异戊酸对非洲爪蟾卵母细胞膜上α1甘氨酸受体氯离子通道电流的影响

目的探讨异戊酸对甘氨酸受体氯离子通道的影响。方法采用微注射法在非洲爪蟾卵母细胞核中注射α1甘氨酸受体cDNA,在细胞膜上过度表达甘氨酸受体后,采用双电极全细胞膜片钳技术测定异戊酸对该受体氯离子通道电流变化的影响。结果5．0～20 mmol/L异戊酸可增强卵母细胞膜上甘氨酸受体氯离子通道内流电流（19%～187%,P＜0．01）,且呈浓度依赖性。结论异戊酸对α1甘氨酸受体氯离子通道电流有增强作用,其镇静催眠作用的机制可能与此有关。     

Colostomy tube: New device for a continent colostomy

PURPOSE: This study describes a new device (the colostomy tubus) for potentially establishing continence in patients with a diverted bowel. METHODS: The device was used in an animal experiment on dogs. The period of wearing the device was from one day to an uninterrupted insertion period of eight months. The device was used on an end sigmoid colostomy (4 dogs) and on a specifically shaped pouch stoma (2 dogs), in which the results proved most favorable. RESULTS: There were no complications caused by the device itself. The colostomy tubus seems to be a safe method of creating a continent colostomy and causes no tissue lesions. It proved reliable to wear. CONCLUSION: The device seems reasonable for human use, and a trial is currently under way.This study was performed at the University Gastroenterologic Clinic, Ljubljana, Slovenija, and the University Veterinary Hospital, Carnivores Division, at Trnovo, Ljubljana. Financially supported by the Research Community of Slovenia.Presented in part at the 8th World Congress of Enterostomal Therapists, Toronto, Canada, July 15 to 20, 1990.     

Different kinetic properties of two T-type Ca2+ currents of rat reticular thalamic neurones and their modulation by enflurane

Currents arising from T-type Ca²⁺ channels in nucleus reticularis thalami (nRT) play a critical role in generation of low-amplitude oscillatory bursting involving mutually interconnected cortical and thalamic neurones, and are implicated in the state of arousal and sleep, as well as seizures. Here we show in brain slices from young rats that two kinetically different T-type Ca²⁺ currents exist in nRT neurones, with a slowly inactivating current expressed only on proximal dendrites, and fast inactivating current predominantly expressed on soma. Nickel was about twofold more potent in blocking fast (IC₅₀ 64 μ m ) than slow current (IC₅₀ 107 μ m ). The halogenated volatile anaesthetic enflurane blocked both currents, but only the slowly inactivating current was affected in voltage-dependent fashion. Slow dendritic current was essential for generation of low-threshold Ca²⁺ spikes (LTS), and both enflurane and nickel also suppressed LTS and neuronal burst firing at concentrations that blocked isolated T currents. Differential kinetic properties of T currents expressed in cell soma and proximal dendrites of nRT neurones indicate that various subcellular compartments may exhibit different membrane properties in response to small membrane depolarizations. Furthermore, since blockade of two different T currents in nRT neurones by enflurane and other volatile anaesthetics occurs within concentrations that are relevant during clinical anaesthesia, our findings suggest that these actions could contribute to some important clinical effects of anaesthetics.     

Forensic botany: potential usefulness of microsatellite-based genotyping of Croatian olive (Olea europaea L.) in forensic casework

Aim

To assess genotyping with microsatellite-based markers of the olive (Olea europaea L.) for potential application of olive as legal case evidence, with regard to the degree of variability within the Croatian olive genomic pool and to the effectiveness of the chosen set of microsatellite-based markers in revealing olive divergence.

Methods

The total of 44 autochthonous Croatian olive specimens were subjected to genotyping with 16 previously described and developed microsatellite-based markers. According to previous morphological analyses, 44 specimens were classified into 30 cultivars with the exception of an additional, previously unassigned specimen.

Results

Genotyping of 44 specimens distinguished a total of 44 different genotype profiles by 16 microsatellite-based loci. Average expected heterozigosity amounted to 0.758, which points to significant diversity of Croatian olives.

Conclusion

Croatian olive genotyping showed strong varietal discrimination up to the single tree and considerable potential application of olive as evidence in investigation of crime, accident, and suicide circumstances.Forensic botany is the study of plants and plant material with the purpose of presenting the plant evidence in court. It includes a number of disciplines, such as plant anatomy and systematics palynology, plant ecology, limnology, plant chemistry, and plant molecular biology (1). In spite of its high potential in assessing the legal case evidence, only a few cases of plant forensic investigation applying DNA profiling, when a suspect was linked to the crime scene, were described (2,3). Plant DNA profiling serves to identify the origin of detected plant material connected to a crime, suicide, or accident, and hence, it may contribute to identifying the location(s) where the event took place (primary scene), recent location of the body, whether a victim had been transferred or moved (secondary scene), and whether a suspect was present at a crime or accident scene (4,5). DNA profiling is also employed in solving the issues of narcotics and drug enforcement, as well as of unauthorized commercialization of some plants.Microsatellite-based genotyping, due to its great reproducibility and high degree of certainty in assigning the origin of a biological material that serves as legal case evidence, represents one of the most reliable DNA profiling methods in forensic investigation (6).Microsatellites, short tandem repeats (STR) or simple sequence repeats (SSR) consist of a number of tandemly repeated short DNA sequences (1-6 base pairs long). They are distributed throughout the eukaryotic genome. In addition, microsatellites are multiallelic due to their high intraspecies variability and are easily amenable to polymerase chain reaction (PCR)-based analysis. Both characteristics make them the DNA markers of choice for human DNA profiling analyses. However, microsatellite-based markers found their way of wider application in different branches of animal and plant sciences.Olea europaea L. is a diploid, outcrossing species. Cultivated olives have been reproduced mainly by vegetative propagation and sporadically by cross-breeding, which resulted in the creation of a number of varieties due to accidental crosses between cultivated forms or between wild and cultivated forms, but also due to accumulation of mutations, along with local selection of outstanding individuals. Hence, most olive cultivars have a local origin. More than 2000 cultivars have been documented in the Mediterranean region by means of their morphology (7).At present, microsatellite-based DNA sequences are the most appropriate genetic markers used in olive cultivar characterization and classification. Many microsatellites have been isolated from olives and their respective primer pairs have been developed (8-14).Due to their mainly local origin, specific olive cultivars are indigenous to specific geographical areas. In addition, the same cultivars grown in different environmental conditions have different genotype profiles. Both olive characteristics ensure their relevance in the assessment of the location of origin of the olive sample in question.Olive trees are abundant in Croatia. In order to assess the application potential of Croatian olive DNA profiling in forensic investigations, we genotyped the total of 44 specimens that comprise 30 cultivars and their 13 varieties, as well as one unassigned olive specimen.     

Treatment of multiple sclerosis exacerbations

The understanding of the mechanisms that lead to MS exacerbations continues to produce novel treatments for patients with relapsing forms of MS. However, even with the most potent agents available, the exacerbations remain a distinct possibility and a source of concern for patients and clinicians. Therefore, the treatment of acute MS exacerbations remains an indispensable element of MS care. Reviewed here are the available treatment options, their implementation, side effects, and evidence supporting their efficacy in promoting recovery from MS relapses.     

Maturation to elite status: a six-year physiological case study of a world champion rowing crew

This case study reports the results of a 6-year (2005–2010) follow-up study of a world-class rowing crew, the current world champions. The rowers were 15–16 years old and prospective competitors at the junior level when the study began in 2005, and we monitored their physical, physiological, and rowing ergometer performance data annually. Our findings indicated that over the 6-year period gains in stature, averaged across rowers, amounted to only +2 cm (+1%). In contrast, body mass increased by +9 kg (+10%) and fat-free mass by +11 kg (+15%). A significant linear trend (R ² = 0.998, P < 0.001) and a +26% increase in maximal oxygen uptake (in L min⁻¹) was evident from 2005 to 2009, resulting in a leveling-off and a crew average of ~6.6 L min⁻¹ (~70 mL kg⁻¹ min⁻¹) during the last 2 years of assessment. Power output at anaerobic threshold increased by +23%, subsequently amounting to a crew average of 359 W in 2010. Oxygen uptake at anaerobic threshold, expressed as a percentage of maximal oxygen uptake, changed little and ranged between 82 and 85%. A curvilinear regression provided the best fit to describe the 6-year improvement (+7%) in 2000 m (R ² = 0.984, P < 0.001) and 6000 m (R ² = 0.989, P < 0.001) rowing ergometer performance times. Performance-related physical and physiological parameters seem to level-off at about 20 years of age, which may partly explain the corresponding stabilization in ergometer performance times over the last years of assessment.     

Photoacoustic tomography of ex vivo mouse hearts with myocardial infarction

In the present study, we evaluated the applicability of ex vivo photoacoustic imaging (PAI) on small animal organs. We used photoacoustic tomography (PAT) to visualize infarcted areas within murine hearts and compared these data to other imaging techniques [magnetic resonance imaging (MRI), micro-computed tomography] and histological slices. In order to induce ischemia, an in vivo ligation of the left anterior descending artery was performed on nine wild-type mice. After varying survival periods, the hearts were excised and fixed in formaldehyde. Samples were illuminated with nanosecond laser pulses delivered by a Nd:YAG pumped optical parametric oscillator. Ultrasound detection was achieved using a Mach-Zehnder interferometer (MZI) working as an integrating line detector. The voxel data were computed using a Fourier-domain based reconstruction algorithm, followed by inverse Radon transforms. The results clearly showed the capability of PAI to visualize myocardial infarction and to produce three-dimensional images with a spatial resolution of approximately 120 μm. Regions of affected muscle tissue in PAI corresponded well with the results of MRI and histology. Photoacoustic tomography utilizing a MZI for ultrasound detection allows for imaging of small tissue samples. Due to its high spatial resolution, good soft tissue contrast and comparatively low cost, PAT offers great potentials for imaging.