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51.
Cold atmospheric plasmas (CAPs) are promising medical tools and are currently applied in dermatology and epithelial cancers. While understanding of the biomedical effects is already substantial, knowledge on the contribution of individual ROS and RNS and the mode of activation of biochemical pathways is insufficient. Especially the formation and transport of short-lived reactive species in liquids remain elusive, a situation shared with other approaches involving redox processes such as photodynamic therapy. Here, the contribution of plasma-generated reactive oxygen species (ROS) in plasma liquid chemistry was determined by labeling these via admixing heavy oxygen 18O2 to the feed gas or by using heavy water H218O as a solvent for the bait molecule. The inclusion of heavy or light oxygen atoms by the labeled ROS into the different cysteine products was determined by mass spectrometry. While products like cysteine sulfonic acid incorporated nearly exclusively gas phase-derived oxygen species (atomic oxygen and/or singlet oxygen), a significant contribution of liquid phase-derived species (OH radicals) was observed for cysteine-S-sulfonate. The role, origin, and reaction mechanisms of short-lived species, namely hydroxyl radicals, singlet oxygen, and atomic oxygen, are discussed. Interactions of these species both with the target cysteine molecule as well as the interphase and the liquid bulk are taken into consideration to shed light onto several reaction pathways resulting in observed isotopic oxygen incorporation. These studies give valuable insight into underlying plasma–liquid interaction processes and are a first step to understand these interaction processes between the gas and liquid phase on a molecular level.

Cold atmospheric plasmas (CAPs) are promising medical tools producing short-lived reactive species.  相似文献   
52.
We present a case of a previously healthy and active 64‐year‐old man who experienced a rapid neuropsychiatric decline. All tests for metabolic causes, neuroinfection, intracranial infarction or tumor were negative. By the means of magnetic resonance imaging, electroencephalography and the anti‐Hu antibody test the patient was diagnosed with paraneoplastic limbic encephalitis related to prostate cancer. The patient died within 6 months. We review the literature on prostate cancer‐related paraneoplastic limbic encephalitis. High‐risk prostate cancer can trigger paraneoplastic limbic encephalitis, a rapidly progressive neurological syndrome with a bad prognosis.  相似文献   
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Objectives. Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. Design. Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. Results. The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. Conclusions. At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.  相似文献   
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Various overoxidized poly(1H-pyrrole) (PPy), poly(N-methylpyrrole) (PMePy) or poly(3,4-ethylenedioxythiophene) (PEDOT) membranes incorporated into an acrylate-based solid polymer electrolyte matrix (SPE) were directly electrosynthesized by a two-step in situ procedure. The aim was to extend and improve fundamental properties of pure SPE materials. The polymer matrix is based on the cross-linking of glycerol propoxylate (1PO/OH) triacrylate (GPTA) with poly(ethylene glycol) diacrylate (PEGDA) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a conducting salt. A self-standing and flexible polymer electrolyte film is formed during the UV-induced photopolymerization of the acrylate precursors, followed by an electrochemical polymerization of the conducting polymers to form a 3D-IPN. The electrical conductivity of the conducting polymer is destroyed by electrochemical overoxidation in order to convert the conducting polymer into an ion-exchange membrane by introduction of electron-rich groups onto polymer units. The resulting polymer films were characterized by scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, differential scanning calorimetry, thermal analysis and infrared spectroscopy. The results of this study show that the combination of a polyacrylate-matrix with ion selective properties of overoxidized CPs leads to new 3D materials with higher ionic conductivity than SPEs and separator or selective ion-exchange membrane properties with good stability by facile fabrication.

Conductive polymers were encapsulated and subsequently overoxidized in an acrylate polymer matrix as potential separator materials via the combination of UV-induced and electrochemical polymerization.  相似文献   
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58.
Background

It remains unknown whether laparoscopic compared to open surgery translates into fewer incisional hernia repairs (IHR). The objectives of the current study were to compare the long-term incidence of IHR and the size of repaired hernias between patients subjected to laparoscopic or open resection of colonic cancer.

Methods

This was a nationwide cohort study comprised of patients undergoing resection for colonic cancer between January 2007 and March 2016 according to the Danish Colorectal Cancer Group database. Patients who subsequently underwent IHR were identified in the Danish Ventral Hernia Database, from which information about the priority of the hernia repair and the size of the fascial defect was retrieved.

Results

The study included 17,717 patients, of whom 482 (2.7%) underwent subsequent IHR during a median follow-up of 4.7 (interquartile range 2.8–6.9) years. There was no significant difference in the 5-year cumulative incidence of hernia repair after laparoscopic compared to open colonic resection (3.9%, CI 3.3–4.4% vs 4.1%, CI 3.5–4.6%). After adjustment for confounders, laparoscopic approach was associated with an increased rate of emergency IHR (HR 2.37, 95% CI 1.03–5.46, P = 0.042) as opposed to elective IHR (HR 0.91, 95% CI 0.73–1.14, P = 0.442). Laparoscopic surgery was significantly associated with a decreased fascial defect area compared to open surgery (mean difference −16.0 cm2, 95% CI −29.4 to −2.5, P = 0.020).

Conclusions

There was no difference in the incidence of IHR after open compared to laparoscopic resection. Compared to the open approach, laparoscopic resection increased the rate of subsequent emergency IHR, suggesting that a more aggressive therapeutic approach may be warranted in this patient group upon diagnosis of an incisional hernia.

  相似文献   
59.
Immune-mediated bone loss significantly impacts fracture risk in patients with autoimmune disease, but to what extent individual variations in immune responses affect fracture risk on a population level is unknown. To examine how immune responses relate to risk of hip fracture, we looked at the individual variation in a post-vaccination skin test response that involves some of the immune pathways that also drive bone loss. From 1963 to 1975, the vast majority of the Norwegian adult population was examined as part of the compulsory nationwide Norwegian mass tuberculosis screening. These examinations included standardized tuberculin skin tests (TSTs). Our study population included young individuals (born 1940 to 1960 and aged 14 to 30 years at examination) who had all received Bacille Calmette-Guerin (BCG) vaccination after a negative TST at least 1 year prior and had no signs of tuberculosis upon clinical examination. The study population ultimately included 244,607 individuals, whose data were linked with a national database of all hospitalized hip fractures in Norway from 1994 to 2013. There were 3517 incident hip fractures during follow-up. Using a predefined Cox model, we found that men with a positive or a strong positive TST result had a 20% (hazard ratio [HR] = 1.20, 95% confidence interval [CI] 1.01–1.44) and 24% (HR = 1.24, 95% CI 1.03–1.49) increased risk of hip fracture, respectively, compared with men with a negative TST. This association was strengthened in sensitivity analyses. Total hip bone mineral density (BMD) was available for a limited subsample and similarly revealed a non-significantly reduced BMD among men with a positive TST. Interestingly, no such clear association was observed in women. An increased immune response after vaccination is associated with an increased risk of hip fracture decades later among men, possibly because of increased immune-mediated bone loss. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
60.
Oxytocin (OT) and arginine vasopressin (AVP) exert robust influence on social affiliation and specific cognitive processes in healthy individuals. Abnormalities in these neuroendocrine systems have been observed in psychotic disorders, but their relation to impairments in behavioral domains that these endocrines modulate is not well understood. We compared abnormalities of OT and AVP serum concentrations in probands with schizophrenia (n = 57), schizoaffective disorder (n = 34), and psychotic bipolar disorder (n = 75); their first-degree relatives without a history of psychosis (n = 61, 43, 91, respectively); and healthy controls (n = 66) and examined their association with emotion processing and cognition. AVP levels were lower in schizophrenia (P = .002) and bipolar probands (P = .03) and in relatives of schizophrenia probands (P = .002) compared with controls. OT levels did not differ between groups. Familiality estimates were robust for OT (h 2 = 0.79, P = 3.97e−15) and AVP (h 2 = 0.78, P = 3.93e−11). Higher levels of OT were associated with better emotion recognition (β = 0.40, P < .001) and general neuropsychological function (β = 0.26, P = .04) in healthy controls as expected but not in any proband or relative group. In schizophrenia, higher OT levels were related to greater positive symptom severity. The dissociation of OT levels and behavioral function in all proband and relative groups suggests that risk and illness factors associated with psychotic disorders are not related to reduced OT levels but to a disruption in the ability of physiological levels of OT to modulate social cognition and neuropsychological function. Decreased AVP levels may be a marker of biological vulnerability in schizophrenia because alterations were seen in probands and relatives, and familiality was high.Key words: oxytocin, vasopressin, schizophrenia, bipolar disorder, emotion recognition  相似文献   
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