44 research outputs found
Submandibular glands in the metabolic syndrome
In addition to their stimulatory action on neuronal differentiation and survival, a variety of neurotrophic factors, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor, exert metabotrophic effects, including improvement of glucose, lipid and energy homeostasis. It was recently reported that plasma levels of both NGF and BDNF are reduced in patients with advanced metabolic syndrome and with acute coronary syndromes, and that NGF tissue content is decreased in human atherosclerotic coronary arteries. Since NGF and BDNF are synthesized, stored, and released by submandibular salivary glands, we investigated the structure and function of these glands. Here we present our scintigraphic and echographic results of submandibular glands of patients with advanced stage of metabolic syndrome: (i) scintigraphic analysis using the radiotracer (99m)Tc-pertechnetate showed an inhibition of salivary gland excretory activity, and (ii) echographic evaluation revealed a parenchymal destruction and a prominent fibrosis of the glands. Both suggestive for the involvement of submandibular glands in decreased secretion of NGF and BDNF as implicated in the pathogenesis of metabolic syndrome.Biomedical Reviews 2007; 18: 65-67
Signal transduction in a covalent post-assembly modification cascade
Natural reaction cascades control the movement of biomolecules between cellular compartments. Inspired by these systems, we report a synthetic reaction cascade employing post-assembly modification reactions to direct the partitioning of supramolecular complexes between phases. The system is composed of a self-assembled tetrazine-edged FeII8L12 cube and a maleimide-functionalized FeII4L6 tetrahedron. Norbornadiene (NBD) functions as the stimulus that triggers the cascade, beginning with the inverse-electron-demand Diels–Alder reaction of NBD with the tetrazine moieties of the cube. This reaction generates cyclopentadiene as a transient by-product, acting as a relay signal that subsequently undergoes a Diels–Alder reaction with the maleimide-functionalized tetrahedron. Cyclooctyne can selectively inhibit the cascade by outcompeting NBD as the initial trigger. Initiating the cascade with 2-octadecyl NBD leads to selective alkylation of the tetrahedron upon cascade completion. The increased lipophilicity of the C18-tagged tetrahedron drives this complex into a non-polar phase, allowing its isolation from the initially inseparable mixture of complexes
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
How has Covid-19 affected the Global Value Chains? A dive into the development of academic literature
Seroprevalence of anti-HAV total antibodies among workers in wastewater treatment plants
Objectives
Data on high frequency of hepatitis A virus (HAV) antibodies for wastewater treatment staff is contradictory. Literature lacks data on the seroprevalence of antibodies to HAV (anti-HAV) among workers in wastewater treatment plants (WWTPs) in Bulgaria. The aim of this study is to establish a specific humoral immune response to hepatitis A virus – anti-HAV total antibodies among staff in WWTPs.
Material and Methods
A complex study of health and working conditions included 110 subjects working in 3 WWTPs in Bulgaria (74% of all workers in the 3 studied WWTPs and 20% of all employees in Bulgaria registered in 2014 under the wastewater collection, discharge and treatment code of economic activity). Workers had been differentiated in 3 groups on the basis of their occupational work: operators, support staff and other workers exposed to biological agents. Venous blood from all 110 subjects was tested once for carriers of HAV antibodies.
Results
Anti-HAV total antibodies were found for 52.7% of workers in WWTPs. There is a positive association between activity performed in WWTPs (operators, maintenance personnel and others exposed) and a positive one for the presence of anti-HAV (Chi 2 = 6.882, df = 2, p = 0.032). Odds ratio (OR) for hepatitis A increases 2.9 times in the group of operators vs. others exposed to biological agents in WWTPs (OR = 2.914, 95% confidence interval (CI): 1.149–7.393, Fisher’s p = 0.039). Odds ratio for hepatitis A increases 4.3 times in the group of support staff from WWTPs vs. others exposed to biological agents in WWTP (OR = 4.295, 95% CI: 1.075–17.167, Fisher’s p = 0.049).
Conclusions
Higher frequency of anti-HAV antibodies among operators and maintenance personnel at WWTPs has been established as compared to other workers exposed to biological agents in WWTPs. There is a positive association between increasing age of the workers and the presence of anti-HAV. Int J Occup Med Environ Health 2018;31(3):307–31
Molecular pathogenesis of spontaneous abortions - Whole genome copy number analysis and expression of angiogenic factors.
OBJECTIVE
To study two major molecular alterations in spontaneous abortions (SA) with unexplained etiology - fetal genomic anomalies and the endometrial expression of main angiogenic factors VEGFA/VEGFR2 and chemokines SDF-1/CXCR4.
MATERIALS AND METHODS
Whole genome copy number analysis by arrayCGH or Next Generation Sequencing (NGS) was applied for detection of fetal genomic imbalances. The abortive decidua of SA without fetal aneuploidies was further investigated for expression levels of the abovementioned factors using real time PCR analysis. A total of 30 abortive materials were collected from spontaneous abortions after exclusion of known predisposing factors.
RESULTS
In 21 of 30 spontaneous abortions (70%), genomic anomalies were discovered by whole genome copy number analysis. Numerical anomalies were detected in 90% of aberrant cases, and in 10% - structural aberrations were revealed. An increased expression for essential factors of angiogenesis was identified in spontaneous abortions' tissues - 3.44 times for VEGFA and 10.29 times for VEGFR2. We found an average of 14 times increase in the expression levels of SDF-1 and 3.21 times for its receptor CXCR4.
CONCLUSION
We could suggest the occurrence of increased angiogenesis in SA without fetal aneuploidies, compared to the control tissues, which could lead to increased oxidative stress and fetal loss
Ciprofloxacin-Loaded Mixed Polymeric Micelles as Antibiofilm Agents
In this work, mixed polymeric micelles (MPMs) based on a cationic poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA29-b-PCL70-b-PDMAEMA29) and a non-ionic poly(ethylene oxide)–b-poly(propylene oxide)–b-poly(ethylene oxide) (PEO99-b-PPO67-b-PEO99) triblock copolymers, blended at different molar ratios, were developed. The key physicochemical parameters of MPMs, including size, size distribution, and critical micellar concentration (CMC), were evaluated. The resulting MPMs are nanoscopic with a hydrodynamic diameter of around 35 nm, and the ζ-potential and CMC values strongly depend on the MPM’s composition. Ciprofloxacin (CF) was solubilized by the micelles via hydrophobic interaction with the micellar core and electrostatic interaction between the polycationic blocks, and the drug localized it, to some extent, in the micellar corona. The effect of a polymer-to-drug mass ratio on the drug-loading content (DLC) and encapsulation efficiency (EE) of MPMs was assessed. MPMs prepared at a polymer-to-drug mass ratio of 10:1 exhibited very high EE and a prolonged release profile. All micellar systems demonstrated their capability to detach pre-formed Gram-positive and Gram-negative bacterial biofilms and significantly reduced their biomass. The metabolic activity of the biofilm was strongly suppressed by the CF-loaded MPMs indicating the successful drug delivery and release. The cytotoxicity of empty and CF-loaded MPMs was evaluated. The test reveals composition-dependent cell viability without cell destruction or morphological signs of cell death
Transcatheter aortic valve implantation via transaortic surgical access
Представяме случай на 80-годишна пациентка със симптоматична високостепенна аортна стеноза и известна исхемична болест на сърцето, по повод на която е проведена предходна кардиохирургична реваскуларизация. Пациентката е високорискова за конвенционално кардиохирургично аортно клапно протезиране (SAVR) предвид наличната коморбидност и напредналата ѝ възраст, поради което при нея се предприе стратегия за транскатетърна аортна клапна имплантация (TAVI). Наличната подлежаща генерализирана атеросклероза създаде трудности при избора на подходящ съдов достъп за процедурата. При пациентката се използва трансаортен достъп, който бе техническо предизвикателство, с оглед запазването целостта на функциониращия аортокоронарен байпас при повторната стернотомия. Този клиничен случай демонстрира, че липсата на подходящ трансфеморален достъп за транскатетърно аортно клапно протезиране сам по себе си не е противопоказание за извършване на процедурата, а напротив трябва да служи като стимул за търсене и използване на нови и алтернативни съдови достъпи. We report a case of an 80-years–old patient with a severe, symptomatic aortic valve stenosis and history of ischemic heart disease, previously treated by coronary artery bypass graft surgery. The patient was contraindicated for conventional surgical aortic valve replacement (SAVR) due to advanced age and underlying comorbidity, therefore transcatheter aortic valve implantation (TAVI) has been offered. The access options for the procedure were restricted by the underlying generalized atherosclerosis process causing peripheral vessel disease. We have chosen transaortic access for the patient which in that case was the only possible option. The transaortic valve implantation was successful with satisfactory hemodynamic results, improvement in functional class heart failure of the patient and preserving the function and anatomy of the coronary artery bypass graft. This case report demonstrates that the lack of favorable transfemoral access for TAVI should not be a limitation by itself for the procedure, rather than be stimulus for searching and using new and alternative access for it