Article Gate
Not a member yet
471 research outputs found
Sort by
Structural Diversity of Lithium Oligo-α-Pyridylamides
Lithium oligo-α-pyridylamides are useful intermediates in coordination chemistry. Upon trans-metalation they have afforded a variety of extended metal atom chains (EMACs), which are currently investigated as molecular wires and single-molecule magnets. However, structural information on this class of compounds is scarce. Two trilithium salts of a new, sterically encumbered oligo-α-pyridylamido ligand were isolated in crystalline form and structurally characterized in the solid state and in solution. Lithiation of N2-(trimethylsilyl)-N6-{6-[(trimethylsilyl)amino]pyridin-2-yl}pyridine-2,6-diamine (H3L) with n-BuLi in thf yielded dimeric adduct [Li6L2(thf)6] (1), which was crystallized from n-hexane/thf as 1·C6H14. Crystals of a tetra-thf solvate with formula [Li6L2(thf)4] (2) were also obtained. The compounds feature two twisted L3− ligands exhibiting a cis-cis conformation and whose five nitrogen donors are all engaged in metal coordination. The six Li+ ions per molecule display coordination numbers ranging from 3 to 5. Compound 1·C6H14 was investigated by multinuclear 1D and 2D NMR spectroscopy, including 1H DOSY experiments, which indicated retention of the dimeric structure in benzene-d6 solution. To the best of our knowledge, 1 and 2 are the longest-chain lithium oligo-α-pyridylamides structurally authenticated so far, thereby qualifying as appealing intermediates to access high-nuclearity EMACs by trans-metalatio
HPV Vaccination among Sexual and Gender Minority Youth Living with or at High-Risk for HIV
Background: Human papillomavirus (HPV) is epidemic among young people, especially those at highest risk of acquiring HPV-related cancers. Methods: Youth aged 14–24 years old (N = 1628) were recruited from 13 clinics, community agencies, and social media sites in Los Angeles, California, and New Orleans, Louisiana, that specialized in serving sexual and gender minority youths (SGMY), especially males at risk for HIV. A cross-sectional comparison of sociodemographic and risk histories of HPV vaccinated/unvaccinated youths was conducted using both univariate and multivariate regressions. Results: About half (51.9%) of youth were vaccinated, with similar percentages across states and across genders. Sexual and gender minority youths (SGMY, i.e., gay, bisexual, transgender, and non-heterosexual; 68.8%) and their heterosexual peers (15%) were equally likely to be vaccinated (54%), even though their risk for HPV-related cancers is very different. Vaccinations were higher among younger youth, those not using condoms, youth with greater education, that possessed a primary health care provider, and youth diagnosed with HIV. Vaccinations were lower among youth that were out-of-home due to mental health inpatient hospitalization, drug treatment, homelessness, or incarceration. Conclusions: Special programs are required to target youth experiencing multiple life stressors, especially out-of-home experiences, those with less education, and without the safety net of health insurance or a provider
COVID-19 Vaccine Acceptance Rate and Its Factors among Healthcare Students: A Systematic Review with Meta-Analysis
Healthcare students are clinicians-in-training likely to come into contact with COVID-19 as much as other frontline healthcare professionals. It is therefore necessary to prioritize vaccinations for this group. We conducted a global systematic assessment of COVID-19 vaccine acceptance rates and related factors among healthcare students using the PubMed, Scopus, and Web of Science databases and keyword searches in March of 2022. We found 1779 articles with relevant information and 31 articles that matched our inclusion criteria. We performed a random-effects meta-analysis and quality assessment using the eight-item Joanna Briggs Institute Critical Appraisal test for cross-sectional studies. A total of 30,272 individuals from 16 countries were studied. Most of the studies were carried out in the U.S. (n = 6), China (n = 5), Poland (n = 5), India (n = 2), Italy (n = 2), and Israel (n = 2). The prevalence of the COVID-19 vaccine acceptance rate was 68.8% (95% confidence interval [CI]: 60.8–76.3, I2 = 100%), and the prevalence of the vaccine hesitancy rate was 25.8% (95% CI: 18.5–33.8, I2 = 99%). In country-specific analyses, Romania showed the highest acceptance rate (88.0%, 95% CI: 44.5–100%), while Iraq showed the lowest acceptance rate (66.2%, 95% CI: 35.5–90.8%). In time-trend analyses, we found that acceptance rates among healthcare students decreased over time. Students concerned about potentially serious side effects of the vaccine were less willing to accept the vaccine. National and international interventions should be adopted to reduce COVID-19 vaccination hesitancy rates among these important frontline workers
Epitope Profiling of Diphtheria Toxoid Provides Enhanced Monitoring for Consistency Testing during Manufacturing Process Changes
In the vaccine industry, multiple physicochemical, immunological, in vitro and in vivo analytical methods are applied throughout the manufacturing process to characterize and monitor the quality of vaccines. Presented here is the Single Epitope Antigenicity Test (SEAT), an innovative, quantitative epitope profiling method which provides an extended immunochemical analysis for diphtheria toxoid (DTxd) to be used for consistency testing during manufacturing process changes. The method uses BioLayer Interferometry (BLI) and a panel of monoclonal antibodies (mAbs) to independently assess nine individual antigenic sites of DTxd. The panel includes mAbs which are functional, bind distinct sites on DTxd and are able to distinguish intact DTxd from that which has been exposed to heat treatment. The SEAT method was qualified for precision, accuracy, and linearity, and was used to define a preliminary comparability range for DTxd made using the current manufacturing process. DTxd lots manufactured using alternate processes were assessed in the context of this range to determine the impact on DTxd antigenicity. Epitope profiling by SEAT provides quantitative information on the integrity of multiple important antigenic regions of DTxd, and therefore represents a valuable tool in a comprehensive analytical test package which can be used to support manufacturing process changes for vaccine
Effects of Exercise and Physical Activity Levels on Vaccination Efficacy: A Systematic Review and Meta-Analysis
Objective: We examined whether different intensities of exercise and/or physical activity (PA) levels affected and/or associated with vaccination efficacy. Methods: A systematic review and meta-analysis was conducted and registered with PROSPERO (CRD42021230108). The PubMed, EMBASE, Cochrane Library (trials), SportDiscus, and CINAHL databases were searched up to January 2022. Results: In total, 38 eligible studies were included. Chronic exercise increased influenza antibodies (standardized mean difference (SMD) = 0.49, confidence interval (CI) = 0.25–0.73, Z = 3.95, I2 = 90%, p 0.05). PA levels positively affected antibodies in response to influenza vaccination (SMD = 0.18, CI = 0.02–0.34, Z = 2.21, I2 = 76%, p = 0.03), which was mainly driven by high PA levels compared to moderate PA levels (Chi2 = 10.35, I2 = 90.3%, p 4 weeks (SMD = 0.64, CI = 0.30–0.98, Z = 3.72, I2 = 83%, p 0.05; Chi2 = 13.40, I2 = 92.5%, p < 0.01) post vaccination. Conclusion: Chronic aerobic exercise or high PA levels increased influenza antibodies in humans more than vaccinated individuals with no participation in exercise/PA. The evidence regarding the effects of exercise/PA levels on antibodies in response to vaccines other than influenza is extremely limite
Awareness of Being at Risk of Stroke and Its Determinant Factors among Hypertensive Patients in Banyumas, Indonesia
Background. The global burden of stroke is still high, particularly in developing countries, with hypertension serving as the main risk factor. The awareness of stroke among hypertensive patients is crucial for stroke prevention. This study was aimed at identifying the awareness of being at risk of stroke and its determinant factors among hypertensive patients in Banyumas, Indonesia. Methods. This was a cross-sectional study conducted in Primary Health Centers (PHCs) in Banyumas Regency, Indonesia, from April to August 2019. A simple random sampling technique was used to select the representatives’ PHCs. Hypertensive patients who came regularly to the PHCs were consecutively recruited. Data were collected through a self-reported questionnaire and medical records. The main outcome was the level of participants’ awareness of being at risk of stroke. Multivariate logistic regression analysis was performed to measure determinant factors associated with the level of awareness. Results. Out of 457 patients investigated, 77.46% had a low level of awareness. Low knowledge of hypertension, low income, and no history of previous stroke were associated with a low-level of awareness (odds ratio (OR) 1.942, 95% CI 1.195-3.158, 0.007; OR 2.321, 95% CI 1.326-4.064, 0.003; and OR 6.033, 95% CI 2.450-14.858, , respectively). Conclusion. Majority of hypertensive patients were unaware of being at risk of stroke. Knowledge of hypertension, income, and history of previous stroke are factors that may influence the awareness of being at risk of stroke among them. This emphasizes the need to provide better campaigns and education programs to raise the awareness of stroke in a community setting, particularly for the population at risk
Cog Threads for Transvaginal Prolapse Repair: Ex-Vivo Studies of a Novel Concept
The diagnosis and treatment of pelvic organ prolapse (POP) remain a relevant and scientifically challenging topic. The number of cases of genital prolapse increases each year, one in ten women need at least one surgical procedure and one in four women in midlife have asymptomatic prolapse. Using mesh implants to correct POP presents unsatisfactory clinical outcomes, requiring hospital readmission and further surgery. We hypothesize using an alternative surgical intervention technique, applying injectable biodegradable cog threads, currently used for face lifting procedures, to reinforce and correct vaginal wall defects. The threads used in this investigation are commercially available 360° 4D barb threads (PCL-19G-100), made of polycaprolactone (PCL), supplied in sterile packs (Yastrid, Shanghai, China). Eleven sows’ vaginal walls were used to analyze the immediate reinforcement effect of the threads. Uniaxial tensile testing and scanning electron microscopy (SEM) was performed for the initial characterization of the threads. Threads were inserted into the vaginal wall (control n = 5, cog n = 5) and were characterized by ball burst testing; a pull-out test was performed (n = 6). With SEM images, dimensions, such as thread diameter (≈630 µm), cut angle (≈135°), cut depth (≈200 µm) and cog distance (≈1600 µm) were measured. The mechanical behavior during uniaxial tensile testing was nonlinear. Threads could sustain 17–18 N at 18–22% of deformation. During the ball burst test, vaginal tissue reinforced with threads could support 68 N more load than normal tissue (p < 0.05), indicating its strengthening effect. Comfort and stress zones were significantly stiffer in the tissues reinforced with threads (p < 0.05; p < 0.05). Both groups showed identical deformation (elongation); no significant differences in the comfort zone length were observed, showing that threads do not affect tissue compliance. The pull-out test showed that the threads could sustain 3.827 ± 0.1891 N force when the first cog slip occurs, at 11.93 ± 0.8291 mm. This preliminary research on using PCL cog threads for POP treatment showed promising results in increased vaginal wall resistance to pressure load and, at the same time, not affecting its compliance. Nevertheless, to obtain long term host response in vivo, further investigation will be carried out
Age-Dependent Dynamics of Maternally Derived Antibodies (MDAs) and Understanding MDA-Mediated Immune Tolerance in Foot-and-Mouth Disease-Vaccinated Pigs
Vaccine-induced active immunity in young animals may be compromised via interference caused by maternally derived antibodies (MDAs). Since the level, titer, and half-life of MDAs vary per individual, it is difficult to determine the appropriate timing of foot-and-mouth disease (FMD) vaccination in the field. In order to better understand the age-dependent characteristics of MDA in sows and piglets as well as the phenomenon of reduced vaccine-mediated active immunity due to MDAs, this study sought to determine antibody titers through structural protein (SP) O, A ELISA analyses, and virus-neutralizing (VN) antibody titers as well as their half-lives in the sera of sows and piglets derived from FMD-vaccinated mother. Furthermore, immunoglobulin (Ig) subtypes, such as IgG, IgM, and IgA, in serum were also evaluated. To understand the correlation between the inhibition of vaccine-mediated active immunity by MDA-mediated passive immunity and regulatory T (Treg) cells, Treg-related cytokine levels were explored. Our findings will help to predict the optimal timing of vaccination for overcoming MDAs and inducing a robust vaccine-mediated immune response in young individuals vaccinated against FMD. They also add to our understanding of MDA characteristics and interference, providing insight for the development of innovative strategies and novel FMD vaccine for overcoming such interference
Acceptance or Rejection of the COVID-19 Vaccine: A Study on Iranian People’s Opinions toward the COVID-19 Vaccine
We aimed to assess the Iranian people’s attitude and confidence in the COVID-19 vaccine, their concerns about the safety of vaccines, and their reasons for accepting or rejecting the COVID-19 vaccine. We conducted a web-based cross-sectional study with a mixed qualitative–quantitative approach from December 2020 to February 2021. Our questionnaire consisted of a COVID-19 vaccine attitude questionnaire, a COVID-19 vaccine confidence inventory, a modified vaccine safety scale, and questions about participants’ decision to accept or refuse the COVID-19 vaccine, and their explanations for their decisions. The research included 1928 people with an average age of 34.88 years with 1236 (64.1%) being female. A total of 1330 participants desired to have the COVID-19 vaccine (69%). Female gender, lower educational levels, following COVID-19 news through sources other than websites and social media, not following COVID-19 news, and loss of a first-degree relative due to COVID-19 were all associated with a more negative attitude toward the COVID-19 vaccine (p < 0.01). To conclude, the acceptance rate of the COVID-19 vaccine among Iranians is comparable to the international average; however, it is still unfavorable. There are serious challenges to the vaccination program in Iran, such as older adults’ lower intention to undergo the COVID-19 vaccine and misinformatio
Immunological Cross-Protection between Different Rabbit Hemorrhagic Disease Viruses—Implications for Rabbit Biocontrol and Vaccine Development
The use of rabbit hemorrhagic disease virus (RHDV) as a biocontrol agent to control feral rabbit populations in Australia, in combination with circulating endemic strains, provides a unique environment to observe the interactions between different lagoviruses competing for the same host. Following the arrival of RHDV2 (GI.2) in Australia, it became necessary to investigate the potential for immunological cross-protection between different variants, and the implications of this for biocontrol programs and vaccine development. Laboratory rabbits of various immune status—(1) rabbits with no detectable immunity against RHDV; (2) rabbits with experimentally acquired immunity after laboratory challenge; (3) rabbits immunised with a GI.2-specific or a multivalent RHDV inactivated virus prototype vaccine; or (4) rabbits with naturally acquired immunity—were challenged with one of three different RHDV variants (GI.1c, GI.1a or GI.2). The degree of cross-protection observed in immune rabbits was associated with the variant used for challenge, infectious dose of the virus and age, or time since acquisition of the immunity, at challenge. The immune status of feral rabbit populations should be determined prior to intentional RHDV release because of the high survival proportions in rabbits with pre-existing immunity. In addition, to protect domestic rabbits in Australia, a multivalent RHDV vaccine should be considered because of the limited cross-protection observed in rabbits given monovalent vaccines