Green synthesized silver nanoparticles for iron and manganese ion removal from aqueous solutions.

Microalgae and Cyanobacteria extracts can be used for the synthesis of spherical silver nanoparticles by the reduction of AgNO3 under air atmosphere at room temperature. Here, we synthesized AgNPs using extracts of one cyanobacterium (Synechococcus elongatus) and two microalgae (Stigeoclonium sp. and Cosmarium punctulatum). The nature of the AgNPs was characterized by TEM, HR-TEM, EDS, and UV-Vis. Considering the large quantity of functional groups in the ligands of AgNPs, we suppose they could retain ion metals, which would be useful for water decontamination. Thus, their capacity to adsorb iron and manganese at concentrations of 1.0, 5.0, and 10.0 mg L-1 in aqueous solutions was evaluated. All experiments were performed in triplicate of microorganism extract with no addition of AgNO3 (control) and AgNP colloid (treatment) at room temperature. The ICP analyses showed that the treatments containing nanoparticles were commonly more efficient at removing Fe3+ and Mn2+ ions than the corresponding controls. Interestingly, the smaller nanoparticles (synthesized by Synechococcus elongatus) were the most effective at removing Fe3+ and Mn2+ ions, probably due to their higher surface area:volume ratio. The green synthesized AgNPs proved to be an interesting system for the manufacture of biofilters that could be used to capture contaminant metals in water.

Ross procedure after prosthetic valve thrombosis in a patient with antiphospholipid syndrome and recurrent bleeding.

The Ross procedure allows replacement of a diseased aortic valve with pulmonary root autograft, possibly avoiding the highly thrombotic mechanical valves and immunologic deterioration of tissue valves in antiphospholipid syndrome (APS). Here, we present the use of the Ross procedure in a 42-year-old woman with mild intellectual disability, APS, and a complex anticoagulation history after she presented with thrombosis of her mechanical On-X aortic valve previously implanted for non-bacterial thrombotic endocarditis.

Outcomes of Cardiovascular Surgery Utilizing Heparin versus Direct Thrombin Inhibitors in Cardiopulmonary Bypass in Patients with Previously Diagnosed HIT.

Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of heparin therapy. Heparin is generally avoided in patients with a history of HIT; however, it remains the anticoagulant of choice for cardiac surgery requiring cardiopulmonary bypass (CPB) because of limited experience with alternative anticoagulants such as direct thrombin inhibitors (DTIs) during CPB. We report outcomes of surgery requiring CPB (30-day mortality, rate of thrombosis, and hemorrhage) in patients with prior HIT who received either heparin or a DTI intraoperatively. Seventy-two patients with a prior diagnosis of HIT confirmed by a positive serotonin release assay underwent CBP with a positive HIT antibody at the time of surgery. Thirty-day mortality was 0 and 8.5% in the DTI and heparin cohorts (p = 0.277). Thrombotic events occurred in 1 (7.7%) of the patients treated with DTI and 15 (25.4%) receiving heparin (p = 0.164). In the DTI cohort, 7 (53.8%) had minimal bleeding, 5 (38.5%) had mild bleeding, 1 (7.8%) had moderate bleeding, and none had severe bleeding. In the heparin group, 16 (27.1%) had minimal bleeding, 14 (23.7%) had mild bleeding, 25 (42.4%) had moderate bleeding, and 4 (6.8%) had severe bleeding (p = 0.053). DTI was associated with a lower rate of moderate to severe hemorrhage than heparin (odds ratio 0.097 [95% confidence interval 0.011-0.824], p = 0.033) in a logistic regression model adjusted for thrombocytopenia and length on bypass. DTI appears to be safe in selected patients undergoing CPB after a diagnosis of HIT, and was not associated with higher rates of 30-day mortality, thrombosis, or hemorrhage.

A Novel Diagnostic Algorithm for Heparin-Induced Thrombocytopenia in a Retrospective Cohort of Lung Transplant Recipients.

INTRODUCTION: Heparin-induced thrombocytopenia (HIT) is characterized by thrombocytopenia and potential for thromboembolism. Lung transplant recipients are at risk of developing HIT due to heparin exposure peritransplant. We describe the incidence and impact of HIT in lung transplant recipient index hospital length of stay and survival. DESIGN: A retrospective cohort was obtained from electronic medical records which were queried for all recipients treated with bivalirudin (institutional treatment of choice for HIT) between January 1, 2005, and February 16, 2017 (N = 1171). Patients who developed HIT >30 days after transplant or after their index transplant admission were excluded. A diagnostic algorithm was used retrospectively to determine clinical HIT with an intermediate or high pretest clinical suspicion ("4T" score ≥4) and either (1) positive anti-heparin-platelet-factor 4 (HPF4) assay and a positive functional platelet assay or (2) a positive HPF4 assay only, in patients who did not undergo cardiopulmonary bypass. RESULTS: Among all lung transplant recipients, 2.1% were found to develop HIT in the peritransplant period (N = 25, mean = 88%) with a mean lung allocation score of 50.8 and an incidence of venous thromboembolism of 72%, most upper extremity in location. When matched with historical controls, patients with HIT had a longer overall index hospital length of stay of 43 days (P = .008). There was no difference in short- or long-term survival posttransplant. CONCLUSION: Vigilance for the development of HIT in lung transplant recipients is necessary to prevent further morbidity from thromboembolic events. In our cohort, HIT increased hospital length of stay but did not appear to affect recipient survival.

Anti-Xa assays: What is their role today in antithrombotic therapy?

Although some suggest anti-Xa assays should be the preferred method for monitoring intravenous unfractionated heparin therapy, which method is best is unknown owing to the lack of large randomized controlled trials correlating different assays with clinical outcomes. This article provides an overview of heparin monitoring and the pros, cons, and clinical applications of anti-Xa assays.

Pulmonary thromboendarterectomy in the setting of a mediastinal venous malformation with a congenitally absent left subclavian vein.

Venous malformations have static venous lakes that predispose to spontaneous venous thrombosis within the malformation due to its low-flow static state. Thrombi of varying sizes can then embolize continually into the pulmonary arterial circulation, and occlude and narrow elastic pulmonary arteries causing chronic thromboembolic pulmonary hypertension (CTEPH). Pulmonary thromboendarterectomy (PTE) is potentially curative in CTEPH, but has not been previously reported in the setting of mediastinal and chest wall venous malformations. We report the case of a 21-year-old female with such a large malformation treated successfully with PTE. The patient underwent complete endovascular reconstruction of her subclavian vein system from the axillary vein to the innominate vein stump with covered stent grafts to exclude the malformations from causing recurrent pulmonary emboli. This was followed by embolization of the malformation to allow for the surgical approach. The series of events in this case serves as a novel approach in managing such rare patients.

Glyphosate-Dependent Inhibition of Photosynthesis in Willow.

We studied the physiological mechanisms involved in the deleterious effects of a glyphosate-based herbicide (Factor® 540) on photosynthesis and related physiological processes of willow (Salix miyabeana cultivar SX64) plants. Sixty-day-old plants grown under greenhouse conditions were sprayed with different rates (0, 1.4, 2.1, and 2.8 kg a.e ha-1) of the commercial glyphosate formulated salt Factor® 540. Evaluations were performed at 0, 6, 24, 48, and 72 h after herbicide exposure. We established that the herbicide decreases chlorophyll, carotenoid and plastoquinone contents, and promotes changes in the photosynthetic apparatus leading to decreased photochemistry which results in hydrogen peroxide (H2O2) accumulation. H2O2 accumulation triggers proline production which can be associated with oxidative protection, NADP+ recovery and shikimate pathway stimulation. Ascorbate peroxidase and glutathione peroxidase appeared to be the main peroxidases involved in the H2O2 scavenging. In addition to promoting decreases of the activity of the antioxidant enzymes, the herbicide induced decreases in ascorbate pool. For the first time, a glyphosate-based herbicide mode of action interconnecting its effects on shikimate pathway, photosynthetic process and oxidative events in plants were presented.

Symbiotic association between Salix purpurea L. and Rhizophagus irregularis: modulation of plant responses under copper stress.

There are increasing concerns about trace metal levels such as copper (Cu) in industrial sites and the broader environment. Different studies have highlighted the role of mycorrhizal associations in plant tolerance to trace metals, modulating some of the plant metabolic and physiological responses. In this study, we investigated the role of the symbiotic association betweenRhizophagus irregularisandSalix purpureaL. in modulating plant responses under Cu stress. We measured Cu accumulation, oxidative stress-related, photosynthetic-related and hydraulic traits, for non-inoculated (non-arbuscular mycorrhizal fungi) and inoculated saplings exposed to different Cu concentrations. We found thatS. purpureais a suitable option for phytoremediation of Cu, acting as a phytostabilizer of this trace metal in its root system. We observed that the symbiotic association modulates a broad spectrum of metabolic and physiological responses inS. purpureaunder Cu conditions, including (i) a reduction in gas exchange associated with chlorophyll content changes and (ii) the sequestration of Cu into the cell walls, modifying vessels anatomy and impacting leaf specific conductivity (KL) and root hydraulic conductance (LP). UpholdingKLandLPunder Cu stress might be related to a dynamic Aquaporin gene regulation ofPIP1;2along with an up-regulation ofTIP2;2in the roots of inoculatedS. purpurea.

Stents farmacológicos de segunda geração para tratamento de lesões proximais isoladas da artéria descendente anterior. dados do registro Safira / Second-generation drug-eluting stent treatment for isolated proximal left anterior descending artery stenoses. the Safira registry data

Introdução: A estenose grave do terço proximal da artéria descendente anterior (ADA) é classificada como lesão de alto risco, visto que pode comprometer grande parte do miocárdio ventricular esquerdo. Os stents farmacológicos (SF) de segunda geração têm demonstrado maior eficácia e segurança quando comparados aos não farmacológicos ou aos de primeira geração. São escassos os relatos na literatura do emprego desses dispositivos para o tratamento de lesões isoladas do terço proximal da ADA. Métodos: Estudo observacional e prospectivo, que incluiu pacientes uniarteriais, portadores de lesão de novo no terço proximal da ADA, tratados eletivamente com SF de segunda geração. Avaliamos os desfechos clínicos hospitalares e tardios. Resultados: Foram incluídos 70 pacientes, sendo a maioria do sexo masculino (70%), com média de idades de 65,4 ± 11,2 anos e com alta prevalência de diabetes (37%). O quadro clínico mais frequente foi angina estável (57,1%) e metade das lesões era do tipo B2 ou C. Foram tratadas 70 lesões com 71 stents, com sucesso angiográfico de 100%. O desfecho primário composto por óbito cardíaco, infarto não fatal ou revascularização do vaso alvo no seguimento clínico de 2,5 anos ocorreu em 3% dos pacientes. A mortalidade cardíaca foi de 1,5%, e a revascularização da lesão alvo foi necessária em apenas 1,5% dos pacientes. Conclusões: Em pacientes uniarteriais com lesões de novo da ADA proximal, o tratamento eletivo com SF de segunda geração parece ser uma opção segura, com baixas taxas de eventos cardíacos adversos ou necessidade de nova revascularização

Background: Severe stenosis of the proximal left anterior descending artery (LAD) is classified as a high-risk lesion, as it may affect a large part of the left ventricular myocardium. Second-generation drug-eluting stents (DES) have been shown to be more effective and safer when compared to bare-metal or first-generation ones. There are few reports in the literature on the use of these devices for the treatment of isolated lesions in the proximal LAD. Methods: Observational and prospective study, which included single-vessel patients with de novo lesions in the proximal LAD, electively treated with second-generation DES. In-hospital and late clinical outcomes were evaluated. Results: Seventy patients were included, most of them males (70%), with a mean age of 65.4 ± 11.2 years and a high prevalence of diabetes (37%). The most common clinical presentation was stable angina (57.1%) and half of the lesions were type B2 or C. A total of 70 lesions were treated with 71 stents, with 100% angiographic success. The primary endpoint, consisting of cardiac death, nonfatal infarction, or target-vessel revascularization during the 2.5-year clinical follow-up, occurred in 3% of the patients. Cardiac death was 1.5%, and target-lesion revascularization was required in only 1.5% of the patients. Conclusions: Elective treatment with second-generation DES seems to be a safe option in single-vessel patients with de novo lesions in the proximal LAD, with low rates of adverse cardiac events or need for additional revascularization procedure

External validation of the HIT Expert Probability (HEP) score.

The diagnosis of heparin-induced thrombocytopenia (HIT) can be challenging. The HIT Expert Probability (HEP) Score has recently been proposed to aid in the diagnosis of HIT. We sought to externally and prospectively validate the HEP score. We prospectively assessed pre-test probability of HIT for 51 consecutive patients referred to our Consultative Service for evaluation of possible HIT between August 1, 2012 and February 1, 2013. Two Vascular Medicine fellows independently applied the 4T and HEP scores for each patient. Two independent HIT expert adjudicators rendered a diagnosis of HIT likely or unlikely. The median (interquartile range) of 4T and HEP scores were 4.5 (3.0, 6.0) and 5 (3.0, 8.5), respectively. There were no significant differences between area under receiver-operating characteristic curves of 4T and HEP scores against the gold standard, confirmed HIT [defined as positive serotonin release assay and positive anti-PF4/heparin ELISA] (0.74 vs 0.73, p = 0.97). HEP score ≥ 2 was 100 % sensitive and 16 % specific for determining the presence of confirmed HIT while a 4T score > 3 was 93 % sensitive and 35 % specific. In conclusion, the HEP and 4T scores are excellent screening pre-test probability models for HIT, however, in this prospective validation study, test characteristics for the diagnosis of HIT based on confirmatory laboratory testing and expert opinion are similar. Given the complexity of the HEP scoring model compared to that of the 4T score, further validation of the HEP score is warranted prior to widespread clinical acceptance.

Alteration of plant physiology by glyphosate and its by-product aminomethylphosphonic acid: an overview.

It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyphosate to aminomethylphosphonic acid (AMPA) or be exposed to AMPA from different environmental matrices. AMPA is a recognized phytotoxin, and its co-occurrence with glyphosate could modify the effects of glyphosate on plant physiology. The present review provides an overall picture of alterations of plant physiology caused by environmental exposure to glyphosate and its metabolite AMPA, and summarizes their effects on several physiological processes. It particularly focuses on photosynthesis, from photochemical events to C assimilation and translocation, as well as oxidative stress. The effects of glyphosate and AMPA on several plant physiological processes have been linked, with the aim of better understanding their phytotoxicity and glyphosate herbicidal effects.

Venous thromboembolism in pregnancy.

Low molecular weight heparins (LMWHs) appear to be as safe and effective as unfractionated heparin (UFH) for venous thromboembolic disease (VTED) treatment or prophylaxis during pregnancy. Experience with other parenteral anticoagulant drugs is very limited, and no alternative oral anticoagulants are available to date. In addition to cost, challenges of long-term LMWH use during pregnancy that have not been addressed by controlled clinical trials include a) ideal dosing as pregnancy advances, b) the need for LMWH monitoring by anti-Xa activity levels, and c) ideal therapeutic management as the delivery date nears. Because therapeutic-intensity anticoagulation during pregnancy is challenging, many practitioners favor a more "aggressive" approach toward VTED prophylaxis in women perceived to be at very high risk of thrombosis during pregnancy. Best evidence to date suggests that most women with thrombophilias or with a previous "situational" VTED event probably do not require VTED prophylaxis antepartum, but postpartum anticoagulation prophylaxis is recommended for a few weeks. For those with a history of previous idiopathic VTED or VTED associated with "hormonal challenge" (such as with contraceptive use or previous pregnancy), prophylaxis beginning antepartum may be considered and discussed with the patient. Selected cases of "severe" thrombophilia are probably best managed by initiation of pharmacologic VTED prophylaxis antepartum. However, it must be emphasized that data from prospective controlled clinical trials are lacking.

Risk of venous thromboembolic disease associated with hormonal contraceptives and hormone replacement therapy: a clinical review.

Venous thromboembolic events (VTEs) represent a serious complication related to hormonal contraception and hormone replacement therapy (HRT). Evidence on hormonal contraceptive- and HRT-related VTEs is derived almost exclusively from observational studies and points to a 2- to 6-fold increased relative risk of VTEs with either therapy. Oral contraceptive pills that contain third-generation progestins (desogestrel or gestodene) seem to be associated with greater VTE risk than those that contain levonorgestrel. Oral contraceptive pill use and HRT are associated with exponentially higher VTE relative risks when used by women who carry an inherited hypercoagulable state. The indication of a lower or a lack of VTE risk associated with the use of progestin-only contraceptives and with transdermal HRT suggests that these therapies may be safer than combination oral contraceptive pills and oral HRT for women in whom oral estrogen therapy is considered contraindicated. Data that support such safety advantages are limited and should be interpreted with caution.

The risk of venous thromboembolic disease associated with adjuvant hormone therapy for breast carcinoma: a systematic review.

BACKGROUND: Tamoxifen therapy for patients with breast carcinoma is perceived as an independent risk factor for venous thromboembolic events (VTE), but the risk associated with other adjuvant therapies is less well recognized. METHODS: The authors conducted a computerized PubMed literature search for English-language articles published between January 1966 and December 2003. Studies were analyzed with regard to trial design, breast carcinoma staging, adjuvant agent, definition of VTE outcomes, method of VTE case ascertainment, and the presence of concomitant VTE risk factors. RESULTS: Accurate determination of VTE rates was impaired by the universal lack of routine assessments for asymptomatic VTE. Therefore, only the risk of symptomatic VTE could be derived. The risk of VTE was increased twofold to threefold during tamoxifen or raloxifene use for breast carcinoma chemoprevention. It remains unknown whether the risk is increased further in women with inherited hypercoagulable states. In the setting of early-stage breast carcinoma, the risk of VTE is increased both with tamoxifen use and anastrozole use. Such risk appeared to be lower, albeit not negligible, with anastrozole. Significant methodologic limitations of all available studies in women with advanced-stage breast carcinoma precluded determination of the true VTE risk associated with different adjuvant hormonal agents and made it nearly impossible to compare the risk between different drugs. CONCLUSIONS: All agents used for breast carcinoma chemoprevention and adjuvant therapy appear to increase the risk of VTE. Available data were insufficient to support any assumptions that newer hormonal forms of hormone manipulation are safer than tamoxifen in women with advanced breast carcinoma.

Goal-oriented thrombolytic therapy for venous thromboembolic disease.

The goal of a therapeutic intervention should be to positively impact a meaningful patient outcome. Too often, though, efficacy of a treatment is based on a surrogate endpoint. Thrombolytic therapy for venous thromboembolic disease is an example of a treatment whose success is primarily based on radiographic or echocardiographic endpoints and not endpoints such as symptom relief, functional capacity, quality of life, thrombosis recurrence, and survival. Thrombolysis for lower-extremity deep venous thrombosis does not reduce the incidence of pulmonary embolism, has unclear impact on the rates of post-thrombotic syndrome, and is associated with increased rates of major hemorrhage compared to conventional anticoagulation. Reserving thrombolysis for limb-threatening thrombosis especially in the young seems prudent. Currently available evidence does not support the routine use of thrombolytic therapy in patients with hemodynamically stable pulmonary embolism regardless of right ventricular function status. Risks, benefits, and alternative therapies must always be considered, and therapy must be guided by individual case circumstances and the best available scientific evidence.

Patients with inferior vena caval filters should receive chronic thromboprophylaxis.

A 32-year-old man with testicular carcinoma is diagnosed with an acute left leg deep venous thrombosis (DVT) during his fourth cycle of combination chemotherapy. Because of anticipated moderate to severe thrombocytopenia, anticoagulation is initially avoided and an inferior vena cava (IVC) filter is placed to prevent pulmonary embolism (PE). After completion of all chemotherapy he is deemed to be in remission and anticoagulation is begun. The optimal duration of anticoagulation in this patient is pondered.

Estrogen-containing oral contraceptives are allowable in young women with factor V Leiden heterozygosity without a history of thrombosis.

An 18-year-old woman without significant past medical and surgical history presents to discuss the safety and efficacy of oral contraceptives. She is sexually active and currently relying on condoms alone for birth control. Her cousin had a deep venous thrombosis (DVT) following a pregnancy. As part of the family screening, this patient was identified as a factor V Leiden heterozygote. The risks and benefits of initiating oral contraceptives are discussed.

Hypercoagulable state testing and malignancy screening following venous thromboembolic events.

Mounting interest in hypercoagulability, increased availability of hypercoagulable state test 'panels' and enhanced ability to identify abnormalities in tested patients have prompted widespread testing. Testing for acquired and inherited hypercoagulable states uncovers an abnormality in over 50% of patients presenting with an initial venous thromboembolic event (VTE) but may have minimal actual impact on management in most of these patients. Such laboratory screening should be reserved for patients in whom the results of individual tests will significantly impact the choice of anticoagulant agent, intensity of anticoagulant therapy, therapeutic monitoring, family screening, family planning, prognosis determination, and most of all duration of therapy. Testing 'just to know' is neither cost-effective nor clinically appropriate. The most important testing in patients following acute VTE may be age- and gender-specific cancer screening. Cancer screening following VTE seems most prudent in older individuals and in those with idiopathic VTE and no laboratory evidence for an inherited hypercoagulable state. Cancer screening should focus on identification of treatable cancers and those where diagnosis in an early stage favorably impacts patient survival. Extensive searches for occult malignancy employing whole-body computed tomography and serum tumor markers may identify more cancers but without affecting patient outcome. We advocate that physicians should focus their attention more on VTE prophylaxis and proper treatment and less on costly and, at times, invasive testing of questionable value.

Diagnosis of venous thromboembolic disease in cancer patients.

Venous thromboembolic disease is a common but likely underdiagnosed condition in the cancer patient population. Timely and accurate diagnosis of venous thromboembolism is imperative due to the unacceptable morbidity and mortality associated with a misdiagnosis. Because diagnosis of the condition based on clinical grounds alone is unreliable, physicians should select an appropriate objective diagnostic test to confirm or refute their clinical impressions. Compression duplex ultrasound is the best initial imaging test for both suspected upper- and lower-extremity deep venous thrombosis. Magnetic resonance venography (MRV) is a valid alternative when ultrasound is inconclusive, but contrast venography remains the "gold standard." Suspected pulmonary embolism should be initially evaluated by helical (spiral) computed tomography (CT) or ventilation/perfusion lung scintigraphy, the former being preferred in cases of obvious pulmonary or pleural disease. Indeterminate studies should prompt performance of contrast pulmonary angiography. Inferior vena cava thrombosis is also best assessed by contrast venography, with MRV and CT reserved as alternative imaging modalities. Evidence to date suggests that D-dimer assays remain unreliable in excluding venous thromboembolism in cancer patients. A newer latex agglutination D-dimer assay may prove to be clinically useful in this setting.