Malignant Melanoma of Soft Parts Involving the Head and Neck Region: Review of Literature and Case Report

Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation.     

维生素A阻抑大鼠实验性肝纤维化的病理研究

利用光镜、电镜、免疫组化和形态学定量技术动态研究维生素A对大鼠四氯化碳肝纤维化的抑制作用。结果表明,维生素A可减少四氯化碳中毒大鼠肝内纤维连接蛋白和Ⅰ、Ⅲ型胶原沉积,抑制贮脂细胞向成纤维细胞转化,并可明显地减轻肝纤维化程度。本文还对维生素A抑制肝纤维化的机理及意义作了初步探讨。     

人表皮郎格罕细胞Birbeck颗粒的超微结构观察

本文对正常人表皮郎格罕细胞MBirbeck颗粒(LG)怍了超微结构观察。计数十个细胞中146个LG的各种切面形态和出现频率,结果为:杆状占53.4％,球拍状占8.2％,泡状占7.5％,弧状占15％,环状占11％,同号状占4.8％六种。LG长约100-500nm,杆部宽为40-50nm,泡直径为70-350nm,环状的环厚为25-50am。本结果提示LG的本体结构除扁盘状和扁盘泡状外,还可能存在扁盘杯状的立体模式。     

Studies on fine structure and location of lipids in quick-freeze replicas of atherosclerotic aorta of WHHL rabbits

Summary The fine structure of intracellular and extracellular lipids in the atherosclerotic aorta of Watanabe-heritable hyperlipidemic (WHHL) rabbits was demonstrated by a quick-freeze etching technique. Many lipid droplets, with and without a membrane, were observed in the foam cells. Membrane-free droplets were observed as onionlike structure with a concentric lamellar structure surrounded by 10 nm filaments. Droplets surrounded by a limited membrane probably correspond to lipid-laden lysosomes.In the extracellular connective tissue space, marked accumulation of lipids with a vesicular structure was seen among collagen fibers. The appearance of these lipids was similar to that of lipids in lysosomes of foam cells.     

The effect of phenytoin in vitro on normal human mononuclear cells and on human lymphoblastoid B cell lines of different Ig isotype specificities

The anticonvulsant drug phenytoin, in less than cytotoxic concentrations, caused significant reductions in Ig secretion by unstimulated or EBV-stimulated normal MNC, as measured by PFC or secretion of Ig into the culture medium. Isotype-specific LBL varied in their sensitivity, the secretion of IgA (1 line) and IgG (3 lines) being reduced by phenytoin near therapeutic concentrations, whereas that of IgM (1 line) was resistant. Six-day exposure of MNC to phenytoin caused no selective depletion of or enrichment for B cells, monocytes or T cell subsets. The results suggest that the reduction in serum Ig levels reported in phenytoin-treated epileptic patients is, at least in part, due to a direct effect of the drug on the B lymphocyte. However, among EBV-activated normal MNC, those secreting IgA were no more sensitive to the drug than those secreting IgG or IgM, and other factors may, therefore, operate to cause the preferential reduction in serum IgA in phenytoin-treated patients.     

Carcinoembryonic antigen like antigen in granular cell myoblastomas

Summary A series of granular cell myoblastomas (GCM) and other benign and malignant tumours of soft tissue were examined for cytoplasmic content of carcinoembryonic antigen (CEA) by the two-layer conjugated immunoperoxidase technique. Using a commercial rabbit anti-CEA serum only granular cell myoblastomas showed positive cytoplasmic reaction. Pretreatment with periodic acid made this reaction less intense, but when the commercial rabbit anti-CEA serum was absorbed with tissue powder from normal human spleen the positive reaction was totally abolished. It is concluded that the positivity of GCM for CEA using commercial rabbit anti-CEA serum is due to the content of non-specific cross-reacting antigen (NCA) and maybe other cross-reacting glycoproteins in this tumour, and not to CEA as claimed in a previous study.     

Contractile activity of neonatal heart cells in culture derived from offspring of exercised pregnant rats

Summary 5-day-old neonatal offspring of exercised or non-exercised pregnant Sprague Dawley rats were used to prepare primary cultures of beating myocardial cells. The cells from the exercise group exhibited a slower beating rate for both single and aggregate cells; a larger cell size; an increased percentage of contracting cells; a greater capacity to form confluent monolayers, and a greater viability. It was concluded that exercise during the period of pregnancy produced morphological alterations in the myocardium of the progeny.     

Red cell flexibility,electrical resistance and viscosity of blood flowing through small glass capillaries

The influence of varying shear forces (4–10 N·cm^–2) generated by a pulsating flow of 4 cycles/min, on the longitudinal electrical resistance (R) of a blood perfused small glass capillary (I.D.=0.12 mm,l=30 mm) was determined. Red cells were stiffened by stepwise addition of bile or by sterile incubation during 24–48 h. The shear dependent changes in R were closely related to red cell flexibility and apparent blood viscosity. In normal defibrinized blood Rdecreased by about 3%, while more rigid cells evoked a shear dependentincrease in R of 1–5%. The measurements performed demonstrate that the typical shapes of the electrical signals provide more information of rheological significance of red blood cell flexibility than the results of viscosity determination alone.     

Proliferation and production of hemopoietic cells in two stages of disease: Preleukemia and overt leukemia

Summary The kinetics of erythropoietic and granulocytopoietic cell proliferation have been investigated in the same patient at two distinct stages: firstly in preleukemia presenting as pancytopenia with ineffective erythropoiesis, and secondly 2 years later in acute myelogenous leukemia. The method of investigation is based on determining the DNA synthesis rate of individual cells by means of quantitative¹⁴C-autoradiography after short-term incubation with¹⁴C-thymidine and fluorodeoxyuridine.Erythropoiesis was equally ineffective in the two stages, the rate of proliferation, however, slowed down towards the leukemic state. The production rate of myeloblasts was markedly reduced in preleukemia accompanied by a very low labelling index. In leukemia on the other hand the production rate was increased to such a degree that the leukemic myeoblast compartment is to be considered as prevailingly self-reproductive. The proliferation rate of myeloblasts was reduced already in preleukemia, and there was a further decrease in leukemia. From the point of view of cell kinetics the manifestation of leukemia in this patient is explained best by a change in the mode of proliferation: the myeloblasts change from steady state growth to behaving like an exponentially expanding population.Study performed under the association contract for hematology between EURATOM and GSF no. 089-72-I-BIAD Supported by the Deutsche Forschungsgemeinschaft: SFB 51/E-3     

Angiotensin II-induced depression of Purkinje cell firing and possible modulatory action on GABA responses

Effects of octapeptide angiotensin II (AII) were tested on cortical neurons of rat's cerebellum by means of microiontophoresis. It was observed that AII consistently depressed spontaneous firing of Purkinje cell, whereas other unidentified neurons were unaffected. When tested against responses of Purkinje cell to depressant putative neurotransmitters, namely, GABA, glycine, taurine, 5-hydroxytryptamine and noradrenaline, it was observed that AII specifically enhanced depressant action of GABA, while the responses to other substances were unaffected. Both AII-induced depression of cell firing and the AII-induced enhancement of GABA depression were antagonized by a specific GABA antagonist, bicuculline methochloride. We therefore suggest that AII exerts an inhibitory action on Purkinje cells through its modulatory action on bicuculline-sensitive GABA receptors.