Recall of emotional and neutral words and paragraphs in traumatic brain injury

Background: Traumatic brain injury (TBI) results in verbal recall deficits and impaired processing of emotion encoded in facial appearance, prosody and the linguistic content of messages. Emotion facilitates memory (emotional memory advantage) for non-brain injured (NBI) individuals but the impact of emotion on verbal recall for linguistically encoded stimuli in TBI has not been explored.

Aims: The purpose of this study was to determine the effects of stimulus emotional content on verbal recall of words and paragraphs in TBI compared to NBI individuals.

Methods and procedures: Six 10-item lists, each with five emotional and five neutral words, and six paragraphs (three emotional, three neutral) were counterbalanced and presented in random order to 20 individuals with TBI and 44 NBI. The number of words from lists and the number of content units from paragraphs were compared for the two groups.

Outcomes and results: The NBI participants recalled more words from the lists and content units from the paragraphs than the individuals with TBI. Both groups recalled significantly more emotional than neutral words. NBI but not TBI participants had significantly greater recall for information in paragraphs with emotional content.

Conclusions: Participants with TBI showed impaired recall of words and paragraph content. Emotion facilitated word and paragraph content recall for neurotypical individuals but emotional memory advantage was limited to words for the TBI participants.     

High-resolution optical coherence tomography as a non-destructive monitoring tool for the engineering of skin equivalents

BACKGROUND: Three dimensional skin equivalents are widely used in dermatopharmacological and toxicological studies and as autologous transplants in wound healing. In pharmacology, there is tremendous need for monitoring the response of engineered skin equivalents to external treatment. Transplantation of skin equivalents for wound healing requires careful verification of their quality prior to transplantation. Optical coherence tomography (OCT) is a non-contact, non-destructive imaging technique for living tissues offering the potential to fulfill these needs. This work presents an analysis of OCT for high-resolution monitoring of skin equivalents at different stages during the culture process. METHODS: We developed a high-resolution OCT imaging setup based on a commercially available OCT system. A broadband femtosecond laser light source replaces the original superluminescence diode. Tomograms of living skin equivalents were recorded with an axial resolution of 3 mum and correlated with histology and immunofluorescence images. Comparison with standard low-resolution OCT is presented to emphasize the advantages of high-resolution OCT for this application. RESULTS: OCT is particularly able to distinguish between different layers of skin equivalents including stratum corneum, epidermal and dermal layer as well as the basement membrane zone. The high-resolution OCT scans correlate closely with two key benchmarks, histology and immunofluorescence imaging. CONCLUSIONS: This study clearly demonstrates the benefits of high-resolution OCT for identifying living tissue structure and morphology. Compared with the current gold standard histology, OCT offers non-destructive tissue imaging, enabling high-resolution evaluation of living tissue morphology and structure as it evolves.     

Neuronal regeneration after application of radiofrequency energy to collagenous tissue is affected by limb immobilization: an in vivo animal study.

Despite widespread use of radiofrequency (RF)-shrinkage, there have been no studies on the influence of RF-energy on neural elements of collagenous tissue. The purpose of this study was to examine the effect of RF-shrinkage on neural structures of capsuloligamentous tissue and the recovery of neural elements under different postoperative treatment protocols. One patellar tendon of 46 New-Zealand-White rabbits was shrunk. Six rabbits were sacrificed immediately postoperative. Twenty rabbits were not immobilized, 10 were immobilized for 3 and 10 were immobilized for 6 weeks. A monoclonal antibody, specific against a neurofilament protein, was used to detect nerves and neural structures. Staining pattern of nerve fibres was significantly altered immediately postoperative. After 3 weeks the number of nerve fibres and bundles decreased significantly in immobilized and non-immobilized limbs. The loss of nerve fibres was significantly less in immobilized limbs. At 6 weeks the number of neural elements in immobilized limbs increased to the level of untreated control tissue. In non-immobilized limbs we found no recovery of neural elements 9 weeks postoperatively. At this time the number of nerve fibres and bundles was still significantly less compared to the untreated control limbs. RF-shrinkage causes significant alteration of neural elements. Under immobilization nerve fibres and bundles reach the level of normal untreated tissue. Careful rehabilitation is important after RF-shrinkage. Not only for biomechanical reasons, but also to allow the neural elements to recover, thermally modified tissue should be protected from normal physiologic loads.     

Ocular hemodynamics following suction cup oculopression

In the study reported here the authors investigated the influence on ocular perfusion pressures of suction-cup oculopression, a procedure which permits oculopression without orbital compression. Patients over 50 years of age were examined before cataract extraction. Ulrich's method of ocular oscillodynamography was used to determine ocular perfusion pressures. A Mikuni and Yoneyama suction-cup dynamometer was applied for suction-cup oculopression. Ocular hypotonia following suction-cup oculopression was adequate and comparable to that achieved by other oculopression methods. After oculopression a significant increase in ocular perfusion pressures (retinal, ciliary, and diastolic) was found. However, ocular blood pressure remains constant after oculopression. Moreover, the increase in ocular perfusion pressure could not be explained by oculocardiac reflexes, because there was no change in systemic arterial blood pressure. It must be assumed, therefore, that the increase in ocular perfusion pressures is caused by a lowering of resistance, i.e., a drop in intraocular pressure.     

Über die Oxydation von Adrenalin in Bernsteinsäure unter besonderer Berücksichtigung der Luminolreaktion

Research in Experimental Medicine - Es konnte gezeigt werden, daß frisch zubereitete Bernsteinsäure-und Fumarsäurelösungen bei einem sauren pH keine positive Luminolreaktion...     

Antagonism of airway reactivity induced by ovalbumin antigen in guinea pigs by 5-amino-4-imidazolecarboxamide riboside

The effect of 5-amino-4-imidazolecarboxamide riboside (AICA riboside), a modulator of purine metabolism, was studied on antigen-induced bronchospasm in ovalbumin (OA)-sensitized guinea pigs. In separate experiments, sodium cromoglycate (SCG) and terbutaline were used to compare their effectiveness with that of AICA riboside (wt/vol). AICA riboside and SCG were administered as an aerosol daily for a minimum of 2 weeks before OA aerosol challenge. Terbutaline, as an aerosol, was administered once 5 minutes before OA challenge. Airway reactivity was determined through the use of a whole-body plethysmography by monitoring specific airway resistance (SRaw). OA aerosol challenge of 0.05%, 0.1%, and 0.25% (wt/vol), administered for a period of 1 minute, increased SRaw. Each of the three agents attenuated the effect of OA on SRaw, although terbutaline demonstrated more consistency and potency as compared to either AICA riboside or SCG. However, at moderate degrees of OA challenge, AICA riboside appeared to be as effective as either agent. Although the mechanism of action of AICA riboside remains uncertain, it may have therapeutic benefit in the treatment of asthma or allergic diseases.     

Detection and localization of single-base sequence differences in foot-and-mouth disease virus genomes by the RNase mismatch cleavage method.

The RNase mismatch cleavage method was examined for its efficiency of indicating single-base sequence differences in the capsid protein-coding regions of different foot-and-mouth disease virus subtype O1 strains. The method was found suitable for indicating such differences. RNase A as well as RNase T1 contributed to substrate conversion. Examples for the cleavage of eleven different single-base mismatches in RNA double-strands are now known. All virus genomes found to differ from each other exhibited three or more non-neighboured single-base sequence differences. Other genomes found to be indistinguishable by this method were those of a recent field isolate adapted to cell culture, and those of a vaccine production strain; its progeny was transmitted to pig and cow and then analyzed. The results suggest that host change does not necessarily select for antigenic variant virus, and that virus submitted to some kind of selection pressure is changed at more than one position.     

Retrograde flush following topical cooling is superior to preserve the non-heart-beating donor lung

Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex^® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm⁻⁵) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH₂O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH₂O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.     

Ocular hemodynamics following local administration of clonidine

The influence of topically applied clonidine 0.125% on ocular hemodynamics was investigated in ten patients with open-angle glaucoma and ten healthy volunteers, using a new, differentiated method. Ocular perfusion pressures were determined by Ulrich's method of oculo-oscillodynamography. Following monocular application of clonidine 0.125% eye drops a clear decrease in systemic blood pressure and a somewhat less pronounced reduction of ocular perfusion pressure was observed in both groups of patients. The reduction in ocular perfusion pressures was higher in the eye after drop application than in the untreated control eye. It must therefore be assumed that clonidine 0.125% eye drops have a local perfusion pressure-reducing effect in addition to their systemic effect.