The hypotransferrinaemic mouse: Ultrastructural and laser microprobe analysis observations

Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals.     

Universal Mindfulness Training in Schools for Adolescents: a Scoping Review and Conceptual Model of Moderators,Mediators, and Implementation Factors

Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such...     

Characterization of mechanical withdrawal responses and effects of mu-, delta- and kappa-opioid agonists in normal and mu-opioid receptor knockout mice

Clinical and experimental observations suggest that opiates can exert different influences on the perception of stimuli from distinct sensory modalities. Thermally-induced nociception is classically responsive to opiate agonists. mu-Opioid receptor-deficient transgenic mice are more sensitive to thermal nociceptive stimuli and morphine fails to attenuate the nociceptive responses to thermal stimuli in these animals. To enhance our understanding of opiate influences on mechanical sensitivity, we have examined withdrawal responses to a sequence of ascending forces of mechanical stimuli in mice with normal (wild type), half-normal (heterozygous) and absent (homozygous) mu-opioid receptor levels. We report data from mice examined without drug pretreatment or following pretreatment with morphine, the selective kappa-opioid agonist, U50488H, and the selective delta-opioid agonist, DPDPE. Saline-pretreated mice of each genotype displayed similar, monotonically increasing frequency of withdrawal responses to the graded stimuli. Subcutaneously administered morphine produced a dose-dependent reduction in withdrawal responses in wild type and heterozygous mice, but had no significant effect in homozygous mice. Intraventricular administration of DPDPE also reduced the frequency of paw withdrawal (FPW) in wild type mice, but not in homozygous mice. In contrast, systemic U50488H produced a dose-dependent attenuation of paw withdrawal in both wild type and homozygous mice. These findings suggest that (1) interactions of endogenous peptides with mu-opioid receptors may not play a significant role in the response to mechanical stimuli in drug-free animals, and (2) deficiency of mu-opioid receptors has no functional consequence on the response to the prototypical kappa-opioid receptor agonist, but decreases responses to the prototypical mu- and delta-opioid receptor agonists.     

Trans-axillary first rib excision for thoracic outlet syndrome

AIM: Thoracic outlet syndrome (TOS) is a clinical diagnosis treatable by excision of the first rib. This study was undertaken to assess the alleviation of symptoms following trans-axillary rib excision in patients with a diagnosis of TOS suggested by a positive Elevated Arm Stress Test and, by inference, to estimate the prevalence of the syndrome. METHOD: A retrospective review of trans-axillary first rib excision was performed. No referrals were accepted from outwith the catchment area of our hospital. Post-operative symptomatic improvement was accepted as a confirmation of correct pre-operative diagnosis. RESULTS: Over six years, 52 rib resections were performed in 46 patients, mean age (+/- S.D.) 38.8 (+/- 10.6) years. The indications for surgery were principally neurological symptoms (n = 42 excisions), arterial compromise (n = 5) and venous compromise (n = 5). Symptoms had been present for a mean of 15.8 months prior to surgery. The median follow-up after surgery was 33 months. 42 patients (48 resections) showed immediate improvement in symptoms following surgery, although symptoms recurred in three patients (4 resections) between 6 and 8 months post-operatively. In the final two years of this study, 20 resections resulting in symptomatic improvement were performed, suggesting a prevalence for TOS of at least 10 per 100,000 per year. CONCLUSIONS: Thoracic outlet decompression was performed more frequently in this series than many previous reports, suggesting that TOS may be under-diagnosed.     

Jet stream related iatrogenic retinal breaks during vitreo-retinal surgery

Purpose:To evaluate the causes of jet stream injury (JSI)-related iatrogenic retinal breaks (IRBs) during vitreoretinal surgery (VRS).Methods:The precise surgical environment, which includes the indication and type of surgical procedure, retina status, details of instrumentation and fluidic parameters, and characteristics of the jet responsible for the IRB, was noted from case records. The nature of IRB and its healing and impact on anatomical and visual outcomes were analyzed.Results:Five eyes of five patients with complete documentation of both the JSI and the IRB were included. Two cases were operated for macular hole, and one each for vitreous hemorrhage, retinal detachment, and endophthalmitis. One case had infusion-fluid-related JSI, while four developed it because of injection of surgical adjuncts (drugs, PFCL, and dye). JSI developed in two cases when the vitreous cavity was filled with fluid, while it was air-filled in three cases. In four cases, the fluid migrated into subretinal space, necessitating further maneuvers following which the breaks healed, but were directly responsible for vision loss in two cases.Conclusion:JSI related IRBs are rare but may be directly responsible for vision loss if they impact the macula. The balance between jet stream velocity, its distance from the retinal surface, the intervening media (vitreous cavity), and retinal health play an important role. It can occur because of both infusion as well as injection jets. Precautions must be taken in cases vulnerable to complications with suggested modifications in the surgical technique.     

视神经周围炎的研究进展

视神经周围炎(OPN)是指涉及视神经鞘膜的一系列病理性炎症.OPN的经典三联征包括单侧视神经病变伴随疼痛和/或视盘水肿,此病症与其它视神经病变相似,导致诊断延迟和治疗欠佳.2016年1月,我们对发表于Medline和Ovid数据库的关键词为“视神经周围炎”的各种语言的文献进行了检索,共查找到60篇文献,发表于1956-2015年.两位作者(Tai ELM和Tevaraj JMP)分别对论文摘要进行了独立筛选,并筛选出相关文章.本次综述,我们强调OPN的特点,特别是OPN和视神经炎之间的临床差异.虽然大多数OPN的病例是特发性的,但仍需进行调查以排除特异性感染和继发性OPN的炎症原因.MRI是非常重要的检查方法,由于OPN视神经周围炎症的影像学诊断.糖皮质激素治疗可使症状与体征迅速好转,长期口服糖皮质激素并慢速递减可以降低复发的风险.