Physically unclonable security patterns created by electrospinning, and authenticated by two-step validation method.

Counterfeiting is a growing economic and social problem. For anticounterfeiting, random and inimitable droplet/fiber patterns were created by the electrospinning method as security tags that are detectable under UV light but invisible in daylight. To check the authenticity of the original security patterns created; images were collected with a simple smartphone microscope and a database of the recorded original patterns was created. The originality of the random patterns was checked by comparing them with the patterns recorded in the database. In addition, the spectral signature of the patterns in the droplet/fiber network was obtained with a simple and hand-held spectrometer. Thus, by reading the spectral signature from the pattern, the spectral information of the photoluminescent nanoparticles was verified and thus a second-step verification was established. In this way, anticounterfeiting technology that combines ink formula, unclonable security pattern creation and two-level verification is developed.

The understanding of the immunopathology in COVID-19 infection.

Coronaviruses belonging to the Coronaviridae family are single-stranded RNA viruses. The entry of SARS-CoV-2 is accomplished via ACE-2 receptors. SARS-CoV-2 infection coactivates both innate and adaptive immune responses. Although SARS-CoV-2 stimulates antibody production with a typical pattern of IgM/IgG, cellular immunity is also impaired. In severe cases, low CD4 + and CD8 + T cell counts are associated with impaired immune functions, and high neutrophil/lymphocyte ratios accompanying low lymphocyte subsets have been demonstrated. Recently, high IFN -α/γ ratios with impaired T cell responses, and increased IL-1, IL-6, TNF-α, MCP-1, IP-10, IL-4, IL-10 have been reported in COVID-19 infection. Increased proinflammatory cytokines and chemokines in patients with severe COVID-19 may cause the suppression of CD4 + and CD8 + T cells and regulatory T cells, causing excessive inflammatory responses and fatal cytokine storm with tissue and organ damage. Consequently, novel therapeutics to be developed against host immune system, including blockade of cytokines (IL-6, IL-1, IFN) themselves, their receptors or signaling pathways- JAK inhibitors- could be effective as potential therapeutics.

Low skeletal muscle mass index is associated with function and nutritional status in residents in a Turkish nursing home.

INTRODUCTION: To determine the prevalence of low muscle mass (LMM) and the relationship between LMM with functional and nutritional status as defined using the LMM evaluation method of European Working Group on Sarcopenia in Older People (EWGSOP) criteria among male residents in a nursing home. METHODS: Male residents aged >60 years of a nursing home located in Turkey were included in our study. Their body mass index (BMI) kg/m2, skeletal muscle mass (SMM-kg) and skeletal muscle mass index (SMMI-kg/m2) were calculated. The participants were regarded as having low SMMI if they had SMMI <9.2 kg/m2 according to our population specific cut-off point. Functional status was evaluated with Katz activities of daily living (ADL) and Lawton Instrumental Activities of Daily Living (IADL). Nutritional assessment was performed using the Mini Nutritional Assessment (MNA). The number of drugs taken and chronic diseases were recorded. RESULTS: One hundred fifty-seven male residents were enrolled into the study. Their mean age was 73.1 ± 6.7 years with mean ADL score of 8.9 ± 2.0 and IADL score of 8.7 ± 4.6. One hundred twelve (71%) residents were aged >70 years. Thirty-five men (23%) had low SMMI in group aged >60 years, and twenty-eight subjects (25%) in the group aged >70 years. MNA scores were significantly lower in residents with low SMMI compared with having normal SMMI (17.1 ± 3.4 versus 19.6 ± 2.5, p = 0.005). BMI was significantly lower in the residents with low SMMI compared with normal SMMI (19.6 ± 2.7 versus 27.1 ± 4.1, p< 0.001). ADL scores were significantly different between residents with low SMMI and normal SMMI in those aged >70 years (8.1 ± 2.6 versus 9.1 ± 1.6, p = 0.014). In regression analyses, the only factor associated with better functional status was the lower age (p = 0.04) while the only factor associated with better nutrition was higher SMMI (p = 0.01). CONCLUSIONS: Low SMMI detected by LMM evaluation method of EWGSOP criteria is prevalent among male nursing home residents. There is association of low SMMI with nutritional status and probably with functional status within the nursing home setting using the EWGSOP criteria with Turkish normative reference cut-off value.

Case report of fatal Mycobacterium tilburgii infection.

There are few reports concerning Mycobacterium tilburgii infection in humans because this bacterium is non-cultivatable. Herein, using new molecular techniques, we report the case of an immunocompromised patient with fatal disseminated lymphadenitis that was caused by M. tilburgii.26 years old Caucasian HIV negative female patient presented with abdominal pain. Her clinical assessment revealed disseminated lymphadenitis, that was acid fast bacilli positive. Further molecular evaluation showed the causative agent as M. tilburgii. Despite anti mycobacterial therapy and careful management of intervening complications patient died because of an intraabdominal sepsis. This is the first fatal M. tilburgii infection in the literature. This case points the importance of careful management of patient's immune status and intervening infections besides implementation of effective drug treatment.

Antibody Response to COVID-19 Vaccines in Healthcare Workers: Which One is More Successful? Homologous or Heterologous?

Objectives: We aimed to determine the antibody levels created by COVID-19 vaccination in healthcare workers and the factors affecting the antibody response. Methods: Our research is a single-center, observational study that was prospectively designed and retrospectively analyzed at the beginning of the COVID-19 pandemic, and included 103 healthcare workers who received the three-dose regimen of COVID-19 vaccine. In accordance with the recommendations of the Ministry of Health of Turkey, the first two doses of CoronaVac vaccine were administered routinely, while the booster dose was given as BioNTech or CoronaVac (heterologous or homologous vaccination) depending on the preference of the volunteers. Antibody titers against the SARS-CoV-2 were measured in all individuals at different time points (1 month after the second dose of CoronaVac, before the booster dose [BioNTech or CoronaVac] at the fifth month and one month after the booster dose) with AESKULISA® SARS-CoV-2 S1 IgG (AESKU DIAGNOSTICS, Wendelsheim, Germany). Results: The mean age was 39.98±11.31 years, 62.1% of whom were women and 54.4% of them were accompanied by comorbid disease. After two doses of CoronaVac, the antibody titer averaged 49.50±33.15 U/mL in the 1st month (antibody seropositivity 86%) and the antibody titer decreased 24.01±33.48 U/mL (antibody seropositivity 49.5%) at 5th month. The mean antibody titer was found 59.73±60.20 U/ml in those who received the booster dose of homologous and 185.07±46.28 U/mL in those who were heterologous (p<0.001). Antibody levels were detected significantly lower after the booster dose of vaccination in patients with comorbidities (p<0.05). Conclusion: Our study, which reflects the data within the scope of the Turkey Ministry of Health's COVID-19 vaccination program determined that the antibody response after heterologous vaccination is better than in homologous vaccination. Antibody titer level in the 5th month was 50% waned after two doses of inactivated vaccination. It was also shown that factors such as gender, age, body mass index, and smoking did not create a statistically significant difference in homologous and heterologous vaccination, but after the booster dose antibody levels decreased significantly in those with comorbidity.

Optimization and performance of nitrogen-doped carbon dots as a color conversion layer for white-LED applications.

In this study, green-emitting nitrogen-doped carbon dots (N-CDots) were synthesized and incorporated into drop-cast composite films for use as color conversion layers in a white-LED configuration to generate white light. In order to resolve the red deficiency of this configuration, a commercial red phosphor was integrated into the system. Moreover, the N-CDots were also processed into polymer/N-CDot composite fibers, for which we determined the amount of N-CDots that yielded adequate white-light properties. Finally, we showed that white light with excellent properties could be generated by employing both of the fabricated N-CDot composites either as drop-cast films or composite fibers. Hence, N-CDots provide a promising alternative to inorganic phosphors that are commonly employed in white-LED configurations.

Humidity sensing properties of ZnO-based fibers by electrospinning.

Zinc oxide (ZnO) based fibers with a diameter of 80-100 nm were prepared by electrospinning. Polyvinyl alcohol (PVA) and zinc acetate dihydrate were dissolved in water and the polymer/salt solution was electrospun at 2.5 kV cm(-1). The resulting electrospun fibers were subjected to calcination at 500°C for 2h to obtain ZnO-based fibers. Humidity sensing properties of the fiber mats were investigated by quartz crystal microbalance (QCM) method and electrical measurements. The adsorption kinetics under constant relative humidity (RH) between 10% and 90% were explained using Langmuir adsorption model. Results of the measurements showed that ZnO-based fibers were found to be promising candidate for humidity sensing applications at room temperature.