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Nanosecond plasmas in liquids are being used for water treatment, electrolysis, or biomedical applications. The exact nature of these very dynamic plasmas and, most importantly, their ignition physics are strongly debated. The ignition itself may be explained by two competing hypotheses: ignition in water may occur (i) via field effects at the tip of the electrode followed by tunneling of electrons in between water molecules causing field ionization or (ii) via gaseous processes of electron multiplication in nanovoids that are created from liquid ruptures due to the strong electric field gradients. Both hypotheses are supported by theory, but experimental data are very sparse due to the difficulty in monitoring the very fast processes in space and time. In this paper, we analyze nanosecond plasmas in water that are created by applying a positive and a negative polarity to a sharp tungsten electrode. The main diagnostics are fast camera measurements and fast emission spectroscopy. It is shown that plasma ignition is dominated by field effects at the electrode–liquid interface either as field ionization for positive polarity or as field emission for negative polarity. This leads to a hot tungsten surface at a temperature of 7000 K for positive polarity, whereas the surface temperature is much lower for negative polarity. At ignition, the electron density reaches 4 × 10 25 m − 3 for the positive and 2 × 10 25 m − 3 for the negative polarity. At the same time, the emission of the H α light for the positive polarity is four times higher than that for the negative polarity. During plasma propagation, the electron densities are almost identical of the order of 1– 2 × 10 25 m − 3 followed by a decay after the end of the pulse over 15 ns. It is concluded that plasma propagation is governed by field effects in a low density region that is created either by nanovoids or by density fluctuations in supercritical water surrounding the electrode that is created by the pressure and temperature at the moment of plasma ignition. [ABSTRACT FROM AUTHOR]

Nanosecond plasmas in liquids are often generated by applying a short high voltage pulse to an electrode immersed in a liquid for biomedical or environmental applications. The plasmas appear as streamers that propagate through the liquid. The understanding of the ignition of these nanosecond plasmas in liquids, however, is an open question. The occurrence of any traditional gas phase ignition mechanism is unlikely, because the formation of a gas bubble prior to ignition is suppressed by the inertia of the liquid. Therefore, either electron multiplication inside nanopores that are induced by an electric field pressure gradient or field effects at the tip and at the ionization front of the liquid streamer may act as electron generation mechanisms. A deeper understanding can be achieved by comparing the velocity and dynamic of the plasma propagation with modeling, where the individual mechanisms and transport coefficients can be analyzed. Here, we are using intensified charge-coupled device imaging to investigate the time dependence of the streamer dynamic and compare this with a 1D fluid code for negative voltages. It is shown that the maximum streamer length scales with the applied electric field, indicating that an electric stability field in the liquid streamer channel is important, as known for gas streamers. The 1D fluid code can reproduce the proper streamer velocities, if transport coefficients for hydrated electrons are chosen. The model suggests that the propagation of liquid streamers is dominated by the local ionization rate at the ionization front rather than by advection or diffusion of electrons as in gases. This also explains the finding that positive and negative streamers exhibit almost identical electron densities. [ABSTRACT FROM AUTHOR]

Nanosecond plasmas in liquids are an important method to trigger the water chemistry for electrolysis or for biomedical applications in plasma medicine. The understanding of these chemical processes relies on knowing the variation of the temperatures in these dynamic plasmas. This is analyzed by monitoring nanosecond pulsed plasmas that are generated by high voltages at 20 kV and pulse lengths of 15 ns applied to a tungsten tip with 50 μm diameter immersed in water. Plasma emission is analyzed by optical emission spectroscopy ranging from UV wavelengths of 250 nm to visible wavelengths of 850 nm at a high temporal resolution of 2 ns. The spectra are dominated by the black body continuum from the hot tungsten surface and line emissions from the hydrogen Balmer series. Typical temperatures from 6000 K up to 8000 K are reached for the tungsten surface corresponding to the boiling temperature of tungsten at varying tungsten vapor pressures. The analysis of the ignition process and the concurrent spectral features indicate that the plasma is initiated by field ionization of water molecules at the electrode surface. At the end of the pulse, field emission of electrons can occur. During the plasma pulse, it is postulated that the plasma contracts locally at the electrode surface forming a hot spot. This causes a characteristic contribution to the continuum emission at small wavelengths. [ABSTRACT FROM AUTHOR]

Nanosecond plasmas in liquids can initiate chemical processes that are exploited in the fields of water treatment, electrolysis or biomedical applications. The understanding of these chemical processes relies on unraveling the dynamics of the variation of pressures, temperatures and species densities during the different stages of plasma ignition and plasma propagation as well as the conversion of the liquid into the plasma state and the gas phase. This is analyzed by monitoring the emission of nanosecond pulsed plasmas that are generated by high voltages of 20 kV and pulse lengths of 10 ns applied to a tungsten tip with 50 μm diameter immersed in water. The spectra are acquired with a temporal resolution of 2 ns and the emission pattern is modelled by a combination of black body radiation from the hot tungsten tip and the pronounced emission lines of the hydrogen Balmer series. The data indicate two contributions of the hydrogen line radiation that differ with respect to the degree of self-absorption. It is postulated that one contribution originates from a recombination region showing strong self absorption and one contribution from an ionization region showing very little self-absorption. The emission lines from the ionization region are evaluated assuming Stark broadening, that yielded electron densities up to 5 × 1025 m−3. The electron density evolution follows the same trend as the temporal evolution of the voltage applied to the tungsten tip. The propagation mechanism of the plasma is similar to that of a positive streamer in the gas phase, although in the liquid phase field effects such as electron transport by tunneling should play an important role. [ABSTRACT FROM AUTHOR]

Nanosecond plasmas in liquids play an important role in the field of decontamination, electrolysis or plasma medicine. The understanding of these very dynamic plasmas requires information about the temporal variation of species densities and temperatures. This is analyzed by monitoring nanosecond pulsed plasmas that are generated by high voltages (HVs) between 14 and 26 kV and pulse lengths of 10 ns applied to a tungsten tip with 50 μm diameter immersed in water. Ignition of the plasma causes the formation of a cavitation bubble that is monitored by shadowgraphy to measure the dynamic of the created bubble and the sound speed of the emitted acoustic waves surrounding this tungsten tip. The temporal evolution of the bubble size is compared with cavitation theory yielding good agreement for an initial bubble radius of 25 μm with an initial pressure of 5 × 108 Pa at a temperature of 1200 K for a HV of 20 kV. This yields an initial energy in the range of a few 10−5 J that varies with the applied HV. The dissipated energy by the plasma drives the adiabatic expansion of water vapor inside the bubble from its initial supercritical state to a low pressure, low temperature state at maximum bubble expansion reaching values of 103 Pa and 50 K, respectively. These predictions from cavitation theory are corroborated by optical emission spectroscopy. After igniting the nanosecond plasma, the electrical power oscillates in the feed line between HV pulser and plasma chamber with a ring down time of the order of 60 ns. These reflected pulses re-ignite a plasma inside the expanding bubble periodically. Broadband emission due to recombination and Bremsstrahlung becomes visible within the first 30 ns. At later times, line emission dominates. Stark broadening of the spectral lines of Hα (656 nm) and OI (777 nm) is evaluated to determine both the electron density and the electron temperature in these re-ignited plasmas. [ABSTRACT FROM AUTHOR]

Objectives: In a previous study we found an association between antibodies against the human ferritin heavy chain (HFC) protein and giant cell arteritis (GCA) and/or polymyalgia rheumatica (PMR), especially in GCA/PMR patients prior to glucocorticoid treatment. Antibodies against the N-terminal part of ferritin were present in 92% of untreated patients, 69% of patients with disease flare, and 13% of patients in remission. These antibodies appeared to be markers for the early detection of a disease complex usually diagnosed with considerable delay. Our aim in this study was to optimize the diagnostic test by epitope mapping of antibodies against HFC using peptide antigens in enzyme-linked immunosorbent assays (ELISAs). Method: We evaluated serum samples from a selected group of GCA/PMR patients in whom the sensitivity of antibodies against the N-terminal ferritin peptide was only 35%. Patients with late-onset rheumatoid arthritis (LORA), patients with fever, patients with granulomatosis with polyangiitis (GPA), patients without any autoimmune disease at age > 65 years, and blood donors served as controls. Results: By combining different ELISAs we were able to increase the frequency of human ferritin peptide antibodies in GCA/PMR (p < 0.0001) without significantly altering the false-positive rate (FPR) of the diagnostic test. The frequency of antibodies against human ferritin peptide increased from 53% to 74% in GCA/PMR patients with disease flare, from 29% to 40% in GCA/PMR patients in partial remission, and from 8% to 45% in GCA/PMR patients in complete remission. Conclusions: The potential diagnostic test for GCA/PMR can be improved by combining three human ferritin peptide antibodies. [ABSTRACT FROM AUTHOR]

Sarafoglou K, Tridgell AHC, Bentler K, Redlinger-Grosse K, Berry SA, Schimmenti LA. Cardiac conduction improvement in two heterozygotes for primary carnitine deficiency onl-carnitine supplementation. Expanded newborn screening (NBS) for free carnitine levels has led to the identification of a larger number of heterozygous infants of undiagnosed mothers affected with systemic primary carnitine deficiency (PCD), which in turn leads to the identification of other undiagnosed heterozygous family members. There is an increasing recognition that individuals heterozygous for mutations of genes involved in fatty acid oxidation (FAO) may become symptomatic under environmental stress (fasting, prolonged exercise and illness). Considering the importance of carnitine in FAO, its role in heart and bowel function and in lipid metabolism, what is still little known is the phenotypic variability, biochemical parameters and clinical course of PCD heterozygotes with consistently low-to-normal levels to low levels of carnitine over a lifetime. We report on three generations of a family—an asymptomatic PCD heterozygous infant identified through NBS that led to the diagnosis of her asymptomatic PCD-affected mother and the heterozygous status of the maternal grandparents who report some cardiac symptoms that overlap with PCD that improved withl-carnitine supplementation. [ABSTRACT FROM AUTHOR]

This article presents a case study related to double autosomal trisomy. There have been only few reports on double autosomal trisomies. In the given case, mongolism had already been supposed in the newborn period because of the characteristic clinical symptoms. The infant was for the first time admitted to the hospital, at the age of ten weeks since congenital heart defect was suspected. The patient died of bronchopneumonia at thirteen months. According to the electrocardiographic, phonocardiographic and roentgenologic alterations an endocardial cushion defect has been suspected.

Copyright of Humangenetik (00187348) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Humangenetik (00187348) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011. [ABSTRACT FROM PUBLISHER]

Abstract Background Extracellular stimuli in chemotaxis of Escherichia coli and other bacteria are processed by large clusters of sensory complexes. The stable core of these clusters is formed by transmembrane receptors, a kinase CheA, and an adaptor CheW, whereas adaptation enzymes CheR and CheB dynamically associate with the clusters via interactions with receptors and/or CheA. Several biochemical studies have indicated the dependence of the sensory complex stability on the adaptive modification state of receptors and/or on temperature, which may potentially allow environment-dependent tuning of its signalling properties. However, the extent of such regulation in vivo and its significance for chemotaxis remained unclear. Results Here we used fluorescence recovery after photobleaching (FRAP) to confirm in vivo that the exchange of CheA and CheW shows a modest dependency on the level of receptor modification/activity. An even more dramatic effect was observed for the exchange kinetics of CheR and CheB, indicating that their association with clusters may depend on the ability to bind substrate sites on receptors and on the regulatory phosphorylation of CheB. In contrast, environmental temperature did not have a discernible effect on stability of the cluster core. Strain-specific loss of E. coli chemotaxis at high temperature could instead be explained by a heat-induced reduction in the chemotaxis protein levels. Nevertheless, high basal levels of chemotaxis and flagellar proteins in common wild type strains MG1655 and W3110 enabled these strains to maintain their chemotactic ability up to 42°C. Conclusions Our results confirmed that clusters formed by less modified receptors are more dynamic, which can explain the previously observed adjustment of the chemotaxis response sensitivity according to the level of background stimulation. We further propose that the dependency of CheR exchange on the availability of unmethylated sites on receptors is important to improve the overall chemotaxis efficiency by suppressing molecular noise under conditions of high ligand concentrations. Moreover, the observed stability of the cluster core at high temperature is in line with the overall thermal robustness of the chemotaxis pathway and allows maintenance of chemotaxis up to 42°C in the common wild type strains of E. coli.

Background & Aims: In primary biliary cholangitis (PBC), static liver stiffness measurement (LSM) has proven prognostic value. However, the added prognostic value of LSM time course in this disease remains uncertain., Methods: We conducted an international retrospective cohort study among patients with PBC treated with ursodeoxycholic acid and followed by vibration-controlled transient elastography between 2003 and 2022. Using joint modeling, the association of LSM trajectory and the incidence of serious clinical events (SCE), defined as cirrhosis complications, liver transplantation, or death, was quantified using the hazard ratio and its confidence interval., Results: A total of 6362 LSMs were performed in 3078 patients (2007 on ursodeoxycholic acid alone; 13% with cirrhosis), in whom 316 SCE occurred over 14,445 person-years (median follow-up, 4.2 years; incidence rate, 21.9 per 1000 person-years). LSM progressed in 59% of patients (mean, 0.39 kPa/year). After adjusting for prognostic factors at baseline, including LSM, any relative change in LSM was associated with a significant variation in SCE risk (P < .001). For example, the adjusted hazard ratios (95% confidence interval) associated with a 20% annual variation in LSM were 2.13 (1.89-2.45) for the increase and 0.40 (0.33-0.46) for the decrease. The association between LSM trajectory and SCE risk persisted regardless of treatment response or duration, when patients with cirrhosis were excluded, and when only death or liver transplantation was considered., Conclusions: Tracking longitudinal changes in LSM using vibration-controlled transient elastography provides valuable insights into PBC prognosis, offering a robust predictive measure for the risk of SCE. LSM could be used as a clinically relevant surrogate end point in PBC clinical trials., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: Utilization of oocyte donation has become an increasingly common practice in assisted reproductive technology (ART). Since the introduction of larger carrier screening (CS) panels and extended family medical histories (EFMH), studies have not examined how this information factors into the oocyte donor selection process. This exploratory, qualitative study provides further insight into what role, if any, donors' available genetic information (e.g., larger CS panels and EFMH) plays in selecting an oocyte donor., Methods: An online screening survey was distributed to individuals who have undergone or are currently in the process of selecting an oocyte donor through the RESOLVE network and Mayo Clinic's Reproductive Endocrinology and Infertility clinic. From 13 survey respondents, six oocyte recipients subsequently participated in semi-structured telephone interviews and discussed their experiences as oocyte recipients including their perceptions of donors' available genetic information and process in choosing an oocyte donor., Results: Genetic information was seen as valuable and reassuring for participants, particularly EFMH, but did not play a significant role in the selection process for these participants. Supplemental emergent themes provide context on the psychosocial complexities of the oocyte recipient experience and possible explanations for why genetic information is not a decisional priority. Participants indicated genetic information was not extensively discussed or fully explained by providers., Conclusions: Results demonstrate how genetic counselors can be more involved in the pre-selection process to discuss the utility and limitations of genetic information, as well as address psychosocial issues common to the oocyte recipient experience., Competing Interests: Declarations. Human studies and informed consent: All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5). The study was approved by the University of Minnesota and Mayo Medical Centers IRB (protocol 10995 and 20–008436, respectively). Informed consent was obtained from all participants for being included in the study. Animal studies: No animal studies were carried out by the authors for this article. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Bariatric surgery has been shown to improve the histopathological findings in patients with obesity and metabolic dysfunction-associated steatohepatitis, but there are also reports about non-responders or progressive disease after bariatric interventions. Therefore, it is of utmost importance to understand the pathophysiological processes in the liver after bariatric surgery., Materials and Methods: In the present study, 4 weeks old male C57/Bl6 mice were fed a Western Diet to induce metabolic dysfunction-associated steatohepatitis and sleeve-gastrectomy (SG), or sham operation in the pair-fed and ad libitum control group were performed. Mice were observed for two or eight weeks after surgery and metabolic assessment was performed throughout the experiment. Histopathology, flow cytometry and proteomic analyses were conducted to evaluate hepatic inflammation, liver metabolism and affected signaling pathways., Results: Weight loss was higher, and metabolism significantly improved after SG. Two weeks after SG major inflammatory and regulatory disturbances in the liver were observed. The proportion of hepatic CD3 + NK1.1 + cells were decreased, and proteins involved in apoptosis like Fas, Casp1 and Casp9 or in the acute phase response were upregulated in SG mice. These disturbances decreased in the long-term and we observed an increase of many proteins involved in lipid metabolism eight weeks following SG., Conclusions: The rapid weight loss and decrease of hepatic fat after SG lead to a proinflammatory response in the liver in the early phase after surgery, which changes to a more moderate immune response in the long-term. We suggest a preoperative risk stratification and postoperative surveillance depending on the histopathological findings., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Andreas Kroh reports financial support was provided by B. Braun Foundation, Melsungen, Germany. All other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Introduction: In over 50 years since the genetic counseling (GC) profession began, a systematic study of GC communication skills and patient-reported outcomes in actual sessions across multiple clinical specialties has never been conducted. To optimize GC quality and improve efficiency of care, the field must first be able to comprehensively measure GC skills and determine which skills are most critical to achieving positive patient experiences and outcomes. This study aims to characterise GC communication skills using a novel and pragmatic measure and link variations in communication skills to patient-reported outcomes, across clinical specialties and with patients from diverse backgrounds in the USA. Our community-engagement and provider-engagement approach is crucial to develop recommendations for quality, culturally informed GC care, which are greatly needed to improve GC practice., Methods and Analysis: A mixed methods, sequential explanatory design will be used to collect and analyze: audio-recorded GC sessions in cancer, cardiac, and prenatal/reproductive genetic indications; pre-visit and post-visit quantitative surveys capturing patient experiences and outcomes and post-visit qualitative interview data. A novel, practical checklist will measure GC communication skills. Coincidence analysis will identify patterns of GC skills that are consistent with high scores on patient-reported measures. Two-level, multilevel models will be used to evaluate how GC communication skills and other session/patient characteristics predict patient-reported outcomes. Four community advisory boards (CABs) and a genetic counselor advisory board will inform the study design and analysis., Ethics and Dissemination: This study has been approved by the single Institutional Review Board of the University of Minnesota. This research poses no greater than minimal risk to participants. Results from this study will be shared through national and international conferences and through community-based dissemination as guided by the study's CABs. A lay summary will also be disseminated to all participants., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Genetic counselors (GCs) typically provide short-term counseling and assess patient needs, including the need for ongoing psychosocial support. While some patients may benefit from a referral to a mental health provider (MHP), previous research identified barriers to this process due to patient characteristics, the GC work environment, and MHP availability. Adoption of interprofessional collaborative practice (IPCP), a model where multiple healthcare professionals from diverse training disciplines collaborate to deliver patient care, may mitigate these barriers. Evidence suggests that IPCP both increases patient satisfaction and reduces healthcare spending. Anecdotal evidence suggests that GCs and MHPs may use IPCP in select institutions, but there is limited research examining these relationships. This study aims to characterize the benefits, barriers, and limitations of current IPCP practice between GCs and MHPs. Six semi-structured interviews with GCs and MHPs were completed and analyzed thematically. Four themes emerged: (1) mental health concerns in GC sessions and GC scope of practice; (2) establishing and maintaining IPCP between GCs and MHPs; (3) benefits, barriers, and limitations of IPCP; and (4) next steps to develop future IPCP. The findings suggest that there are varying approaches to IPCP that are influenced by perceptions of provider scope of practice. IPCP may mitigate some previously described referral barriers related to logistics, and the availability of trusted MHPs with knowledge of a GCs specialty, thereby improving patient and provider satisfaction., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Genetic counselors are an integral part of the healthcare system; however, the number of genetic counselors in many parts of the United States is limited, impacting access to comprehensive healthcare for all patients. One solution to addressing this deficit includes modifying genetic counseling training programs to increase student enrollment. Fieldwork capacity, driven by a limited number of rotation sites and supervisors, produces a significant bottleneck to entering the profession. Other professions have reported on techniques to increase fieldwork capacity; however, the practicality of these techniques for genetic counseling training has yet to be explored. This study seeks to investigate the perspectives of key stakeholders in genetic counseling training programs on the practicality of techniques already posited in the literature from other allied health professions. Semi-structured focus group interviews with 25 participants were conducted at the 2019 National Society of Genetic Counselors conference. Participants included program directors and supervisors from clinical, industry, and laboratory backgrounds. The focus group responses were analyzed using directed content analysis and a split coding technique, after which several themes emerged within the larger domains of rotation structures, systems infrastructure, skill-building methods, and other novel techniques to increase fieldwork capacity. Emerging themes included the importance of finding quality student placements rather than maximizing the quantity of participatory cases; a need for transparency about the transferability of skills learned from novel experiences; scaffolding student entrustment to expand supervisor capacity; and recognizing nuances in implementation for individual programs. Overall, the results emphasize the importance of openness in communication to manage expectations for students and supervisors, who may be more hesitant to try novel rotation placements and skill-building techniques. Genetic counseling programs may use these results to address the bottleneck of fieldwork capacity, increasing student enrollment., (© 2024 National Society of Genetic Counselors.)

Background and Aims: Normal alkaline phosphatase (ALP) levels in ursodeoxycholic acid (UDCA)-treated patients with primary biliary cholangitis (PBC) are associated with better long-term outcome. However, second-line therapies are currently recommended only when ALP levels remain above 1.5 times the upper limit of normal (×ULN) after 12-month UDCA. We assessed whether, in patients considered good responders to UDCA, normal ALP levels were associated with significant survival gains., Approach and Results: We performed a retrospective cohort study of 1047 patients with PBC who attained an adequate response to UDCA according to Paris-2 criteria. Time to liver-related complications, liver transplantation, or death was assessed using adjusted restricted mean survival time (RMST) analysis. The overall incidence rate of events was 17.0 (95% CI: 13.7-21.1) per 1000 out of 4763.2 patient-years. On the whole population, normal serum ALP values (but not normal gamma-glutamyl transpeptidase (GGT), alanine aminotransferase (ALT), or aspartate aminotransferase (AST); or total bilirubin < 0.6 ×ULN) were associated with a significant absolute complication-free survival gain at 10 years (mean 7.6 months, 95% CI: 2.7 - 12.6 mo.; p = 0.003). In subgroup analysis, this association was significant in patients with a liver stiffness measurement ≥ 10 kPa and/or age ≤ 62 years, with a 10-year absolute complication-free survival gain of 52.8 months (95% CI: 45.7-59.9, p < 0.001) when these 2 conditions were met., Conclusions: PBC patients with an adequate response to UDCA and persistent ALP elevation between 1.1 and 1.5 ×ULN, particularly those with advanced fibrosis and/or who are sufficiently young, remain at risk of poor outcome. Further therapeutic efforts should be considered for these patients., (Copyright © 2023 American Association for the Study of Liver Diseases.)