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Background: The COVID-19 pandemic has presented numerous challenges to the global healthcare system and emerging evidence suggests a potential link between COVID-19 treatment, specifically steroid therapy, and the development of avascular necrosis (AVN) of the hip. This review aims to provide a comprehensive overview of recent studies and case reports investigating the relationship between COVID-19, corticosteroid therapy, and the development of AVN. Understanding the nuances of AVN in the context of COVID-19 is crucial for healthcare professionals to navigate treatment decisions and mitigate potential complications. Materials and Methods: The Preferred Reporting Items for Systematic Reviews and a Meta-Analysis (PRISMA) were used in the systematic review until 1 September 2023. The full texts of the remaining twenty-three (n = 23) articles were independently reviewed by the authors of this review. Conclusions: The association between steroid therapy for COVID-19 and the development of hip AVN is a noteworthy concern even though no relationship is evident between the duration of treatment, cumulative dosage of medication, maximum daily dosage received, and presence of AVN. Further research with larger cohorts and long-term follow up is needed to better understand the causative relationship and optimal management strategies for hip AVN in the context of COVID-19 and steroid therapy.

BackgroundTransfusion-associated microchimerism implies the presence of allogeneic hematopoietic cells in an individual, following the transfusion of a blood product. It is a transfusion-related adverse effect/long-term consequence, which has not been well-investigated among regularly transfused patients with thalassemia.Patients and MethodsWe investigated 64 regularly transfused, homozygous β-thalassemic patients and 21 never-transfused healthy volunteer blood donors (controls) for the presence of microchimerism in their sera, using real-time PCR targeting circulating allogeneic, both, Human Leukocyte Antigen-DR isotype (HLA-DR) and non-HLA alleles. The investigation was longitudinally repeated in patient subsets for more than 2 years. Results were correlated with clinical and laboratory parameters, peripheral blood lymphocyte immunophenotype, blood storage time, and donor's gender to identify potential contributing factors for microchimerism generation.ResultsOverall, microchimerism was detected in 52 of the 64 patients (81.2%) and in 6 of the 21 controls (28.5%, p = 0.0001). Forty-four patients (68.7%) exhibited long-term microchimerism (persisted for more than 6 months), confirmed at all time-points investigated. Microchimerism was more frequent among elderly, women, splenectomized and more heavily transfused patients, and among those who exhibit higher serum ferritin levels. In these patients, a distinct descending pattern of CD16dim+CD56dim+ natural killer (NK)-cells (p < 0.001) and an ascending pattern of CD4+CD25brightCD127– regulatory T-cells (p = 0.022) for increasing allelic burden were noticed, suggesting the establishment of recipient immune tolerance against the donor-derived chimeric alleles. Both splenectomized and non-splenectomized thalassemic patients exhibited the same trend. The storage time of transfused blood products and donor/gender mismatch had no impact on the development of microchimerism.Discussion-Conclusive RemarksTransfusion-associated microchimerism appears to be a very common complication among multi-transfused thalassemic patients. The potential clinical consequences of this phenomenon remain as yet unclear. Immune tolerance attributed to disease itself and to repeated transfusions might at least in part explain its appearance.

Background and Objectives The greatest challenge vaccines face is that of acceptance from the general population. Healthcare professionals’ (HCPs) recommendations have significant influence on general public vaccination behavior. The aim of this study was to assess the willingness of HCPs to get vaccinated against COVID-19, two weeks before initiation of vaccinations. Materials and Methods: We conducted an anonymous online survey from 11–15 December 2020 among HCPs by emails delivered from the local medical and nursing stuff associations. Results: The 71.1% of 656 HCPs intended to accept vaccination, 5.9% did not and 23% were still undecided. The acceptance rate was higher in physicians (76.5%) and significantly lower in nurses (48.3%). Most of the responders who intended to accept vaccination were males (p = 0.01), physicians (p = 0.001), older (p = 0.02), married (p = 0.054) with children (p = 0.001), and had treated patients with COVID-19 (p < 0.001). In the multivariate logistic regression, the predictors of HCPs willingness to get vaccinated were parenthood (OR = 4.19, p = 0.003), being a physician (OR = 2.79, p = 0.04), and treating confirmed/suspected COVID-19 patients (OR = 2.87, p = 0.036). Conclusions: Low vaccination acceptance rate was found especially in nurses, and as this may have a negative impact in the vaccination compliance of the general public, interventional educational programs to enhance vaccination are crucial.

Background and objectives: During the last decade, conventional tobacco smoking is experiencing a decline and new smoking products have been introduced. IQOS (“I-Quit-Ordinary-Smoking”) is a type of “heat-not-burn” (HNB) tobacco product. The impact of IQOS on respiratory health is currently not defined. The objectives of this study were to evaluate the acute effects of IQOS on pulmonary function in non-smokers and current smokers. Materials and Methods: Fifty male healthy non-smokers and current smokers with no known co-morbidity underwent an exhaled CO measurement, oximetry (SaO2%), pulmonary function tests (flows, volumes and diffusion capacity), and a measurement of respiratory resistances with an impulse oscillometry system (IOS) before and immediately after IQOS use. Results: In the whole group of 50 participants, SaO2%, forced expiratory flow at 25% and 50% of vital capacity (FEF 25%, FEF 50%, respectively), peak expiratory flow (PEF), and diffusion lung capacity for carbon monoxide/VA (KCO) decreased significantly after IQOS use, whereas exhaled CO and airway resistance (R5 Hz, R10 Hz, r15 Hz, R20 Hz, R25 Hz, R35 Hz) increased. When the groups of smokers and non-smokers were compared, in both groups (all males, 25 smokers and 25 non-smokers), exhaled CO increased and SaO2% decreased after IQOS use (p < 0.001). In the group of non-smokers, PEF (pre 8.22 ± 2.06 vs. post 7.5 ± 2.16, p = 0.001) and FEF 25% (pre 7.6 ± 1.89 vs. 7.14 ± 2.06, p = 0.009) decreased significantly; respiratory resistances R20 Hz (pre 0.34 ± 0.1 vs. post 0.36 ± 0.09, p = 0.09) and R25 Hz (pre 0.36 ± 0.1 vs. post 0.38 ± 0.09, p = 0.08) increased almost significantly. In smokers, PEF (pre 7.69 ± 2.26 vs. post 7.12 ± 2.03, p = 0.007) and expiratory reserve volume (ERV) (pre 1.57 ± 0.76 vs. post1.23 ± 0.48, p = 0.03) decreased and R35 Hz (pre 0.36 ± 0.11 vs. post 0.39 ± 0.11, p = 0.047) increased. The differences in the changes after the use of IQOS did not differ between groups. Conclusions: IQOS had an impact on exhaled CO, SaO2%, and airways function immediately after use. Even though these changes were rather small to be considered of major clinical importance, they should raise concerns regarding the long-term safety of this product. Further research is needed for the short- and long-term effects of IQOS, especially in patients with respiratory disease.

The investigation of respiratory infections by molecular techniques provides important information about the epidemiology of respiratory disease, especially during the post-vaccination era. The objective of the present study was the detection of bacterial pathogens directly in clinical samples from patients with upper and lower respiratory tract infections using multiplex polymerase chain reaction (PCR) assays developed in our laboratory. Clinical samples taken over a three-year period (2007–2009) and obtained from 349 patients (adults (n = 66); children (n = 283)) with signs and symptoms of certain upper or lower respiratory tract infections, consisted of: bronchoalveolar lavages (BAL, n = 83), pleural fluids (n = 29), and middle-ear aspirates (n = 237). Overall, 212 samples (61%) were confirmed by culture and/or PCR. Among the positive samples, Streptococcus pneumoniae (mainly serotype 3) was predominant (104/212; 49.0%), followed by non-typable Haemophilus influenzae (NTHi) 59/212; 27.8%) and Streptococcus pyogenes (47/212; 22%). Haemophilus influenzae type b was detected in only three samples. The underlying microbiology of respiratory infections is gradually changing in response to various selective pressures, such as vaccine use and antibiotic consumption. The application of multiplex PCR (mPCR) assays is particularly useful since it successfully identified the microorganisms implicated in acute otitis media or lower respiratory tract infections in nearly 75% of patients with a positive result compared to conventional cultures. Non-culture identification of the implicated pneumococcal serotypes is also an important issue for monitoring pneumococcal infections in the era of conjugate pneumococcal vaccines.

A new 2,4-dinitrophenylhydrazine (DNPH)-based photometric assay is developed for the quantification of carbonyls in protein samples from any biological source by protein carbonyl-DNPH hydrazone formation at acidic pH in the presence of denaturing urea, and subsequent hydrazone solubilization in the presence of SDS and stabilization from acid hydrolysis at pH 7.0. At this neutral (ntr) pH, interfering unreacted DNPH is uncharged and its thus increased hydrophobicity permits its 100% effective removal from the solubilizate with ethyl acetate/hexane wash. The ntrDNPH assay is more reliable and sensitive than the standard (std) DNPH photometric assay because it eliminates its main limitations: (i) interfering unreacted DNPH (pKa 1.55) that is nonspecifically bound to the TCA (pKa 0.7)-protein pellet is not effectively removed after wash with EtOH: ethyl acetate because it is positively charged, (ii) acid (TCA-induced) hydrolysis of the protein carbonyl-DNPH hydrazone, (iii) sample protein concentration re-determination, (iv) loss of sample acid (TCA)-soluble proteins, (v) DNA interference, and (vi) requires high protein quantity samples (≥ 1 mg). Considering ntrDNPH assay’s very low protein limit (1 µg), its cumulative and functional sensitivities are 2600- and 2000-fold higher than those of the stdDNPH assay, respectively. The present study elucidates the DNA interference mechanism on the stdDNPH assay, and also develops a standardized protocol for sample protein treatment and fractionation (into cytoplasmic/aqueous, membrane/lipid-bound, and histone/DNA-bound proteins; see Supplement section V) in order to ensure reproducible carbonyl determination on defined cell protein fractions, and to eliminate assay interference from protein samples containing (i) Cys sulfenic acid groups (via their neutralization with dithiothreitol), and (ii) DNA (via its removal by streptomycin sulfate precipitation). Lastly, the ntrDNPH assay determines carbonyl groups on cell wall polysaccharides, thus paving the way on studies to investigate cell walls acting as antioxidant defense in plants, fungi, bacteria and lichens. Keywords: Photometric method, 2,4-dinitrophenylhydrazine, Protein carbonyls, Cell wall polysaccharide carbonyls, Oxidative stress, DNA interference, Protein fractionation

A new fluorometric assay is presented for the ultrasensitive quantification of total protein carbonyls, and is based on their specific reaction with rhodamine B hydrazide (RBH), and the production of a protein carbonyl-RBH hydrazone the fluorescence of which (at ex/em 560/585 nm) is greatly enhanced by guanidine-HCl. Compared to the fluorescein-5-thiosemicarbazide (FTC)-based fluorometric assay, the RBH assay uses a 24-fold shorter reaction incubation time (1 h) and at least 1000-fold lower protein quantity (2.5 µg), and produces very reliable data that were verified by extensive standardization experiments. The protein carbonyl group detection sensitivity limit of the RBH assay, based on its standard curve, can be as low as 0.4 pmol, and even lower. Counting the very low protein limit of the RBH assay, its cumulative and functional sensitivity is 8500- and 800-fold higher than the corresponding ones for the FTC assay. Neither heme proteins hemoglobin and cytochrome c nor DNA interfere with the RBH assay. Keywords: Fluorometric method, Rhodamine B hydrazide, Protein carbonyls, Protein oxidation, Oxidative stress, DNA

Natural products are characterized by extreme structural diversity and thus they offer a unique source for the identification of novel anti-tumor agents. Herein, we report that the herbal substance acteoside being isolated by advanced phytochemical methods from Lippia citriodora leaves showed enhanced cytotoxicity against metastatic tumor cells; acted in synergy with various cytotoxic agents and it sensitized chemoresistant cancer cells. Acteoside was not toxic in physiological cellular contexts, while it increased oxidative load, affected the activity of proteostatic modules and suppressed matrix metalloproteinases in tumor cell lines. Intraperitoneal or oral (via drinking water) administration of acteoside in a melanoma mouse model upregulated antioxidant responses in the tumors; yet, only intraperitoneal delivery suppressed tumor growth and induced anti-tumor-reactive immune responses. Mass-spectrometry identification/quantitation analyses revealed that intraperitoneal delivery of acteoside resulted in significantly higher, vs. oral administration, concentration of the compound in the plasma and tumors of treated mice, suggesting that its in vivo anti-tumor effect depends on the route of administration and the achieved concentration in the tumor. Finally, molecular modeling studies and enzymatic activity assays showed that acteoside inhibits protein kinase C. Conclusively, acteoside holds promise as a chemical scaffold for the development of novel anti-tumor agents. Keywords: Acteoside, Cancer, Natural compound, Oxidative stress, Proteostasis, Immunomodulation

Cogan’s syndrome is a rare disorder characterized by ocular and audiovestibular manifestations in its typical form and caries a wide variety of atypical manifestations. It is considered as an autoimmune disease. We present the first case in the literature of a 67 year old woman with the development of low grade non-Hodgkin lymphoma (NHL) in the mastoid bone in a pre-existing history of atypical Cogan’s syndrome. The anatomical development of NHL was to a “target” organ of Cogan’s syndrome, which is the inner ear.