ; 12(3): 757-69, 2011 Mar 14.
Article in English | MEDLINE | ID: mdl-21280645

ABSTRACT

This study focuses on the solution antimicrobial effectiveness of a novel class of copolyoxetanes with quaternary ammonium and PEG-like side chains. A precursor P[(BBOx-m)(ME2Ox)] copolyoxetane was prepared by cationic ring-opening copolymerization of 3-((4-bromobutoxy)methyl)-3-methyloxetane (BBOx) and 3-((2-(2-methoxyethoxy)ethoxy)methyl)-3-methyloxetane (ME2Ox) to give random copolymers with 14-100 (m) mol % BBOx. Reaction of P[(BBOx-m)(ME2Ox)] with dodecyl dimethylamine gave the corresponding quaternary P[(C12-m)(ME2Ox)] polycation salts, designated C12-m, as viscous liquids in 100% yield. BBOx/ME2Ox and C12/ME2Ox ratios were obtained by (1)H NMR spectroscopy. C12-m molecular weights (M(n), 3.5-21.9 kDa) were obtained from (1)H NMR end group analysis. DSC studies up to 150 °C showed only thermal transitions between -69 and -34 °C assigned to T(g) values. Antibacterial activity for the C12-m copolyoxetanes was tested by determining minimum inhibitory concentrations (MICs) against Gram(+) Staphylococcus aureus and Gram(-) Escherichia coli and Pseudomonas aeruginosa . MIC decreased with increasing C12 mol percent, reaching a minimum in the range C12-43 to C12-60. Overall, the antimicrobial with consistently low MICs for the three tested pathogenic bacteria was C12-43: (bacteria, MIC, µg/mL) E. coli (6), S. aureus (5), and P. aeruginosa (33). For C12-43, minimum biocidal concentration (MBC) to reach 99.99% kill in 24 h required 1.5× MIC for S. aureus and 2× MIC for E. coli and P. aeruginosa . At 5× MIC against a challenge of 10(8) cfu/mL, C12-43 kills ≥99% S. aureus , E. coli , and P. aeruginosa within 1 h. C12-m copolyoxetane cytotoxicity toward human red blood cells was low, indicating good prospects for biocompatibility. The tunability of C12-m copolyoxetane compositions, effective antimicrobial behavior against Gram(+) and Gram(-) bacteria, and promising biocompatibility offer opportunities for further modification and potential applications as therapeutic agents.


Subject(s)
Anti-Infective Agents/chemistry , Biocompatible Materials/chemistry , Epoxy Compounds , Polymers , Propylene Glycols , Bacteria/drug effects , Microbial Sensitivity Tests , Solubility
9.
Langmuir ; 26(11): 9032-9, 2010 Jun 01.
Article in English | MEDLINE | ID: mdl-20334402

ABSTRACT

Prior research established that P[AB]-copolyoxetane polyurethanes with soft blocks having A = trifluoroethoxy (CF(3)CH(2)-O-CH(2)-, 3FOx) and B = dodecylammonium-butoxy (C12) are highly effective as polymer surface modifiers (PSMs). These PSMs displayed high contact antimicrobial efficiency against spray challenge that was attributed to surface concentration of quaternary charge. Herein, using a novel cell design and polymer coating process, streaming potential (SP) measurements are reported for estimating accessible surface charge density. Fused-silica capillaries were embedded in flat polypropylene sheets, and the inner capillary walls were coated with neat HMDI-BD(30)-P[(3FOx)(C12)-87:13-5100] (PU-1) and 1 wt % PU-1 in HMDI-BD(50)-PTMO-1000 (base polyurethane 2). Effects of annealing (60 degrees C) and electrolyte flow cycles on near-surface quaternary charge concentration were determined. Neat PU-1 had a constant SP that was cycle-independent and actually increased on annealing. As-cast 1 wt % PU-1 showed initial SPs about half those for neat PU-1, with substantial attenuation over 16 measurement cycles. SPs for annealed 1 wt % PU-1 displayed lower initial values that attenuated rapidly over multiple cycles. Zeta potentials and surface charge densities were calculated from SPs and discussed relative to contact antimicrobial properties. Tapping mode atomic force microscopy (TM-AFM) imaging was employed for investigation of 1 wt % PU-1 surface morphology. Microscale phase separation occurs on annealing 1 wt % PU-1 for 24 h at 60 degrees C. Surprisingly, phase separation was also observed after short immersion of 1 wt % PU-1 coatings in water. The morphological changes are correlated with instability of near-surface charge found by SP measurements. A model is proposed for near-surface spinodal decomposition of metastable as-cast 1 wt % PU-1. The formation of a fluorous modifier rich phase apparently sequesters near-surface quaternary charge and accounts for temporal instability of antimicrobial properties. The results are important in providing a facile method for screening polycation-based, contact antimicrobial coatings for accessible charge density and in assessing durability.


Subject(s)
Polyurethanes/chemistry , Surface Properties
10.
Int J Geriatr Psychiatry ; 24(11): 1242-50, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19337986

ABSTRACT

OBJECTIVE: To evaluate the reliability and validity of the revised Turkish version of Mini Mental State Examination (rMMSE-T) in educated and uneducated community-dwelling elderly, to re-organize the present Turkish version of MMSE and to determine cut-off point of the revised test. METHODS: This cross-sectional and analytical study involved totally 490 elderly subjects selected by cluster sampling method. Receiver operating characteristic (ROC) analysis, kappa analysis and Cronbach's alpha coefficients were used for statistical analysis. RESULTS: Areas under ROC curve in educated and uneducated elderly were found as 0.953 and 0.907. Cut-off point of 22/23 of rMMSE-T in educated elderly had the highest sensitivity (90.9), specificity (97.0) and positive likelihood ratio (30.3), whereas cut-off point of 18/19 of the test in uneducated elderly had the highest sensitivity (82.7), specificity (92.3) and positive likelihood ratio (10.7). The Cronbach's alpha values of the rMMSE-T for educated and uneducated elderly were higher than 0.7 (sign of good internal consistency of the test). A significant correlations between intrarater and interrater test-retest in educated elderly subjects were observed (0.966 (p = 0.000); 0.855 (p = 0.000), respectively), and also in uneducated elderly (0.988 (p = 0.000); 0.934 (p = 0.000), respectively). Kappa value of the test in educated and uneducated elderly showed a perfect agreement interraters (1.000) and a substantial agreement in intraraters (1.000, 0.784; 0.826, 0.656, respectively). CONCLUSION: rMMSE-T had a high reliability and validity. It will be more appropriate to use the revised test and the new cut-off point for the diagnosis and screening of dementia among community-dwelling Turkish elderly population.


Subject(s)
Dementia/diagnosis , Mental Status Schedule/standards , Aged , Aged, 80 and over , Area Under Curve , Cross-Sectional Studies , Educational Status , Female , Humans , Male , Reproducibility of Results , Turkey
11.
Neurocase ; 14(2): 147-50, 2008.
Article in English | MEDLINE | ID: mdl-18569739

ABSTRACT

Vitamin B12 deficiency can manifest with various neuropsychiatric symptoms. We report a case of an individual with vitamin B12 deficiency presenting with personality, emotional and behavioral changes. Neuropsychological tests revealed disproportionate disturbance of executive functions. Single photon emission tomography (Tc99m HMPAO) showed right fronto-temporo-parietal hypoperfusion. After vitamin B12 injections, the patient's executive and behavioral dysfunction disappeared and performance on neuropsychological tests was once again in the normal range.


Subject(s)
Vitamin B 12 Deficiency/drug therapy , Vitamin B 12 Deficiency/psychology , Vitamin B 12/therapeutic use , Affective Symptoms/diagnosis , Affective Symptoms/etiology , Behavioral Symptoms/diagnosis , Behavioral Symptoms/etiology , Humans , Male , Middle Aged , Neuropsychological Tests , Personality Disorders/diagnosis , Personality Disorders/etiology , Tomography, Emission-Computed, Single-Photon , Treatment Outcome , Vitamin B 12 Deficiency/diagnostic imaging
12.
Langmuir ; 24(11): 5816-24, 2008 Jun 03.
Article in English | MEDLINE | ID: mdl-18444667

ABSTRACT

This paper focuses on surface characterization of P[ AB] copolyoxetane soft block polyurethanes having either fluorous (3FOx, -CH2OCH 2CF3) or PEG-like (ME2Ox, -CH2(OCH2CH2) 2OCH3), A side chains and alkylammonium, B side chains. Physical surface characterization data were analyzed in light of the previously observed order of antimicrobial effectiveness for a set of four surface modifiers. Ample physical evidence for surface concentration of fluorous 2 wt % P[ AB]-polyurethane modifiers was obtained from XPS, contact angles, ATR-IR spectroscopy, and TM-AFM. In TM-AFM phase imaging, the most effective biocidal surface modifier, 2 wt % HMDI-BD(30)/P[(3FOx)(C12)-0.89:0.11]-PU, showed a nanoscale phase-separated structure consisting of 200 nm domains with background features about 10 times smaller. Despite similar surface characterization data, the 2 wt % fluorous C6 analog ranked third in contact biocidal effectiveness. Physical evidence for surface concentration of 2 wt % P[(ME2Ox)(C12)-0.86:0.14]-PU was modest, considering that antimicrobial effectiveness was second only to 2 wt % HMDI-BD(30)/P[(3FOx)(C12)-0.89:0.11]-PU. In this set of surface modifiers, nanoscale morphology is largely driven by the fluorous component, whereas antimicrobial effectiveness is more strongly influenced by alkylammonium chain length. The effect of alkylammonium side chain length on surface concentration and antimicrobial behavior is more pronounced for ME2Ox polyurethanes compared to the 3FOx analogs.


Subject(s)
Anti-Infective Agents/chemistry , Ethers, Cyclic/chemistry , Hydrocarbons, Fluorinated/chemistry , Polyurethanes/chemistry , Anti-Infective Agents/chemical synthesis , Polyurethanes/chemical synthesis , Surface Properties
13.
Langmuir ; 23(21): 10573-80, 2007 Oct 09.
Article in English | MEDLINE | ID: mdl-17824629

ABSTRACT

Polyurethanes containing poly(2-trifluoroethoxymethyl-2-methyl)-co-(2-bromomethyl-2-methyl)-1,3-propylene oxide (co-polyoxetane) soft blocks, P[3FOx:BrOx-m:n], were prepared and used (0.5-2 wt %) to modify the surface properties of a conventional polyurethane. The substrate polyurethane was composed of an isophorone diisocyanate/butanediol hard block and a polytetramethylene oxide soft block [IPDI/BD(50%)-PTMO(2000)]. A combination of tapping mode atomic force microscopy (TM-AFM), X-ray photoelectron spectroscopy (XPS), and dynamic contact angle (DCA) studies showed that the fluorous polyurethane surface modifiers confer surface properties similar to those of the parent at 0.5-1.0 wt %. The retention of initial wetting behavior in water was enhanced with higher ratios of 3FOx:BrOx that corresponds to increasing fluorous character. A semifluorinated chaperone is necessary to surface concentrate -CH2Br groups. Negligible Br was detected by XPS when the P[BrOx]-soft block polyurethane was used as a surface modifier (0.5%) and the wetting behavior was similar to that of the bulk polyurethane. Despite being hydrophobic (theta adv = 102 degrees) the P[BrOx]-soft block polyurethane is not a polymer surface modifier under the conditions described herein. The calculated solubility parameters for PTMO and P[BrOx], which are similar, support the notion of BrOx miscibility with the base polyurethane. The combination of miscibility of BrOx repeat units and lack of an end-group-like architecture minimizes BrOx surface concentration in the chosen bulk polyurethane.


Subject(s)
Ethers, Cyclic/chemistry , Polyurethanes/chemistry , Microscopy, Atomic Force , Spectrum Analysis/methods , X-Rays
14.
Langmuir ; 23(9): 4719-23, 2007 Apr 24.
Article in English | MEDLINE | ID: mdl-17388618

ABSTRACT

Contact antimicrobial coatings with poly(alkylammonium) compositions have been a subject of increasing interest in part because of the contribution of biocide release coatings to antibiotic resistance. Herein, a concept for antimicrobial coatings is developed on the basis of the thermodynamically driven surface concentration of soft block side chains. The concept incorporates structural and compositional guidance from naturally occurring antimicrobial proteins and achieves compositional economy via a polymer-surface modifier (PSM). To implement this concept, polyurethanes were prepared having random copolymer 1,3-propylene oxide soft blocks with alkylammonium and either trifluoroethoxy or PEGlyted side chains. Six carbon (C6) and twelve carbon (C12) alkylammonium chain lengths were used. The PSMs were first tested as 100% coatings and were highly effective against aerosol challenges of Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). To evaluate the surface concentration, solutions containing 2 wt % PSM with a conventional polyurethane were evaporatively coated onto glass slides. These 2% PSM coatings were tested against aerosol challenges of Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria (107 CFU/mL/30 min). A copolymer soft block containing trifluorethoxy (89 mol %) and C-12 alkylammonium (11 mol %) side chains gave the highest biocidal effectiveness in 30 min: 2 wt %, Gram(+/-) bacteria, 100% kill, and 3.6-4.4 log reduction. A zone of inhibition test showed no biocide release for PSMs and PSM-modified compositions. Characteristics that contribute to concept validation include good hard block/soft block phase separation, a cation/co-repeat group ratio mimicking natural biocidal proteins, a semifluorinated "chaperone" aiding in alkylammonium surface concentration, and a low Tg for the alkylammonium soft block.


Subject(s)
Anti-Bacterial Agents/chemistry , Polymers/chemistry , Quaternary Ammonium Compounds/chemistry , Anti-Bacterial Agents/pharmacology , Escherichia coli/drug effects , Microbial Sensitivity Tests , Molecular Structure , Polymers/pharmacology , Pseudomonas aeruginosa/drug effects , Quaternary Ammonium Compounds/pharmacology , Sensitivity and Specificity , Staphylococcus aureus/drug effects , Surface Properties
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