The aim of this study was to test the hypothesis that individuals with an increase in HbA1c (i.e. above the regular but below the diabetic threshold) exhibit an impairment in the Achilles tendon structure and walking capacity, due to the adverse effect of the advanced glycation end-product. One hundred fifty-eight participants matched for gender, age, physical activity and BMI, were divided in two cohorts based on the HbA1c level: normal HbA1c (NGH; <39 mmol/molHb; n = 79) and altered HbA1c (AGH; >=39 mmol/molHb; n = 79). Each participant performed several walking trials to evaluate the kinematic parameters during walling at the self-selected speed and a quantitative MRI scan of the Achilles tendon (AT) to obtain its intrinsic characteristics (i.e. T2* relaxation time short and long component). The AT T2* relaxation time short component (a parameter related to the tendon collagen quality) was reduced in AGH compared to NGH. Furthermore, AGH exhibited a slower self-selected walking speed (NGH: 1.59 ± 0.18 m/s; AGH:1.54 ± 0.16 m/s) and a shorter stride length (NGH: 1.59 ± 0.13 m; AGH:1.55 ± 0.11 m). Our data suggest that a non-pathological increase in HbA1c is able to negatively affect AT collagen quality and walking capacity in healthy people. These results highlight the importance of glycemic control, even below the pathological threshold. Since diabetes could alter several biological pathways, further studies are necessary to determine which mechanisms and their timing, regarding the HbA1c rise, affect tendon composition and, consequently, walking capacity.
- MeSH
- Achilles Tendon * diagnostic imaging physiology metabolism MeSH
- Biomechanical Phenomena MeSH
- Walking * physiology MeSH
- Diabetes Mellitus diagnosis MeSH
- Adult MeSH
- Glycated Hemoglobin * metabolism MeSH
- Middle Aged MeSH
- Humans MeSH
- Magnetic Resonance Imaging MeSH
- Glycation End Products, Advanced metabolism MeSH
- Healthy Volunteers MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: This study aimed to assess the mid-term effects of focused extracorporeal shockwave therapy (ESWT) on clinical symptoms and tendon structure in patellar tendinopathy. Ultrasound (US) evaluation and an innovative in vivo analysis of intra-tendinous morphology using validated spatial frequency analysis (SFA) software were employed to quantify the organization and density of collagen fascicles. METHODS: This prospective cohort study included 21 recreational athletes (mean age 29.9 ± 9.3 years) with chronic unilateral symptomatic patellar tendinopathy. ESWT was applied as monotherapy over four weekly sessions. Pain was assessed using the Numeric Rating Scale (NRS) and disease severity with the Victorian Institute of Sports Assessment - Patella (VISA-P) questionnaire. Morphological parameters, such as tendon diameter (TD), were assessed with US and analyzed using SFA software. The asymptomatic tendons served as controls. Follow-up assessments were conducted at the end of the treatment period and 3 months posttreatment. RESULTS: Baseline evaluations revealed increased TD in proximal part of the tendon ( P = 0.001) and decreased organization of collagen fascicles ( P = 0.013) in symptomatic tendons compared to asymptomatic controls. At the 3-month follow-up, symptomatic tendons showed significant reductions in TD ( P < 0.001) and improvements in both organization and density of collagen fascicles throughout various parameters - peak spatial frequency radius (PSFR) ( P = 0.024), P6 ( P = 0.05), Q6 ( P = 0.016), PPP ( P = 0.003). No significant morphological changes were observed in asymptomatic tendons. Clinical evaluations demonstrated significant reductions in NRS ( P < 0.001) and increases in Victorian Institute of Sports Assessment - Patella (VISA-P) scores ( P < 0.001) at all time points. CONCLUSION: The study suggests that ESWT may have the potential to induce positive structural changes in patellar tendinopathy, including improved organization and density of collagen fascicles. These findings indicate that ESWT could be a promising noninvasive approach to managing patellar tendinopathy, with observed improvements in clinical symptoms and tendon structure. However, further high-quality research is needed to confirm these results and establish their long-term efficacy.
- MeSH
- Adult MeSH
- Extracorporeal Shockwave Therapy * methods MeSH
- Humans MeSH
- Patellar Ligament * diagnostic imaging pathology MeSH
- Young Adult MeSH
- Prospective Studies MeSH
- Tendinopathy * therapy diagnostic imaging pathology MeSH
- Ultrasonography MeSH
- Treatment Outcome MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Since cell dying in heart failure (HF) may vary based on the aetiology, we examined the main forms of regulated necrosis, such as necroptosis and pyroptosis, in the hearts damaged due to myocardial infarction (MI) or pressure overload. We also investigated the effects of a drug inhibiting RIP3, a proposed convergent point for both these necrosis-like cell death modes. In rat hearts, left ventricular function, remodelling, pro-cell death, and pro-inflammatory events were investigated, and the pharmacodynamic action of RIP3 inhibitor (GSK'872) was assessed. Regardless of the HF aetiology, the heart cells were dying due to necroptosis, albeit the upstream signals may be different. Pyroptosis was observed only in post-MI HF. The dysregulated miRNAs in post-MI hearts were accompanied by higher levels of a predicted target, HMGB1, its receptors (TLRs), as well as the exacerbation of inflammation likely originating from macrophages. The RIP3 inhibitor suppressed necroptosis, unlike pyroptosis, normalised the dysregulated miRNAs and tended to decrease collagen content and affect macrophage infiltration without affecting cardiac function or structure. The drug also mitigated the local heart inflammation and normalised the higher circulating HMGB1 in rats with post-MI HF. Elevated serum levels of HMGB1 were also detected in HF patients and positively correlated with C-reactive protein, highlighting pro-inflammatory axis. In conclusion, in MI-, but not pressure overload-induced HF, both necroptosis and pyroptosis operate and might underlie HF pathogenesis. The RIP3-targeting pharmacological intervention might protect the heart by preventing pro-death and pro-inflammatory mechanisms, however, additional strategies targeting multiple pro-death pathways may exhibit greater cardioprotection.
- MeSH
- Ventricular Function, Left drug effects MeSH
- Protein Kinase Inhibitors * pharmacology MeSH
- Myocytes, Cardiac * drug effects pathology enzymology MeSH
- Rats MeSH
- MicroRNAs metabolism genetics MeSH
- Disease Models, Animal MeSH
- Necroptosis * drug effects MeSH
- Necrosis MeSH
- Rats, Sprague-Dawley MeSH
- Pyroptosis * drug effects MeSH
- Ventricular Remodeling drug effects MeSH
- Receptor-Interacting Protein Serine-Threonine Kinases * antagonists & inhibitors metabolism MeSH
- Heart Failure * pathology enzymology physiopathology drug therapy etiology genetics MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Chronic lymphocytic leukemia (CLL) is a common adult leukemia characterized by the accumulation of neoplastic mature B cells in blood, bone marrow, lymph nodes, and spleen. The disease biology remains unresolved in many aspects, including the processes underlying the disease progression and relapses. However, studying CLL in vitro poses a considerable challenge due to its complexity and dependency on the microenvironment. Several approaches are utilized to overcome this issue, such as co-culture of CLL cells with other cell types, supplementing culture media with growth factors, or setting up a three-dimensional (3D) culture. Previous studies have shown that 3D cultures, compared to conventional ones, can lead to enhanced cell survival and altered gene expression. 3D cultures can also give valuable information while testing treatment response in vitro since they mimic the cell spatial organization more accurately than conventional culture. METHODS: In our study, we investigated the behavior of CLL cells in two types of material: (i) solid porous collagen scaffolds and (ii) gel composed of carboxymethyl cellulose and polyethylene glycol (CMC-PEG). We studied CLL cells' distribution, morphology, and viability in these materials by a transmitted-light and confocal microscopy. We also measured the metabolic activity of cultured cells. Additionally, the expression levels of MYC, VCAM1, MCL1, CXCR4, and CCL4 genes in CLL cells were studied by qPCR to observe whether our novel culture approaches lead to increased adhesion, lower apoptotic rates, or activation of cell signaling in relation to the enhanced contact with co-cultured cells. RESULTS: Both materials were biocompatible, translucent, and permeable, as assessed by metabolic assays, cell staining, and microscopy. While collagen scaffolds featured easy manipulation, washability, transferability, and biodegradability, CMC-PEG was advantageous for its easy preparation process and low variability in the number of accommodated cells. Both materials promoted cell-to-cell and cell-to-matrix interactions due to the scaffold structure and generation of cell aggregates. The metabolic activity of CLL cells cultured in CMC-PEG gel was similar to or higher than in conventional culture. Compared to the conventional culture, there was (i) a lower expression of VCAM1 in both materials, (ii) a higher expression of CCL4 in collagen scaffolds, and (iii) a lower expression of CXCR4 and MCL1 (transcript variant 2) in collagen scaffolds, while it was higher in a CMC-PEG gel. Hence, culture in the material can suppress the expression of a pro-apoptotic gene (MCL1 in collagen scaffolds) or replicate certain gene expression patterns attributed to CLL cells in lymphoid organs (low CXCR4, high CCL4 in collagen scaffolds) or blood (high CXCR4 in CMC-PEG).
- MeSH
- Cell Culture Techniques methods MeSH
- Leukemia, Lymphocytic, Chronic, B-Cell * pathology metabolism MeSH
- Gels chemistry MeSH
- Collagen * chemistry pharmacology MeSH
- Humans MeSH
- Polyethylene Glycols * chemistry MeSH
- Receptors, CXCR4 metabolism MeSH
- Carboxymethylcellulose Sodium * chemistry pharmacology MeSH
- Cell Culture Techniques, Three Dimensional methods MeSH
- Tissue Scaffolds * chemistry MeSH
- Cell Survival drug effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Successful engraftment of skin grafts highly depends on the quality of the wound bed. Good quality of blood vessels near the surface is critical to support the viability of the graft. Ischemic, irradiated scar tissue, bone and tendons will not have the sufficient blood supply. In such situations flaps are to be resorted. However, the flaps also need to have good vascularity over the limbs. The introduction of dermal substitutes has provided a novel method for repairing various severe skin defects. These substitutes act as dermal regenerative templates, which facilitate dermal reconstruction and regeneration. This study was done to ascertain the effectiveness of these substitutes in the treatment of complex wounds. Between January 2022 and June 2023, 20 patients who had complex wounds, which could not be treated with simple skin grafting and who were treated with collagen and elastin matrix and split skin grafting (SSG) were retrospectively studied. The percentage of SSG take as per the records was noted at a 10-day post-operative period. Patient characteristics, comorbidities, duration and outcomes of the treatment were noted. Twenty patients were included in the study. The minimum size of the ulcer was 5 × 4 cm (area of 20 cm2) and the maximum size of the ulcer was 15 × 15 cm (225 cm2). Average take of skin graft was 93.7% at 10th post-operative day. Recurrence at 6 months was nil. The scar quality was assessed by patient and observer at 3 months and 6 months post-operatively. The lower-limb ulcers with compromised surrounding tissue are complex. The major goal in these cases is to do simple surgery and prevent recurrence. The collagen and elastin matrices provide structural support for cellular infiltration, which helps maximize a SSG take and a stable long-term scar.
- MeSH
- Varicose Ulcer pathology therapy MeSH
- Elastin therapeutic use MeSH
- Collagen therapeutic use MeSH
- Middle Aged MeSH
- Humans MeSH
- Leg Injuries * pathology therapy MeSH
- Health Care Surveys methods statistics & numerical data MeSH
- Skin Transplantation * methods MeSH
- Leg Ulcer pathology therapy MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Clinical Study MeSH
Vitamin C hraje ve vývoji a funkci centrálního nervového systému celou řadu rolí. Ovlivňuje rozvoj mozku svým vlivem na epigenetiku, zajišťuje antioxidační ochranu neuronů, svou rolí při syntéze kolagenu je nepostradatelný pro tvorbu myelinových pochev a mozkových cév. Je potřebný pro syntézu neuromodulátorů, přenos signálů v centrálním nervovém systému. Dlouhodobý nedostatek vitaminu C může vést ke strukturálním změnám a funkčním poruchám v mozku. Nedostatek vitaminu C hraje významnou roli i v patogenezi neuropsychiatrických onemocnění, především deprese. Proto má zásadní význam dostatečný příjem vitaminu C těhotnými ženami i dětmi po celou dobu jejich vývoje.
Vitamin C plays a number of roles in the development and function of the central nervous system. It affects the development of the brain through the epigenetic effect, ensures antioxidant protection of neurons, and its role in the synthesis of collagen is indispensable for the formation of myelin sheaths and brain vessels. It is needed for the synthesis of neuromodulators, transmission of signals in the central nervous system. Long-term vitamin C deficiency can lead to structural changes and functional disorders in the brain. Vitamin C deficiency also plays a significant role in the pathogenesis of neuropsychiatric diseases, especially depression. Therefore, sufficient intake of vitamin C by pregnant women and by children throughout their development is of fundamental importance.
Various studies have correlated the mechanical properties of the aortic wall with its biochemical parameters and inner structure. Very few studies have addressed correlations with the cohesive properties, which are crucial for understanding fracture phenomena such as aortic dissection, i.e. a life-threatening process. Aimed at filling this gap, we conducted a comprehensive biochemical and histological analysis of human aortas (the ascending and descending thoracic and infrarenal abdominal aorta) from 34 cadavers obtained post-mortem during regular autopsies. The pentosidine, hydroxyproline and calcium contents, calcium/phosphorus molar ratio, degree of atherosclerosis, area fraction of elastin, collagen type I and III, alpha smooth muscle actin, vasa vasorum, vasa vasorum density, aortic wall thickness, thicknesses of the adventitia, media and intima were determined and correlated with the delamination forces in the longitudinal and circumferential directions of the vessel as determined from identical cadavers. The majority of the parameters determined did not indicate significant correlation with age, except for the calcium content and collagen maturation (enzymatic crosslinking). The main results concern differences between enzymatic and non-enzymatic crosslinking and those caused by the presence of atherosclerosis. The enzymatic crosslinking of collagen increased with age and was accompanied by a decrease in the delamination strength, while non-enzymatic crosslinking tended to decrease with age and was accompanied by an increase in the delamination strength. As the rate of calcification increased, the presence of atherosclerosis led to the formation of calcium phosphate plaques with higher solubility than the tissue without or with only mild signs of atherosclerosis. STATEMENT OF SIGNIFICANCE: This study presents a detailed biochemical and histological analysis of human aortic samples (ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta) taken from 34 cadavers. The contribution of this scientific study lies in the detailed biochemical comparison of the enzymatic and non-enzymatic glycosylation-derived crosslinks of vascular tissues and their influence on the delamination strength of the human aorta since, to the best of our knowledge, no such comprehensive studies exist in the literature. A further benefit concerns the notification of the limitations of the various analytical methods applied; an important factor that must be taken into account in such studies.
- MeSH
- Actins metabolism MeSH
- Aorta * metabolism MeSH
- Arginine analogs & derivatives MeSH
- Atherosclerosis metabolism pathology MeSH
- Adult MeSH
- Elastin metabolism MeSH
- Hydroxyproline metabolism MeSH
- Middle Aged MeSH
- Humans MeSH
- Lysine analogs & derivatives metabolism MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Aging * physiology MeSH
- Calcium metabolism MeSH
- Vasa Vasorum metabolism MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
nestr.
Při kardiovaskulárních operacích je často nutné používat cévní náhrady o malém průměru a tkáňové záplaty. Nejvhodnějším v tomto ohledu jsou autologní tkáně, jež je často nedostatek. Alogenní nebo umělé materiály jsou často trombogenní. Cílem projektu je vytvořit nové cévní náhrady a záplaty s využitím degradabilních kolagenních gelů vyztužených nano/mikro vlákny jež budou odlity do potřebného tvaru spolu s kmenovými buňkami. Tyto konstrukty budou remodelovány v bioreaktoru za vzniku nové tkáně. Poté bude tento konstrukt decelularizován pro eliminaci imunitní se zachováním nosné struktury. In vivo ověření v prasatech bude zahrnovat dvě operace. Při první operaci bude odebráno malé množství podkožního tuku a krev, ze kterých budou izolovány kmenové a endotelové buňky, pro autologní osídlení v bioreaktoru. Poté bude následovat druhá operace na stejném zvířeti, při které bude záplata/cévní náhrada implantována na/místo a. carotis. Po 4 týdenním klinickém monitorování budou implantáty vyjmuty a hodnocení histologicky z hlediska celkové struktury, průchodnosti a trombogenicity.; During cardiovascular surgeries are small calibre vessel grafts and vascular patches required. The most suitable in this field are autologous tissues, which are often deficient. Allogeneic or artificial materials are often thrombogenic. The aim of the project is to create vascular grafts and patches using collagen gels reinforced with nano/micro fibres, moulded into the required shape along with stem cells. These constructs will be remodelled in the bioreactor forming a new tissue. This construct will be decellularized to eliminate the immune response while retaining the support structure. In vivo verification in pigs will involve two surgeries. In the first surgery, a small amount of subcutaneous fat and blood will be collected from which stem and endothelial cells will be isolated for autologous colonization in the bioreactor. Then a second operation will be followed in which the patch/vascular replacement will be implanted onto a. Carotis. After 4 weeks of clinical monitoring, implants will be removed and histologically assessed for overall structure, patency, and thrombogenicity.
- Keywords
- mesenchymal stem cells, kolagen, nanovlákna, nanofibers, decelularizace, cévní náhrady, in vivo, in vivo, collagen, mesenchymální kmenové buňky, tukové kmenové buňky, endotelizace, vascular prostheses, adipose tissue derived stem cells, , decellularization, endothelization,
- NML Publication type
- závěrečné zprávy o řešení grantu AZV MZ ČR
The Achilles tendon (AT) is the strongest tendon of the human body. The knowledge of AT anatomy is a basic prerequisite for the successful treatment of acute and chronic lesions. The structure of the AT results from a complicated fusion of three parts: the tendons of the medial and lateral gastrocnemius and the soleus muscles. From proximal to distal, the tendon fibers twist in a long spiral into a roughly 90° internal rotation. The tendon is narrowest approximately 5-7 cm above its calcaneal insertion and from there it expands again. The topography of the footprints of the individual AT components reflects the tendon origins. The anterior (deep) AT fibers insert into the middle third of the posterior aspect of the calcaneal tuberosity, the posterior (superficial) fibers pass over the calcaneal tuberosity and fuse with the plantar aponeurosis. A deep calcaneal bursa is interposed between the calcaneal tuberosity and the AT anterior surface. The AT has no synovial sheath but is covered along its entire length with a sliding connective tissue, the paratenon which is, however, absent on its anterior surface. The AT is supplied by the posterior tibial artery (PTA) and the peroneal artery (PA). Motor innervation of the triceps surae muscle is provided by fibers of the tibial nerve which also gives off sensitive fibers for the AT. Sensitive innervation is also provided via the sural nerve. The sural nerve crosses the AT approximately 11 cm proximal to the calcaneal tuberosity. The forces acting on the AT during exercise may be up to 12 times the body weight. Physiological stretching of AT collagen fibers ranges between 2% and 4% of its length. Stretching of the tendon over 4% results in microscopic failure and stretching beyond 8% in macroscopic failure.
- MeSH
- Achilles Tendon * anatomy & histology MeSH
- Models, Anatomic MeSH
- Muscle, Skeletal anatomy & histology innervation MeSH
- Humans MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Osteochondral defects affect articular cartilage, calcified cartilage, and subchondral bone. The main problem that they cause is a different behavior of cell tissue in the osteochondral and bone part. Articular cartilage is composed mainly of collagen II, glycosaminoglycan (GAG), and water, and has a low healing ability due to a lack of vascularization. However, bone tissue is composed of collagen I, proteoglycans, and inorganic composites such as hydroxyapatite. Due to the discrepancy between the characters of these two parts, it is difficult to find materials that will meet all the structural and other requirements for effective regeneration. When designing a scaffold for an osteochondral defect, a variety of materials are available, e.g., polymers (synthetic and natural), inorganic particles, and extracellular matrix (ECM) components. All of them require the accurate characterization of the prepared materials and a number of in vitro and in vivo tests before they are applied to patients. Taken in concert, the final material needs to mimic the structural, morphological, chemical, and cellular demands of the native tissue. In this review, we present an overview of the structure and composition of the osteochondral part, especially synthetic materials with additives appropriate for healing osteochondral defects. Finally, we summarize in vitro and in vivo methods suitable for evaluating materials for restoring osteochondral defects.
- Publication type
- Journal Article MeSH
- Review MeSH
