Are There Any Differences in the Healing Capacity between the Medial Collateral Ligament's (MCL) Proximal and Distal Parts in the Human Knee? Quantitative and Immunohistochemical Analysis of CD34, α-Smooth Muscle Actin (α-SMA), and Vascular Endothelial Growth Factor (VEGF) Expression Regarding the Epiligament (EL) Theory.

The human knee is a complex joint that comprises several ligaments, including the medial collateral ligament (MCL). The MCL provides stability to the knee and helps prevent its excessive inward movement. The MCL also has a thin layer of connective tissue known as the epiligament (EL), which adheres to the ligament. This unique feature has drawn attention in the field of ligament healing research, as it may have implications for the recovery process of MCL injuries. According to the EL theory, ligament regeneration relies heavily on the provision of cells, blood vessels, and molecules. The present study sought to compare the expression of vascular endothelial growth factor (VEGF), CD34, and α-smooth muscle actin (α-SMA) in healthy knees' proximal and distal MCL segments to better understand how these proteins affect ligament healing. By improving the EL theory, the current results could lead to more effective treatments for ligament injury. To conduct the present analysis, monoclonal antibodies were used against CD34, α-SMA, and VEGF to examine samples from 12 fresh knee joints' midsubstance MCLs. We identified a higher cell density in the EL than in the ligament connective tissue, with higher cell counts in the distal than in the proximal EL part. CD34 immunostaining was weak or absent in blood vessels and the EL, while α-SMA immunostaining was strongest in smooth muscle cells and the EL superficial layer. VEGF expression was mainly in the blood vessels' tunica media. The distal part showed more SMA-positive microscopy fields and higher cell density than the proximal part (4735 vs. 2680 cells/mm2). Our study identified CD34, α-SMA, and VEGF expression in the MCL EL, highlighting their critical role in ligament healing. Differences in α-SMA expression and cell numbers between the ligament's proximal and distal parts may explain different healing capacities, supporting the validity of the EL theory in ligament recovery.

Squamous Cell Carcinoma of the Thumb: A Case Report.

Squamous cell carcinoma (SCC) is the most common tumor of the hand with a high tendency for local recurrence and a low rate of metastasis. Herein, we present an interesting case of SCC of the thumb of the right hand in a 68-year-old patient with one recurrence, treated with surgical excision and following radiotherapy. Five years postoperative, there are no clinical and imaging data for local recurrence, as well as the presence of metastases. We also make a brief review of the current literature on this neoplasia.

Do the Differences in the Epiligament of the Proximal and Distal Parts of the Anterior Cruciate Ligament Explain Their Different Healing Capacities? Quantitative and Immunohistochemical Analysis of CD34 and α-SMA Expression in Relation to the Epiligament Theory.

The aim of this study was to assess the epiligament theory by determining the normal epiligament morphology of the proximal and distal parts of the anterior cruciate ligament in humans and analyzing the differences between them and the midportion of the ligament in terms of cell numbers and expression of CD34 and α-SMA. Samples were obtained from the anterior cruciate ligaments of 12 fresh knee joints. Monoclonal antibodies against CD34 and α-SMA were used for immunohistochemistry. Photomicrographs were analyzed using ImageJ software, version 1.53f. The cell density was higher in the epiligament than in the ligament connective tissue. Cell counts were higher in the proximal and distal thirds than in the midsubstance of the epiligament. CD34 was expressed similarly in the proximal and distal thirds, although it seemed slightly more pronounced in the distal third. α-SMA expression was more robust in the proximal than the distal part. The results revealed that CD34 and α-SMA are expressed in the human epiligament. The differences between the numbers of cells in the proximal and distal parts of the epiligament and the expression of CD34 and α-SMA enhance epiligament theory. Future investigations into improving the quality of ligament healing should not overlook the epiligament theory.

Role of Elevated Serum TGF-ß1 and the Common Promoter TGFB1-509C/T Polymorphism in the Development and Progression of Primary Glial Tumors and Brain Metastases.

Background and Objectives: The role of transforming growth factor-beta1 (TGF-ß1) has been widely studied in the context of carcinogenesis. It has been involved in the pathogenesis of primary brain tumors or brain metastases due to its pleiotropic effects on immune regulation and tissue homeostasis. In line with recent findings, the aim of the current study was to examine the role of circulating TGF-ß1 and the -509C/T functional polymorphism (rs1800469) in the TGFB1 gene promoter in the susceptibility and progression of primary brain tumors and brain metastases among patients from the Bulgarian population. Materials and Methods: Cases with a confirmed diagnosis were genotyped by the polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). Serum TGF-ß1 levels were determined by ELISA. Immunohistochemical evaluation of the expression of TGF-ß1 and the TGF-ß1 receptor-type II was conducted. Results: We observed that TGF-ß1 serum levels correlate with the genotype and are sex-related. TGF-ß1 serum levels were significantly elevated in patients compared to controls. Additionally, the T/T-genotype determined higher circulating levels of the cytokine. The same genotype determined the shorter median survival after surgery for the patients. The immunohistochemical analysis revealed a statistical tendency: cases expressing TGF-ß1 in the cytoplasm had elevated levels of the cytokine in the serum compared to the negative cases. Conclusions: Overall, our results indicate a negative effect of the T-allele on the predisposition and prognosis of brain malignancies, and the genetically determined higher TGF-ß1 serum levels might contribute to the worse prognosis and metastatic capacity of brain malignancies.

COVID-19 Complications: Oxidative Stress, Inflammation, and Mitochondrial and Endothelial Dysfunction.

SARS-CoV-2 infection, discovered and isolated in Wuhan City, Hubei Province, China, causes acute atypical respiratory symptoms and has led to profound changes in our lives. COVID-19 is characterized by a wide range of complications, which include pulmonary embolism, thromboembolism and arterial clot formation, arrhythmias, cardiomyopathy, multiorgan failure, and more. The disease has caused a worldwide pandemic, and despite various measures such as social distancing, various preventive strategies, and therapeutic approaches, and the creation of vaccines, the novel coronavirus infection (COVID-19) still hides many mysteries for the scientific community. Oxidative stress has been suggested to play an essential role in the pathogenesis of COVID-19, and determining free radical levels in patients with coronavirus infection may provide an insight into disease severity. The generation of abnormal levels of oxidants under a COVID-19-induced cytokine storm causes the irreversible oxidation of a wide range of macromolecules and subsequent damage to cells, tissues, and organs. Clinical studies have shown that oxidative stress initiates endothelial damage, which increases the risk of complications in COVID-19 and post-COVID-19 or long-COVID-19 cases. This review describes the role of oxidative stress and free radicals in the mediation of COVID-19-induced mitochondrial and endothelial dysfunction.

Vitamin E and Silymarin Reduce Oxidative Tissue Damage during Gentamycin-Induced Nephrotoxicity.

Aminoglycoside antibiotics and gentamicin (GN), in particular, are still widely used in clinical practice. It is a well-known fact that GN causes nephrotoxicity, and redox disturbances are discussed as a factor in its side effects. Recently, a new type of cell oxidative death, named ferroptosis, was discovered; it is associated with iron accumulation in the cell, glutathione (GSH) depletion and inactivation of glutathione peroxidase-4 (GPX4), reactive oxygen species (ROS) increment with concomitant lipid peroxidation. In this regard, a possible connection between GN-induced renal damage, ferroptosis and the overall antioxidant status of the organism could be investigated. Moreover, due to its beneficial effects, GN is still one of the main choices as a therapeutic agent for several diseases, and the possible reduction of its side effects with the application of certain antioxidants will be of important clinical significance. The study was conducted with adult male white mice divided into several groups (n = 6). GN nephrotoxicity was induced by the administration of GN 100-200 mg/kg i.p. for 10 days. The control group received only saline. The other groups received either Vitamin E (400 mg/kg p.o.) or Silymarin (200 mg/kg p.o.) applied alone or together with GN for the same period. After the end of the study, the animals were sacrificed, and blood and tissue samples were taken for the assessment of biochemical parameters and antioxidant status, as well as routine and specific for GPX4 histochemistry examination. The experimental results indicate that GN-induced nephrotoxicity negatively modulates GPX4 activity and is associated with increased production of ROS and lipid peroxidation. The groups treated with antioxidants demonstrated preserved antioxidant status and better GPX4 activity. In conclusion, the inhibition of ROS production and especially the suppression of ferroptosis, could be of clinical potential and can be applied as a means of reducing the toxic effects of GN application.

Case Report: Spontaneous Left Inferior Epigastric Artery Injury in a COVID-19 Female Patient Undergoing Anticoagulation Therapy.

Since the beginning of the pandemic, a recommendation was made for the use of anticoagulants in high-risk hospitalized patients. This therapeutic approach has positive and negative effects regarding the outcome of the disease. Anticoagulant therapy prevents thromboembolic events, but it can also lead to spontaneous hematoma formation, or be accompanied by massive active bleeding. We present a 63-year-old COVID-19-positive female patient with a massive retroperitoneal hematoma and spontaneous left inferior epigastric artery injury.

Protective Role of IL7A-197 A/G Heterozygosity in the Development and Severity of Colorectal Cancer in the Bulgarian Population.

Background: Interleukin (IL)-17A and IL-17F, expressed mainly by a novel subset of CD-positive (+) T-helper (Th) cells of the immune system, has been closely related to inflammatory conditions underlying colorectal cancer pathogenesis. Accordingly, we conducted a case-control study to investigate the association of common single nucleotide polymorphisms (SNP) in the IL17A and IL17F genes (rs2275913 and rs763780, respectively) with the susceptibility and severity of CRC patients from the Bulgarian population. Methods and Materials: 136 patients with histologically confirmed CRC diagnosis and 116 healthy individuals were recruited in the present study. Genotypes were determined by the restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique. Results: The IL17A heterozygous A/G-genotype was overrepresented among the control group (p = 0.003). Additionally, the carriers of the heterozygous A/G-genotype had a 2.39-fold lower risk for CRC compared to the G/G-genotype (OR = 0.418, p = 0.006). Our results also indicated that in the advanced CRC stages (III + IV) the heterozygous genotype (A/G) appeared to be less frequent (p = 0.024, χ2-test). Among the patients with detected distant metastases, the A/G-carriers were the smallest part (14.3%) compared to the homozygous genotypes A/A (42.9%) and G/G (42.8%), p = 0.006. There was no association of the studied IL17F rs763780 SNP with susceptibility and severity of CRC among the studied subjects, although the heterozygous C/T-carriers had shorter median survival compared to the T/T-carriers (p = 0.129). Conclusions: Our study finds a protective role of heterozygosity for the IL17A-197A/G SNP and negative effects of the A-allele on CRC progression.

The Azadirachta indica (Neem) Seed Oil Reduced Chronic Redox-Homeostasis Imbalance in a Mice Experimental Model on Ochratoxine A-Induced Hepatotoxicity.

Liver damage severity depends on both the dose and the exposure duration. Oxidative stress may increase the Ochratoxine-A (OTA) hepatotoxicity and many antioxidants may counteract toxic liver function. The present study aims to investigate the hepatoprotective potential of Azadirachta indicaA (A. indica; neem oil) seed oil to reduce acute oxidative disorders and residual OTA toxicity in a 28-day experimental model. The activity of antioxidant and hepatic enzymes, cytokines and the levels of oxidative stress biomarkers -MDA, GSPx, Hydroxiproline, GST, PCC, AGEs, PGC-1, and STIR-1 were analyzed by ELISA. The free radicals ROS and RNS levels were measured by EPR. The protective effects were studied in BALB/C mice treated with A. indica seed oil (170 mg/kg), alone and in combination with OTA (1.25 mg/kg), by gavage daily for 28 days. At the end of the experiment, mice treated with OTA showed changes in liver and antioxidant enzymes, and oxidative stress parameters in the liver and blood. A. indica oil significantly reduced oxidative stress and lipid peroxidation compared to the OTA group. In addition, the hepatic histological evaluation showed significant adipose tissue accumulation in OTA-treated tissues, while treatment with 170 mg/kg A. indica oil showed moderate adipose tissue accumulation.

A comparative study of the epiligament of the medial collateral and anterior cruciate ligaments in the human knee: Immunohistochemical analysis of CD 34, α-smooth muscle actin and vascular endothelial growth factor in relation to epiligament theory.

BACKGROUND: This study evaluated and compared the expression of VEGF, CD34, and α-SMA in the anterior cruciate ligaments and medial collateral ligaments in healthy human knees in order to enrich the epiligament theory regarding ligament healing after injury. METHODS: Samples from the mid-substance of the anterior cruciate ligament and the medial collateral ligament of 12 fresh knee joints were used. Monoclonal antibodies against CD34, α-SMA, and VEGF were used for immunohistochemical analysis. Photomicrographs were analyzed using the ImageJ software. RESULTS: The epiligament of the anterior cruciate ligament showed slightly higher expression of CD34, α-SMA, and VEGF than the epiligament of the medial collateral ligament. Overall, among the tested markers, α-SMA expression was most pronounced in anterior cruciate ligament epiligament images and CD34 dominated in medial collateral ligament epiligament images. The intensity of DAB staining for CD34, α-SMA, and VEGF was higher in vascular areas of the epiligament than in epiligament connective tissue. CONCLUSIONS: The results illustrate that CD34, α-SMA, and VEGF are expressed in the human epiligament. The differences between the epiligament of the investigated ligaments and the fact that CD34, α-SMA, and VEGF, which are known to have a definite role in ligament healing, are predominantly expressed in the main vascular part of the ligament-epiligament complex enlarge the existing epiligament theory. Future investigations regarding better ligament healing should not overlook the epiligament tissue.

Paroxysmal Finger Hematoma-A Probable Vascular Disorder in Post-COVID-19 Condition: Two Clinical Case Presentations.

Background and Objectives: Achenbach's syndrome is usually a benign, self-limiting clinical condition presented with finger discoloration, pain, and edema. Etiology, pathogenesis, and incidence remain unknown due to the variety of clinical features and the diversity of disease states leading to digital ischemia. COVID-19 primarily affects microcirculation, causing endothelial damage and disseminated microthrombosis. Materials and Methods: We reviewed two cases of Caucasian women with Achenbach's syndrome after COVID-19 infection recovery between April and May 2021. Results: Here are presented two extremely rare cases of paroxysmal finger hematoma in two female patients after COVID-19 infection recovery. Conclusions: The exact etiology and pathophysiology of Achenbach's syndrome remain unclear. It is assumed that SARS-CoV-2 infection could be the triggering factor in the pathophysiological mechanism of paroxysmal finger hematoma. We highly recommend the implication of the synthetic prostacyclin receptor agonist (Iloprost) as a first-line conservative treatment in patients with Achenbach's syndrome and COVID-19 infection recovery.

Strengthening CoViD-19 therapy via combinations of RAS modulators.

Evidence has accumulated that the pathology of CoViD-19 is strongly related to the renin-angiotensin system (RAS). The blockage of the angiotensin converting enzyme 2 (ACE2) by the SARS-CoV-2 virus leads to downstream consequences such as increased vascular tone, extensive fibrosis and pronounced immune reactions. Different approaches to tackle the adverse viral effects by compensating the lost ACE2 function have been suggested. Here, we use an unequal-arm lever model to describe a simplified version of the biased regulation exercised by the angiotensin II and angiotensin-(1-7) hormones, which are the substrate and the product of ACE2, respectively. We reason upon the lever dynamics and its disruptions caused by the virus, and propose that a combination of RAS modulators will most efficiently compensate the imbalance due to the excess of angiotensin II and the scarcity of angiotensin-(1-7). Specifically, we focus on the possible benefits of the simultaneous application of two agents, a MAS-receptor agonist and an angiotensin-II-type-2-receptor agonist. We conjecture that this combination has the potential to introduce a beneficial synergistic action that promotes anti-hypoxic, anti-fibrotic and anti-proliferative effects, thereby improving the clinical management of acute and chronic CoViD-19 pathologies.

Fructose-induced metabolic disturbances in rats and its impact on stomach endocrine cell number and smooth muscle contractility.

Context: Gastric ghrelin-positive endocrine cells (GHR + EC) were most dense in the oxyntic mucosa.Objective: We evaluated ECs and contractile activity in rat stomach with metabolic disorders.Materials and methods: Male Wistar rats were divided into two groups: Control (n = 9) received tap water and Fructose (n = 9) drank 15% fructose solution for 12 weeks. Streptozotocin was applied in a dose of 20 mg/kg b.w. two weeks after the beginning of the experiment on Fructose group. Smooth-muscle strips from the stomach were influenced by Angiotensin II for analysis of parameters of contractions. Stomach samples were elaborated with immunohistochemistry for ghrelin, somatostatin, gastrin antibodies and with double immunofluorescence.Results: In treated animals, GHR + EC were significantly increased in the corpus where somatostatin-positive cells were decreased. Contractile activity was decreased.Conclusions: The increase number of GHR + EC was discussed in the context of Somatostatin and Gastrin-positive ECs variations and correlated with the decrease of smooth muscle contraction.

IL-6 Activities in the Tumour Microenvironment. Part 1.

The predominant role of IL-6 in cancer is its key promotion of tumour growth. IL-6 binds IL-6 receptor (IL-6R) and the membrane-bound glycoprotein gp130. The complex I-6/IL-6R/gp130 starts the Janus kinases (JAKs) and signal transducer and activator of transcription 3 (STAT3) or JAK/STAT3 pathway. IL-6 R exits in two forms: a membrane-bound IL-6Rα subunit (mIL-6R) that participates in classic signalling pathway and soluble IL-6R subunit (sIL-6R) engaged in trans-signalling. The pro-tumour functions of IL-6 are associated with STAT3, a major oncogenic transcription factor that triggers up-regulation of target genes responsible for tumour cell survival. IL-6 combined with TGF-ß induces proliferation of pathogenic Th17 cells. The anti-tumour function of IL-6 is the promotion of anti-tumour immunity. IL-6 trans-signaling contributed to transmigration of lymphocytes in high endothelial venules (HEV). Dendritic cell (DC) secreted IL-6 in the lymph node influences the activation, distribution and polarisation of the immune response. Elevated serum levels of IL-6 and increased expression of IL-6 in tumour tissue are negative prognostic marker for patients' survival.

CD11c- and CD123-positive dendritic cells in development of antitumour immunity in non-small cell lung cancer patients.

Our aim was to analyzed the significance of CD11c and CD123 positive DCs and their relations with some clinical and pathologic parameters of patients with non-small cell lung cancer (NSCLC). The immunohistochemical expression of CD11c and CD123, was evaluated in 40 patients with NSCLC. After analysis we found that 35.3% of the patients in the T3-4 tumour stage had a high CD11c infiltration in the tumour stroma, while 100% of the patients in the T1-2 tumour stage had low infiltration (p = 0.03). We also found that 71.4% of patients in the M1 stage had a high infiltration with CD123 in the tumour stroma, whereas only 15.6% of patients without metastases had high infiltration, analogous data are also found in comparing the distribution of CD123 in the tumour border (p = 0.002 or p = 0.002). Comparing the density of CD123 in the border of lymph node involvement, we found that only 7.14% of patients without metastases had low infiltration with dendritic cells, whereas in patients with metastatic lymph nodes that percentage was 41.7% (p = 0.008). In conclusion results suggest that CD11c- and CD123-positive DCs play an important role in antitumour immunity and can be predictive factor for tumour development in patients with NSCLC.

The Position of Neutrophils-To-Lymphocytes and Lymphocytes-To-Platelets Ratio as Predictive Markers of Progression and Prognosis in Patients with Non-Small Cell Lung Cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) is an insidious metastasis condition of the lungs often presenting no symptoms at the onset. Defining markers for quick determination of prognosis is essential for building up a treatment strategy. AIM: The aim of this study is to define the role of the Neutrophils-to-Lymphocytes ratio (NLR) and Platelets-to- Lymphocytes ratio (PLR) as biomarkers in patients with NSCLC, according to the stage and prognosis of the disease. METHODS: We investigated 20 patients with NSCLC. NLR and PLR are calculated and are evaluated according to the presence or absence of metastasis, stage of the disease, histological type and survival rate. RESULTS: We found that thirteen of the patients had low NLR, while the rest 7 had high NLR (mean 3.15). By analysing PLR we found that 11 patients have low and 9 have high level of PLR (mean 1.42). After the correlations have been made we discovered that in 90.1% of the patients with low PLR no lymph metastasises were detected, while in 50% of the patients with high PLR lymph metastasises were observed (χ2 = 3.99; P = 0.046). We also discovered that in 84.6% of the patients with low NLR lymph metastases were absent, while in 42.9% with high NLR lymph metastasises were present (χ 2 = 1.83; P = 0.176). CONCLUSION: In conclusion, NLR and PLR were discovered as prominent biomarkers which provide relatively fast determination for prognosis in patients with NSCLC.

A Rare Case of Dermatofibrosarcoma Protuberans of the Thumb in an 80-year-old Woman.

Dermatofibrosarcoma protuberans (DFSP) has been described as a rare, locally invasive, malignant fibroblastic tumor with a high rate of recurrence that usually affects middle-aged patients. Herein, we describe a rare case of a pedunculated dermatofibrosarcoma protuberans of the right thumb in an 80-year-old woman treated with excision through the base of the pedicle. We also make a brief literature review concerning this tumor.

Association of IL-12Bpro polymorphism with tumor-infiltrating dendritic cells in colorectal cancer.

PURPOSE: Chronic inflammation is a key component in the development and progression of colorectal cancer (CRC). A notable hallmark of the inflammation process is the release of pro-inflammatory cytokines by infiltrating cells of the immune system. Defects in dendritic cells (DCs) recruitment, maturation and cytokine release are a hallmark of the CRC strategy to escape immune surveillance.The purpose of our study was to evaluate the possible role of IL-12B polymorphism in the promoter region of the IL-12B gene (rs17860508) as a genetic factor contributing to the risk for CRC development. Additionally, we aimed to evaluate the influence of this polymorphism on DCs infiltration in tumor microenvironment. METHODS: IL-12Bpro polymorphism was genotyped by Amplification Refractory Mutation System- Polymerase Chain Reaction (ARMS-PCR). Immunohistochemistry was performed for DCs infiltration. RESULTS: Statistically significant correlation between the expression of S100 and CD1a DCs and the 11- genotype of the studied polymorphism was found. No statistically significant difference in genotype distribution between cases and controls was observed (p=0.163). Analysis of the overall survival (OS) of genotyped patients revealed a tendency among the carriers of the 22-genotype to have shorter survival of 36 months versus the 11- and 12-cariers- 61 months (log rank, p=0.117). CONCLUSIONS: The IL-12Bpro polymorphism does not constitute a risk factor for CRC development. However, genotype-11 might have a complex role in the recruitment and maturation of DCs in tumor microenvironment.

Expression of E-Cadherin/Beta-Catenin in Epithelial Carcinomas of the Thyroid Gland.

BACKGROUND: The aberrant activation of Wnt signalling pathway may be a common denominator for the development of thyroid tumorigenesis. It was announced that the loss of E-cadherin rather than ß-catenin mutation represents a crucial event in determining the degree of differentiation of thyroid carcinomas. AIM: The aim of the study was to evaluate the expression of E-cadherin and ß-catenin in the thyroid cancer tissue and to correlate these data with some histological and clinical parameters of the tumours. MATERIAL AND METHODS: We investigated 112 patients, having thyroid tumours - papillary, follicular, anaplastic and oncocytic carcinomas immunohistochemically with antibodies against E-cadherin and ß-catenin. Survival analyses were done. RESULTS: E-cadherin expression was focally retained in the tumour cell membranes and the tumour cell cytoplasm of the papillary, follicular and oncocytic thyroid cancers, weather in anaplastic cancers it was almost lost (p = 0.0042, and p = 0.019, respectively, Fisher's Exact Test). The expression of ß-catenin in tumour cytoplasm and membrane in papillary cancers was higher as compared to that in the other tumours (p = 0.111, and p = 0.0104, respectively). CONCLUSION: Not surprisingly, the presence of aberrant expression of E-cadherin and ß-catenin in thyroid cancer has been associated with better patients' prognosis and better differentiated tumour histology.