Long‐term accumulation of microglia with proneurogenic phenotype concomitant with persistent neurogenesis in adult subventricular zone after stroke

Neural stem cells (NSCs) in the adult rat subventricular zone (SVZ) generate new striatal neurons during several months after ischemic stroke. Whether the microglial response associated with ischemic injury extends into SVZ and influences neuroblast production is unknown. Here, we demonstrate increased numbers of activated microglia in ipsilateral SVZ concomitant with neuroblast migration into the striatum at 2, 6, and 16 weeks, with maximum at 6 weeks, following 2 h middle cerebral artery occlusion in rats. In the peri‐infarct striatum, numbers of activated microglia peaked already at 2 weeks and declined thereafter. Microglia in SVZ were resident or originated from bone marrow, with maximum proliferation during the first 2 weeks postinsult. In SVZ, microglia exhibited ramified or intermediate morphology, signifying a downregulated inflammatory profile, whereas amoeboid or round phagocytic microglia were frequent in the peri‐infarct striatum. Numbers of microglia expressing markers of antigen‐presenting cells (MHC‐II, CD86) increased in SVZ but very few lymphocytes were detected. Using quantitative PCR, strong short‐ and long‐term increase (at 1 and 6 weeks postinfarct) of insulin‐like growth factor‐1 (IGF‐1) gene expression was detected in SVZ tissue. Elevated numbers of IGF‐1‐expressing microglia were found in SVZ at 2, 6, and 16 weeks after stroke. At 16 weeks, 5% of microglia but no other cells in SVZ expressed the IGF‐1 protein, which mitigates apoptosis and promotes proliferation and differentiation of NSCs. The long‐term accumulation of microglia with proneurogenic phenotype in the SVZ implies a supportive role of these cells for the continuous neurogenesis after stroke. © 2008 Wiley‐Liss, Inc.     

Insular resting state functional connectivity is associated with gut microbiota diversity

The gut microbiota has recently gained attention as a possible modulator of brain activity. A number of reports suggest that the microbiota may be associated with neuropsychiatric conditions such as major depressive disorder, autism and anxiety. The gut microbiota is thought to influence the brain via vagus nerve signalling, among other possible mechanisms. The insula processes and integrates these vagal signals. To determine if microbiota diversity and structure modulate brain activity, we collected faecal samples and examined insular function using resting state functional connectivity (RSFC). Thirty healthy participants (non‐smokers, tobacco smokers and electronic cigarette users, n = 10 each) were studied. We found that the RSFC between the insula and several regions (frontal pole left, lateral occipital cortex right, lingual gyrus right and cerebellum 4, 5 and vermis 9) were associated with bacterial microbiota diversity and structure. In addition, two specific bacteria genera, Prevotella and Bacteroides, were specifically different in tobacco smokers and also associated with insular connectivity. In conclusion, we show that insular connectivity is associated with microbiome diversity, structure and at least two specific bateria genera. Furthemore, this association is potentially modulated by tobacco smoking, although the sample sizes for the different smoking groups were small and this result needs validation in a larger cohort. While replication is necessary, the microbiota is a readily accessible therapeutic target for modulating insular connectivity, which has previously been shown to be abnormal in anxiety and tobacco use disorders.     

Molecular systematics of filarial parasites, with an emphasis on groups of medical and veterinary importance, and its relevance for epidemiology

Filarial parasites are members of the Phylum Nemata that comprise several species of medical and veterinary importance. Among the human diseases caused by members of this group of nematodes are river blindness and lymphatic filariasis, which afflict millions of people in the tropics. These diseases not only have an impact on the health of the people affected but also bear a great socioeconomic burden. Despite their relevance, the systematics of the filarial parasites is not well understood yet, and additional molecular phylogenetic studies are required to comprehend the evolution of these parasites. Identifying the patterns of evolution of these parasites will be of relevance in preventing emerging zoonoses. The present review examines the information about the molecular systematics of filarial parasites available in the literature and evaluates the relevance of the different directions of future research. Furthermore, it is also intended to highlight the relevance of molecular systematic studies in the molecular epidemiology research area.     

Renal allograft laceration treated by superselective embolization.

PURPOSE: To report an illustrative case demonstrating the efficacy of endovascular treatment for traumatic blunt renal allograft injury. CASE REPORT: A 19-year-old man sustained an injury to his renal allograft after a traffic accident secondary to lap belt compression. Angiography revealed contrast extravasation from 2 disrupted upper pole renal artery branches, which were successfully embolized with microcoils. The creatinine level was transiently elevated to 4.1 mg/dL, but it improved to 2.9 mg/dL at discharge 13 days after admission. After 1 year, the serum creatinine level was 1.9 mg/dL. CONCLUSION: As in the native kidney, superselective embolization can also be used safely in the management of blunt injury to a renal allograft, avoiding surgery and preserving graft function.