Hydrogen sulfide (H2S) is a gas neurotransmitter that is synthesized in various mammalian tissues including vascular tissues and regulates vascular tone. The aim of this study is to investigate whether the endogenous L-cysteine/H2S pathway is impaired due to aging and endothelial denudation in mouse isolated thoracic aorta. For this purpose, young (3-4 months) and old (23-25 months) mice were used in the experiments. The effects of aging and endothelium on endogenous and exogenous H2S-induced vasorelaxation were investigated by cumulative L-cysteine-(1 microM-10 mM) and NaHS-(1 microM-3 mM) induced vasorelaxations, respectively. The L-cysteine-induced relaxations were reduced in old mice aorta compared to the young mice. Also, vasorelaxant responses to L-cysteine (1 microM-10 mM) were reduced on aorta rings with denuded-endothelium of young and old mice. However, the relaxation responses to NaHS were not altered by age or endothelium denudation. The loss of staining of CSE in the endothelial layer was observed in old thoracic aorta. Ach-induced (1-30 microM) relaxation almost abolished in endothelium-denuded rings from both mice group. Also, relaxation Ach reduced in intact endothelium tissue of old mice aorta. In conclusion, the vasorelaxant responses to L-cysteine but not NaHS decreased and the protein expression of CSE reduced in old thoracic aorta rings consistent with a decrease in H2S concentration with aging and endothelium damage, suggesting that aging may be lead to decrease in enzyme expression and H2S signaling system due to endothelium damage in mouse thoracic aorta. Key words Aging, Hydrogen sulfide, L-cysteine, Endothelium, Thoracic aorta.

• MeSH
• aorta thoracica * metabolismus   účinky léků   MeSH
• cévní endotel * metabolismus   účinky léků   MeSH
• cystathionin-gama-lyasa metabolismus   MeSH
• cystein farmakologie   metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• signální transdukce fyziologie   MeSH
• stárnutí * metabolismus   fyziologie   MeSH
• sulfan * metabolismus   farmakologie   MeSH
• vazodilatace * účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cystathionin-gama-lyasa MeSH
• cystein MeSH
• sulfan * MeSH

Aortic dissection is a life-threatening disease that consists in the development of a tear in the wall of the aorta. The initial tear propagates as a discontinuity leading to separation within the aortic wall, which can result in the creation of a so-called false lumen. A fatal threat occurs if the rupture extends through the whole thickness of the aortic wall, as blood may then leak. It is generally accepted that the dissection, which can sometime extend along the entire length of the aorta, propagates via a delamination mechanism. The aim of the present paper is to provide experimentally validated parameters of a mathematical model for the description of the wall's cohesion. A model of the peeling experiment was built in Abaqus. The delamination interface was described by a piecewise linear traction-separation law. The bulk behavior of the aorta was assumed to be nonlinearly elastic, anisotropic, and incompressible. Our simulations resulted in estimates of the material parameters for the traction-separation law of the human descending thoracic aorta, which were obtained by minimizing the differences between the FEM predictions and the delamination force given by the regression of the peeling experiments. The results show that the stress at damage initiation, Tc, should be understood as an age-dependent quantity, and under the assumptions of our model this dependence can be expressed by linear regression as Tc = - 13.03·10-4·Age + 0.2485 if the crack front advances in the axial direction, and Tc = - 7.58·10-4·Age + 0.1897 if the crack front advances in the direction of the aortic circumference (Tc [MPa], Age [years]). Other model parameters were the stiffness K and the separation at failure, δf-δc (K = 0.5 MPa/mm, δf-δc = 0.1 mm). The material parameters provided by our study can be used in numerical simulations of the biomechanics of dissection propagation through the aorta especially when age-associated phenomena are studied.

• Klíčová slova
• Aging, Cohesive model, Crack, Damage, Finite elements method, Fracture,
• MeSH
• analýza metodou konečných prvků MeSH
• aorta thoracica * fyziologie   MeSH
• biomechanika MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mechanický stres MeSH
• modely kardiovaskulární MeSH
• počítačová simulace MeSH
• senioři MeSH
• stárnutí fyziologie   MeSH
• trakce MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: The activity of perivascular adipose tissue (PVAT), a specific deposit of adipose tissue surrounding blood vessels, could contribute to sex differences in vascular tone control, particularly in dyslipidemic disorders; however, the mutual associations remain unclear. This study aimed to evaluate the relationships among sex, PVAT and vascular function in Wistar and hereditary hypertriglyceridemic (HTG) rats. Vasoactive responses of the isolated thoracic aorta with preserved or removed PVAT were compared in adult male and female Wistar and HTG rats, and the roles of nitric oxide (NO), hydrogen sulfide (H2S), cyclooxygenase (COX) and inflammatory signaling in vascular function were monitored in females. RESULTS: HTG rats were hypertensive, but females less than males. Increased 2-h glycemia was observed in HTG rats regardless of sex; however, HTG females exhibited better glucose utilization than males did. Females, independent of strain, had better preserved endothelial function than males did. PVAT inhibited endothelium-dependent relaxation in all the rats except HTG females. In HTG males, pathologically increased aortic contractility was noted; however, in HTG females, the contractile responses were lower, thus approaching physiological levels despite the pro-contractile action of COX products. In HTG females, NO contributed to endothelial function to a lesser extent than it did in controls, but the presence of PVAT eliminated this difference, which corresponded with increased NO synthase activity. Although increased protein expression of several proinflammatory factors (TNFα, IL-6, iNOS, and NfκB) was confirmed in the aortic and PVAT tissue of HTG females, the protein expression of factors regulating the adhesion and infiltration of monocytes (ICAM-1 and MCP-1) was decreased in PVAT. Moreover, in HTG females, unlike in controls, H2S produced by PVAT did not inhibit endothelial relaxation, and regardless of PVAT, endogenous H2S had beneficial anticontractile effects, which were associated with increased protein expression of H2S-producing enzymes in both aortic and PVAT tissues. CONCLUSIONS: Despite increased inflammation and the pathological impact of cyclooxygenase signaling in female HTG rats, protective vasoactive mechanisms associated with milder hypertension and improved endothelial function and contractility linked to PVAT activity were triggered. Sulfide and nitroso signaling represent important compensatory vasoactive mechanisms against hypertriglyceridemia-associated metabolic disorders and may be promising therapeutic targets in prediabetic females.

• Klíčová slova
• Hereditary hypertriglyceridaemic rats, Hydrogen sulfide, Nitric oxide, Perivascular adipose tissue, Sex,
• MeSH
• aorta thoracica patofyziologie   MeSH
• cévní endotel patofyziologie   MeSH
• krysa rodu Rattus MeSH
• oxid dusnatý * metabolismus   MeSH
• potkani Wistar * MeSH
• prediabetes * patofyziologie   metabolismus   MeSH
• sexuální faktory MeSH
• signální transdukce * fyziologie   MeSH
• sulfan * metabolismus   MeSH
• tuková tkáň metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• oxid dusnatý * MeSH
• sulfan * MeSH

Substituted catechols include both natural and synthetic compounds found in the environment and foods. Some of them are flavonoid metabolites formed by the gut microbiota which are absorbed afterwards. Our previous findings showed that one of these metabolites, 4-methylcatechol, exerts potent vasorelaxant effects in rats. In the current study, we aimed at testing of its 22 structural congeners in order to find the most potent structure and to investigate the mechanism of action. 3-methoxycatechol (3-MOC), 4-ethylcatechol, 3,5-dichlorocatechol, 4-tert-butylcatechol, 4,5-dichlorocatechol, 3-fluorocatechol, 3-isopropylcatechol, 3-methylcatechol and the parent 4-methylcatechol exhibited high vasodilatory activities on isolated rat aortic rings with EC50s ranging from ∼10 to 24 μM. Some significant sex-differences were found. The most potent compound, 3-MOC, relaxed also resistant mesenteric artery but not porcine coronary artery, and decreased arterial blood pressure in both male and female spontaneously hypertensive rats in vivo without affecting heart rate. It potentiated the vasodilation mediated by cAMP and cGMP, but did not impact L-type Ca2+-channels. By using two inhibitors, activation of voltage-gated potassium channels (KV) was found to be involved in the mechanism of action. This was corroborated by docking analysis of 3-MOC with the KV7.4 channel. None of the most active catechols decreased the viability of the A-10 rat embryonic thoracic aorta smooth muscle cell line. Our findings showed that various catechols can relax vascular smooth muscles and hence could provide templates for developing new antihypertensive vasodilator agents without affecting coronary circulation.

• Klíčová slova
• Blood vessel, Catechol, K(V) channel, Phenolic, Vasorelaxant,
• MeSH
• aorta thoracica účinky léků   metabolismus   MeSH
• arteriae mesentericae * účinky léků   metabolismus   MeSH
• arteriální tlak účinky léků   MeSH
• draslíkové kanály řízené napětím metabolismus   antagonisté a inhibitory   účinky léků   MeSH
• guanosinmonofosfát cyklický metabolismus   MeSH
• hypertenze farmakoterapie   patofyziologie   metabolismus   MeSH
• katecholy * farmakologie   chemie   MeSH
• koronární cévy účinky léků   metabolismus   MeSH
• krysa rodu Rattus MeSH
• modely nemocí na zvířatech MeSH
• myocyty hladké svaloviny účinky léků   metabolismus   MeSH
• potkani inbrední SHR * MeSH
• prasata MeSH
• sexuální faktory MeSH
• simulace molekulového dockingu * MeSH
• svaly hladké cévní účinky léků   metabolismus   MeSH
• vazodilatace * účinky léků   MeSH
• vazodilatancia * farmakologie   chemie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• draslíkové kanály řízené napětím MeSH
• guanosinmonofosfát cyklický MeSH
• katecholy * MeSH
• vazodilatancia * MeSH

Power hammers are mechanised forging devices that constitute a pivotal part of steel manufacturing. Power hammer-associated injuries are a rare occurrence. We report a noteworthy case of a 52-year-old man who sustained a high-energy penetrating injury while working with a power (counterblow) hammer. The man used a sizable disc-shaped metallic object to dislodge the forging wedged in the machine by applying the force of the striking ram on it. On impact, the object ejected and struck the man in the right lateral portion of the chest. The autopsy disclosed extensive damage to the thoracic and abdominal organs. The cause of death was opined to be exsanguination due to penetrating trauma of the heart and transection of the descending aorta. The investigation confirmed a breach of safety regulations. To the best of our knowledge, this is the first power (counterblow) hammer-related fatality in medico-legal literature.

• Klíčová slova
• autopsy, discharged flying object, forensic pathology, high‐mass penetrating injury, power hammer, safety protocol, work‐related fatality,
• MeSH
• aorta thoracica zranění   patologie   MeSH
• cizí tělesa patologie   MeSH
• exsanguinace * etiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• penetrující rány * patologie   MeSH
• poranění srdce patologie   MeSH
• pracovní nehody MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

INTRODUCTION: Thoracic aorta false aneurysms (TAFA) are unexplored complications after cardiac surgery associated with significant morbidity and mortality. Therefore, the purpose of this study was to examine the clinical profiles, surgical techniques, and operative outcomes, of patients treated for TAFA at a single institution. METHODS: From 1996 to 2022, 112 patients were treated for aortic pseudoaneurysm (mean age 55 ± 14 years, 78 patients were male). In the majority of the patients (90%) TAFA developed after previous cardiovascular surgery, the most common diagnosis and surgical procedure preceding the TAFA development was an aortic dissection (52%) and Bentall procedure (47%). In the rest of the cohort, the leading cause was trauma. RESULTS: Sixty-one percent of patients were indicated for reintervention (surgical reoperation, endoluminal graft implantation, septal occluder implantation, coil embolization, or a combination of procedures). Overall, 52 patients had undergone cardiac reoperation. TAFA was resected and the aorta was repaired in 55% or replaced in 45%. Operative mortality was 5.7%. In postoperative follow-up, a hypoechogenic lesion encircling aortic prosthesis was present in 94%, therefore it was determined as a negative prognostic factor. The mean follow-up was 13.2 ± 19.4 years. CONCLUSION: Although there is no specific approach how to prevent TAFA development, maintaining normal blood pressure and regular follow-up should be applied. More frequent follow-ups should be performed in patients with a hypoechogenic lesion encircling and aortic prosthesis. Early detection during long-term postoperative follow-up, an individually tailored approach of a multidisciplinary team is necessary for favorable treatment outcomes.

• Klíčová slova
• Aortic dissection, Aortic pseudoaneurysm, Bentall surgery, Endoluminal graft implantation, Septal occluder implantation,
• MeSH
• aneurysma hrudní aorty * chirurgie   MeSH
• aorta thoracica chirurgie   diagnostické zobrazování   MeSH
• časové faktory MeSH
• cévy - implantace protéz škodlivé účinky   MeSH
• dospělí MeSH
• endovaskulární výkony škodlivé účinky   MeSH
• kombinovaná terapie MeSH
• lidé středního věku MeSH
• lidé MeSH
• nepravé aneurysma * chirurgie   etiologie   diagnostické zobrazování   terapie   MeSH
• pooperační komplikace etiologie   chirurgie   MeSH
• reoperace MeSH
• retrospektivní studie MeSH
• rizikové faktory MeSH
• senioři MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Extended aortic repair is considered a key issue for the long-term durability of surgery for DeBakey type 1 aortic dissection. The risk of aortic degeneration may be higher in young patients due to their long life expectancy. The early outcome and durability of aortic surgery in these patients were investigated in the present study. METHODS: The subjects of the present analysis were patients under 60 years old who underwent surgical repair for acute DeBakey type 1 aortic dissection at 18 cardiac surgery centres across Europe between 2005 and 2021. Patients underwent ascending aortic repair or total aortic arch repair using the conventional technique or the frozen elephant trunk technique. The primary outcome was 5-year cumulative incidence of reoperation on the distal aorta. RESULTS: Overall, 915 patients underwent surgical ascending aortic repair and 284 patients underwent surgical total aortic arch repair. The frozen elephant trunk procedure was performed in 128 patients. Among 245 propensity score-matched pairs, total aortic arch repair did not decrease the rate of distal aortic reoperation compared to ascending aortic repair (5-year cumulative incidence, 6.7% versus 6.7%, subdistributional hazard ratio 1.127, 95% c.i. 0.523 to 2.427). Total aortic arch repair increased the incidence of postoperative stroke/global brain ischaemia (25.7% versus 18.4%, P = 0.050) and dialysis (19.6% versus 12.7%, P = 0.003). Five-year mortality was comparable after ascending aortic repair and total aortic arch repair (22.8% versus 27.3%, P = 0.172). CONCLUSIONS: In patients under 60 years old with DeBakey type 1 aortic dissection, total aortic arch replacement compared with ascending aortic repair did not reduce the incidence of distal aortic operations at 5 years. When feasible, ascending aortic repair for DeBakey type 1 aortic dissection is associated with satisfactory early and mid-term outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04831073.

• MeSH
• aneurysma hrudní aorty chirurgie   mortalita   MeSH
• aorta thoracica * chirurgie   MeSH
• cévy - implantace protéz * metody   škodlivé účinky   mortalita   MeSH
• disekce aorty * chirurgie   mortalita   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• pooperační komplikace * epidemiologie   MeSH
• reoperace * statistika a číselné údaje   MeSH
• retrospektivní studie MeSH
• tendenční skóre MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH

INTRODUCTION: False aneurysms in the thoracic aorta are dangerous complications that can occur after cardiac surgery. They often result in high mortality rates. These aneurysms are caused by damage to all layers of the aortic wall. This study aimed to pinpoint the area of the experimental specimen (native vessel, anastomosis, or prosthetic graft) with the greatest deformation, to determine whether a false aneurysm is likely to develop in the anastomotic portion. METHODS: We conducted the inflation-extension test by performing eight cycles ranging from 0 to 20. The pressure sampling frequency was 100 Hz, and each cycle lasted approximately 34 seconds, resulting in a loading frequency of 0.03 Hz. During the experiment, each camera captured 3,000 frames. Based on the data collected, we evaluated and compared the loading stages of cycle 1 and cycle 8. RESULTS AND DISCUSSION: During loading, the native vessel experienced a dominant deformation of approximately 7% in the circumferential direction. The prosthetic graft, which had a longitudinal construction, deformed by approximately 8% in the axial direction. The prosthetic graft, on the other hand, only experienced a deformation of up to 1.5% in the circumferential direction, which was about 5 times smaller than the deformation of the native vessel. The anastomosis area was very stiff and showed minimal deformation. Additionally, there was little difference in the mechanical response between the first C1 and the eighth C8 cycle. CONCLUSION: Based on the available evidence, it can be inferred that aortic false aneurysms are more likely to form just behind the suture lines in the native aorta, which is more elastic compared to stiff sections of anastomosis and prosthetic graft. Numerous pulsations of the native vessel will likely cause the impairment of the aorta at the margin of the anastomosis. This will lead to disruption of the aortic wall and false aneurysm formation in the native vessel near the area of anastomosis.

• Klíčová slova
• Aortic pseudoaneurysm, The inflation-extension test, Thoracic aortic false aneurysm,
• MeSH
• anastomóza chirurgická škodlivé účinky   MeSH
• aorta thoracica chirurgie   MeSH
• aortální aneurysma * komplikace   MeSH
• lidé MeSH
• nepravé aneurysma * diagnóza   etiologie   chirurgie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

INTRODUCTION: Biomechanical rupture risk assessment of aortic tissues is commonly based on computed stress to measured uniaxial static strength comparison. Loading of the arterial wall, however, is cyclic; thus, the static strength may not be a proper limit value. This study investigates the low cycle fatigue of porcine aortic samples tested in a circumferential direction. METHODS: 7 porcine descending aorta (both thoracic and abdominal) were harvested and 56 dogbone-shaped samples were prepared. Static strength was measured, the limit of engineering stress was chosen and then force controlled cyclic loading was performed up to 100,000 cycles. Efforts were made to obtain a sufficient number of points across the entire range of 0-100,000 cycles. Data were fitted by both linear and logarithmic law and extrapolated towards 1 cycle for validation against static strength/ultimate tension. Data dispersion was evaluated via normalised root mean square error. RESULTS: Out of 56 samples from 7pigs, 28 samples from 4 pigs were successfully tested. There was a strong negative correlation between applied stress/tension and number of cycles to failure. The fitting of both linear and logarithmic values resulted in a similar accuracy (R2=0.72 and 0.71 for stress and R2=0.62 and 0.7 for tension, respectively), while predicting static failure properties was more accurate by logarithmic law. NRMSE was lower for absolute values (20-21%) than for relative values (27-30%). CONCLUSIONS: Absolute values of cyclic strength and tension are less dispersed than relative ones. Logarithmic fits are more robust in predicting static strength from cyclic data, while linear fits serve as a lower limit estimation.

• Klíčová slova
• Abdominal aorta, Low cycle fatigue, Mechanical testing,
• MeSH
• aorta thoracica * MeSH
• aorta * MeSH
• biomechanika MeSH
• mechanický stres MeSH
• pevnost v tahu MeSH
• pilotní projekty MeSH
• prasata MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Soft tissue sample thickness measurement is one of the major sources of differences between mechanical responses published by different groups. New method for the estimation of unloaded sample thickness of soft tissues is proposed in this study. Ten 30 × 30 mm and ten 20 × 20 mm samples of porcine anterior thoracic aortas were loaded by gradually increased radial force. Their deformed thickness was then recorded in order to generate a pressure-thickness response. Next, the limit pressure to which the response can be considered linear was estimated. Line was fitted to the linear part of the curve and extrapolated towards zero pressure to estimate unloaded thickness (7 kPa fit). For comparison, data near zero pressure were fitted separately and extrapolated towards zero (Near Zero fit). The limit pressure for the linearity of the response was around 7 kPa. The Unloaded thickness for 30 × 30 mm samples was 2.68 ± 0.31 mm and 2.68 ± 0.3 mm for Near Zero fit and 7 kPa fit, respectively. The Unloaded thickness for 20 × 20 mm samples was 2.60 ± 0.35 mm and 2.59 ± 0.35 mm for Near Zero fit and 7 kPa fit, respectively. The median of thickness difference between smaller and larger samples was not found statistically different. Proposed method can estimate unloaded undeformed sample thickness quickly and reliably.

• MeSH
• aorta thoracica * MeSH
• mechanický stres MeSH
• prasata MeSH
• tlak MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH