The role of thoracic surgery in the management of complicated acute and post-acute COVID-19 pneumonia (PASC).

INTRODUCTION: COVID-19 is considered a respiratory virosis in its classic form, although it may present with heterogeneous symptoms. Thoracic complications occur in a small percentage of patients. Our objective was to evaluate existing experience with this disease and its thoracic manifestations and to determine the real-world status of care of these patients. METHODS: This study is a retrospective, single-institution analysis of a group of patients hospitalized with acute and post-acute COVID-19 pneumonia at Thomayer Hospital in Prague in the period from December 2020 to March 2022 and indicated for a thoracic surgical procedure. RESULTS: During the peak of COVID-19 pandemic, a thoracic intervention was performed in 46 admitted patients. Thoracic drainage (due to pneumothorax in 18 cases, fluidothorax in 3 cases, CT-guided lung abscess drainage in 2 cases, and CT-guided pneumatocele drainage in 2 cases) were the most common thoracic surgical procedures. Pleurectomy/decortication surgery was done in 10 cases. Additionally, 12 lung parenchyma-sparing resections were performed, while lobectomy was required in 2 cases. Resection of postintubation tracheal stenosis due to a severe course of COVID-19 pneumonia was indicated in 2 patients. CONCLUSION: Even mild COVID-19 may cause a considerable morphological a functional alteration of the respiratory system. The most common complications of COVID-19 pneumonia that require a thoracic surgical intervention include pathologies associated with an air leak and accumulation of air (pneumothorax, pneumomediastinum and subcutaneous emphysema). The development of pulmonary necrosis, symptomatic bronchiectasis, pneumatocele, and bullous-fibrotic formations may result in pneumothorax, hemothorax or thoracic empyema in sporadic cases. An early thoracic surgical intervention to treat thoracic complications of COVID-19 pneumonia can improve the survival of COVID-19 patients.

Negative pressure wound therapy updates for 2021.

Negative pressure wound therapy (NPWT) has been used in clinical practice for 25 years. Worldwide, it has been used to treat more than 10 million wounds. The repertoire of NPWT procedures is still growing. This originally simple procedure entails a number of pitfalls and limits, and full utilisation of the micro-deformation potential of NPWT depends on many key details. We present the pathophysiology, effects and forms of NPWT use including our own experience, tips and a proposal for the use of NPWT during the COVID-19 pandemic.

Penetrating abdominal trauma - selected case reports.

We present 3 case-reports with penetrating abdominal injury from our practice in this article. An urgent laparotomy was performed in all cases because of haemodynamic instability or the mechanism of injury. Penetrative abdominal traumas are associated with a high risk of life-threatening intra-abdominal injuries, require urgent revision and are often accompanied by postoperative infections of the peritoneal cavity. In recent years, there has been a growing tendency towards mini-invasive approaches or even non-operative treatment. This trend is particularly evident in the United States of America, where doctors experience a higher number of penetrating injuries compared to the prevalent blunt force trauma in Europe. The authors describe the need to follow all recommended procedures in the pre-hospital and hospital phases of treatment of these patients and compare them with recent literature. Key words: penetrating abdominal trauma.

Regenerative abilities of a nanofiber wound dressing based on polylactide.

INTRODUCTION: The development of an ideal dressing for wound healing remains an unresolved issue. Thanks to the development of electrospinning technology, polymers in the form of nanofibers have come to the forefront of research interest. A modern and very promising dressing material is a “nonwoven” based on nanofibers of the synthetic polymer polylactide (PLA). The aim of this work was to assess the regenerative abilities of PLA in a standardized wound in a porcine model and compare our results to the literature data. METHODS: We applied PLA-based nanofiber dressings to the standardized wounds created in the porcine model. On the third, tenth, seventeenth and twenty-fourth days after the formation of the defect, we changed the wound dressing while taking a tissue sample for histopathological examination. We continuously monitored serum levels of acute phase proteins. RESULTS: PLA stimulated an inflammatory response. From the third day, the thickness of the fibrin layer with granulocytes increased. It reached its maximum values on the tenth day (mean 340 μm); at the same time the level of serum amyloid A, as a marker of inflammation, culminated. The individual phases of healing intertwined. The highest thickness values of the granulation tissue with cellular connective tissue (diameter 8463 μm) were reached on the seventeenth day. On the twenty-fourth day, the defects were healed macroscopically with a mean reepithelialization layer of 9913 μm. CONCLUSION: PLA-based nanofiber dressing potentiates the inflammatory, proliferative and reepithelialization phases of healing. Its structure perfectly mimics the extracellular matrix and serves as a 3D network for the growth and interaction of cellular elements. In addition to biocompatibility, PLA has a unique ability of two-phase biodegradation. It is a promising material for industrial production of dressing materials. Most of the available studies were performed in vitro. In vivo comparative studies approximating the use of PLA to daily practice are still missing.

High infection rate of bank voles (Myodes glareolus) with Puumala virus is associated with a winter outbreak of haemorrhagic fever with renal syndrome in Croatia.

An outbreak of haemorrhagic fever with renal syndrome (HFRS) started on Medvednica mountain near Zagreb in January 2012. In order to detect the aetiological agent of the disease in small rodents and to make the link with the human outbreak, rodents were trapped at four different altitudes. Using nested RT-PCR, Puumala virus (PUUV) RNA was detected in 41/53 (77·4%) bank voles (Myodes glareolus) and Dobrava virus (DOBV) RNA was found in 6/61 (9·8%) yellow-necked mice (Apodemus flavicollis). Sequence analysis of a 341-nucleotide region of the PUUV S segment, obtained from all infected bank voles and five HFRS patients, showed 98·8-100% sequence similarity, indicating that the patients were probably exposed to PUUV on Medvednica mountain. A very large bank-vole population combined with an extremely high infection rate of PUUV was responsible for this unusual winter outbreak of HFRS in Croatia.

Reflects the coat protein variability of apple mosaic virus host preference?

Apple mosaic virus (ApMV) is a widespread ssRNA virus which infects diverse species of Rosales. The phylogenetic analysis of complete capsid protein gene of the largest set of ApMV isolates discriminated two main clusters of isolates: one cluster correlates with Maloideae hosts and Trebouxia lichen algae hosts; a second with hop, Prunus, and other woody tree hosts. No correlation was found between clusters and geographic origin of virus isolates, and positive selection hypothesis in distinct hosts was not confirmed: in all virus populations, purifying selection had occurred. GGT→AAT substitution resulted in Gly→Asn change inside the zinc-finger motif in the capsid protein was revealed specific for discrimination of the clusters and we hypothesise that could influence the host preference.

[The benefits of centralization of care for patients with acute upper gastrointestinal bleeding]. / Prínos centralizace péce o pacienty s akutním krvácením do horního trávicího traktu.

INTRODUCTION: Acute upper gastrointestinal bleeding still remains one of the serious conditions that require a rapid diagnostic and therapeutic intervention. Such procedure is highly dependent on good interdisciplinary cooperation, which, when centralized, may positively influence mortality and economic costs. OBJECTIVE: To determine the benefits of centralization of care provided to patients with acute bleeding in the upper gastrointestinal tract. PATIENTS AND METHODS: A total of 632 patients with acute bleeding were enrolled in the study at two different health-care establishments of the same type, however with a different organisation of care. We have evaluated the influence of the organisation of care on the length of hospitalization stay, mortality and economic costs. RESULTS: Centralized treatment significantly shortens the interval from hospital admission to endoscopic examination and leads to a reduction in mortality, although not statistically significant. On the other hand, it does not affect the length of hospitalization, the distribution of patients between internal and surgical departments, and provides no guarantee of lower economic costs. Many other factors play an important role in that respect. It seems, that the importance of centralization plays the main role especially in the pre-hospital and early hospital period, when it accelerates and simplifies the diagnostic and therapeutic procedure.

Development of a new peptide-bead coupling method for an all peptide-based Luminex multiplexing assay for detection of Plasmodium falciparum antibody responses.

Using a recombinant protein antigen for antibody testing shows a sum of antibody responses to multiple different immune epitopes existing in the protein antigen. In contrast, the antibody testing to an immunogenic peptide epitope reflects a singular antibody response to the individual peptide epitope. Therefore, using a panel of peptide epitopes provides an advantage for profiling multiple singular antibody responses with potential to estimate recent malaria exposure in human infections. However, transitioning from malaria immune epitope peptide-based ELISA to an all peptide bead-based multiplex Luminex assay presents some challenges including variation in the ability of different peptides to bind beads. The aim of this study was to develop a peptide coupling method while demonstrating the utility of these peptide epitopes from multiple stage antigens of Plasmodium falciparum for measuring antibodies. Successful coupling of peptide epitopes to beads followed three steps: 1) development of a peptide tag appended to the C-terminus of each peptide epitope consisting of beta-alanine-lysine (x 4)--cysteine, 2) bead modification with a high concentration of adipic acid dihydrazide, and 3) use of the peptide epitope as a blocker in place of the traditional choice, bovine serum albumin (BSA). This new method was used to couple 12 peptide epitopes from multiple stage specific antigens of P. falciparum, 1 Anopheles mosquito salivary gland peptide, and 1 Epstein-Barr virus peptide as an assay control. The new method was applied to testing of IgG in pooled samples from 30 individuals with previously repeated malaria exposure in western Kenya and IgM and IgG in samples from 37 U.S. travelers with recent exposure to malaria. The new peptide-bead coupling method and subsequent multiplex Luminex assay showed reliable detection of IgG to all 14 peptides in Kenyan samples. Among 37 samples from U.S. travelers recently diagnosed with malaria, IgM and IgG to the peptide epitopes were detected with high sensitivity and variation. Overall, the U.S. travelers had a much lower positivity rates of IgM than IgG to different peptide epitopes, ranging from a high of 62.2% positive for one epitope to a low of only 5.4% positive for another epitope. In contrast, the travelers had IgG positive rates from 97.3% to 91.9% to various peptide epitopes. Based on the different distribution in IgM and IgG positivity to overall number of peptide epitopes and to the number of pre-erythrocytic, erythrocytic, gametocytic, and salivary stage epitopes at the individual level, four distinct patterns of IgM and IgG responses among the 37 samples from US travelers were observed. Independent peptide-bead coupling and antibody level readout between two different instruments also showed comparable results. Overall, this new coupling method resolves the peptide-bead coupling challenge, is reproducible, and can be applied to any other immunogenic peptide epitopes. The resulting all peptide bead-based multiplex Luminex assay can be expanded to include other peptide epitopes of P. falciparum, different malaria species, or other diseases for surveillance, either in US travelers or endemic areas.

The effect of detergents on trimeric G-protein activity in isolated plasma membranes from rat brain cortex: correlation with studies of DPH and Laurdan fluorescence.

The effect of non-ionic detergents on baclofen (GABAB-R agonist)-stimulated G-protein activity was measured as a [(35)S]GTPgammaS binding assay in the plasma membranes (PM) isolated from the brain tissue. The effect was clearly biphasic--a decrease in the activity was followed by an activation maximum and finally, at high concentrations, drastic inhibition of the G-protein activity was noticed. Contrarily, specific radioligand binding to GABAB-receptor was inhibited in the whole range of detergent concentrations step by step, i.e. it was strictly monophasic. The magnitude of both detergent effects was decreased in the same order of potency: Brij58>Triton X-100>Digitonin. The identical order was found when comparing detergents ability to alter fluorescence anisotropy of the membrane probe 1,6-diphenyl-1,3,5-hexatriene (rDPH) incorporated into the hydrophobic PM interior. Decrease of rDPH, in the order of Brij58>Triton X-100>Digitonin, was reflected as decrease of the S-order parameter and rotation correlation time phi paralleled by an increase of diffusion wobbling constant Dw (analysis by time-resolved fluorescence according to "wobble-in-cone" model). The influence of the detergents on the membrane organization at the polar headgroup region was characterized by Laurdan generalized polarization (GP). As before, the effect of detergents on GP parameters proceeded in the order: Brij58>Triton X-100>Digitonin.

Systematic study of Mn-doping trends in optical properties of (Ga,Mn)As.

We report on a systematic study of optical properties of (Ga,Mn)As epilayers spanning the wide range of accessible Mn(Ga) dopings. The material synthesis was optimized for each nominal Mn doping in order to obtain films which are as close as possible to uniform uncompensated (Ga,Mn)As mixed crystals. We observe a broad maximum in the mid-infrared absorption spectra whose position exhibits a prevailing blueshift for increasing Mn doping. In the visible range, a peak in the magnetic circular dichroism also shifts with increasing Mn doping. The results are consistent with the description of ferromagnetic (Ga,Mn)As based on the microscopic valence band theory. They also imply that opposite trends seen previously in the optical data on a limited number of samples are not generic and cannot serve as an experimental basis for postulating the impurity band model of ferromagnetic (Ga,Mn)As.

The electrocardiographic Holter monitoring in experimental veterinary practice.

The long-term electrocardiographic recording with retrospective evaluation (Holter system) has been widely used not only in cardiology, but also in other disciplines of internal medicine and in pharmaceutical research. The Holter system can be used in mini-pig, sheep, dog, cat, rabbit, ferret, and rat. In this paper hardware, software, and anesthesia requirements are summarized with respect to the experimental work with various species. As the Holter systems work in bipolar mode, the use of bipolar leads in sagittal and transversal planes has been proved to be the most appropriate because of large amplitude of QRS complex and uncomplicated consequent automatic analysis of the record. In conclusion, Holter electrocardiography represents a simple and applicable method for monitoring the electrical activity of the heart in small animals' experimental studies.

[A different view of acute upper gastrointestinal bleeding in liver cirrhosis patients]. / Jiný pohled na akutní krvácení do horního trávicího traktu u pacientu s jaterní cirhózou.

OBJECTIVES: The study focuses predominantly on non-varicose sources of acute upper gastrointestinal bleeding in liver cirrhosis patients and aims to determine its mortality. METHODS AND SUBJECTS: The prospective examination included 137 liver cirrhosis patients with acute upper GIT bleeding. All the patients underwent an endoscopic examination. In case of multiple findings, defining the bleeding source was based on the specialist's attitude presented as the conclusion of the endoscopic examination. RESULTS: The most frequent causes of acute bleeding included oesophagus varices (57.7%), followed by peptic gastric and duodenal ulcers (18.2%), then portal hypertension gastropathy (9.5%), gastric varices (5.1%), reflux oesophagitis (2.9%), Mallory-Weiss syndrome (2.9%) and erosive gastropathy (1.5%). The endoscopy of the upper digestive tract resulted in a negative diagnosis in not more than 2.2% of patients. The majority of examinations showed multiple findings in the upper digestive tract, each of which could have been a potential cause of bleeding. Mortality in all bleeding cirrhotic patients reached 14.6%, 18.6% of which were related to the varicose type of bleeding and 7.8% to the non-varicose type. CONCLUSION: Portal hypertension led to bleeding (caused by varices and portal hypertension gastropathy) in 72.3% of patients, 62.8% patients suffered from purely varicose bleeding, 37.2% patients from non-varicose bleeding. Mortality was statistically significantly higher on 0.1 level of significance in cases of varicose bleeding in comparison with non-varicose bleeding. An emphasis should be laid on an early and detailed endoscopic examination leading to an appropriate diagnosis and therapy.

Advanced characterization of natural biofilm on nanofiber scaffold.

Nanofiber scaffolds provide numerous advantages over common carriers engineered for microorganisms. The most important advantage is an increased speed of primary surface colonization (up to four times faster), which shortens the time required for the areal biofilm formation and optimum performance of attached microorganisms (higher efficiency of biological activity of up to twice as fast). Image analysis predicts early formation of biofilm even in beginning stages; analysis of biofilm reveals the different structures of bacterial colonies on both scaffolds (higher porosity, size, and number of bacterial colonies on nanofiber's surface). The image analysis correlates well with determinations of dry matter (linear correlation of 0.96) and proteins (linear correlation of 0.89).

The time-course of agonist-induced solubilization of trimeric G(q)alpha/G(11)alpha proteins resolved by two-dimensional electrophoresis.

Prolonged agonist stimulation results in specific transfer of activated Galpha subunits of G(q)alpha/G(11)alpha family from particulate membrane fraction to soluble (cytosol) cell fraction isolated as 250,000 x g supernatant. In this study, we have used 2D electrophoresis for more defined resolution of Galpha subunits of G(q)alpha/G(11)alpha family and followed the time course of solubilization effect. The small signal of soluble G proteins was already detected in control, hormone-unexposed cells. Hormone stimulation resulted in a slow but continuous increase of both intensity and number of immunoreactive signals/spots of these G proteins (10, 30, 60, 120 and 240 min). At longer times of agonist exposure (>2 hours), a marked increase of G(q)alpha/G(11)alpha proteins was detected. The maximal level of soluble G(q)alpha/G(11)alpha proteins was reached after 16 hours of continuous agonist exposure. At this time interval, eight individual immunoreactive signals of G(q)alpha/G(11)alpha proteins could be resolved. The relative proportion among these spots was 15:42:10:11:7:7:2:5. Solubilization of this class of Galpha proteins was thus observed after prolonged agonist stimulation only, induced by ultra high concentration of hormone and in cells expressing a large number of GPCRs. Our data therefore rather indicate tight/persisting binding of G(q)alpha/G(11)alpha proteins to the membrane.

Subcellular redistribution of trimeric G-proteins--potential mechanism of desensitization of hormone response: internalization, solubilization, down-regulation.

Agonist-induced subcellular redistribution of G-protein coupled receptors (GPCR) and of trimeric guanine-nucleotide binding regulatory proteins (G-proteins) represent mechanisms of desensitization of hormone response, which have been studied in our laboratory since 1989. This review brings a short summary of these results and also presents information about related literature data covering at least small part of research carried out in this area. We have also mentioned sodium plus potassium dependent adenosine triphosphatase (Na, K-ATPase) and 3H-ouabain binding as useful reference standard of plasma membrane purity in the brain.

[Effects of mental stress on the health status of the accused during a criminal trial]. / Vliv psychického stresu na zdravotni stav obvineného v prubehu trestního rízení.

A court-sworn medical expert is sometimes authorized to pass a medical judgement, whether an older, from serious diseases suffering accused is able to take part in the criminal trial proceedings. The court-sworn medical expert is required to consider the accused's fitness, his mental and physical ability to appear in court, to understand the trial, to answer the questions of the judge, to defend himself, to put questions and objections against the witness's testimony, etc. Such medical expert's opinion is usually a task for a psychiatrist. Judgement of the ability of the accused to take part in the main court trial is of another character, especially when the accused is suffering from a serious disease, e.g. cardiovascular, pulmonary, gastrointestinal, haematological, tumorous or other. In this case the medical judgement is usually required from a doctor of internal medicine. Nevertheless, this is not an easy task for him. As far as these problems are concerned, the expert gathers only little experience of his own during his juridical practice. Similar cases have been extremely sporadically published in medical or juridical literature and if, then in common sense only. It is evident that the expert must face any possible aggravation of the accused's difficulties. At the same time the expert ought to take care lest the court trial should be inadequately extended and even should prevent the accused's avoidance in the main court trial. This paper tries to determine the basic rules for the court-sworn experts in the branch of internal medicine and would like to facilitate them to judge under which circumstances a seriously ill accused may appear in trial proceedings without exposing him to a serious damage of his health or even endangerment of his life.

Metformin attenuates myocardium dicarbonyl stress induced by chronic hypertriglyceridemia.

Reactive dicarbonyls stimulate production of advanced glycation endproducts, increase oxidative stress and inflammation and contribute to the development of vascular complications. We measured concentrations of dicarbonyls - methylglyoxal (MG), glyoxal (GL) and 3-deoxyglucosone (3-DG) - in the heart and kidney of a model of metabolic syndrome - hereditary hypertriglyceridemic rats (HHTg) and explored its modulation by metformin. Adult HHTg rats were fed a standard diet with or without metformin (300 mg/kg b.w.) and dicarbonyl levels and metabolic parameters were measured. HHTg rats had markedly elevated serum levels of triacylglycerols (p<0.001), FFA (p<0.01) and hepatic triacylglycerols (p<0.001) along with increased concentrations of reactive dicarbonyls in myocardium (MG: p<0.001; GL: p<0.01; 3-DG: p<0.01) and kidney cortex (MG: p<0.01). Metformin treatment significantly reduced reactive dicarbonyls in the myocardium (MG: p<0.05, GL: p<0.05, 3-DG: p<0.01) along with increase of myocardial concentrations of reduced glutathione (p<0.01) and glyoxalase 1 mRNA expression (p<0.05). Metformin did not have any significant effect on dicarbonyls, glutathione or on glyoxalase 1 expression in kidney cortex. Chronically elevated hypertriglyceridemia was associated with increased levels of dicarbonyls in heart and kidney. Beneficial effects of metformin on reactive dicarbonyls and glyoxalase in the heart could contribute to its cardioprotective effects.

Proteomic identification of the wt-p53-regulated tumor cell secretome.

Tumor-stroma interactions play a major role in tumor development, maintenance and progression. Yet little is known on how the genetic alterations that underlie cell transformation elicit cell extrinsic changes modulating heterotypic cell interactions. We hypothesized that these events involve a modification in the complement of secreted proteins by the cell, acting as mediators of intercellular communication. To test this hypothesis, we examined the role of wt-p53, a major tumor suppressor, on the tumor microenvironment through its regulation of secreted factors. Using a combination of 2-DE and cICAT proteomic techniques, we found a total of 111 secreted proteins, 39 of which showed enhanced and 21 inhibited secretion in response to wt-p53 expression. The majority of these were not direct targets of p53 transcription factor activity, suggesting a novel role for wt-p53 in the control of intracellular protein trafficking and/or secreted protein stability. Evidence for p53-controlled post-translational modifications on nine secreted proteins was also found. These findings will enhance our understanding of wt-p53 modulated interactions of the tumor with its environment.

[Postoperative pulmonary thromboembolism and nosocomial pneumonias: differential diagnosis]. / Pooperacní plicní tromboembolie a nozokomiální (tzv. pooperacní) pneumonie: diferenciální diagnóza.

After a surgical intervention patient can face pulmonary complication that was formerly recognised as postoperative pneumonia. This term described the clinical picture which was diagnosed after abdominal or thoracic operations, after polytraumatic lesions, especially with elderly patients that were for a longer time confined to bed rest. The clinical symptoms incl. the X ray picture were consistent with those of pneumonia - such pneumonias are nowadays classified as nosocomial infections. These complications sometimes ended fatally. The post-mortem examination revealed either pneumonia or often pulmonary thromboembolism (PTE). Occasionally it happened that PTE was incorrectly clinically diagnosed as pneumonia and the patient was treated with antibiotics instead of with heparin. The present paper brings discussion on the differential diagnosis between postoperative nosocomial pneumonia and PTE. Clinical casuistic is also added.

[Long-term monitoring of patients with clinical symptoms of upper gastrointestinal tract bleeding with a negative endoscopy result]. / Dlouhodobé sledování pacientu s klinickými známkami krvácení do horní cásti trávicího traktu a negativním endoskopickým nálezem.

The authors present the results of a long-term monitoring of patients who presented with clinical signs of bleeding from the upper gastrointestinal tract (GIT) but totally negative endoscopy results on admission. Retrospective-prospective analysis of acute endoscopies in patients with clinical signs of bleeding from the upper gastrointestinal tract performed in the Endoscopy Centre of the OstravaTeaching Hospital from 2002 to 2005, long term monitoring of the sample with negative results on admission. A total of 133 patients, i.e. 16.3 % of all acute procedures, with no source of bleeding detected in the first endoscopy. 26.4% of wrong indications. In the rest of the sample, a source of bleeding was detected by endoscopy in 17 patients (15 in an early examination and 2 within one month from the event), i.e. 17.3%. The rate of bleeding recurrence was 15%. The risk of recurrence was higher in patients with haematemesis and a decrease in the blood count (BC) at the time of the first event. In 19 patients, i.e. 14.3%, the source was not detected. In the remaining 33 patients, the findings were as follows: 1) in 4 patients, the source of bleeding was detected in the small intestine (push enteroscopy or enteroclysis); 2) in 3 patients, the source of bleeding was detected in the colon; 3) in 6 patients, IBD was detected; 4) in 5 patients, cirrhosis of the liver was diagnosed within months or years from the event.