[A Case of Unilateral Multiple Cerebral Edema 4 Weeks after Coil Embolization].

Coil embolization for cerebral aneurysms can lead to various complications, such as aneurysm rupture and cerebral embolism. In recent years, foreign substance embolisms-caused by peeling off of coating materials from therapeutic devices-have been described. We report here a case of unilateral multiple cerebral edema four weeks after coil embolization. A 44-year-old woman presented with a subarachnoid hemorrhage from a right internal carotid-posterior communicating artery aneurysm, for which coil embolization was performed. Four weeks after the embolization, she developed numbness in the left side of her mouth and in her left upper extremity. Magnetic resonance images showed multiple edematous lesions in the right cerebral hemisphere. Subsequent treatment with steroids improved her symptoms and edematous cerebral lesions. Although definitive diagnosis by biopsy was not performed, her clinical course and imaging findings resembled a foreign substance embolism by hydrophilic coating. It is important to note that delayed cerebral edema due to foreign substance embolisms might occur after endovascular treatments.

Higher abundance of Campylobacter in the oral microbiome of Japanese patients with moyamoya disease.

Genetic factors alone cannot explain the pathophysiology of moyamoya disease (MMD), and environmental factors such as an immune response are thought to be involved. Oral and gut microbiomes have attracted attention as environmental factors in the pathophysiology of some vascular and autoimmune diseases. However, the relationship between MMD and these microbiomes is yet to be thoroughly investigated. This prospective case-control study aimed to compare the microbiomes of Japanese patients with MMD with those of healthy individuals to identify the specific bacteria involved in MMD. Saliva and fecal samples were collected from 16 patients with MMD who had not undergone revascularization surgery. Fifteen healthy individuals were matched for age, sex, and body mass index. The microbiomes were determined using 16S rRNA sequencing and analyzed using QIIME2. Differentially abundant microbes were identified using LEfSE and ANCOM-BC. In the oral microbiome, the two analytical methods showed that Campylobacter was more abundant in patients with MMD than in healthy individuals. Differences in the gut microbiome were smaller than those in the oral microbiome. In conclusion, the oral microbiome profiles of patients with MMD significantly differ from those of healthy individuals. Campylobacter spp. could be a substantial environmental factor in the pathophysiology of MMD.

Ultrafiltration significantly increased the scaling potential of municipal secondary effluent on reverse osmosis membranes.

Ultrafiltration (UF) was often used as pretreatment in front of reverse osmosis (RO) unit because of its high rejection efficiency of microbes and particles. However, in some cases UF pretreatment might show adverse effects on the RO membrane flux. In this study, the effects of UF pretreatment on secondary effluent water quality and its RO membrane fouling characteristics were explored. There was almost no change of water quality after UF with different molecular weight cut-off (MWCO) membranes (100, 30 and 10 kDa), including total dissolved solid (TDS), alkalinity, conductivity, ion concentrations, etc., while pH increased a little and dissolved organic carbon (DOC) declined by about 1 mg/L. On the contrary, the RO membrane flux of UF permeates presented clear decline in comparison to the secondary effluent. The membrane fouling velocity and steady-state flux of secondary effluent was 0.052 and 0.656, while fouling velocity increased (0.077, 0.071, 0.067) and steady-state flux decreased significantly (0.397, 0.416, 0.448) after 100, 30, 10 kDa UF membrane pretreatment. Scanning electron microscope (SEM) images showed many crystals on the fouled membrane surfaces, which turned out to be CaCO3 by Energy dispersive spectrometer (EDS) analysis and precipitation calculation. After the addition of UF retentates to UF permeates, scaling was prevented and crystals on the RO membrane almost disappeared, which implied the anti-scaling effect of the UF retentates with low concentration. According to anti-scaling performance experiments, the anti-scaling performance of 100 k, 30 k, 10 k retentates was 2.7%, 4.0% and 7.3%, respectively. Excitation emission matrix (EEM) and fourier transform infra-red (FTIR) results showed that these retentates retained by different MWCO membranes were similar and composed of protein-like substances and soluble microbial products. The effect of key minority components in RO system deserved further exploration.

Comparison of disinfection-residual-bacteria (DRB) after seven different kinds of disinfection: Biofilm formation, membrane fouling and mechanisms.

Membrane fouling is the Achilles' heel of the reverse osmosis (RO) system for high-quality reclaimed water production. Previous studies have found that after the significant selection effect of traditional disinfection, the remaining disinfection-residual bacteria (DRB) may possess more severe biofouling potentials. To provide more constructive advice for the prevention of biofouling, we compared the RO membrane fouling characteristics of DRB after using five commonly used disinfection methods (NaClO, NH2Cl, ClO2, UV, and O3) and two novel disinfection methods (K2FeO4 and the flow-through electrode system (FES)). Compared with the control group (undisinfected, 21.1 % flux drop), the UV-DRB biofilm aggravated biofouling of the RO membrane (23.4 % flux drop), while the FES, K2FeO4, and NH2Cl treatments showed less severe biofouling, with final flux drops of 6.9 %, 8.1 %, and 8.1 %, respectively. Adenosine triphosphate (ATP) was found to be a capable indicator for predicting the biofouling potential of DRB. Systematic analysis showed that the thickness and density of the DRB biofilms were most closely related to the different fouling degree of RO membranes. Moreover, the relative abundance of bacteria with higher extracellular polymeric substance (EPS) secretion levels, such as Pseudomonas and Sphingomonas, was found closely related with the biofouling degree of RO membranes.

Different bacterial species and their extracellular polymeric substances (EPSs) significantly affected reverse osmosis (RO) membrane fouling potentials in wastewater reclamation.

Biofouling represents the "Achilles' heel" for reverse osmosis (RO) processes due to the growth of bacteria and their production of extracellular polymeric substances (EPSs). Although the microbial community structure on the RO membrane has been analysed previously, the bacterial species with a high potential of causing RO membrane fouling have not yet been identified clearly. The key components in EPSs causing RO membrane fouling have not been revealed either. In this study, seven different bacterial species were isolated from fouled RO membranes, and their EPSs were analysed in terms of the content of polysaccharides and proteins, fluorescence characteristics and molecular weight (MW) distributions. The membrane fouling potentials of these bacterial species and EPSs were evaluated based on normalized flux decline. Generally, under the same growth conditions, bacterial species with higher EPS concentrations, rather than higher cell numbers, resulted in more severe flux decline. The flux decline showed an apparent positive correlation with the EPS concentration, indicating that the concentration of EPS rather than the bacterial number mainly contributed to biofouling. Furthermore, it was found that the MW distribution was the key factor affecting the RO membrane fouling potential of EPSs from different bacterial species. With the increase in the percentage of the high-MW fraction (>10 kDa) in the EPSs from 12.6% to 74.4%, the normalized flux decline increased from 0.4 to 0.59. The components in EPSs with a MW over 10 kDa were also separated by the ultrafiltration membrane and were proven to have a higher membrane fouling potential.