Membrane Removal Research Articles

Hybrid adsorptive nanofiltration hollow fiber membranes with charge-patterned UiO-66 incorporated thin-film nanocomposite selective layer for enhanced boron removal

Herein, hybrid adsorptive nanofiltration (NF) hollow fiber (HF) membranes with the charge-patterned structure were fabricated and characterized for enhanced boron removal application. Mg–Al layer double hydroxide (LDH) and bentonite nanoparticles (NPs) were used as adsorbents in the support layer, while pristine and novel amine modified UiO-66 metal-organic frameworks (MOFs) were used to synthesize thin-film nanocomposite polyamide (PA) selective layer. UiO-66 was modified using triethylamine (TEA) and polyethylene imine (PEI) and the modification was approved through FTIR, DLS, and FESEM analyses. Prior to the performance evaluation of the fabricated membranes, the feasibility of boron removal by PA, and pristine and modified UiO-66 was investigated using molecular dynamics (MD) simulation and the diffusion coefficients were estimated. The structure of the fabricated thin film composite (TFC) and thin film nanocomposite (TFN) membranes were characterized by AFM, zeta potential and FESEM analyses showing agglomeration of the MOFs at 0.1 wt%. Membrane performance in boron removal was evaluated through brackish water condition at 4 bar in neutral and alkaline pH. The results showed that the contribution of the adsorptive support is 8 and 4% for the supports containing LDH and bentonite, respectively. Boron removal of the UiO-66 TFN membrane was achieved up to 58%, while the charge-patterned UiO-66/PEI TFN membrane was able to remove boron up to 87 and 91% at neutral and alkaline pH conditions.

Long-term Outcomes of Vitrectomy with Internal Limiting Membrane Removal to Treat Macular Hole Retinal Detachment

Purpose: To evaluate the long-term clinical outcomes of vitrectomy with internal limiting membrane (ILM) removal for patients with macular hole retinal detachment (MHRD).Methods: We retrospectively reviewed the medical records of patients with MHRD who underwent vitrectomy with ILM removal. The incidence of retinal re-attachment and MH closure at 1 month were calculated. Factors associated with RD recurrence were investigated. Visual acuity before surgery was compared to that at the final visit.Results: Forty-two eyes were included; the mean follow-up period was 38.5 ± 19.1 months. Twenty-three eyes received gas injections and 19 silicone oil injections. Retinal re-attachment occurred in 41 (97.6%). Type 1 closure was noted in 21 eyes (51.2%) and type 2 in 20 (48.8%). Recurrent RD was noted in five eyes (14.6%) within 3 months of initial surgery. Type 2 closure was a risk factor for recurrence (p = 0.021). The logarithm of the minimum angle of resolution best-corrected visual acuity improved significantly from 1.79 ± 0.79 before surgery to 1.30 ± 0.75 after surgery (p < 0.001).Conclusions: Retinal re-attachment was noted in most patients and the MH closed in approximately half of all patients after vitrectomy with ILM removal to treat MHRD. RD did not recur later than 3 months after initial surgery. Further efforts to increase the rate of type 1 closure are required.

Functional results and complications in the long-term follow-up after 25-gauge vitrectomy of epiretinal membrane

Idiopathic epiretinal membranes can lead, among other things, to visual impairment and metamorphopsia. The treatment of choice is apars plana vitrectomy with removal of the membrane. The improvement of visual acuity and postoperative complications have already been described in several studies. The aim of this retrospective study is to evaluate the long-term outcome of at least 3years. In the period from 2011 to 2016, atotal of 667eyes underwent 25-gauge pars plana vitrectomy, membranectomy and peeling of the ILM (Internal limiting membrane) because of epiretinal membrane by the same surgeon. This study included 51eyes from 51patients who had returned to our clinic after at least 3years. For the follow-up, data were collected after 3months and then annually, if available. The mean follow-up time was 57months (37-104months). In the postoperative follow-up visual acuity, intraocular pressure and complications were recorded. Of the 51eyes included 34had a25-gauge pars plana vitrectomy with phacoemulsification and artificial lens implantation, 8eyes without phako and 9eyes were already pseudophakic. The most common complication in the follow-up period was apersistent macular edema with 5.9% (3eyes) and arecurrence of epiretinal membrane in 5.9% of cases. The best corrected logMar visual acuity was 0.4 (0.1-1.3; n = 51) preoperatively, at the last examination 0.23 (0-1.0; n = 51, p < 0.001). Three months postoperatively, the logMar visual acuity was 0.29 (n = 41), after 1year 0.25 (n = 35), 2years 0.23 (n = 29), after 3years 0.26 (n = 29), after 4years 0.27 (n = 27), after 5years 0.24 (n = 17) and after 6years 0.24 (n = 13). The 25-gauge pars plana vitrectomy is alow complication procedure for the removal of epiretinal membranes. The clearest increase in visual acuity can be seen within the first 3months postoperatively, but then stabilizes. In the long-term follow up achange in visual acuity can also be found after more than 3years.

Combined Model of OCT Angiography and Structural OCT Parameters to Predict Paracentral Visual Field Loss in Primary Open-Angle Glaucoma

To assess a model combining OCT angiography (OCTA) and OCT parameters to predict the severity of paracentral visual field (VF) loss in primary open-angle glaucoma (POAG). Cross-sectional study. Forty-four patients with POAG and 42 control subjects underwent OCTA and OCT imaging with a swept-source OCT device. The circumpapillary microvasculature was quantified for vessel density (cpVD) and flow (cpFlow) after delineation of Bruch's membrane opening and removal of large vessels. Retinal nerve fiber layer thickness (RNFLT) and Bruch's membrane opening-minimum rim width (BMO-MRW) were measured from structural OCT. Paracentral total deviation (PaTD) was defined as the average of the total deviation values within the central 10 degrees on Humphrey VF testing (24-2) for upper and lower hemifields. The OCT and OCTA parameters were measured in the affected hemisphere corresponding to the hemifield with lower PaTD for POAG patients. Models were created to predict affected PaTD based on RNFLT alone; RNFLT and BMO-MRW; OCTA alone; or RNFLT, BMO-MRW and OCTA parameters. The models were compared using coefficient of determination (r2) and Bayesian information criterion (BIC) score. Bayesian information criterion decrease of ≥6 indicates strong evidence for model improvement. Performance of models containing OCT and OCTA parameters in predicting PaTD. Patients with POAG and controls were similar in age and sex (65.9 ± 9.5 years and 38.4% male overall, P ≥ 0.56 for both). Average RNFLT, minimum RNFLT, average BMO-MRW, minimum BMO-MRW, cpVD, and cpFlow were all significantly lower (all P < 0.001) in the affected hemisphere in patients with POAG than in controls. In patients with POAG, the average mean deviation was -4.33 ± 3.25 dB; the PaTD of the affected hemifield averaged -4.55 ± 5.26 dB and correlated significantly with both OCTA and structural OCT parameters (r ≥ 0.43, P ≤ 0.004 for all). The model containing RNFLT, BMO-MRW, and OCTA parameters was superior in predicting affected PaTD (r2= 0.47, BIC= 290.7), with higher r2 and lower BIC compared with all 3 other models. A combined model of OCTA and structural OCT parameters can predict the severity of paracentral VF loss of the affected hemifield, supporting clinical utility of OCTA in patients with POAG with paracentral VF loss. Proprietary or commercial disclosure may be found after the references.

Endoscope-Assisted Evacuation of Nonacute Subdural Hematoma: A Technical Case Series and Systematic Review

Chronic subdural hematoma or nonacute subdural hematoma (NASH) remains a common neurosurgical disease, with an incidence of 1.7-20.6:100,000 individuals. Surgical evacuation of chronic subdural hematoma can be complicated by inadequate drainage and recurrence rates up to 20%-30% in some series. We examine the safety and efficacy of endoscope-assisted NASH evacuation and review the literature on the technique. A consecutive, single-center series of endoscope-assisted NASH evacuations was reviewed to assess patient factors, imaging, and recurrence. A systematic literature review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 9 patients who underwent endoscope-assisted NASH evacuation were included. This technique showed some improved evacuation of hematoma, removal of membranes, coagulation of at-risk blood vessels, directed placement of surgical drains, visualization of embolization efficacy, coagulation of friable membranes, and removal of acute clot. Only 1 episode of NASH recurrence (11.1%) was seen at the last follow-up. A systematic review of 14 studies with 1353 patients identified the use of membranectomy in 57% of cases and a recurrence rate of 0%-8.8%. Endoscopic visualization can be a useful adjunct in the modern treatment of NASH. Reduced risk of recurrence was seen compared with those of historical surgical drainage methods including burr holes (20-30%). The inclusion of endoscopic visualization in the modern era with middle meningeal artery embolization may potentially combine methods that can dramatically reduce the recurrence of NASH.

Real-Time (iOCT) Guided Epiretinal Membrane Surgery Using a Novel Forceps with Laser-Ablated Microstructure Tip Surface.

Purpose: We investigated intraoperative OCT (iOCT)—guided epiretinal membrane (ERM) and internal limiting membrane (ILM) removal using a novel forceps with a laser-ablated tip surface; it was designed to help prevent indentation force, shear stress, or tractional trauma when grasping very fine membranes. Patients and Methods: This retrospective study included patients who underwent 23- and 25-gauge pars plana vitrectomy (PPV) for vitreoretinal interface disorders. ERM and ILM peeling was performed under guidance with microscope-integrated iOCT using novel ILM forceps with laser-ablated tip surfaces. These forceps were engineered to enhance friction when grasping tissue. Evaluation of ERM/ILM manipulation included postoperative slow-motion video analysis of the number of grasping attempts, initial ILM mobilization, and observed damage to retinal tissue. Results: ERM/ILM removal was successfully performed in all patients, with an average of four grasp actions to initial membrane mobilization (91%). Additional use of a diamond-dusted membrane scraper was used in two cases (9%). Mean best-recorded visual acuity (BRVA) logMAR improved from 0.5 ± 0.34 to 0.33 ± 0.36 (p = 0.05) and mean central retinal thickness (CRT) improved from 462 ± 146 µm to 359 ± 78 µm (p = 0.002). Postoperative iOCT video analysis demonstrated hyper-reflectivity of the inner retinal layers associated with retinal hemorrhage in five eyes (22%), but no grasping-related retinal breaks. Conclusions: The texturized surface on the tips of the ILM forceps were found to be helpful for mobilizing ILM edges from the retinal surface. iOCT-guided ERM surgery also allowed for improved intraoperative tissue visualization. We believe that these two technologies helped reduce both unnecessary surgical maneuvers and retinal damage.

Post-Descemet's membrane endothelial keratoplasty Pseudomonas graft infection

To report evaluation and management of graft-host interface keratitis post-Descemet's membrane endothelial keratoplasty (DMEK). A 70-year-old lady with pseudophakic bullous keratopathy who underwent DMEK and developed interface interstitial keratitis on the first postoperative day. Cultures of corneal button revealed gram-negative bacilli (Pseudomonas aeruginosa). Prompt surgical intervention in the form of removal of donor Descemet's membrane and targeted antibacterial therapy helped in the complete resolution of infection. Descemet's stripping endothelial keratoplasty (DSEK) was performed postresolution of infection which yielded a good visual outcome for the patient. Donor rim culture helps immensely in identifying organisms in cases presenting in the early postoperative period.

Porcupine quills-like-structures containing smart PVDF/chitosan hybrids for anti-fouling membrane applications and removal of hazardous VOCs

The separation materials with enhanced transport and separation in membrane distillation (MD) and antifouling features were generated. The membranes were systematically characterized to understand how the covalent modification process, i.e., silanization and functionalization with chitosan, impacts the membrane performance. The material modification was done by the biomimicry of desert beetle (Stenocara gracilipes) armor and porcupine quills. The hydrophobic-hydrophilic structure of beetle armor was mimicked with the application of PVDF membrane as a hydrophobic surface and chitosan (CS) as hydrophilic nodes. By changing the experimental protocol, unique quill-like structure morphology was generated. The introduction of pristine and partially hydrophobized chitosan increased roughness significantly from 70 nm to 386 nm and 440 nm, causing contact angle improvement from 114.6° to 157.4° and 168.2°, respectively. Four times increment of transport was observed after adding CS. MD membranes with superior wetting resistance (critical surface tension ca. 20 mN m−1) were created by combining hierarchically structured membranes with re-entrant texture. The selection of fluorine-free modifiers allows the synthesis of environmentally friendly membranes and reduces the problem of bioaccumulation and acute toxicity occurring with long-chain fluorinated modifiers. Materials were tested in the air gap membrane distillation (AGMD) to remove hazardous volatile organic compounds from water. Data were analyzed by applying Hansen’s Solubility Parameters. Membranes were also applied for raw apple juice dewatering with fouling study during the osmotic MD process.

High−saline and long−term treatability of industrial wastewater by AnOMBR using organic and inorganic draw solutions

Less costly to AnMBR, anaerobic osmotic membrane bioreactor (AnOMBR) proceeds water and energy−efficient progresses within green and cleaner technologies. Long−term effectively operation of AnOMBR in high salinities due to salt accumulation is of the greatest priority, accompanied with a cost−performance efficient and non−inhibitory draw solution (DS) usage. Operational stability of AnOMBR in industrial wastewater treatment was studied at 30 mS/cm using the most favorable organic and inorganic DS within 29 DSs in our prior work, namely HCOONa and CaCl2. Osmotic and microbial yields during unintervented operations were lost due to severe salt stress and membrane biofouling. With a virgin membrane replacement, removal efficiencies, water and salt flux selectivity were partially restored, but the AnOMBRs turned towards collapse due to microbial activity lost. Therefore, sludge inoculation was applied and improved all AnOMBR performances to levels so close to before losses with 78 ± 3 % COD and 98.3 ± 0.6 % PO43-–P, 0.44 ± 0.2 L CH4/d excluding NH4+–N of 44 ± 10 %. It was designated that reverse salt passage for both the DS was responsible for approximately two-thirds of in-reactor salt build-up during stable AnOMBR operations. Statistical analysis results of the AnOMBR system for HCOONa and CaCl2 showed that statistical significances of performances in treatments with both DSs were from moderate to strong evidence levels. Microbial diversity increased by salt accumulation, and archaeal community differentiated. HCOONa promoted hydrogenotrophic halotolerant methanogenic archaeas, but not by CaCl2. Biofilm formed predominantly by biomass, Na+/Ca2+−bound biopolimers and inorganic precipitates provided bioactively better C, N, and P exhaustions in more porous and thicker secondary membrane layer by HCOONa. Beyond a virgin membrane replacement and sludge inoculation, an AnOMBR can be efficiently operated by sludge acclimation to high salinities, finest membrane clean-up, and even fabrication of FO membrane with the integrated nano-structured novel membranes such as including silver, nanofibers, graphene oxides etc.

Хирургическое лечение дегенеративного ламеллярного макулярного разрыва с применением богатой тромбоцитами плазмы крови

Introduction. Surgical treatment of patients with degenerative lamellar macular hole (LMH) does not always improve visual acuity. One of the risk factors for such results is pronounced thinning of the retina in the area of the hole. In such cases, it was suggested to supplement the standard surgical technique with the application of autologous platelet-rich blood plasma (PRP) to the area of the hole. Purpose. To present a clinical case of surgical treatment of degenerative LMH with pronounced retinal thinning using PRP. Material and methods. Patient C., 68 years old, complained of distortion of objects contours and decreased vision in the right eye. His corrected visual acuity was 0.4. Optical coherence tomography revealed a degenerative LMH (Govetto A. et al. classification, 2016) of the right eye with significant retinal tissue defect, with ellipsoidal photoreceptor zone defect and minimal retinal thickness of 59 μm. A three-port subtotal 27G vitrectomy was performed with removal of the epiretinal membranes and internal limiting membrane, tamponade of the vitreal cavity with air, and application of autologous PRP to the hole area. Results. The dynamics of retinal recovery in terms of up to 9 months after surgery is described, the minimum retinal thickness increased from 59 to 238 μm; the maximum corrected visual acuity increased from 0.4 to 1.0. The formation of a hyperreflective zone similar in optical density to plexiform layers was noted in the area where the hole had previously occurred. The size of the hyperreflective zone decreased during observation. By 9 months after surgery, the ellipsoidal zone defect was virtually undetectable. Conclusion. The use of PRP resulted in not only closure of the hole but also normal retinal thickness in the foveal area which contributed to the restoration of the ellipsoidal zone of the photoreceptors and a significant increase of visual acuity. Presumably, PRP contributes to the speedy closure of the hole due to the formation of a glial scar of minimal size. Key words: degenerative lamellar macular hole, platelet-rich blood plasma, vitrectomy, hyperreflective zone, glial scar

Optimising correlative super resolution and atomic force microscopies for investigating the cellular cytoskeleton

Correlative imaging methods can provide greater information for investigations of cellular ultra-structure, with separate analysis methods complementing each other's strengths and covering for deficiencies. Here we present a method for correlative applications of super resolution and atomic force microscopies, optimising the sample preparation for correlative imaging of the cellular cytoskeleton in COS-7 cells. This optimisation determined the order of permeabilisation and fixation, the concentration of Triton X-100 surfactant used and time required for sufficient removal of the cellular membrane while maintaining the microtubule network. Correlative SMLM/AFM imaging revealed the different information that can be obtained through each microscopy. The widths of microtubules and microtubule clusters were determined from both AFM height measurements and Gaussian fitting of SMLM intensity cross sections, these were then compared to determine the orientation of microtubules within larger microtubule bundles. The ordering of microtubules at intersections was determined from the AFM height profiles as each microtubule crosses the other. The combination of both microtubule diameter measurements enabled greater information on their structure to be found than either measurement could individually.

ABCA1 is an extracellular phospholipid translocase

Production of high density lipoprotein (HDL) requires ATP-binding cassette transporter A1 (ABCA1) to drive phospholipid (PL) from the plasma membrane into extracellular apolipoprotein A-I. Here, we use simulations to show that domains of ABCA1 within the plasma membrane remove PL from the membrane’s outer leaflet. In our simulations, after the lipid diffuses into the interior of ABCA1’s outward-open cavity, PL extracted by the gateway passes through a ring-shaped domain, the annulus orifice, which forms the base of an elongated hydrophobic tunnel in the transporter’s extracellular domain. Engineered mutations in the gateway and annulus strongly inhibit lipid export by ABCA1 without affecting cell-surface expression levels. Our finding that ABCA1 extracts lipid from the outer face of the plasma membrane and forces it through its gateway and annulus into an elongated hydrophobic tunnel contrasts with the alternating access model, which proposes that ABCA1 flops PL substrate from the inner leaflet to the outer leaflet of the membrane. Consistent with our model, ABCA1 lacks the charged amino acid residues in the transmembrane domain found in the floppase members of the ABC transporter family.

EFFECTS OF ECTOPIC INNER FOVEAL LAYERS ON FOVEAL CONFIGURATION AND VISUAL FUNCTION AFTER IDIOPATHIC EPIRETINAL MEMBRANE SURGERY.

To investigate the effects of ectopic inner foveal layers (EIFLs) on foveal configuration recovery and visual acuity after idiopathic epiretinal membrane removal and analyze the relationship of foveal configuration recovery between 1-month and long-term postoperatively. This retrospective study included 216 consecutive eyes with idiopathic epiretinal membrane that underwent vitrectomy surgery. A comprehensive ophthalmic examination was performed for all patients before and 1, 4, 10, and 24 months after surgery. We observed the postoperative anatomical and functional recovery of eyes with and without EIFLs and analyzed the association between short-term and long-term anatomical recovery. The presence of EIFL was associated with severe preoperative visual damage ( P < 0.001) and was considered as a negative factor for postoperative foveal depression recovery ( P < 0.001). No significant difference was found in postoperative best-corrected visual acuity between the eyes with and without EIFLs ( P = 0.442). For eyes with Stage II epiretinal membranes, 17.6% developed EIFLs postoperatively, which did not affect the final best-corrected visual acuity. Overall, 24.5% of epiretinal membranes restored the foveal configurations at 1 month postoperatively, and 14.7% continued recovering during the follow-up. Foveal structure recovery in eyes with EIFLs was associated with earlier stage, fewer microcystic macular edema, complete interdigitation zone layer, and a thinner central foveal thickness (all P < 0.05) at 1 month postoperatively. The EIFL is associated with severe preoperative visual damage and is a negative factor for postoperative anatomical recovery, but it is a minor factor for postoperative visual acuity. We also found an association of foveal configuration recovery between 1 month and long-term after surgery.

Extracellular Cysteines Are Critical to Form Functional Cx46 Hemichannels.

Connexin (Cxs) hemichannels participate in several physiological and pathological processes, but the molecular mechanisms that control their gating remain elusive. We aimed at determining the role of extracellular cysteines (Cys) in the gating and function of Cx46 hemichannels. We studied Cx46 and mutated all of its extracellular Cys to alanine (Ala) (one at a time) and studied the effects of the Cys mutations on Cx46 expression, localization, and hemichannel activity. Wild-type Cx46 and Cys mutants were expressed at comparable levels, with similar cellular localization. However, functional experiments showed that hemichannels formed by the Cys mutants did not open either in response to membrane depolarization or removal of extracellular divalent cations. Molecular-dynamics simulations showed that Cys mutants may show a possible alteration in the electrostatic potential of the hemichannel pore and an altered disposition of important residues that could contribute to the selectivity and voltage dependency in the hemichannels. Replacement of extracellular Cys resulted in “permanently closed hemichannels”, which is congruent with the inhibition of the Cx46 hemichannel by lipid peroxides, through the oxidation of extracellular Cys. These results point to the modification of extracellular Cys as potential targets for the treatment of Cx46-hemichannel associated pathologies, such as cataracts and cancer, and may shed light into the gating mechanisms of other Cx hemichannels.

Clinical Characteristics of the Eye with Fuch’s Corneal Endothelial Dystrophy after Descemet Stripping Only

Purpose: To report the effect of removal of a central descemet membrane on the endothelial function, morphology, and clinical symptoms of eyes with Fuch’s endothelial dystrophy.Methods: From August 2019 to January 2021, patients with Fuch’s endothelial dystrophy, i.e., with confluent, central corneal guttae and cataracts that required surgery, underwent phacoemulsification, intraocular lens implantation, and central descemet membrane stripping. To evaluate the effect of descemet stripping only (DSO), visual acuity and intraocular pressure were measured, and corneal pachymetry, slit-lamp and specular microscopy, and anterior segment optical coherence tomography performed, before surgery and at 1, 7, and 30 days and 3 and 6 months after surgery.Results: Seven patients (10 eyes) were included. Visual acuity improved from 1.01 ± 0.40 logarithm of the minimum angle of resolution (logMAR) preoperatively to 0.33 ± 0.22 logMAR 6 months after surgery (p = 0.008). The mean central corneal thickness decreased from 578.50 ± 36.88 μm preoperatively to 568.50 ± 48.61 μm 6 months after surgery; the difference was not significant (p = 0.507). The endothelial cell count increased significantly from 663.80 ± 356.40/mm2 preoperatively to 1,082.00 ± 274.46/mm2 6 months after surgery (p = 0.043).Conclusions: DSO can serve as a useful alternative when corneal transplantation is not possible in patients with Fuch’s endothelial dystrophy, but treatment efficacy and safety require further evaluation.

Chitosan-wrapped multi-walled carbon nanotubes (CS/MWCNT) as nanofillers incorporated into nanofiltration (NF) membranes aiming at remarkable water purification

Green process engineering, following the principles of the process intensification strategy, may make a significant contribution to industrial sustainability. Membrane-based separation and its potential have lately gained widespread recognition as assisting in the pursuit of these principles. Consequently, while focusing on a novel eco-friendly, cost-effective approach, we investigated the synergistic effect of incorporating multi-walled carbon nanotubes (MWCNTs) into the carbohydrate polymer chitosan (CS) on the nanofiltration performance of the mixed matrix polyethersulfone (PES) membranes to obtain highly decolorized water from licorice root extraction wastewater (LREW). To this end, following the optimization of pristine PES membranes in terms of their polymer concentrations and thicknesses, CS/MWCNT nanoparticles (0, 0.1, 0.5, and 1.0 wt%) were incorporated into the optimized matrix of pristine PES. Along with the physicochemical properties studied, water contact angle, pure water flux (PWF), color and COD removal, and antifouling properties were evaluated, with the 0.5 wt% CS/MWCNT achieving the highest permeate flux (~9.41 kg/m2·h) and color removal (~93 %). Ultimately, the long-term flux decline and color removal of the optimum membrane were evaluated using three different wastewater sources, shedding light on its promising future.

PROFILING CIRCULATING EXTRACELLULAR VESICLE SURFACE ANTIGENS IN PRIMARY ALDOSTERONISM

Objective: Primary aldosteronism (PA) is characterized by an inappropriate secretion of aldosterone. Chronic aldosterone excess exerts detrimental effects on cardiovascular system, including endothelial dysfunction and vascular inflammation. Circulating extracellular vesicles (EVs) are central players in the crosstalk between endothelium and inflammatory cells, and they may be involved in the development of organ damage in patients with PA. The aim of the present study was to assess the potential role of EVs in aldosterone-related vascular injury by evaluating a panel of 37 EV surface antigens through an innovative flow cytometry multiplex bead-based platform. Design and method: Serum EVs were isolated by immuno-capture from 32 patients with PA, 29 patients with essential hypertension (EH) and from 22 normotensive (NT) controls. EVs were characterized by nanoparticle tracking analysis, transmission electron microscopy, western blotting, and flow cytometry. Results: EV concentration was higher and diameter lower in patients with PA compared to patients with EH and NT controls and the number of particles decreased after unilateral adrenalectomy. Nineteen EV surface antigens were differentially expressed in patients with PA compared to patients with EH or NT controls, including markers from activated platelets, endothelial and immune/inflammatory cells. Supervised learning was used to combine the expression levels of EV surface markers in a specific molecular signature which discriminated patients with PA from controls (EH and NT), whereas after specific treatment the profile became similar to EH. Stimulation of human endothelial cells with PA patient-derived EVs, but not with EVs from EH, resulted in the overexpression of 5 selected genes (AKT1, CALR, CSNK2A1, FN1, and PIK3R1), previously identified by bioinformatics analysis as potential targets of differentially expressed EV antigens. Notably, the effect was specifically dependent on EV surface antigens, since it was abolished by removal of EV membrane associated proteins. The overexpression of CALR and FN1 was confirmed also at protein level. Conclusions: Our data suggest that EVs represent biomarkers of vascular inflammation and endothelial dysfunction in patients with PA, and also potential biovectors contributing to endothelial dysfunction, vascular inflammation, and accelerated organ damage by multiple signalling processes.

Confining Nano-Fe3O4 in the Superhydrophilic Membrane Skin Layer to Minimize Internal Fouling.

Membrane surface fouling is often reversible as it can be mitigated by enhancing the crossflow shear force. However, membrane internal fouling is often irreversible and thus more challenging. In this study, we developed a new superhydrophilic poly(vinylidene fluoride) (P-PVDF) membrane confined with nano-Fe3O4 in the top skin layer via reverse filtration to reduce internal fouling. The surface of the P-PVDF membrane confined with nano-Fe3O4 had superwetting properties (water contact angle reaching 0° within 1 s), increased roughness (from 182 to 239 nm), and enhanced water affinity. The Fe3O4@P-PVDF membrane surface showed a thicker and enhanced hydration layer, which prevented foulants from approaching membrane surfaces and pores, thereby improving the rejection. For example, when 50 ppm humic acid (HA) solution was used as the feed, the removal efficiency of the Fe3O4@P-PVDF membrane was ∼67%, while the HA removal of the P-PVDF membrane was only ∼20%. The results from the resistance-in-series model showed that nanoconfinement of Fe3O4 in the top skin layer of the membrane allowed foulants to accumulate on the membrane surface (i.e., surface fouling) rather than within the internal pores (i.e., internal fouling). The filtration results under crossflow fouling and cleaning confirmed that the Fe3O4@P-PVDF membrane had higher surface fouling but it was much more reversible and much lower internal fouling compared with the control membrane. Our fouling analysis offers new insights into mass transfer mechanisms of the membrane with a nanoconfinement-enhanced hydration layer. This study provides an effective strategy to develop membranes with low internal fouling propensities.

Factors Associated With Morbidity and Retreatment After Surgical Management of Nonacute Subdural Hematomas in Elderly Patients.

BackgroundPreoperative identification of clinical, radiographic, and surgery-specific factors associated with nonacute subdural hematomas (SDHs) may enable clinicians to optimize the efficacy of the initial surgical intervention, improve outcomes, and decrease rates of surgical recurrence.MethodsThe authors identified patients aged ≥65 years who underwent surgical treatment of chronic, subacute, or mixed-density SDH at a level-1 trauma hospital over a ten-year period (2010-2019). Pre-and postoperative clinical, radiographic, and surgery-specific data were collected. Predictors of surgical recurrence as well as morbidity, mortality, and discharge disposition were analyzed.ResultsThere were 268 nonacute SDHs treated surgically; 46 were chronic, 19 were subacute, and 203 were mixed density. Of these, 179 were treated with burr hole(s), 62 with miniature craniotomy, and 27 via a large craniotomy and removal of subdural membranes. Statin use was protective (OR 0.22; 95% CI 0.08, 0.60) against recurrence requiring reoperation. Preoperative use of antithrombotic agents was not significantly associated with increased recurrence requiring reoperation. Smaller preoperative hematoma thickness was associated with significantly lower mortality risk, whereas mixed-density hematomas, patient age, change in thickness after surgery, density, and presence of cisternal effacement were significantly associated with discharge disposition. Hematoma type was also associated with hospital and intensive care length of stay.ConclusionsOur experience suggests that, in elderly patients, premorbid statin usage is associated with lower recurrence rates and preoperative antithrombotic use does not affect recurrence when appropriately reversed before surgery. Patient age, preoperative thickness, and hematoma type contribute to postoperative outcomes such as discharge disposition and length of stay.

Optical Coherence Tomography Combined with Fluorescein Fundus Angiography under Intelligent Algorithm to Evaluate the Clinical Efficacy of Ranibizumab Combined with Panretinal Photocoagulation in the Treatment of Macular Edema of Diabetic Retinopathy Patients.

This study aimed at investigating the clinical effect of ranibizumab combined with panretinal photocoagulation in the treatment of macular edema in diabetic retinopathy (DR) patients. A parametric deformation model was constructed, and based on this, it was evaluated using optical coherence tomography (OCT) combined with fluorescein fundus angiography (FFA). 56 DR patients (80 eyes) who needed surgery were selected for OCT and FFA scanning, and 0.5 mg ranibizumab was administered intravitreal injection before surgery. It should observe the OCT and FFA image characteristics of patients. In addition, the vision correction status before the surgery, 1 month, 3 months, and 6 months after the surgery, the thickness of the macular retina, operation time, the number of intraoperative electrocoagulation, and complications of patients were recorded. It was found that 82.85% of patients had improved visual acuity after surgery. Compared with preoperative, the average logarithm of the minimum angle of resolution (logMAR) of patients at 6 months after surgery increased significantly (P < 0.01). With the increase of the grade of fibrosis and the grade of hemorrhage, the logMAR visual acuity recovery at 6 months after the surgery became worse; the macular retinal thickness at 6 months after the surgery decreased significantly (P < 0.01). With the increase of the grade of fibrous proliferation and the grade of bleeding, the operation time, the number of electrocoagulation, and the possibility of iatrogenic holes of patient would increase. It can be known that ranibizumab combined with panretinal photocoagulation surgery could not only reduce the macular edema but also effectively reduce the intraoperative bleeding, simplify the removal of proliferative membranes, decrease the number of electrocoagulation, and shorten the operation time, enhancing the visual function of patients.