Asymmetric Dimethylarginine in Hemodialysis,Hemodiafiltration, and Peritoneal Dialysis

Asymmetric dimethylarginine (ADMA) is a mediator of endothelial dysfunction. Production and elimination of ADMA may be affected by the type of renal replacement therapy used and oxidative stress. Plasma ADMA, advanced glycation end products (AGE), and homocysteine were assessed in 59 subjects: 20 hemodialysis (HD) patients, 19 patients undergoing peritoneal dialysis (PD), and 20 controls. Results were compared between the groups. The effect of 8 weeks of HD and high‐volume predilution hemodiafiltration (HDF) was compared in a randomized study. HD patients showed higher ADMA (1.20 [0.90–1.39 µmol/L]) compared to controls (0.89 [0.77–0.98], P < 0.01), while ADMA in PD did not differ from controls (0.96 [0.88–1.28]). AGE and homocysteine were highest in HD, lower in PD (P < 0.01 vs. HD), and lowest in controls (P < 0.001 vs. HD and PD). PD patients had higher residual renal function than HD (P < 0.01). The decrease in ADMA at the end of HD (from 1.25 [0.97–1.33] to 0.66 [0.57–0.73], P < 0.001) was comparable to that of HDF. Switching from HD to HDF led to a decrease in predialysis homocysteine level in 8 weeks (P < 0.05), while ADMA and AGE did not change. Increased ADMA levels in patients undergoing HD, as compared to PD, may be caused by higher oxidative stress and lower residual renal function in HD. Other factors, such as diabetes and statin therapy, may also be at play. The decrease in ADMA at the end of HD and HDF is comparable. Switching from HD to HDF decreases in 8 weeks the predialysis levels of homocysteine without affecting ADMA.     

Routine screening for pulmonary embolism in COVID-19 patients at the emergency department: impact of D-dimer testing followed by CTPA

Journal of Thrombosis and Thrombolysis - COVID-19 patients have increased risk of pulmonary embolism (PE), but symptoms of both conditions overlap. Because screening algorithms for PE in COVID-19...     

A single methamphetamine administration rapidly decreases vesicular dopamine uptake

Recent studies demonstrated that vesicular dopamine (DA) uptake can be rapidly altered in synaptic vesicles purified from the striata of stimulant-treated rats. Specifically, a single administration of the plasmalemmal DA transporter inhibitor, cocaine, or the DA D(2) agonist, quinpirole, increases vesicular DA uptake in vesicles purified from the striata of treated rats. These effects of cocaine are prevented by pretreatment with a D(2), but not D(1), DA receptor antagonist. The purpose of the present study was to characterize the effect of a mechanistically different psychostimulant, methamphetamine (METH), on vesicular DA uptake. Results demonstrated that a single administration of this DA-releasing agent rapidly and reversibly decreased vesicular DA uptake. The METH-related decrease in vesicular DA uptake was attenuated by pretreatment with the D(2) antagonist, eticlopride, but not the D(1) antagonist, SCH23390 (R-[+]-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine). Core body temperature did not contribute to the effects of METH on vesicular DA uptake. Neither quinpirole nor cocaine increased vesicular DA uptake when rats were concurrently treated with METH. These studies provide further evidence that psychostimulants rapidly and differentially modify vesicular DA uptake. In addition, these studies demonstrate a complex role for D(2) DA receptors in altering vesicular DA transport.     

New probabilistic risk assessment of ethylhexyl methoxycinnamate: Comparing the genotoxic effects of trans‐ and cis‐EHMC

Ethylhexyl methoxycinnamate (EHMC) is a widely used UV filter present in a large number of personal care products (PCPs). Under normal conditions, EHMC occurs in a mixture of two isomers: trans‐EHMC and cis‐EHMC in a ratio of 99:1. When exposed to sunlight, the trans isomer is transformed to the less stable cis isomer and the efficiency of the UV filter is reduced. To date, the toxicological effects of the cis‐EHMC isomer remain largely unknown. We developed a completely new method for preparing cis‐EHMC. An EHMC technical mixture was irradiated using a UV lamp and 98% pure cis‐EHMC was isolated from the irradiated solution using column chromatography. The genotoxic effects of the isolated cis‐EHMC isomer and the nonirradiated trans‐EHMC were subsequently measured using two bioassays (SOS chromotest and UmuC test). In the case of trans‐EHMC, significant genotoxicity was observed using both bioassays at the highest concentrations (0.5 ‐ 4 mg mL^?1). In the case of cis‐EHMC, significant genotoxicity was only detected using the UmuC test at concentrations of 0.25 ‐ 1 mg mL^?1. Based on these results, the NOEC was calculated for both cis‐ and trans‐EHMC, 0.038 and 0.064 mg mL^?1, respectively. Risk assessment of dermal, oral and inhalation exposure to PCPs containing EHMC was carried out for a female population using probabilistic simulation and by using Quantitative in vitro to in vivo extrapolation (QIVIVE). The risk of cis‐EHMC was found to be ～1.7 times greater than trans‐EHMC. In the case of cis‐EHMC, a hazard index of 1 was exceeded in the 92nd percentile. Based on the observed differences between the isomers, EHMC application in PCPs requires detailed reassessment. Further exploration of the toxicological effects and properties of cis‐EHMC is needed in order to correctly predict risks posed to humans and the environment. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 569–580, 2017.     

Thyroid surgery in children and adolescents

Authors present 114 children and adolescents of the total 3865 patients that underwent surgery on the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University, Prague, Department of Otorhinolaryngology of IPVZ, Prague because of a thyroid disease in years 1991-2000. The male/female ratio in the group was 1:6.5, 16 (13.9%) males and 99 (86.1%) females. For non-malignant disease, the male/female ratio was 1:6.5 and for malignant disease, it was 1:5.4. Thyroid surgery was indicated for non-malignant disease in 82 (71.9%) cases--11 males and 71 females. Most frequently it was indicated because of Graves-Basedow and Hashimoto toxicosis--in 39 children (34.2%), in 5 children (4.4%) for toxic adenoma. Because of the polynodular goiter surgery was indicated in 13 cases (11.4%), in 22 cases (19.3%) for mononodular goiter. Three girls (2.6%) were recommended for surgery because of Hashimoto thyreoiditis and for mechanic syndrome in diffuse goiter one girl (0.9%). Malignant tumor was found in 32 children (28.1%)--5 males and 27 females. Most frequent histological type was papillary cancer--in 25 cases (21.9%). Follicular cancer was diagnosed in four cases (3.5%) and medullar cancer in three cases (2.6%). TNM classification in children and adults is summarized in Table 1. Surgery was carried out in two children with distant metastases (lung localization). In both children the pre-disease stage lasted more than 12 months. The first manifestation of the disease was a finding of enlarged and palpable nodes on the neck. The authors summarize indications for surgery of thyroid diseases in children and adolescents. A treatment of the thyroid gland is a teamwork. Indication for surgery is carried out by a pediatric endocrinologist in cooperation with a surgeon specialized in thyroid surgery. The possible identification of the recurrent laryngeal nerve by a surgery microscope is an unquestionable advance. Children and adults should be centralized into health-care centers capable not only of surgery, but also of endocrinology care. In children with a malignant disease there is a need for cooperation with a pediatric oncologist and a following oncological treatment on a nuclear medicine department. The authors summarize the information about today's thyroid surgery care possibilities for children and adolescents. They point out the differences in indications and the decision about extent of surgery in children and adolescents.     

Biological activities of Prunella vulgaris extract

The organic fraction (OF; 25.7% w/w of rosmarinic acid) of Prunella vulgaris (total extract) was found to exhibit the following: scavenging activity on diphenylpicrylhydrazyl radical (DPPH), inhibition of in vitro human LDL Cu(II)-mediated oxidation, protection of rat mitochondria and rat hepatocytes exposed to either tert-butyl hydroperoxide, or to Cu(II) and Fe(III) ions. OF also showed a potential to inhibit rat erythrocyte haemolysis and it reduced the production of LTB(4) in bovine PMNL generated by the 5-lipoxygenase pathway. Other observations included antiproliferative effects against HaCaT cells and mouse epidermal fibroblasts and a moderate OF antimicrobial activity on gram-positive bacteria. Rosmarinic, caffeic and 3-(3,4-dihydroxyphenyl)lactic acids exhibited less potent activity than the plant extract in all bioassays. The antioxidative, antimicrobial, together with antiviral effects offer good prospects for the medicinal applications of P. vulgaris.     

Knochenkontinuitätstrennungen durch Stromwirkung

Zusammenfassung In der Arbeit wird auf die Möglichkeit von Knochenkontinuitätstrennungen durch Stromwirkung aufmerksam gemacht. Solche Knochenschäden sind auf einem indirekten (durch Muskelzug) oder direkten Wege möglich. Die praktisch wichtigsten Formen unter 168 eigenen Verletzten mit positivem Knochenbefund werden beschrieben und in einigen klinischen Beobachtungen und Röntgenbildern dokumentiert. Die Prognose solcher Knochenschäden ist relativ günstig, ihre Anwesenheit muß jedoch festgestellt werden, sonst können durch ihre Vernachlässigung Komplikationen und Dauerzustände entstehen, die für das weitere Schicksal des Kranken ungünstig und dabei überflüssig sind.Mit 15 Textabbildungen     

Asymmetric dimethylarginine, homocysteine and renal function--is there a relation?

The adverse effect of hyperhomocysteinemia on the vascular wall can be partially explained by increasing plasma concentration of asymmetric dimethylarginine (ADMA), a potent inhibitor of nitric oxide synthase. The aim of the study was to compare ADMA and homocysteine levels in three groups of subjects: blood donors with normal homocysteine concentration (group A), patients with hyperhomocysteinemia and normal kidney function (group B) and hemodialysis patients who are known to be hyperhomocysteinemic (group C). Concentrations of homocysteine (enzymatic method), ADMA (enzyme-linked immunoassay) and creatinine (Jaffe method) in EDTA plasma were measured. Plasma ADMA levels were significantly higher in both groups with hyperhomocysteinemia (1.60+/-0.56 micromol/L in group B, 1.81+/-0.57 micromol/L in group C) when compared with those in blood donors (0.82+/-0.29 micromol/L, p<0.001 in both cases). Significant positive correlations were found between concentrations of ADMA and homocysteine (r=0.42, p<0.0001), ADMA and creatinine (r=0.39 p<0.001), homocysteine and creatinine (r=0.69, p<0.0001), age and homocysteine (r=0.47, p<0.001), age and ADMA (r=0.57, p<0.001) and age and creatinine (r=0.37, p<0.001). Increased ADMA concentrations in hyperhomocysteinemic patients were confirmed, but multiple linear regression analysis showed that this significant correlation is only apparent due the dependence of both parameters on age.     

Open lung surgery with Nd-YAG Laser

We report on nineteen patients who successfully underwent open lung performance with a Nd-YAG laser in the period December 1987 to August 1988. Reasons for laser operations were lung metastases (twelve cases), lung fibrosis (five patients), one lung cyst and one tuberculoma. We used the Nd-YAG laser in non-contact mode, with focus hand-piece spot size of 1.5 mm, a continual 1064 nm wavelength and a power output 90 W. In these nineteen cases we performed 35 laser photoablations of lung tissue. All patients healed without any serious complications. The major advantage of Nd-YAG laser beam in open lung surgery is in the rapid sealing effect of small airways and of blood vessels up to 3 mm. The Nd-YAG laser seems to be very suitable for operations in lung periphery.