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Mahmoud Houmsse

and 1 more

Reply to “Additional Data Protection of the Esophagus During Catheter Ablation of Atrial Fibrillation”Mahmoud Houmsse, MD, and Emile G. Daoud, MDDepartment of Medicine, Division of Cardiology, Richard M. Ross Heart HospitalThe Ohio State University Medical Center, Columbus, OHRunning Title: Protection of EsophagusAddress for correspondence: Emile Daoud, MDDHLRI 473 W. 12th Avenue, Suite 200 Columbus, OH 43210-1252 Telephone: 877-478-2478 FAX : 614-293-5614E-Mail: emile.daoud@osumc.eduFunding: NoneDisclosure: Emile Daoud and The Ohio State University have equity ownership and serve as consultants to S4 Medical Corp, which is manufacturing the Esoultion esophageal retractor.Disclosure: Mahmoud Houmsse has no conflict of interestWe Thank Dr.Clark and Dr. Kulstad for their interest in our recent review manuscript “protection of the esophagus during catheter ablation of atrial fibrillation”We agree with Dr. Clark and Dr. Kulstad that utilization of luminal esophageal temperature (LET) monitoring during atrial fibrillation ablation is inadequate method to avoid esophageal injury. These have been reported in multiple studies that were referenced in our manuscript. The newer published studies regrading monitoring LET during atrial fibrillation ablation, which were reported by Dr. Clark and Dr. Kulstad, have been published during our manuscript publication process. Nevertheless, these studies that reported by Dr. Clark and Dr. Kulstad showed same conclusion of inadequate LET monitoring in preventing esophageal injury 1-3.Regarding active cooling, Dr. Clark and Dr. Kulstad reported recent published studies. First study small pilot study that showed active cooling is much more protective than manual liquid instillation4. The second pilot RCT that compared LET and active cooling showed same outcome like the IMPACT study that we reported in our manuscript 5,6.We agree with Dr. Clark and Kulstad, growing interest in the area of esophageal protection during atrial fibrillation ablation.We do believe, as we stated in the conclusion of our manuscript, that “a reliable method to protect the esophagus is of clinical value, but the ancillary value of reducing physician concern during AF ablation, reducing interruption to ablation work flow, perhaps enhancing AF ablation results and simplifying post procedure management of patient symptoms are also of high importance. Considering the ease of use, minimal side effects, and low costs associated with esophageal protection devices, these features offer compelling evidence for use of esophageal protection as routine care for AF ablation”.

Marlon Munera

and 6 more

Background: The shrimp Litopaneus vanammei is an important source of food allergens but its allergenic repertoire is poorly characterized. Cross reactivity between crustacean and mites has been characterized, with tropomyosin, the most relevant allergen involved. The aim of this study was the structural and immunological characterization of an allergen belonging to the Fatty Acid Binding Protein (FABP) family from L. vannamei (LvFABP). Methods: ELISA, skin prick test (SPT) and basophil activation assays were performed to determine IgE reactivity and allergenicity of LvFABP. LC-MS/MS and Circular Dichroism experiments were done for structural analysis. B-cell epitope mapping with overlapping peptides, and cross-inhibition studies using human sera were done to identify antigenic regions and cross-reactivity. Results: The recombinant LvFABP showed IgE reactivity in 27% of allergic patients tested and showed allergenic activity when tested for basophil activation and SPT in shrimp sensitized patients. CD-spectroscopy of LvFABP revealed that the protein is folded with a secondary structure composed of mainly β-strands and a smaller fraction of  helices. This is consistent with molecular modelling results, which exhibit a typical β barrel fold with two α-helices and ten β-strands. Epitope mapping identified two IgE binding antigenic regions and inhibition assays found high cross reactivity between LvFABP and Blo t 13, mediated by the antigenic region involving amino acids 53 to 73. Conclusions: Our results support LvFABP as an allergen with cross reactivity with the allergen Blo t 13. This new allergen could help to understand new mechanisms of sensitization to seafood such as shrimp.

Antonino Romano

and 10 more

Background: Nonimmediate (delayed) allergic reactions to penicillins are common and some of them can be life-threatening. The genetic factors influencing these reactions are unknown/poorly known/poorly understood. We assessed the genetic predictors of a delayed penicillin allergy that cover the HLA loci. Methods: Using next-generation sequencing (NGS), we genotyped the MHC region in 24 patients with delayed hypersensitivity compared with 20 patients with documented immediate hypersensitivity to penicillins recruited in Italy. Subsequently, we analyzed in silico Illumina Immunochip genotyping data that covered the HLA loci in 98 Spanish patients with delayed hypersensitivity and 315 with immediate hypersensitivity compared to 1,308 controls. Results: The two alleles DRB3*02:02:01:02 and DRB3*02:02:01:01 were reported in twenty cases with delayed reactions (83%) and ten cases with immediate reactions (50%), but not in the Allele Frequency Net Database. Bearing at least one of the two alleles increased the risk of delayed reactions compared to immediate reactions, with an OR of 8.88 (95% CI, 3.37–23.32; P <0.0001). The haplotype (ACAA) from rs9268835, rs6923504, rs6903608, and rs9268838 genetic variants of the HLA-DRB3 genomic region was significantly associated with an increased risk of delayed hypersensitivity to penicillins (OR, 1.7; 95% CI: 1.06–1.92; P=0.001), but not immediate hypersensitivity. Conclusion: We showed that the HLA-DRB3 locus is strongly associated with an increased risk of delayed penicillin hypersensitivity, at least in Southwestern Europe. The determination of HLA-DRB3*02:02 alleles in the risk management of severe delayed hypersensitivity to penicillins should be evaluated further in larger population samples of different origins.

Fanny Delehaye

and 29 more

Objective Ovarian mature teratoma (OMT) is a common ovarian tumor found in the pediatric population. In 10% to 20% of cases, OMT occurs as multiple synchronous or metachronous lesions on ipsi- or contralateral ovaries. Ovarian sparing surgery (OSS) is recommended to preserve fertility, but total oophorectomy (TO) is still performed. This study reviews the clinical data of patients with OMT, and analyzes risk factors for second events. Design A retrospective review of all girls under 18 years of age with OMTs was performed. Data on clinical features, imaging, laboratory studies, surgical reports, follow-up second events and their management were retrieved. Results Overall, 350 children were identified. Eighteen patients (5%) presented with a synchronous bilateral form at diagnosis. Surgery was performed by laparotomy (85%) and laparoscopy (15%). OSS and TO were performed in 59% and 41% of cases respectively. Perioperative tumor rupture occurred in 23 cases, independently of the surgical approach. Twenty-nine second events occurred (8.3%) in a median time of 30.5 months from diagnosis (ipsilateral: 8 cases including one malignant tumor, contralateral: 18 cases, both ovaries: 3 cases). A large palpable mass, bilateral forms at diagnosis and perioperative rupture had a statistical impact on the risk of second event, whereas type of surgery or approach did not. Conclusion This study is a plea in favor of OSS as the first choice of treatment of OMT when possible. Close follow-up during the first five years is mandatory considering the risk of 8.3% of second events especially in cases with risk factors.

Remzi BESTAS

and 1 more

Background and aims : Colorectal cancers are one of the most common types of cancer. Gastric intestinal metaplasia is considered a precancerous lesion that can progress into gastric cancer. Even though there are previous publications stating that Helicobacter pylori and intestinal metaplasia are related to colorectal adenomas, there are also studies stating the opposite. This study aims to determine the relationship between gastric intestinal metaplasia and colorectal neoplasia. Methods: A total of 214 patients between the ages of 19 and 92 who underwent combined gastroscopy and colonoscopy between August 2016 and April 2020 were included in this retrospective study. Medical records including demographic data, gastroscopy and colonoscopy findings and histopathology results of the patients were reviewed and analyzed. The association of intestinal metaplasia and Helicobacter pylori infection with colorectal neoplasia was evaluated in these patients. Results: The mean age of the patients included in the study was 49.07±15.80, and 125 (58.4%) of the patients were male. A statistically significant correlation was found between intestinal metaplasia and colon neoplasm prevalence (p= 0.03). However, such a correlation was not seen between Helicobacter pylori and colon neoplasia. Conclusion: A positive correlation was found between gastric intestinal metaplasia, which is a precancerous lesion, and colon neoplasia. Even though this correlation indicates higher prevalence rates of colon neoplasia in patients with gastric intestinal metaplasia, how to evaluate these patients in terms of colon neoplasia remains a controversial issue.

Siri Hauge

and 3 more

Objective: To determine if children born preterm were at increased risk of influenza hospitalization up to age five. Methods: National registry data on all children born in Norway between 2008 and 2011 was used in Cox regression models to estimate adjusted hazard ratios (aHR) for influenza hospitalizations up to age five in children born preterm (<37 pregnancy weeks). HRs were also estimated separately for very preterm (<32 weeks), early term (37-38 weeks), and post-term (≥42 weeks) children. Results: Among 238 628 children born in Norway from January 2008 to December 2011, 15 086 (6.3%) were born preterm. There were 754 (0.3%) children hospitalized with influenza before age five. The rate of hospitalizations in children born preterm was 1.4 per 10 000 person-years (95% confidence interval [CI]: 1.1-1.7), and 0.6 per 10 000 person-years (95% CI: 0.5-0.6) in children born at term (≥37 weeks). Children born preterm had a higher risk of influenza hospitalization before age 5: aHR 2.33 (95% CI: 1.85-2.93). The risk increased with decreasing gestational age and was highest among those born very preterm; aHR 4.07 (95% CI: 2.63-6.31). Compared to children born at 40-41 weeks, children born early term also had an elevated risk of influenza hospitalization; aHR (37 weeks) 1.89 (95% CI: 1.43-2.40), aHR (38 weeks) 1.43 (95% CI: 1.15-1.78). Conclusion: Children born preterm had a higher risk of influenza hospitalizations before age five. An elevated risk was also present among children born at an early term. Children born preterm would benefit from influenza vaccinations.

Cheryl Lohr

and 4 more

In 2010, vulnerable golden bandicoots (Isoodon auratus) were translocated from Barrow Island, Western Australia, to a predator-free enclosure on the Matuwa Indigenous Protected Area. Golden bandicoots were once widespread throughout a variety of arid and semi-arid habitats of central and northern Australia. Like many small to medium-sized marsupials, the species has severely declined since colonisation and has been reduced to only four remnant natural populations. Between 2010 and 2020 the reintroduced population of golden bandicoots on Matuwa was monitored via capture-mark-recapture data collection which was used in spatially explicit capture-recapture analysis to monitor their abundance over time. In 2014, we used VHF transmitters to examine the home range and habitat selection of 20 golden bandicoots in the enclosure over a six-week period. We used compositional analysis to compare the use of four habitat types. Golden bandicoot abundance in the enclosure slowly increased between 2010 and 2014 and has since plateaued at approximately one quarter of the density observed in the founding population on Barrow Island. The population may have plateaued because some bandicoots escape through the fence. Golden bandicoots used habitats dominated by scattered shrubland over spinifex grass more than expected given the habitat’s availability. Nocturnal foraging range was influenced by sex and trapping location, whereas diurnal refuge habitat was consistent across sex and trapping location. Our work suggests that diurnal refuge habitat may be an important factor for the success of proposed translocations of golden bandicoots.

Xibin Ji

and 5 more

A knowledge of the exchanges of energy and water over the terrestrial surface is the first step to understand the ecohydrological mechanisms, particularly in water-limited ecosystems in the dryland environments. However, patterns of energy exchange and evapotranspiration (ET) are not well understood in the oasis-desert ecotone, which plays an important role in protecting oasis against the threat of desertification in northwestern China’s arid regions. Here the continuous measurements of surface energy fluxes were made using eddy covariance in conjunction with auxiliary measurements for two years (2014-2015) at a shrubland within an oasis-desert ecotone in the arid regions, northwestern China. Statistical analysis on 30-min time scale indicates that about 50% of daytime net radiation (Rn) over the shrubland is dissipated as H on average, which peaks in spring; one third Rn is consumed by soil heat flux (G). Only 9% of Rn was consumed for latent heat flux (λE), which peaks in summer (21% in 2014 and 16% in 2015), corresponding to the season with highest rainfall among all seasons. Daily mean ET is about 1 mm·d−1 during growing season of the shrub species. The rapid and transient increase in ET occurs following a rainfall event. A switch in surface soil moisture from 0.04 to 0.11 m3·m−3 causes an increase in Rn by about 11% and λE by 151% at the shrubland, respectively. Accumulated annual ET were 195 and 181 mm in 2014 and 2015, respectively, exceeding the corresponding P by about 87 and 77 mm, indicating that groundwater may be another important source of water for ET over the shrubland aside from P. These results provide valuable insight into the mechanisms of sustaining energy and water balance at the ecotone, and then produce some management guidelines for allocating water resources and protecting vegetation.

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Huseyin Kazan

and 6 more

Objective: To investigate the factors, especially preoperative urinalysis, predicting postoperative early infection after retrograde intrarenal surgery (RIRS) in 1-2 cm renal stones. Methods: Of the 642 patients who underwent RIRS between September 2013 and July 2019, 289 patients with a total stone size of 1-2 cm were included in the study. Patients were divided into two groups as with and without postoperative urinary tract infection. The demographic data and perioperative findings of all patients were retrospectively reviewed. Sterile urine cultures were obtained in all patients during the preoperative 30-day period and urine analysis values were included in the data. Results: Urinary system infection (UTI) was seen in 20 (6.9%) of 289 patients. Patient demographics were similar between groups. There was no statistically significant difference between the two groups in terms of stone diameter and stone localization (median diameter 13.5 vs 15, p=0.285). Patients with postoperative UTI had a higher rate of UTI history (55% vs 20.5%, p=0.000) and longer operative times (62.5 vs 60 min., p=0.008). Rate of pyuria, leukocyte esterase and nitrite positivity were observed more frequently in patients with postoperative UTI. In multivariate analysis, UTI history, prolonged operative time, and nitrite positivity were found to be independent risk factors for postoperative UTI. Conclusion: Nitrite positivity in preoperative urinanalysis, history of UTI and prolonged operation time are the factors that predict the postoperative infection in RIRS for stones between 1-2 cm.

Gunter Sturm

and 38 more

Background: There is controversy whether taking β-blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT). Methods: In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking β-blockers or ACEI show more systemic AE during VIT compared to patients without such treatment. Results: In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took β-blockers, 11.9% ACEI, 5.0% β-blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43–1.22, p=0.25). The severity of the initial sting reaction was not affected by the intake of β-blockers or ACEI (OR: 1.14, 95% CI: 0.89–1.46, p=0.29). In total, 210 (17.7%) patients were re-stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took β-blockers, none an ACEI. Conclusions: This trial provides robust evidence that taking β-blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; Clinicaltrials.gov number, NCT04269629)

Nazanin Kermani

and 12 more

Background. Patients with severe asthma may have a greater risk of dying from COVID-19 disease. Angiotensin converting enzyme-2 (ACE2) and the enzyme proteases, transmembrane protease serine 2 (TMPRSS2) and FURIN, are needed for viral attachment and invasion into host cells. Methods. We examined microarray mRNA expression of ACE2, TMPRSS2 and FURIN in sputum, bronchial brushing and bronchial biopsies of the European U-BIOPRED cohort. Clinical parameters and molecular phenotypes, including asthma severity, sputum inflammatory cells, lung functions, oral corticosteroid (OCS) use, and transcriptomic-associated clusters, were examined in relation to gene expression levels. Results. ACE2 levels were significantly increased in sputum of severe asthma compared to mild-moderate asthma. In multivariate analyses, sputum ACE2 levels were positively associated with OCS use and male gender. Sputum FURIN levels were significantly related to neutrophils (%) and the presence of severe asthma. In bronchial brushing samples, TMPRSS2 levels were positively associated with male gender and body mass index, whereas FURIN levels with male gender and blood neutrophils. In bronchial biopsies, TMPRSS2 levels were positively related to blood neutrophils. The neutrophilic molecular phenotype characterised by high inflammasome activation expressed significantly higher FURIN levels in sputum than the eosinophilic Type 2-high or the pauci-granulocytic oxidative phosphorylation phenotypes. Conclusion. Levels of ACE2 and FURIN may differ by clinical or molecular phenotypes of asthma. Sputum FURIN expression levels were strongly associated with neutrophilic inflammation and with inflammasome activation. This might indicate the potential for a greater morbidity and mortality outcome from SARS-CoV-2 infection in neutrophilic severe asthma.

Mehmet Pehlivaoğlu

and 5 more

Aim: This study evaluated the effect of intracavitary levobupivacaine infusion diluted with locally applied isotonic solution for pain control in cystoscopy. Methods: Included in this study are 100 patients who had previously undergone transurethral tumor resection for bladder tumor and were followed up by cystoscopy. The patients were randomized into five groups (n = 20). In the first, second, third, and fourth groups, 4, 6, 8, and 10 mL of levobupivacaine HCl (5.0 mg/mL) were mixed with 26, 24, 22, and 20 mL of isotonic solution, respectively. Hence, the total mixture was 30 mL for each group. The fifth group was the control group. In this group, the standard method commonly used in most clinics was utilized. That is, a gel containing Cathejell-2% lidocaine (25 mg lidocaine) was applied. Cystoscopic interventions were performed with a 17.5 Fr rigid cystoscope and 0°, 30°, and 70° lens. During cystoscopy and 30 min later, the pain status of patients was assessed using the Visual Analogue Scale (VAS), and patient satisfaction was questioned. Results: The mean VAS score during and after the cystoscopy procedure was significantly lower in the levobupivacaine groups compared to the lidocaine group. In addition, patient satisfaction in the levobupivacaine groups was significantly higher than in the lidocaine group. No drug-related side-effects were observed in all groups. Conclusion: Thus, levobupivacaine is a more effective drug than lidocaine alone to control pain during cystoscopy. The use of levobupivacaine is recommended to prevent possible complications of general anesthesia by eliminating the need for the aforementioned as well as its cost-saving advantage.

Yanhui Dong

and 4 more

Groundwater age is often used to estimate groundwater recharge through a simplified analytical approach. This estimated recharge is thought to be representative of the mean recharge between the point of entry and the sampling point. However, given the complexity in actual recharge, whether the mean recharge is reasonable is still unclear. This study examined the validity of the method to estimate long-term average groundwater recharge and the possibility of obtaining reasonable spatial recharge pattern. We first validated our model in producing reasonable age distributions using a constant flux boundary condition. We then generated different flow fields and age patterns by using various spatially-varying flux boundary conditions with different magnitudes and wavelengths. Groundwater recharge was estimated and analyzed afterwards using the method at the spatial scale. We illustrated the main findings with a field example in the end. Our results suggest that we can estimate long-term average groundwater recharge with 10% error in many parts of an aquifer. The size of these areas decreases with the increase in both the amplitude and the wavelength. The chance of obtaining a reasonable groundwater recharge is higher if an age sample is collected from the middle of an aquifer and at downstream areas. Our study also indicates that the method can also be used to estimate local groundwater recharge if age samples are collected close to the water table. However, care must be taken to determine groundwater age regardless of conditions.

Xinyi Guan

and 4 more

Adriana Bustamante

and 3 more

Yasser Mubarak

and 1 more

Background: Small Aortic Annulus (AA) is big issue during Aortic Valve Replacement (AVR) necessitating replacement of an undersized prosthetic valve especially with Double Valve Replacement (DVR). Despite that small aortic valve prostheses can lead to Prosthesis-Patient Mismatch (PPM), there remains reluctance to perform aortic root enlargement (ARE) procedures fearing from morbidity and mortality. Objective: To evaluate clinical and echocardiographic outcomes in patients with small aortic annulus undergoing double valve replacement. Methods: The study included 100 consecutive patients underwent DVR for combined rheumatic aortic and mitral valve diseases, between Jan. 2016 and Sept. 2020. Only (50) patients had ARE with DVR. ARE was performed using an autologous or bovine pericardium or Dacron patch by Nicks or Manouguian procedures. The estimated postoperative end-points were mortality, effective orifice areas (EOA), mean aortic pressure gradient and valve-related complications. The least postoperative follow-up period was 6 months. Results: The study included 30 male and 70 female patients with mean age of 35±20 years, body surface area (BSA) of 1.7 ±0.3 m2, aortic annulus diameter was 20±1.4 mm, aortic orifice area was 0.8±0.1 cm2, and mean pressure gradient 85±2.5 mmHg. During follow-up period, there was a mild to moderate paravalvular leak (1%) with, (1%) heart block, and residual gradient on prosthetic aortic valve; that was all in DVR alone. Conclusion: Enlargement of aortic root by Nicks or Manouguian technique is safe and effective in patients with small aortic annulus undergoing double valve replacements.

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