UHPLC-Orbitrap study of the first phase tacrine in vitro metabolites and related Alzheimer's drug candidates using human liver microsomes.

Tacrine was the first drug used in the therapy of Alzheimer's disease (AD) and is one of the leading structures frequently pursued in the drug discovery of novel candidates for tackling AD. However, because tacrine has been withdrawn from the market due to its hepatotoxicity, ascribed to specific metabolites, concerns are high about the toxicity profile of newly developed compounds related to tacrine. From the point of view of drug safety, the formation of metabolites must be uncovered and analyzed. Bearing in mind that the main culprit of tacrine hepatotoxicity is its biotransformation to hydroxylated metabolites, human liver microsomes were used as a biotransformation model. Our study aims to clarify phase I metabolites of three potentially non-toxic tacrine derivatives (7-methoxytacrine, 6-chlorotacrine, 7-phenoxytacrine) and to semi-quantitatively determine the relative amount of individual metabolites as potential culprits of tacrine-based hepatotoxicity. For this purpose, a new selective UHPLC-Orbitrap method has been developed. Applying UHPLC-Orbitrap method, two as yet unpublished tacrine and 7-methoxytacrine monohydroxylated metabolites have been found and completely characterized, and the separation of ten dihydroxylated tacrine and 7-methoxytacrine metabolites was achieved for the first time. Moreover, the structures of several new metabolites of 7-phenoxytacrine and 6-chlorotacrine have been identified. In addition, the relative amount of these newly observed metabolites was determined. Based on the results and known facts about the toxicity of tacrine metabolites published so far, it appears that 7-phenoxytacrine and 6-chlorotacrine could be substantially less hepatotoxic compared to tacrine, and could potentially pave the way for metabolically safe molecules applicable in AD therapy.

[Penetrating Injuries of the Heart and Great Vessels - Fifteen Years of Experience of the Cardiac Surgery Service as a Part of the Major Trauma Centre]. / Penetrující poranení srdce a velkých cév ­ patnáctiletá zkusenost kardiochirurgického servisu v rámci primárního traumacentra.

PURPOSE OF THE STUDY Outcome analysis of penetrating cardiac and great vessels injury within the 15-year existence of the cardiac surgery service as a part of the major trauma centre of the University Hospital Olomouc MATERIAL AND METHODS Retrospective analysis of a group of a total of 16 patients who underwent a surgery for penetrating cardiac and great vessels injury since II/2002 to XI/2016. The dominant causes of penetrating trauma were stab injuries (15 patients, 94%), in one patient only (6%) it was a gunshot injury. The mean age of the patients included in the group was 42.9 ± 16.1 years, with men significantly prevailing (13 patients, 81%). A total of 7 injured persons (44%) were haemodynamically stable when admitted, 9 injured persons (56%) were unstable or in critical condition. The average transfer distance was 48.8 ± 34.5 km; the injured were admitted on average 115.9 ± 154.8 minutes after being injured. Preoperatively, all the injured suffered from pericardial effusion (>5 mm) confirmed by TTE (81%) or CTA (19%). In 4 patients (25%) pericardial drainage for cardiac tamponade was performed before surgery. RESULTS All the penetrating cardiac and great vessels injuries were repaired by cardiac surgeon, in one case only (6%) the extracorporeal circulation support was used. The injury of coronary arteries was in one case managed by CABG and in the other case by ligation of the peripheral part of the coronary artery. In 4 patients (25%) also a penetrating injury of other organs was simultaneously managed. The mean ICU stay reached 85.8 ± 91.9 hours, on average 5.6 ± 9.3 units of red blood cells were administered during the in-hospital stay which lasted on average 7.1 ± 2.4 days. In the group a nonsignificant increase of left ventricular ejection fraction (44.1 ± 4.7 vs. 49.3 ± 3.2, p = 0.882) was reported at discharge of the injured patients. One patient died on the 78 th day of hypoxic brain damage (6% three-month mortality). The long-term survival analysis showed 94% one-year and 88% five-year cumulative survival in the group. DISCUSSION The incidence of the penetrating cardiac and great vessels injury is directly dependent on the crime level in the respective countries and regions. A cardiac arrest, severe hemodynamic instability, unconsciousness, serious concomitant injury, gunshot injury, multiple or atrial injury represent independent predictors of death in these injuries. The total three-month mortality in penetrating cardiac and great vessels injury ranges from 18 to 42%, the presence of vital signs at the time of hospital admission is associated with 78-92% probability of survival. The surviving patients show excellent long-term results with the exception of those who suffered a severe damage to valve apparatus or with significantly depressed left ventricular function. CONCLUSIONS Our experience proves a high survival rate of patients with penetrating cardiac and great vessels injury. The centralisation of the care into the major trauma centre with a cardiac surgery background, a unified treatment algorithm, and a vital interdisciplinary cooperation are the key goal of successful management of these injuries. Key words:penetrating injury, cardiac injury, great vessel injury, outcome. Práce byla podporena programem institucionální podpor.

[Our experience with chest wall stabilization]. / Nase zkusenosti se stabilizací hrudníku.

INTRODUCTION: An unstable chest wall is defined as a fracture of at least three adjacent ribs broken at least in two planes. As a result of impaired mechanical strength of the chest wall, paradoxical movements occur, resulting in insufficient pulmonary ventilation with the development of respiratory insufficiency with typical consequences - hypoxia, hypercapnia and acidosis. METHODS: In this paper we describe a group of 16 patients who underwent stabilization of the chest wall. The average age of the group was 56 years, the youngest patient was 23 and the oldest one 76 years old. There was an average of 6.1 broken ribs per patient, individually ranging from 4 to 8. In 11 cases, the stabilization was performed for a block fracture, in 5 cases for a serial fracture with a thoracic wall deformity. RESULTS: The average length of hospital stay was 19 days, the time from admission to surgery was 4.46 days, and the average duration of mechanical ventilation was 2.63 days. In our group, we had only one deep wound infection that was healed using vacuum therapy. Concerning other complications, there was one case of bronchopneumonia and one patient developed delirium. No redrainage for fluido- or pneumothorax was necessary. CONCLUSION: The main focus of this paper is on the active surgical approach to treatment of serial and block fractures of ribs with deformation or manifest instability of the chest wall. Not all patients with block fracture required stabilization, whereas 5 patients with serial fracture of the ribs were indicated for surgical revision for chest wall deformity and other complications.Key words: flail chest treatment indications.

[Assessment of thoracic trauma at the 1st Department of Surgery in Brno (1 January 2011 - 31 December 2015)]. / Poranení hrudníku na I. chirurgické klinice LF MU a FN USA v Brne (vyhodnocené období 1. 1. 2011 az 31. 12. 2015).

INTRODUCTION: The number of cases of thorax injury increased steadily between 2011 and 2015. This is probably related to a more active lifestyle of the younger generations and also to the increasing average age of citizens. The aim of the study was to show problems connected with thorax injury. METHOD: Our retrospective study evaluated a group of patients with thoracic injury (diagnosis codes S20-S29) in the period from 1 January 2011 to 31 December 2015 who were treated in our Department. RESULTS: We evaluated a group of 1,697 patients with thoracic injury were divided into five subgroups: 1) simple contusion of the thorax, 2) simple rib fractures, 3) contusion of the thorax with vertebral fractures, 4) serial, multiple rib fractures, 5) stab and gunshot injuries of the thorax. Each subgroup was analyzed independently and in detail. The number of thoracic injuries increased steadily, year on year. More than 40% of the patients were older than 60 years. In the group with simple rib fractures, the authors found 14 cases of pneumothorax (5.1%), which was drained in only 8 cases. The most common complications in the serial rib fractures group included pneumothorax (33 cases, 20%), hemothorax (28 cases, 16.9%) and lung contusion (15 cases, 9%). Stabilization of the thoracic wall was performed 16 times, out of the total of 26 multiple rib fracture cases (61.5%). CONCLUSIONS: Thorax injury is routinely encountered by surgeons. The authors recommend to pay particular attention not only to serious, but also to simple thorax injuries in very old patients, for instance those on anticoagulation therapy. Adequate caution also needs to be taken with serial rib fractures and flail chest and their treatment.Key words: thorax injury - rib fractures - hemothorax - pneumothorax.

Complex gunshot injury to the heart as a consequence of suicide attempt in a schizophrenic patient.

INTRODUCTION: Self-inflicted gunshot injury to the heart is uncommon in Western Europe countries. However it is considered to have a high mortality through cardiac tamponade or exsanguination and concomitant chest or abdominal cavity injury. CASE PRESENTATION: We present a 39-year-old schizophrenic woman who attempted suicide with the aid of a 6.35mm caliber handgun, after self-discontinuing of antipsychotic treatment. Lower third of sternum, right heart atrium and ventricle and inferior caval vein were hit by the bullet which consequently got lodged in the right paravertebral muscle mass at the lower thoracic vertebral level. As she was hemodynamically unstable due to hemopericardium and a huge right hemothorax, she underwent emergent surgery. Heart and inferior vena caval injuries were repaired on extracorporeal circulation. The postoperative course was uneventful and she was transferred to a psychiatric facility on the 7th postoperative day. One year after the surgery she is well, compliant to antipsychotic medications and on periodic follow-up by psychiatrists. CONCLUSION: This case represents management of complex self-inflicted gunshot cardiac injury in a schizophrenic patient who discontinued antipsychotic medication. Liaison between themedical rescue service and high level trauma center essentially reduced injury-to-surgery time. Complex heart injury was successfully repaired on extracorporeal circulation.

[The role of surgical embolectomy and extracorporeal membrane oxygen therapy in the treatment of massive pulmonary embolism - a review]. / Role chirurgické embolektomie arteria pulmonalis a membránové mimotelní oxygenoterapie v lécbe masivní plicní embolie - prehled.

Acute massive pulmonary embolism remains potentially lethal with mortality varying between 2553%. In the thrombolytic era, surgical pulmonary embolectomy is deemed as a rescue approach for patients with absolute contraindication of thrombolysis or its failure. However, close interdisciplinary cooperation, meticulous choice of optimal reperfusion strategy, standardization of surgical approach, and mainly the inclusion of mechanical circulatory support into the treatment algorithm have led to a drop in in-hospital mortality below 10% in the last 10 years. Nevertheless, cardiac arrest and refractory cardiogenic shock still remain independent risk factors of death with mortality exceeding 70%. Extracorporeal membrane oxygen therapy provides rapid circulatory support, end-organ perfusion and oxygenation which are essential for right-sided obstruction haemodynamic. Subsequently, optimal reperfusion strategy can be chosen or patients may be transported for it. The review highlights the contemporary role of surgical pulmonary embolectomy and extracorporeal membrane oxygen therapy in the treatment algorithm for acute massive pulmonary embolism, summarising current perspectives on the indications and contraindications for these treatment strategies and their results.Key words: massive pulmonary embolism - surgical pulmonary embolectomy - extracorporeal membrane oxygen therapy.

[Stabilisation of the dislocated acromioclavicular joint and lateral fractures of the clavicle using a hook plate]. / Stabilizace luxace AC skloubení a zlomenin akromiálního konce klícku pomocí háckové dlahy.

INTRODUCTION: The aim of this study was to verify the hypothesis that the technique of stabilizing the acromioclavicular joint and lateral fractures of the clavicle using a clavicular hook plate can be considered a method of choice in the given types of injury. MATERIAL AND METHODS: The clinical part of the study included a total of 40 patients. The indication group was formed by patients with type III acromioclavicular joint dislocation, according to Tossy. As for lateral fractures of the clavicle, the patients of group II and types IIa, IIb according to revised Allman and Neers classification, underwent surgery. 40 patients with type III acromioclavicular luxation, operated on at the same clinic, were chosen as the control group; however, the technique of traction cerclage was used here. RESULTS: When evaluating our results, we recorded a lower occurrence of infectious complications in patients with a hook plate. No method failure or joint redislocation was observed in the hook plate group. There was no change in position even after the implant was removed. On the other hand, where traction cerclage was used, redislocation in the acromioclavicular joint occurred due to mechanical failure in 5 cases, in 15 cases mechanical implant failure was seen. As for patients with a hook plate, 11 cases showed irritation of the lower surface of the acromion. Statistical evaluation of parameters of the main set of patients was carried out in cooperation with the Institute of Biostatistics and Analyses of Masaryk University in Brno. CONCLUSION: Based on our results, the stabilisation of complete acromioclavicular separation and lateral end clavicle fractures using clavicle hook plate can be regarded as a suitable method for treating these lesions. Timely removal of the implant within 12 weeks of the intervention is needed to prevent irritation of the lower surface of the acromion.

Radical D2 surgery for patients with gastric cancer.

UNLABELLED: The authors analyzed and prepared a report concerning 18 radical surgeries for gastric cancer that were performed between 1999-2001. Overall, 55 operation were performed, 32 radical, 18 palliative and 5 explorative laparatomies. D2 resections were performed 18 times, while D1 type 14 times. The group undergoing D2 surgery comprised of 10 men and 8 women with average age of 64.3. D2 resection included partial (8 times), or total (10) gastrectomy and lymfadenectomy of perigastric nodes, supra and infrapyloric nodes and nodes along common hepatic artery, truncus coeliacus, lienal artery, left paracardial nodes and removing capsula of pancreas. Splenectomy was performed twice. On average, 37.5 lymphnodes were removed for every operation (25-69). Operative mortality was none (0%) and morbidity was 22%. As of January 1, 2002 relaps was noted in six patients, and 5 patients died. CONCLUSION: D2 resection surgeries performed by an experienced surgeon show low morbidity as well as better outcome and higher perspective for long-term survival in patients with gastric cancer. (Tab. 1, Ref. 19.).

Perforation peritonitis in primary intestinal tuberculosis.

Primary intestinal tuberculosis is unusual in European and North American countries today. Its diagnosis is often surprising and differentiation from inflammatory bowel diseases is difficult. The authors present a rare case of severe stercoral peritonitis caused by multiple intestinal perforations in a patient with primary ileocecal tuberculosis. Initial clinical and laboratory investigations led to the suspicion of inflammatory bowel disease. The subsequent diagnostic workup included colonoscopic examination of the cecal and terminal region of the ileum with multiple biopsies. After the pathologist had assessed the specimen as indicating Crohn's disease, appropriate therapy was initiated. Several days later, however, the patient was readmitted to a surgical intensive care unit with clinical signs of peritonitis and immediately operated on. The final diagnosis from a resection specimen confirmed the diagnosis of primary intestinal tuberculosis. The follow-up was complicated by a subhepatic abscess formation with the necessity for surgical drainage. The patient's recovery was uneventful, she underwent intensive antituberculotic therapy and is asymptomatic at present. Surgeons caring for patients with acute abdomen should be aware of tuberculous perforation peritonitis even in non-risk groups of patients.

Concurrent neutral evolution of mRNA secondary structures and encoded proteins.

Messenger RNA sequences often have to preserve functional secondary structure elements in addition to coding for proteins. We present a statistical analysis of retroviral mRNA which supports the hypothesis that the natural genetic code is adapted to such complementary coding. These sequences are still able to explore efficiently the space of possible proteins by point mutations. This is borne out by the observation that, in stem regions of retroviral mRNA foldings, silent mutations on one strand are preferentially accompanied by conservative mutations on the other. Distances between amino acids based on physicochemical properties are used to quantify the conservation of protein function under the constraint of maintained RNA secondary structure. We find that preservation of RNA secondary structure by compensatory mutations is evolutionary compatible with the efficient search for new variants on the protein level.

[Radical treatment of rectal cancer]. / Radikálna liecba rakoviny konecníka.

The authors present an account on radical resections of the rectum in 73 patients during 1991-1995. A radical operation with excision of the mesorectum was performed 69 times, local excisions 4 times. Five-year survival was recorded in 57.90% patients, local relapses were recorded in 10.14% patients. Remote metastases or generalization of the disease was found in 18.84% patients. Adjuvant treatment was administered to 74% patients.

Model calculation of radiocaesium transfer into food products in semi-natural forest ecosystems in the Czech Republic after a nuclear reactor accident and an estimate of the population dose burden.

Radioactivity of food products from semi-natural forest ecosystems can contribute appreciably to the radiological burden of the human population following a nuclear accident, as found after the Chernobyl disaster in 1986. In the Czech Republic, radiocaesium radioactivity has been measured since 1986 in various components of forest ecosystems, such as soil, mushrooms, bilberries, deer and boar. In this work, the data are employed to predict how a model accident of the Temelín nuclear power plant in southern Bohemia (which is under construction) would affect selected forest ecosystems in its surroundings. The dose commitment to the critical population group is also estimated.

Complementary coding conforms to the primeval comma-less code.

The hypothesis that the universal genetic code is adapted to double-strand coding is supported by its remarkable compatibility with the RNY comma-less hypothesis. Coding by a triplet code on a polynucleotide double-strand allows for enciphering of five additional messages with reference to a chosen primary reading frame. Assuming the acceptance of coupled mutations on both strands, the best codon register for two overlapping messages can be inferred. The idea of evolutionarily compatible coding of two proteins by one nucleotide double-strand is extended to complementary coding for one protein in folded, single-stranded RNA.

Neutral adaptation of the genetic code to double-strand coding.

We lay new foundations to the hypothesis that the genetic code is adapted to evolutionary retention of information in the antisense strands of natural DNA/RNA sequences. In particular, we show that the genetic code exhibits, beyond the neutral replacement patterns of amino acid substitutions, optimal properties by favoring simultaneous evolution of proteins encoded in DNA/RNA sense-antisense strands. This is borne out in the sense-antisense transformations of the codons of every amino acid which target amino acids physicochemically similar to each other. Moreover, silent mutations in the sense strand generate conservative ones in its antisense counterpart and vice versa. Coevolution of proteins coded by complementary strands is shown to be a definite possibility, a result which does not depend on any physical interaction between the coevolving proteins. Likewise, the degree to which the present genetic code is dedicated to evolutionary sense-antisense tolerance is demonstrated by comparison with many randomized codes. Double-strand coding is quantified from an information-theoretical point of view.

In vitro dissolution profile of water-insoluble drug dosage forms in the presence of surfactants.

The determination of the in vitro release profile of water-insoluble drug products requires dissolution media different from those used for water-soluble drug products. Since the relevance of drug dissolution in organic solvents is questionable, we investigated the use of surfactants to determine the dissolution profiles of water-insoluble drug products. In most cases, the drug dissolution rate and extent increased as the surfactant concentration in the aqueous dissolution medium increased. Suitable dissolution profiles were obtained in the presence of sodium lauryl sulfate (SLS) for water-insoluble drug products, such as griseofulvin, carbamazepine, clofibrate, medroxyprogesterone, and cortisone acetate. These findings recommend the use of surfactants for determining the aqueous dissolution of water-insoluble drug products rather than adding organic solvents to the dissolution medium.