An ultrastructural examination of the action of vinblastine on microtubules, neurofilaments and muscle filaments in vitro

1976 ◽  
Vol 166 (3) ◽  
Author(s):  
D.R. Tomlinson ◽  
T. Bennett
Keyword(s):  
Ultrastructural Examination ◽  
Muscle Filaments

Erythroblastic Synartesis: An Auto-immune Dyserythropoiesis

Blood ◽  
1999 ◽  
Vol 94 (11) ◽  
pp. 3683-3693 ◽  
Author(s):  
Elisabeth M. Cramer ◽  
Isabel Garcia ◽  
Jean-Marc Massé ◽  
Jean-Marc Zini ◽  
Patrick Lambin ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Normal Serum ◽  
Autologous Serum ◽  
Ultrastructural Examination ◽  
Ineffective Erythropoiesis ◽  
Rare Form ◽  
Specific Therapy ◽  
Adhesion Receptor ◽  
Glove Finger

Abstract Erythroblastic synartesis is a rare form of acquired dyserythropoiesis, first described by Breton-Gorius et al in 1973. This syndrome is characterized by the presence of septate-like membrane junctions and “glove finger” invaginations between erythroblasts, which are very tightly linked together. This phenomenon, responsible for ineffective erythropoiesis, leads to an isolated severe anemia with reticulocytopenia. In the following report, we describe 3 new cases of erythroblastic synartesis associated with dysimmunity and monoclonal gammapathy. In all cases, the diagnosis was suggested by characteristic morphological appearance of bone marrow smears, and further confirmed by electron microscopy. Ultrastructural examination of abnormal erythroblast clusters showed that these cells were closely approximated with characteristic intercellular membrane junctions. The pathogenesis of the dyserythropoiesis was modeled in vitro using crossed erythroblast cultures and immunoelectron microscopy: when cultured in the presence of autologous serum, the erythroblasts from the patients displayed synartesis, whereas these disappeared when cultured in normal serum. Moreover, synartesis of normal erythroblasts were induced by the patient IgG fraction. Immunogold labeling showed that the monoclonal IgG were detected in, and restricted to, the synartesis. A discrete monoclonal plasmacytosis was also found in the patient bone marrow. The adhesion receptor CD36 appeared to be concentrated in the junctions, suggesting that it might be involved in the synartesis. These experiments indicated that a monoclonal serum immunoglobulin (IgG in the present cases) directed at erythroblast membrane antigen was responsible for the erythroblast abnormalities. Specific therapy of the underlying lymphoproliferation was followed by complete remission of the anemia in these cases.

Echinococcus granulosus: the effects of praziquantel, in vivo and in vitro, on the ultrastructure of equine strain murine cysts

Parasitology ◽  
1988 ◽  
Vol 96 (2) ◽  
pp. 323-336 ◽  
Author(s):  
K. Sylvia Richards ◽  
D. L. Morris ◽  
D. Daniels ◽  
E. M. Riley
Keyword(s):  
Echinococcus Granulosus ◽  
Structural Organization ◽  
Drug Withdrawal ◽  
Serum Levels ◽  
Germinal Layer ◽  
Ultrastructural Examination ◽  
Hepatic Cysts ◽  
Drug Treatments

SummaryPraziquantel (500 mg/kg) administered orally to BALB/c mice with secondary equine E. granulosus daily for 21, 30 or 30 + 30 days without the drug resulted in the majority of cysts, using bench criteria of turgidity and eosin exclusion, being assessed as ‘alive’. Ultrastructural examination of 54 of these ‘alive’ cysts did not support this conclusion. They all showed increased vesiculation of the germinal layer leading, in many, to the loss of its integrity. Increased mitochondrial numbers occurred frequently. The longer drug treatments appeared to have greater effects on the germinal layer of ‘alive’ cysts and there was no detectable re-establishment of structural organization within 30 days after drug withdrawal. Subjectively, there was no substantial difference between cysts from 4-month and 9-month infections or between affected peritoneal and hepatic cysts. Tissue from collapsed cysts was necrotic. Peak serum levels of praziquantel (6430–6136 μg/l) occurred 5–10 min after drug administration (500 mg/kg) and dropped rapidly to less than 10 μg/l at 3 h. In an in vitro study at praziquantel concentrations of 1000 and 5000 μg/l over a 10-day period, most cysts were judged ‘alive’ by bench criteria but showed ultrastructurally a time- and concentration-dependent loss of integrity identical to that seen in vivo. Turgidity and eosin exclusion therefore underestimate the effect of praziquantel and the results indicate that in vitro experiments can fulfil a legitimate preliminary role in a hydatid chemotherapy programme.

Erythroblastic Synartesis: An Auto-immune Dyserythropoiesis

Blood ◽  
1999 ◽  
Vol 94 (11) ◽  
pp. 3683-3693
Author(s):  
Elisabeth M. Cramer ◽  
Isabel Garcia ◽  
Jean-Marc Massé ◽  
Jean-Marc Zini ◽  
Patrick Lambin ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Normal Serum ◽  
Autologous Serum ◽  
Ultrastructural Examination ◽  
Ineffective Erythropoiesis ◽  
Rare Form ◽  
Specific Therapy ◽  
Adhesion Receptor ◽  
Glove Finger

Erythroblastic synartesis is a rare form of acquired dyserythropoiesis, first described by Breton-Gorius et al in 1973. This syndrome is characterized by the presence of septate-like membrane junctions and “glove finger” invaginations between erythroblasts, which are very tightly linked together. This phenomenon, responsible for ineffective erythropoiesis, leads to an isolated severe anemia with reticulocytopenia. In the following report, we describe 3 new cases of erythroblastic synartesis associated with dysimmunity and monoclonal gammapathy. In all cases, the diagnosis was suggested by characteristic morphological appearance of bone marrow smears, and further confirmed by electron microscopy. Ultrastructural examination of abnormal erythroblast clusters showed that these cells were closely approximated with characteristic intercellular membrane junctions. The pathogenesis of the dyserythropoiesis was modeled in vitro using crossed erythroblast cultures and immunoelectron microscopy: when cultured in the presence of autologous serum, the erythroblasts from the patients displayed synartesis, whereas these disappeared when cultured in normal serum. Moreover, synartesis of normal erythroblasts were induced by the patient IgG fraction. Immunogold labeling showed that the monoclonal IgG were detected in, and restricted to, the synartesis. A discrete monoclonal plasmacytosis was also found in the patient bone marrow. The adhesion receptor CD36 appeared to be concentrated in the junctions, suggesting that it might be involved in the synartesis. These experiments indicated that a monoclonal serum immunoglobulin (IgG in the present cases) directed at erythroblast membrane antigen was responsible for the erythroblast abnormalities. Specific therapy of the underlying lymphoproliferation was followed by complete remission of the anemia in these cases.

Fluid secretion and microvillar ultrastructure in mosquito malpighian tubules

1989 ◽  
Vol 257 (5) ◽  
pp. R1096-R1102
Author(s):  
T. J. Bradley ◽  
C. Snyder
Keyword(s):  
Fluid Transport ◽  
Fluid Secretion ◽  
Blood Feeding ◽  
Malpighian Tubules ◽  
Primary Cells ◽  
Ultrastructural Examination ◽  
Aedes Taeniorhynchus ◽  
Physiological Limit ◽  
Secretion Rates

The Malpighian tubules of fourth instar larvae, pupae, and female adults of the mosquito Aedes taeniorhynchus were examined with regard to in vitro fluid secretion rate and the ultrastructural features of the microvillar border of the primary cells. In vitro fluid secretion rates were determined after stimulation with 5-hydroxytryptamine. While larval tubules are capable of rapid fluid secretion, the tubules of pupae exhibit very low rates of secretion, indistinguishable from 0 nl/h. The capacity to secrete fluid returns after the pupal-adult molt and is further enhanced after blood feeding. Similar results were obtained in tubules stimulated in vitro with dibutyryl adenosine 3',5'-cyclic monophosphate. Ultrastructural examination of the microvillar border of the primary cells of the Malpighian tubules revealed that the period of reduced secretion capacity in the pupal tubules is correlated with a marked reduction in microvillar volume, microvillar surface area, and mitochondrial content in the microvillar border. The results suggest that microvilli of a certain size and containing extensions of mitochondria are required for rapid fluid transport. The absence of these conditions in pupal tubules cannot be overcome by in vitro stimulation with known secretagogues and therefore represents a physiological limit on transport performance in the pupal tubules of mosquitoes.

Epizootic Gastritis Associated with Gastric Spiral Bacilli in Cheetahs (Acinonyx jubatus)

1993 ◽  
Vol 30 (1) ◽  
pp. 55-63 ◽  
Author(s):  
K. A. Eaton ◽  
M. J. Radin ◽  
L. Kramer ◽  
R. Wack ◽  
R. Sherding ◽  
...  
Keyword(s):  
Gastric Mucosa ◽  
Plasma Cells ◽  
Bacterial Species ◽  
Gastric Mucus ◽  
Ultrastructural Examination ◽  
Gastric Glands ◽  
Acinonyx Jubatus ◽  
Lymphoid Follicles ◽  
Microaerophilic Conditions

An outbreak of vomiting in a group of captive cheetahs ( Acinonyx jubatus) was investigated, and histologic examination revealed chronic gastritis characterized by infiltration of lymphocytes and numerous plasma cells and epithelial erosions. Lymphoid follicles, globule leukocytes, scattered neutrophils, and (in one animal) abscessed gastric glands were inconsistent findings. In addition, necropsy of three cheetahs revealed gastric mucosal hyperplasia. Two kinds of bacteria were identified in the stomachs of infected cheetahs. Numerous long, tightly coiled motile Gastrospirillum-like organisms were seen in gastric mucus and in Warthin-Starry-stained sections of mucosa. These bacteria could not be cultured but were transmitted to conventional mice in homogenates of gastric mucosa from infected cheetahs. Ultrastructural examination revealed helical filaments on some of these bacteria. In addition, a smaller Helicobacter sp. was isolated. This organism could be cultured in vitro under microaerophilic conditions. One or both of these bacterial species was probably responsible for the gastritis in these cheetahs.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

In Vitro Induction of Crystals of MT Protein by Vinblastine-Colcemid in Mouse Spermatids

1974 ◽  
Vol 32 ◽  
pp. 132-133
Author(s):  
John J. Wolosewick ◽  
John H. D. Bryan
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
Nuclear Ring ◽  
Rough Er ◽  
Distal Direction ◽  
In Vitro Induction

Early in spermiogenesis the manchette is rapidly assembled in a distal direction from the nuclear-ring-densities. The association of vesicles of smooth endoplasmic reticulum (SER) and the manchette microtubules (MTS) has been reported. In the mouse, osmophilic densities at the distal ends of the manchette are the organizing centers (MTOCS), and are associated with the SER. Rapid MT assembly and the lack of rough ER suggests that there is an existing pool of MT protein. Colcemid potentiates the reaction of vinblastine with tubulin and was used in this investigation to detect this protein.

Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

1982 ◽  
Vol 40 ◽  
pp. 142-145
Author(s):  
E. J. Kollar
Keyword(s):  
Connective Tissue ◽  
Oral Mucosa ◽  
Basal Lamina ◽  
Functional Derivatives ◽  
Specific Source ◽  
Dental Epithelium ◽  
Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

Immunoenzymatic demonstration of the simultaneous presence of transferrin, hemopexin and albumin in a same hepatocyte and their ultrastructural localization

1978 ◽  
Vol 36 (2) ◽  
pp. 88-89
Author(s):  
M. Kraemer ◽  
J. Foucrier ◽  
J. Vassy ◽  
M.T. Chalumeau
Keyword(s):  
Plasma Proteins ◽  
Rat Hepatocytes ◽  
Ultrastructural Localization ◽  
Carrier Proteins ◽  
Normal Cells ◽  
Adult Rat ◽  
Adult Rat Hepatocytes ◽  
Monospecific Antisera ◽  
Different Levels

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

1982 ◽  
Vol 40 ◽  
pp. 520-521
Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung
Keyword(s):  
Electron Microscopy ◽  
Corrosion Behavior ◽  
Anodic Polarization ◽  
Saline Solution ◽  
Saturated Calomel Electrode ◽  
Physiological Saline ◽  
X Ray ◽  
Physiological Saline Solution ◽  
Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

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