Connective Tissue Damage Research Articles

МОРФОЛОГІЧНИЙ ПРОФІЛЬ ЮНИХ СПОРТСМЕНІВ ІЗ РІЗНИМИ ТИПАМИ ПОСТАВИ

The relevance of the research topic. The last decade in Ukraine has seen a decline in the overall health status of children. There has been an increase in the number of children with various pathological conditions: musculoskeletal disorders, various pathologies of internal organs, which, according to scientists, are mainly associated with connective tissue damage, in particular, connective tissue dysplasia. Young athletes deserve special attention, as even minor manifestations of connective tissue dysplasia can lead to serious diseases of the musculoskeletal system and other body systems during daily training and competition. The purpose of the article is to determine the morphological profile of young rugby players with different types of posture. To achieve this goal, the following research methods were used: analysis of scientific and methodological literature and documentary materials, anthropometry, and a pedagogical experiment. The results obtained in the course of the study were processed using mathematical statistics. All calculations were carried out using IBM SPSS Statistics 21 software, and graphical material was prepared in Microsoft Excel. Results. Characterising the morphological profile of young rugby players, we note that most athletes have average and above average values of body weight and chest circumference. They are characterised by harmonious physical development with a tendency to hypersthenic body constitution, with a large chest girth and a massive upper body. The search for differences between athletes with different types of posture showed that they almost do not differ in anthropometric parameters, with the exception of the lower leg circumference, which is much larger in children with scoliotic posture compared to other groups. Conclusions. It was found that rugby players already at the stage of initial training have certain deviations in posture and a rather specific morphological profile.

Histological Definition of Skeletal Muscle Injury: A Guide to Nomenclature Along the Connective Tissue Sheath/Structure.

Recent years have seen the development of various classifications of muscle injuries, primarily based on the topographic location within the bone-tendon-muscle chain. This paper proposes an enhanced nomenclature for muscle injuries that incorporates histoarchitectural definitions alongside topographic classifications, emphasizing the importance of connective tissue damage characterization. A detailed understanding of the distinct anatomical and histological characteristics of tendon, aponeurosis, and fascia is essential for consistent terminology. Tendons, aponeuroses, and fasciae, while all composed of dense connective tissue, differ in collagen fiber orientation and structural organization. Tendons feature longitudinally aligned fibers suited for high tensile forces and muscle-to-bone connections. Aponeuroses have perpendicular collagen fiber layers, allowing for force distribution and support for both longitudinal and transverse traction. Fasciae exhibit loosely organized fibers providing flexibility and movement between muscles. The continuity and differences within the musculotendinous frameworks, particularly at the musculotendinous junction (MTJ), elucidate the higher frequency of injuries at these sites compared with tendons, highlighting the MTJ's role as a stress-absorbing 'safety valve.'

Impact of Fluoroquinolones on Tendon Health: A Comprehensive Overview for the General Population and Athletes

Introduction: Fluoroquinolones are a class of broad-spectrum antibiotics widely used to treat various bacterial infections. Despite their effectiveness, increasing evidence links fluoroquinolones to tendinopathy and tendon rupture, with cases occurring shortly after initiation or even months post-therapy. This review provides a comprehensive overview of the impact of fluoroquinolones on tendon health - highlighting the underlying pathomechanisms, clinical manifestations, and epidemiology of fluoroquinolone-associated tendinopathy. Purpose of the work: The purpose of this study is to review the effects of fluoroquinolones on tendon health in the general population. Special attention is given to the athletes, who are particularly vulnerable to tendon injuries. Materials and methods: A comprehensive analysis of research articles available on PubMed, Google Scholar, Web of Science, Embase, and Scopus was conducted using search terms related to: "fluoroquinolones," "tendinopathy," "tendon rupture," "athletes" and "connective tissue damage." Results: Fluoroquinolones are linked to an increased risk of tendinopathy and tendon rupture, particularly among those with certain risk factors, including athletes. Understanding the mechanisms by which fluoroquinolones affect tendon tissue and recognizing early signs of tendon damage can help mitigate these risks. Prevention strategies, including cautious prescribing fluoroquinolones and targeted rehabilitation programmes, may reduce the adverse effects of fluoroquinolone usage, particularly in high-risk groups like athletes.

FEATURES OF THE COURSE OF GESTATION IN WOMEN WITH MITRAL VALVE PROLAPSE AGAINST THE BACKGROUND OF UNDIFFERENTIATED CONNECTIVE TISSUE DYSPLASIA

The article is devoted to the problems associated with connective tissue dysplasia (CTD), predominantly undifferentiated forms of the disease (nDST). The topic's relevance is due to the high prevalence of this pathological condition. The generalized nature of connective tissue damage with the involvement of the reproductive system in the pathological process significantly affects the course of pregnancy and Birth. Complications that may be associated with pregnancy, childbirth, and the postpartum period in women with nDST and which cause a high need for surgical aids: amnio-, episio- and perineotomy, and cesarean section are presented. Particular attention is paid to magnesium, which plays one of the determining roles in the complex biosynthesis of the extracellular matrix in the formation of connective tissue and the morphofunctional state of fibroblasts. The methods used to detect connective tissue metabolism disorders (determination of the level of oxyproline and fibronectin in blood serum, pyrinx D and glucosaminoglycans in urine, etc.) are described. Given the lack of reliable diagnostic (biochemical and genetic) criteria for nDST, special attention is paid to the need for an integrated approach to assessing the condition of patients using anamnesis data, the results of clinical, instrumental, and laboratory examinations.

Effect of Cinnamon Bark Extract (Cinnamomum Burmanii) 50% on Il-6 Levels in Gingiva of Male Wistar Rats (Rattus Norvegicus) Induced by LPS (Lipopolysaccharide)

Periodontitis is a periodontal disease in the form of chronic inflammation of the dental support tissue caused by plaque bacteria. The process of periodontal tissue damage in periodontitis begins with the accumulation of plaque containing bacteria and toxins that are pathogenic. The interaction between plaque bacteria and their products and the body's response to host cells triggers an inflammatory response that can cause ulceration of the gingiva, connective tissue damage, alveolar bone loss, and tooth loss. Periodontitis usually develops from gingivitis that has already occurred, although not all gingivitis progresses to periodontitis. The purpose of this study is to determine the effect of cinnamon bark extract on IL-6 levels. This research method used in vivo laboratory experiments on 32 white rats of the Wistar strain with a research design using a quasi-research model with a posttest only control group design which was randomized into two groups, namely the control group: induced LPS and given Tetracycline gel (Eryzol) topically, the treatment group: induced LPS and given a 50% cinnamon bark extract gel. From the comparative analysis test with the Independent T-Test, it was shown that the significant value of the decrease in IL-6 levels in each group, which was 0.194, was greater than 0.05. This means that there are differences between groups. From the results of the study, it can be said that cinnamon bark extract (Cinnamomum Burmanni) with a concentration of 50% has an effect on reducing IL-6 levels.

Механизмы поражения соединительной ткани при фибромускулярной дисплазии и атеросклерозе: возможности визуализации

Multifocality, high prevalence and lack of consensus on the etiopathogenesis of atherosclerosis and fibromuscular dysplasia (FMD) in the human population are well known. However, the issues of comorbidity and mechanisms of connective tissue damage in these pathologies remain unclear. The purpose of this study was to determine the leading causes of pathological arterial stenosis in patients with clinical signs of vascular disorders. Materials and methods. The research involved 67 patients (mean age 51.12 ± 13.12 years) with clinical signs of vascular disorders, who had received neurological or neurosurgical treatment at Surgut Clinical Trauma Hospital. The subjects underwent computed tomography angiography of brachiocephalic and intracranial vessels. To assess the internal stigmatization of the processes under study, author’s scales were developed. Results. The data of the author’s scales clearly indicate the influence of the genetically determined FMD process on the manifestations of atherosclerosis. The most frequent combinations of FMD stigmas and atherosclerotic lesions identified in the course of the study can serve as markers of the severity of these pathologies. The results allow us to view FMD and atherosclerosis in the context of morphofunctional connective tissue disorders. Paradoxically, despite the systemic nature of the two processes, their gross manifestations were clearly localized. This is probably due to the time interval of connective tissue cell damage and its nature. In our opinion, pathology in atherosclerosis develops during postnatal ontogenesis due to the increasing cytokinetic activity of connective tissue cells under the influence of various factors (atherogenic lipoproteins circulating in the vascular bed, microbiome disturbance, etc.). In FMD, fibroblasts get damaged by genetic mutations at the stage of embryonic development (vasculogenesis), gross stigmas are formed in areas of blood vessels with the most rapid growth due to the haemodynamic conditions of the onset of blood circulation (angiogenesis).

Індикативні особливості тканинної та мікробної сенсибілізації в патогенезі генералізованого пародонтиту, афілійованого з ревматоїдним артритом

Relevance. A lot of research has been devoted to the pathogenesis of generalised periodontitis, but very often researchers do not take into account the fact that generalised periodontitis often occurs against the background of internal diseases of the body, which cause not only special manifestations of the course of generalised periodontitis, but also can affect the results of its prevention and treatment. In this sense, rheumatoid arthritis, which is accompanied by chronic systemic connective tissue damage, is noteworthy. Purpose: to determine the place and integrative features of tissue and microbial sensitisation in the pathogenesis of generalised periodontitis associated with rheumatoid arthritis. Material and methods of the study. Immunological studies were performed in 335 patients divided into 3 groups: Group 1 - the main group - consisted of 136 patients with GP in the setting of RA. Group 2 - control group - 71 patients with GP diseases without signs of RA. Group 3 - comparative - 128 people without GP disease, who had musculoskeletal diseases not related to RA and practically healthy people. The periodontal condition of patients was assessed in two groups using the following parameters: Silness-Loe index (PI), bleeding index (BOP), probing pocket depth (PPD), recession level (REC), clinical attachment level (CAL) and tooth loss. To determine microbial and tissue sensitisation, the leukocyte migration inhibition reaction was used with microbial antigens of streptococci and staphylococci, and tissue antigens (bone and synovial). All the data obtained were processed by the mathematical method of variation statistics. Results of the study. In the majority of patients with GP affiliated with RA, a pronounced sensitisation to streptococcal antigen was detected, which in the chronic course of GP was 70.3±4.3%. The acute course in this group was accompanied by a high level of sensitisation in a slightly lower percentage of patients in this group and amounted to 62.5±7.0%. In the control group, the frequency of sensitised individuals to streptococcal antigen was significantly lower and amounted to 37.5±8.9 in the chronic course and 44.0±6.1 in the acute course. In practically healthy people without pathology of internal organs, musculoskeletal system and without GP disease, this indicator was only 26.0±8.0. Conclusion. The presence of microbial and tissue sensitisation in patients with GP and RA indicates that similar and cross antigens of streptococcus and staphylococcus microorganisms with connective tissue are a potential trigger for the development of both GP and RA, which is the reason to consider GP and RA as comorbid diseases with similar pathogenetic mechanisms of development. Key words: generalised periodontitis, periodontal condition, rheumatoid arthritis, sensitisation, antigen.

Histological evaluation of the surgical margins of oral soft tissue incisions using a dual-wavelength diode laser and an Er, Cr:YSGG laser; an ex vivo study.

This study compared a dual-wavelength diode laser and an Er, Cr:YSGG laser in oral soft tissue incisions to determine the most effective and safest laser system at the histopathological level. The (810 and 980 nm) dual-wavelength diode laser was used at 1.5 W and 2.5 W (CW) power settings, and the (2780 nm) Er, Cr:YSGG laser was used at 2.5 W and 3.5 W (PW) power settings. Both laser systems were used to incise the tissues of freshly dissected sheep tongue pieces to obtain the following histopathological criteria: epithelial tissue changes, connective tissue changes, and lateral thermal damage extent by optical microscopy. The epithelial and connective tissue damage scores were significantly higher in the dual-wavelength diode laser groups than in the Er, Cr:YSGG laser groups (P<0.001), and there was a significant difference between some groups. The extent of lateral thermal damage was also significantly higher in the diode laser groups than in the Er, Cr: YSGG laser groups (P<0.001), and there was a significant difference between groups. Group 2 (2.5 W) of the diode laser was the highest for all three criteria, while group 3 (2.5 W) of the Er, Cr:YSGG laser was the lowest. The Er, Cr:YSGG laser with an output power of 2.5 W is, histologically, the most effective and safest laser for oral soft tissue incision. The dual-wavelength diode laser causes more damage than the Er, Cr:YSGG laser, but it can be used with a low output power and 1 mm safety distance in excisional biopsy.

The ginsenoside Rg2 downregulates MMP-1 expression in keratinocyte (HaCaT)-conditioned medium-treated human fibroblasts (Hs68)

Keratinocytes exposed to UVB induce the production of cytokines, which activate fibroblasts and increase the expression of matrix metalloproteinases (MMPs). The increased expression of MMPs leads to connective tissue damage and wrinkle formation, resulting in skin aging. In this study, we used human dermal fibroblasts cultured in UVB-irradiated keratinocyte-conditioned medium (UV CM) to investigate the potential anti-aging effects of the ginsenoside Rg2 on skin. The inhibitory effect of Rg2 on the MMP-1 gene and protein was determined by real-time PCR and ELISA. We also examined the expression levels of proteins in the mitogen-activated protein kinase (MAPK) signaling pathway using western blotting, to elucidate the underlying mechanism of the inhibitory effect of Rg2. Rg2 inhibited MMP-1 mRNA and protein expression in a concentration-dependent manner. We found that Rg2 inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) but not that of p38. Therefore, our results suggest that Rg2 is a potential material for the prevention and treatment of photoaging.

Delayed Onset Muscle Soreness (DOMS): Management Update

Delayed Onset Muscle Soreness (DOMS) is a prevalent issue in sports medicine and among physically active individuals, causing significant pain and disability. While the exact pathophysiology of DOMS remains incompletely understood, this article delves into non-pharmacological approaches to effectively manage and alleviate its symptoms.&#x0D; The research discusses multifaceted aspects of DOMS, encompassing its complex etiology, theories, and contributing factors. Numerous theories have been proposed, including delayed inflammatory responses, lactic acid accumulation, muscle spasms, connective tissue damage, and muscle micro-tears. These theories underscore the intricate nature of DOMS and the need for a diverse management approach.&#x0D; The article explores non-pharmacological strategies to address DOMS, focusing on evidence-based methods. These methods include massage, exercise, nutrition, and natural supplements. Research has shown that massage therapy enhances muscle recovery, exercise therapy reduces soreness, and nutrition therapy through protein and amino acid intake can alleviate DOMS. Furthermore, natural supplements like ginger, tart cherry juice, and curcumin have demonstrated the potential to reduce inflammation and manage DOMS.&#x0D; While pharmacological interventions may be considered for severe cases, the article underscores the importance of exercising caution due to potential side effects. In summary, DOMS management necessitates a holistic approach, combining multiple modalities and nutritional strategies to alleviate pain, enhance muscle recovery, and minimize the impact of this common condition on physically active individuals and athletes.

Editorial: The effect of Cyriax method on the treatment of Lateral Elbow Tendinopathy

Lateral elbow tendinopathy (LET) is the most common chronic disease of the elbow joint [1], affecting almost 1-3% of the general [2, 3]. Its incidence increases with age and is highest in the 35-60 age group [2, 4]. Extensor carpi radialis brevis’ tendon is the most common structure affected by LET [5]. There is a continuous cycle of minor injuries and constant attempts to repair the damage, causing in progressive degeneration [6,7]. Consequently, a domino effect of changes occurs in the peripheral nervous system neurons, ultimately resulting to the sensitization of the central nervous system [3, 8]. Treatment for LET includes a wide variety of techniques, due to the complexity of the condition. Scientific evidence on the efficacy of the various techniques is of poor quality [9], which hampers the choice of the right therapeutic plan [10, 11]. The Cyriax method was empirically developed by James Cyriax as a therapeutic approach to connective tissue damage [12]. It is an inseparable combination of deep transverse friction (DTF) and Mill’s manipulation [13, 14]. This approach aims to the passive mobilization of soft tissues, preparing them to endure load. The regenerative process is boosted and the mobility of the damaged tissue is restored through pain reduction [12, 14]. Despite the fact that clinical experience supports the use of Cyriax method on LET, the results of systematic reviews show that it is not superior to other approaches indicated for this condition [15-17]. At the same time, there is no consensus on how to apply the method, which leads to a lack of standardization of the relative protocols [12]. In addition, great diversity is observed in the methodological design, the instruments and methods of evaluating the variables (pain, functionality) [12]. The disagreement on DTF procedures and the awareness that physiotherapists’ performance may be affected by the lack of understanding of Cyriax’s conclusions motivated the development of this thesis: The primary aim is to analyze the application parameters of the Cyriax method, as well as its effect on the symptoms of LET, by documenting how physiotherapists in Greece use the method. Moreover, and in line with the latest findings [18], a psychometric evaluation of LET will be included in this thesis. Kinesiophobia is an outcome measure that should be considered, as it is affected by LET [18-20].

Analysis of the toxic effects of fluoroquinolones in laboratory rabbit models

Introduction. Fluoroquinolones are antibacterials for which the development of cardiotoxicity, hepatotoxicity, nephrotoxicity and connective tissue damage has been noted. The likely mechanism for the development of these reactions is magnesium metabolism disorder. An available method to detect fluoroquinolones toxicity in animal experiments is a blood biochemical test.The aim of the work was to identify the biochemical signs of the toxic effects of fluoroquinolones in laboratory rabbit models.Materials and methods. Twenty male rabbits randomised into three groups were included in the study: 6 control animals; 7 rabbits treated with ciprofloxacin 150 mg/kg 14 days; 7 rabbits treated with levofloxacin 150 mg/kg 14 days. Serum levels of albumin, alanine aminotransferase (liver damage marker), creatinine (nephrotoxicity marker), creatine kinase MB (cardiotoxicity marker), matrix metalloproteinase 9 (connective tissue damage marker), serum and plasma magnesium content were studied in this work. Data are presented as mean (standard deviation).Results. Serum levels of albumin, alanine aminotransferase and creatinine did not change during the experiment. Rabbits treated with levofloxacin had 2.0–2.5 times lower values of CF creatine kinase activity than control animals. There was double increase of serum concentration of matrix metalloproteinase 9 in ciprofloxacin group in comparison with control (70,17 (20,88) and 38,10 (16,04) ng/ ml, p = 0,019). Magnesium content was unchanged with both fluoroquinolones.Discussion. The absence of signs of hepatotoxicity and nephrotoxicity is consistent with their low frequency of detection in clinical and experimental studies. A decrease in the activity of creatine kinase MB in animals treated with levofloxacin has not been described in the literature. An increase in the concentration of metalloproteinase 9 is evidence of destruction of connective tissue structures. The absence of changes in serum and plasma concentrations of magnesium is explained by the functioning of the systems maintaining the constancy of its content in blood.Conclusion. No biochemical evidence of hepato-, nephro- and cardiotoxic effects of ciprofloxacin and levofloxacin at the doses of 150 mg/kg for 14 days was shown in rabbits; no magnesium metabolism disorders were shown, and the ability of ciprofloxacin to increase the serum content of matrix metalloproteinase type 9 was demonstrated. The proposed model can be used to investigate ways to prevent the toxic effects of fluoroquinolones on connective tissue structures.

In vitro Anti-Inflammatory Egg Albumin Denaturation Assay: An Enhanced Approach

As a physical reaction to injury, infection, or destruction, inflammation is characterized by heat, redness, discomfort, swelling, and abnormal physiological processes. The inflammatory process is a complicated series of relationships among soluble substances and cellular elements that frequently include connective tissue damage. An uncontrolled inflammatory response is the primary cause of a wide range of disorders, including allergies, cardiovascular dysfunctions, metabolic syndrome, cancer, and autoimmune diseases, placing a significant financial burden on individuals and, in turn, on society. Steroids, nonsteroid anti-inflammatory drugs, and immunosuppressants are some examples of common medications for controlling and suppressing inflammatory crises; but they have several side effects, particularly stomach irritation that can cause gastric ulcers. Using natural goods has had a significant positive impact on the development of modern medicine. On such background, plants have historically been an excellent source of medication, and there are several records on the use of herbs in traditional medicine to treat a variety of inflammatory illnesses. However, there has been no scientific attempt to verify these spontaneous uses reported in the literature. Therefore, to conduct more studies and gather more data, scientists need to develop low-cost, straightforward in vitro methodologies to assess the efficacy of natural anti-inflammatory compounds. With this context in mind, this methodology focuses on in vitro anti-inflammatory methodology that can be used to evaluate natural anti-inflammatory substances. They are cost-effective, easy to operate, and dependable with minor alterations.

Особенности диагностики и лечения глаукомы у лиц молодого возраста

Purpose. To reveal the features of diagnosis and treatment of glaucoma in a group of young patients. Material and methods. Complex ophthalmological examination of 10 young patients diagnosed with glaucoma. Among them, three are on conservative treatment, the rest underwent non-penetrating deep sclerectomy with Xenoplast drainage implantation. Results. Patients who have undergone surgical treatment, especially in the early stages of glaucoma, are able to stabilize the pathological process, while maintaining visual functions at a high level. In an unoperated patient with myopia and nNDST, on maximum antihypertensive therapy, a negative trend was noted according to OCT. In the only case, a patient with emmetropia has stable indicators for several years on drug treatment (prostaglandin analogues). Conclusion. Timely diagnosis and implementation of nonpenetrating deep sclerectomy in the early stages are the main links in the successful treatment of young glaucoma. Patients with axial myopia and glaucoma should be evaluated cardiologically and orthopedically for signs of connective tissue damage. Undifferentiated connective tissue dysplasia may be the pathophysiological basis of the glaucoma process. Key words: glaucoma of a young age, inherited disorders of connective tissue, juvenile glaucoma

Histopathological Characterization of Abdominal Aortic Aneurysms from Patients with Multiple Aneurysms Compared to Patients with a Single Abdominal Aortic Aneurysm.

The aim of this study was to investigate histopathological differences in abdominal aortic aneurysms (AAAs) between patients with multiple and single arterial aneurysms, as we suspect that there are different underlying mechanisms in aneurysm formation. Analysis was based on a previous retrospective study on patients with multiple arterial aneurysms (mult-AA; defined as at least four, n = 143) and a single AAA (sing-AAA, n = 972) who were admitted to our hospital for treatment between 2006 and 2016. Available paraffin-embedded AAA wall specimens were derived from the Vascular Biomaterial Bank Heidelberg (mult-AA, n = 12 vs. sing-AAA, n = 19). Sections were analyzed regarding structural damage of the fibrous connective tissue and inflammatory cell infiltration. Alterations to the collagen and elastin constitution were assessed by Masson-Goldner trichrome and Elastica van Gieson staining. Inflammatory cell infiltration, response and transformation were assessed by CD45 and IL-1β immunohistochemistry and von Kossa staining. The extent of aneurysmal wall alterations was assessed by semiquantitative gradings and was compared between the groups using Fisher's exact test. IL-1β was significantly more present in the tunica media in mult-AA compared to sing-AAA (p = 0.022). The increased expression of IL-1β in mult-AA compared to sing-AAA indicates inflammatory processes play a role in aneurysm formation in patients with multiple arterial aneurysms.

Effects of tissue degradation by collagenase and elastase on the biaxial mechanics of porcine airways

BackgroundCommon respiratory illnesses, such as emphysema and chronic obstructive pulmonary disease, are characterized by connective tissue damage and remodeling. Two major fibers govern the mechanics of airway tissue: elastin enables stretch and permits airway recoil, while collagen prevents overextension with stiffer properties. Collagenase and elastase degradation treatments are common avenues for contrasting the role of collagen and elastin in healthy and diseased states; while previous lung studies of collagen and elastin have analyzed parenchymal strips in animal and human specimens, none have focused on the airways to date.MethodsSpecimens were extracted from the proximal and distal airways, namely the trachea, large bronchi, and small bronchi to facilitate evaluations of material heterogeneity, and subjected to biaxial planar loading in the circumferential and axial directions to assess airway anisotropy. Next, samples were subjected to collagenase and elastase enzymatic treatment and tensile tests were repeated. Airway tissue mechanical properties pre- and post-treatment were comprehensively characterized via measures of initial and ultimate moduli, strain transitions, maximum stress, hysteresis, energy loss, and viscoelasticity to gain insights regarding the specialized role of individual connective tissue fibers and network interactions.ResultsEnzymatic treatment demonstrated an increase in airway tissue compliance throughout loading and resulted in at least a 50% decrease in maximum stress overall. Strain transition values led to significant anisotropic manifestation post-treatment, where circumferential tissues transitioned at higher strains compared to axial counterparts. Hysteresis values and energy loss decreased after enzymatic treatment, where hysteresis reduced by almost half of the untreated value. Anisotropic ratios exhibited axially led stiffness at low strains which transitioned to circumferentially led stiffness when subjected to higher strains. Viscoelastic stress relaxation was found to be greater in the circumferential direction for bronchial airway regions compared to axial counterparts.ConclusionTargeted fiber treatment resulted in mechanical alterations across the loading range and interactions between elastin and collagen connective tissue networks was observed. Providing novel mechanical characterization of elastase and collagenase treated airways aids our understanding of individual and interconnected fiber roles, ultimately helping to establish a foundation for constructing constitutive models to represent various states and progressions of pulmonary disease.

Relative motion between the flexor digitorum superficialis tendon and subsynovial connective tissue is time dependent.

The subsynovial connective tissue is an integral component of flexor tendon gliding in the carpal tunnel, which is strained during longitudinal tendon displacement. We tested the effects of repetition frequency and finger load on flexor tendon function throughout active finger movement. Eleven participants performed metacarpophalangeal joint flexion/extension of the long finger cyclically at three repetition frequencies (0.75, 1.00, 1.25 Hz) and two finger loads (3.5, 7 N). Relative displacement between the flexor digitorum superficialis tendon and subsynovial connective tissue was assessed as the shear-strain index with color ultrasound throughout the entire time history of finger flexion and extension. In addition, long finger joint angles were measured with electrogoniometry while flexor digitorum superficialis and extensor digitorum muscle activities were measured with fine-wire electromyography to characterize the finger movements. The shear-strain index increased with greater finger flexion (p = 0.001), representing higher relative displacement between tendon and subsynovial connective tissue; however, no changes were observed throughout finger extension. The shear-strain index also increased with higher repetition frequencies (p = 0.013) and finger loads (p = 0.029), further modulating time-dependent effects during finger flexion versus extension. Using ultrasound, we characterized the time-dependent response of the shear-strain index, in vivo, providing valuable data on flexor tendon function during active finger movement. Our results infer greater subsynovial connective tissue strain and shear during repetitive and forceful finger movements. Future research characterizing time-dependent effects in carpal tunnel syndrome patients may further elucidate the relations between subsynovial connective tissue function, damage, and carpal tunnel syndrome.

Epidemiology of hamstring injuries in 538 cases from an FC Barcelona multi sports club

ABSTRACT Objectives Hamstring injuries are the most common muscle injuries in team sports. The aims of this study were to describe the epidemiology of hamstring muscle injuries in the professional and amateur sport sections of a multi-sport club Football Club Barcelona (FCB) and to determine any potential correlation between return-to-play (RTP) and injury location, severity of connective tissue damage, age, sex, and athlete’s level of competition. Methods This descriptive epidemiological study with data collected from September 2007 to September 2017 stored in the FCB database. The study included non-contact hamstring injuries sustained during training or competition. Results A total of 538 hamstring injuries were reported in the club’s database, of which 240 were structurally verified by imaging as hamstring injuries. The overall incidence for the 17 sports studied was 1.29 structurally verified hamstring injuries per 100 athletes per year. The muscle most commonly involved in hamstring injuries was the biceps femoris, and the connective tissue most frequently involved was the myofascial. There was no evidence of a statistically significant association between age and RTP after injury, and no statistically significant difference between sex and RTP. However, the time loss by professionals was shorter than for amateurs, and proximal hamstring injuries took longer RTP than distal ones. Conclusion In the 17 sports practiced at multi-sport club, the incidence of hamstring injury was 1.29 per 100 athletes per year. Players from sports in which high-speed sprinting and kicking are necessary, and amateurs, were at higher risk of suffering a hamstring injury. In addition, proximally located hamstring injuries involving tendinous connective tissue showed the longest RTP time. Age did not seem to have any influence on RTP. Documenting location and the exact tissue involved in hamstring injuries may be beneficial for determining the prognosis and RTP.

Possibilities of multiphoton microscopy for the diagnosis of the vulvar lichen sclerosus

Vulvar lichen sclerosus (VLS) is a chronic and recurrent dermatosis of an inflammatory nature with severe focal atrophy of the skin. Connective tissue changes are polymorphic and are still not taken into account in histological diagnostics due to the difficulty of interpreting routine histological methods. In this work, we use multiphoton microscopy (MPM) as a new imaging technique that provides detailed information about the organization of collagen fibers in the dermis based on a non-linear second harmonic generation (SHG) process. To determine the degree of connective tissue damage in lichen sclerosus using standard histological techniques and to reveal the diagnostic capabilities of multiphoton microscopy. We studied 42 biopsies with a histopathological diagnosis of VLS and 10 biopsies of normal vulvar skin. Histological, histochemical and immunohistochemical evaluation was used in comparison with MPM data. Quantitative analysis included the determination of the thickness, length of collagen fibers and the average intensity of the SHG signal. A comprehensive study of the skin showed 4 groups of changes that can be regarded as the degree of the dermis damage: initial, mild, moderate, severe. The affected area at the initial and mild degree has subtle changes, however, it is reliably identified by quantitative analysis of the SHG signal. So, the initial degree is characterized by thin (1.3-1.8 µm) long (56-69 µm) collagen fibers, with a moderate degree, the fibers are thickened (3.4-4.3 µm) and fragmented (22-37 µm). The affected area in moderate and severe cases undergoes homogenization, which is associated with the deposition of extremely thin (0.6-0.9 μm) short (16-28 μm) collagen fibers and the expression of type V collagen. Multiphoton microscopy in the second harmonic generation mode is a reliable method for identifying collagen fibers in tissues. The study made it possible to identify 4 degrees of the dermis damage in vulvar lichen sclerosus.

Clinical and therapeutic course in head variants of linear morphea in adults: a retrospective review

Parry Romberg Syndrome (PRS) and en coup de sabre (ECDS) are head variants of linear morphea with functional and structural implications. This study describes the clinical course, autoimmune co-morbidities, complications, and treatment of adults with PRS/ECDS at a tertiary referral center. We retrospectively reviewed the records of all 34 adult patients with PRS/ECDS identified through billing code search and seen by dermatologists at our institution between 2015 and 2021. Eight patients (23.5%) had ECDS, 8 (23.5%) had PRS, and 18 (52.9%) had overlap. Twenty-six patients (76.5%) reported ocular, oral, and/or neurologic symptoms, and 8 (23.5%) had concomitant autoimmune/inflammatory conditions. Sixteen patients (47.1%) had a skin biopsy, and 25 (73.5%) had imaging. Forty-six MRIs were obtained, of which 6 (13.0%) reported intracranial findings and 25 (54.3%) reported disease-related connective tissue damage. Twenty-four patients (70.6%) underwent systemic treatment during their disease course per available clinical records. Seventeen patients (70.8%) had improved or stable disease upon treatment completion, with an average duration of 22.2 months. Ten patients (41.7%) reported recurrence of disease following the treatment course. To address changes to facial contour, 6 patients (17.6%) opted for procedural treatments. One patient (16.7%) experienced morphea reactivation following a filler injection performed off-immunosuppression. Compared to findings in children, our study suggests adults with PRS/ECDS are more likely to have oral and ocular complications but experience less severe neurologic symptoms. While systemic treatments appear beneficial in most adult patients with PRS/ECDS, disease may recur following discontinuation.