Click and Detect: Versatile Ampicillin Aptasensor Enabled by Click Chemistry on a Graphene-Alkyne Derivative.

Tackling the current problem of antimicrobial resistance (AMR) requires fast, inexpensive, and effective methods for controlling and detecting antibiotics in diverse samples at the point of interest. Cost-effective, disposable, point-of-care electrochemical biosensors are a particularly attractive option. However, there is a need for conductive and versatile carbon-based materials and inks that enable effective bioconjugation under mild conditions for the development of robust, sensitive, and selective devices. This work describes a simple and fast methodology to construct an aptasensor based on a novel graphene derivative equipped with alkyne groups prepared via fluorographene chemistry. Using click chemistry, an aptamer is immobilized and used as a successful platform for the selective determination of ampicillin in real samples in the presence of interfering molecules. The electrochemical aptasensor displayed a detection limit of 1.36 nM, high selectivity among other antibiotics, the storage stability of 4 weeks, and is effective in real samples. Additionally, structural and docking simulations of the aptamer shed light on the ampicillin binding mechanism. The versatility of this platform opens up wide possibilities for constructing a new class of aptasensor based on disposable screen-printed carbon electrodes usable in point-of-care devices.

Hypercapnic respiratory failure - review.

This review summarizes the issue of acute hypercapnic respiratory failure. Acute respiratory failure is a condition in which the respiratory system is unable to fulfill its basic function, i.e. enriching the blood with oxygen and excreting carbon dioxide. Chronologically, we divide it into acute and chronic, and according to the manifestation into hypoxemic or hypoxemic with hypercapnia. Multiple factors, such as reduced ventilation and increased dead space, contribute to the development of hypoxemic-hypercapnic (global) respiratory failure. Both the patient's clinical presentation and laboratory examination of blood gases and acid-base balance (preferably from arterial blood) are used for diagnosis. In the absence of contraindications, non-invasive ventilation is used to establish normocapnia.

The use of extracorporeal membrane oxygenation in the treatment of critical course of pneumonia.

Extracorporeal membrane oxygenation is the highest form of resuscitation care in management of patients with respiratory failure. In the case of acute respiratory distress syndrome, the veno-venous setting is more often used. ECMO support enables, in case of lung function failure, to obtain the necessary time for the onset of the causal treatment effect or is used as a bridge to transplantation Mortality of the patients varies according to the underlying cause and presence of risk factors (e.g., age, complications or comorbid diseases). The onset of the COVID-19 pandemic has led to a significant increase in the need for ECMO. The quality of life of patients after ECMO is significantly reduced, but most patients do not experience permanent disability.

[Pulmonary complications following COVID-19 infection].

In the relatively short period of time since December 2019, hundreds of millions of people globally have been infected with SARS-CoV-2, irrespective of their age, gender or ethnicity. Over that time, numerous mutations of various degrees of virulence and pathogenicity have occurred. The course of COVID-19 infection, an acute disease caused by the virus, is rather varied, ranging from asymptomatic or symptoms of common viral respiratory diseases to critical, with multiorgan failure and high mortality in high-risk patients. The overall mortality of the disease is 1-2 %. Unlike other viral respiratory diseases, this infection is often associated with frequent and rather diverse clinical manifestations developing after the acute phase of the infection, that is, more than 28 days after its onset. These complications are observed in both individuals with mild illness treated at home and inpatients with severe to critical illness. They develop both early after acute infection and some time after recovering from the disease. This rather heterogeneous group of pathologies may affect various organs and organ systems, with respiratory tract involvement being the most common and one of the most serious complications. Severe respiratory post-COVID-19 complications often include respiratory tract infections, in particular pneumonia.

[Respiratory manifestations of post-COVID syndrome].

Overcoming infection with coronavirus disease 2019 (COVID-19) can lead to the persistence of various symptoms in some patients. The complex of symptoms causally related to severe acute respiratory coronavirus 2 infection is called post-COVID syndrome. One of the most common respiratory complications is pulmonary fibrosis, especially after critical course of the disease. In some patients, however, only the peripheral airways are affected by the air-trapping seen on high-resolution computed tomography scans. Less common respiratory complications include sarcoidosis and pneumatoceles. This narrative review summarizes current knowledge about pulmonary involvement as part of post-COVID syndrome.

Chronic lung diseases and sleep.

Sleep is vitally important part of our life. Its quality and quantity influence all physiological processes in our organism. The relationship between the lung diseases and sleep is bidirectional - the lack of quality sleep worsens the compensation and the course of the diseases and in the same time chronic lung diseases are negatively affecting sleep quality. The coexistence of the sleep disordered breathing and lung disorders is another important issue to discuss. In case of chronic obstructive pulmonary disease the overlap with sleep disordered breathing is characterized by higher prevalence of hypercapnia and overall worse prognosis. Moreover, there is a growing body of evidence about possible links of sleep disordered breathing to lung fibrosis and tumors. The complex healthcare in patients with respiratory diseases should not omit sleep examination.

Antibiotic treatment issues in patients with COVID-19.

The COVID-19 pandemic may increase the current threat of antimicrobial resistance and exacerbate another, rather silent, pandemic posed by the increasing frequency of multidrug-resistant bacterial pathogens and the associated potential for loss of effective antibiotics. Antibiotic treatment has often been used in patients hospitalized for COVID-19 due to concerns about possible bacterial co-infection, as confirmed by previous experience with viral respiratory infections such as H1N1 influenza, SARS and MERS. Concerns or unknowns related to the COVID-19 pandemic have also affected physicians behavior, including the use of antibiotics. However, the high rate of antibiotic use in patients, especially those with mild to moderate COVID-19 disease, is inconsistent with the actual incidence of bacterial co-infections and/or secondary respiratory infections. Thus, it is clear that a careful assessment of the role of antibiotic treatment in patients hospitalized for COVID-19 is required. According to the current WHO recommendation, the application of antibiotics is especially suitable for patients with severe/critical degree of respiratory insufficiency requiring intensive oxygen therapy, artificial lung ventilation or support by extracorporeal membrane oxygenation.

Bilateral multiple pneumatocele as a rare late complication of COVID-19 pneumonia.

Pneumatocele is a cavity, which may develop rarely as a complication of pneumonia. It is more common in patients requiring ventilation support. After COVID-19 pneumonia, there are only several case reports described. Our case report is about a male patient without any serious commorbities. The patient had bilateral multiple pneumatocele which have formed in postacute phase of moderate course of COVID-19. Other possible causes have been exluded by a complex examination. During the follow-up there was a clear gradual spontaneous resorption of the finding. The patient is still in very good clinical condition.

[Diagnostics and treatment of community-acquired pneumonia - simplicity is the key to success]. / Diagnostika a lécba komunitní pneumonie - v jednoduchosti je klíc k úspechu.

Pneumonia is the most wide-spread infectious disease and requires unrelenting attention. It is defined as an acute inflammatory disease affecting pulmonary alveoli, respiratory bronchioles and the pulmonary interstitium. In recent years we have seen the endeavour to rationalize the approach to pneumonias and utilize the current methods of administering effective antibiotics to reduce occurrence of complications, limit the number of hospitalizations and shorten the length of treatment. With the awareness of all the potential agents it is empiric therapy which predominates, being supported by the knowledge of a regional epidemiological situation, good diagnosing and experience of rational antibiotic treatment. Very important is categorization of patients based on possible risks of complications and mortality. Considering that an appropriate form of treatment is chosen: outpatient care or hospitalization.Key words: community-acquired pneumonia - treatment criteria - prognosis - occurrence.

[Hospital-acquired pneumonias]. / Nozokomiální pneumonie.

Nosocomial infections are a common complication of hospital care. Hospital-acquired (HAP) pneumonia is one of the most common nosocomial infections and it is the most dangerous in terms of mortality. The problem is mainly selected hospital bacterial strains with rising antibiotic resistance. Diagnosis of the cause of pneumonia is difficult and often does not lead to a positive result. Management is complex and is based on timely and appropriate empirical antibiotic treatment. Local and extrapulmonary complications are relatively common and they increase morbidity and mortality. Prognosis of the HAP is often unfavorable, especially in the elderly and polymorbid individuals.Key words: complications - etiology - hospital-acquired pneumonia - management.

[The complications after lung transplantation]. / Komplikace po transplantaci plic.

Lung transplantation (LuTx) is an important treatment for a selected group of patients in the terminal stage of a number of lung diseases, which can bring them a significant improvement in quality of life and long-term survival. Nowadays a perioperative period is not significant limitation for patient survival due to the development of transplant surgery, but the period of months to years after LuTx is crucial for survival. The post-transplant period is very complicated for LuTx patients due to a special treatment regimen, special medication, especially immunosuppressive drugs and the possibility of many complications, whether early or late or acute or chronic. These complications can be divided into several groups. These are rejections, infections, tumors, non-infectious pulmonary complications, and extrapulmonary complications. This is a very wide range of diverse states and to cope with them, it is necessary, apart from good patient co-operation, to team together with specialists in many fields of medicine. But the reward is the satisfaction, good quality of life and long-term survival of transplanted patients.Key words: infection - lung transplantation - rejection - tumours.

Advanced Sensing of Antibiotics with Magnetic Gold Nanocomposite: Electrochemical Detection of Chloramphenicol.

The sensing and accurate determination of antibiotics in various environments represents a big challenge, mainly owing to their widespread use in medicine, veterinary practice, and other fields. Therefore, a new, simple electrochemical sensor for the detection of antibiotic chloramphenicol (CAP) has been developed in this work. The amplification strategy of the sensor is based on the application of magnetite nanostructures stabilized with carboxymethyl cellulose (Fe3 O4 -CMC) and decorated with nanometer-sized Au nanoparticles (NPs) (Fe3 O4 -CMC@Au). In this case, CMC serves as a stabilizing agent, preventing the aggregation of Fe3 O4 NPs, and hence, enabling the kinetic barrier for electron transport to be overcome, and the Au NPs serve as an electron-conducting tunnel for better electron transport. As a proof of concept, the developed nanosensor is used for the detection of CAP in human urine samples, giving a recovery value of around 97 %, which indicates the high accuracy of the as-prepared nanosensor.

Colloidal Surface Active Maghemite Nanoparticles for Biologically Safe Cr(VI) Remediation: from Core-Shell Nanostructures to Pilot Plant Development.

The present study is aimed at the exploration of achievable improvements for Cr(VI) ex situ and in situ water remediation by using novel naked colloidal maghemite (γ-Fe2 O3 ) nanoparticles (surface active maghemite nanoparticles, SAMNs). The reliability of SAMNs for Cr(VI) binding and removal was demonstrated, and SAMN@Cr(VI) complex was characterized, as well as the covalent nature of the absorption was unequivocally proved. SAMNs were structurally and magnetically well conserved after Cr(VI) binding. Thus, in consideration of their affinity for Cr(VI) , SAMNs were exploited in a biological model system, mimicking a real in situ application. The assay evidenced a progressive reduction of revertant colonies of Salmonella typhimurium TA100 strain, as maghemite nanoparticles concentration increased, till the complete suppression of Cr(VI) mutagen effect. Finally, an automatic modular pilot system for continuous magnetic removal and recovery of Cr(VI) from water is proposed. SAMNs, thanks to their colloidal, binding, and catalytic properties, represent a promising tool as a reliable nanomaterial for water remediation by Cr(VI) .

Ternary Hybrid γ-Fe2 O3 /Cr(VI) /Amine Oxidase Nanostructure for Electrochemical Sensing: Application for Polyamine Detection in Tumor Tissue.

Dichromate binds to surface-active maghemite nanoparticles (SAMNs) to form a stable core-shell nanostructures (SAMN@Cr(VI) ). The hybrid was characterized by Mössbauer spectroscopy, high-angle annular dark-field imaging, electron energy-loss spectroscopy, and electrochemical techniques, which revealed a strong interaction of dichromate with the nanoparticle surface. Electrochemical characterization showed lower charge-transfer resistance, better electrochemical performance, and more reversible electrochemical behavior with respect to naked SAMNs. Moreover, SAMN@Cr(VI) is an excellent electrocatalyst for hydrogen peroxide reduction. Furthermore, an enzyme, namely, bovine serum amine oxidase (BSAO: EC 1.4.3.6), was immobilized on SAMN@Cr(VI) by self-assembly to give a ternary hybrid nanostructured catalyst for polyamine oxidation (SAMN@Cr(VI) -BSAO). SAMN@Cr(VI) -BSAO was applied for the development of a reagentless, fast, inexpensive, and interference-free polyamine biosensor, which was successfully exploited for the discrimination of tumorous tissue from healthy tissue in human crude liver extracts.

Electrocatalytic Nanostructured Ferric Tannates: Characterization and Application of a Polyphenol Nanosensor.

A novel core-shell hybrid nanomaterial composed of peculiar maghemite nanoparticles (surface-active maghemite nanoparticles (SAMNs)) as the core and tannic acid (TA) as the shell was developed by self-assembly of ferric tannates onto the surface of SAMNs by simple incubation in water. The hybrid nanomaterial (SAMN@TA) was characterized by using UV/Vis, FTIR, and Mössbauer spectroscopies, magnetization measurements, and X-ray powder diffraction, which provide evidence of a drastic reorganization of the iron oxide surface upon reaction with TA and the formation of an outer shell that consists of a cross-linked network of ferric tannates. According to a Langmuir isotherm analysis, SAMN@TA offers one of most stable iron complexes of TA reported in the literature to date. Moreover, SAMN@TA was characterized by using electrical impedance spectroscopy, voltammetry, and chronoamperometry. The nanostructured ferric tannate interface showed improved conductivity and selective electrocatalytic activity toward the oxidation of polyphenols. Finally, a carbon-paste electrode modified with SAMN@TA was used for the determination of polyphenols in blueberry extracts by square-wave voltammetry.

[Prolonged culture in a humid chamber increases the yields of pathogenic bacteria from the respiratory tract samples of patients suffering from cystic fibrosis].

Current standards of care for cystic fibrosis (CF) patients lack unequivocal recommendations concerning the duration of primary culture of bacteriological samples. With the exception of Burkholderia cepacia (5 days), the minimum recommended duration of primary culture varies between 48 and 72 hours. Our aim was to evaluate the effect of an extended 10-day period of primary culture in a humid chamber in samples acquired from the respiratory tract of patients suffering from CF. Compared to standard culture, prolonged culture in a humid chamber yielded 1.85 times more isolates of pathogenic species in pharyngeal swabs (76 versus 41 isolates) and 1.4 times more isolates in sputum samples (116 versus 82), but only 1.14 times more isolates in nasal swabs (25 versus 22). Prolonged culture was most beneficial for Achromobacter spp. (6 versus 0), Stenotrophomonas maltophilia (16 versus 5) and Pseudomonas aeruginosa (69 versus 49), whereas there was little or no benefit at all for Staphylococcus aureus (87 versus 73) and Moraxella catarrhalis (10 versus 10). Therefore, prolonged culture in a humid chamber may definitely be recommended for pharyngeal swabs and sputum samples obtained from patients suffering from CF to achieve the maximum recovery rate of pathogenic bacteria, in particular non-fermenting Gram-negative rods.

[Diagnostics of cystic fibrosis in adults]. / Diagnostika cystické fibrózy u dospelých.

INTRODUCTION: There is an increasing number of cystic fibrosis (CF) patients with the diagnosis established in adulthood worldwide. AIM: To give an overview of our experience with the diagnostics of CF in adulthood in the Czech Republic. METHODS: CF patients with the diagnosis determined at the age 18 years during 2000-2014 period were selected from the Czech Registry of CF (www.cfregistr.cz). Demographic and clinical data were reported from medi-cal records at the time of diagnosis and as of 31st December 2014. Only those with two CF causing mutation or with one CF causing mutation together with sweat chloride concentration > 60 mmol/l were included in the study. The clinical presentation was compared with a control group consisting of homozygous F508del patients with the diagnosis established in childhood. RESULTS: 23 patients (16 men and 7 women) with the diagnosis determined at a mean age of 32.9 ± 8.5 years were included in the study. Presenting symptoms included bronchiectasis and/or haemoptysis in 12 cases, obstructive azoospermia in 7 cases and recurrent pancreatitis in 4 cases. When compared with the control group, the patients had higher age (38.6 ± 8.3 vs. 28.3 ± 4.7 years; p < 0.001), a lower concentration of sweat chloride (62 ± 23 vs. 90 ± 12 mmol/l; p < 0.001), less frequent airway infections with Pseudomonas aeruginosa and/or Burkholderia cepacia complex (4 vs. 12; p = 0.029), bronchiectasis (14 vs. 23; p = 0.001), exocrine pancreatic insufficiency (1 vs. 23; p < 0.001) and therapy with insulin (1 vs. 9; p = 0.01); on the contrary, pancreatitis was more frequent (6 vs. 0; p = 0.022). CONCLUSION: Diagnosis of CF in adults should be considered in those with corresponding symptoms in respiratory, digestive and reproductive tract. Clinical presentation differs from classical CF in many parameters. KEY WORDS: adults - cystic fibrosis - diagnostics.

[Validity comparison of various biological samples from lower airway and their contribution for the detection of nosocomial pneumonia etiological agents]. / Porovnání validity ruzných vzorku biologického material z dýchacích cest a jejich prínosu v detekci puvodcu nozokomiální pneumonie.

BACKGROUND: The aim of the study was to compare the validity of bronchial secretion sampling and bronchoscopy-assisted protected specimen brushing (PSB) in patients with hospital-acquired pneumonia (HAP). MATERIALS AND METHODS: In patients with HAP, bronchial secretion samples (aspiration of lower airway secretions from an orotracheal tube with a suctioning catheter) and PSB (bronchoscopy-assisted sampling from the most affected area of the lung, verified by CT scan) were taken at the same time. Both samples were processed by semiquantitative routine microbiological techniques. Identification of microorganisms was performed by standard microbiological techniques using the MALDI-TOF automated system. For similarity or identity determination of bacterial isolates from bronchial secretion sampling and PSB, pulsed-field gel electrophoresis was used. RESULTS: Thirty patients were enrolled into the study. Thirty pairs of bronchial secretion samples and PSB samples were obtained and processed. The samples were positive in 23 patients (77 %) and 15 patients (50 %), respectively. In 15 cases, the same pathogen was determined in both samples, and in all those cases, the isolates were genetically identical. CONCLUSION: The results of the study show that bronchial secretion samples analysis enabled identification of all pathogens that were identified by PSB. Given the high sensitivity of the bronchial secretion aspiration technique and genetic identity of isolates in both samples, bronchial secretion sampling may be recommended for determining HAP etiological agents as the samples are much easier to obtain from patients.

[Utility of Pneumonia Severity Index in hospitalized patients with pneumonia in intensive respiratory care units]. / Význam Pneumonia Severity Index u pacientu s pneumonií hospitalizovaných na jednotce intenzivní pneumologické péce.

INTRODUCTION: The aim of this study was to evaluate the prognostic value of Pneumonia Severity Index (PSI) for prediction of 30-day mortality in patients admitted to intensive care unit (ICU) for community-acquired pneumonia (CAP). In patients with CAP, comorbidities, complications, and physical, laboratory, radiological and microbiological findings were evaluated relative to their prognosis. PATIENT AND METHODS: In the study, 197 patients with CAP, hospitalised at ICU of Department of Respiratory Medicine, University Hospital Olomouc between 2008 and 2012, were enrolled. Risk factors according to PSI were assessed in all patients. RESULTS: In the studied cohort of patients with CAP, mean values of PSI were 115.4 ± SD 30.4 points. Overall, 29 patients (14.7 %) deceased. When comparing deceased and survived patients, statistically significant differences were found in PSI (mean ± SD: 137.4 ± 26.1 vs 111.7 ± 29.6 points, p < 0.0001), age (mean ± SD: 76.3 ± 12.9 vs 65.5 ± 14.7 years, p < 0.0001), incidence of heart diseases (86.2 % vs 67.3 %, p = 0.04) and ischaemic heart disease (58.6 % vs 38.7 %, p = 0.04). Assessment of physical and laboratory findings showed that deceased patients had significantly increased incidence of tachycardia above 90/min (51.7 % vs 27.4 %, p = 0.01), tachypnoe above 30/min (37.9 % vs 13.7 %, p = 0.001) and acidosis with pH < 7.35 (27.6 % vs 8.9 %, p = 0.004) comparing to survived patients. No significant correlation between PSI and the length of hospitalisation in survived patients was observed. In patients with Staphylococcus sp. and Klebsiella pneumoniae infection, longer hospitalisation period was observed. Comparison of other parameters such as comorbidities, physical and laboratory findings, and pathogens showed no significant differences when comparing deceased to survived patients. CONCLUSION: Our study showed that PSI represents an important predictor of 30-day mortality in patients with CAP at ICU, but does not correlate neither with the length of hospitalisation nor with particular pathogens. Independent negative prognostic factors in CAP were age, incidence of heart diseases (most importantly ischaemic heart disease), tachycardia, tachypnoe and acidosis. Staphylococcus sp. and Klebsiella pneumoniae infection led to longer hospitalisation period. All these factors point out the need for increased care in CAP patients.

[Closed pleural biopsy in the diagnostics of malignant pleural involvement]. / Necílená biopsie pleury v diagnostice maligního pleurálního výpotku - nase zkusenosti za posledních 15 let.

INTRODUCTION: Pleural effusion is a frequent reason for a pulmonologist´s investigation. The cornerstone is to distinguish transudative pleural effusion from exudative pleural effusion. In the case of the exudative pleural effusion the next step is detection of malignant etiology of pleural effusion. We have a variety of any non-invasive or invasive examinations. The pleural biopsy is one of the most important methods for diagnostics of malignant pleural effusion. MATERIAL AND METHODS: Two hundred and twenty-two closed pleural biopsies (CPB) were performed in 208 patients with pleural effusion, where the cytologic examination of pleural fluid was negative. The authors evaluated the value of CPB for the diagnosis of malignant pleural involvement. RESULTS AND CONCLUSION: Total sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 63.1%, 100%, 73.9%, 100% and 52.8%, but in the group of mesotheliomas these results were 59.1%, 100%, 79.4%, 100% and 70.7%. The incidence of complications and representative sampling of the pleura was mentioned. The authors compared the diagnostic value and the incidence of complications of various diagnostic methods in malignant pleural involvement by data in the literature.