Lepton pair photoproduction in peripheral relativistic heavy-ion collisions

We study the lepton pair photoproduction in peripheral heavy-ion collisions based on the formalism in our previous work [Phys. Rev. D 104, 056011 (2021)]. We present the numerical results for the distributions of the transverse momentum, azimuthal angle and invariant mass for $e^{+}e^{-}$ and $\mu^{+}\mu^{-}$ pairs as functions of the impact parameter and other kinematic variables in Au+Au collisions. Our calculation incorporates the information on the transverse momentum and polarization of photons which is essential to describe the experimental data. We observe a broadening effect in the transverse momentum for lepton pairs with and without smear effects. We also observe a significant enhancement in the distribution of $\cos(2\varphi)$ for $\mu^{+}\mu^{-}$ pairs. Our results provide a baseline for future studies of other higher order corrections beyond Born approximation and medium effects in the lepton pair production.Comment: 19 pages, 10 figure

The History, Mechanism, and Clinical Application of Auricular Therapy in Traditional Chinese Medicine

Auricular therapy includes acupuncture, electroacupuncture, acupressure, lasering, cauterization, moxibustion, and bloodletting in the auricle. For 2500 years, people have employed auricular therapy for treating diseases, but the methods have been limited to bloodletting and cauterization. Only after 1957, the international scientific community became aware that the map of the ear resembles an inverted fetus, its introduction has led to auricular acupuncture (AA) becoming a more systemic approach, and, following the identification and standardization of more precise points, AA has been employed in clinical applications. The mechanisms of AA are considered to have a close relationship with the autonomic nervous system, the neuroendocrine system, neuroimmunological factors, neuroinflammation, and neural reflex, as well as antioxidation. Auricular therapy has been applied, for example, for pain relief, for the treatment of epilepsy, anxiety, and obesity, and for improving sleep quality. However, the mechanisms and evidence for auricular therapy warrant further study

Influenza Virus Infection in Travelers to Tropical and Subtropical Countries

Background. Influenza outbreaks have been reported among travelers, but attack rates and incidence are unknown. Methods. A cohort study was conducted. Travelers to subtropical and tropical countries recruited at the University of Zurich Travel Clinic (Switzerland), January 1998 to March 2000, were investigated with pre- and posttravel assessment of hemagglutination inhibition and by questionnaire. Results. Among 1450 travelers recruited who completed questionnaires and provided serum samples before departure, 289 (19.9%) reported febrile illness during or after traveling abroad; of these, 211 (73.0%) provided paired serum samples. Additionally, paired serum samples were collected from 321 frequency-matched afebrile control subjects among the remaining 1161 subjects of the study population. Seroconversion for influenza virus infection was demonstrated in 40 (2.8%) of all travelers; 18 participants (1.2%) had a ⩾4-fold increase in antibody titers. This corresponds to an incidence of 1.0 influenza-associated events per 100 person-months abroad. Among the 211 febrile participants, 27 (12.8%) had seroconversion, 13 (6.2%) with a ⩾4-fold increase; among the 321 afebrile control subjects, 13 (4.0%) had seroconversion, 5 (1.6%) with a ⩾4-fold increase. Twenty-five seroconverters (62.5%; P = .747) acquired influenza outside of the European epidemic season. Sixteen patients (40.0%) sought medical attention either abroad or at home, and 32 (80.0%) were asymptomatic at the time of completion of the survey. Conclusions. This survey indicates that influenza is the most frequent vaccine-preventable infection among travelers to subtropical and tropical countries. Infections occur mainly outside the domestic epidemic season, and they have a considerable impact. Pretravel vaccination should be considered for travelers to subtropical and tropical countrie

Omics approach for generating a high-yield CHO cell line producing monoclonal antibodies

Chinese hamster ovary (CHO) cells are extensively used for the industrial manufacture of therapeutic antibodies. Generating high producing cell lines for secretory protein production requires knowing the bottleneck in the cellular machinery for protein expression. Integration site of gene of interest (GOI) is one of the important factors that influence the protein productivity. Even though screening of cells randomly integrated GOI can select high producing cells, the selected cell might not stable due to the chromosome instability. Here, we would like to look for host integration sites where GOI is high yield and stable by screening a single copy integration system. We developed several methods to identify integration sites including PCR based, whole genome sequencing based, and a platform to integrate a single copy of GOI into host genome. By determining the integration sites of the high producing clones, we can elucidate the major high yield sites for target gene expression. We have also employed the genome-editing tool, TALEN and CRISPR/cas9 to specifically integrate the vector with an antibody gene into two integration sites of CHO genome. Our data showed, IS1 and IS2 integration sites can be actively edited and specifically integrated an antibody expression vector of 15kb by either TALEN or CRISPR/Cas9. We successfully established site specifically integrated cell pools and expanded the FACS-sorted single cell into a cell line. Each single cell derived cell lines was confirmed by junction-PCR and sequence analysis. Furthermore, these single cells derived CHO cell lines are shown to express antibody gene with high titer. With the combination of omics knowledge and toolbox, including CHO genomics, transcriptomics and CHO specific microarray, GOI can be stably and highly produced

Studies of the Binding Properties of Influenza Hemagglutinin Receptor-Site Mutants

AbstractSite-specific mutations have been made in the influenza hemagglutinin (HA) receptor binding site to assess the contribution of individual amino acid residues to receptor recognition. Screening of mutant HAs, expressed using recombinant vaccinia virus-infected cells, for their abilities to bind human erythrocytes indicated that substitutions involving conserved residues Y98F, H183F, and L194A severely restricted binding and that the substitution W153A prevented cell surface expression of HA. Mutation of residues E190 and S228 that are in positions to form hydrogen bonds with the 9-OH of sialic acid appeared to increase erythrocyte binding slightly, as did the substitution G225R. Substitutions of other residues that are directly or indirectly involved in receptor binding, S136T, S136A, Y195F, G225D, and L226P, had intermediate effects on binding between these two extremes. Estimates of changes in receptor binding specificity based on inhibition of binding to erythrocytes by nonimmune horse sera indicated that mutants G225R and L226P, unlike wild-type HA, were not inhibited; Y195F and G225D mutants were, like wild type, inhibited; and erythrocyte binding by mutants S136A, S136T, E190A, and S228G was only partially inhibited. Viruses containing mutant HAs Y98F, S136T, G225D, and S228G that cover the range of erythrocyte binding properties observed were also constructed by transfection. All four transfectant viruses replicated in MDCK cells and embryonated hens' eggs as efficiently as wild-type X-31 virus, although the Y98F mutant virus was unable to agglutinate erythrocytes. Mutant MDCK cells that have reduced levels of cell surface sialic acids were susceptible to infection by S136T, G225D, and S228G transfectant viruses and by wild type but not by the Y98F transfectant virus