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This research aims to investigate biochemical activities of Phragmites australis, as a biomarker of heavy metals including Cr, Ni, V, Zn and Co. In order to determine and analyze biochemical parameters including flavonoids, Non-Protein Thiols (NPTs), chlorophyll a and b and total chlorophyll pigments in the roots, stems and leaves of P. australis, sediment and plant samples were collected from 7 stations in the Anzali wetland. Based on the obtained results, there were positive and significant correlation coefficients among the concentrations of the heavy metals in the sediments with non-protein thiols and flavonoids, also negative and significant correlation coefficients were found between the heavy metal contents and the total chlorophyll in the leaves in all the sampling stations. Therefore, it can be concluded that these parameters are appropriate biomarkers to evaluate the heavy metal pollution in the sediments of the aquatic ecosystem., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) infections impose a considerable burden on health systems, yet there is remarkable variation in the global incidence and epidemiology of MRSA. The MACOTRA consortium aimed to identify bacterial markers of epidemic success of MRSA isolates in Europe using a representative MRSA collection originating from France, the Netherlands and the United Kingdom., Methods: Operational definitions of success were defined in consortium meetings to compose a balanced strain collection of successful and sporadic MRSA isolates. Isolates were subjected to antimicrobial susceptibility testing and whole-genome sequencing; genes were identified and phylogenetic trees constructed. Markers of epidemiological success were identified using genome-based time-scaled haplotypic density analysis and linear regression. Antimicrobial usage data from ESAC-Net was compared with national MRSA incidence data., Results: Heterogeneity of MRSA isolate collections across countries hampered the use of a unified operational definition of success; therefore, country-specific approaches were used to establish the MACOTRA strain collection. Phenotypic antimicrobial resistance varied within related MRSA populations and across countries. In time-scaled haplotypic density analysis, fluoroquinolone, macrolide and mupirocin resistance were associated with MRSA success, whereas gentamicin, rifampicin and trimethoprim resistance were associated with sporadicity. Usage of antimicrobials across 29 European countries varied substantially, and β-lactam, fluoroquinolone, macrolide and aminoglycoside use correlated with MRSA incidence., Discussion: Our results are the strongest yet to associate MRSA antibiotic resistance profiles and antibiotic usage with the incidence of infection and successful clonal spread, which varied by country. Harmonized isolate collection, typing, resistance profiling and alignment with antimicrobial usage over time will aid comparisons and further support country-specific interventions to reduce MRSA burden., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Kidney transplantation reduces mortality in patients with end stage renal disease (ESRD). Decisions about performing kidney transplantation in the setting of a prior cancer are challenging, as cancer recurrence in the setting of immunosuppression can result in poor outcomes. For cancer of the breast, rapid advances in molecular characterization have allowed improved prognostication, which is not reflected in current guidelines. We developed a 19-question survey to determine transplant surgeons' knowledge, practice, and attitudes regarding guidelines for kidney transplantation in women with breast cancer. Of the 129 respondents from 32 states and 14 countries, 74.8% felt that current guidelines are inadequate. Surgeons outside the United States (US) were more likely to consider transplantation in a breast cancer patient without a waiting period (p = .017). Within the US, 29.2% of surgeons in the Western region would consider transplantation without a waiting period, versus 3.6% of surgeons in the East (p = .004). Encouragingly, 90.4% of providers surveyed would consider eliminating wait-times for women with a low risk of cancer recurrence based on the accurate prediction of molecular assays. These findings support the need for new guidelines incorporating individualized recurrence risk to improve care of ESRD patients with breast cancer., (© 2021 The American Society of Transplantation and the American Society of Transplant Surgeons.)

In the present study, preparation of blend hydrogels of tyramine conjugated gum tragacanth and poly (vinyl alcohol) was carried out by electron beam irradiation, and modification of hydrogel properties with poly (vinyl alcohol) was demonstrated. Gel content, swelling behavior, pore size and mechanical and rheological properties of hydrogels prepared at 14, 28 and 56 kilogray (kGy) with different ratios of polymers were investigated. Gel content increased from 67 ± 2% for pure tyramine conjugated gum tragacanth hydrogel to >92% for blend hydrogels. However, the corresponding equilibrium swelling degree decreased from 35.21 ± 1.51 to 9.14 ± 1.66 due to the higher crosslink density of blend hydrogel. The mechanical strength of the hydrogels with interconnected pores increased significantly in the presence of poly (vinyl alcohol) and increasing irradiation dose up to 28 kGy with a twenty-fold enhancement of stress fracture and excellent elastic recovery in cyclic compression analysis. The equilibrium swelling degree of blend hydrogel containing 3% w/v tyramine conjugated gum tragacanth and 2% w/v poly (vinyl alcohol) prepared at 28 kGy was 16.59 ± 0.81. The biocompatibility of hydrogels was tested in the presence of rabbit bone marrow mesenchymal stem cells. The viability of cells exposed to hydrogel extract was >92% after 7 days of culture and indicated hydrogel biocompatibility with potential biomedical applications., Competing Interests: Declaration of competing interest The authors have no affiliation with any organization with a direct or indirect financial interest in the subject matter discussed in the manuscript., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Electron beam irradiation was used for the synthesize of porous and non-porous pectin based hydrogels through conjugation of pectin with 5-hydroxytryptophan in the presence and absence of sodium dodecyl sulfate, respectively. The hydrogels were characterized by different methods. Tetracycline hydrochloride was loaded on the hydrogels by swelling equilibrium method and its release in different media was studied. The effect of SDS amount and electron beam irradiation dose on the swelling, drug loading, drug release, gel content, and mechanical properties were investigated. The release of drug form both hydrogels followed non-Fickian diffusion mechanism and was best fitted with the Korsmeyer-Peppas model. In vitro, drug release studies revealed that the release of drug from non-porous hydrogel is relatively slow while its release from porous hydrogel occurs with higher amounts and faster rate. Biocompatibility and cytotoxic analysis indicate that the prepared hydrogels dressing are non-thrombogenic, non-hemolytic and non-toxic. Furthermore, acceptable bacteria growth inhibition against Escherichia coli and Staphylococcus aureus were observed for both drug-loaded hydrogels. Thus, these hydrogels are suitable for the application of an antibacterial wound dressing., (Copyright © 2019. Published by Elsevier B.V.)

Common variable immunodeficiency (CVID) is a heterogeneous group of primary antibody deficiencies (PAD) which is defined by recurrent infections, hypogammaglobulinemia and defects in B-cell differentiation into plasma cells and memory B cells. T cell abnormalities have also been described in CVID patients. Several studies reported that Treg frequencies and their functional characteristics are disturbed and might account for the aberrant immune responses observed in CVID patients. The aim of this review is to describe phenotypic and functional characteristics of Treg cells, and to review the literature with respect to the reported Treg defects and its association with the clinical manifestation in CVID., (Copyright © 2016. Published by Elsevier Inc.)

Kidney transplantation is the optimal treatment for children with end-stage renal disease. For children with undocumented immigration status, access to kidney transplantation is limited, and data on transplant outcomes in this population are scarce. The goal of the present retrospective single-center study was to compare outcomes after kidney transplantation in undocumented children with those of US citizen children. Undocumented residency status was identified in 48 (17%) of 289 children who received a kidney transplant between 1998 and 2010. In undocumented recipients, graft survival at 1 and 5 years posttransplantation was similar, and mean estimated glomerular filtration rate at 1 year was higher than that in recipients who were citizens. The risk of allograft failure was lower in undocumented recipients relative to that in citizens at 5 years posttransplantation, after adjustment for patient age, donor age, donor type, and HLA mismatch (p < 0.04). In contrast, nearly one in five undocumented recipients who reached 21 years of age lost their graft, primarily because they were unable to pay for immunosuppressive medications once their state-funded insurance had ended. These findings support the ongoing need for immigration policies for the undocumented that facilitate access to work-permits and employment-related insurance for this disadvantaged group., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Few current studies compare the outcomes of islet transplantation alone (ITA) and pancreas transplantation alone (PTA) for type 1 diabetes (T1D). We examined these two beta cell replacement therapies in nonuremic patients with T1D with respect to safety, graft function and cost. Sequential patients received PTA (n = 15) or ITA (n = 10) at our institution. Assessments of graft function included duration of insulin independence; glycemic control, as measured by hemoglobin A1c; and elimination of severe hypoglycemia. Cost analysis included all normalized costs associated with transplantation and inpatient management. ITA patients received one (n = 6) or two (n = 4) islet transplants. Mean duration of insulin independence in this group was 35 mo; 90% were independent at 1 year, and 70% were independent at 3 years. Mean duration of insulin independence in PTA was 55 mo; 93% were insulin independent at 1 year, and 64% were independent at 3 years. Glycemic control was comparable in all patients with functioning grafts, as were overall costs ($138 872 for ITA, $134 748 for PTA). We conclude that with advances in islet isolation and posttransplant management, ITA can produce outcomes similar to PTA and represents a clinically viable option to achieve long-term insulin independence in selected patients with T1D., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)

For solid organ transplant (SOT) donors, nucleic acid-amplification testing (NAT) may reduce human immunodeficiency virus (HIV) and hepatitis C virus (HCV) transmission over antibody (Ab) testing given its shorter detection window period. We compared SOT donor NAT + Ab versus Ab alone using decision models to estimate incremental cost-effectiveness ratios (ICERs; cost per quality-adjusted life year [QALY] gained) from the societal perspective across a range of HIV/HCV prevalence values and NAT costs. The cost per QALY gained was calculated for two scenarios: (1) favorable: low cost ($150/donor)/high prevalence (HIV: 1.5%; HCV: 18.2%) and (2) unfavorable: high cost ($500/donor)/low prevalence (HIV: 0.1%; HCV: 1.5%). In the favorable scenario, adding NAT screening cost $161 013 per QALY gained for HIV was less costly) for HCV, and cost $86 653 per QALY gained for HIV/HCV combined. For the unfavorable scenario, the costs were $15 568 484, $221 006 and $10 077 599 per QALY gained, respectively. Universal HCV NAT + Ab for donors appears cost-effective to reduce infection transmission from SOT donors, while HIV NAT + Ab is not, except where HIV NAT is ≤$150/donor and prevalence is ≥1.5%. Our analyses provide important data to facilitate the decision to implement HIV and HCV NAT for deceased SOT donors and shape national policy regarding how to reduce infection transmission in SOT., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Morbid obesity is a relative contraindication for organ transplant because it is associated with higher postoperative morbidity and mortality. The safety and efficacy of laparoscopic sleeve gastrectomy (LSG) as a weight loss method for patients awaiting transplant has not been examined., Methods: A retrospective review was performed on morbidly obese patients awaiting liver or kidney transplant who underwent LSG from 2006 to 2012. Data included patient demographic characteristics, operative details, 30-day complications, percentage of excess weight loss, postoperative laboratory data, and status of transplant candidacy., Results: Twenty-six pretransplant patients underwent LSG. The mean age was 57 years, and 17 (65%) were women. Six patients had end-stage renal disease, and 20 patients had end-stage liver disease. The preoperative mean body mass index was 48.3 kg/m(2) (range 38-60.4 kg/m(2)). There were no deaths, and there were 6 postoperative complications: 2 superficial wound infections, 1 staple line leak, 1 postoperative bleed requiring blood transfusion, 1 transient encephalopathy, and 1 temporary renal insufficiency. The mean percentage of excess weight loss at 1, 3, and 12 months was 17% (n = 24/26), 26% (n = 23/26), and 50% (n = 18/20), respectively. All patients met our institution's body mass index cutoffs for transplantation by 12 months after the procedure. One patient's renal function stabilized, and he was taken off the transplant list. Eight patients eventually underwent solid organ transplant. Six received liver transplants, 1 patient received a combined liver and kidney transplant, and 1 received a kidney transplant. The mean time between LSG and transplant was 16.6 months., Conclusions: This is the largest case series involving LSG in patients awaiting solid organ transplantation. LSG is well tolerated, is technically feasible, and improves candidacy for transplantation., (Copyright © 2013 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Current guidelines define cardiac troponin I (TnI) as an indicator of necrosis when the concentration exceeds the 99% upper limit of a healthy reference population, a reference value near the assay's lowest detectable level. We assessed the utility of a modified TnI cutoff point derived from a population at low risk for coronary artery disease (CAD) and evaluated its utility in determining acute myocardial infarction (MI)., Methods: A modified TnI cutoff point was derived by the receiver operating characteristic (ROC) curve from 737 consecutive patients who underwent serial TnI measurements for exclusion of MI. Creatinine kinase isoenzyme MB (CK-MB) evolutionary change was used to define MI. The new derived cutoff point was validated using another subset of 320 patients who were evaluated for MI., Results: ROC-derived TnI cutoff point (A) was 0.65 μg/L, and its performance was compared to the recommended cutoff point ([B] 0.15 μg/L). Cutoff point A had greater specificity (94.5% vs. 86.9%, p < 0.001) but slightly lower sensitivity (96.5% vs. 100%, p < 0.01). Cutoff point A provided significantly greater positive predictive value (PPV) for MI (74.1% vs. 55.5%, p < 0.0001) and fewer false-positive errors, while preserving comparable negative predictive value (NPV) (98.9% vs. 100%)., Conclusion: A higher cutoff point derived from a reference population of patients at low risk for CAD may improve the TnI performance assay. The PPV for diagnosis of MI was significantly higher and false-positive values were fewer without affecting the NPV. The more reliable diagnosis of MI may have resulted, which, in turn, may have significant clinical and economic implications., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The applicability of islet transplantation as treatment for type 1 diabetes is limited by renal and islet toxicities of currently available immunosuppressants. We describe a novel immunosuppressive regimen using the antileukocyte functional antigen-1 antibody efalizumab which permits long-term islet allograft survival while reducing the need for corticosteroids and calcineurin inhibitors (CNI). Eight patients with type 1 diabetes and hypoglycemic unawareness received intraportal allogeneic islet transplants. Immunosuppression consisted of antithymocyte globulin induction followed by maintenance with efalizumab and sirolimus or mycophenolate. When efalizumab was withdrawn from the market in mid 2009, all patients were transitioned to regimens consisting of mycophenolate and sirolimus or mycophenolate and tacrolimus. All patients achieved insulin independence and four out of eight patients became independent after single-islet transplants. Insulin independent patients had no further hypoglycemic events, hemoglobin A1c levels decreased and renal function remained stable. Efalizumab was well tolerated and no serious adverse events were encountered. Although long-term follow-up is limited by discontinuation of efalizumab and transition to conventional imunnosuppression (including CNI in four cases), these results demonstrate that insulin independence after islet transplantation can be achieved with a CNI and steroid-free regimen. Such an approach may minimize renal and islet toxicity and thus further improve long-term islet allograft survival.

Background: Atrial fibrillation (AF) occurs frequently after coronary bypass grafting and valve operations. Brain natriuretic peptide (BNP) has been shown to predict recurrence of AF in congestive heart failure. It is a potential biomarker for preoperative risk stratification for development of AF in at-risk patients., Methods: A total of 398 consecutive patients were prospectively evaluated for new-onset AF after heart operations. Patients with a history of AF and presence of permanent pacemaker were excluded. BNP levels were measured before and immediately after the operation., Results: AF occurred in 20%. AF was more likely to develop in patients who were older, who underwent valve operations, had a lower ejection fraction, and a larger left atrial size. Preoperative exposure to statins (62% vs 43%, p < 0.01) and angiotensin inhibitors (60% vs 45%, p = 0.02) was more common in patients without AF. BNP values were insignificantly higher preoperatively (361 vs 302 mg/dL, p = 0.3) and postoperatively (312 vs. 229 mg/dL, p = 0.15) in patients with AF. Multivariate logistic analysis showed that older age (odds ratio [OR], 3.1, 95% confidence interval [CI], 1.7 to 5.6), lower ejection fraction (OR, 2.0; 95% CI, 1.2 to 3.3), larger left atrial size (OR, 3.1; 95% CI, 1.9 to 4.9), and nonuse of angiotensin inhibitors (OR, 2.3; 95% CI, 1.1 to 4.8) were independently associated with AF., Conclusions: This study does not support use of BNP for prediction of AF. Age, low ejection fraction, large left atrial size, and nonuse of angiotensin blocking agents were found to be significant predictors of AF development.

Much is still to be learned about the assessment of simulation-based surgical skills training. However, assessing surgery skills through simulation is a new horizon in medical education. Providing a safe environment for surgical residents to assess their performance rigorously without placing patients in jeopardy is valuable. Using simulators (both warm and cold) as a means to assess trainees has been established. However, also problems concerning the validity and reliability of such simulation-based assessment tools exist, particularly in surgery, that may need to be investigated even more to decide whether to use them as a tool for assessing the performance of surgical residents.

Forty-four adult patients with acute asthma were treated with albuterol at a rate of 15 mg/h over 2 h. Analysis of covariance showed a significantly higher baseline adjusted mean for both percent predicted forced expiratory volume in 1 s (PFEV1) (p = 0.045) and percent predicted forced vital capacity (PFVC) (p = 0.022) at 50 and 110 min for the patients who reported triamcinolone use. Although heart rates decreased overall during the first hour of albuterol treatment, a rise in mean heart rate occurred during the second hour of treatment only in patients reporting triamcinolone use (p = 0.005). After accounting for the effects of parenteral corticosteroids, the effect of reported triamcinolone use remained significant. These data suggest that use of inhaled corticosteroids in this context may be associated with enhanced local and systemic beta-responsiveness, and if a causal relationship could be confirmed, this may constitute yet another advantage of early inhaled corticosteroid treatment in asthma. These data also suggest that chronotropic effects of high-dose albuterol should be monitored in patients using inhaled triamcinolone.