Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 70
1.
Head Neck Pathol ; 18(1): 48, 2024 Jun 17.
Article En | MEDLINE | ID: mdl-38884816

BACKGROUND: Craniofacial osteosarcomas (CFOS) are uncommon malignant neoplasms of the head and neck with different clinical presentation, biological behavior and prognosis from conventional osteosarcomas of long bones. Very limited genetic data have been published on CFOS. METHODS: In the current study, we performed comprehensive genomic studies in 15 cases of high-grade CFOS by SNP array and targeted next generation sequencing. RESULT: Our study shows high-grade CFOS demonstrate highly complex and heterogenous genomic alterations and harbor frequently mutated tumor suppressor genes TP53, CDKN2A/B, and PTEN, similar to conventional osteosarcomas. Potentially actionable gene amplifications involving CCNE1, AKT2, MET, NTRK1, PDGFRA, KDR, KIT, MAP3K14, FGFR1, and AURKA were seen in 43% of cases. GNAS hotspot activating mutations were also identified in a subset of CFOS cases, with one case representing malignant transformation from fibrous dysplasia, suggesting a role for GNAS mutation in the development of CFOS. CONCLUSION: High-grade CFOS demonstrate highly complex and heterogenous genomic alterations, with amplification involving receptor tyrosine kinase genes, and frequent mutations involving tumor suppressor genes.


DNA Copy Number Variations , High-Throughput Nucleotide Sequencing , Osteosarcoma , Humans , Female , Male , Adult , Osteosarcoma/genetics , Osteosarcoma/pathology , Middle Aged , Adolescent , Mutation , Child , Young Adult , Aged , Bone Neoplasms/genetics , Bone Neoplasms/pathology , Skull Neoplasms/genetics , Skull Neoplasms/pathology , DNA Mutational Analysis
3.
Article En | MEDLINE | ID: mdl-38686504

CONTEXT: Serum thyroglobulin (Tg) measured by Immunometric assays (IMA) is prone to underestimation due to Tg autoantibody (TgAb) interference, often prompting reflex Tg measurement by liquid chromatography/tandem mass spectrometry (MS) or radioimmunoassay (RIA). OBJECTIVE: IMA, MS and RIA methodologies were used to measure serum Tg in TgAb-negative (TgAb-) and TgAb-positive (TgAb+) patients with either distant metastatic thyroid cancer (DTC) or hyperthyroidism (HY) - patients in whom a detectable serum Tg would be expected. CONCLUSIONS: 1) Between-method Tg variability necessitates method continuity when monitoring the Tg trends of TgAb- DTC patients. 2) The presence and concentration of TgAb appeared to have a lowering effect on serum Tg measured by all methodologies (IMA, MS and RIA). 3) Since the reliability of Tg measured in the presence of TgAb is often uncertain, the TgAb trend (measured by the same method) may be a useful surrogate DTC tumor marker.

4.
Work ; 2023 Dec 16.
Article En | MEDLINE | ID: mdl-38143414

BACKGROUND: The academic environment is known for its high demands in research, teaching, and administration, that along with increasing publish or perish culture can lead to reduced psychological well-being and mental health issues. OBJECTIVE: This study aimed to investigate the associations between workaholism, work engagement, and burnout among academics in Montenegro. METHODS: A cross-sectional design was used to develop anonymous online survey. Data was collected from 131 participants employed as teaching and research staff at public and private universities. To measure the variables of interest we used: ultra-short Utrecht Work Engagement Scale (UWES-3), the work-related burnout subscale from the Copenhagen Burnout Inventory (CBI-7) and the Dutch Work Addiction Scale (DUWAS-10). Psychometric network analysis was employed to examine the relationships among variables. RESULTS: The findings revealed two distinct clusters: the first containing the dimensions of work engagement and the second containing burnout and the dimensions of workaholism. The two clusters were connected with the dimensions of dedication - burnout having the strongest edge (-0.25 and -0.40). In the cross-sample network the strongest connection was burnout -working excessively (.35). No significant differences in network density (0.80 (12/15 edges)) and global strength (p = 0.159) in the networks of public and private universities were found. CONCLUSION: Results of the network centrality and the edge strength analyses suggest that the interventions focused at increasing dedication while not fostering a work environment that encourages working excessively might be the key to preventing and reducing burnout in academia across contexts of public and private universities.

5.
J Electromyogr Kinesiol ; 73: 102828, 2023 Dec.
Article En | MEDLINE | ID: mdl-37782992

The aim of the study was to assess the potential influence of footedness and dominance on maximal force, force fluctuations and neural drive during dorsiflexion. Fifteen left-footed (LF) and fifteen right-footed (RF) young adults performed 2 maximal voluntary contractions (MVC) and 3 steady submaximal isometric contractions at five target forces (5, 10, 20, 40 and 60% MVC) with the dorsiflexors of both legs. High-density electromyography (EMG) was used to record the discharge characteristics of motor units (MUs) of Tibialis Anterior. MVC force and EMG amplitude (root mean square) were similar between the two legs and groups (p > 0.05). Force fluctuations (Coefficient of Variation, CoV for force), mean discharge rate of MUs, discharge variability (CoV of interspike interval), and variability in neural drive (standard deviation of filtered cumulative spike train) were greater (p < 0.05) and the input-output gain of the MUs (ΔDR/ΔF) was lower (p < 0.05) for the LF relative to the RF group. The differences in force fluctuations during steady contractions with the dorsiflexors were associated with footedness but not with dominance. They reflect greater variability in motor neuron output, as suggested by coefficient of variation for interspike interval (independent input) and the standard deviation of the smoothed discharge times (common input).


Isometric Contraction , Muscle, Skeletal , Male , Young Adult , Humans , Muscle, Skeletal/physiology , Electromyography , Isometric Contraction/physiology , Lower Extremity , Foot , Muscle Contraction/physiology
6.
Arch Oral Biol ; 156: 105808, 2023 Dec.
Article En | MEDLINE | ID: mdl-37778290

OBJECTIVE: To investigate the influence of strain differences in immune response on the pathogenesis of oral candidiasis in Dark Agouti (DA) and Albino Oxford (AO) inbred strains of rats. DESIGN: Seventy male 8-weeks old DA and AO rats were inoculated with Candida albicans to induce three different experimental models of oral candidiasis, one immunocompetent and two immunocompromised models. The animals were sacrificed after 16 days from the beginning of the experiment followed by collecting the samples of the tongue dorsum and blood for histopathological (PAS and H&E staining), immunohistochemical, qRT-PCR, and oxidative stress analyses. RESULTS: Histopathological and immunohistochemical analyses revealed lower levels of epithelial colonization, epithelial damage, and inflammatory infiltration in DA compared to AO strain of rats. DA rats had fewer CD45, CD68, and CD3 positive cells but more HIS 48 positive cells than AO rats. The expressions of IL-1ß, TNFα, IFN-γ, IL-10 and TGF-ß1 were consistently higher in DA strain across all experimental models. However, the expressions of IL-4 and IL-17 differed inconsistently between DA and AO strain in various experimental models. Strain differences were observed in levels of prooxidative hydrogen peroxide and lipid peroxidation, with higher levels presented in AO rats compared to DA rats, while antioxidative parameters presented little yet inconsistent difference between strains. CONCLUSION: DA strain of rats consistently presented lower susceptibility to oral infection with C. albicans compared to AO strain with robust Th1/Th17 immune response indicating the importance of the genetic background on the development of oral candidiasis.


Candida albicans , Candidiasis, Oral , Rats , Animals , Male , Immunity
7.
Acta Microbiol Immunol Hung ; 70(3): 187-192, 2023 Sep 21.
Article En | MEDLINE | ID: mdl-37535440

The study aimed to investigate prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) blood culture isolates and their susceptibility to two new antibiotics, imipenem/relebactam and ceftazidime/avibactam. Out of 765 isolates recovered from blood cultures in a tertiary care hospital in Serbia between 2020 and 2023, 143 non-repetitive K. pneumoniae strains were included in this study. Minimum inhibitory concentration (MIC) values of the examined antimicrobial drugs was determined by VITEK 2 system, MIC test strip (imipenem/relebactam and ceftazidime/avibactam), and broth microdilution method (tigecycline and colistin). Carbapenemase-encoding genes (blaKPC, blaOXA-48-like, blaNDM, blaVIM, blaIMP) were detected using a multiplex-PCR assay, the BioFire-Blood Culture Identification 2-panel. This closed molecular assay is designed for the BioFire® FilmArray® system, enabling automated sample preparation, amplification, detection, and analysis (bioMérieux, France). Results revealed that K. pneumoniae was the most common isolate from blood cultures in 2022. The prevalence of K. pneumoniae was about 11.6% in 2020 and 2021, while in 2022 it raised to over 30%. Also, the frequency of CRKP increased from 11.76% in 2020, through 15.29% in 2021 to 72.94% in 2022. The majority of CRKP carried blaOXA-48-like (60.0%), followed by blaKPC (16.47%), and blaNDM (8.24%) genes, while 14.12% harboured both blaOXA-48-like and blaNDM genes. Only 25.88% of CRKP isolates were resistant to ceftazidime/avibactam, while 51.76% were resistant to imipenem/relebactam and colistin. The rapid spread of CRKP is particularly concerning because therapeutic options are limited to a few antibiotics. While imipenem/relebactam and colistin showed similar antimicrobial activity against CRKP clinical isolates, ceftazidime/avibactam proved to be the most effective antibiotic.


Carbapenem-Resistant Enterobacteriaceae , Klebsiella Infections , Humans , Ceftazidime/pharmacology , Blood Culture , Klebsiella pneumoniae , Colistin/pharmacology , Serbia/epidemiology , Klebsiella Infections/epidemiology , Klebsiella Infections/drug therapy , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , beta-Lactamases/genetics , Bacterial Proteins/genetics , Drug Combinations , Hospitals, University , Imipenem/pharmacology , Imipenem/therapeutic use , Carbapenems/pharmacology , Microbial Sensitivity Tests
8.
J Cardiovasc Dev Dis ; 10(7)2023 Jul 12.
Article En | MEDLINE | ID: mdl-37504552

The successful outcome of a cardiac surgery procedure is significantly dependent on the management of cardiopulmonary bypass (CPB). Even if a cardiac operation is technically well-conducted, a patient may suffer CPB-related complications that could result in severe comorbidities, reduced quality of life, or even death. However, the role of clinical perfusionists in perioperative patient care, which is critical, is often overlooked. Therefore, the European Association for Cardio-Thoracic Surgery (EACTS), the European Association of Cardiothoracic Anaesthesiology (EACTA), and the European Board of Cardiovascular Perfusion (EBCP) have agreed to develop joint clinical practice guidelines (CPGs) for CPB due to its significant impact on patient care and significant variations in practice patterns between countries. The European guidelines, based on the EACTS standardized framework for the development of CPGs, cover the entire spectrum of CPB management in adult cardiac surgery. This includes training and education of clinical perfusionists, machine hardware, disposables, preparation for initiation of CPB, a complete set of procedures during CPB to help maintain end-organ function and anticoagulation, weaning from CPB, and the gaps in evidence and future research directions. This comprehensive coverage ensures that all aspects of CPB management are addressed, providing clinicians with a standardized approach to CPB management based on the latest evidence and best practices. To ensure better integration of these evidence-based recommendations into daily practice, this review aims to provide a general understanding of guideline development and an overview of essential treatment recommendations for CPB management.

9.
Front Neurol ; 14: 1135472, 2023.
Article En | MEDLINE | ID: mdl-37360342

Objective: Delirium is associated with worse outcomes in patients with stroke and neurocritical illness, but delirium detection in these patients can be challenging with existing screening tools. To address this gap, we aimed to develop and evaluate machine learning models that detect episodes of post-stroke delirium based on data from wearable activity monitors in conjunction with stroke-related clinical features. Design: Prospective observational cohort study. Setting: Neurocritical Care and Stroke Units at an academic medical center. Patients: We recruited 39 patients with moderate-to-severe acute intracerebral hemorrhage (ICH) and hemiparesis over a 1-year period [mean (SD) age 71.3 (12.20), 54% male, median (IQR) initial NIH Stroke Scale 14.5 (6), median (IQR) ICH score 2 (1)]. Measurements and main results: Each patient received daily assessments for delirium by an attending neurologist, while activity data were recorded throughout each patient's hospitalization using wrist-worn actigraph devices (on both paretic and non-paretic arms). We compared the predictive accuracy of Random Forest, SVM and XGBoost machine learning methods in classifying daily delirium status using clinical information alone and combined with actigraph data. Among our study cohort, 85% of patients (n = 33) had at least one delirium episode, while 71% of monitoring days (n = 209) were rated as days with delirium. Clinical information alone had a low accuracy in detecting delirium on a day-to-day basis [accuracy mean (SD) 62% (18%), F1 score mean (SD) 50% (17%)]. Prediction performance improved significantly (p < 0.001) with the addition of actigraph data [accuracy mean (SD) 74% (10%), F1 score 65% (10%)]. Among actigraphy features, night-time actigraph data were especially relevant for classification accuracy. Conclusions: We found that actigraphy in conjunction with machine learning models improves clinical detection of delirium in patients with stroke, thus paving the way to make actigraph-assisted predictions clinically actionable.

10.
J Sports Sci Med ; 22(2): 245-253, 2023 Jun.
Article En | MEDLINE | ID: mdl-37293414

The aim of the study was to assess the influence of habitual training history on force steadiness and the discharge characteristics of motor units in tibialis anterior during submaximal isometric contractions. Fifteen athletes whose training emphasized alternating actions (11 runners and 4 cyclists) and fifteen athletes who relied on bilateral actions with leg muscles (7 volleyball players, 8 weight-lifters) performed 2 maximal voluntary contractions (MVC) with the dorsiflexors, and 3 steady contractions at 8 target forces (2.5%, 5%, 10%, 20%, 30%, 40%, 50% and 60% MVC). The discharge characteristics of motor units in tibialis anterior were recorded using high-density electromyography grids. The MVC force and the absolute (standard deviation) and normalized (coefficient of variation) amplitudes of the force fluctuations at all target forces were similar between groups. The coefficient of variation for force decreased progressively from 2.5% to 20% MVC force, then it plateaued until 60% MVC force. Mean discharge rate of the motor units in tibialis anterior was similar at all target forces between groups. The variability in discharge times (coefficient of variation for interspike interval) and the variability in neural drive (coefficient of variation of filtered cumulative spike train) was also similar for the two groups. These results indicate that athletes who have trained with either alternating or bilateral actions with leg muscles has similar effects on maximal force, force control, and variability in the independent and common synaptic input during a single-limb isometric task with the dorsiflexors.


Leg , Muscle, Skeletal , Humans , Muscle, Skeletal/physiology , Electromyography , Isometric Contraction/physiology , Exercise
11.
Mol Cell ; 83(12): 2108-2121.e7, 2023 Jun 15.
Article En | MEDLINE | ID: mdl-37244255

The two non-visual arrestins, arrestin2 and arrestin3, bind hundreds of GPCRs with different phosphorylation patterns, leading to distinct functional outcomes. Structural information on these interactions is available only for very few GPCRs. Here, we have characterized the interactions between the phosphorylated human CC chemokine receptor 5 (CCR5) and arrestin2. We identified several new CCR5 phosphorylation sites necessary for stable arrestin2 complex formation. Structures of arrestin2 in the apo form and complexes with CCR5 C-terminal phosphopeptides, together with NMR, biochemical, and functional assays, revealed three phosphoresidues in a pXpp motif that are essential for arrestin2 binding and activation. The identified motif appears responsible for robust arrestin2 recruitment in many other GPCRs. An analysis of receptor sequences and available structural and functional information provides hints on the molecular basis of arrestin2/arrestin3 isoform specificity. Our findings demonstrate how multi-site phosphorylation controls GPCR⋅arrestin interactions and provide a framework to probe the intricate details of arrestin signaling.


Phosphopeptides , Receptors, CCR5 , Humans , Phosphorylation , beta-Arrestins/metabolism , Phosphopeptides/metabolism , Receptors, CCR5/metabolism , Cell Line
12.
Tex Heart Inst J ; 50(1)2023 01 01.
Article En | MEDLINE | ID: mdl-36735614

BACKGROUND: The optimal treatment strategy for patients with severe carotid artery disease undergoing coronary artery bypass grafting is still problematic. The important question is whether it is necessary to treat significant carotid disease in patients who have undergone coronary artery bypass grafting. This study analyzed short- and midterm results after same-day carotid artery stenting and coronary artery bypass grafting. METHODS: From 2013 to 2020, a total of 69 patients were enrolled in the study. Same-day carotid artery stenting and coronary artery bypass grafting were performed in all patients. The study's primary end points were the evaluation rate of stroke, myocardial infarction, and death within short- and midterm periods after the procedures. RESULTS: The 30-day mortality was 0%. The occurrences of perioperative adverse events, namely stroke, myocardial infarction, and transient ischemic attack, were 1 (1.4%), 1 (1.4%), and 4 (5.8%), respectively. Mean (IQR) follow-up time was 28 (IQR, 17-43) months. Six (8.8%) patients died during this period. Fatal stroke was registered in 2 cases, and 1 patient experienced a disabling stroke with a fatal outcome. The other 3 patients died because of chronic renal disease, a traffic accident, and for an unknown reason, respectively. Midterm survival in the group was 91.2%. CONCLUSION: The study showed that same-day carotid artery stenting and coronary artery bypass grafting for concomitant carotid and coronary disease treatment could be a promising and feasible therapeutic strategy.


Carotid Stenosis , Coronary Artery Disease , Endarterectomy, Carotid , Myocardial Infarction , Stroke , Humans , Carotid Stenosis/complications , Carotid Stenosis/diagnosis , Carotid Stenosis/surgery , Stents/adverse effects , Coronary Artery Bypass/adverse effects , Coronary Artery Disease/diagnosis , Coronary Artery Disease/surgery , Coronary Artery Disease/complications , Myocardial Infarction/complications , Stroke/etiology , Carotid Arteries , Treatment Outcome
13.
Paediatr Int Child Health ; 42(2): 59-66, 2022 05.
Article En | MEDLINE | ID: mdl-35944175

Legionnaires' disease is an atypical pneumonia caused by inhaling small droplets of water containing the bacterium Legionella spp. In newborns, it is a rare event, usually associated with water births and the use of air conditioning systems or air humidifiers. A nosocomial outbreak of Legionnaires' disease in the maternity ward of a secondary-care hospital in Arandjelovac, Serbia is described.Two male newborns were found to be infected with Legionnella pneumophila. On Days 7 and 6 of life, respectively, they were transferred to a tertiary-care hospital with signs of severe pneumonia which was radiologically confirmed. L. pneumophila was detected in tracheal secretions from both infants by RT-PCR, and its antigens were also positive in urine samples. The source of infection in the secondary-care hospital was the internal hot water heating system, and the main contributory factor to the emergence of the infection was the low temperature of the hot water which did not kill the bacteria during the available exposure time.These two cases highlight the importance of being cautious about possible Legionnaires' disease in maternity wards with outdated or irregularly maintained internal water supply systems. The adoption of official guidelines for the control and regular maintenance of water supply systems, including the multidisciplinary cooperation of all relevant parties, forms the basis for direct monitoring for Legionella and the prevention of new outbreaks.Abbreviations: BCYE: buffered charcoal yeast extract agar; GVPC: glycine vancomycin polymyxin cycloheximide agar; LD - Legionnaires' disease; TR-PCR: Reverse transcription polymerase chain reaction.


Legionella pneumophila , Legionnaires' Disease , Pneumonia , Agar , Charcoal , Cycloheximide , Disease Outbreaks , Female , Glycine , Humans , Infant, Newborn , Legionnaires' Disease/diagnosis , Legionnaires' Disease/epidemiology , Legionnaires' Disease/microbiology , Male , Polymyxins , Pregnancy , Serbia/epidemiology , Vancomycin , Water , Water Microbiology
14.
Methods Cell Biol ; 169: 115-141, 2022.
Article En | MEDLINE | ID: mdl-35623699

The numerous chemokines and their cognate G protein-coupled chemokine receptors on the surface of leukocytes form a complex signaling network, which regulates the immune response and also other key physiological processes. Currently only a very limited number of structures of chemokine•chemokine receptor complexes have been solved. More structures are needed for the understanding of their mechanism of action and the rational design of drugs against these highly relevant therapeutic targets. Recently, we have determined the cryo-EM structure of the human wild-type CCR5 chemokine receptor, which is also the HIV-1 coreceptor, in its active conformation bound to the chemokine super-agonist [6P4]CCL5 and the heterotrimeric Gi protein. The structure provides the rationale for the sequence-activity relation of agonist and antagonist CCR5 chemokine ligands. In this chapter, we present a detailed protocol for the preparation of the active agonist chemokine•CCR5•Gi complex for cryo-EM studies including quality controls and caveats. As such the protocol may serve as starting point for structural and biophysical studies of other chemokine•chemokine receptor complexes.


Receptors, CCR5 , Signal Transduction , Chemokine CCL5/chemistry , Chemokines/metabolism , Cryoelectron Microscopy , Humans , Receptors, CCR5/chemistry , Receptors, CCR5/metabolism , Receptors, G-Protein-Coupled
15.
Med Sci Sports Exerc ; 54(8): 1278-1287, 2022 08 01.
Article En | MEDLINE | ID: mdl-35324535

PURPOSE: The aim of our study was to compare maximal force, force steadiness, and discharge characteristics of motor units in tibialis anterior during contractions with the dorsiflexors of the dominant and nondominant legs at low-to-moderate target forces and three ankle angles. METHODS: Twenty young adults performed maximal and submaximal isometric contractions (5%, 10%, 20%, 40%, and 60% of maximal voluntary contraction (MVC)) with the dorsiflexors of the dominant and nondominant legs at three ankle angles (75°, short length; 90°, intermediate length; 105°, long length). High-density EMG signals from the tibialis anterior muscle of each leg were recorded. RESULTS: Maximal force (average dominant, 182.9 ± 64.5 N; nondominant, 179.0 ± 58.8 N) and the fluctuations in force, quantified as absolute (SD) and normalized amplitudes (coefficient of variation (CoV)), were similar between the two legs across the three ankle angles (average CoV for dominant, 1.5% ± 1.0%; nondominant, 1.7% ± 1.3%). The CoV for force for both legs decreased from 5% to 20% MVC force, and then it plateaued at 40% and 60% MVC force. EMG amplitude, mean discharge rate of motor units, discharge variability (interspike interval), and the variability in neural drive (filtered cumulative spike train) were similar between the two legs across the submaximal contractions. CONCLUSIONS: MVC force and force steadiness were similar across ankle angles and target forces between the dominant and nondominant legs. The attributes that underlie the self-reported identification of a dominant leg were not associated with the force capacity or the control of force for the dorsiflexor muscles, at least during isometric contractions.


Leg , Patient Discharge , Ankle/physiology , Electromyography , Humans , Isometric Contraction/physiology , Leg/physiology , Muscle Contraction/physiology , Muscle, Skeletal/physiology , Young Adult
16.
Germs ; 12(4): 434-443, 2022 Dec.
Article En | MEDLINE | ID: mdl-38021186

Introduction: This study aimed to determine the prevalence of multidrug-resistant Gram-negative bacteria (GNB) from blood cultures in a tertiary-care hospital and the multiplex PCR assay's ability to detect resistance genes. Methods: A total of 388 GNB isolates obtained from hospitalized patients between November 2019 and November 2021 were included in the study. Antimicrobial susceptibility testing was done by VITEK 2 system and broth microdilution method. Beta-lactamase-encoding genes were detected by multiplex PCR assays, BioFire-Blood Culture Identification 2 (BCID2) panel (bioMérieux, France). Extended-spectrum beta-lactamases (ESBLs) were detected phenotypically with VITEK AST-GN71 card (bioMérieux, France). The isolates of GNB were classified into multidrug-resistant, extensively-drug-resistant, and pandrug-resistant categories, and their prevalence and distribution in different wards, including coronavirus diseases 2019 (COVID-19) intensive care units (ICU), were calculated. Results: Results revealed that all isolates of Acinetobacter baumannii and Pseudomonas aeruginosa were multidrug-resistant as well as 91.6% of Enterobacter cloacae, 80.6% of Proteus mirabilis, and 76.1% of Klebsiella pneumoniae, respectively. In fermentative bacteria, blaOXA-48-like (58.1%), blaNDM (16.1%), blaKPC (9.7%) and blaVIM (6.5%) genes were detected. More than half of Enterobacter cloacae (58.3%) and Klebsiella pneumoniae (53.7%) produced ESBLs. Among non-fermenters, the blaNDM gene was carried by 55% of Pseudomonas aeruginosa and 19.5% of Acinetobacter baumannii. In the COVID-19 ICU, Acinetobacter baumannii was the most common isolate (86.1%). Conclusions: This study revealed high proportions of multidrug-resistant blood isolates and various underlying resistance genes in Gram-negative strains. The BCID2 panel seems to be helpful for the detection of the most prevalent resistance genes of fermentative bacteria.

17.
Elife ; 102021 08 09.
Article En | MEDLINE | ID: mdl-34369377

The microtubule-associated protein, tau, is the major subunit of neurofibrillary tangles associated with neurodegenerative conditions, such as Alzheimer's disease. In the cell, however, tau aggregation can be prevented by a class of proteins known as molecular chaperones. While numerous chaperones are known to interact with tau, though, little is known regarding the mechanisms by which these prevent tau aggregation. Here, we describe the effects of ATP-independent Hsp40 chaperones, DNAJA2 and DNAJB1, on tau amyloid-fiber formation and compare these to the small heat shock protein HSPB1. We find that the chaperones play complementary roles, with each preventing tau aggregation differently and interacting with distinct sets of tau species. Whereas HSPB1 only binds tau monomers, DNAJB1 and DNAJA2 recognize aggregation-prone conformers and even mature fibers. In addition, we find that both Hsp40s bind tau seeds and fibers via their C-terminal domain II (CTDII), with DNAJA2 being further capable of recognizing tau monomers by a second, distinct site in CTDI. These results lay out the mechanisms by which the diverse members of the Hsp40 family counteract the formation and propagation of toxic tau aggregates and highlight the fact that chaperones from different families/classes play distinct, yet complementary roles in preventing pathological protein aggregation.


Several neurological conditions, such as Alzheimer's and Parkinson's disease, are characterized by the build-up of protein clumps known as aggregates. In the case of Alzheimer's disease, a key protein, called tau, aggregates to form fibers that are harmful to neuronal cells in the brain. One of the ways our cells can prevent this from occurring is through the action of proteins known as molecular chaperones, which can bind to tau proteins and prevent them from sticking together. Tau can take on many forms. For example, a single tau protein on its own, known as a monomer, is unstructured. In patients with Alzheimer's, these monomers join together into small clusters, known as seeds, that rapidly aggregate and accumulate into rigid, structured fibers. One chaperone, HSPB1, is known to bind to tau monomers and prevent them from being incorporated into fibers. Recently, another group of chaperones, called J-domain proteins, was also found to interact with tau. However, it was unclear how these chaperones prevent aggregation and whether they bind to tau in a similar manner as HSPB1. To help answer this question, Irwin, Faust et al. studied the effect of two J-domain proteins, as well as the chaperone HSBP1, on tau aggregation. This revealed that, unlike HSBP1, the two J-domain proteins can bind to multiple forms of tau, including when it has already aggregated in to seeds and fibers. This suggests that these chaperones can stop the accumulation of fibers at several different stages of the aggregation process. Further experiments examining which sections of the J-domain proteins bind to tau, showed that both attach to fibers via the same region. However, the two J-domain proteins are not identical in their interaction with tau. While one of them uses a distinct region to bind to tau monomers, the other does not bind to single tau proteins at all. These results demonstrate how different cellular chaperones can complement one another in order to inhibit harmful protein aggregation. Further studies will be needed to understand the full role of J-domain proteins in preventing tau from accumulating into fibers, as well as their potential as drug targets for developing new treatments.


HSP40 Heat-Shock Proteins/metabolism , tau Proteins/chemistry , tau Proteins/metabolism , Amyloidogenic Proteins , Escherichia coli , HSP40 Heat-Shock Proteins/genetics , Mutation , Protein Aggregation, Pathological , tau Proteins/genetics
18.
Bioelectromagnetics ; 42(3): 238-249, 2021 Apr.
Article En | MEDLINE | ID: mdl-33544924

Different priming methods were developed to improve seed germination and the early growth of seedlings. This study aimed to examine the combined effect of bacterial inoculation and static magnetic field on white mustard (Sinapis alba L.) germination. A plant growth-promoting bacterial strain Bacillus amyloliquefaciens D5 ARV was used for biopriming. The static magnetic field of 90 mT was applied for 5 and 15 min. Analyses of abscisic acid, chlorophyll, anthocyanins, flavonoids content, nitrogen balance index, and bacterial indole-3-acetic acid were used to explain observed effects. Bacterial inoculation improved seed germination, whereas exposure to 90 mT for 15 min suppressed germination. Such an unfavorable effect was neutralized when the treatment with the static magnetic field was combined with bacterial inoculation. The highest germination percentage was a result of synergistic action of B. amyloliquefaciens D5 ARV and 15 min long exposure to 90 mT, which induced an increase of 53.20% in the number of germinated seeds. The static magnetic field induced the increase of bacterial indole-3-acetic acid production threefold times. Biomagnetic priming caused a metabolic shift from primary to secondary metabolism in the white mustard seedlings. An adequate combination of biological priming and static magnetic field treatment can be successfully used in old seed revitalization and germination improvements. © 2021 Bioelectromagnetics Society.


Anthocyanins , Germination , Chlorophyll , Seedlings , Seeds
19.
Physiol Mol Biol Plants ; 27(12): 2805-2817, 2021 Dec.
Article En | MEDLINE | ID: mdl-35035137

Water deficit triggers physiological, biochemical, and molecular changes in leaves that could be important for overall plant adaptive response and it can affect tomato yield and quality. To assess the influence of long-term moderate drought on leaves, four tomato accessions from MAGIC TOM populations were selected on the basis of their differences in fruit size and were grown in a glasshouse under control and water deficit conditions. Drought affected stomatal conductance more in large fruit genotypes compared to cherry genotypes and this could be related to higher abscisic acid (ABA) leaf content. Compared to large fruits, cherry tomato genotypes coped better with water stress by reducing leaf area and maintaining photochemical efficiency as important adaptive responses. Accumulation of soluble sugars in the cherry genotypes and organic acid in the leaves of the larger fruit genotypes indicated their role in the osmoregulation and the continuum of source/sink gradient under stress conditions. Long-term moderate drought induced upregulation of NCED gene in all four genotypes that was associated with ABA production. The increase in the expression of ZEP gene was found only in the LA1420 cherry genotype and indicated its possible role in the protection against photooxidative stress induced by prolonged water stress. In addition, upregulation of the APX genes, higher accumulation of vitamin C and total antioxidant capacity in cherry genotype leaves highlighted their greater adaptive response against long-term drought stress compared to larger fruit genotypes that could also reflect at fruit level. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01102-2.

20.
PLoS One ; 15(12): e0241097, 2020.
Article En | MEDLINE | ID: mdl-33382687

Clinical manifestations of SARS-CoV-2 infection range from mild to critically severe. The aim of the study was to highlight the immunological events associated with the severity of SARS-CoV-2 infection, with an emphasis on cells of innate immunity. Thirty COVID-19 patients with mild/moderate symptoms and 27 patients with severe/critically severe symptoms were recruited from the Clinical Center of Kragujevac during April 2020. Flow cytometric analysis was performed to reveal phenotypic and functional alterations of peripheral blood cells and to correlate them with the severity of the disease. In severe cases, the number of T and B lymphocytes, dendritic cells, NK cells, and HLA-DR-expressing cells was drastically decreased. In the monocyte population proportion between certain subsets was disturbed and cells coexpressing markers of M1 and M2 monocytes were found in intermediate and non-classical subsets. In mild cases decline in lymphocyte number was less pronounced and innate immunity was preserved as indicated by an increased number of myeloid and activated dendritic cells, NK cells that expressed activation marker at the same level as in control and by low expression of M2 marker in monocyte population. In patients with severe disease, both innate and adoptive immunity are devastated, while in patients with mild symptoms decline in lymphocyte number is lesser, and the innate immunity is preserved.


Adaptive Immunity , COVID-19/immunology , Dendritic Cells/immunology , Immunity, Innate , Monocytes/immunology , SARS-CoV-2/immunology , Adult , Aged , Aged, 80 and over , Antigens, Differentiation/immunology , COVID-19/pathology , Dendritic Cells/pathology , Female , Flow Cytometry , HLA-DR Antigens/immunology , Humans , Killer Cells, Natural/immunology , Killer Cells, Natural/pathology , Male , Middle Aged , Monocytes/pathology
...