摘要:

Macrophages are large mononuclear phagocytes that represent the major differentiated elements of the mononuclear phagocytic system. They arise from distinct progenitors in the bone marrow, and their immediate precursors, the monocytes, emigrate from the vascular compartment into many tissues and organs where they develop into mature macrophages. The latter display diverse morphological and functional characteristics, depending on the environmental stimuli that they receive. This phenotypic heterogeneity is, therefore, the final consequence of a series of down-regulation of some cellular processes and the up-regulation of others. The kinetics of the production of macrophages and their participation in various physiological and pathological phenomena is the subject of this review.

ISSN:0191-3123    

DOI:10.3109/01913128909048488

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

A combined ultrastructural and morpnometric image analysis study was carried out on the nuclear profiles of follicular center and mantle zone lymphocytes of six cases of reactive hyperplasia in human lymph node biopsies. For accuracy of morphological observations and sampling at low magnifications, sections were mounted on formvar-covered slot grids. Measurements of nuclear profile features of small (untransformed) lymphocytes in mantle zones served as the standard for a supposed unimodal population in each case. Analysis of nuclear profile area values indicated that during lymphocyte transformation in follicular centers nuclei had a gradual and progressive increase in size and that the sampled nuclear profiles in both the mantle zone and follicular center were unimodal. Lymphocyte nuclear shape (contour index) was a more complex, and likely biologically independent, feature than nuclear area in both the mantle zone and follicular center. Nuclear profile contour indexes of mantle zone lymphocytes were more irregular than suspected and in some cases had mean values greater than those of follicular center lymphocytes. Furthermore, the frequency distribution of nuclear contour index was not normally distributed in either the follicular center or mantle zone due to the presence of a small proportion of highly irregularly shaped nuclear profiles in both sites. The results indicated that some premises of existing concepts of follicular center cells and the process of lymphocyte transformation in follicular centers were incorrect and should not be directly extrapolated to the nuclear profile characteristics in non-Hodgkin's lymphoma.

ISSN:0191-3123    

DOI:10.3109/01913128909048489

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Ultrastructural morphometric analysis was carried out on six cases of lymph node biopsies with reactive hyperplasia to establish the frequency and depth of invaginations in nuclear profiles situated in the mantle zones and follicular centers. The frequency distribution of the depth of invaginations was similar in nuclear profiles whether in the small lymphocytes of mantle zones or the small, partially transformed (centrocytes) and fully transformed (centroblasts) lymphocytes of follicular centers. Invaginated and cleaved lymphocytes were not confined to the partially transformed (centrocytic) lymphocytes of follicular centers, and nuclear profiles with invaginations bore no resemblance to those depicted in the Lukes-Collins model. A considerable proportion of mantle zone lymphocyte nuclear profiles had invaginations (ranging from 7.5% to 53.6%) and there was no difference between the frequency of deep indentations or clefts in mantle zone lymphocytes (8.1±5.4%) and the small unstimulated (9.3±5.3%) and partially transformed (8.4±1.4%) lymphocytes in follicular centers. Computer modeling of stylized nuclei with conical indentations indicated that all lymphocytic nuclei likely have multiple invaginations or groove-like creases.

ISSN:0191-3123    

DOI:10.3109/01913128909048490

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

We analyzed semiquantitatively the ultrastructural distribution of RNA by the RNase-gold method in 40 patients with acute leukemia (20 patients with AML and 20 with ALL) before the initial treatment. The number of gold particles showing the presence of RNA was high in the granular component of the nucleolus and cytoplasm but low in the fibrillar component of the nucleolus, granules, the Golgi area, and Auer bodies. The number of gold particles in the nucleolus, nucleus, or cytoplasm was higher in AML than in ALL (p<0.01). The RNase-gold method seems to be useful for evaluating the capacity of protein synthesis, maturity, or differentiation of leukemic cells.

ISSN:0191-3123    

DOI:10.3109/01913128909048491

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

In a histological and fine structural study of right atrial biopsy specimens from 31 patients with rheumatic heart disease (RHD), aged 7 to 46 years, and 11 patients with congenital heart disease (CHD), aged 3 to 36 years, nerve fibers or endings were seen by electron microscopy in 11 specimens. There was concurrence of ordinary axons along with terminals bearing pale cholinergic or dark adrenergic synaptic vesicles. Smaller and denser cholinergic vesicles suggested proliferation followed by exhaustion of such nerve endings. The closest proximity of nerve terminal to muscle fiber was about 100 nm. In one RHD specimen a“specific terminal cell”was present between a nerve ending and muscle fiber; in another a possible neuromuscular contact was developing at the surface of a regenerating small muscle fiber with a few myofilaments. Unmyelinated axons amidst increased subendocardial and subepicardial collagen, with prominent fibroblasts and depleted muscle fibers, were seen more frequently in specimens of CHD. Loss of myofibrils and accumulation of mitochondria, with infrequent formation of lipofuscin bodies, characterized degenerating muscle fibers in CHD also, although to a lesser degree than in RHD (reported earlier, 1985). The myocardial blood vessels in CHD tended to have pale swollen endothelial cells and narrowed lumen. The most severely affected cases of CHD were those with (1) a very wide atrial septal defect (ASD), (2) ventricular septal defect (VSD) with vegetations near the defect, (3) 1 infundibular pulmonary stenosis, and (4) Fallot's tetralogy.

ISSN:0191-3123    

DOI:10.3109/01913128909048492

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Human immunodeficiency virus (HIV) was detected ultrastructurally and immunohistochemically in the brain of a Japanese hemophiliac presenting AIDS encephalopathy. The encephalopathy was characterized by the multifocal occurrence of multinucleated giant cells mainly in the subcortical areas. The giant cells were identified immunohistochemically to be macrophages. HIV particles were observed in and out of the giant cells, and most of the particles ingested in the cells were membrane-bound. Some virus particles were found in pinocytic vesicles or phagocytic vacuoles, whereas the others were degradated in the lysosomes of the cells. Budding of HIV particles from the cell surface was also observed, indicating replication of the virus in vivo. These findings suggest ingestion, digestion, and replication of HIV by brain macrophages in AIDS.

ISSN:0191-3123    

DOI:10.3109/01913128909048493

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Three young children with characteristic fibroblastic tumors are presented. These comprised one case each of congenital fibrosarcoma, dermatofibrosarcoma protuberans, and fibrous hamartoma of infancy. Ultrastructural examination in each tumor revealed the presence of a peculiar intracisternal paracrystalline material that exhibited transverse periodicity between 18 and 22 nm. Elongated profiles lying within rough endoplasmic reticulum had a serpigenous outline. It is thought that this material is related to procollagen or its precursors and its presence may signify disorders of fibroblastic proliferation that may occur in fibrous tumors.

ISSN:0191-3123    

DOI:10.3109/01913128909048494

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

ISSN:0191-3123    

DOI:10.3109/01913128909048495

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

ISSN:0191-3123    

DOI:10.3109/01913128909048496

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

Pulmonary Pathologyedited by D. H. Dall and S. P. HammarSpringer-Verlag, New York-Berlin-Heidelberg-London-Paris-Tokyo: 1988The State of Water in The Celledited by W. Negendank and L. EdelmannAMF O'Hare, IL: Scanning Microscopy International

ISSN:0191-3123    

DOI:10.3109/01913128909048497

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor