Structural Investigation of Epididymal Microvasculature and Its Relation to Telocytes and Immune Cells in Camel.

The vascular and perivascular cells, including telocytes (TCs) and immune cells, play an important role in male fertility. The current study intended to describe in detail the microvascular structures harboring special regulatory devices in addition to the interstitial cellular components of the one-humped camel epididymis. The samples were collected from 10 clinically healthy mature camels (Camelus dromedarius). The distribution and characteristics of TCs, peripheral blood vessels of the epididymis, and immune cells were investigated using the light, immunohistochemistry, immunofluorescence, and transmission electron microscopy analyses. Frequent occlusive or throttle arterioles were demonstrated in the epididymal interstitium and their tunica media consisted of glomus cells. In addition, some vein walls consisted of one or two layers of glomus cells. TCs, fibroblasts, muscle cells, and tunica media of the blood vessels, that present in the loose connective tissue surrounding the intertubular interstitium of camel epididymis, showed a positive reaction with vimentin. The endothelium of blood vessels and veins showed positive immunoreactivity for CD34 and vascular endothelial growth factor (VEGF). Furthermore, VEGF, CD34, and S100 proteins were expressed in dendritic cells (DCs) as well as TCs. The current data suggest the involvement of DCs and TCs in angiogenesis and a possible role for the interstitial components in creating an appropriate milieu for the full maturation of sperms.

Changes in the Structure and Cell Composition of Human Carinal Lymph Nodes during Aging.

Changes in the structure and cell composition of carinal lymph nodes were studied in humans during aging. Replacement of node parenchyma with fibrous connective tissue progressing with age was demonstrated. The medullary matter significantly prevailed over the cortical substance. The lymph nodes in the cortical substance were small and had no light centers; the concentration of mature CD20+ B cells was high; the paracortical area was fragmented and thinned and contained no CD4+ T helpers. Ki-67+ cells were absent in all structural components of the lymph nodes reflecting exhaustion of lymphopoietic function, which was determined by the replacement of the reticular tissue of the microenvironment with the connective tissue and by the absence of CD4+ T cells regulating cellular and humoral immunity. The disintegration of the reticular stroma in the sinus system that acts as a biological filter impairs the function of lymph purification.

A single stranded fluorescent peptide probe for targeting collagen in connective tissues.

We herein report the construction of a novel single stranded fluorescent collagen mimetic peptide by introducing a bulky FAM dye in the central region rather than the N terminus. Without the need for any prior thermal or ultraviolet treatment, the peptide probe can be conveniently applied to specifically target collagen in connective tissues for fluorescence imaging.

New insights into the cellular makeup and progenitor potential of palatal connective tissues.

The present study investigated the regenerative potential of connective tissues harvested from two palatal areas widely used as donor sites for muco-gingival surgical approaches. Connective tissue grafts (CTGs) were obtained by de-epithelialisation of a free gingival graft (deCTG) and by a split flap approach from a previous donor site (reCTG). Two types of mesenchymal stem cell (MSCs) were isolated and were named de-epithelialised MSCs (deMSCs) and re-entry MSCs (reMSCs). The cells were characterised and cellular functionality was investigated. CTGs were evaluated using immunohistochemical and ultrastructural approaches. No significant differences were observed regarding the frequency of colony-forming unit- fibroblasts, migration potential, and population doubling time between the two cell lines (p > 0.05). Both cell lines showed positivity for CD105, CD73, CD90, and CD44 and negative expression for CD34/45, CD14, CD79a, and HLA-DR. MSCs from both cell lines successfully differentiated into osteogenic, adipogenic, and chondrogenic lineages. Cells expressing antigens characteristic of CD34+ stromal cells (CD34+, αSMA-, CD31-) were traced in both CTGs. Ultrastructural analysis highlighted the presence of putative progenitors, namely fibroblasts,-in the pericapillary regions and in remote regions of the lamina propria- and pericytes-surrounding the capillaries. This study provides supplementary arguments for the use of CTG grafts in clinical practice due to the presence of putative progenitor cell. However, results were inconclusive regarding clinical decision-making to determine optimal harvesting area. Prior harvesting in the donor area did not appear to alter the regenerative capabilities of the connective tissue.

Arrangement of Peri-implant Connective Tissue Fibers Around Platform-Switching Implants with Conical Abutments and Its Relationship to the Underlying Bone: A Human Histologic Study.

The objective of this study was to clarify and evaluate the orientation of the collagen fibers around platform-switching (PS) implants with conical abutments in humans after 8 weeks of healing, and to determine how this orientation would help stabilize the soft tissue and prevent bone resorption. On PS implants, circular orientation of collagen fiber was observed as the main arrangement in a cross-sectional view. The circular collagen fibers might be the key factor in stabilizing the soft tissues around the rehabilitation, inhibiting apical migration of the soft tissues and, in turn, protecting the underlying bone.

Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

OBJECTIVE: To describe the ultrastructural features of hereditary gingival fibromatosis (HGF) in affected family members and compare microscopic findings with normal gingival (NG) tissue. STUDY DESIGN: Gingival tissue samples from nine patients with HGF from five unrelated families were evaluated by transmission electron microscopy. Nine NG tissue samples were used for comparison. RESULTS: Areas containing collagen fibrils forming loops and folds were observed in both groups, whereas oxytalan fibers were frequently identified in the HGF group. The diameter of collagen fibrils and the interfibrillar space among them were more uniform in the NG group than in the HGF group. Fibroblasts were the most common cells found in both the HGF and NG groups and exhibited enlarged, rough endoplasmic reticulum, mitochondria with well-preserved crests, conspicuous nucleoli, and euchromatic chromatin. Other cells, such as mast cells, plasma cells, and macrophages, were also observed. CONCLUSIONS: HGF tissues had ultrastructural characteristics that were very similar to those of NG tissues. Oxytalan fibers were observed more frequently in the HGF samples than in the NG samples. Other studies of HGF in patients from different families should be performed to better understand the pathogenesis of this hereditary condition.

A rat model of radiation injury in the mandibular area.

BACKGROUND: Radiation technology focuses on delivering the radiation as precisely as possible to the tumor, nonetheless both acute and long-term damage to surrounding normal tissue may develop. Injuries to the surrounding normal tissue after radiotherapy of head and neck cancer are difficult to manage. An animal model is needed to elucidate good treatment modalities. The aim of this study was to establish a rat model where a certain radiation dose gives reproducible tissue reactions in the mandibular area corresponding to injuries obtained in humans. METHOD: The left mandible of male Sprague Dawley rats was irradiated by external radiotherapy (single fraction 15 Gy, total dose 75 Gy) every second week five times. Endpoint was six weeks after last radiation treatment, and the test group was compared to non-irradiated controls. Morphological alterations of the soft tissues, bone and tooth formation, as well as alterations of salivation, vascularity and collagen content were assessed. An unpaired, non-parametric Mann-Whitney test was used to compare the statistical differences between the groups. RESULTS: Analysis of the soft tissues and mandible within the radiation field revealed severe unilateral alopecia and dermatitis of the skin, extensive inflammation of the submandibular gland with loss of serous secretory cells, hyperkeratinization and dense connective fiber bundles of the gingival tissue, and disturbed tooth development with necrosis of the pulp. Production of saliva and the vascularity of the soft tissues were significantly reduced. Furthermore, the collagen fibril diameter was larger and the collagen network denser compared to non-irradiated control rats. CONCLUSION: We have established an animal model of radiation injury demonstrating physiological and histological changes corresponding to human radiation injuries, which can be used for future therapeutic evaluations.

Chievitz' juxtaparotid organ, free from cancer.

INTRODUCTION: Up to the half of twentieth century, Chievitz organ was considered an embryonal organ, disappearing with growth. But Zenker, in 1953, demonstrated the existence of this organ in adult life, too4. REVIEW: In this article we review the embryology, the macroscopic and microscopic anatomy, the ultrastructure, the functional significance and the pathology of the Chievitz'Juxtaparotid Organ (CJO). The CJO is not a macroscopic apparent organ, but it looks like a nerve. The CJO takes connections with buccinator muscle, at the level of the parotid duct, and the medial pterygoid muscle. The cell parenchyma is enveloped by the connective tissue, that is divided into three layers15, 16: the inner layer -"stratum fibrosum internum"-, composed of collagenous and elastic microfibrils; the middle layer - "stratum nervosum" - containing a lamellar inner core and Ruffini SNF5; the external layer - "stratum fibrosum externum", that is a collagen capsule. The parenchymal cells show a rich enzyme activity. The parenchymal cells may play the same role as glomus cells of the 1st type and Merkel cells20, 21. When a surgical resection is performed for an oral carcinoma, the CJO may be present in the specimen25. The CJO may be wrongly diagnosed as perineural invasion by carcinoma26, 27, 28. CONCLUSION: We report that Chievitz' organ is the only organ in which the cancer does not occur. KEY WORDS: Chievitz' organ, Juxtaoral organ, Parotid gland.

Reinvestigation of epithelial lining of the genital coelomic sinus in asteroids. An ultrastructural study.

Ultrastructural study of gonadal muscles in sea star, Asterina pectinifera, showed that myoepithelial cells were located only in the epithelial lining of the genital coelomic sinus. No myoepithelial cells were found in the visceral peritoneal epithelium or within connective tissue layer of the outer sac. Morphology of the myoepithelial cells in gonads of A. pectinifera varies during the reproductive cycle. During the gametogenic phase of the reproductive cycle, the myoepithelial cells get an elongated, spindle-like shape having a length of 20­30 m. In prespawning gonads, many of the myoepithelial cells form cytoplasmic extensions of 3­5 m in length, filled with myofilaments and penetrating into the underlying connective tissue of the outer sac or haemal sinus. Besides, myoepithelial cells, simultaneously anchored in the inner and outer sacs, were also observed. These changes result in development of more elaborated musculature and increase in contractility of the gonadal wall in prespawning gonads as compared to that during other stages of the reproductive cycle.

Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766).

The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae.

Topographic distribution of the different cell types, connective tissue and vascular tissue/lumina within a functional bovine corpus luteum and its association with breed, type of fixation protocol and stage during the cycle.

In the present study, we analysed the effect of fixative, breed, luteal stage and location on the nuclear density, volume density of connective tissue and vascular tissue/lumina within a bovine luteal gland in view of the development of an in vivo sampling technique to longitudinally monitor luteal histophysiology. The inner zone defined as the zone geometrically closest to the centre of the gland shows a significantly lower nuclear density (for all cell types) and a higher volume density of collagen fibres and vessels when compared with the outer zone (p < 0.001). The nuclear density in luteal glands from Holstein-Friesian cows is not significantly different from that in Belgian Blue cows, nor is it in stage II vs stage III glands. The collagen fibre content was significantly lower in glands of Belgian Blue cows (p = 0.01) and in younger glands (p = 0.003). Hence, it seems that the lower nuclear density in the inner zone was compensated by a higher amount of collagen fibres. As the type of fixative applied has a significant effect on the nuclear density of the different cell types, the present study warrants future research to further optimize the fixation protocol. As a conclusion, we can state that the topographic difference in nuclear distribution for the different cell types in a bovine luteal gland is only significant when comparing the inner vs the outer zone. This implies that if a sample representative for the whole gland has to be taken, for example, when taking an in vivo sample, it is necessary that the biopsy goes through the inner zone and contains the total diameter of the gland.

The ultrastructure of the fascia lata in hernia patients and healthy controls.

BACKGROUND: Current research data indicate that a hernia is a manifestation of a generalized polyethiological connective tissue pathology. The goal of this study was to demonstrate ultrastructural differences in tissues distant from the hernial defect. MATERIALS AND METHODS: Biopsy specimens harvested upon thigh surgery from 12 males aged 25-65 y were compared. Seven of these men had an inguinal hernia or a history thereof. Scanning electron microphotograms taken at a magnification of 50× were analyzed with the use of Image J software. For every patient, 100 thickness measurements were performed of the fibrous elements (cross-sections) visible in five consecutive photograms. The person performing the measurements had no means of identifying the patient from whom the specimen had been harvested. RESULTS: The authors have found the thickness of the fibers to fall in the range from 23.441 u (ImageJ intrinsic units) to 94.878 u in the hernia group and 22.067 u to 303.681 u for the control group. A statistically significant difference was found between the mean values of thickness measurements of the fibrous elements in the study and control groups. CONCLUSIONS: The study has shown that in patients with an inguinal hernia, the mean diameter of fibers within the fascia lata is significantly smaller. This appears to indicate that the process is generalized and that one can expect the structural alterations to occur within the connective tissue of the entire organism. The authors speculate that they may result from a combination of external and internal factors.

Structural characteristics of septal cartilage and mucoperichondrium.

AIM: During nasal septum surgery, elevation of mucoperichondrium from the anterior nasal septum may be more difficult than from the medial and posterior septum. This study aimed to evaluate any histological structural differences between the anterior and posterior nasal septum cartilage, mucoperichondrium and intervening tissue. MATERIAL AND METHOD: Unilateral mucoperichondrial flap elevation without infiltration was performed, after nasal tip and dorsum decortication, in four patients undergoing open septorhinoplasty. Full-thickness samples, including cartilage and mucoperichondrium, were removed from the anterior and posterior nasal septum and examined under light and electron microscopy. RESULTS: Light microscopy showed no difference between anterior and posterior septum specimens regarding perichondrial thickness and subperichondrial cell density. Demarcation between cartilage and perichondrium and between perichondrium and lamina propria was more regular in the posterior versus the anterior septum. Electron microscopy showed no difference in chondroblast activity at the two sites. CONCLUSION: The observed tissue demarcation irregularities may explain the greater reported difficulty in elevating anterior versus posterior nasal septum mucoperichondrium. Immunohistochemical examination would further elucidate these interstructural connections.

[Paravasal connective tissue of the in-wall blood vessels of the heart during aging].

The structural organization of the paravasal connective tissue of the in-wall myocardial blood vessels in the stages of postnatal ontogenesis was studied. The study was carried out on preparations of the heart 80 corpses of men in three age groups (the first period of adulthood (n = 20) and elderly (n = 30) and old (n = 30) ages.) The peculiarities of the structure as well as qualitative and quantitative transformation of fibrous component of the paravasal connective tissue in each age period were revealed.

Ahnak1 abnormally localizes in muscular dystrophies and contributes to muscle vesicle release.

Ahnak1 is a giant, ubiquitously expressed, plasma membrane support protein whose function in skeletal muscle is largely unknown. Therefore, we investigated whether ahnak would be influenced by alterations of the sarcolemma exemplified by dysferlin mutations known to render the sarcolemma vulnerable or by mutations in calpain3, a protease known to cleave ahnak. Human muscle biopsy specimens obtained from patients with limb girdle muscular dystrophy (LGMD) caused by mutations in dysferlin (LGMD2B) and calpain3 (LGMD2A) were investigated for ahnak expression and localization. We found that ahnak1 has lost its sarcolemmal localization in LGMD2B but not in LGMD2A. Instead ahnak1 appeared in muscle connective tissue surrounding the extracellular site of the muscle fiber in both muscular dystrophies. The entire giant ahnak1 molecule was present outside the muscle fiber and did only partially colocalize with CD45-positive immune cell infiltration and the extracelluar matrix proteins fibronectin and collagenVI. Further, vesicles shedded in response to Ca(2+) by primary human myotubes were purified and their protein content was analysed. Ahnak1 was prominently present in these vesicles. Electron microscopy revealed a homogenous population of vesicles with a diameter of about 150 nm. This is the first study demonstrating vesicle release from human myotubes that may be one mechanism underlying abnormally localized ahnak1. Taken together, our results define ahnak1 in muscle connective tissue as a novel feature of two genetically distinct muscular dystrophies that might contribute to disease pathology.

Ultrastructural differences in rectus sheath of hernia patients and healthy controls.

BACKGROUND: The etiology of inguinal hernia remains unclear. Research data indicate the presence of pathologic alterations within the connective tissue; their exact character remains the subject of dispute. The search for new methods to diagnose connective tissue abnormalities, and thoroughly explain the character of the ultrastructural alterations, continues. MATERIALS AND METHODS: The study group included 10 male patients aged 18-60 y (five with primary inguinal hernia and five with acute appendicitis with no history of hernia). A specimen of the rectus muscle sheath was harvested from all of them upon surgery. The tissue samples were fixed and examined by spectrofluorometry and fluorescence microscopy, yielding fluorescence spectra and microscopic fluorescence images. RESULTS: Both techniques have demonstrated significant differences between the biopsy samples harvested from hernia patients and healthy controls. The groups of fluorescence spectra were shifted relative to each other and showed maximum emission at different wavelengths after excitation with 350 nm light (arbitrarily chosen for one of the cross-link proteins). The spectra obtained for healthy controls were more homogenous, while the spectra of the hernia samples differed even between each other. In microscopic images, the difference was a more chaotic distribution of fluorophores in the samples obtained from hernia patients. CONCLUSIONS: The evidence of significant differences between the samples harvested from the same location from hernia patients and healthy controls, found by fluorescence techniques, indicates the presence of abnormalities in the connective tissue forming the rectus muscle sheath. This area is not a part of the hernial defect, therefore, we can assume that the changes can be attributed to a generalized process.

Effects of bone marrow-derived mononuclear cells on airway and lung parenchyma remodeling in a murine model of chronic allergic inflammation.

We hypothesized that bone marrow-derived mononuclear cells (BMDMC) would attenuate the remodeling process in a chronic allergic inflammation model. C57BL/6 mice were assigned to two groups. In OVA, mice were sensitized and repeatedly challenged with ovalbumin. Control mice (C) received saline under the same protocol. C and OVA were further randomized to receive BMDMC (2 × 106) or saline intravenously 24 h before the first challenge. BMDMC therapy reduced eosinophil infiltration, smooth muscle-specific actin expression, subepithelial fibrosis, and myocyte hypertrophy and hyperplasia, thus causing a decrease in airway hyperresponsiveness and lung mechanical parameters. BMDMC from green fluorescent protein (GFP)-transgenic mice transplanted into GFP-negative mice yielded lower engraftment in OVA. BMDMC increased insulin-like growth factor expression, but reduced interleukin-5, transforming growth factor-ß, platelet-derived growth factor, and vascular endothelial growth factor mRNA expression. In conclusion, in the present chronic allergic inflammation model, BMDMC therapy was an effective pre-treatment protocol that potentiated airway epithelial cell repair and prevented inflammatory and remodeling processes.

Connective tissue alteration in abdominal wall hernia.

BACKGROUND: The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations in abdominal wall hernia formation. METHODS: A computer-assisted search of the medical databases PubMed and Embase was performed, together with a cross-reference search of eligible papers. RESULTS: Fifty-two papers were included. Collagen alteration depended on the type of hernia; there were more pronounced changes in patients with a direct inguinal hernia than in those with an indirect inguinal hernia, recurrent inguinal hernia or incisional hernia. A consistent finding was a significant increase in immature type III collagen relative to the stronger type I collagen in patients with a hernia. This resulted in thinner collagen fibres with a correspondingly diminished biomechanical strength. It has been suggested that these alterations are due to variation in the synthesis, maturation or degradation of collagen by matrix metalloproteinases, in combination or alone. CONCLUSION: Hernia formation and recurrence is associated with altered collagen metabolism manifested by a decreased type I:III collagen ratio.

Biocompatibilidad de conos de Resilon y conos de gutapercha en el tejido celular de la rata: un estudio piloto / Biocompatibility of Resilon and gutta-percha cones in the subcutaneous connective tissue of the rat: a pilot study

Se implantaron en el tejido celular subcutáneo de ratas tubos de silicona conteniendo Resilon o gutapercha. Se analizó la respuesta del tejido a los 10, 30 y 60 días postimplantación. En contacto con el Resilon se observó inicialmente una banda granulomatosa rodeada por un tejido fibroso con numerosos vasos de neoformación. En contacto con los conos de gutapercha se observó un tejido fibroso joven, libre de células inflamatorias. En los tejidos circundantes se detectaron en ambos casos numerosas partículas aparentemente liberadas de los materiales estudiados. Luego de 30 y 60 días los conos estaban rodeados por tejido conectivo denso y libre de cápsulas inflamatorias. Se observó la presencia de numerosas partículas distribuidas en el tejido o fagocitadas por macrófagos, como como también dentro de la luz de vasos sanguíneos, sugiriendo la transportación de partículas hacia zonas más alejadas. Los resultados demostraron que luego de 60 días los conos de Resilon o de gutapercha analizados no provocaron reacciones inflamatorias en el tejido celular subcutáneo de la rata, aunque la intensa actividad macrofágica estimulada por la progresiva degradación de los materiales sugiere evitar en lo posible la sobreobturación con éstos.

The microvacuolar system: how connective tissue sliding works.

The term 'fascia' has been applied to a large number of very different tissues within the hand. These range from aligned ligamentous formations such as the longitudinal bands of the palmar fascia or Grayson's and Cleland's ligaments, to the loose packing tissues that surround all of the moving structures within the hand. In other parts of the body the terms 'superficial' and 'deep fascia' are often used but these have little application in the hand and fingers. Fascia can be divided into tissues that restrain motion, act as anchors for the skin, or provide lubrication and gliding. Whereas the deep fascia is preserved and easily characterized in anatomical dissection, the remaining fascial tissue is poorly described. Understanding its structure and dynamic anatomy may help improve outcomes after hand injury and disease. This review describes the sliding tissue of the hand or the 'microvacuolar system' and demonstrates how movement of tissues can occur with minimal distortion of the overlying skin while maintaining tissue continuity.