ABSTRACT
BACKGROUND: In patients with symptomatic paroxysmal atrial fibrillation that has not responded to medication, catheter ablation is more effective than antiarrhythmic drug therapy for maintaining sinus rhythm. However, the safety and efficacy of cryoballoon ablation as initial first-line therapy have not been established. METHODS: We performed a multicenter trial in which patients 18 to 80 years of age who had paroxysmal atrial fibrillation for which they had not previously received rhythm-control therapy were randomly assigned (1:1) to receive treatment with antiarrhythmic drugs (class I or III agents) or pulmonary vein isolation with a cryoballoon. Arrhythmia monitoring included 12-lead electrocardiography conducted at baseline and at 1, 3, 6, and 12 months; patient-activated telephone monitoring conducted weekly and when symptoms were present during months 3 through 12; and 24-hour ambulatory monitoring conducted at 6 and 12 months. The primary efficacy end point was treatment success (defined as freedom from initial failure of the procedure or atrial arrhythmia recurrence after a 90-day blanking period to allow recovery from the procedure or drug dose adjustment, evaluated in a Kaplan-Meier analysis). The primary safety end point was assessed in the ablation group only and was a composite of several procedure-related and cryoballoon system-related serious adverse events. RESULTS: Of the 203 participants who underwent randomization and received treatment, 104 underwent ablation, and 99 initially received drug therapy. In the ablation group, initial success of the procedure was achieved in 97% of patients. The Kaplan-Meier estimate of the percentage of patients with treatment success at 12 months was 74.6% (95% confidence interval [CI], 65.0 to 82.0) in the ablation group and 45.0% (95% CI, 34.6 to 54.7) in the drug-therapy group (P<0.001 by log-rank test). Two primary safety end-point events occurred in the ablation group (Kaplan-Meier estimate of the percentage of patients with an event within 12 months, 1.9%; 95% CI, 0.5 to 7.5). CONCLUSIONS: Cryoballoon ablation as initial therapy was superior to drug therapy for the prevention of atrial arrhythmia recurrence in patients with paroxysmal atrial fibrillation. Serious procedure-related adverse events were uncommon. (Supported by Medtronic; STOP AF First ClinicalTrials.gov number, NCT03118518.).
Subject(s)
Anti-Arrhythmia Agents/therapeutic use , Atrial Fibrillation/drug therapy , Atrial Fibrillation/surgery , Catheter Ablation , Cryosurgery , Adult , Aged , Anti-Arrhythmia Agents/administration & dosage , Anti-Arrhythmia Agents/adverse effects , Catheter Ablation/adverse effects , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Quality of Life , Recurrence , Secondary Prevention/methods , Single-Blind Method , Surveys and QuestionnairesABSTRACT
PURPOSE: To report the outcomes of cataract surgery in patients with ocular graft-versus-host disease (oGVHD) using a novel preoperative immunomodulatory regimen in a collaborative subspecialty care setting. METHODS: Retrospective case series of patients with oGVHD who underwent cataract surgery using a novel preoperative immunomodulatory regimen in a collaborative care setting. A preoperative regimen consisting of pooled human immune globulin 1%, autologous serum 50%, and methylprednisolone 1% eye drops was prescribed. Outcome measures included visual acuity (VA), ocular surface disease index (OSDI) score, lissamine green staining, and complications with a minimum of 2 years of follow-up. RESULTS: Thirty-five eyes from 20 patients with oGVHD were studied. The mean age was 59 years (range 30-70 years). A healthy comparison group included 35 eyes from 24 patients with a mean age of 63 years (range 44-74 years). At the 2-year follow-up, the mean corneal staining score was 2.3/15, the mean OSDI score was 37.5, and the mean VA was 20/30 (logarithm of the minimal angle of resolution 0.17). The global complication rate was 2.8% at the last follow-up with no difference versus a healthy comparison group. CONCLUSIONS: A collaborative care model improving ocular surface health before cataract surgery with dry eye and cataract subspecialists can optimize outcomes in patients with oGVHD.
Subject(s)
Cataract Extraction , Cataract , Dry Eye Syndromes , Graft vs Host Disease , Humans , Adult , Middle Aged , Aged , Retrospective Studies , Graft vs Host Disease/complications , Cataract Extraction/adverse effects , Dry Eye Syndromes/complications , Cataract/complications , InflammationABSTRACT
PURPOSE: To analyze higher-order aberrations (HOAs) and their visual impact in a pediatric blepharokeratoconjunctivitis (PBKC) cohort compared with healthy controls. METHODS: Prospective case-control study of pediatric patients (≤ 16 years old). Subjects underwent wavefront aberrometry analysis to compare HOAs and their impact on visual quality. RESULTS: A total of 150 eyes from 76 patients were included in the analysis. The PBKC group consisted of 50 eyes and the control group of 100 healthy eyes. Mean age was 10.39 ± 3.81 years for the PBKC group and 10.80 ± 3.61 years for the controls. Mean corrected-distance visual acuity (CDVA) was 0.24 ± 0.21 logMAR in the PBKC group and 0.07 ± 0.1 in the controls (P < 0.001). Mean astigmatism was 1.6 ± 1.98D in the PBKC group vs. 0.67 ± 0.76D in the control group (P = 0.01). Mean RMS of HOAs was 1.05 ± 1.7mm in the PBKC group and 0.41 ± 0.18mm in the controls (P < 0.001). The mean modulation transfer function (MTF) in the PBKC group was significantly lower (16.37 ± 16.32) than controls (30.3 ± 23.57) (P < 0.001). Corneal leukomas, stromal vascularization, peripheral nummular subepithelial scars, and pannus formation are associated with increased HOAs. CONCLUSIONS: There was a significant increase in total HOAs of eyes with PBKC compared to healthy controls. Corneal opacity, vascularization, and scarring are associated with increased HOAs. The PBKC eye aberration profile: coma, secondary astigmatism, quadrafoil, and pentafoil, were associated with decreased CDVA and visual quality (PSF and MTF).
Subject(s)
Astigmatism , Corneal Opacity , Corneal Wavefront Aberration , Humans , Child , Adolescent , Case-Control Studies , Visual Acuity , Cornea , Refraction, OcularABSTRACT
PURPOSE: Actinic conjunctivitis (AC), along with cheilitis (AChe), is part of the clinical spectrum of actinic prurigo (AP), a rare photo dermatosis that affects high-risk populations. We analyzed the clinical manifestations and onset of actinic conjunctivitis (AC), and its relationship with prurigo (AP) in a susceptible population. METHODS: This prospective observational cohort study was performed on Indigenous populations from the highlands of Chiapas, Mexico. Thorough dermatological and ophthalmological examinations were performed in patients attending a primary health care center. The clinical features, labor and environmental factors, onset timing, and clinical staging of AC and AP were analyzed. RESULTS: Of the 2913 patients studied, 54 patients (108 eyes) (1.8%) had AC, and 14 patients (25.9%) had AP. The mean age at diagnosis was 36.18 ± 18.52 years (6-70 years). The mean residential altitude was 1884 ± 434.2 m above sea level. Mean self-reported sun exposure was 5.14 ± 3.1 h a day (0.5-12 h). A total of 90.7% reported exposure to biomass fuels during cooking, and 50% to farm animals. AC was the sole manifestation in 70% of the cases. All patients had nasal and temporal photo-exposed conjunctiva. Among the eyes, 12.9% were classified as stage-1, 64.8% as stage-2, and 22.2% stage-3. A total of 83.3% of the patients had hyperpigmented lesions, and 35.1% had evaporative dry eye disease. CONCLUSIONS: AC may be the initial or sole manifestation of AP. Most AC cases (87%) were initially observed at the advanced stages of the disease. Although solar exposure was not associated with late AC stages, a positive association was found with farm animal exposure. Evaporative dry eye associated with meibomian gland dysfunction has not been previously reported in patients with AC.
Subject(s)
Conjunctivitis , Photosensitivity Disorders , Prurigo , Skin Diseases, Genetic , Animals , Humans , Adolescent , Young Adult , Adult , Middle Aged , Mexico/epidemiology , Prurigo/complications , Prurigo/epidemiology , Prurigo/pathology , Prospective Studies , Indigenous PeoplesABSTRACT
PURPOSE: To evaluate the association between LASIK and early cataract phacoemulsification surgery (PE). METHODS: A matched case-control study was conducted. Cases were otherwise healthy adults with a history of LASIK. Groups were paired according to corrected-distance visual acuity (CDVA), axial length, and cataract grade. RESULTS: A total of 213 patients were included. 85 patients were classified as post-LASIK group and 128 as controls. The mean age at the time of LASIK was 42.32 ± 9.24 years. The mean CDVA before PE was 0.29 ± 0.19 Log MAR in post-LASIK group and 0.34 ± 0.22 Log MAR in controls (p = 0.07). The mean axial length was 23.99 ± 1.78 mm in post-LASIK group and 23.62 ± 0.98 mm in controls (p = 0.085). The mean nuclear cataract grading was 1.36 in post-LASIK group and 1.47 in controls (p = 0.34). The mean age at the time of PE was 60.18 ± 7.46 years in post-LASIK group and 67.35 ± 9.28 in controls (p < 0.0005). The difference between the mean age of LASIK and the mean age of PE was 17.85 ± 5.72 years. There was a positive association between the post-LASIK group and the age of PE ≤ 55 years (OR: 4.917, 95% CI: 2.21-10.90, p < 0.001). CONCLUSION: LASIK may be associated with early PE. Patients with LASIK had a 7-year earlier PE compared to a matched control group.
Subject(s)
Cataract Extraction , Cataract , Keratomileusis, Laser In Situ , Phacoemulsification , Adult , Humans , Child , Adolescent , Young Adult , Middle Aged , Case-Control Studies , Cataract/complicationsABSTRACT
PURPOSE: The present review will summarize FECD-associated genes and pathophysiology, diagnosis, current therapeutic approaches, and future treatment perspectives. METHODS: Literature review. RESULTS: Fuchs' endothelial corneal dystrophy (FECD) is the most common bilateral corneal dystrophy and accounts for one-third of all corneal transplants performed in the US. FECD is caused by a combination of genetic and non-heritable factors, and there are two types: early-onset FECD, which affects individuals from an early age and is usually more severe, and late-onset FECD, which is more common and typically manifests around the age of 40. The hallmark findings of FECD include progressive loss of corneal endothelial cells and the formation of focal excrescences (guttae) on the Descemet membrane. These pathophysiological changes result in progressive endothelial dysfunction, leading to a decrease in visual acuity and blindness in later stages. The present review will summarize FECD-associated genes and pathophysiology, diagnosis, current therapeutic approaches, and future treatment perspectives. CONCLUSION: With the characterization and understanding of FECD-related genes and ongoing research into regenerative therapies for corneal endothelium, we can hope to see more significant improvements in the future in the management and care of the disease.
Subject(s)
Corneal Transplantation , Fuchs' Endothelial Dystrophy , Humans , Fuchs' Endothelial Dystrophy/diagnosis , Fuchs' Endothelial Dystrophy/genetics , Fuchs' Endothelial Dystrophy/therapy , Endothelial Cells , Endothelium, Corneal , BlindnessABSTRACT
AIMS: Cardioversion is a very commonly performed procedure for persistent atrial fibrillation (AF). However, there is no well-defined protocol to address failed external electrical direct current cardioversion. The aim of the study is to test the efficacy of a pre-defined stepwise cardioversion protocol for patients with persistent AF of ≤12 months. Success was the achievement of sinus rhythm. METHODS AND RESULTS: The study population included patients with persistent AF of ≤12 months duration requiring rhythm management. Patients were offered cardioversion using a pre-defined stepwise protocol using different electrode placement locations, applying compression at end of expiration, and higher energy delivered simultaneously through two defibrillators. : A total of 414 patients were included in the study, of which 362 (87.4%) required a single successful cardioversion. The remaining 52 (12.5%) patients required additional cardioversion attempts using the stepwise cardioversion protocol with an overall success rate of 99.3%. Two simultaneous defibrillators were required in 14 patients (3.4%). Patients with multiple cardioversions (13.5%) experienced more local skin irritation and pain compared with patients with single cardioversion (13.5% vs. 3.5%, P = 0.004). The predictor for the need for multiple cardioversion attempts is high body mass index, while high transthoracic impedance is associated with failed cardioversion. No major complications were observed during the study. CONCLUSION: The stepwise cardioversion protocol has a high success rate of >99% and can be safely performed in outpatient or inpatient settings.
Subject(s)
Atrial Fibrillation , Humans , Atrial Fibrillation/diagnosis , Atrial Fibrillation/therapy , Electric Countershock/adverse effects , Electric Countershock/methods , Treatment Outcome , Body Mass Index , RecurrenceABSTRACT
BACKGROUND: Durable electrical isolation of pulmonary veins (PVs) is associated with better outcomes after atrial fibrillation (AF) ablation, but previous studies of AF recurrence have reported high rates of reconnection despite successful acute isolation. This study aims to quantify historical trends in the durability of PV isolation (PVI) as radiofrequency (RF) ablation catheters, additional ablation technologies, and associated workflows have evolved. METHODS: The study population included adult patients receiving a first repeat ablation for AF between September 2013 and July 2019 at the study site. All index ablations were performed at the same site with an RF catheter and included PVI. Three generations of irrigated RF catheters based on the same technology platform were used by the site during the timeframe of this study. RESULTS: A total of 224 patients were included in the analysis. At repeat ablation, the mean number of patients with at least one reconnected PV dropped significantly with subsequent catheter generation, from 78.3% to 56.7% to 27.0% (p < .0001). Moreover, the mean number of reconnected PVs were significantly reduced from 1.48 to 0.92 to 0.47 (p < .0001), representing a 68.3% reduction across the 3 generations of devices. CONCLUSION: Significant improvement in durable PVI was seen with successive generations of RF catheter over a 6-year period. In addition to catheter technology, ancillary advances in ablation technologies, workflows, and operator experience likely contributed to these improvements.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Pulmonary Veins , Adult , Humans , Pulmonary Veins/surgery , Treatment Outcome , Time Factors , RecurrenceABSTRACT
Community-based organizations (CBOs) deliver services in culturally-responsive ways, and could effectively partner with health centers to deliver HIV pre-exposure prophylaxis (PrEP) to Latino men who have sex with men (LMSM). However, few such models exist. We conducted a planning study in collaboration with three CBOs serving LMSM to identify optimal PrEP delivery strategies for health centers and CBOs to implement jointly. We established a Community Expert Panel (CEP) of eight client-facing CBO and health center staff. Over 6 months, the panel met monthly to identify collaborative strategies for PrEP delivery, using a modified Delphi method consisting of the following steps: (1) brainstorming strategies; (2) rating strategies on acceptability, appropriateness and feasibility; (3) review of data from qualitative focus group discussions with CBO clients; and (4) final strategy selection. The panel initially identified 25 potential strategies spread across three categories: improving communication between health centers and CBOs; using low-barrier PrEP options (e.g. telemedicine), and developing locally-relevant, culturally-sensitive outreach materials. Focus groups with CBO clients highlighted a desire for flexible options for PrEP-related care and emphasized trust in CBOs. The final package of strategies consisted of: (1) a web-based referral tool; (2) telemedicine appointments; (3) geographically-convenient options for lab specimen collection; (4) tailored print and social media; and (5) regular coaching sessions with CBO staff. Through a community-engaged process, we identified a package of PrEP delivery strategies that CBOs and health centers can implement in partnership, which have the potential to overcome barriers to PrEP for LMSM.
Subject(s)
Anti-HIV Agents , HIV Infections , Pre-Exposure Prophylaxis , Humans , Male , Anti-HIV Agents/therapeutic use , Community Health Centers , Consensus , Focus Groups , Hispanic or Latino , HIV Infections/prevention & control , HIV Infections/drug therapy , Homosexuality, MaleABSTRACT
PURPOSE: Prostaglandin analogs (PGAs) are first-line treatments for ocular hypertension (OHT) and open-angle glaucoma (OAG). However, frequent side effects and high costs hinder patient's compliance resulting in disease progression. Evidence suggests selective laser trabeculoplasty (SLT) may be considered a first-line treatment for OHT and OAG due to its safety profile, minor side effects, and reduced costs. Considering that PGAs and SLT share action mechanisms, it is hypothesized that previous PGA therapy may affect subsequent SLT efficacy. Therefore, we analyzed if PGAs reduce SLT efficacy. METHODS: An evidence-based review was performed to assess the safety and efficacy of SLT in patients previously treated with PGAs. For this purpose, we performed an extensive literature search using the National Library of Medicine's PubMed and Google Scholar database for all English language articles published until May 2021. RESULTS: There is evidence of non-superiority of PGAs therapy versus SLT for OHT and OAG. A multicenter, randomized, observer-masked clinical trial (RCT) of untreated OHT and OAG patients concluded that SLT should be offered as the first-line treatment for these patients. This study was supported by a meta-analysis of RCTs, comparing SLT efficacy versus antiglaucoma drugs only, with the advantage of an SLT lower rate of adverse effects. CONCLUSIONS: Cost-effectiveness, patient compliance, and antiglaucoma drugs' side effects, including higher surgical failure, favor consideration of SLT as first-line therapy for OAG and OHT. Furthermore, SLT efficacy does not seem to be affected by prior PGA administration; however, larger cohort, comparative, multicenter RCTs are necessary to answer this question.
Subject(s)
Glaucoma, Open-Angle , Glaucoma , Laser Therapy , Ocular Hypertension , Trabeculectomy , Humans , Trabeculectomy/methods , Intraocular Pressure , Antiglaucoma Agents , Antihypertensive Agents/therapeutic use , Glaucoma/surgery , Ocular Hypertension/drug therapy , Ocular Hypertension/surgery , Prostaglandins, Synthetic/therapeutic use , Laser Therapy/methods , Lasers , Treatment Outcome , Randomized Controlled Trials as Topic , Multicenter Studies as TopicABSTRACT
INTRODUCTION: Contact force (CF) guided ablation of paroxysmal atrial fibrillation (PAF) with stable catheter-tissue contact optimizes clinical success and may increase an operator's ability to achieve pulmonary vein isolation (PVI) in a single encirclement. First pass PVI reduces procedure time but the relationship with long term clinical success is not well understood. This study evaluated patient characteristics and procedural details as predictors of 1-year clinical success after PAF ablation, including first pass isolation. METHODS: Consecutive de novo PAF ablations were performed with a porous tip CF catheter in 2017 and 2018. All ablations used wide-area circumferential ablation, with first pass isolation captured separately for the left and right pulmonary veins (PVs). CF was held between 10 and 20 g and the catheter was moved every 10-20 s. Radiofrequency energy was set at 40-45 W throughout the atrium. Patient characteristics and procedural details were tested for association with clinical success, defined as freedom from recurrent atrial tachyarrhythmia through 1 year. RESULTS: A total of 404 patients were included in the study. Clinical success at 1 year was 86.6%. Achieving first pass isolation on at least one ipsilateral PV pair was the most significant predictor of clinical success (p = .0126). After controlling for first pass isolation, only recurrence within the 90-day blanking period was independently predictive (p = .0015). First pass isolation was not associated with early recurrence (p = .2454). CONCLUSION: In a real-world setting, first pass isolation was highly predictive of 12-month clinical success after CF-guided ablation in a PAF population.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Pulmonary Veins , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Catheter Ablation/adverse effects , Heart Atria , Humans , Pulmonary Veins/surgery , Recurrence , Treatment OutcomeABSTRACT
The aim of the present study was to obtain an effective vehiculation system in which bacterial agents could maintain viability improving their removal capacity. Herein, we present a novel biohybrid membrane of polymeric nanofibers and free-living bacteria for the simultaneous removal of pollutants. In this system, bacteria are free within the pores between the nanofibers and adsorbed to the surface of the membranes. Association between bacteria and the membranes was performed through a self-formulated medium, and the presence of the bacteria in the polymeric matrix was evidenced through atomic force microscopy (AFM). Biohybrid membranes associated with the remediation agents Bacillus toyonensis SFC 500-1E and Acinetobacter guillouiae SFC 500-1A promoted a reduction of up to 2.5 mg/L of hexavalent chromium and up to 200 mg/L of phenol after 24 h of treatment in synthetic medium containing the contaminants. Similarly, more than 46% of the hexavalent chromium and all of the phenol content were removed after treatment of a tannery effluent with initial concentrations of 7 mg/L of Cr(VI) and 305 mg/L of phenol. Counts of the remediation agents from the membranes were always above 1.107 CFU/g, also in the reutilization assays performed without reinoculation. Biohybrid membranes were hydrolysis-resistant, reusable, and effective in the simultaneous removal of contaminants for more than 5 cycles. Viability of the microorganisms was maintained after long-term storage of the membranes at 4 °C, without the use of microbiological media or the addition of cryoprotectants. Graphical abstract KEY POINTS: ⢠Polymeric membranes were effectively associated with the SFC 500-1 remediation consortium ⢠Biohybrid membranes removed hexavalent chromium and phenol from different matrices ⢠Removal of contaminants was achieved in many successive cycles without reinoculation.
Subject(s)
Chromium , Phenol , Acinetobacter , Bacillus , Bacteria , Biodegradation, Environmental , PhenolsABSTRACT
BACKGROUND: Most atrial fibrillation (AF) ablations are performed with general anesthesia (GA). The ideal GA protocol is unknown, but it affects ablation outcomes and laboratory utilization. We sought to report a GA protocol used at a high-volume center, with special consideration on efficiency and optimization of mapping and ablation conditions. METHODS: Our protocol consists of propofol as sole anesthetic agent and analgesia with Fentanyl. IV fluids are minimized. After transseptal access, the right phrenic nerve is tagged, rocuronium is given, and redosing avoided. Ventilation is modulated to optimize mapping and ablation. After ablation, isoproterenol is infused for 20 min. After 10 min, propofol is gradually decreased and ventilation set to SIMV 8 breaths/min to promote spontaneous breathing, and then switched to pressure support and propofol stopped. Paralysis is reversed and furosemide given. Patient is extubated once meeting standard criteria. RESULTS: A total of 1286 patients underwent AF ablation from January 2017 to December 2018 using the protocol. Mean age was 66 years (41% paroxysmal AF, CHADS2Vasc 2.6). Total procedure time was 86 min. Median time to extubation was 9 min (first and third quartile 6-16) after procedure completed, with total anesthesia time of 116 min. On average 370 mL of fluids were given by anesthesia. Only one patient who had heart failure required reintubation with no other anesthesia-related complications seen. CONCLUSION: Our GA protocol was specifically designed for AF ablation. It was safe and led to efficient recovery and extubation times. It maximizes laboratory utilization time without compromising safety.
General anesthesia (GA) has been shown to improve outcomes of atrial fibrillation (AF) ablation. However, the ideal anesthetic protocol is unknown. We describe a GA protocol developed by the anesthesiology and electrophysiology team. It considers each phase of the ablation procedure separately in choosing drugs to be used and also careful modulation of ventilator settings to improve mapping and ablation conditions. This GA protocol was then utilized in 1286 patients undergoing AF ablation and it was safe and produced very efficient median time to extubation (9 min).
Subject(s)
Anesthesia, General , Anesthetics, Intravenous , Atrial Fibrillation/surgery , Catheter Ablation , Clinical Protocols/standards , Propofol , Aged , Cardiac Surgical Procedures/methods , Female , Humans , Male , Middle Aged , Retrospective StudiesABSTRACT
Bacillus sp. SFC 500-1E, a bacterial strain isolated from tannery sediments, is able to remove Cr(VI) and simultaneously tolerate high concentrations of phenol. In this study, we used high-resolution microscopies, fluorescence polarization techniques, and several biochemical approaches to improve our understanding about the adaptive mechanisms of this strain to survive in the presence of Cr(VI) and phenol, both individually and simultaneously. Among adaptive strategies developed by Bacillus sp. SFC 500-1E, an increase in bacterial size, such as length, width, and height, and ultrastructural alterations, such as electron-dense precipitates, the presence of exopolymers, and cell lysis, are noteworthy. The exopolymers observed were consistent with the extensive biofilm formation and exopolysaccharides and extracellular protein quantification. At the cell membrane level, a rapid rigidity was induced in Cr(VI) + phenol treatment. This effect was counteracted after 16 h by changes at the level of phospholipids, mainly in the composition of fatty acids (FAs); in particular, an increase in the unsaturated fatty acid/saturated fatty acid ratio was detected. This study shows evidence of some adaptive responses displayed by Bacillus sp. SFC 500-1E, which allows it to survive in stressful conditions.
Subject(s)
Bacillus/cytology , Bacillus/drug effects , Chromium/pharmacology , Phenol/pharmacology , Bacillus/metabolism , Biodegradation, Environmental , Biofilms/drug effects , Biofilms/growth & development , Cell Membrane/drug effects , Cell Membrane/physiology , Cell Membrane/ultrastructure , Chromium/metabolism , Extracellular Polymeric Substance Matrix/metabolism , Fatty Acids/chemistry , Phospholipids/chemistry , Stress, PhysiologicalABSTRACT
Bacterial surface molecules are crucial for the establishment of a successful rhizobia-legume symbiosis, and, in most bacteria, are also critical for adherence properties, surface colonization, and as a barrier for defense. Rhizobial mutants defective in the production of exopolysaccharides (EPSs), lipopolysaccharides (LPSs), or capsular polysaccharides are usually affected in symbiosis with their plant hosts. In the present study, we evaluated the role of the combined effects of LPS and EPS II in cell-to-cell and cell-to-surface interactions in Sinorhizobium meliloti by studying planktonic cell autoaggregation, biofilm formation, and symbiosis with the host plant Medicago sativa. The lpsB mutant, which has a defective core portion of LPS, exhibited a reduction in biofilm formation on abiotic surfaces as well as altered biofilm architecture compared with the wild-type Rm8530 strain. Atomic force microscopy and confocal laser microscopy revealed an increase in polar cell-to-cell interactions in the lpsB mutant, which might account for the biofilm deficiency. However, a certain level of biofilm development was observed in the lpsB strain compared with the EPS II-defective mutant strains. Autoaggregation experiments carried out with LPS and EPS mutant strains showed that both polysaccharides have an impact on the cell-to-cell adhesive interactions of planktonic bacteria. Although the lpsB mutation and the loss of EPS II production strongly stimulated early attachment to alfalfa roots, the number of nodules induced in M. sativa was not increased. Taken together, this work demonstrates that S. meliloti interactions with biotic and abiotic surfaces depend on the interplay between LPS and EPS II.
Subject(s)
Bacterial Proteins/metabolism , Biofilms/growth & development , Gene Expression Regulation, Bacterial/physiology , Mannosyltransferases/metabolism , Sinorhizobium meliloti/genetics , Sinorhizobium meliloti/physiology , Bacterial Adhesion , Bacterial Proteins/genetics , Mannosyltransferases/genetics , MutationABSTRACT
BACKGROUND: Subcutaneous implantable cardioverter defibrillators (S-ICDs) have gained increasing popularity because of certain advantages over transvenous ICDs. However, while conventional ICDs require a single surgical incision to implant, S-ICDS need two or three incisions, making them less appealing. OBJECTIVE: This study sought out to investigate the feasibility of using a single-incision technique to implant S-ICDs. METHODS: Patients qualifying for S-ICDs were considered for a single incision. A single incision is performed by making a left inframammary incision and then the subcutaneous tissue is dissected medially toward the lower sternum. Two sutures are placed in the fascia in the xiphoid area to anchor the lead and a tunneling tool is used to dissect the tissue to place the lead parallel to the sternum. Then subcutaneous tissues are dissected down the lateral chest wall over the muscle fascia to create the pulse generator pocket in the vicinity of the fifth and sixth intercostal spaces and near the mid-axillary line. RESULTS: Eleven patients (six males and five females) successfully underwent S-ICD implantation with a single incision without acute complications (64% for primary prevention). The mean age is 47.4 ± 15.8 years. There were no lead dislodgements, inappropriate shocks, or any other issues during a median follow-up of 10 months (interquartile range 5-17). One patient had a successful appropriate shock for ventricular fibrillation about one year after device implant. CONCLUSIONS: A single incision for subcutaneous ICDs is feasible and safe in our early experience.
Subject(s)
Defibrillators, Implantable , Prosthesis Implantation/methods , Feasibility Studies , Female , Humans , Male , Middle Aged , Patient Selection , Surgical Instruments , Suture Techniques , Treatment OutcomeABSTRACT
BACKGROUND: Ablation is an effective treatment for atrioventricular nodal reentrant tachycardia (AVNRT). The occurrence of junctional ectopic rhythm (JER), including junctional ectopic tachycardia, following AVNRT ablation has been described as an extremely rare phenomenon, but may be underestimated. We aimed to determine the incidence of JER following AVNRT ablation within our institution, as well as that reported in the literature via an extensive review. METHODS: We reviewed our adult ablation institutional experience for the occurrence of JER after AVNRT ablation from 2009 to 2016. Additionally, we conducted an extensive literature search using different databases looking for AVNRT ablation case series. The individually reported complications of these studies were reviewed, with a primary endpoint defined as the occurrence of JER shortly after AVNRT ablation. The study was approved by our institutional review board. RESULTS: Our institutional data revealed 6/126 patients (prevalence 4.8%) developed non-preexisting JER post-AVNRT ablation. Four patients were asymptomatic. Two patients had persistent symptoms lasting over a year, with one patient requiring repeat ablation. The literature review included 149 adult and pediatric studies. There were three cases of reported JER, out of a total of 37,541 patients (31,768 adults and 5,773 pediatric; prevalence 0.008%). The three JER patients were pediatric, and all required further therapeutic intervention. CONCLUSION: JER might be an underreported complication of AVNRT ablation. It seems most often to be transient and self-limited, occurring days to weeks after ablation, but may also be debilitating, requiring more aggressive management.
Subject(s)
Catheter Ablation/methods , Postoperative Complications/epidemiology , Tachycardia, Atrioventricular Nodal Reentry/epidemiology , Tachycardia, Ectopic Junctional/surgery , Adolescent , Adult , Comorbidity , Electrocardiography , Female , Humans , Male , Middle Aged , Prevalence , Risk FactorsABSTRACT
A variable-gain controller for anaerobic digestion of industrial winery wastewater is presented. A control law using both volatile fatty acids (VFA) and methane production rate as controlled variables and organic loading rate (OLR) as manipulated variable is defined. The process state is quantitatively estimated by an empirical function comparing VFA measurements against a setpoint value; then, it is modified with a second empirical function that compares the methane flow rate with a maximum capacity reference, and finally it is adjusted with a third factor considering the actual hydraulic retention time. The variable-gain function determines the extent of the OLR change applied to the system. The controller was successfully validated in a 95 L upflow-anaerobic-sludge-blanket (UASB) reactor, treating industrial wine wastewater at OLR ranged between 2.0 and 39.2 g COD/L d for 120 days at mesophilic conditions. Higher performance was achieved contrasted with a conventional strategy carried out in a parallel UASB unit.
Subject(s)
Fatty Acids, Volatile/analysis , Waste Disposal, Fluid/methods , Wine , Anaerobiosis , Bioreactors , Industrial Waste , Methane , Sewage , WastewaterABSTRACT
BACKGROUND: Dormant conduction unmasked by adenosine predicts clinical recurrences of cavotricuspid isthmus (CTI) dependent atrial flutter following catheter ablation. Conventional practice involves a waiting period of 20 to 30 minutes after achievement of a bidirectional line of block (BDB) to monitor for recovery of conduction. OBJECTIVE: Assess whether abolition of dormant conduction with adenosine immediately after CTI ablation and BDB can predict the lack of CTI conduction recovery during the following 30 minutes. METHODS: Consecutive patients undergoing catheter ablation for CTI-dependent atrial flutter were studied. Following the completion of CTI ablation and documentation of BDB, adenosine (≥12 mg IV) was administered immediately. In cases of dormant conduction, the CTI was ablated again until its abolition. After the achievement of BDB without dormant conduction, spontaneous CTI reconnection during the following 30 minutes and dormant conduction with adenosine at 30 minutes were evaluated. RESULTS: A CTI block was achieved in 171 patients. Nine patients (5.3%) had dormant conduction across the CTI immediately after ablation and BDB, and required further ablation. Two patients (1.2%) had subsequent spontaneous time-dependent reconnection within 30 minutes. Two other patients (1.2%) developed late dormant conduction with adenosine at 30 minutes. All 4 patients underwent further ablation. CONCLUSION: A negative adenosine challenge immediately after CTI ablation with bidirectional block, or after abolition of dormant conduction with further ablation, strongly predicted the absence of subsequent spontaneous reconnection within 30 minutes. Based on these results, the conventional waiting period is unnecessary in 97.6% patients without dormant conduction after CTI-dependent flutter ablation.
Subject(s)
Adenosine/administration & dosage , Atrial Flutter/diagnostic imaging , Atrial Flutter/therapy , Catheter Ablation/methods , Tricuspid Valve/diagnostic imaging , Aged , Atrial Flutter/physiopathology , Female , Follow-Up Studies , Heart Block/chemically induced , Heart Block/diagnostic imaging , Heart Block/physiopathology , Heart Conduction System/diagnostic imaging , Heart Conduction System/drug effects , Heart Conduction System/physiopathology , Humans , Male , Middle Aged , Time Factors , Tricuspid Valve/drug effects , Tricuspid Valve/physiopathologyABSTRACT
BACKGROUND: Implantable cardioverter-defibrillator (ICD) shocks are potentially associated with myocardial injury, altered hemodynamics, apoptosis, and inflammatory signaling. Their precise cellular impact can be explored after defibrillation testing (DFT) via biomarkers. We evaluated changes in biomarkers after ICD shocks during DFT. METHODS: We prospectively enrolled outpatients presenting for first implantation of a cardiac device. Biomarkers indicative of myocardial injury, inflammation, and apoptosis were measured before and after implantation, and compared between patients receiving DFT (DFT+) to those not (DFT-). RESULTS: Sixty-three patients were enrolled, 40 in the DFT+ group and 23 in the DFT- group. Average levels of troponin I, hsCRP, Calprotectin, N-terminal pro B-type natriuretic peptide (NTproBNP), and sFas increased by >50% after cardiac device implantation compared to baseline. Increase in troponin never exceeded the 50-fold upper limit of normal (2 ng/mL). Troponin trended higher in the DFT+ group at 8 hours (median 0.18 ng/mL, interquartile range [IQR] 0.11-0.48) versus the DFT- group (0.10 ng/mL, IQR 0.06-0.28, P = 0.0501); NTproBNP had a similar trend (P = 0.0581). sFas significantly increased in the DFT+ group from baseline (median 4663 pg/mL, IQR 2908-5679) to 24 hours (5039 pg/mL, IQR 3274-6261; P = 0.0338) but not in the DFT- group (P = 0.4705). CONCLUSION: DFT testing is associated with acutely increased plasma levels of troponin and sFas, a biomarker of apoptosis, along with a trend toward higher NTproBNP.