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Lei Su

and 6 more

Previous studies have demonstrated changes in plant growth and reproduction in response to nutrient availability, but how investigations of such responses to multiple levels of nutrient enrichment remains unclear. In this study, we manipulated nitrogen (N) and phosphorus (P) availability to examine seed production responses to three levels each of N and P addition in a factorial experiment: no N addition (0 g N m-2 yr-1), low N addition (10 g N m-2 yr-1), high N addition (40 g N m-2 yr-1), and no P addition (0 g P m-2 yr-1), low P addition (5 g P m-2 yr-1), high P addition (10 g P m-2 yr-1). Low N addition enhanced seed production by 814%, 1371%, and 1321% under ambient, low, and high P addition levels, respectively. High N addition increased seed production by 2136%, 3560%, and 3550% under ambient, low, and high P addition levels, respectively. However, P addition did not affect seed production in the absence of N addition, but it did enhance it under N addition. Furthermore, N addition enhanced seed production mainly by increasing the tiller number and inflorescence abundance per plant, whereas P addition stimulated it by decreasing the plant density yet stimulating height of plants and their seed number per inflorescence. Our results indicate seed production is limited not by P but rather by N in the temperate steppe, whereas seed production will be increased by P addition when N availability is improved. These findings enable a better understanding of plant reproduction dynamics of steppe ecosystems under intensified nutrient enrichment and can inform their improved management in the future.

Sinead Ahearn Ford

and 17 more

Long Term Disruption of Cytokine Signalling Networks are Evident Following SARS-CoV-2 InfectionSinead Ahearn-Ford1, Nonhlanhla Lunjani1, Brian McSharry1,2, John MacSharry1,2,3, Liam Fanning1,3, Gerard Murphy4, Cormac Everard4, Aoife Barry4, Aimee McGreal4, Sultan Mohamed al Lawati4, Susan Lapthorne4, Colin Sherlock4, Anna McKeogh4, Arthur Jackson4, Eamonn Faller4, Mary Horgan3,4, Corinna Sadlier4, Liam O’Mahony1,2,3*1APC Microbiome Ireland, University College Cork, Cork, Ireland2School of Microbiology, University College Cork, Cork, Ireland3Department of Medicine, University College Cork, Cork, Ireland4 Department of Infectious Diseases, Cork University Hospital, Cork, Ireland*Corresponding author – liam.omahony@ucc.ieTo the Editor,The current pandemic caused by the SARS-CoV-2 virus has so far infected more than 130 million people worldwide, resulting in approximately 3 million deaths. While the current clinical and public health priorities are designed to limit severe acute and fatal episodes of the disease, and to quickly roll out vaccines to the general population, it has become apparent that there may also be significant detrimental long-term effects following SARS-CoV-2 infection that impact daily functioning and quality of life1. The mechanisms underpinning the post-acute sequelae of SARS-CoV-2 infection’s long-lasting symptoms can include direct effects of the infection (e.g. endothelial damage, lung fibrosis) or indirect effects associated with changes in the microbiome or abnormalities in inflammatory and immune signalling pathways stimulated by the infection2,3.In order to examine the potential long-term immune changes that occur following elimination of the primary infection, we examined the levels of 52 cytokines and growth factors (using MSD multiplex kits) in the serum of patients that attended follow-up post-COVID infection clinics at Cork University Hospital, Cork, Ireland (The Clinical Research Ethics Committee of the Cork Teaching Hospitals approved this study and all patients provided informed consent). All patients had been hospitalised for PCR-proven SARS-CoV-2 infection (median in-patient stay of 5.5 days, range 1 day to 24 days) during the first wave of the pandemic in Ireland (March-May 2020). 38 serum samples were obtained from 24 patients (median age 53.5 years, 11 female) at 3-9 months following hospital discharge. Clinical severity ranged from mild to critical during hospitalisation and the most common symptoms at follow-up clinics were fatigue and/or dyspnoea (supplementary Table S1). Sera obtained prior to the pandemic from 29 healthy volunteers (median age 43.2 years, 14 female) were analysed in parallel.Of the 52 analytes measured, 19 were significantly elevated in post-COVID patient sera compared to healthy controls (supplementary Table S2). These 19 mediators are illustrated as dot plots in Figure 1 and Figure 2. One group of mediators, c-reactive protein (CRP), serum amyloid A (SAA), Interleukin-1 receptor antagonist (IL-1RA), IL-6, IL-8, IL-15, IL-16, monocyte chemotactic protein (MCP)-1 and MCP-4, can be broadly categorised as being associated with ongoing inflammatory responses (Figure 1a)4. These mediators remained as elevated in samples taken 6-9 months following hospital discharge as those levels observed 3-6 months following discharge (p<0.05 versus controls, ANOVA). A second group of mediators, vascular endothelial growth factor (VEGF-A), soluble tyrosine-protein kinase receptor Tie-2 (Tie-2), soluble intercellular adhesion molecule (ICAM-1) and basic fibroblast growth factor (bFGF), can be generally associated with endothelial dysfunction, remodelling and angiogenesis (Figure 1b)5. The remaining elevated mediators are associated with patterns of lymphocyte polarisation. Elevated IL-4, macrophage-derived chemokine (MDC) and thymic stromal lymphopoietin (TSLP) sera levels indicate activation of TH2 responses (Figure 2a), while IL-17A, macrophage inflammatory protein (MIP)-3α and IL-12/23p40 indicate ongoing TH17 activity (Figure 2b). Other indicators of TH2-associated activities are just outside statistical significance (IL-5, p=0.06; supplementary Table S2). While TH1 responses are well described to be upregulated during acute infection6, the levels of these mediators (e.g. IFN-γ, IP-10) decrease following elimination of the virus and are at control levels in our cohort of post-COVID patients (supplementary Table S2).Our data suggests that there are long term immunological consequences following SARS-CoV-2 infection, at least in those that had acute symptoms severe enough to require hospitalisation. While the relatively low number of patients included in our study at this stage does not allow us to perform subgroup analysis, it is possible that these immune mediators may associate with clinically meaningful disease variables and ultimately may be of therapeutic value, if findings are replicated in future studies. Of particular interest is the elevation in TH2-associated mediators. Could this response be a component of the mucosal repair mechanisms that occur following viral damage, or does this indicate new TH2-associated pathological immune activity that might underpin an increased risk of developing allergy or asthma? Clearly the potential immune mechanisms underpinning the emerging post-COVID clinical entities will become increasingly more important to understand as the health care systems adapt to caring for large numbers of COVID-19 survivors during the coming months and years.

Dima Ezmigna

and 3 more

The Asthma Predictive Index (API) predicts later asthma in preschoolers with frequent wheeze. We hypothesized that airway cytology differs between API positive(+ve)/negative(-ve) children with uncontrolled/recurrent wheezing with dominance of eosinophils in API (+ve) and neutrophils in API (-ve) groups respectively. Objective: To compare bronchoalveolar lavage (BAL) cell profiles in API (+ve)/(-ve) children with recurrent wheezing unresponsive to inhaled corticosteroids (ICS). Design: A retrospective analysis of BAL in 43 children, 3-36 months (median: 14 months) receiving ICS (31 API +ve ; 12 API -ve). BAL cell differential counts, bacterial/viral cultures, and lipid-laden macrophage percentages (LLM) were analyzed. Cell counts presented as median (range). Results: Neutrophil percentages were increased in both groups [API -ve 16% (1-76%); API +ve 42% (1-95%); P=NS]. Cell percentages were similar for lymphocytes [API-ve 12% (1-30%); API +ve 7% (1-37%)], and macrophages [API -ve 67.5% (12-97%); API +ve 41 % (2-94%)]. Eosinophil percentages were low in both groups [API -ve 1 % (1-2%); API +ve 1 % (1-11%)]. Bacterial cultures were positive in 16 (80%) API +ve and 4 (33%) API -ve patients (P=0.10). Conclusion: Cell profiles do not differ between API groups in children ≤36 months with recurrent wheezing unresponsive to ICS. Positive correlation between neutrophil percentages and positive bacterial cultures was seen independent of API. Persistent bacterial bronchitis likely plays an important role in the persistence of symptoms unresponsive to inhaled corticosteroid therapy regardless of API status with a trend to more positive cultures in API positive children.

Barnabas Atwiine

and 10 more

Introduction - Treatment abandonment contributes significantly to poor survival of children with cancer in low-middle-income countries (LMICs). In order to inform an approach to this problem at our Cancer Unit, we investigated why caregivers withdraw their children from treatment. Methods – In a qualitative study, in-depth interviews were conducted with caregivers of children who had abandoned cancer treatment at the Paediatric Cancer Unit (PCU) of Mbarara Regional Referral Hospital (MRRH) in South Western Uganda, between May 2017 and September 2020. Recorded in-depth interviews with caregivers were transcribed and analyzed to identify themes of caregiver self-reported reasons for treatment abandonment. Results - Seventy-seven out of 343 (22.4%) children treated for cancer at MRRH abandoned treatment during the study period; 20 contactable and consenting caregivers participated in the study. The median age of children’s caregivers was 37 years and most (65%) were mothers. At the time of this study, eight (40%) children were alive and 5 (62.5%) were males; with a median age of 6.5 years. Financial difficulties, other obligations, the child falsely appearing cured, preference for alternative treatments, belief that cancer was incurable, fear that the child’s death was imminent and chemotherapy side-effects were the caregivers’ reasons for treatment abandonment. Conclusions and Recommendation – Treatment abandonment among children with cancer in Uganda is, most times, as a result of difficult conditions beyond the caregivers’ control and needs to be approached with empathy and support.

Moslem Abdelghafar

and 3 more

Aim: Cardiac surgery patients have different resuscitative needs than other patients who experience in-hospital cardiac arrest, this was addressed in the guidelines. However, it is unknown how widely the guidelines are practiced, or a training protocol is followed in different cardiac surgery units in Egypt. Methods: A 21-question survey is created and included: Participants demographics, Prevalence of cardiac arrest, Cardiac arrest protocol, Emergency resternotomy technique, Training protocols. Survey was disseminated through social media messaging platforms during the period between November 2020 and January 2021. Results: 95 responses were from 11 centres across Egypt. 68.5% of the respondents were surgeons, 76.8% of participants were junior surgeons. For patients who go into VF after cardiac surgery, respondents would attempt a median of 3 shocks with only 24.2% commencing defibrillation shocks before external cardiac massage, while the majority initiating CPR immediately and performing emergency resternotomy in a median time of 10 mins. 56.8% would give 1 mg of adrenaline as soon the cardiac arrest was established. If a surgeon was not available, only 36.8% of respondents would allow any trained personnel to perform the emergency resternotomy. Only 9.5% practice regularly on emergency sternotomies. 75% think tailored training is important and staff should be oriented about it in the future. Conclusion: An action plan is required to improve the awareness of the junior surgeons with the Cardiac Advanced Life Support Protocol.


and 4 more

Aim: Urinary incontinence is an important problem that can arise due to neurogenic or functional reasons and can negatively affect the psychological, social and personality development of children. This study was conducted in Eskişehir province, on secondary school students in order to determine the prevalence and nature of urinary incontinence at night and/or daytime. Methods: The study universe included all secondary school students attending state elementary schools in the city center of Eskişehir (N=34.000). Ethics Committee and Provincial Directorate of National Education approval was obtained before conducting the study, which was supported by Eskişehir Osmangazi University Scientific Research Projects Commission (2017-1876) . A data collection form prepared by the researchers, and a consent form were delivered in sealed envelope to the parents via the students. The study data were collected between 09.05.2018-30.05.2018. Only volunteers were included in the study. 6957 questionnaires which have been fully completed from the 7370 surveys have been taken into consideration. The statistical analysis was carried out using the SPSS soft ware package. Results: The number of children found to have urinary incontinence was determined to be 215 (3.1%). It has been determined that 33 children (0.5%) have urinary incontinence only at daytime, 61 children (0.9%) have urinary incontinence both at night and daytime, and 121 children (1.7%) have urinary incontinence only at night. It was observed that 56% of the children suffering from urinary incontinence had not applied to any health institution for treatment before. Conclusions: Children and families with urinary incontinence need medical information and support to cover the cause of the problem and suggestions for solutions. Accompanying pathologies in cases to be detected can be determined in the early period by means of school screenings and medical evaluation and support can prevent the psychosocial and personality development of children from being adversely affected.

Bertrand Ebner

and 8 more

Introduction: Due to the inability to keep up with the demand for heart transplantation, there is an increased utilization of left ventricular assist devices (LVAD). However, paucity of data exists regarding the association of household income with in-hospital outcomes after LVAD implantation. Methods: Retrospective cohort study using the NIS to identify all patients ≥18 years who underwent LVAD implantation from 2011-2017. Statistical analysis was performed comparing low household income (≤50th percentile) and high income (>50th percentile). Results: A total of 25,503 patients underwent LVAD implantation. The low-income group represented 53% and the high-income group corresponded to 47% of the entire cohort. The low-income group was found to be younger (mean age 55 ±14 vs. 58 ±14 years), higher proportion of females (24% vs. 22%), and higher proportion of blacks (32% vs. 16%, p<0.001 for all). The low-income group was found to have higher prevalence of hypertension, chronic pulmonary disease, smoking, dyslipidemia, obesity and pulmonary hypertension (p<0.001 for all). However, the high-income cohort had higher rate of atrial tachyarrhythmias and end-stage renal disease (p<0.001). During hospitalization, patients in the high-income group had increased rates of ischemic stroke, acute kidney injury, acute coronary syndrome, bleeding and need of extracorporeal membrane oxygenation (p<0.001 for all). We found that the unadjusted mortality had an OR 1.30 (CI [1.21-1.41], p<0.001) and adjusted mortality of OR 1.14 (CI [1.05-1.23], p=0.002). Conclusion: In patients undergoing LVAD implantation nationwide, low-income was associated with increased comorbidity burden, younger age, and fewer in-hospital complications and all-cause mortality.

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.

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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; 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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