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To investigate how physics students perceived the sudden shift to online learning at the beginning of COVID-19 pandemic, 18 semistructured interviews were conducted with university students in Austria, Croatia, and Germany. Based on the interviews, a questionnaire was developed and data from N ¼ 578 physics students from five universities in Germany, Austria, and Croatia were gathered. In this paper, we report how students perceived synchronous and asynchronous physics lessons, how their perception correlates with their self-organization skills, which activities and teaching methods were perceived as helpful, and what are the implications for future physics courses. The most common advantages of synchronous course elements reported by students were the possibility to immediately ask questions, the feeling of community and interaction with other students, and the defined daily structure, whereas the most common advantages of asynchronous course elements reported were flexible time management and the possibility to watch videos at their own pace. The data indicate a correlation between preference for synchronous courses and their general self-organization, so instructors should be aware of this connection when planning future courses. Face-to-face lectures at university were perceived as the most helpful course element, followed by the recorded lectures from the instructor and the group work on the assignments, projects, and problems with other students. Furthermore, our results suggest that most students would in the future like to preserve the upload of learning materials and recorded video of the lectures in addition to classroom lectures. Overall, the results of this study suggest that both synchronous and asynchronous course elements should be combined in future online and in-person physics courses.

The COVID-19 pandemic has significantly affected the education system worldwide, which was forced to respond with a sudden shift to distance learning. While successful distance teaching requires careful thinking, planning, and the development of technological and human resources, there was no time for preparation in the current situation. Various physics courses, including lectures, tutorials, and laboratory courses, had to be transferred to online formats, resulting in a variety of simultaneous, asynchronous, and mixed activities. To investigate how physics students perceived the sudden shift to online learning, we developed a questionnaire and gathered data from N = 578 physics students from five universities in Germany, Austria, and Croatia. In this article, we report how the problem-solving sessions (recitations) and laboratories were adapted, how students judge the different formats of the courses, and how useful and effective they perceived them. The results are correlated with the students' self-efficacy ratings and other behavioral measures (such as self-regulated learning skills). This study is descriptive in nature, and a survey study design was implemented to examine the relationships among the variables. We found that good communication abilities (r = 0.48, p < 0.001) and self-organization skills (r = 0.63, p < 0.001) are positively correlated with perceived learning achievement. Furthermore, the previous duration of studies had a significant impact on several self-reported achievement measures, resulting in consistently lower scores of students in their first academic year compared with students who were further along academically. We draw conclusions and suggest implications for future online classes on the instructor and faculty level. Suggestions include (i) focusing on first-year courses with on-campus teaching when facing limited lecture hall capacities, (ii) offering special courses for promoting self-regulated learning skills, (iii) emphasizing the positive aspects of distance learning, and (iv) installing networking services for supporting student communication.

At the universities of Dresden, Vienna, and Zagreb, a laboratory course for prospective physics teachers was transferred to an online environment because of the lockdown in March 2020 due to the COVID-19 pandemic. The aim of this paper is to present and compare students’ and instructors’ considerations about the experiences with this laboratory course at these three universities and to formulate guidelines for organizing lab courses for prospective physics teachers. The research was conducted in three steps: first, interviews were conducted with prospective physics teachers (N = 10); second, an online questionnaire was administered to course participants (N = 99); and third, lab course instructors completed an online questionnaire (N = 8). The results show that an increase in creativity and confidenc e was expressed when conducting home experiments. Students who received support and guidance benefited more from the online lab course, but some students also experienced a greater time commitment. On a positive note, all participants thought outside-the-box during this lab experience and found solutions that led to new ways of conducting labs. Our study suggests that in future online or regular lab courses, students should have the chance to make decisions about experiments and be creative, with an emphasis on peer discussions and support from instructors. [ABSTRACT FROM AUTHOR]

Alveolar echinococcosis is an emerging zoonotic disease caused by the parasite Echinococcus multilocularis. Most patients are diagnosed at a late stage, when lifelong treatment with benzimidazoles is required to stop disease progression. However, for patients who do not tolerate benzimidazole therapy, there are no alternatives. Here, we present a patient with advanced alveolar echinococcosis who was successfully treated with amphotericin B deoxycholate and mefloquine as a rescue therapy after he developed albendazole intolerance.

Non-alcoholic fatty liver disease (NAFLD) is identified as a risk factor for developing severe COVID-19. While NAFLD is associated with chronic low-grade inflammation, mechanisms leading to immune system hyperactivation remain unclear. The aim of this prospective observational study is to analyze cytokine profiles in patients with severe COVID-19 and NAFLD. A total of 94 patients with severe COVID-19 were included. Upon admission, clinical and laboratory data were collected, a liver ultrasound was performed to determine the presence of steatosis, and subsequently, 51 were diagnosed with NAFLD according to the current guidelines. There were no differences in age, sex, comorbidities, and baseline disease severity between the groups. Serum cytokine concentrations were analyzed using a multiplex bead-based assay by flow cytometry. Upon admission, the NAFLD group had higher C-reactive protein, procalcitonin, alanine aminotransferase, lactate dehydrogenase, and fibrinogen. Interleukins-6, -8, and -10 and CXCL10 were significantly higher, while IFN-γ was lower in NAFLD patients. Patients with NAFLD who progressed to critical illness had higher concentrations of IL-6, -8, -10, and IFN-β, and IL-8 and IL-10 appear to be effective prognostic biomarkers associated with time to recovery. In conclusion, NAFLD is associated with distinct cytokine profiles in COVID-19, possibly associated with disease severity and adverse outcomes.

Human gut-associated lymphoid tissues (GALT) play a key role in the acute phase of HIV infection. The propensity of HIV to replicate in these tissues, however, is not fully understood. Access and migration of naive and memory CD4 + T cells to these sites is mediated by interactions between integrin α 4 β 7 , expressed on CD4 + T cells, and MAdCAM, expressed on high endothelial venules. We report here that MAdCAM delivers a potent costimulatory signal to naive and memory CD4 + T cells following ligation with α 4 β 7 . Such costimulation promotes high levels of HIV replication. An anti-α 4 β 7 mAb that prevents mucosal transmission of SIV blocks MAdCAM signaling through α 4 β 7 and MAdCAM-dependent viral replication. MAdCAM costimulation of memory CD4 + T cells is sufficient to drive cellular proliferation and the upregulation of CCR5, while naive CD4 + T cells require both MAdCAM and retinoic acid to achieve the same response. The pairing of MAdCAM and retinoic acid is unique to the GALT, leading us to propose that HIV replication in these sites is facilitated by MAdCAM-α 4 β 7 interactions. Moreover, complete inhibition of MAdCAM signaling by an anti-α 4 β 7 mAb, an analog of the clinically approved therapeutic vedolizumab, highlights the potential of such agents to control acute HIV infection.

The homing of lymphocytes to the mucosa is mainly controlled by α4β7 integrin, and it is amplified during gut chronic inflammation, as occurs with HIV and/or inflammatory bowel diseases. We designed and applied an improved immunization strategy based on an innovative selection process to isolate new α4β7 lymphocyte-specific monoclonal antibodies that are able to prevent their migration into inflamed gut tissues and/or to counteract HIV infection in vitro. First, 5 monoclonal antibodies (1 IgA, 1 IgM, and 4 IgGs) were selected based on their capacity to recognize α4 or β7 homodimers and α4β7 heterodimers in transfected human cells. Their ability to block gp120/α4β7 or MAdCAM-1/α4β7 interactions was then measured in vitro with human T and B lymphocytes. In vitro, the anti-α4β7 IgA isotype was found to have the highest affinity for the α4β7 heterodimer, and it significantly reduced HIV replication in retinoic acid-treated α4β7 CD4 human T cells. This α4β7-specific IgA also displayed a high avidity for human and mouse α4β7 lymphocytes in both mouse and human inflammatory colitis tissues. These new antibodies, and in particular those with mucosa-targeting isotypes such as IgA, could therefore be potential novel therapeutic tools for treating HIV and inflammatory bowel disease.

Antiretroviral drug therapy (ART) effectively suppresses replication of both the immunodeficiency viruses, human (HIV) and simian (SIV); however, virus rebounds soon after ART is withdrawn. SIV-infected monkeys were treated with a 90-day course of ART initiated at 5 weeks post infection followed at 9 weeks post infection by infusions of a primatized monoclonal antibody against the α 4 β 7 integrin administered every 3 weeks until week 32. These animals subsequently maintained low to undetectable viral loads and normal CD4 + T cell counts in plasma and gastrointestinal tissues for more than 9 months, even after all treatment was withdrawn. This combination therapy allows macaques to effectively control viremia and reconstitute their immune systems without a need for further therapy., (Copyright © 2016, American Association for the Advancement of Science.)

Although extraordinary progress has been made in the treatment and prevention of HIV infection, the AIDS pandemic continues to rage globally with 2.1 million infections and 1.6 million AIDS-related deaths reported in 2013. Until an effective vaccine is developed, new strategies for treatment and prevention are needed. Regarding the prevention of HIV infection, a major focus of prevention research in general and vaccine research in particular involves the interaction of the HIV-1 envelope protein gp120 with cell-surface receptors, with the hope that a greater understanding of these interactions will lead to the development of novel strategies aimed at preventing and even treating HIV-1 infection. Particular attention has been directed toward gaining a more precise understanding of the early events in transmission focusing on that critical window of time when HIV first establishes infection in the host. Here we describe some of the recent findings involving HIV-1 envelope interactions with cell surface receptors that are relevant to transmission and which may represent new opportunities to develop strategies to prevent HIV infection.

The humoral immune response after acute infection with HIV-1 is delayed and ineffective. The HIV-1 envelope protein gp120 binds to and signals through integrin α4β7 on T cells. We found that gp120 also bound to and signaled through α4β7 on naive B cells, which resulted in an abortive proliferative response. In primary B cells, signaling by gp120 through α4β7 resulted in increased expression of the immunosuppressive cytokine TGF-β1 and FcRL4, an inhibitory receptor expressed on B cells. Coculture of B cells with HIV-1-infected autologous CD4(+) T cells also increased the expression of FcRL4 by B cells. Our findings indicated that in addition to mediating chronic activation of the immune system, viral proteins contributed directly to HIV-1-associated B cell dysfunction. Our studies identify a mechanism whereby the virus may subvert the early HIV-1-specific humoral immune response.

Mucosal transmission of HIV is inefficient. The virus must breach physical barriers before it infects mucosal CD4+ T cells. Low-level viral replication occurs initially in mucosal CD4+ T cells, but within days high-level replication occurs in Peyer's patches, the gut lamina propria and mesenteric lymph nodes. Understanding the early events in HIV transmission may provide valuable information relevant to the development of an HIV vaccine. The viral quasispecies in a donor contracts through a genetic bottleneck in the recipient, such that, in low-risk settings, infection is frequently established by a single founder virus. Early-transmitting viruses in subtypes A and C mucosal transmission tend to encode gp120s with reduced numbers of N-linked glycosylation sites at specific positions throughout the V1-V4 domains, relative to typical chronically replicating isolates in the donor quasispecies. The transmission advantage gained by the absence of these N-linked glycosylation sites is unknown. Using primary α₄β₇/CD4+ T cells and a flow-cytometry based steady-state binding assay we show that the removal of transmission-associated N-linked glycosylation sites results in large increases in the specific reactivity of gp120 for integrin-α₄β₇. High-affinity for integrin α₄β₇, although not found in many gp120s, was observed in early-transmitting gp120s that we analyzed. Increased α₄β₇ affinity is mediated by sequences encoded in gp120 V1/V2. α₄β₇-reactivity was also influenced by N-linked glycosylation sites located in C3/V4. These results suggest that the genetic bottleneck that occurs after transmission may frequently involve a relative requirement for the productive infection of α₄β₇+/CD4+ T cells. Early-transmitting gp120s were further distinguished by their dependence on avidity-effects to interact with CD4, suggesting that these gp120s bear unusual structural features not present in many well-characterized gp120s derived from chronically replicating viruses. Understanding the structural features that characterize early-transmitting gp120s may aid in the design of an effective gp120-based subunit vaccine.

Both activated and resting CD4(+) T cells in mucosal tissues play important roles in the earliest phases of infection after sexual transmission of HIV-1, a process that is inefficient. HIV-1 gp120 binds to integrin alpha(4)beta(7) (alpha(4)beta(7)), the gut mucosal homing receptor. We find that alpha(4)beta(7)(high) CD4(+) T cells are more susceptible to productive infection than are alpha(4)beta(7)(low-neg) CD4(+) T cells in part because this cellular subset is enriched with metabolically active CD4(+) T cells. alpha(4)beta(7)(high) CD4(+) T cells are CCR5(high) and CXCR4(low); on these cells, alpha(4)beta(7) appears in a complex with CD4. The specific affinity of gp120 for alpha(4)beta(7) provides a mechanism for HIV-1 to target activated cells that are critical for efficient virus propagation and dissemination following sexual transmission.

We have identified two new histone deacetylase (HDAC) inhibitors (9 and 24) capable of inducing the expression of gamma-globin and/or beta-globin promoter-driven reporter genes in a synthetic model of Hb switch. Both compounds also increased, with different mechanisms, the gamma/(gamma+beta) ratio expressed in vitro by normal human erythroblasts. Compound 9 increased the levels of gamma-globin mRNA and the gamma/(gamma+beta) ratio (both by 2-fold). Compound 24 increased by 3-fold the level of gamma-globin and decreased by 2-fold that of beta-globin mRNA, increasing the gamma/(gamma+beta) ratio by 6-fold, and raising (by 50%) the cell HbF content. Both compounds raised the acetylation state of histone H4 in primary cells, an indication that their activity was mediated through HDAC inhibition. Compounds 9 and 24 were also tested as gamma/(gamma+beta) mRNA inducers in erythroblasts obtained from patients with beta(0) thalassemia. Progenitor cells from patients with beta(0) thalassemia generated in vitro morphologically normal proerythroblasts that, unlike normal cells, failed to mature in the presence of EPO and expressed low beta-globin levels but 10 times higher-than-normal levels of the alpha hemoglobin-stabilizing protein (AHSP) mRNA. Both compounds ameliorated the impaired in vitro maturation in beta(0) thalassemic erythroblasts, decreasing AHSP expression to normal levels. In the case of two patients (of five analyzed), the improved erythroblast maturation was associated with detectable increases in the gamma/(gamma+beta) mRNA ratio. The low toxicity exerted by compounds 9 and 24 in all of the assays investigated suggests that these new HDAC inhibitors should be considered for personalized therapy of selected patients with beta(0) thalassemia.

Objective: To characterize how interleukin-3 and erythropoietin regulate cell fate by modulating the expression of lineage-specific transcription factors., Methods: This study analyzed mRNA and protein levels, gene transcription rates, and mRNA and protein stabilities of erythroid-specific transcription factors in lineage-restricted cells derived from the 32D cell line cultured either in interleukin-3 or erythropoietin., Results: Erythroid 32D subclones expressed levels of Idl, Gata-2, and Scl comparable and levels of Eklf and Gata-1 higher than those expressed by myeloid subclones. While maintained in interleukin-3, erythroid cells remained immature despite their high expression of Gata-1, Gata-2, Scl, Eklf, and Idl. Switching the erythroid cells to erythropoietin induced cell maturation (within 48 hours) and reduced expression of Gata-2 and Idl (in 24 hours) but did not alter the expression of Gata-1. The effects of interleukin-3 were mostly mediated by increases in transcription rates (Scl and Gata-2), and that of erythropoietin was apparently due to increased mRNA and protein (Gata-1, Scl, and Eklf) stability. In particular, erythropoietin increased the stability of the processed and transcriptionally more active form of GATA-1 protein., Conclusions: These results suggest that interleukin-3 and erythropoietin cooperate to establish the lineage-specific transcription factor milieu of erythroid cells: interleukin-3 regulates mainly gene transcription and erythropoietin consistently increases mRNA and protein stability.