Comparison of a novel antigen detection test with reverse transcription polymerase chain reaction assay for laboratory diagnosis of SARS-CoV-2 infection.

Molecular diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by real-time reverse transcription polymerase chain reaction (RT-PCR) in respiratory specimens is considered the gold standard method. This method is highly sensitive and specific but it has some limitations such as being expensive and requiring special laboratory equipment and skilled personnel. RapidFor™ Antigen Rapid Test Kit is a commercially available Ag-RDT which is produced in Turkey and designed to detect the nucleocapsid antigen of SARS-CoV-2 in nasopharyngeal swab samples. The aim of this study was to evaluate the performance of this novel SARS-CoV-2 antigen detection considering the RT-PCR method as the gold standard. Four hundred forty-four nasopharyngeal swab samples which were collected from the patients who met clinical criteria of COVID-19 from ten centers in Turkey between September 2020 and February 2021 were included in the study. All the nasopharyngeal swab samples were tested for SARS-CoV-2 RNA using commercial RT-PCR kits (Bioeksen and A1 Lifesciences, Istanbul, Turkey) according to the manufacturer's instructions. Viral loads were assessed according to the cycle threshold (Ct) values. RapidFor™ SARS-CoV-2 antigen test (Vitrosens Biotechnology, Istanbul, Turkey) was used to investigate the presence of SARS-CoV-2 antigen in all samples following the manufacturer's instructions. Out of 444 nasopharyngeal swab samples tested, 346 (77.9%) were positive and 98 (22.1%) were negative for SARS-CoV-2 RNA by RTPCR. Overall sensitivity of the RapidFor™. Antigen Rapid Test Kit was 80.3% whereas specificity was found to be 87.8%. Positivity rate of rapid antigen test in samples with Ct values over 25 and below 30 was 82.7%, while it increased to 95.7% in samples 20 ≤ Ct < 25 and reached 100% in samples with Ct values below 20. RapidFor™ SARS-CoV-2 Ag test might be a good choice in the screening of symptomatic and asymptomatic patients and their contacts for taking isolation measures early, with advantages over RT-PCR as being rapid, easy and being applicable in every laboratory and even at point of care.

Association between vitamin D receptor gene FokI polymorphism and mortality in patients with sepsis.

BACKGROUND: Sepsis is life-threatening organ dysfunction as a result of the host's dysregulated immune response to infection. The vitamin D receptor (VDR) gene FokI polymorphism influences immune cell behavior. In the present study, we aimed to investigate the association between VDR FokI polymorphism and mortality in sepsis and non-sepsis patients in the intensive care unit (ICU). METHODS AND RESULTS: This is a prospective observational study involving 96 sepsis and 96 non-sepsis patients admitted to the Ege University ICU. VDR FokI polymorphisms were investigated, as well as the relationship between the identified polymorphisms and mortality.  In-hospital mortality was 27.1% in the sepsis group and 8.33% in the non-sepsis group (p = 0.001). The frequencies of VDR FokI TT, TC, and CC genotypes were 8 (8.33%), 48 (50.0%), and 40 (41.7%) in the sepsis group, and 11 (11.5%), 42 (43.8%), and 43 (44.8%) in the non-sepsis group, respectively (p = 0.612). In the sepsis group, the frequencies of Fokl TT, TC, and CC genotypes did not differ significantly between survivors and non-survivors. However, homozygous C allele carriers had lower overall mortality (p = 0.047). CONCLUSION: The VDR FokI polymorphism, particularly the CC genotype, appears to be associated with lower mortality in ICU patients.

Surface microbiota and associated staphylococci of houseflies (Musca domestica) collected from different environmental sources.

Houseflies (Musca domestica) are important mechanical vectors for the transmission of pathogenic microorganisms. In this study, 129 houseflies (69 males and 60 females) were collected from 10 different environmental sources and a laboratory population was used. The surface microbiota of houseflies was identified by Next-Generation Sequencing. Staphylococci from the surfaces of houseflies were selectively isolated and their virulence genes, antibiotic susceptibilities, biofilm formation, and clonal relatedness were determined. Metagenomic analysis results demonstrated that Staphylococcus, Bacillus, and Enterococcus were mostly present on the surface of houseflies at the genus level. Additionally, the isolated 32 staphylococcal strains were identified as Staphylococcus sciuri (n = 11), S. saprophyticus (n = 9), S. arlettae (n = 6), S. xylosus (n = 4), S. epidermidis (n = 1) and S. gallinarum (n = 1). tetK, tetM, tetL, ermC, msrAB, and aad6 genes were found to carry by some of the staphylococcal strains. The strains were mostly resistant to oxacillin, penicillin, and erythromycin and three strains were multi-drug resistant. There was a statistical difference between housefly collection places and antibiotic resistance of isolated staphylococci to penicillin G, gentamicin, and erythromycin (p < 0.05). Biofilm test showed that 17 strains were strong biofilm formers, and it plays important role in the transmission of these bacteria on the surface of houseflies. Staphylococcal strains showed extracellular proteolytic and lipolytic activity in 31 and 12 strains, respectively. Closely related species were found in PFGE analysis from different environmental sources. By this study, surface microbiota and carriage of pathogenic staphylococci on the surfaces of houseflies and their virulence properties were elucidated.

Diagnostic Accuracy of Early Systolic Notching in Pulmonary Embolism.

OBJECTIVE: Recently, a cardiac sonography finding, early systolic notching (ESN), was reported with high sensitivity and specificity for the diagnosis of pulmonary embolism (PE) in a limited population. The aim of this study was to determine the diagnostic accuracy of ESN finding for PE in emergency department (ED) patients. METHOD: This prospective multicenter study was conducted in 4 academic EDs. All patients who underwent computed tomography angiography for suspected PE were included in the study. After inclusion, cardiac ultrasound including the right ventricular outflow tract Doppler signal was performed. The diagnostic tests of ESN finding were used for PE and its subgroups. RESULTS: In the study, 183 of 201 patients met the study criteria. Of all patients, 52.5% had PE (n = 96), and 19.7% (n = 36) had ESN finding. In all ED patients, the sensitivity of ESN for PE was 34% (95% CI 25-45), and the specificity was 97% (95% CI 90-99). In the subgroup analysis, the sensitivity of ESN for PE with high or intermediate-high risk was 69% (95% CI 49-85), and the specificity was 90% (95% CI 84-94). Inter-rater reliability for ESN finding between the cardiologist and emergency physician was strong with a kappa statistic of 0.87. CONCLUSION: The pulmonary Doppler flow of ESN was moderate to high specific but low sensitive for PE in all ED patients. In the subgroup analysis, this finding was moderate specific and low sensitive.

Simple concentration method enables the use of gargle and mouthwash instead of nasopharyngeal swab sampling for the diagnosis of COVID-19 by PCR.

Since its emergence in December 2019, SARS-CoV-2 is causing one of the most devastating pandemics in human history. Currently, the most important method for definitive diagnosis of COVID-19 is identification of SARS-CoV-2 RNA in nasopharyngeal swab samples by RT-PCR. Nasopharyngeal swab sampling is a discomforting procedure sometimes with adverse effects, which also poses a risk for infection for the personnel performing the sampling. We have developed a new method for concentrating biological samples, which enabled us to use gargle and mouthwash samples to be used in RT-PCR, for the diagnosis of COVID-19, as an alternative to nasopharyngeal swab samples. We have analyzed nasopharyngeal and gargle and mouthwash samples, before and after concentration, of 363 patients by RT-PCR for the presence of SARS-CoV-2. Among 114 patients in which SARS-CoV-2 was identified in at least one of their samples, the virus was identified in 76 (66.7%), 67 (58.8%), and 101 (88.6%) of nasopharyngeal swab, gargle, and mouthwash samples before and after concentration, respectively. When concentrated by our new method, gargle and mouthwash samples can be used instead of nasopharyngeal samples in identification of SARS-CoV-2 by RT-PCR, with the same or better sensitivity. Eliminating the need for nasopharyngeal sampling will save the patients from an invasive and painful procedure and will lower the risk of infection for the healthcare personnel taking the sample. This easy sampling procedure may decrease the workload of hospitals, shorten the turnaround time of obtaining test results, and thus enable rapid isolation of infected patients.

Comparison of intravenous ibuprofen and paracetamol in the treatment of fever: A randomized double-blind study.

OBJECTIVE: Fever is one of the frequent reasons for admission to the emergency department. Studies comparing oral forms of non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol with intravenous (IV) forms for fever are common in the literature. Our study is the first emergency department study comparing IV forms of ibuprofen and paracetamol in the treatment of febrile patients. METHODS: A randomized, double-blind study was conducted in a tertiary university emergency department for a six-month period. Patients aged 18-65 years who had a fever of ≥38.0 °C were included. Patients were administered 400 mg of IV ibuprofen and 1000 mg of IV paracetamol. The primary aim of the study was to determine whether there was a difference in the effect of the two drugs on fever. The secondary aim was to investigate whether there was a difference in terms of numeric rating scale (NRS) measurements and the need for additional antipyretic therapy. RESULTS: A total of 200 people, 100 of whom were female, were included in the study. The mean age was 30.77 ± 10.61 years. The mean initial temperature for ibuprofen and paracetamol was 38.79 ± 0.470 °C and 38.70 ± 0.520 °C, respectively, with no difference noted between the groups (p = 0.380). It was found that both drugs significantly provided fever control in the first 30 min (p < 0.001), with no difference between them in terms of fever reduction (p = 0.980). Both drugs significantly improved in accompanying symptoms, although both drugs did not show superiority to each other (p = 0.0226). When evaluated in terms of a need for rescue medication, no significant difference was found between the two drugs (p = 0.404). No side effects were encountered during the study. CONCLUSION: In adult age group patients admitted to the emergency department with high fever, the IV forms of 1000 mg paracetamol and 400 mg ibuprofen effectively and equally reduce complaints, such as fever and accompanying pain. They can be effectively used as each other's rescue medicine and as an alternative to each other in patients with comorbid diseases.

Factors affecting the first-attempt success rate of intravenous cannulation in older people.

AIMS AND OBJECTIVES: To determine the factors affecting the first-attempt success of peripheral intravenous catheter (PIVC) placement in older emergency department patients. BACKGROUND: In older patients who require intravenous treatment, establishing a PIVC as fast as possible is clinically important. DESIGN: This is a prospective, observational, descriptive study. METHODS: Using a data collection form, researchers questioned both the patient and the nurse performing the procedure in terms of patient- and operator-related factors. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines (See Supporting Information Appendix S1). RESULTS: A total of 472 patients were included in the final analyses. According to the logistic regression analysis, independent factors which affected first-attempt failure were found to be: choosing a nonupper extremity site for PIVC (OR: 4.72, 95% CI: 1.35-16.45, p-value: 0.015), history of difficult intravenous access (OR: 3.02, 95% CI: 1.72-5.29, p-value: <0.001), nurse having less than 2 years of professional experience (OR: 3.45, 95% CI: 2.00-5.97, p-value: <0.001), nonpalpable veins observed after the application of tourniquet (OR: 2.21, 95% CI: 1.10-4.41, p-value: 0.025), a moderate degree of difficulty anticipated by the nurse prior to the procedure (OR: 4.32, 95% CI: 2.31-8.08, p-value: <0.001) and a high degree of difficulty anticipated by the nurse prior to the procedure (OR: 8.41, 95% CI: 4.10-17.24, p-value: <0.001). CONCLUSION: Factors affecting first-attempt success rates in peripheral intravenous catheter placement in older emergency department patients may be listed as follows: the anticipated difficulty of the procedure rated by the nurse, previous history of a difficult intravenous cannulation, choosing a nonupper extremity site for cannulation, the level of experience of the nurse and the palpability of the vein. RELEVANCE TO CLINICAL PRACTICE: Healthcare providers should consider alternative methods in the presence of factors affecting first-attempt success in older emergency department patients.

Lessons from the Hamster: Cricetulus griseus Tissue and CHO Cell Line Proteome Comparison.

Chinese hamster ovary cells represent the dominant host for therapeutic recombinant protein production. However, few large-scale data sets have been generated to characterize this host organism and derived CHO cell lines at the proteomics level. Consequently, an extensive label-free quantitative proteomics analysis of two cell lines (CHO-S and CHO DG44) and two Chinese hamster tissues (liver and ovary) was used to identify a total of 11 801 unique proteins containing at least two unique peptides. 9359 unique proteins were identified specifically in the cell lines, representing a 56% increase over previous work. Additionally, 6663 unique proteins were identified across liver and ovary tissues, providing the first Chinese hamster tissue proteome. Protein expression was more conserved within cell lines during both growth phases than across cell lines, suggesting large genetic differences across cell lines. Overall, both gene ontology and KEGG pathway analysis revealed enrichment of cell-cycle activity in cells. In contrast, upregulated molecular functions in tissue include glycosylation and lipid transporter activity. Furthermore, cellular components including Golgi apparatus are upregulated in both tissues. In conclusion, this large-scale proteomics analysis enables us to delineate specific changes between tissues and cells derived from these tissues, which can help explain specific tissue function and the adaptations cells incur for applications in biopharmaceutical productions.

Perchlorate levels found in tap water collected from several cities in Turkey.

Perchlorate is an inorganic anion that inhibits iodide transport to the thyroid by sodium-iodide transporters. Because perchlorate is highly soluble, stable, and mobile in water, drinking water is a potential source of perchlorate exposure. When exposed to perchlorate, thyroid dysfunction can be observed in sensitive populations (pregnant woman, infants, and children), especially those with iodide deficiency. The aim of this study was to determine the perchlorate levels in tap water from five cities in Turkey. Perchlorate concentrations of 145 tap water samples collected from Ankara, Isparta, Istanbul, Kayseri, and Sakarya were determined by liquid chromatography-tandem mass spectrometry. Mean and median values were found to be 0.15 and 0.07 µg/L, respectively. The median values (25-75 % percentile) of Istanbul, Ankara, Sakarya, Isparta, and Kayseri were 0.08 µg/L (0.04-0.09 µg/L), 0.07 µg/L (0.07-0.21 µg/L), 0.04 µg/L (0.04-0.04 µg/L), 0.03 µg/L (0.02-0.07 µg/L), and 0.25 µg/L (0.23-0.31 µg/L), respectively. The median perchlorate level observed in Kayseri was significantly higher than those found at other cities (p < 0.05). Perchlorate concentrations in water samples were lower than the interim drinking water health advisory level (15 µg/L) determined by the US Environmental Protection Agency. This study showed that perchlorate in drinking water is not the main source of exposure in these cities. Future studies should be performed to determine perchlorate levels in other potential sources, such as food products.

Perchlorate Exposure Through Water and Milk in Istanbul.

Perchlorate is a chemical pollutant that inhibits iodide uptake and may possibly impair thyroid function. Our previous study found widespread perchlorate exposure in non-pregnant, non-lactating, healthy women residing in Istanbul. The aim of this study is to assess the relative amounts of perchlorate exposure attributable to consumption of municipal water, bottled water and boxed milk available in Istanbul. Only trace levels of perchlorate were found in treated municipal water (58 % detectable, mean = 0.13 µg/L, maximum = 0.75 µg/L) and bottled water (7.4 % detectable, mean = 

Post-translational modifications of transthyretin affect the triiodonine-binding potential.

Transthyretin (TTR) is a visceral protein, which facilitates the transport of thyroid hormones in blood and cerebrospinal fluid. The homotetrameric structure of TTR enables the simultaneous binding of two thyroid hormones per molecule. Each TTR subunit provides a single cysteine residue (Cys10 ), which is frequently affected by oxidative post-translational modifications. As Cys10 is part of the thyroid hormone-binding channel within the TTR molecule, PTM of Cys10 may influence the binding of thyroid hormones. Therefore, we analysed the effects of Cys10 modification with sulphonic acid, cysteine, cysteinylglycine and glutathione on binding of triiodothyronine (T3) by molecular modelling. Furthermore, we determined the PTM pattern of TTR in serum of patients with thyroid disease by immunoprecipitation and mass spectrometry to evaluate this association in vivo. The in silico assays demonstrated that oxidative PTM of TTR resulted in substantial reorganization of the intramolecular interactions and also affected the binding of T3 in a chemotype- and site-specific manner with S-glutathionylation as the most potent modulator of T3 binding. These findings were supported by the in vivo results, which indicated thyroid function-specific patterns of TTR with a substantial decrease in S-sulphonated, S-cysteinylglycinated and S-glutathionylated TTR in hypothyroid patients. In conclusion, this study provides evidence that oxidative modifications of Cys10 seem to affect binding of T3 to TTR probably because of the introduction of a sterical hindrance and induction of conformational changes. As oxidative modifications can be dynamically regulated, this may represent a sensitive mechanism to adjust thyroid hormone availability.

The Efficiency of Focused Assessment with Sonography for Trauma in Pediatric Patients with Blunt Torso Trauma.

Introduction: Focused Assessment with Sonography for Trauma (FAST) has attracted attention for its use in the detection of intra-abdominal pathology for pediatric patients. However, computed tomography (CT) remains the gold standard for the assessment of blunt torso trauma. The study examines the effectiveness of FAST both in the detection of intra-abdominal pathology in pediatric patients (<19 years) with blunt torso trauma and in the determination of the need for CT for further examination. Methods: The study was designed as a retrospective observational investigation of diagnostic value. The pediatric patients who were admitted to the Emergency Department with blunt torso trauma between January 2013 and October 2016 were included in the study. The sample of the study comprised 255 patients who met the inclusion criteria. The primary outcome was the effectiveness of FAST in the detection of intra-abdominal pathology and the determination of the need for CT. The secondary outcome was to identify the agreement between CT and FAST for intra-abdominal injuries. The Chi-square test and Fisher's exact test were used for comparisons. A logistic regression model was developed to determine the variables that independently affect the agreement between FAST and CT. Results: FAST was determined to have low sensitivity (20.3%) despite its high specificity (87%). However; FAST had a good negative likelihood ratio. There was a poor agreement between CT and FAST in terms of the presence of both intra-abdominal and intrathoracic injuries in pediatric patients with blunt trunk trauma. The error rate of FAST increased by five-fold, especially in the presence of concomitant thorax trauma. However, FAST had a good negative likelihood ratio. Conclusion: FAST should not be regarded as an equivalent tool to CT for pediatric patients with blunt torso trauma. It is, instead, a noteworthy complementary tool that is a negative predictor.

Susceptibility-Weighted MRI for Predicting NF-2 Mutations and S100 Protein Expression in Meningiomas.

S100 protein expression levels and neurofibromatosis type 2 (NF-2) mutations result in different disease courses in meningiomas. This study aimed to investigate non-invasive biomarkers of NF-2 copy number loss and S100 protein expression in meningiomas using morphological, radiomics, and deep learning-based features of susceptibility-weighted MRI (SWI). This retrospective study included 99 patients with S100 protein expression data and 92 patients with NF-2 copy number loss information. Preoperative cranial MRI was conducted using a 3T clinical MR scanner. Tumor volumes were segmented on fluid-attenuated inversion recovery (FLAIR) and subsequent registration of FLAIR to high-resolution SWI was performed. First-order textural features of SWI were extracted and assessed using Pyradiomics. Morphological features, including the tumor growth pattern, peritumoral edema, sinus invasion, hyperostosis, bone destruction, and intratumoral calcification, were semi-quantitatively assessed. Mann-Whitney U tests were utilized to assess the differences in the SWI features of meningiomas with and without S100 protein expression or NF-2 copy number loss. A logistic regression analysis was used to examine the relationship between these features and the respective subgroups. Additionally, a convolutional neural network (CNN) was used to extract hierarchical features of SWI, which were subsequently employed in a light gradient boosting machine classifier to predict the NF-2 copy number loss and S100 protein expression. NF-2 copy number loss was associated with a higher risk of developing high-grade tumors. Additionally, elevated signal intensity and a decrease in entropy within the tumoral region on SWI were observed in meningiomas with S100 protein expression. On the other hand, NF-2 copy number loss was associated with lower SWI signal intensity, a growth pattern described as "en plaque", and the presence of calcification within the tumor. The logistic regression model achieved an accuracy of 0.59 for predicting NF-2 copy number loss and an accuracy of 0.70 for identifying S100 protein expression. Deep learning features demonstrated a strong predictive capability for S100 protein expression (AUC = 0.85 ± 0.06) and had reasonable success in identifying NF-2 copy number loss (AUC = 0.74 ± 0.05). In conclusion, SWI showed promise in identifying NF-2 copy number loss and S100 protein expression by revealing neovascularization and microcalcification characteristics in meningiomas.

Impact of the empirical therapy timing on the clinical progress of septic shock patients.

AIM: To evaluate the effect of timing of antimicrobial therapy on clinical progress of patients with septic shock. MATERIALS AND METHOD: We included 204 adult patients diagnosed with septic shock according to Sepsis-3 criteria between March 2016 and April 2021. One-month survival was evaluated using univariate and logistic regression analysis. RESULTS: Antibiotic treatment was initiated within 1 h of the vasopressors in 26.4 % of patients. One-month mortality did not differ significantly between patients with and without empirical therapy coverage on etiological agents. Univariate factors that significantly affected one-month survival were starting antibiotics at the first hour, the unit where the case was diagnosed with septic shock, SOFA scores, qSOFA scores, and lactate level. In multivariate analysis, diagnosis of septic shock in the Emergency Service, SOFA score ≥11, qSOFA score of three and lactate level ≥4 were significantly associated with one-month mortality. CONCLUSION: Training programs should be designed to increase the awareness of septic shock diagnosis and treatment in the Emergency Service and other hospital units. Additionally, electronic patient files should have warning systems for earlier diagnosis and consultation.

Utilizing avidity to improve antifreeze protein activity: a type III antifreeze protein trimer exhibits increased thermal hysteresis activity.

Antifreeze proteins (AFPs) are ice growth inhibitors that allow the survival of several species living at temperatures colder than the freezing point of their bodily fluids. AFP activity is commonly defined in terms of thermal hysteresis, which is the difference observed for the solution freezing and melting temperatures. Increasing the thermal hysteresis activity of these proteins, particularly at low concentrations, is of great interest because of their wide range of potential applications. In this study, we have designed and expressed one-, two-, and three-domain antifreeze proteins to improve thermal hysteresis activity through increased binding avidity. The three-domain type III AFP yielded significantly greater activity than the one- and two-domain proteins, reaching a thermal hysteresis of >1.6 °C at a concentration of <1 mM. To elucidate the basis of this increase, the data were fit to a multidomain protein adsorption model based on the classical Langmuir isotherm. Fits of the data to the modified isotherms yield values for the equilibrium binding constants for the adsorption of AFP to ice and indicate that protein surface coverage is proportional to thermal hysteresis activity.

In vitro efficacy of different PEGylation designs on cathelicidin-like peptide with high antibacterial and antifungal activity.

Recent reports on antibiotic resistance have highlighted the need to reduce the impact of this global health issue through urgent prevention and control. The World Health Organization currently considers antibiotic resistance as one of the most dangerous threats to global health. Therefore, Antimicrobial peptides (AMPs) are promising for the development of novel antibiotic molecules due to their high antimicrobial effects, non-inducing antimicrobial resistance (AMR) properties, and broad spectrum. Hence, in this study, we developed novel antimicrobial peptide/polymer conjugates to reduce the adverse effects of TN6 (RLLRLLLRLLR) peptide. We demonstrate how our constructs function in vitro in terms of antimicrobial activity, hemolytic activity, cytotoxicity, and protease resistance. Our findings show that our molecules are effective against different types of microorganisms such as Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, methicillin-resistant S. aureus, vancomycin-resistant Enteroccus faecium, and Candida albicans, which are known to be pathogenic and antibiotic-resistant. Our constructs generally showed low cytotoxicity relative to the peptide in HaCaT and 3T3 cells. Especially these structures are very successful in terms of hemotoxicity. In the bacteremia model with S. aureus, the naked peptide (TN6) was hemotoxic even at 1 µg/mL, while the hemotoxicity of the conjugates was considerably lower than the peptide. Remarkably in this model, the hemolytic activity of PepC-PEG-pepC conjugate decreased 15-fold from 2.36 to 31.12 µg/mL compared to the bacteria-free 60-min treatment. This is proof that in the case of bacteremia and sepsis, the conjugates specifically direct to bacterial cell membranes rather than red blood cells. In addition, the PepC-PEG-pepC conjugate is resistant to plasma proteases. Moreover, morphological and intracellular damage of the peptide/conjugates to Escherichia coli are demonstrated in SEM and TEM images. These results suggest our molecules can be considered potential next-generation broad-spectrum antibiotic molecule/drug candidates that might be used in clinical cases such as bacteremia and sepsis.

Bioinspired Multi-Layer Biopolymer-Based Dental Implant Coating for Enhanced Osseointegration.

The major drawbacks of metal-based implants are weak osseointegration and post-operational infections. These limitations restrict the long-term use of implants that may cause severe tissue damage and replacement of the implant. Recent strategies to enhance the osseointegration process require an elaborate fabrication process and suffer from post-operative complications. To address the current challenges taking inspiration from the extracellular matrix (ECM), the current study is designed to establish enhanced osseointegration with lowered risk of infection. Natural biopolymer pectin, peptide amphiphiles, and enzyme-mimicking fullerene moieties are governed to present an ECM-like environment around the implant surfaces. This multifunctional approach promotes osseointegration via inducing biomineralization and osteoblast differentiation. Application of the biopolymer-based composite to the metal surfaces significantly enhances cellular attachment, supports the mineral deposition, and upregulates osteoblast-specific gene expression. In addition to the osteoinductive properties of the constructed layers, the inherent antimicrobial properties of multilayer coating are also used to prevent infection possibility. The reported biopolymer-artificial enzyme composite demonstrates antimicrobial activity against Escherichia coli and Bacillus subtilis as a multifunctional surface coating.

Development and pharmaceutical investigation of novel cervical cancer-targeting and redox-responsive melittin conjugates.

Cervical cancer has recently become one of the most prevalent cancers among women throughout the world. Traditional cancer therapies generate side effects due to off-target toxicity. Thus, novel cancer medications coupled with suitable drug delivery systems are required to improve cancer therapies. Melittin peptide has a high affinity to disrupt cancer cells. In this study, we designed targeted and redox-responsive Melittin conjugates for cervical cancer and then tested them in vitro. Folic acid and squamous cell carcinoma-specific peptide (CKQNLAEG) were used as targeting agents to design various conjugates. Our findings indicate that both anticancer conjugates were effective against different cancer cell lines, including MCF-7, C33A, and HeLa. Moreover, these conjugates were found to have antioxidant and antibacterial effects as well as reduced hemolytic activity. The CM-Target (N-terminus cysteine modified-Melittin-targeting peptide-functionalized conjugate) has become more stable and acted specifically against squamous cell carcinoma, whereas folic acid (FA)-containing conjugates acted efficiently against all cancer types studied, especially for breast cancer. According to our results, these anticancer conjugates may be possible anticancer drug candidates that have fewer adverse effects.

A Novel Peptide-Based Detection of SARS-CoV-2 Antibodies.

The need for rapidly developed diagnostic tests has gained significant attention after the recent pandemic. Production of neutralizing antibodies for vaccine development or antibodies to be used in diagnostic tests usually require the usage of recombinant proteins representing the infectious agent. However, peptides that can mimic these recombinant proteins may be rapidly utilized, especially in emergencies such as the recent outbreak. Here, we report two peptides that mimic the receptor binding domain of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and investigate their binding behavior against the corresponding human immunoglobulin G and immunoglobulin M (IgG and IgM) antibodies in a clinical sample using a quartz crystal microbalance (QCM) sensor. These peptides were immobilized on a QCM sensor surface, and their binding behavior was studied against a clinical serum sample that was previously determined to be IgG and IgM-positive. It was determined that designed peptides bind to SARS-CoV-2 antibodies in a clinical sample. These peptides might be useful for the detection of SARS-CoV-2 antibodies using different methods such as enzyme-linked immunosorbent assay (ELISA) or lateral flow assays. A similar platform might prove to be useful for the detection and development of antibodies in other infections.