Malabsorption and microsporidia
Ronald R. Watson in NUTRIENTS and FOODS in AIDS, 2017
A coprodiagnostic technique recently described by Weber et al.17 has significantly enhanced the ease by which the diagnosis of intestinal microsporidiosis can be made. The chromotrope-based staining technique uses a procedure that is similar to the trichrome method. The chromototrope concentration in the new stain is higher and includes chromotrope 2R, fast green, and phosphotungstic acid. Identification of microsporidia spores by this coprodiagnostic technique is as sensitive and as specific as light and electron microscopy.17,18 At our institution we currently rely upon this method to identify intestinal microsporidia. Other techniques that may be useful in the coprodiagnosis are Giemsa staining of stool specimens which stain microsporidia blue, but so are other fecal elements stained with the same color and chemifluorescent agents such as calcofluor white, which require fluorescent microscopy, and are not truly specific. Several serologic assays have been described for the detection of Encephalitozoon cuniculi, a rare cause of encephalitis in humans7,19 and able to cause disseminated microsporidiosis in a number of animal species.3,20,21 These include the enzyme-linked immunosorbent assay and an indirect immunofluorescent test. Cross-reaction with sporozoa (e.g., malaria) detracts from the reliability of such serologic assays and their value as screening tests for the prevalence of microsporidial infection.22
Myocarditis
Mary N. Sheppard in Practical Cardiovascular Pathology, 2022
Examine carefully the myocytes, interstitium and intramural blood vessels. Normal myocardium is made up of approximately one third cardiomyocytes, with the remainder being interstitial cells and vascular endothelium. The myocardium is composed of cardiomyocytes joined at intercalated discs with a centrally placed nucleus (or occasionally two nuclei), often with perinuclear lipofuscin. Myocyte morphology should be assessed. The mean diameter of myocytes at the point where the cell contains a nucleus can be measured or a simple visual assessment made. Do the myocytes contain the usual amount of myofibrillary material or do they appear empty and vacuolated due to a reduction in myofibrillary content? The assessment of this feature is best carried out on H&E-stained sections. The amount and distribution of collagen should be assessed visually, or formally measured by point counting or in a computerized quantification system. The stain used to demonstrate collagen depends on personal choice and can be variants of the trichrome method, Van Gieson staining or Sirius red. Fibrosis can be focal or diffuse, subendocardial, surrounding individual myocytes, or replacement scars.
Kearns–Sayre syndrome
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop in Atlas of Inherited Metabolic Diseases, 2020
Skeletal myopathy may be evident in muscle weakness or exercise intolerance. Deep tendon reflexes may be diminished. Some patients have developed scoliosis. Cerebellar abnormality may be evident in ataxia, a broad-based gait, or dysmetria. There may be an intention tremor. Sensorineural deafness is another common neurologic manifestation of the disease. Dementia may ultimately occur. Muscle biopsy classically reveals ragged red fibers [11] when the specimen is stained with Gomori trichrome. Structural abnormality may be identified by electron microscopy. There may be aggregates of mitochondria [12]. There may be cytochrome c oxidase (COX) negative fibers, deficient pyruvate and malate oxidation and deficiency of complex I and III [7].
Exosomes derived from bone marrow mesenchymal stem cells reverse epithelial-mesenchymal transition potentially via attenuating Wnt/β-catenin signaling to alleviate silica-induced pulmonary fibrosis
Published in Toxicology Mechanisms and Methods, 2021
Enguo Zhang, Xiao Geng, Shan Shan, Peng Li, Shumin Li, Wentao Li, Meili Yu, Cheng Peng, Shijun Wang, Hua Shao, Zhongjun Du
The rats were sacrificed on the 28th day after transplantation of BMSCs and exosomes, and the lung tissues of each group were histologically examined. The results of H&E and Masson trichrome staining were demonstrated in Figure 5(A). Red clusters in H&E staining indicated extensive infiltration of inflammatory cells, and blue areas in Masson’s trichrome staining indicated collagen deposition in the rat lungs. Histological examination of lung tissues demonstrated that the alveolar structure of the control group was intact with no obvious inflammatory cell infiltration and fibrosis. However, in the lungs exposed to silica suspension, the alveolar structure in the silica model group was markedly destroyed, accompanied by a large area of inflammatory cell aggregation and silicon nodules. Compared with the control group, dark blue-stained areas were obviously increased in the silica model group. After exosomes or BMSCs transplantation, inflammatory cell aggregation and collagen fiber deposition was evident, but the area of aggregation and deposition was decreased and weaker compared to the silica model group.
Salvianolic acid A suppresses CCl4-induced liver fibrosis through regulating the Nrf2/HO-1, NF-κB/IκBα, p38 MAPK, and JAK1/STAT3 signaling pathways
Published in Drug and Chemical Toxicology, 2023
Shengnan Li, Rong Wang, Fuxing Song, Panpan Chen, Yanqiu Gu, Chun Chen, Yongfang Yuan
Liver tissues were fixed in 4% paraformaldehyde solution, paraffin-embedded, and sectioned. The liver sections were then stained with hematoxylin–eosin (H&E) for histological examination. Microscopic fields in all liver sections were randomly selected for examination using a light microscope (Nikon, Tokyo, Japan). The degree of liver fibrosis was measured as follows: 0, no obvious fibrosis; 1, fibrosis present: collagen fibers that extend from the portal triad or central vein to peripheral regions; 2, mild fibrosis: few collagen fibers extending without formation of compartments; 3, moderate fibrosis: collagen fibers with formation of ‘pseudo leaves’; and 4, severe fibrosis: many collagen fibers with thickening of partial compartments and formation of ‘pseudo lobes’. Masson's trichrome staining is usually used to discriminate collagen fibers from tissues on histological slides. Hence, in addition to H&E staining, Masson’s trichrome staining was used to microscopically estimate collagen deposition. Five different fields were randomly observed in each slice (×100). All histological examinations were performed by a very experienced pathologist blinded to the study protocol.
Design and characterization of multifaceted lyophilized liposomal wafers with promising wound healing potential
Published in Journal of Liposome Research, 2018
Amelia M. Avachat, Pooja J. Takudage
Re-epithelialization is an important phase in wound healing. This is the phase where there is a formation of an epithelial layer of the skin. Faster the formation of this layer better is the wound healing potential of the formulation. Histopathological results for re-epithelialisation in all the five groups showed that the epithelial layer was formed at the earliest in the PCW group with a thick and uniform epithelial layer which signifies good proliferation and migration of cells in presence of GTX loaded wafers. Other groups also showed re-epithelialization but better and faster results were observed in the PCW group resulting in complete closure of the wound. Collagen formation was observed by the Masson’s trichrome stain. All groups showed collagen distribution to some extent but collagen distribution was found to be uniform and thicker with comparatively good uniformity and distribution of collagen in PCW group. From the in vivo studies it could be concluded that the PCW groups demonstrated excellent results in comparison to other groups thus proving that lyophilized liposomal wafer formulation are superior over liposomal gel.
Related Knowledge Centers
- Histology
- Staining
- Acid Dye
- Polyelectrolyte
- Tissue
- Microscope
- Mallory'S Trichrome Stain
- Red Blood Cell
- Muscle
- Collagen