Ultrastructure of the Lamina Propria of the Human Ductuli Efferentes and Ductus Epididymidis

The cellular and connective tissue constituents of the lamina propria of the ductuli efferentes and the ductus epididymidis of prepubescent, adult and senescent men were studied by means of electron microscopy. Layers of contractile cells showing features of smooth muscle cells, alternate with interstitial layers of connective tissue fibers. Additionally to collagenous fibers, in the interstitial layers three types of elastic system fibers, oxytalan, elaunin and elastic, were evident, differing by their varying amount of elastin. Oxytalan fibers, lacking the amorphous component elastin, were present in almost all intercellular spaces along the excurrent duct system, closely related to the contractile cells. They were the only type of elastic system fibers recognizable in the prepubescent epididymal lamina propria. However, in the adult and senescent men, elastin deposits were observed in the middle and outer layers of the lamina propria. In these cases the elaunin and elastic fibers appeared to increase with the gradual proximo-distal thickening of the subepithelial coat of contractile cells. In senescent men, only in few cases the epididymal lamina propria showed some alterations. It is suggested that these changes are not related to age but more likely to the state of individual testicular function. The functional significance of the special architecture of the epididymal lamina propria is discussed.     

Organization and cellular biology of the perichondrial ossification groove of ranvier: a morphological study in rabbits.

The perichondrial ossification groove of Ranvier, a circumferential groove in the periphery of the epiphyseal cartilage, was studied in rabbits whose ages ranged from one week to eight months using light and electron microscopy, autoradiography after labeling with 3H-thymidine, 3H-proline, and 3H-glucosamine, and histochemical staining for proteoglycans and alkaline phosphatase. By these methods, three groups of cells were identified within the groove: 1. A group of densely packed cells deep in the groove, which are the progenitor cells for the osteoblasts that form the bone bark, a cuff of bone surrounding the epiphyseal growth-plate region and the adjacent part of the metaphysis. 2. A group of more widely dispersed, relatively undifferentiated mesenchymal cells and fibroblasts, some of which are chondroblast precursors that probably contribute to appositional chondrogenesis and growth in width of the epiphyseal cartilage. 3. Fibroblasts and fibrocytes among sheets of highly oriented and organized collagen fibers which form a fibrous layer that is continuous with the outer fibrous layer of the periosteum and with the perichondrium. This layer also sends fibers into the epiphyseal cartilage and anchors the periosteum firmly to the epiphyses as bone growth proceeds.     

Ultrastructural analysis of human penile corpus cavernosum Its significance in tumescence and detumescence

The erectile tissue from 15 normal and impotent male patients was studied by electron microscopy to determine if any ultrastructural features could contribute to the basic understanding of the physiology of penile erection and detumescence. It was found that the endothelium lining the cavernous lacunae contained both contractile elements and Weibel-Palade bodies which have a possible role in vasoconstriction. Within the trabeculae of the cavernous body there was an abundance of elastin as well as oxytalan and elaunin fibers around bundles of smooth muscle. With these elements affording an anchorage system for contraction of smooth muscles within the trabeculae, an alternate contraction of smooth muscles and endothelium could account for the erectile and detumescent states.     

Ultrastructure of the human interspinous ligament and ligamentum flavum. A preliminary study

The ultrastructure of ligamenta flava (LF) and interspinous ligaments (ISL) obtained from four patients who underwent surgery for vertebral fracture (control group) and five patients operated for disc herniation was studied. The fine structure of LF was composed of elastic and elaunin fibers. Small diameter collagen fibrils were found between the elastic system fibers. The ISL was constituted predominantly of collagen fibrils. Elastic fibers were seen in the most ventral part of the ligament. In ISL and LF of the control group, the cells were fibroblastic-like cells. Chondrocytes were present only near their attachment sites. The proteoglycans were demonstrated between the collagen fibrils, and they appeared to form a regular interfibrillar linking. In ligaments obtained from patients with disc herniation, several modifications were found. The fibroblasts transformed into chondrocytic cells, which were surrounded by a pericellular matrix rich in proteoglycan filaments. A few cells that had suffered necrosis were found. Alterations in the collagen-proteoglycans arrangement also were evidenced. The proteoglycan filaments were randomly oriented to the collagen fibrils.     

Adrenergic innervation of human middle cerebral artery. Ultrastructural observations

The innervation of the human middle cerebral artery is studied with transmission electron microscopy using the chromaffin reaction technique. Adrenergic nerve fibers and related terminals, with granular electrodense neurotransmitter vesicles, are confined to the tunica adventitia-tunica media transitional zone and the outer layers of the media. These findings may indicate the presence of an adrenergic vasoconstrictor system for circulation control in the human middle cerebral artery.     

皮肤老化过程中弹力纤维的形态学变化

目的探讨年轻人正常皮肤、自然老化皮肤、光老化皮肤的弹力纤维形态学特征，建立评判皮肤弹力纤维损伤程度及治疗药物对其修复程度的简单、实用方法。方法分别取年轻人光保护皮肤（年轻人正常皮肤）、老年人光保护皮肤（自然老化皮肤）以及老年人光暴露皮肤（光老化皮肤）进行甲醛溶液固定，石蜡包埋、切片，醛品红染色（Gomori染色法）。结果在年轻人光保护皮肤耐酸纤维、前弹力纤维及成熟的弹力纤维组成结构完整清晰的弹力纤维网络。老年人光保护皮肤的弹力纤维损伤相对较轻，主要表现为真皮乳头处耐酸纤维数量明显减少，真皮中上层弹力纤维轻度增粗及片段化。老年人光暴露皮肤的弹力纤维损伤明显，表现为真皮乳头处耐酸纤维消失，真皮浅层和中层弹力纤维明显增粗、扭曲、断裂、分支、形成团块。结论年轻人正常皮肤、自然老化皮肤、光老化皮肤的弹力纤维形态学各具有明显的特征，Gomori染色法是评价皮肤老化过程中弹力纤维损伤效果及治疗药物对其修复效果的简单、实用方法。     

A light and electron microscopic and immunohistochemical study of human arachnoid villi

The structure of human arachnoid villi was investigated by light and electron microscopy with the aid of immunohistochemical techniques. The human arachnoid villi examined were basically composed of four portions: a fibrous capsule, an arachnoid cell layer, a cap cell cluster, and a central core. The arachnoid cell layer encompassing the central core was mostly covered by the thin fibrous capsule with an endothelial investment. However, the fibrous capsule was often absent at the apical portion of the villus and a factor VIII-related antigen stain failed to confirm the investment of endothelial cells. Instead, the arachnoid cell layer abutted directly upon the lumen of a lateral lacuna or the sinus. The arachnoid cell layer was thickened in places, forming cap cell clusters; it usually consisted of outer and inner zones. On vimentin staining, the former was slightly positive while the latter was strongly positive. The central core contained a network of arachnoid cells intermingled with connective tissue fibers and was in continuity with the cranial subarachnoid space. Electron microscopy showed that the arachnoid cells contained a larger number of intermediate filaments in the inner zone than the outer zone. Ultrastructural immunohistochemical localization showed that vimentin was localized at the intermediate filaments and desmosomal plaques of the arachnoid cells. The arachnoid cells showed a marked variety in both the cell forms and the number of intermediate filaments or desmosomes, depending on their location.     

Slipped capital femoral epiphysis: a pathological study. I. A light microscopic and histochemical study of 21 cases

Core biopsy specimens of slipped proximal femoral epiphyseal growth plates and of normal controls were examined by light microscopy and histochemistry. Slipped growth plates showed diminished cellularity with an overall excess of matrix as well as severe disorientation and misalignment of chondrocytes. Decrease in number of argyrophilic fibers in the longitudinal septa suggested deficiency in collagen. Histochemical staining of slipped plates did not deviate from normal except in severely deformed areas. Anatomic and histochemical observations did not conclusively support or exclude biochemical or biomechanical factors in the etiology of epiphyseal slipping.     

Changes of elastic fibers in musculoskeletal tissues of Marfan syndrome: a possible mechanism of joint laxity and skeletal overgrowth.

The aim of the study was to analyze by histochemical, ultrastructural, and morphometric methods the musculoskeletal tissues in three humans affected with Marfan syndrome. Histochemical and morphometric data demonstrated that the content of elastic fibers in the perichondrium, periosteum, and knee capsule of the individuals with Marfan syndrome was dramatically reduced in comparison with control tissues. Ultrastructurally the elastic fibers appeared fragmented and indented, because of the presence of discontinuous aggregates of elastin among randomly dispersed filaments. These abnormalities of the articular capsule argue that these fibers could be functionally incompetent to resist normal stress, predisposing to joint laxity. Moreover, alterations in both perichondrium and periosteum seems to support our previous hypotheses about the control of long-bone growth exerted by elastic fibers.     

A LIGHT and ELECTRON MICROSCOPICAL STUDY OF COLLAGEN DEGENERATION

1. an electron microscopical study of skin with severe collagen degeneration showed that there are changes in elastic, collagen and reticular fibres which lead to a great reduction in the amount of organized fibrous tissue present in the dermis. 2. the collagen fibrils, which are normally formed by tightly packed, strictly aligned filaments, were degraded with the release of the filaments to form disorientated masses. 3. it is suggested that the material which stains like elastin in the dermis is derived from both elastin and collagen. there is hypertrophy and dispersion of elastic fibres, which have degraded collagen added to their surface. there is also a change of narrow bands of the degraded collagen masses to a material looking like elastin. 4. the walls of the small blood-vessels are profoundly altered, and it is considered that these changes would alter their permeability and therefore affect the nutrition of the overlying epidermis.     

Aging of the elastic and collagen fibers in the human cervical interspinous ligaments.

BACKGROUND CONTEXT: The ligaments consist of collagen bands intermingled with elastic fibers that support hundreds of pounds of stress per square inch. In the spine the basic functional unit comprises vertebrae, intervertebral disc and ligament tissues. The interspinous ligaments with the function of limiting the spine flexion are exposed to a traumatic and degenerative process that promotes pain or instability. It has been shown that aging induces structural changes to capsular, fascial and ligamentous structures, mainly to the elastic and collagen fibers. However, the relative changes with age in elastic and collagen fibers have not been quantified. PURPOSE: Examine the changes in the arrangement and amount of the elastic and collagen fibers of the human cervical interspinous ligament and attempt to correlate them with age. STUDY DESIGN/SETTING: Histomorphometric analysis of ligament samples harvested during surgery. PATIENT SAMPLE: We studied the dorsal portion of this ligament from 17 patients aged 16 to 69 years. OUTCOME MEASURES: Fraction of collagen and elastic fibers with linear regression analysis correlating fraction versus age. METHODS: The elastic and collagen fibers were identified by selective staining methods, and a blinded investigator using an image analysis system performed the histomorphometry. RESULTS: There is an age-related progressive increase in collagen and mature and elaunin elastic fibers responsible to elasticity. However, these elastic fibers showed structural degenerative changes with aging. Furthermore, there is an age-related decrease of oxytalan elastic fibers responsible to resistance. CONCLUSIONS: The aged interspinous ligament showed loss of elasticity that could alter the flexion limiting of the vertebral column.     

Studies on the arrangement of the collagenous fibers in infant epiphyseal plates using polarized light and the scanning electron microscope

The architecture of the collagenous fibers in epiphyseal plates of infantile long bones was investigated using polarized light and scanning electron microscope. In the zone of columnar cartilage the collagenous fiber bundles are arranged longitudinally in the intercolumnar cartilaginous septa. In addition to this main longitudinal orientation, some of the fibers branch off at an acute angle and flow through the cartilage columns surrounding rhombus-shaped groups of chondrocytes. In the area adjaced to the inert cartilage the collagen fibers become curved and form a network of arcades. In the zone of inert cartilage the collagenous fibers are arranged in a honeycomb-like fashion. The importance of the arrangement of the collagen fibers to the loading strength of the epiphyseal plate is discussed.     

Histologic characteristics of the human prepuce pertaining to its clinical behavior as a dual graft

The aim of this study was to investigate the unique histologic structure of the normal human prepuce, paying particular attention to the resemblance and dissimilarities between the inner (ie, mucosa) and outer (ie, skin) layers. Histologic sections were stained using hematoxylin-eosin and Van Gieson stains. Transmission electron microscopy was used to evaluate the ultrastructure. Dense capillary networks can be observed in both the upper and lower dermal zones. The dermis lacks a dense collagenous zone. Melanocytes could not be observed in the mucosa. Elastin fibers and bundles were very abundant and dense. Early edema formation can be explained by the loose character of the dermal structure. Better graft "take" in mucosal grafts may be the result of the dense vascular dermal network. Mild hyperpigmentation can be explained by the limited number of melanocytes. However, this can also be observed in mucosal grafts, despite the absence of melanocytes. This may be solely the result of inflammatory hyperpigmentation, which can be seen in skin grafts. The abundance of elastin fibers in the prepuce may be the reason behind the superior wound contraction inhibition.     

Expression of nitric oxide synthase immunoreactivity in the human female intramural striated urethral sphincter

PURPOSE: While we have recently detected neuronal nitric oxide synthase (nNOS) immunoreactivity in a heterogeneous population of human male urethral striated muscle, to our knowledge the association of nNOS in the female counterpart is unknown. We investigated the association of nNOS with female urethral striated muscle and re-investigated muscle fiber types. MATERIALS AND METHODS: Cryostat sections were taken from the middle third of 4 human female urethras. Nicotinamide adenine dinucleotide phosphate diaphorase histochemistry and nNOS immunohistochemistry were performed. Muscle fiber types were identified by myofibrillar adenosine triphosphatase histochemistry and fast twitch troponin T immunohistochemistry. The association between nNOS immunoreactivity and muscle fiber type was analyzed. RESULTS: Positive staining for nicotinamide adenine dinucleotide phosphate diaphorase histochemistry and nNOS immunoreactivity were recognized in the sarcolemma of 43.9% of female urethral striated muscle fibers. Immunoreactivity for fast twitch troponin T immunohistochemistry was demonstrated by 2% of the striated fibers. The use of myofibrillar adenosine triphosphatase showed that all fibers darkly stained uniformly at a pH of 9.6, 4.6 and 4.3, suggesting that they were myofibrillar intermediate muscle fibers. The results allowed the differentiation of 2 subgroups of fibers, namely smaller fibers (modal diameter 10.1 to 15.0 microm.) without nNOS immunoreactivity and larger fibers (modal diameter 15.1 to 20.0 microm.) with nNOS immunoreactivity. CONCLUSIONS: To our knowledge female urethral striated muscle has for the first time been found to consist of myofibrillar intermediate fibers and nNOS was positively localized in the sarcolemma of a subgroup of the fibers. This study provides a basis for further investigation into female urethral striated sphincter function and changes in pathological conditions.     

The vertebral cartilaginous endplate of the preadult rhesus monkey (Macaca mulatta). A correlative scanning electron-and light-microscopic study

The microanatomy of the preadult rhesus monkey (Macaca mulatta) vertebral cartilaginous endplate was investigated with scanning electron microscopy and light microscopy. The plate contains three zones: an outer noncalcified zone adjacent to the intervertebral disc, a middle zone of acellular islands of calcification surrounded by cellular hyaline cartilage, and an inner zone resembling a cartilaginous growth plate. Fibers from the annulus fibrosus pass through an outer zone into the middle zone. Trabecular bone of a developing annular epiphysis is present in the periphery of the plate. Vertical columns of cartilage traverse the nuclear region of the endplate and occasionally surround blood vessels. These columns and their associated blood vessels probably represent notochordal and fetal blood vessel remnants.     

Elastin fibers display a versatile microfibril network in articular cartilage depending on the mechanical microenvironments

Elastin fibers are major extracellular matrix macromolecules that are critical in maintaining the elasticity and resilience of tissues such as blood vessels, lungs and skins. However, the role of elastin in articular cartilage is poorly defined. The present study investigated the organization of elastin fiber in articular cartilage, its relationship to collagen fibers and the architecture of elastin fibers from different mechanical environments by using a kangaroo model. Five morphologies of elastin fibers were identified: Straight fiber, straight fiber with branches, branching fibers directly associated with chondrocyte, wave fiber and fine elastin. The architecture of the elastin network varied significantly with cartilage depth. In the most superficial layer of tibial plateau articular cartilage, dense elastin fibers formed a distinctive cobweb‐like meshwork which was parallel to the cartilage surface. In the superficial zone, elastin fibers were well organized in a preferred orientation which was parallel to collagen fibers. In the deep zone, no detectable elastin fiber was found. Moreover, differences in the organization of elastin fibers were also observed between articular cartilage from the tibial plateau, femoral condyle, and distal humerus. This study unravels the detailed microarchitecture of elastin fibers which display a well‐organized three‐dimensional versatile network in articular cartilage. Our findings imply that elastin fibers may play a crucial role in maintaining the integrity, elasticity, and the mechanical properties of articular cartilage, and that the local mechanical environment affects the architectural development of elastin fibers. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1345–1353, 2013     

Ultrastructural changes induced by experimental subarachnoid haemorrhage and 6-hydroxydopamine in cat cerebral arteries

Summary Transmission electron microscopy of the middle cerebral artery from cats exposed to subarachnoid injection of blood 3 and 7 days before, showed several damage of the vascular ultrastructure. The intima was thickened with swelling and vacuolization of endothelial cells, with a plump appearance and disruption of tight junctions. The cellular surface was corrugated and the subendothelial space contained proliferating and vacuolated smooth muscle cells capped by elastin and collagen fibres. The internal elastic lamina was also corrugated and disrupted. The adventitial changes were axonic cytoplasmic and mitochondrial swelling, virtual absence of synaptic vesicles, and disruption of the outer axonal membrane, suggesting denervation of cerebral vessels. With administration of 6-hydroxydopamine (6-OHDA), similar ultrastructural changes were observed in the adventitia. These observations indicate that denervation induced by subarachnoid bleeding could be involved in the pathophysiology of cerebrovascular spasm. Subarachnoid haemorrhage, but not 6-OHDA, affects also intima and tunica media, suggesting other mechanisms, in addition to denervation, can participate in the vasospasm.     

主动脉夹层患者升主动脉中层弹性蛋白与弹力纤维的变化

目的:探讨Stanford A型主动脉夹层(AD)升主动脉中层弹性蛋白和弹力纤维变化。方法:收集10例Stanford A型AD患者术中获取的升主动脉管壁组织标本与10例脑死亡捐献手术中或冠状动脉旁路移植术中获取的正常升主动脉管壁组织标本,用Westernblot法检测两组标本中膜层弹性蛋白表达;用EVG弹力纤维染色分析两组升主动脉中膜层弹力纤维形态及含量。结果:Westernblot结果显示,AD升主动脉中膜层弹性蛋白含量较正常升主动脉明显降低[(0.32±0.07)vs.(1.12±0.17),t=6.722,P=0.003]。EVG染色结果显示,AD升主动脉中膜层弹力纤维形态和排列紊乱,弹力板层断裂、丢失,而正常升主动脉中膜弹力纤维排列紧密、有序,弹力板结构完整,层次分明;AD升主动脉中膜层弹力纤维含量较正常升主动脉明显降低[(85762.8±106.2)vs.(164482.8±161.4),t=5.902,P0.001]。弹性蛋白与弹力纤维含量在AD与正常升主动脉中膜层均呈明显正相关(r=0.953、0.973,均P0.001)。结论:StanfordA型AD患者升主动脉中层弹性蛋白和弹力纤维含量下降,弹力纤维形态和结构紊乱,该改变可能在AD的发生中起了重要作用。     

Legg-Calvé-Perthes disease. Histochemical and ultrastructural observations of the epiphyseal cartilage and physis

Biopsy specimens of the lateral aspect of the femoral head and neck were obtained from five children with Legg-Calvé-Perthes disease and were studied using histochemistry and electron microscopy. Beneath the normal articular cartilage there was a thick zone of hyaline (epiphyseal) cartilage containing sharply demarcated areas of hypercellular and fibrillated cartilage with prominent blood vessels. The fibrillated cartilage was strongly positive to alcian blue, weakly positive to periodic acid-Schiff, and positive to aniline blue. The interterritorial matrix in the hypercellular areas was weakly positive to both alcian blue and periodic acid-Schiff. Ultrastructural examination of these areas revealed many irregularly oriented large collagen fibrils and variable amounts of proteoglycan granules. These results suggest that in the fibrillar areas there are: (1) a high proteoglycan content, (2) a decrease in structural glycoproteins, and (3) a different size of collagen fibrils from that of normal epiphyseal cartilage. The hypercellular areas had a decrease in proteoglycans, glycoproteins, and collagen. The lateral physeal margin was often irregular, with a marked reduction of collagen and proteoglycan granules, and contained numerous large lipid inclusions. CLINICAL RELEVANCE: The abnormal areas in the epiphyseal cartilage of patients with Legg-Calvé-Perthes disease have different histochemical and structural properties from normal cartilage and from fibrocartilage. This suggests that the disease could be a localized expression of a generalized, transient disorder of epiphyseal cartilage that is responsible for delayed skeletal maturation. The cartilage lesions are similar to those seen in the vertebral plates in patients with juvenile kyphosis. Whether the epiphyseal cartilage abnormalities are primary or are secondary to ischemia remains uncertain; however, it appears that the collapse and necrosis of the femoral head could result from the breakdown and disorganization of the matrix of the epiphyseal cartilage, followed by abnormal ossification.