Proton–proton collisions
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Nitrile imines produced by photodissociation of 2,5-diaryltetrazoles undergo cross-linking reactions with amide groups in peptide-tetrazole (tet-peptide) conjugates and a tet-peptide-dinucleotide complex. Tetrazole photodissociation in gas-phase ions is efficient, achieving ca. 50% conversion with 2 laser pulses at 250 nm. The formation of cross-links was detected by CID-MS3 that showed structure-significant dissociations by loss of side-chain groups and internal peptide segments. The structure and composition of cross-linking products were established by a combination of UV-vis action spectroscopy and cyclic ion mobility mass spectrometry (c-IMS). The experimental absorption bands were found to match the bands calculated for vibronic absorption spectra of nitrile imines and cross-linked hydrazone isomers. The calculated collision cross sections (CCSth) for these ions were related to the matching experimental CCSexp from multipass c-IMS measurements. Loss of N2 from tet-peptide conjugates was calculated to be a mildly endothermic reaction with ΔH0 = 80 kJ mol-1 in the gas phase. The excess energy in the photolytically formed nitrile imine is thought to drive endothermic proton transfer, followed by exothermic cyclization to a sterically accessible peptide amide group. The exothermic nitrile imine reaction with peptide amides is promoted by proton transfer and may involve an initial [3 + 2] cycloaddition followed by cleavage of the oxadiazole intermediate. Nucleophilic groups, such as cysteine thiol, did not compete with the amide cyclization. Nitrile imine cross-linking to 2'-deoxycytidylguanosine was found to be >80% efficient and highly specific in targeting guanine. The further potential for exploring nitrile-imine cross-linking for biomolecular structure analysis is discussed.
An alarming number of traffic-related deaths occur each year on European roads alone. Figures reveal that the vast majority of road-traffic accidents are caused by drivers themselves, and so further improvements in road safety require developments in driver training and rehabilitation. This study evaluated a novel approach to driver rehabilitation-specifically, empathy induction as a means of changing attitudes towards risky driving. To assess the effectiveness of this method, the present study employed functional magnetic resonance imaging (fMRI) to compare brain function before and after a short program of empathy induction in 27 drivers whose licenses had been revoked after serious traffic offences (rehabilitated drivers [RDs]). In an extension of our previous research, we first assessed whether neural responses to empathy-eliciting social stimuli changed in these RDs. In order to isolate the neurophysiological effects of empathy induction from any other potential influences, we compared these RDs to a sample of 27 age-, handedness- and driving experience-matched control drivers (CDs) who had no exposure to the program. We then performed dual-fMRI "hyperscanning" to evaluate whether empathy induction changed brain responses during real-world social interactions among drivers; namely, during co-operative and/or competitive exchanges. Our data reveal that RDs exhibited weaker brain responses to socio-emotional stimuli compared with CDs prior to the program, but this difference was reversed after empathy induction. Moreover, we observed differences between pre- and post-program assessments in patterns of brain responses in RDs elicited during competitive social exchanges, which we interpret to reflect a change in their proclivity to react to the perceived wrong-doing of other road users. Together, these findings suggest that empathy induction is an effective form of driver rehabilitation, and the utility of neuroscientific techniques for evaluating and improving rehabilitation programs.
- MeSH
- bezpečnost MeSH
- dopravní nehody prevence a kontrola psychologie MeSH
- dospělí MeSH
- empatie * MeSH
- funkční zobrazování neurálních procesů MeSH
- interpersonální vztahy MeSH
- kompetitivní chování MeSH
- kooperační chování MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mladý dospělý MeSH
- mozek diagnostické zobrazování fyziologie MeSH
- psychologické modely MeSH
- řízení motorových vozidel psychologie MeSH
- sociální chování MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Whiplash syndrom je způsoben extrémní flexí a následnou extenzí krční páteře. Nejčastější příčinou je autohavárie, nárazem do zadní části druhého automobilu, jehož posádka je vystavena riziku tohoto syndromu. Na základě klinického obrazu a vyšetření zobrazovacími metodami rozlišujeme tři typy postižení. Autoři demonstrují skupinu 28 nemocných s anamnézou, která svědčila pro whiplash syndrom. Závěrem autoři uvádějí návrh na algoritmus vyšetření pacientů s whiplash syndromem.
The whiplash syndrome is caused by extreme flexion and subsequent extension of the cervical spine. The most frequent cause are motor car crashes, collisions with the back part of another car the crew of which bears the risk of this syndrome. Based on the clinical picture and examination of imaging methods three types of affection are differentiated. The authors demonstrate a group of 28 patients with a history which suggested whiplash syndrome. In the conclusion the authors suggest an algorithm for examination of patients with whiplash syndrome.
Understanding the neural systems underpinning social cognition is a primary focus of contemporary social neuroscience. Using functional magnetic resonance imaging (fMRI), the present study asked if brain activity reflecting socio-cognitive processes differs between individuals according to their social behavior; namely, between a group of drivers with frequent traffic offenses and a group with none. Socio-cognitive processing was elicited by employing videos from a traffic awareness campaign, consisting of reckless and anti-social driving behavior ending in tragic consequences, and control videos with analogous driving themes but without such catastrophic endings. We investigated whether relative increases in brain function during the observation of these campaign stimuli compared with control videos differed between these two groups. To develop the results of our previous study we focused our analyses on superior temporal sulcus/gyrus (STS/STG). This revealed a bigger increase in brain activity within this region during the campaign stimuli in safe compared with dangerous drivers. Furthermore, by thematically coding drivers' verbal descriptions of the stimuli, we also demonstrate differences in STS reactivity according to drivers' scores on two indices of socio-cognitive processing: subjects' perceived consequences of actors' actions, and their affective evaluation of the clips. Our results demonstrate the influence of social behavior and socio-cognitive processing on STS reactivity to social stimuli, developing considerably our understanding of the role of this region in social cognition.
- MeSH
- dopravní nehody psychologie MeSH
- dospělí MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mapování mozku * MeSH
- mladý dospělý MeSH
- počítačové zpracování obrazu MeSH
- řízení motorových vozidel psychologie MeSH
- sociální chování * MeSH
- spánkový lalok patofyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- diskektomie metody MeSH
- dopravní nehody MeSH
- kraniocerebrální traumata * diagnóza chirurgie MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- paréza MeSH
- počítačová rentgenová tomografie metody MeSH
- poranění nervus abducens * patofyziologie MeSH
- poranění páteře diagnóza chirurgie MeSH
- senioři MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Devětatřicetiletý muž s anamnézou plastiky bikuspidální aortální chlopně byl přijat po autonehodě do Fakultní nemocnice Ostrava pro pravostrannou hemiparézu, zpomalené psychomotorické tempo a dezorientaci. Vstupní výpočetní tomografie (CT) prokázala subarachnoidální krvácení temporo-parietálně. Magnetická rezonance (MR) mozku odhalila difuzně lokalizovaná prokrvácená ischemická ložiska. Z ostatních vážných poranění měl nemocný rupturu sleziny s následným hemoperitoneem, která si vynutila urgentní splenektomii. V klinickém obraze nemocného dominovala neurologická symptomatologie, doplněná o petechie na končetinách a průkaz Staphylococcus aureus v likvoru i v hemokulturách. Z tohoto důvodu byla stanovena pracovní diagnóza meningoencefalitidy a nemocný byl léčen kombinací antibiotik. Vstupní transtorakální i transezofageální echokardiografické vyšetření bylo negativní. Teprve kontrolní jícnová echokardiografie, provedená s odstupem dvou týdnů od první pro recidivu febrilií, detekovala vegetace na aortální, mitrální chlopni a absces prominující na síňovou stranu předního mitrálního cípu. Vzhledem k nálezu vegetací byla přehodnocena diagnóza na infekční endokarditidu se septickými embolizacemi do mozku. Pro selhání konzervativní terapie infekční endokarditidy byla provedena náhrada aortální a mitrální chlopně, následovaná protrahovanou antibiotickou léčbou dle citlivosti. Dodatečným anamnestickým šetřením bylo zjištěno, že měsíc před manifestací onemocnění pacient utrpěl řezné poranění bérce, což mohla být vstupní brána infekce. Kazuistika prezentuje případ nemocného s obtížně a opožděně diagnostikovanou infekční endokarditidou, kde razantní antibiotická i chirurgická léčba vedla k plnému vyléčení nemocného.
A 39-year-old male with a history of bicuspid aortic valvuloplasty was admitted after a car accident for right-sided hemiparesis, cognitive slowing, and disorientation to the Teaching Hospital in Ostrava. Computed tomography (CT) at admission detected subarachnoidal bleeding in the temporoparietal region. Moreover, magnetic resonance imaging (MRI) detected small diffuse ischaemic lesions surrounded by microbleeds. Amongst other major injury, the patient suffered from splenic rupture, which led to urgent splenectomy. Major symptoms were of neurological origin, accompanied by forearm petechia and confirmed presence of Staphylococcus aureus in both blood samples and cerebrospinal fluid. Therefore preliminary diagnosis of meningoencephalitis was established and the patient was treated with combination of antibiotics. Transthoracic and transesophageal echocardiography at admission was negative. Not until the second echocardiography, performed two weeks after the first one, due to elevated body temperature, vegetations on both aortic and mitral valve and the abscess on atrial side of anterior mitral valve leaflet were observed. Therefore the meaning of petechia was rethought, and a new diagnosis of infective endocarditis (IE) with septic brain emboli was established. Due to the apparent failure of conservative treatment, the patient underwent aortic and mitral valve replacement, followed by prolonged cultivation-based antibiotic therapy. In addition, one month before the presentation patient suffered from cut injury of his shank, which may have been the entrance point of infection. This case report presents an elaborate and delayed IE diagnosis where both vigorous antibiotic and surgical treatment led to full recovery of the patient.
- Klíčová slova
- abdominalgie,
- MeSH
- antibakteriální látky terapeutické užití MeSH
- bolest etiologie MeSH
- chirurgická náhrada chlopně MeSH
- dopravní nehody MeSH
- dospělí MeSH
- echokardiografie transezofageální MeSH
- endokarditida * chirurgie diagnóza etiologie patologie MeSH
- hemoperitoneum diagnostické zobrazování MeSH
- horečka etiologie MeSH
- intrakraniální embolie MeSH
- ischemie mozku diagnostické zobrazování patologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- meningoencefalitida diagnóza MeSH
- mozek diagnostické zobrazování patologie MeSH
- neurologické manifestace * MeSH
- neúspěšná terapie MeSH
- paréza etiologie MeSH
- plíce diagnostické zobrazování patologie MeSH
- počítačová rentgenová tomografie MeSH
- poranění dolní končetiny komplikace MeSH
- purpura etiologie MeSH
- ruptura sleziny chirurgie diagnostické zobrazování MeSH
- splenektomie MeSH
- srdeční chlopně chirurgie patologie MeSH
- stafylokokové infekce etiologie krev mozkomíšní mok MeSH
- Staphylococcus aureus patogenita MeSH
- subarachnoidální krvácení diagnostické zobrazování patologie MeSH
- výsledek terapie MeSH
- zmatenost etiologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
... -- Band III of the Human Red Blood Cell Membrane Is a Transport Protein -- Bacteriorhodopsin Is a Proton ... ... Released by the Passage of Electrons Along the Respiratoiy Chain Is Stored as an Electrochemical Proton ... ... Gradient Across the Inner Membrane The Energy Stored in the Electrochemical Proton Gradient Across the ... ... Potential Across Each of the Three Respiratory Enzyme Complexes Provides the Energy Needed to Pump Protons ... ... The Mechanisms of Respiratory Proton Pumping Are Not Well Understood -- 500 -- 500 -- 501 -- 502 -- ...
xxxix, 1146 s. : il., tab. ; 28 cm
- MeSH
- biologie buňky MeSH
- molekulární biologie MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- biologie
- cytologie, klinická cytologie
High chromatographic resolution of wax esters (WEs) was achieved by non-aqueous reversed-phase liquid chromatography on a Nova-Pak C18 column by optimising the acetonitrile/ethyl acetate mobile phase gradient. The retention behaviour of WEs was studied in this chromatographic system. The WEs eluted according to their equivalent carbon number (ECN) values; within the group of WEs with the identical ECN, the most unsaturated species tended to elute first. The isobaric WEs with different positions of the ester moiety were separated from each other whenever the lengths of the chains were sufficiently different. The methyl-branched esters eluted at shorter retention times than the straight-chained analogues, and the resolution among methyl-branched WEs depended on the position of the branching. The analytes were detected by atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) using data-dependent scanning. WEs provided simple full-scan spectra with abundant protonated molecules and low-intensity fragments. Collision-induced dissociation (CID) promoted identification of the WE molecular species. The responses of WEs were found to be dependent on the number of double bonds and on the alkyl-chain length; the limits of the detection ranged from 20micromol/L to 200nmol/L. The HPLC/APCI-MS was applied for the analysis of the WEs isolated from honeycomb beeswax, jojoba oil and human hair. Good agreement between reported results and the literature data was achieved, with several novel polyunsaturated WEs also being found.
