Hg Resistance Research Articles

Seasonal variation in metabolic profiles and microbial communities in a subarctic ore processing plant.

The mining industry strives to reduce its water footprint by recycling water in ore processing. This leads to build-up of ions, flotation chemicals and microbial biomass, which may affect the process. The Boliden Kevitsa mine in Northern Finland is exposed to seasonal change and recycles up to 90% of the process water. We studied the variation in size, composition and putative functions of microbial communities in summer and winter in the ore processing plant. The raw water, Cu and Ni thickener overflow waters had statistically significantly higher bacterial numbers in winter compared to summer, and specific summer and winter communities were identified. Metagenomic analysis indicated that Cu and Hg resistance genes, sulphate/thiosulphate, molybdate, iron(III) and zinc ABC transporters, nitrate reduction, denitrification, thiosulphate oxidation and methylotrophy were more common in winter than in summer. Raw water drawn from the nearby river did not affect the microbial communities in the process samples, indicating that the microbial communities and metabolic capacities develop within the process over time in response to the conditions in the processing plant, water chemistry, used chemicals, ore properties and seasonal variation. We propose that the microbial community structures are unique to the Boliden Kevitsa mine and processing plant.

Association of pulmonary hypertension with the outcome in patients undergoing edge-to-edge mitral valve repair

ObjectivesThe association of pulmonary hypertension (PH) with the outcome after mitral transcatheter edge-to-edge repair (M-TEER) focusing on the new ESC/ERS guidelines definition for PH.BackgroundPH is frequently found in patients with...

Screening and profiling of mercury-resistant Azotobacter isolated from gold mine tailing in Pongkor, West Java

Mercury (Hg) is a hazardous pollutant produced during the amalgamation of gold extraction. The environmental problems related to improper Hg waste management have become progressively concerning. Hg contamination in environments can be removed by using bioremediation technology. Utilizing Hg-resistant (HgR) microorganisms in Hg bioremediation is a crucial strategy. Azotobacter is one of the potential microbes for Hg bioremediation bioagent due to exopolysaccharides synthesis that binds the heavy metal. The study's main objective was to select and profile a novel Hg-resistant Azotobacter isolated from heavily Hg-contaminated soil and tailing of artisanal and small-scale gold in Pongkor area, West Java, Indonesia. The completely randomized design was used for profiling Azotobacter-HgR and included Hg values of 0, 1, 10, 100, 200, and 400 mg/L. Further, Azotobacter isolate bioassay steps included soil contaminated with Hg, soil contaminated with Hg + Azotobacter sp. S6.a, soil contaminated with Hg + consortium. The profiling results revealed that four Hg-resistant isolates were Azotobacter sp. S5, Azotobacter sp. S6, Azotobacter sp. S6.a, and Azotobacter sp. S9. More importantly, Azotobacter sp. S5 followed by Azotobacter sp. S6.a was found to be the most resistant to Hg exposure at a concentration of 400 mg/L. The Azotobacter sp. S9. produced the lowest EPS, but had the highest activity of nitrogenase and organic acid production. Meanwhile, Azotobacter sp. S6.a. produced the highest EPS. Isolate S5 showed the highest potential as a resistant PGPR-Hg isolate for enhancing the growth of sorghum in Hg-contaminated soil. Sorghum plants accumulate Hg from the soil in the roots but not in the shoots. Present findings suggest that these two isolates have the potential to be used as biological agents to rehabilitate Hg-contaminated soil in Pongkor area.

Pulmonary Vasodilator Therapy in Severe Pulmonary Hypertension Due to Chronic Obstructive Pulmonary Disease (Severe PH-COPD): A Systematic Review and Meta-Analysis.

Background: Chronic obstructive pulmonary disease-associated pulmonary hypertension (PH-COPD) results in a significant impact on symptoms, quality of life, and survival. There is scant and conflicting evidence about the use of pulmonary hypertension (PH) specific therapy in patients with PH-COPD. Study Design and Methods: PubMed, OVID, CINAHL, Cochrane, Embase, and Web of Science were searched using various MESH terms to identify randomized controlled trials (RCTs) or observational studies investigating PH-specific therapies in patients with severe PH-COPD, defined by mean pulmonary artery pressure (mPAP) of more than 35 mm Hg or pulmonary vascular resistance (PVR) of more than 5 woods units on right heart catheterization. The primary outcome was a change in mPAP and PVR. Secondary outcomes were changes in six-minute walk distance (6MWD), changes in the brain-natriuretic peptide (BNP), New York Heart Association (NYHA) functional class, oxygenation, and survival. Results: Thirteen studies satisfied the inclusion criteria, including a total of 328 patients with severe PH-COPD. Out of these, 308 patients received some type of specific therapy for PH. There was a significant reduction in mPAP (mean difference (MD) -3.68, 95% CI [-2.03, -5.32], p < 0.0001) and PVR (MD -1.40 Wood units, 95% CI [-1.97, -0.82], p < 0.00001). There was a significant increase in the cardiac index as well (MD 0.26 L/min/m2, 95% CI [0.14, 0.39], p < 0.0001). There were fewer patients who had NYHA class III/lV symptoms, with an odds ratio of 0.55 (95% CI [0.30, 1.01], p = 0.05). There was no significant difference in the 6MWD (12.62 m, 95% CI [-8.55, 33.79], p = 0.24), PaO2 (MD -2.20 mm Hg, 95% CI [-4.62, 0.22], p = 0.08), or BNP or NT-proBNP therapy (MD -0.15, 95% CI [-0.46, 0.17], p = 0.36). Conclusion: The use of PH-specific therapies in severe PH-COPD resulted in a significant reduction in mPAP and PVR and increased CI, with fewer patients remaining in NYHA functional class III/IV. However, no significant difference in the 6MWD, biomarkers of right ventricular dysfunction, or oxygenation was identified, demonstrating a lack of hypoxemia worsening with treatment. Further studies are needed to investigate the use of PH medications in patients with severe PH-COPD.

Bioremediation of mercury contaminated soil and water: A review

AbstractMercury (Hg) pollution of soil and water environments is a major global threat to human health, agri‐food systems and ecosystems and industrial activities mainly coal combustion augmented their content in different environmental media. Bioremediation is a nature‐based solution involving microbial‐ and plant‐based (phytoremediation) technologies that clean‐up Hg contaminated sites. Here, we review Hg‐resistant bacteria and how latest insights in our understanding of the cellular and biochemical mechanisms of the mer operon genes responsible for Hg resistance and transformation have facilitated developments in microbial Hg‐bioremediation. We also review the phytoremediation mechanisms, including those of bacterial‐ and fungi‐assisted phytoremediation processes, which have shown promising results in reducing Hg2+ to Hg0. This review provides a detailed knowledge of novel Hg bioremediation mechanisms and methods. Consequently, microbial‐ and phyto‐based bioremediation technologies have a critical role in the reclamation of Hg‐contaminated environments and the protection of human health and ecosystems.

Long-term effects of pulmonary endarterectomy on pulmonary hemodynamics, cardiac function, and exercise capacity in chronic thromboembolic pulmonary hypertension

Long-term changes in exercise capacity and cardiopulmonary hemodynamics after pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) have been poorly described. We analyzed the data from 2 prospective surgical CTEPH cohorts in Hammersmith Hospital, London, and Amsterdam UMC. A structured multimodal follow-up was adopted, consisting of right heart catheterization, cardiac magnetic resonance imaging, and cardiopulmonary exercise testing before and after PEA. Preoperative predictors of residual pulmonary hypertension (PH; mean pulmonary artery pressure >20mm Hg and pulmonary vascular resistance ≥2WU) and long-term exercise intolerance (VO2max <80%) at 18months were analyzed. A total of 118 patients (61 from London and 57 from Amsterdam) were included in the analysis. Both cohorts displayed a significant improvement of pulmonary hemodynamics, right ventricular (RV) function, and exercise capacity 6months after PEA. Between 6 and 18months after PEA, there were no further improvements in hemodynamics and RV function, but the proportion of patients with impaired exercise capacity was high and slightly increased over time (52%-59% from 6 to 18months). Long-term exercise intolerance was common and associated with preoperative diffusion capacity for carbon monoxide (DLCO), preoperative mixed venous oxygen saturation, and postoperative PH and right ventricular ejection fraction (RVEF). Clinically significant RV deterioration (RVEF decline >3%; 5 [9%] of 57 patients) and recurrent PH (5 [14%] of 36 patients) rarely occurred beyond 6months after PEA. Age and preoperative DLCO were predictors of residual PH post-PEA. Restoration in exercise tolerance, cardiopulmonary hemodynamics, and RV function occurs within 6months. No substantial changes occurred between 6 and 18months after PEA in the Amsterdam cohort. Nevertheless, long-term exercise intolerance is common and associated with postoperative RV function.

Revisiting Pulmonary Hypertension in the Era of Temporary Mechanical Circulatory Support – Literature Review and Case-Based Discussion

Pulmonary arterial hypertension (PAH) is characterized by persistently increased pressure in the pulmonary arteries. New defining criteria for the different hemodynamic types of pulmonary hypertension (PH) that occur with left heart disease have been proposed by the task force on PH. After consideration of the changes in the general definition of PH in left heart disease, the proposed hemodynamic definition was: (1) isolated postcapillary PH: pulmonary artery wedge pressure >15 mm Hg and mean pulmonary arterial pressure (mPAP) >20 mm Hg and pulmonary vascular resistance (PVR) <3 Woods units (WU); and (2) combined post- and precapillary PH: pulmonary artery wedge pressure >15 mm Hg, mPAP >20 mm Hg, and PVR ≥3 WU. Secondary PH is initially reversible, but eventually, it can become fixed because of the remodeling process of the pulmonary vascular system. Limitations in defining both the time for and amount of reversibility lack clarity. We discuss a case of PH as a framework to better understand these key principles in addressing patients' candidacy for heart or heart-lung transplantation. We performed a literature search for all available contemporary data with the following terms: "pulmonary hypertension," "reversal," "Impella 5.5," "temporary mechanical support," and "LVAD" using the National Library of Medicine - PubMed and PubMed Central between 2019 and 2023. A total of 14 published papers were found with these search. From these, 3 addressed the issue of PH and reversibility in the setting of LHD after durable LVAD placement. No papers were found using Impella 5.5 and PH during this timeframe. Given the paucity of data in the field regarding temporary mechanical circulatory support and pulmonary hypertension, we present a case-based discussion to guide the reader in understanding the potential impact of this method in patients with WHO Class 2 Pulmonary hypertension. A 49-year-old woman with a medical history of acute on chronic biventricular systolic and diastolic heart failure, American College of Cardiology stage D, Stevenson profile C, New York Heart Association class IV (ejection fraction 18%) secondary to nonischemic cardiomyopathy after cardiac resynchronization therapy, pulmonary hypertension, bilateral deep vein thrombosis, and segmental pulmonary embolism presented for heart transplant evaluation. Her cardiac output and central hemodynamics were measured, and she was found to have a pulmonary artery (PA) pressure of 78/38 with a mean PA pressure of 51, pulmonary capillary wedge pressure (PCWP) 30, transpulmonary pressure gradient (TPG) 21, thermodilution cardiac output (CO) 3.35 L/min, and cardiac input (CI) 1.75 L/min/m2. Her PVR was 6.2 WU. Provocative pharmacologic testing for reversibility of PH was performed using sodium nitroprusside, which resulted in a blood pressure of 83/57 (92), heart rate 92/min, and PA pressure of 71/31, with a mean PA pressure of 44 PCWP 22, TPG 22, CO 4.8 L/min, and CI of 2.48 L/min/m2 with a PVR of 4.5 WU. Following this, the patient underwent Impella 5.5 placement through the right axillary artery to optimize afterload reduction and improve end-organ perfusion. Post-Impella hemodynamics on milrinone 0.5 mcg/kg/min demonstrated the following: blood pressure 90/66 (74), heart rate 53/min, and PA pressure of 56/29, with a mean PA pressure of 38, PCWP 24, TPG 14, CO 6 L/min, and CI of 2.9 L/min/m2 with a PVR of 2.3 WU. Left ventricular assist device support with Impella 5.5 is associated with a reduction in mPAP and PVR over weeks to months and thus plays a crucial role as a bridge to transplant. Our case and this review highlights the characteristics of PH resulting from heart failure with reduced ejection fraction and discusses the important clinical issues related to the treatment of these patients. We have shown that left ventricular assist device therapy with Impella 5.5 can effectively reduce left-sided filling pressures and lead to PH improvement. We demonstrate the potential benefits of Impella 5.5 in the management of patients with WHO 2 PH and cardiogenic shock with impaired hemodynamics.

Biochemical and structural basis of mercuric reductase, GbsMerA, from Gelidibacter salicanalis PAMC21136

Heavy metals, including mercury, are non-biodegradable and highly toxic to microorganisms even at low concentrations. Understanding the mechanisms underlying the environmental adaptability of microorganisms with Hg resistance holds promise for their use in Hg bioremediation. We characterized GbsMerA, a mercury reductase belonging to the mercury-resistant operon of Gelidibacter salicanalis PAMC21136, and found its maximum activity of 474.7 µmol/min/mg in reducing Hg+2. In the presence of Ag and Mn, the enzyme exhibited moderate activity as 236.5 µmol/min/mg and 69 µmol/min/mg, respectively. GbsMerA exhibited optimal activity at pH 7.0 and a temperature of 60 °C. Moreover, the crystal structure of GbsMerA and structural comparison with homologues indicated that GbsMerA contains residues, Tyr437´ and Asp47, which may be responsible for metal transfer at the si-face by providing a hydroxyl group (−OH) to abstract a proton from the thiol group of cysteine. The complex structure with NADPH indicated that Y174 in the re-face can change its side chain direction upon NADPH binding, indicating that Y174 may have a role as a gate for NADPH binding. Moreover, the heterologous host expressing GbsMerA (pGbsMerA) is more resistant to Hg toxicity when compared to the host lacking GbsMerA. Overall, this study provides a background for understanding the catalytic mechanism and Hg detoxification by GbsMerA and suggests the application of genetically engineered E. coli strains for environmental Hg removal.

Study of mercury resistance and Fourier transform infrared spectroscopy-based metabolic profiling of a potent Bacillus tropicus strain from forest soil.

Mercury (Hg) is a highly toxic heavy metal and Hg-resistant indigenous bacterial isolates may offer a green and cost-effective bioremediation strategy to counter Hg contamination. In this study, a potent Hg-resistant bacterium was isolated from the forest soil of a bird sanctuary. Identification using matrix-assisted laser desorption ionization-time of flight mass spectrometry depicted the isolate as a strain of Bacillus tropicus, validated by morphological, biochemical, and molecular studies. The isolate demonstrated biological Hg removal efficiency and capacity of 50.67% and 19.76 mg g-1 , respectively. The plasmid borne resistance determinant, merA, encoding mercuric reductase, was detected in the bacterium endowing it with effective Hg volatilization and resistance capability. A Fourier-transform infrared spectroscopic comparative metabolic profiling revealed the involvement of various functional groups like -COOH, -CH2 , -OH, PO4 - and so on, resulting in differential spectral patterns of the bacterium both in control and Hg-exposed situations. A temporal variance in metabolic signature was also observed during the early and mid-log phase of growth in the presence of Hg. The bacterium described in this study is the first indigenous Hg-resistant strain isolated from the Uttar Dinajpur region, which could be further explored and exploited as a potent bioresource for Hg remediation.

DNA hypomethylation-associated transcriptional rewiring enables resistance to heavy metal mercury (Hg) stress in rice

Mercury (Hg) is an important hazardous pollutant that can cause phytotoxicity and harm human health through the food chain. Recently, rice (Oryza sativa L.) has been confirmed as a potential Hg bioaccumulator. Although the genetic and molecular mechanisms involved in heavy metal absorption and translocation in rice have been investigated for several heavy metals, Hg is largely neglected. Here, we analyzed one Hg-resistant line in rice (RHg) derived from a DNA methyltransferase-coding gene, OsMET1–2 heterozygous mutant. Compared with its isogenic wild-type (WT), RHg exhibited a significantly higher survival rate after Hg treatment, ameliorated oxidative damage, and lower Hg uptake and translocation. RNAseq-based comparative transcriptomic analysis identified 34 potential Hg resistance-related genes involved in phytohormone signaling, abiotic stress response, and zinc (Zn) transport. Importantly, the elevated expression of Hg resistance-related genes in RHg was highly correlated with DNA hypomethylation in their putative promoter regions. An ionomic analysis unraveled a negative correlation between Zn and Hg in roots. Moreover, Hg concentration was effectively decreased by exogenous application of Zn in Hg-stressed rice plants. Our findings indicate an epigenetic basis of Hg resistance and reveal an antagonistic relationship between Hg and Zn, providing new hints towards Hg detoxification in plants. Environmental implicationMercury (Hg) as an important hazardous pollutant adversely impacts the environment and jeopardizes human health, due to its chronicity, transferability, persistence, bioaccumulation and toxicity. In this paper, we identified 34 potential genes that may significantly contribute to Hg resistance in rice. We find the expression of Hg resistance-related genes was highly correlated with DNA hypomethylation in their putative promoter regions. Our results also revealed an antagonistic relationship between Hg and Zinc (Zn), providing new hints towards Hg detoxification in plants. Together, findings of this study extend our current understanding of Hg tolerance in rice and are informative to breed seed non–accumulating rice cultivars.

Changes in Pulmonary Hemodynamics Resulted From Long-Term Mechanical Heart Support

Aim To study the dynamics of right ventricular function and pulmonary hemodynamics in patients with pulmonary hypertension during mechanical circulatory support of the heart.Material and methods A retrospective analysis was performed for 25 implantations of left ventricular assist device performed in the Meshalkin National Medical Research Center from 2006 through 2021. Mechanical assist devices were implanted in 21 men and 4 women (median age, 37.5 [29; 48] years). All patients had severe, NYHA functional class III-IV chronic heart failure refractory to the optimal drug therapy. Invasive measurements showed that mean pulmonary arterial pressure (MPAP) was 50 [44.5; 60] mm Hg, transpulmonary pressure gradient (TPG) was 16 [14; 19] mm Hg, and calculated pulmonary vascular resistance was 5.4 [4.9; 9] Wood units, which is an absolute contraindication (TPG &gt;15 mm Hg or pulmonary vascular resistance &gt;5 Wood units) for heart transplantation (HT).Results Duration of left ventricular support was from 17 to 948 days. For 12 (48 %) patients, the HT was performed at 180-948 days following the implantation of left ventricular assist device; 3 patients are presently waiting for HT; 10 patients died from various complications, 6 of them died during the hospital stage. Already during the early stage after the implantation of the mechanical assist device, pulmonary hemodynamics significantly improved. Thus, in one week, MPAP decreased from 50 [44.5; 60] mm Hg to 36 [33; 38] mm Hg (р=0.012) whereas pulmonary vascular resistance decreased from 5.4 [4.9; 9] to 2.9 [2.4; 3.6] Wood units (р=0.008). Follow-up showed further improvement of pulmonary hemodynamics; at 1 month, MPAP was 29 [27; 30] mm Hg and by the time of HT, MPAP was 2.0 [24.8; 26.3] mm Hg (р=0.01), i.e., reached a normal level, which made it possible to perform HT. Similar dynamics was observed for other variables that reflected pulmonary hemodynamics.Conclusion Mechanical support of the heart is able to alleviate manifestations of pulmonary hypertension in most patients with end-stage heart failure. It is necessary to develop an algorithm for identifying the category of patients with a high risk of progression of right ventricular failure.

Abstract 11386: Double Whammy Complicating Management of Pulmonary Hypertension

Introduction: When presented with challenging cardiac cases, in addition to obvious diagnoses, it is critical to maintain high level of suspicion about other subtle conditions. We describe one such case of pulmonary arterial hypertension (PAH) from severe mitral stenosis (MS) and another less obvious congenital cardiac condition that significantly impacted the clinical course. Case: 32-year-old immigrant male with known heart murmur presented with palpitations due to atrial fibrillation. His resting oxygen saturation was 95% in all extremities and he had no clubbing. He had pectus carinatum and scoliosis, prominent right ventricular lift, normal S1, loud S2, opening snap, rumbling diastolic murmur at the apex, and an ejection systolic murmur at the left upper sternal border. Echocardiogram revealed normal biventricular size and function, severely enlarged left atrium, rheumatic severe MS, moderate mitral regurgitation, a restrictive ventricular septal defect (VSD), and elevated right ventricular systolic pressure. Cardiac catheterization demonstrated mixed pre- and post-capillary PAH with mean pulmonary artery pressure of 80 mmHg, wedge pressure 30 mm Hg and pulmonary vascular resistance of 3.0 woods unit which was underestimated. Since pre-capillary component of the PAH could not be entirely explained by the small VSD, a congenital cardiac CT was performed revealing moderate sized patent ductus arteriosus (PDA). Further management decisions were complicated since MS was not amenable to percutaneous intervention and surgical risks were high given severe pre-capillary PAH- management of which with pulmonary vasodilators was itself high risk in the setting of severe MS and high wedge pressures. After optimal medical management, a multidisciplinary team carefully considered the risks and benefits of multiple interventions. Ultimately, the patient underwent surgical mitral valve replacement, fenestrated patch closure of the PDA, and then initiation of pulmonary vasodilators. The patient continues to do well on oral pulmonary vasodilator therapy 6 months after surgery. Conclusion: We describe an astute critical thought process of a multidisciplinary team utilized to manage a challenging case of mixed PAH from severe rheumatic MS and PDA.

Metagenomic Analysis of Urban Wastewater Treatment Plant Effluents in Tokyo.

PurposeUrban wastewater treatment plant (WWTP) effluents, even with proper treatment, may cause antimicrobial resistance (AMR) burden, with a high frequency of acquired antimicrobial resistance genes (ARGs). The dissemination of ARGs into the environment increases the risk of infectious diseases; however, there is little direct evidence regarding their epidemiological effects. This study aimed to assess effluents from urban WWTPs around the Tama River and Tokyo Bay using metagenomic analysis of (AMR) genes (ARGs) and heavy-metal resistance genes.MethodsMetagenomic DNA-seq analysis of water samples and resistome analysis were performed.ResultsThe most prevalent ARG was the sulfonamide resistance gene, sul1, followed by the quaternary ammonium compound resistance gene, qacE, suggesting that basic gene sets (sul1 and ∆qacE) in the class 1 integrons are the predominant ARGs. The aminoglycoside resistance genes, aadA and aph, and macrolide resistance genes, msr(E) and mph(E), were the predominant ARGs against each antimicrobial. blaOXA and blaGES were frequently detected, whereas the blaCTX-M cluster was faintly detected. Non-metric multidimensional scaling plot analysis and canonical correspondence analysis results suggested that marked differences in ARGs could be involved in the seasonal differences; qnrS2, aac(6’)-Ib, and mef(C) increased markedly in summer, whereas msr(E) was more frequently detected in winter. Heavy-metal (Hg and Cu) resistance genes (HMRGs) were significantly detected in effluents from all WWTPs.ConclusionWe characterized a baseline level of the environmental ARG/HMRG profile in the overall community, suggesting that environmental AMR surveillance, particularly in urban WWTPs, is a valuable first step in monitoring the AMR dissemination of bacteria from predominantly healthy individuals carrying notable ARG/Bs.

Sustainability assessment of topsoil ecology in Chongqing, China based on the application of livestock and poultry manure

China is the world's largest livestock and poultry breeding country. Heavy metal trace element additives are widely used to prevent animal diseases and promote their growth. China produces approximately 3.8 billion tons of livestock and poultry manure annually, and untreated livestock and poultry manure causes a large amount of heavy metal elements to enter the soil environment. Currently, there is limited research on the accumulation of heavy metals in the soil due to the continuous application of livestock and poultry manure, the resulting pollution risk and the negative effects on soil ecology sustainability. This study thoroughly investigated the effects of livestock and poultry manure on the composition and function of soil microbial, and heavy metal resistance genes using 16S and metagene sequencing and 6 years of field experiments. The application of livestock and poultry manure for 6 consecutive years increased the accumulation of zinc (Zn), copper (Cu), mercury (Hg), and chromium (Cr) in the soil at the experimental sites, and cadmium (Cd) and Hg had higher potential risk levels (single potential ecological risk coefficients (Eri) of Hg and Cd were 190.49–336.52 and 385.43–468.52, respectively). Firmicutes and Zoopagomycota were significantly correlated with the soil Zn and Cd contents and pH. After continuous application of manure, the relative abundance of Hg resistance genes (merA) in soil increased by 7.3–8.2 times compared with inorganic feitilizer treatment (IF), and Cu resistance genes (copF and actP) increased by 2.45–5.45 times and 3.8–4.6 times. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt2) and metagenomic function prediction indicated that resistance genes, antioxidant response, and metal output played an important role in heavy metal bioresistance and biotransformation. This work presented heavy metal contents, microbial composition and resistance genes in continuous application of livestock and poultry manure in China, and these data will be of great use in the surveillance, maintenance, and biological removal of heavy metals in manure.

Ramping Up the Pressure on the Right Ventricle.

HomeCirculation: Heart FailureVol. 15, No. 6Ramping Up the Pressure on the Right Ventricle Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyRedditDiggEmail Jump toFree AccessResearch ArticlePDF/EPUBRamping Up the Pressure on the Right Ventricle Simone L. Savaris, MD, MSc, Isaac S. Chang, PhD, Stephen P. Wright, MSc, PhD and Susanna Mak, MD, PhD Simone L. SavarisSimone L. Savaris Correspondence to: Simone L. Savaris, MD, MSc, Division of Cardiology, Mount Sinai Hospital, 600 University Ave, Toronto, ON M5G 1X5, Canada. Email E-mail Address: [email protected] https://orcid.org/0000-0002-9049-1805 Division of Cardiology, Mount Sinai Hospital, Toronto, ON, Canada (S.L.S., S.M.). Search for more papers by this author , Isaac S. ChangIsaac S. Chang Mount Sinai Hospital, Toronto, ON, Canada (I.S.C.). Search for more papers by this author , Stephen P. WrightStephen P. Wright Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada (S.P.W.). Search for more papers by this author and Susanna MakSusanna Mak https://orcid.org/0000-0003-2193-602X Division of Cardiology, Mount Sinai Hospital, Toronto, ON, Canada (S.L.S., S.M.). Search for more papers by this author Originally published21 Apr 2022https://doi.org/10.1161/CIRCHEARTFAILURE.122.009671Circulation: Heart Failure. 2022;15Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: April 21, 2022: Ahead of Print A 49-year-old man underwent Heartmate 3 left ventricular assist device implantation as bridge to transplant candidacy for cardiogenic shock due to an ischemic cardiomyopathy which was complicated by a flail mitral valve leaflet resulting in severe regurgitation.Right heart catheterization was performed to assess residual pulmonary hypertension. Right ventricular (RV) and pulmonary artery (PA) pressures were recorded continuously. At baseline, mean PA pressure was 24 mm Hg and pulmonary vascular resistance was 3.0 WU at a speed of 5600 rpm. PA wedge pressure was altered by adjusting speed from 4600 to 5800 rpm. Further increases in speed did not change hemodynamics. Vasoreactivity testing with sodium nitroprusside was also used, based on recent evidence that even mildly elevated PA loading confers increased mortality risk.1,2 Pmax, a theoretical maximal RV systolic pressure derived by extrapolating the isovolumic portions of the waveform, was averaged over 10 cardiac cycles to calculate a single-beat estimate of RV end-systolic elastance, along with PA elastance and the end-systolic elastance:elastance ratio.3The incremental decline in the PA wedge pressure with attenuation of the V wave can be seen as left ventricular assist device speed was increased, and then with infusion of the vasodilator sodium nitroprusside (Figure and Table from left to right). Concomitant reductions in PA pressure and elastance were associated with shortening of the time to peak RVSP, and improved RV-PA coupling as reflected by increasing end-systolic elastance:elastance ratio. Importantly, mixed venous O2 saturation, stroke volume, and cardiac output increased steadily with afterload reduction.Table. Hemodynamics and Values Derived From Single-Beat Estimation of the Ees:Ea RatioUnsupportedRelatively unsupportedBaselineSNP (0.75 μg/kg per min)SNP (1.5 μg/kg per min)Speed4600 rpm5000 rpm5600 rpm5600 rpm5600 rpmMAP, mm Hg9492969065PAWP (a/v/mean), mm Hg18/37/1817/35/1710/24/1011/28/115/9/3PAP (S/D/M), mm Hg51/14/3047/13/2941/10/2441/9/2432/5/17RAP, mm Hg44320PVR, d/s per cm5192200240176168SVR, d/s per cm51532143613781193765MVO2, %61.663.365.168.573.3CO, L/min4.74.95.45.96.8SVi, mL/m2 per beat3941454955RVSP, mm Hg4946424334Time to RVSP, ms318226221210146Pmax, mm Hg166136143147142Ea, mm Hg/mL0.60.470.370.340.2Ees:Ea ratio2.72.73.63.76.7CO indicates cardiac output; Ea, pulmonary artery arterial elastance; Ees, RV end-systolic elastance; MAP, mean arterial pressure; MVO2, mixed venous oxygen saturation; PAP, pulmonary artery pressure; PAWP, pulmonary artery wedge pressure; Pmax, maximal predicted RV pressure; PVR, pulmonary vascular resistance; RAP, right atrium pressure; RV, right ventricle; RVSP, right ventricle systolic pressure; SNP, sodium nitroprusside; SVi, stroke volume index; and SVR, systemic vascular resistance.Download figureDownload PowerPointFigure. The figure shows that with alterations in speed and with a vasodilator challenge (from left to right), pulmonary artery wedge pressure (PAWP) and pulmonary artery pressure (PAP) declined, with measurable changes in the morphology of the right ventricular pressure (RVP) waveform. Pmax, the theoretical maximal RVP, and graphical representations of the coordinates employed for single-beat estimation of RV end-systolic elastance (Ees) are also illustrated. Ea indicates pulmonary artery arterial elastance; Pes, estimated end-systolic pressure; Pmax, maximal predicted RVP; RVSP, right ventricle systolic pressure; SNP, sodium nitroprusside; and SV, stroke volume.This case reinforces the effect of systemic vasodilation and venodilation to optimize hemodynamics in the setting of heart failure with reduced ejection fraction, mitral regurgitation, and a continuous flow left ventricular assist device. The upstream effects of adequate unloading of the left ventricle to improve the function of the RV-PA circulatory unit are also illustrated.Article InformationSources of FundingNone.Disclosures None.FootnotesFor Sources of Funding and Disclosures, see page 645.Correspondence to: Simone L. Savaris, MD, MSc, Division of Cardiology, Mount Sinai Hospital, 600 University Ave, Toronto, ON M5G 1X5, Canada. Email simonelouise.[email protected]ca

Имплантация кольца myoring для коррекции миопии высокой степени у пациента с нистагмом

Purpose. Analysis of clinical and functional results and quality of life after implantation of MyoRing in a patient with high myopia and nystagmus. Material and methods. Patient M., 29 years old, was implanted a myoRing using a femtosecond laser to correct high myopia. Uncorrected visual acuity (UCVA) on the operated eye before surgery was 0.03, corrected visual acuity (CVA) 0.5, spherical refractive component –10.25 D, cylindrical component –4.00 D. Keratometry OD 41.5 × 45.25 × 174°. Corneal hysteresis (CH) was 7.3 mm Hg and corneal resistance factor (CRF) was 6.6 mm Hg. The thickness of cornea in center was 513µm. The data on higher-order aberrations were in line with the generally accepted norm. Observation period – 2 years. Results. 2 years after the operation, visual acuity without correction at OD 0.6, with correction – 0.7. The spherical component was 0.75 D, cylindrical component was –1.25 D. Keratometry OD 30.5 × 31.5 × 171°. Corneal hysteresis was 8.5 mm Hg, corneal resistance factor was 6.9 mm Hg. The thickness of cornea in center was 518µm. All higher-order aberrations decreased, except for vertical Coma (Z3/–1), which increased by 0.35µm, horizontal Coma (Z3/+1), which increased by –0.06µm. According to the results of the questionnaire, the patient noted a significant improvement in visual functions in the period from 3 to 12 months. Problems with the quality of vision in conditions of reduced contrast and complaints of halos were present only in the first months (3–4 months) after surgery. Conclusion. The MyoRing implantation method for correction of high myopia in a patient with nystagmus is highly effective, safe, providing a refractive effect on the spherical and cylindrical component of refraction and enhancing the biomechanical properties of cornea. Keywords: myopia and complex myopic astigmatism, thin cornea, MyoRing ring, femtosecond laser.

The Effect of Borderline Pulmonary Hypertension on Survival in Chronic Lung Disease

Background: The impact of the new “borderline” hemodynamic class for pulmonary hypertension (PH) (mean pulmonary artery pressure [mPAP], 21–24 mm Hg and pulmonary vascular resistance, [PVR], ≥3 wood units, [WU]) in chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) is unclear. Objectives: The aim of this study was to assess the effect of borderline PH (BLPH) on survival in COPD and ILD patients. Method: Survival was analyzed from retrospective data from 317 patients in 12 centers (Italy, Spain, UK) comparing four hemodynamic groups: the absence of PH (NoPH; mPAP <21 mm Hg or 21–24 mm Hg and PVR <3 WU), BLPH (mPAP 21–24 mm Hg and PVR ≥3 WU), mild-moderate PH (MPH; mPAP 25–35 mm Hg and cardiac index [CI] ≥2 L/min/m²), and severe PH (SPH; mPAP ≥35 mm Hg or mPAP ≥25 mm Hg and CI <2 L/min/m²). Results: BLPH affected 14% of patients; hemodynamic severity did not predict survival when COPD and ILD patients were analyzed together. However, survival in the ILD cohort for any PH level was worse than in NoPH (3-year survival: NoPH 58%, BLPH 32%, MPH 28%, SPH 33%, p = 0.002). In the COPD cohort, only SPH had reduced survival compared to the other groups (3-year survival: NoPH 82%, BLPH 86%, MPH 87%, SPH 57%, p = 0.005). The mortality risk correlated significantly with mPAP in ILD (hazard ratio [HR]: 2.776, 95% CI: 2.057–3.748, p < 0.001) and notably less in COPD patients (HR: 1.015, 95% CI: 1.003–1.027, p = 0.0146). Conclusions: In ILD, any level of PH portends worse survival, while in COPD, only SPH presents a worse outcome.

Comparative Metagenomic Study of Rhizospheric and Bulk Mercury-Contaminated Soils in the Mining District of Almadén.

Soil contamination by heavy metals, particularly mercury (Hg), is a problem that can seriously affect the environment, animals, and human health. Hg has the capacity to biomagnify in the food chain. That fact can lead to pathologies, of those which affect the central nervous system being the most severe. It is convenient to know the biological environmental indicators that alert of the effects of Hg contamination as well as the biological mechanisms that can help in its remediation. To contribute to this knowledge, this study conducted comparative analysis by the use of Shotgun metagenomics of the microbial communities in rhizospheric soils and bulk soil of the mining region of Almadén (Ciudad Real, Spain), one of the most affected areas by Hg in the world The sequences obtained was analyzed with MetaPhlAn2 tool and SUPER-FOCUS. The most abundant taxa in the taxonomic analysis in bulk soil were those of Actinobateria and Alphaproteobacteria. On the contrary, in the rhizospheric soil microorganisms belonging to the phylum Proteobacteria were abundant, evidencing that roots have a selective effect on the rhizospheric communities. In order to analyze possible indicators of biological contamination, a functional potential analysis was performed. The results point to a co-selection of the mechanisms of resistance to Hg and the mechanisms of resistance to antibiotics or other toxic compounds in environments contaminated by Hg. Likewise, the finding of antibiotic resistance mechanisms typical of the human clinic, such as resistance to beta-lactams and glycopeptics (vancomycin), suggests that these environments can behave as reservoirs. The sequences involved in Hg resistance (operon mer and efflux pumps) have a similar abundance in both soil types. However, the response to abiotic stress (salinity, desiccation, and contaminants) is more prevalent in rhizospheric soil. Finally, sequences involved in nitrogen fixation and metabolism and plant growth promotion (PGP genes) were identified, with higher relative abundances in rhizospheric soils. These findings can be the starting point for the targeted search for microorganisms suitable for further use in bioremediation processes in Hg-contaminated environments.

Outcome of Surgery for Chronic Thromboembolic Pulmonary Disease without Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious condition that results from incomplete resolution of thromboemboli in pulmonary arteries. Symptomatic patients with chronic thromboembolic disease may have normal hemodynamic at rest. The aim of this study is to evaluate the outcome of pulmonary endarterectomy (PEA) in symptomatic patients with chronic thromboembolic pulmonary disease (CTEPD) in the absence of pulmonary hypertension as currently defined (mean pulmonary artery pressure [mPAP] < 20 mm Hg). Here, we report four symptomatic patients with chronic thromboembolic and normal hemodynamic at rest (mPAP ≤20 mm Hg or 20 < mPAP < 25 mm Hg and pulmonary vascular resistance [PVR] < 240 dyn·s/cm5) who underwent PEA between September 2015 and September 2019. The main outcome measures were functional New York Heart Association class, 6-minute walk distance (6MWD), hemodynamic measures in right heart catheterization (RHC), morbidity, and mortality. There were significant improvement in function class (2.6 ± 0.54 vs. 1 ± 0.2, p = 0.00), mPAP (preoperative: 23.3 ± 0.5 mm Hg vs. postoperative: 18.6 ± 1.5 mm Hg, p = 0.02), 6MWD (preoperative: 378.2 ± 68.7 m vs. postoperative: 432.9 ± 44.5 m, p = 0.01), and PVR (215.33 ± 91 vs. 101 ± 32 dyn·s/cm5, p = 0.1) 6 months after surgery based on data from RHC which was done during exercise. Also, RHC showed a significant decrease in mPAP (preoperative: 37 ± 7.7 mm Hg vs. postoperative 28 ± 3.2 mm Hg, p = 0.06). PEA could improve function class and hemodynamic in patients with CTEPD. Considering hemodynamic improvement in this group of patients after PEA, definition of CTEPH may need to be revised.

Genome-wide locus-specific DNA methylation repatterning may facilitate rapid evolution of mercury resistance in rice.

Albeit a relatively stable epigenetic modification, DNA methylation in plants can be repatterned and play important roles in response to biotic and abiotic stresses. However, whether DNA methylation dynamics may contribute to cope with mercury (Hg) stress in plants remains to be fully investigated. To probe the potential roles of DNA methylation dynamics in coping with Hg stress in rice. Whole-genome bisulfite sequencing was used to profile the DNA methylation patterns of a rice Hg-resistant line (RHg) selected from a heterozygous mutant of the DNA methyltransferase 1 gene (OsMET1+/-), together with its Hg-sensitive wild-type plants of cv. Nipponbare (Nip) under both normal and Hg stress conditions. Genome-wide locus-specific differential methylation regions (DMRs) were detected between RHg and Nip under normal condition, the predominant DMR patterns were CG hypo-DMRs, CHG hypo-DMRs and CHH hyper-DMRs. In both lines, more hyper- than hypo-DMRs were detected at all three sequence contexts (CG, CHG and CHH) under Hg stress relative to normal condition. Comparison of DNA methylation changes in the two lines under Hg stress indicates that RHg had a more dynamic methylome than the control (Nip). Original DMRs in RHg trended to transform to opposite status (from hyper- to hypo- or vice versa) under Hg stress condition. Gene ontology analysis revealed that Hg-resistance-related DMGs were enriched in diverse biological processes. Our results suggest genome-wide locus-specific DNA methylation repatterning can facilitate rapid acquisition of Hg resistance in rice.