Dual Nanofriction Force Microscopy/Fluorescence Microscopy Imaging Reveals the Enhanced Force Sensitivity of Polydiacetylene by pH and NaCl.

Polydiacetylene (PDA) is a popular mechanochromic material often used in biosensing. The effect of its headgroup-headgroup interactions on thermochromism such as pH or salt concentration dependency has been extensively studied before; however, their effect on mechanochromism at the nanoscale is left unstudied. In this work, nanofriction force microscopy and fluorescence microscopy were combined to study the effect of pH and ionic strength on the polydiacetylene (PDA) force sensitivity at the nanoscale. We found that the increase in pH from 5.7 to 8.2 caused an 8-fold enhancement in force sensitivity. The elevation of NaCl concentration from 10 to 200 mM also made the PDA 5 times more force-sensitive. These results suggest that the PDA force sensitivity at the nanoscale can be conveniently enhanced by "pre-stimulation" with pH or ionic strength.

Replacement of the lower eyelid after tumor removal / Az alsó szemhéj pótlása tumoreltávolítás után

Összefoglaló. Bevezetés: A tumoreltávolítás miatt végzett teljes alsószemhéj-pótlás összetett feladat lehet. A rekonstrukció célja a kielégíto funkcionális és kozmetikai eredmény elérése. Célkituzés: A módosított Fricke-lebennyel végzett rekonstrukció tapasztalatainak bemutatása az alsó szemhéj teljes hiánya esetén. Módszer: 2010. január és 2020. december között 7 beteg esetében tumoreltávolítás után végeztünk alsószemhéj-rekonstrukciót módosított Fricke-lebennyel. A lebeny képzése a halántéktájon történt. A betegek átlagéletkora 72,8 év volt. A szövettani eredmény minden esetben basocellularis carcinoma volt. Az átlagos követési ido 1,9 év volt. Eredmények: Minden esetben jó funkcionális és esztétikai eredményt értünk el. Lebenynecrosist, sebelégtelenséget nem tapasztaltunk. A korai posztoperatív szakban átmeneti conjunctiva- és szemhéjoedema volt tapasztalható. 3 beteg esetében könnyezés, 1 beteg esetében érinto szorök okozta szemszúródást észleltünk. Recidíva nem alakult ki a követési ido alatt. Következtetés: Tapasztalataink szerint a módosított Fricke-lebeny kiváló funkcionális és esztétikai eredményt ad a tumoreltávolítás utáni teljes alsószemhéj-rekonstrukcióban. Orv Hetil. 2021; 162(29): 1180-1184. INTRODUCTION: The full-thickness lower eyelid reconstruction after tumor removal can be a complex challenge. The aim of reconstruction is to reach an appropriate functional and cosmetic result. OBJECTIVE: To present the retrospective analysis of the reconstruction's experience with the use of Fricke's flap in the case of full-thickness lower eyelid defect. METHOD: Between January 2010 and December 2020, in the case of 7 patient's after tumor excision on lower eyelid, reconstruction was performed with a modified Fricke's flap. The Fricke's flap was fashioned in the temple region. The patients' average age was 72.8 years. The histological result was basocellular carcinoma in every case. The average follow-up period was 1.9 years. RESULTS: In all cases, good functional and cosmetic result was detected. There were not any flap necrosis and wound dehiscence. In the early postoperative period, temporary edema of the eyelid and conjunctiva was detected. Epiphora occurred in the case of 3 patients and we observed eye irritation caused by skin hair in the case of 1 patient. Tumor recurrence was not detected during the follow-up period. CONCLUSION: In our experience, the modified Fricke's flap has excellent functional and aesthetic results in the reconstruction after tumor removal on the lower eyelid. Orv Hetil. 2021; 162(29): 1180-1184.

Quantitative and Anisotropic Mechanochromism of Polydiacetylene at Nanoscale.

Quantitative and anisotropic mechanochromism of polydiacetylene over nanoscale distances remains unaddressed even after 50 years of extensive research. This is because its anisotropic structure on substrates necessitates the application of both vertical and lateral forces (shear forces) to characterize it, whereas atomic force microscopy, which is the usual technique used to investigate nanoscale forces, is only capable of quantifying vertical forces. In this study, we address this lacuna by utilizing quantitative friction force microscopy that measures lateral forces. Our data confirm that polydiacetylene reacts only to lateral forces, F//, and disprove the previously claimed hypothesis that the edges of the polymer crystals exhibit higher force sensitivity than the rest of the crystal. In addition, we report a correlation between mechanochromism and thermochromism, which can be attributed to the fact that both work and heat are different means of providing the same transition energy.

Direction Dependent Electrical Conductivity of Polymer/Carbon Filler Composites.

The method of measuring electrical volume resistivity in different directions was applied to characterize the filler orientation in melt mixed polymer composites containing different carbon fillers. For this purpose, various kinds of fillers with different geometries and aspect ratios were selected, namely carbon black (CB), graphite (G) and expanded graphite (EG), branched multiwalled carbon nanotubes (b-MWCNTs), non-branched multiwalled carbon nanotubes (MWCNTs), and single-walled carbon nanotubes (SWCNTs). As it is well known that the shaping process also plays an important role in the achieved electrical properties, this study compares results for compression molded plates with random filler orientations in the plane as well as extruded films, which have, moreover, conductivity differences between extrusion direction and perpendicular to the plane. Additionally, the polymer matrix type (poly (vinylidene fluoride) (PVDF), acrylonitrile butadiene styrene (ABS), polyamide 6 (PA6)) and filler concentration were varied. For the electrical measurements, a device able to measure the electrical conductivity in two directions was developed and constructed. The filler orientation was analyzed using the ratio σin/th calculated as in-plane conductivity σin-plane (σin) divided by through-plane conductivity σthrough-plane (σth). The ratio σin/th is expected to increase with more pronounced filler orientation in the processing direction. In the extruded films, alignment within the plane was assigned by dividing the in-plane conductivity in the extrusion direction (x) by the in-plane conductivity perpendicular to the extrusion direction (y). The conductivity ratios depend on filler type and concentration and are higher the higher the filler aspect ratio and the closer the filler content is to the percolation concentration.

[Source-monitoring deficits in schizophrenia: review and pharmacotherapeutic implications]. / A forrásmonitorozás zavarai szkizofréniában: áttekintés és farmakoterápiás következtetések.

The disturbance of source-monitoring is one of the various impairments in cognitive functioning observed in schizophrenic patients. The process of source-monitoring allows individuals to distinguish self generated thoughts and behaviours from those generated by others. The aim of the present study is to review the general psychological definition of source memory and source-monitoring and its neurological basis as well as the models for explanation of source-monitoring deficits. The relationship between source-monitoring-deficits and psychopathological symptoms as well as the effect of antipsychotic treatment on source-monitoring disturbances are introduced. There is evidence suggesting, that a selective source-monitoring deficit is in the occurrence of auditory hallucinations. The disturbance of prospective memory may influence unfavorably the compliance. Administration of antipsychotics in general can improve source-monitoring deficits. The neuropsychiatric perspective provides a more accurate and comprehensive understanding of schizophrenia.

[Insight into illness and compliance in schizophrenic disorders]. / Betegségbelátás és terápiás együttmuökdés szkizofrén kórképekben.

Poor insight into illness is a characteristic and common phenomenon in schizophrenic disorders. Lack of insight may lead to poor clinical outcome, thus, research focused on this phenomenon could help develop effective treatment strategies. The relationship between compliance with treatment and insight is complex and it may be influenced mostly by specific components of insight. The aim of the present study was to review the current definitions of insight, the tools and questionnaires used for its measurement, as well as the relationship between insight and psychopathological symptoms. Three theoretical models developed for the explanation of impaired insight are described; the Psychological Defence Model, the Cognitive Deficit Model, and the Neuropsychological Deficit Model. The neurocognitive bases of impaired insight is given special attention in this article. Administration of second generation antipsychotics and psychosocial interventions (psychoeducation with problem solving procedures and motivating techniques) can improve insight, and enhance compliance with treatment, thus, optimizing long-term therapeutic outcome for schizophrenia patients.

[The use of RBANS test (Repeatable Battery for the Assessment of Neuropsychological Status) in neurocognitive testing of patients suffering from schizophrenia and dementia]. / Az RBANS teszt alkalmazása schizophren es dementiában szenvedó betegek neurokognitív vizsgálatában.

INTRODUCTION: The purpose of our study was to find out whether the Hungarian adaptation of the RBANS (Repeatable Battery for the Assessment of Neuropsychological Status), a brief neurocognitive screening test, is appropriate for the differentiation of healthy and non-healthy subject groups, or for the detection of differences between the cognitive performance of patient groups. PATIENTS AND METHODS: The test battery was administrated to 38 healthy subjects, 69 schizophrenic patients, and 18 patients suffering from dementia (10 probable Alzheimer-type and eight vascular dementia). RESULTS: There was a significant decrease of performance in all patient groups compared to the healthy group. In the schizophrenic group, the test indicated a deterioration of functioning in all cognitive areas. The patient group with Alzheimer-type dementia performed only slightly better than the schizophrenic group, because the fall of performance was not significant only one of the cognitive areas (in the visuo-spatial tasks) when compared to the healthy group. There was no difference between the performance of patients with vascular dementia and that of healthy subjects in direct memory, verbal and visuo-spatial tasks. The test results indicated an even deterioration of cognitive areas in patients with Alzheimer-type dementia. As for the vascular dementia group, the most vulnerable area proved to be that of attention, while their verbal functions were relatively spared. The deterioration in other cognitive functions shown by schizophrenic subjects was more moderate, but still significant. A comparison of the RBANS scores of the schizophrenic patients in our study and the result of an American study was also carried out. The global indeces showed no difference; only the pattern of the sub-scales was a little different. CONCLUSION: The Hungarian version of the RBANS seems approprite for the differentiation of healthy and deteriorated cognitive performance in a Hungarian patient population.