Connective Tissue Development Research Articles

Effect of Silicon Supplementation in Diets with Different Calcium Levels on Bone Mineral Metabolism and Bone Status in Growing Female Rats

Abstract Objectives Silicon is important for the growth and development of bone and connective tissues. However, few studies have investigated effects of silicon supplementation on bone metabolism on growing females. We evaluated the effect of silicon supplementation on bone mineral metabolism and bone status in growing female rats fed diet with different calcium levels. Methods Sixty 6-wk-old Sprague-Dawley female rats were divided into 6 groups and fed diet with different levels of calcium (0.1%, 0.5%, 1.5%) and silicon (5 ppm, 500 ppm) for 10 weeks. We used a two-way ANOVA test to examine the difference and a significant level was set at P < 0.05. Results Silicon retention significantly increased by silicon supplementation and significantly decreased by high calcium diet (1.5%). Mg retention significantly decreased by high calcium diet. Serum calcium and silicon contents were not significantly different among the 6 groups. Low calcium diet (0.1% calcium) significantly increased serum osteocalcin and C-telopeptide cross-links of type I collagen (CTX) levels, and silicon supplementation significantly decreased CTX levels in the low calcium diet group. Bone mineral density was significantly increased along with greater calcium level in the diet, but was decreased by silicon supplementation in the high calcium diet. Rats in the 0.5% calcium diet group had significant increase in strength of the tibia by silicon supplementation. Conclusions According to our findings, the effect of silicon supplementation on bone metabolism may differ according to the calcium intake levels in growing females. Although further research is needed, when supplementing silicon to improve bone health in growing females, the calcium intake level should be considered. Funding Sources Korea Research Foundation.

Remodeling of aligned fibrous extracellular matrix by encapsulated cells under mechanical stretching

Extracellular matrix (ECM) remodeling is essential for the development and functions of connective tissues (e.g., heart, muscle and the periodontal ligament), and entails the highly anisotropic response of cells and their organized ECM molecules to mechanical stimulation. However, the nature of how cells remodel their surrounding ECM under mechanical stimulation remains elusive. Here, we encapsulated human periodontal ligament stem cells (hPDLSCs) within an aligned rat collagen scaffold labeled with fluorescein isothiocyanate (FITC) and applied mechanical stimulation on the scaffold using magnetic stretching. Through tracking the FITC-labeled rat collagen scaffold and the newly secreted human type I collagen, we studied the effect of magnetic stretching on the mechanism of aligned ECM remodeling by the encapsulated cells. We found that the aligned topography combined with magnetic stretching could significantly promote initial ECM degradation and new ECM secretion: expression of matrix metalloproteinases 1 and 9 is increased markedly, and the elastic modulus of the stretched scaffold (75 kPa) is significantly higher than that of the random scaffold (50 kPa). The data support a model whereby the cells remodel their surrounding ECM under continuous stretching through degradation and then secretion of new ECM to integrate with the aligned ECM and maintain tissue function. Our study offers a valuable basis for future optimized design of biomaterial scaffolds for clinical translation. Statement of significanceExtracellular matrix (ECM) remodeling is essential for the development and functions of connective tissues. However, the nature of how cells remodel their surrounding aligned ECM under mechanical stimulation remains elusive. Herein, we developed a method to reveal the remodeling of aligned rat collagen scaffold by the encapsulated human periodontal ligament stem cells (hPDLSCs) using fluorescence imaging. We found that the aligned topography combined with magnetic stretching could significantly promote initial ECM degradation and new ECM secretion: the expression of matrix metalloproteinase 1 and 9 are significantly higher, and the elastic modulus increases from 50 kPa to 75 kPa as compared to the random collagen scaffold encapsulating hPDLSCs. Our study holds great potential in optimization of bio-scaffold design for clinical translation.

Identification of co-expressed genes associated with MLL rearrangement in pediatric acute lymphoblastic leukemia.

Rearrangements involving the mixed lineage leukemia (MLL) gene are common adverse prognostic factors of pediatric acute lymphoblastic leukemia (ALL). Even allogeneic hematopoietic stem cell transplantation does not improve the outcome of ALL cases with some types of MLL rearrangements. The aim of the present study was to identify the co-expressed genes that related to MLL rearrangement (MLL-r) and elucidate the potential mechanisms of how MLL-r and their partner genes lead to leukemogenesis. Gene co-expression networks were constructed using the gene expression data and sample traits of 204 pretreated pediatric ALL patients, and co-expression modules significantly related to the MLL-r were screened out. Gene ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway analysis of the module genes were performed. Hub genes were identified and their expression levels were analyzed in samples with or without MLL-r and the results were validated by an independent investigation. Furthermore, the relationships between the hub genes and sample traits were analyzed. In total, 21 co-expression modules were identified. The green module was positively correlated with MLL-r. PROM1, LGALS1, CD44, FUT4 and HOXA10 were identified as hub genes, which were involved in focal adhesion, calcium-dependent phospholipid binding, connective tissue development and transcriptional misregulation in cancer. The expression levels of the five hub genes were significantly increased in MLL-r samples, and the results were further validated. PROM1, LGALS1, CD44 and HOXA10 were positively related to the leukocyte count. These findings might provide novel insight regarding the mechanisms and potential therapeutic targets for pediatric ALL with MLL-r.

Subsynovial connective tissue development in the rabbit carpal tunnel.

The carpal tunnel contains the digital flexor tendons and the median nerve, which are embedded in a unique network of fibrovascular interconnected subsynovial connective tissue (SSCT). Fibrous hypertrophy of the SSCT and subsequent adaptations in mechanical response are found in patients with carpal tunnel syndrome (CTS), but not much is known about the development of the SSCT. This observational study describes the morphological development of SSCT using histology and ultramicroscopy in an animal model at four time points between late‐term fetuses through adulthood. A transition is seen between 3 days and 6 weeks post‐partum from a dense solid SSCT matrix to a complex multilayered structure connected with collagenous fibrils. These preliminary data show a developmental pattern that matches an adaptive response of the SSCT to loading and motion. Understanding the anatomical development aids in recognizing the pathophysiology of CTS and supports research on new therapeutic approaches.

Effect of Silicon Supplementation in Diets with Different Calcium Levels on Balance of Calcium, Silicon and Magnesium, and Bone Status in Growing Female Rats.

Silicon (Si) is important for the growth and development of bone and connective tissues. This study aimed to evaluate the effect of Si supplementation on the balance of calcium (Ca), Si, magnesium (Mg), and bone status in growing female rats fed diets with different Ca levels. Sixty 6-week-old female Wistar rats were divided into 6 groups and fed diets with different levels of Ca (0.1, 0.5, 1.5%) and Si (5, 500ppm) for 10weeks. Experimental groups were as follows: Low-Ca group (LCa; 0.1% Ca), Low-Ca with Si supplementation group (LCaSi), adequate-Ca group (ACa; 0.5% Ca), adequate-Ca with Si supplementation group (ACaSi), high-Ca group (HCa; 1.5% Ca), and high-Ca with Si supplementation group (HCaSi). Si retention significantly increased by Si supplementation and significantly decreased by high-Ca diet (1.5%). Mg retention significantly decreased by high-Ca diet. Serum Ca and Si contents were not significantly different among the 6 groups. Low-Ca diet significantly increased serum osteoclain and C-telopeptide cross-link of type 1 collagen (CTx) levels, and Si supplementation significantly decreased CTx levels in the low-Ca diet group. Bone mineral density was significantly increased along with Ca increase in the diet, but was decreased by Si supplementation in the high-Ca diet. Rats in the adequate-Ca diet group had a significant increase in strength of tibia after Si supplementation. These findings indicate that the effect of Si supplementation on bone metabolism may differ according to the Ca-intake level in growing females. Although further research is needed, when supplementing Si to improve bone health in growing females, Ca-intake level should be considered.

Remodeling of Aligned Fibrous Extracellular Matrix by Encapsulated Cells Under Mechanical Stretching

Extracellular matrix remodeling is essential for the development and functions of connective tissues (e.g., heart, muscle and periodontal ligament), where ECM is generally with highly anisotropic features and under mechanical stimulation. However, the nature of how cells remodel their surrounding ECM under mechanical stimulation remains elusive. Herein, we encapsulated human periodontal ligament stem cells (hPDLSCs) within the aligned rat collagen scaffold labeled with fluorescein isothiocyanate (FITC) and provided continuous mechanical stimulation by magnetic stretching. Through tracking the FITC-labeled rat collagen scaffold and the newly secreted human type I collagen, we studied the mechanism of aligned ECM remodeling by encapsulated cells under mechanical stretching. We found that the aligned topography combined with magnetic stretching could significantly promote initial ECM degradation and new ECM secretion: the expression of matrix metalloproteinase 1 and 9 are significantly higher, and the elastic modulus increases from 50 kPa to 75 kPa as compared to the random collagen scaffold encapsulating hPDLSCs. Therefore, we decipher that cells remodel their surrounding ECM under continuous stretching through degradation and then secretion of new ECM to integrate with the aligned ECM and maintain tissue functions. Our study holds great potential in optimization of biomaterial scaffold design for clinical translation.

Mechanophysical Cues in Extracellular Matrix Regulation of Cell Behavior.

The extracellular matrix (ECM) is a macromolecular network that can provide biochemical and structural support for cell adhesion and formation. It regulates cell behavior by influencing biochemical and physical cues. It is a dynamic structure whose components are modified, degraded, or deposited during connective tissue development, giving tissues strength and structural integrity. The physical properties of the natural ECM environment control the design of naturally or synthetically derived biomaterials to guide cell function in tissue engineering. Tissue engineering is an important field that explores physical cues of the ECM to produce new viable tissue for medical applications, such as in organ transplant and organ recovery. Understanding how the ECM exerts physical effects on cell behavior, when cells are seeded in synthetic ECM scaffolds, is of utmost importance. Herein we review recent findings in this area that report on cell behaviors in a variety of ECMs with different physical properties, i.e., topology, geometry, dimensionality, stiffness, and tension.

Structural and Functional Changes in the Mesenteric Lymph Nodes in Humans during Aging

Morphometric analysis of structural and functional changes in the human mesenteric lymph nodes during aging revealed the development of fibrous connective tissue, fragmentation of the lymphoid parenchyma, the absence of follicles with germinal centers, and a decrease in the level of lymphocyte proliferation, which was confirmed by the absence of Ki-67+ cells. The paracortical zone lacked CD4+ T helpers that regulate both cellular and humoral immunity. High content of plasma cells and eosinophilic granulocytes in the medullary cords and sinuses reflects the development of autoimmune processes associated with a decrease in the number of regulatory T lymphocytes. The development of fibrous connective tissue in the sinus system complicates lymph flow through the lymph node and impairs lymph filtration.

PATHOMORPHOLOGICAL CHANGES IN STRUCTURE OF INTRAHEPATIC DUCTS AND CHOLEDOCH IN PATIENTS WITH ACUTE AND CHRONIC CHOLANGITIS

Summary. Aim. To determine the morphological state of bile duct wall cells in patients with acute and chronic cholangitis at different times after removal of bile hypertension.
 Materials and methods. During laparotomy surgery, a bile duct wall biopsy was performed in 48 patients with cholangitis, conditionally divided into 4 groups depending on the period of removal of biliary hypertension: up to 5 days, 12-14 days, 28-30 days and 10-12 months. The control group included 12 patients with choledocholithiasis without clinical signs of cholangitis.
 Results and its discussion. Acute cholestasis was recorded in the intrahepatic bile ducts, the expression of which occurred in the first 2 weeks. In the period of 28-30 days, residual effects of acute cholangitis and proliferation of connective tissue both in the walls of the ducts and around them were recorded. In the bile duct wall of patients with cholangitis, the largest changes were recorded within 3-5 days from the beginning of decompression in the form of edematous-desquamative and necrotic phenomena on the part of the epithelium. On the 12-14th day, “attenuation” and demarcation of the inflammatory process were noted, and on the 28-30th day – the development of connective tissue. In patients with long-term (6-12 months) chronic cholangitis, the phenomena of cholestasis, cholangiosclerosis and biliary cirrhosis of the liver were documented, which were not subjected to regression.
 Conclusions. The most pleasant for reconstructive interventions after the elimination of cholangitis and biliary hypertension is a period of 3-6 weeks. With prolonged cholangitis, the phenomena of sclerosis and cirrhosis are not regressed.

Quantitative Determination of Vitamin C Concentration of Common Edible Food Sources by Redox Titration Using Iodine Solution

Vitamin C is isolated in 1928 and associated with hemorrhagic disease scurvy. Vitamin C is crucial for the development and maintenance of connective tissues in humans. It plays an important role in maintaining healthy gums, helps in wound healing, bone formation, relief from a common cold, and several metabolic functions. It is an antioxidant that safeguards the cells from free radical damage. It is used as a curative agent in many diseases and disorders. This research article attempts to find different concentrations of vitamin C in common edible foodstuffs. The iodine redox titration method is used for vitamin C quantity evaluation. This study is based on the vitamin C quantity of 27 common edible food sources, including lemon (Citrus limon), lime (Citrus aurantiifolia), navel orange (Citrus sinensis), grapevine (Vitis vinifera), fox grape (Vitis labrusca), pomegranate (Punica granatum), apple (Malus domestica), kiwifruit (Actinidia deliciosa), Indian tamarind (Tamarindus indica), holy basil (Ocimum tenuiflorum), coriander (Coriandrum sativum), tomato (Solanum lycopersicum), carrot (Daucus carota), radish (Raphanus sativus), bitter gourd (Momordica charantia), garlic (Allium sativum), onion (Allium cepa), potato (Solanum tuberosum), aubergine (Solanum melongena), bell pepper (Capsicum annuum), pea (Pisum sativum), common bean (Phaseolus vulgaris), pumpkin (Cucurbita moschata), pawpaw (Carica papaya), cucumber (Cucumis sativus), cabbage (Brassica oleracea var. capitata), and cauliflower (Brassica oleracea var. botrytis), are evaluated. The highest quantity of vitamin C present in Indian tamarind, i.e., 89.44 mg/100 g. This study is intended to use new vitamin C sources for nourishment.

Способ профилактики воспалительных процессов костного отдела наружного слухового прохода, сопровождающихся ростом соединительной ткани

Otosurgery plays an important role in the rehabilitation of patients with hearing loss. Any operation can be accompanied by a long inflammatory process with excessive development of connective tissue, forming atresia or stenosis of the external auditory canal. Formed scars in the external auditory canal reduce the effectiveness of treatment and can lead to reoperation. In the treatment of scars, the use of injections of a suspension of prolonged steroids directly into the developing connective tissue is effective. We have developed a method of injecting drugs into the scar tissue of the bone section of the external auditory canal, which allows the use of such therapy in patients after otosurgery. 12 people were treated with the proposed technique. All patients had an inflammatory process in the external auditory canal with undesirable growth of connective tissue. Previous local therapy did not bring a satisfactory result. Patients received injections of a suspension of steroids into developing scar tissue. The treatment period was 1-8 weeks, for which 1 to 4 sessions of injections were performed. As a result of treatment according to the developed method, in all cases a cessation of the pathological inflammatory process was observed. Timely therapy made it possible to completely eliminate the excess granulation tissue (100%), to stop the growth of the scar, or even to cause a significant decrease (33%). The developed method allows to use of a small dose of a substance (0,1–0,5 ml) for injection to achieve the desired therapeutic effect.

Recent Advances in the Pathophysiology of Musculocontractural Ehlers-Danlos Syndrome.

Musculocontractural Ehlers–Danlos Syndome (mcEDS) is a type of EDS caused by biallelic pathogenic variants in the gene for carbohydrate sulfotransferase 14/dermatan 4-O-sulfotransferase 1 (CHST14/D4ST1, mcEDS-CHST14), or in the gene for dermatan sulfate epimerase (DSE, mcEDS-DSE). Thus far, 41 patients from 28 families with mcEDS-CHST14 and five patients from four families with mcEDS-DSE have been described in the literature. Clinical features comprise multisystem congenital malformations and progressive connective tissue fragility-related manifestations. This review outlines recent advances in understanding the pathophysiology of mcEDS. Pathogenic variants in CHST14 or DSE lead to reduced activities of relevant enzymes, resulting in a negligible amount of dermatan sulfate (DS) and an excessive amount of chondroitin sulfate. Connective tissue fragility is presumably attributable to a compositional change in the glycosaminoglycan chains of decorin, a major DS-proteoglycan in the skin that contributes to collagen fibril assembly. Collagen fibrils in affected skin are dispersed in the papillary to reticular dermis, whereas those in normal skin are regularly and tightly assembled. Glycosaminoglycan chains are linear in affected skin, stretching from the outer surface of collagen fibrils to adjacent fibrils; glycosaminoglycan chains are curved in normal skin, maintaining close contact with attached collagen fibrils. Homozygous (Chst14−/−) mice have been shown perinatal lethality, shorter fetal length and vessel-related placental abnormalities. Milder phenotypes in mcEDS-DSE might be related to a smaller fraction of decorin DS, potentially through residual DSE activity or compensation by DSE2 activity. These findings suggest critical roles of DS and DS-proteoglycans in the multisystem development and maintenance of connective tissues, and provide fundamental evidence to support future etiology-based therapies.

Transcriptome profiling of posterior kidney of brown trout, Salmo trutta, during proliferative kidney disease

BackgroundTetracapsuloides bryosalmonae is a myxozoan parasite which causes economically important and emerging proliferative kidney disease (PKD) in salmonids. Brown trout, Salmo trutta is a native fish species of Europe, which acts as asymptomatic carriers for T. bryosalmonae. There is only limited information on the molecular mechanism involved in the kidney of brown trout during T. bryosalmonae development. We employed RNA sequencing (RNA-seq) to investigate the global transcriptome changes in the posterior kidney of brown trout during T. bryosalmonae development.MethodsBrown trout were exposed to the spores of T. bryosalmonae and posterior kidneys were collected from both exposed and unexposed control fish. cDNA libraries were prepared from the posterior kidney and sequenced. Bioinformatics analysis was performed using standard pipeline of quality control, reference mapping, differential expression analysis, gene ontology, and pathway analysis. Quantitative real time PCR was performed to validate the transcriptional regulation of differentially expressed genes, and their correlation with RNA-seq data was statistically analyzed.ResultsTranscriptome analysis identified 1169 differentially expressed genes in the posterior kidney of brown trout, out of which 864 genes (74%) were upregulated and 305 genes (26%) were downregulated. The upregulated genes were associated with the regulation of immune system process, vesicle-mediated transport, leucocyte activation, and transport, whereas the downregulated genes were associated with endopeptidase regulatory activity, phosphatidylcholine biosynthetic process, connective tissue development, and collagen catabolic process.ConclusionTo our knowledge, this is the first RNA-seq based transcriptome study performed in the posterior kidney of brown trout during active T. bryosalmonae development. Most of the upregulated genes were associated with the immune system process, whereas the downregulated genes were associated with other metabolic functions. The findings of this study provide insights on the immune responses mounted by the brown trout on the developing parasite, and the host molecular machineries modulated by the parasite for its successful multiplication and release.

Genomic Divergence in Swedish Warmblood Horses Selected for Equestrian Disciplines.

The equestrian sport horse Swedish Warmblood (SWB) originates from versatile cavalry horses. Most modern SWB breeders have specialized their breeding either towards show jumping or dressage disciplines. The aim of this study was to explore the genomic structure of SWB horses to evaluate the presence of genomic subpopulations, and to search for signatures of selection in subgroups of SWB with high or low breeding values (EBVs) for show jumping. We analyzed high density genotype information from 380 SWB horses born in the period 2010–2011, and used Principal Coordinates Analysis and Discriminant Analysis of Principal Components to detect population stratification. Fixation index and Cross Population Extended Haplotype Homozygosity scores were used to scan the genome for potential signatures of selection. In accordance with current breeding practice, this study highlights the development of two separate breed subpopulations with putative signatures of selection in eleven chromosomes. These regions involve genes with known function in, e.g., mentality, endogenous reward system, development of connective tissues and muscles, motor control, body growth and development. This study shows genetic divergence, due to specialization towards different disciplines in SWB horses. This latter evidence can be of interest for SWB and other horse studbooks encountering specialized breeding.

Hedgehog Signaling Inhibition by Smoothened Antagonist BMS-833923 Reduces Osteoblast Differentiation and Ectopic Bone Formation of Human Skeletal (Mesenchymal) Stem Cells.

Background Hedgehog (Hh) signaling is essential for osteoblast differentiation of mesenchymal progenitors during endochondral bone formation. However, the critical role of Hh signaling during adult bone remodeling remains to be elucidated. Methods A Smoothened (SMO) antagonist/Hedgehog inhibitor, BMS-833923, identified during a functional screening of a stem cell signaling small molecule library, was investigated for its effects on the osteoblast differentiation of human skeletal (mesenchymal) stem cells (hMSC). Alkaline phosphatase (ALP) activity and Alizarin red staining were employed as markers for osteoblast differentiation and in vitro mineralization capacity, respectively. Global gene expression profiling was performed using the Agilent® microarray platform. Effects on in vivo ectopic bone formation were assessed by implanting hMSC mixed with hydroxyapatite-tricalcium phosphate granules subcutaneously in 8-week-old female nude mice, and the amount of bone formed was assessed using quantitative histology. Results BMS-833923, a SMO antagonist/Hedgehog inhibitor, exhibited significant inhibitory effects on osteoblast differentiation of hMSCs reflected by decreased ALP activity, in vitro mineralization, and downregulation of osteoblast-related gene expression. Similarly, we observed decreased in vivo ectopic bone formation. Global gene expression profiling of BMS-833923-treated compared to vehicle-treated control cells, identified 348 upregulated and 540 downregulated genes with significant effects on multiple signaling pathways, including GPCR, endochondral ossification, RANK-RANKL, insulin, TNF alpha, IL6, and inflammatory response. Further bioinformatic analysis employing Ingenuity Pathway Analysis revealed significant enrichment in BMS-833923-treated cells for a number of functional categories and networks involved in connective and skeletal tissue development and disorders, e.g., NFκB and STAT signaling. Conclusions We identified SMO/Hedgehog antagonist (BMS-833923) as a powerful inhibitor of osteoblastic differentiation of hMSC that may be useful as a therapeutic option for treating conditions associated with high heterotopic bone formation and mineralization.

I.6Arthrogryposis multiplex congenita; new genes & old acquaintances

Arthrogryposis multiplex congenita (AMC) is a multi-facetted disease that is characterized by congenital contractures in two or more body regions, which might or might not be accompanied by additional symptoms, being termed "syndromic" or "isolated" arthrogryposis. The disease is further clinically divided into "proximal" and "distal" arthrogryposis, depending on whether large or smaller distal joints of hands and feet are predominantly affected. AMC results from an overall lack of fetal movement (fetal akinesia), which in turn might have a multitude of etiologies with presently more than 120 having a genetic underpinning. Genetic defects mainly revolve around the development and maintenance of the motor unit and the reflex arch. Mutations may affect proteins with a role in the development of connective and contractile muscle tissue, in the biogenesis of the neuromuscular endplate, and in neuronal myelination. Other proteins may be involved in neuronal pathfinding, signaling, and cellular transport mechanisms or participate in the local or central control of muscle tension. This lecture will give an overview over the multiple etiologies and will try a classification on genetic and clinical grounds, which could support the diagnosing physicians to find the correct diagnosis in their patients. Finally, we will present a novel genetic defect that causes spontaneously regressing AMC associated with dilated cardiomyopathy.

Morphological changes in the walls of varicose veins of the lower extremities during minimally invasive surgical treatment

The vein wall was investigated in the treatment of patients with varicose veins by endovenous laser and radiofrequency ablation. Fragments of removed veins with varicose veins served as material for pathomorphological research. The following histological staining methods were used: hematoxylin and eosin, van Gieson’s picrofuchsin with additional staining on elastica, according to Mallory. It has been shown, that with varicose veins of the lower extremities, pronounced irreversible morphological changes develop in the vein wall in the form of damage to endothelial cells, hypertrophy of all layers of the vein wall, total development of connective tissue in it with impaired collagen structure both in the basement membrane of endothelial cells and in muscle and elastic layers. Changes in the structure of collagen in the vein wall can be traced in all studied groups, which seems possible, since the treatment with minimally invasive methods is carried out against the background of already altered venous trunks. At the same time, injuries in the vein wall are most pronounced when using endovenous laser coagulation of veins and are accompanied by frequent pain in the postoperative period. The latter is confirmed by morphological changes in the form of total necrosis of the vein wall with necrosis and complete desquamation of the endothelium into the lumen of the vessel. Damage to the wall of the vein of the lower extremities, altered by a chronic current process with varicose veins, including its endothelium and all layers, is minimized when using radiofrequency ablation. Accordingly, cicatrization of surrounding fabrics in the zone of action of radiofrequency ablation will pass in more short spaces and with a favourable end for a patient, that it is confirmed by the less number of paresthesias and sickliness on motion a vein in a postoperative period.

Proteomic Analysis of Morphologically Changed Tissues after Prolonged Dexamethasone Treatment.

Prolonged dexamethasone (Dex) administration leads to serious adverse and decrease brain and heart size, muscular atrophy, hemorrhagic liver, and presence of kidney cysts. Herein, we used an untargeted proteomic approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous identification of changes in proteomes of the major organs in Sprague–Dawley (SD rats post Dex treatment. The comparative and quantitative proteomic analysis of the brain, heart, muscle, liver, and kidney tissues revealed differential expression of proteins (n = 190, 193, 39, 230, and 53, respectively) between Dex-treated and control rats. Functional network analysis using ingenuity pathway analysis (IPA revealed significant differences in regulation of metabolic pathways within the morphologically changed organs that related to: (i) brain—cell morphology, nervous system development, and function and neurological disease; (ii) heart—cellular development, cellular function and maintenance, connective tissue development and function; (iii) skeletal muscle—nucleic acid metabolism, and small molecule biochemical pathways; (iv) liver—lipid metabolism, small molecular biochemistry, and nucleic acid metabolism; and (v) kidney—drug metabolism, organism injury and abnormalities, and renal damage. Our study provides a comprehensive description of the organ-specific proteomic profilesand differentially altered biochemical pathways, after prolonged Dex treatement to understand the molecular basis for development of side effects.

Cross-cultural adaptation of the connective tissue disease screening questionnaire and development of a Chinese version in a multi-ethnic Asian population.

To cross-culturally adapt the Connective Tissue Disease (CTD) Screening Questionnaire (CSQ) in a multi-ethnic Asian population in Singapore. An expert panel of accredited rheumatologists evaluated the content validity of the original CSQ. Consenting participants newly referred from primary care to a rheumatology specialist outpatient clinic for evaluation of possible CTDs were studied. Cognitive debriefing interviews (CDIs) using the original CSQ were conducted with English-speaking participants, with modifications made based on their inputs and in discussion with a second expert panel (rheumatologists and the CSQ developers). Forward and back translations of the adapted English version were reviewed by the second expert panel. The common translation produced was tested in CDIs with Chinese-speaking participants. Adapted English and Chinese versions were pilot tested in a separate group of newly referred patients. Content validity of the original CSQ was confirmed by the expert panel. A total of 30 and 15 participants were recruited for English and Chinese CDIs, respectively. Alternative terms and explanatory notes were added to difficult medical terms in the adapted English CSQ. A further explanatory note was added to one difficult item, and English medical terms were retained in the Chinese version. Pilot testing of the adapted CSQ was performed on 116 participants, which exhibited an overall sensitivity and specificity of 71% and 58%, respectively, in identifying CTDs. The adapted CSQ demonstrated satisfactory sensitivity in the pilot testing and appears to be a promising tool for facilitating early identification of CTDs in the multi-ethnic Asian population. • Early identification and management of patients with CTDs is crucial given their high disease burden and short "windows of opportunity." • High reliability and validity of original CSQ and its cross-culturally adapted versions have been reported; however, the CSQ has not been validated in Southeast Asia where CTDs are associated with higher morbidity and mortality compared to other countries. • Our cross-culturally adapted CSQ demonstrated satisfactory sensitivity in identifying CTDs in the multi-ethnic Asian population.

GROWTH AND DEVELOPMENT SYMPOSIUM: STEM AND PROGENITOR CELLS IN ANIMAL GROWTH: The regulation of beef quality by resident progenitor cells1.

The intramuscular adipose tissue deposition in the skeletal muscle of beef cattle is a highly desired trait essential for high-quality beef. In contrast, the excessive accumulation of crosslinked collagen in intramuscular connective tissue contributes to beef toughness. Recent studies revealed that adipose tissue and connective tissue share an embryonic origin in mice and may be derived from a common immediate bipotent precursor in mice and humans. Having the same linkages in the development of adipose tissue and connective tissue in beef, the lineage commitment and differentiation of progenitor cells giving rise to these tissues may directly affect beef quality. It has been shown that these processes are regulated by some key transcription regulators and are subjective to epigenetic modifications such as DNA methylation, histone modifications, and microRNAs. Continued exploration of relevant regulatory pathways is very important for the identification of mechanisms influencing meat quality and the development of proper management strategies for beef quality improvement.