Routine Electron Microscopy Research Articles

Zygotic quiescence prolongs the reproductive cycle in Berchemia sinica (Rhamnaceae)

More than two-thirds of the species in Berchemia exhibit remarkable reproductive phenology, characterized by prolonged fruit ripening and the occurrence of overlapping fruit ripening and flowering. However, the underlying reasons for these phenomena remain unknown. Therefore, this study employed routine paraffin section technology, histochemical technique and scanning electron microscopy to investigate embryo sac development, differences between male and hermaphroditic flowers, as well as the overwintering strategy in Berchemia sinica. The findings of this study revealed a significant reduction in pollen viability and the number of pollen grains per flower in hermaphroditic compared to male flowers. Following fertilization, the ovary of hermaphroditic flowers does not undergo significant enlargement but gradually enters the state of zygotic quiescence. Zygotic quiescence prolongation is the main reason for the long reproductive cycle of B. sinica, and it takes approximately 14 months for the entire cycle from flower bud differentiation to fruit ripening to complete. Long reproductive cycle and complex overwintering mechanism exhibited by B. sinica resemble those seen in species belonging to Betulaceae, Fagaceae, Tapisciaceae, and Theaceae, suggesting convergent evolution during Earth's glacial period resulted in similar adaptive structures among these groups delayed fruit ripening leads to overlap between current year's flowers with previous year's fruits. The trade-off between flower and fruit for reproductive resources may have driven evolutionary transition from ancestral hermaphroditism towards androdioecy in Berchemia.

Scanning Electron Microscopic Examination of Rainbow Trout Gastrointestinal Mucosa

Aim to study: The aim of this study was to determine the morphological characteristics of the gastrointestinal mucosa of the rainbow trout.
 Material and methods: This study was carried out on 10 rainbow trout's stomach and intestinal tissues using scanning electron microscope. In the study, 2.5% glutaraldehyde fixation and routine scanning electron microscopy procedures were applied.
 Results: The surface architecture of the gastrointestinal tract was examined in detail. It was observed that the mucosal folds in the stomach increased in number towards the pyloric region and were arranged in a configuration that allowed food to be directed to the intestine. The columnar cells of the digestive tract mucosa and the mucosal openings that allow mucus secretion were shown in detail.
 Conclusion: The gastrointestinal tract of trout, a carnivorous species, was studied in detail. The structure of the columnar cells, gastric glands and mucus openings of this system was revealed in three dimensions. The detailed anatomy of the mucosal surface, which is rapidly affected by food variation or pathological changes in fish, was revealed. This study will shed light on studies affecting the morphology of the digestive system.

Biological effects of molybdenum(IV) sulfide nanoparticles and microparticles in the rat after repeated intratracheal administration.

In this study, molybdenum(IV) sulfide (MoS2 ) nanoparticles (97 ± 32 nm) and microparticles (1.92 ± 0.64 μm) stabilized with poly (vinylpolypyrrolidone) (PVP) were administered intratracheally to male and female rats (dose of 1.5 or 5mg/kg bw), every 14 days for 90 days (seven administrations in total). Blood parameters were assessed during and at the end of the study (hematology, biochemistry including glucose, albumins, uric acid, urea, high density lipoprotein HDL, total cholesterol, triglycerides, aspartate transaminase, and alanine transaminase ALT). Bronchoalveolar lavage fluid (BALF) analyses included cell viability, biochemistry (total protein concentration, lactate dehydrogenase, and glutathione peroxidase activity), and cytokine levels (tumor necrosis factor α, TNF-α, macrophage inflammatory protein 2-alpha, MIP-2, and cytokine-induced neutrophil chemoattractant-2, CINC-2). Tissues were subjected to routine histopathological and electron microscopy (STEM) examinations. No overt signs of chronic toxicity were observed. Differential cell counts in BALF revealed no significant differences between the animal groups. An increase in MIP-2 and a decrease in TNF-α were observed in BALF in the exposed males. The histopathological changes in the lung evaluated according to a developed classification system (based on severity of inflammation, range 0-4, with 4 indicating the most severe changes) showed average histopathological score of 1.33 for animals exposed to nanoparticles and microparticles at the lower dose, 1.72 after exposure to nanoparticles at the higher dose, and 2.83 for animals exposed to microparticles at the higher dose. In summary, it was shown that nanosized and microsized MoS2 can trigger dose-dependent inflammatory reactions in the lungs of rats after multiple intratracheal instillation irrespective of the animal sex. Some evidence indicates a higher lung pro-inflammatory potential of the microform.

Immunomodulatory therapy with glatiramer acetate reduces endoplasmic reticulum stress and mitochondrial dysfunction in experimental autoimmune encephalomyelitis

Endoplasmic reticulum (ER) stress and mitochondrial dysfunction are found in lesions of multiple sclerosis (MS) and animal models of MS such as experimental autoimmune encephalomyelitis (EAE), and may contribute to the neuronal loss that underlies permanent impairment. We investigated whether glatiramer acetate (GA) can reduce these changes in the spinal cords of chronic EAE mice by using routine histology, immunostaining, and electron microscopy. EAE spinal cord tissue exhibited increased inflammation, demyelination, mitochondrial dysfunction, ER stress, downregulation of NAD+ dependent pathways, and increased neuronal death. GA reversed these pathological changes, suggesting that immunomodulating therapy can indirectly induce neuroprotective effects in the CNS by mediating ER stress.

Fatal balamuthosis in a Siberian tiger and a literature review of detection options for free-living amoebic infections in animals.

Free-living amoebae are rare causes of morbidity and mortality in humans and animals around the globe. Because the route of exposure and clinical progression of disease caused by different species of amoebae may vary in people and animals, determining the species of amoeba present is important. We describe here a fatal infection by the free-living amoeba Balamuthia mandrillaris in a Siberian tiger (Panthera tigris altaica). The 17-y-old patient had a rapid clinical decline after a peracute onset of severe lethargy, dull mentation, and anorexia. Autopsy did not identify a cause of death. Histology revealed inflammation associated with amoebic trophozoites in the brain, lungs, and iris of one eye. These amoebae were confirmed to be B. mandrillaris based on a PCR assay and sequencing. Although there are subtle morphologic differences between cyst stages of Acanthamoeba spp., B. mandrillaris, and Naegleria fowleri when present and identified on routine staining, other modalities, including PCR, immunofluorescence, electron microscopy, and immunohistochemistry, are typically utilized to confirm the pathogen involved in these cases. We review the reports of balamuthosis in animals.

Analyzing ionic liquid systems using real-time electron microscopy and a computational framework combining deep learning and classic computer vision techniques

Electron microscopy (EM) is one of the most important methods for characterizing various systems, and it is traditionally applied to static solid structures. Remarkable recent developments have opened multiple possibilities for in situ observation of different phenomena, including liquid phase processes. In contrast to routine solid-state EM measurements with static images, electron microscopy in liquids often deals with ubiquitous dynamics, which can be recorded as video streams. Providing much information about the sample, real-time EM increases the complexity of data analysis, challenging researchers to develop new, highly efficient systems for data processing. The present work proposes a framework for data analysis in real-time electron microscopy. Multiple algorithm choices are compared, and efficient solutions are described. Using the best algorithm, combining classical computer vision methods and deep learning-based denoising, the unique anisotropic effect of the electron beam in microstructured ionic liquid-based systems was discovered. The developed method provides an efficient approach for studying the structure and transformation of soft micro-scale domains in molecular liquids. The corresponding software was made publicly available, and detailed instructions to reapply it to other problems were provided.

A conventional fixation volume electron microscopy protocol for plants.

Volume electron microscopy techniques play an important role in plant research from understanding organelles and unicellular forms to developmental studies, environmental effects and microbial interactions with large plant structures, to name a few. Due to large air voids central vacuole, cell wall and waxy cuticle, many plant tissues pose challenges when trying to achieve high quality morphology, metal staining and adequate conductivity for high-resolution volume EM studies. Here, we applied a robust conventional chemical fixation strategy to address the special challenges of plant samples and suitable for, but not limited to, serial block-face and focused ion beam scanning electron microscopy. The chemistry of this protocol was modified from an approach developed for improved and uniform staining of large brain volumes. Briefly, primary fixation was in paraformaldehyde and glutaraldehyde with malachite green followed by secondary fixation with osmium tetroxide, potassium ferrocyanide, thiocarbohydrazide, osmium tetroxide and finally uranyl acetate and lead aspartate staining. Samples were then dehydrated in acetone with a propylene oxide transition and embedded in a hard formulation Quetol 651 resin. The samples were trimmed and mounted with silver epoxy, metal coated and imaged via serial block-face scanning electron microscopy and focal charge compensation for charge suppression. High-contrast plant tobacco and duckweed leaf cellular structures were readily visible including mitochondria, Golgi, endoplasmic reticulum and nuclear envelope membranes, as well as prominent chloroplast thylakoid membranes and individual lamella in grana stacks. This sample preparation protocol serves as a reliable starting point for routine plant volume electron microscopy.

Histopathological, Ultrastructural, and Immunohistochemical Findings in MYH11-Variant Visceral Myopathy.

Pathogenic mutations in the smooth muscle myosin heavy chain gene, MYH11, cause megacystis megacolon intestinal hypoperistalsis syndrome and other forms of chronic intestinal pseudo-obstruction. Evaluation of intestinal tissues from affected patients is often performed before mutational analysis, but the pathological findings of MYH11-variant visceral myopathy have not been well defined. Light microscopic, immunohistochemical, and ultrastructural findings from multiple intestinal samples from 2 patients with MYH11-variant visceral myopathy were reviewed, including MYH11-specific immunohistochemistry. The findings were compared with intestinal samples from patients with gamma-smooth muscle actin (ACTG2)-variant visceral myopathy and non-pseudo-obstruction controls. Apart from non-specific changes (e.g., muscle hypertrophy and distension-related muscularis propria necrosis), no alterations were identified by routine histopathological evaluation or electron microscopy. Immunohistochemistry with antibodies against a battery of smooth muscle proteins, including MYH11, revealed indistinguishable patterns of immunoreactivity in the muscularis propria of both patients and controls. Myopathic morphological or immunohistochemical changes may not be present in intestinal specimens from patients with MYH11-variant visceral myopathy. Molecular genetic studies should be considered for patients with chronic intestinal pseudo-obstruction and normal or non-specific pathology findings.

Assessment of susceptible Culex quinquefasciatus larvae in Indonesia to different insecticides through metabolic enzymes and the histopathological midgut

Filariasis and virus diseases that are transmitted by Culex quinquefasciatus are still a global health problem. Control of mosquito vectors with synthetic insecticides causes resistance to these mosquitoes to insecticides so that detection of susceptibility of the mosquito larval stage to insecticides is important for evaluating mosquito control programs. The aim of this study was to evaluate the susceptibility of wild-caught Cx. quinquefasciatus larvae in Jakarta, Indonesia, following exposure to temephos, malathion, cypermethrin, and deltamethrin; this was done by examining the detoxifying enzyme activities and histological damage to the larval midgut. Cx. quinquefasciatus larvae were collected from five fields in Jakarta and exposed for 24 h to temephos (1.25, 6.25, 31.25, and 156.25 ppm), malathion (0.5 ppm), cypermethrin (0.25 ppm), and deltamethrin (0.35 ppm). The larvae were then examined for acetylcholinesterase (AChE), glutathione S-transferase (GST), and oxidase activities using biochemical methods. Histological damage to the larval midgut was examined using routine histopathological methods and transmission electron microscopy (TEM). After 24 h, temephos and deltamethrin led to 100% mortality in the Cx. quinquefasciatus larvae. Temephos and malathion significantly inhibited the activity of AChE, while cypermethrin and deltamethrin significantly inhibited oxidase activity. Histologically, all insecticides damaged the larval midgut, as indicated by irregularities in the epithelial cell (ECs), microvilli (Mv), food boluses (FBs), peritrophic membranes (PMs), and cracked epithelial layers (Ep). The TEM findings confirmed that temephos and cypermethrin damage to the midgut ECs included damage to the cell membrane, nucleus, nucleoli, mitochondria, and other cell organelles. Overall, Cx. quinquefasciatus larvae in Jakarta were completely susceptible to temephos and deltamethrin. Synthetic insecticides may kill Cx. quinquefasciatus larvae through their actions on the metabolic enzyme activities and histopathological midgut.

Embryonal Tumour in the Eye of a Lady Gouldian Finch (Erythrura gouldiae) and Limited Review of Intraocular Tumours in Birds

Primary intraocular tumours are infrequent in birds. A 2-year-old male Lady Gouldian finch (Erythrura gouldiae) originally presented to the referring veterinarian after the owner noticed mild swelling of the right eye. After the eye had enlarged rapidly and bulged from the orbit, the bird was seen at the referral hospital. Enucleation was attempted but the bird died after sedation. The eye was removed and, on sectioning, a mass was seen primarily in the vitreous chamber with extension through the sclera to the retrobulbar area. After routine histology, immunohistochemistry and electron microscopy, the mass was diagnosed as an embryonal tumour of probable retinal origin. This type of tumour has rarely been documented in birds and we could find no references to any report in Estrildidae.

How innovations in methodology offer new prospects for volume electron microscopy

Detailed knowledge of biological structure has been key in understanding biology at several levels of organisation, from organs to cells and proteins. Volume electron microscopy (volume EM) provides high resolution 3D structural information about tissues on the nanometre scale. However, the throughput rate of conventional electron microscopes has limited the volume size and number of samples that can be imaged. Recent improvements in methodology are currently driving a revolution in volume EM, making possible the structural imaging of whole organs and small organisms. In turn, these recent developments in image acquisition have created or stressed bottlenecks in other parts of the pipeline, like sample preparation, image analysis and data management. While the progress in image analysis is stunning due to the advent of automatic segmentation and server‐based annotation tools, several challenges remain. Here we discuss recent trends in volume EM, emerging methods for increasing throughput and implications for sample preparation, image analysis and data management.

A new predrilling reservoir permeability prediction model and its application

The accurate prediction of sandstone permeability from variables such as porosity, composition, and texture is one of the major problems in petroleum geology. However, the application of geological variables related to diagenesis in permeability prediction models is relatively rare, especially the anomalous variations of clay content and type. This study investigates the differential control of sedimentation and diagenesis on permeability using a comprehensive analysis of cores, thin sections, routine core analysis, X-ray diffraction, and scanning electron microscopy from sandstone samples in the third member of the Weizhou Formation (Ew3), Weizhou 12-X oilfield, Weixinan Sag, Beibu Gulf Basin, China. An innovative sandstone reservoir permeability prediction model is proposed by introducing the clay factor β confining the effect of clay minerals on permeability, predicting the spatial distribution of diagenetic index (ID) using the Diagenetic Modeling System (DMS), and improving the Walderhaug permeability prediction model. The permeability of the well evaluated in the study was predicted with the relative and absolute errors changing from 0.01 mD to 192.65 mD and from 0.00 to 1.00, with an average values of 38.6 mD and 0.33, respectively, based on the sandstone reservoir permeability prediction model in Ew3. The permeability predicted by the permeability prediction model matches well with the measured permeability in Ew3. The results indicate that permeability is successfully predicted by the modified Walderhaug permeability prediction model for most sandstone reservoirs with strong diagenesis (such as anomalous changes in clay mineral types and content) under the background of a single distributary channel sedimentary microfacies. In general, anomalously high permeability zones are preferentially distributed in dominant sedimentary-diagenetic facies.

Desmoplastic reactions associated with malignant canine mammary tumours

Desmoplastic reactions or desmoplasia, characterised by proliferation of fibrotic connective tissue around tumour cells, have been described as a prognostic indicator of malignancy in human breast cancers. Desmoplasia ultimately results in deposition of collagen that shows significant differences in its density and orientation at different stages of tumourigenesis. The different collagen patterns associated with tumours are referred to as tumour associated collagen signatures (TACS) and are identified as hallmarks in human tumourigenesis. The present study was aimed to demonstrate the presence of TACS in canine mammary tumours (CMTs). The desmoplastic reactions and collagen deposition occurring in association with CMTs were analysed using routine histopathological, special staining and scanning electron microscopy techniques. Thirty excisional biopsy samples collected from malignant CMTs were utilised for studying the progression of desmoplastic reactions occurring in the tumour associated stroma.

Upregulation of C/EBP Homologous Protein induced by ER Stress Mediates Epithelial to Myofibroblast Transformation in ADTKD-UMOD.

Autosomal dominant tubulointerstitial kidney disease due to UMOD mutations (ADTKD-UMOD) results in chronic interstitial nephritis, which gradually develops into end-stage renal disease. It is believed that the accumulation of mutant uromodulin causes the endoplasmic reticulum (ER) stress, then leads to the kidney damage. But the underlying mechanism remains unclear. To find the ADTKD-UMOD patients, UMOD gene screening was performed in 26 patients with unexplained chronic interstitial nephritis, during the past 10 years in our department, and among them three ADTKD-UMOD cases were discovered. Routine pathological staining and electron microscopy sections were reviewed again to confirm their kidney lesions. Immunostaining of UMOD and ER stress marker GRP78, as well as CHOP have all been done. The strong colocalization of UMOD with GRP78 and CHOP in ADTKD-UMOD patients but not in other chronic interstitial nephritis patients had been found. Moreover in vitro experiments, ER stress induced by tunicamycin (TM) not only significantly increased the expression of GRP78 and CHOP, but also caused the epithelial to myofibroblast transformation (EMT) of renal tubular epithelial cells, evidenced by decreased expression of E-cadherin and increased expression of vimentin, and extracellular matrix (ECM) deposition, evidenced by increased expression of fibronectin (FN). CHOP knockdown could restore the upregulation of vimentin and FN induced by TM. Thus, specific activation of CHOP in renal tubular epithelial cells induced by UMOD protein might be the key reason of renal interstitial fibrosis in ADTKD-UMOD patients.

A Jurassic flower bud from China

Abstract Angiosperms may be distinguished from their gymnosperm peers by their flowers, and thus a flower is a good proxy of fossil angiosperms. However, flowers and their parts are usually too frail to be preserved in the fossil record. This makes the origin of angiosperms and their flowers the foci of controversy in botany. Eliminating such botanical controversies can only be achieved by studying related plant fossils. Applying routine scanning electron microscopy, light microscopy and micro-computed tomography (micro-CT) technologies, we document a fossil flower bud, Florigerminis jurassica gen. et sp. nov., from the Jurassic of Inner Mongolia, China. This fossil includes not only a leafy branch but also physically connected fruit and flower bud. The developmentally interpolated existence of a blooming flower between the flower bud and mature fruit in Florigerminis suggests that angiosperm flowers were present in the Jurassic, in agreement with recent botanical progress. Florigerminis jurassica underscores the presence of angiosperms in the Jurassic and demands a rethinking of angiosperm evolution.

CD226 Is Required to Maintain Megakaryocytes/Platelets Homeostasis in the Treatment of Knee Osteoarthritis With Platelet-Rich Plasma in Mice.

Platelet-rich plasma (PRP) is a platelet-based application used to treat osteoarthritis (OA) clinically. The co-stimulatory molecule CD226 is expressed in T cells, NK cells, and also platelets. However, exact effects of CD226 on platelets and whether its expression level influences PRP efficacy are largely unknown. Here, CD226fl/flPF4-Cre mice were obtained from mating CD226 fl/fl mice with PF4-Cre mice. Blood samples and washed platelets were collected from the mice eyeballs to undergo routine blood tests and transmission electron microscopy. Differentially expressed proteins were detected by iTRAQ-based proteomics analysis. Animal OA models were established through surgical destabilization of the medial meniscus (DMM) for C57BL/6 wildtype mice, followed by PRP injection to evaluate the effects of platelet CD226 on PRP efficacy. The results showed that deletion of platelet CD226 increased the number of megakaryocytes (MKs) in bone marrow (BM) but reduced MKs in spleen, combined with significantly decreased platelet amounts, α-granule secretion, and reduced immature platelets; indicating that absence of platelet CD226 may disrupt MK/platelet homeostasis and arrested platelet release from MKs. Sequencing analysis showed abnormal ribosomal functions and much downregulated proteins in the absence of platelet CD226. Autophagy-related proteins were also reduced in the CD226-absent MKs/platelets. Moreover, deletion of platelet CD226 diminished the protective effects of PRP on DMM-induced cartilage lesions in mice, and PDGF restored it. Therefore, deficiency of platelet CD226 inhibited platelet maturation, secretion, and normal ribosomal functions, which may lead to depressed PRP efficacy on OA, suggesting that CD226 is required to regulate platelet growth, functions, and its application.

Superiority of focused ion beam-scanning electron microscope tomography of cardiomyocytes over standard 2D analyses highlighted by unmasking mitochondrial heterogeneity.

BackgroundCardioprotection by preventing or repairing mitochondrial damage is an unmet therapeutic need. To understand the role of cardiomyocyte mitochondria in physiopathology, the reliable characterization of the mitochondrial morphology and compartment is pivotal. Previous studies mostly relied on two‐dimensional (2D) routine transmission electron microscopy (TEM), thereby neglecting the real three‐dimensional (3D) mitochondrial organization. This study aimed to determine whether classical 2D TEM analysis of the cardiomyocyte ultrastructure is sufficient to comprehensively describe the mitochondrial compartment and to reflect mitochondrial number, size, dispersion, distribution, and morphology.MethodsSpatial distribution of the complex mitochondrial network and morphology, number, and size heterogeneity of cardiac mitochondria in isolated adult mouse cardiomyocytes and adult wild‐type left ventricular tissues (C57BL/6) were assessed using a comparative 3D imaging system based on focused ion beam‐scanning electron microscopy (FIB‐SEM) nanotomography. For comparison of 2D vs. 3D data sets, analytical strategies and mathematical comparative approaches were performed. To confirm the value of 3D data for mitochondrial changes, we compared the obtained values for number, coverage area, size heterogeneity, and complexity of wild‐type cardiomyocyte mitochondria with data sets from mice lacking the cytosolic and mitochondrial protein BNIP3 (BCL‐2/adenovirus E1B 19‐kDa interacting protein 3; Bnip3 −/− ) using FIB‐SEM. Mitochondrial respiration was assessed on isolated mitochondria using the Seahorse XF analyser. A cardiac biopsy was obtained from a male patient (48 years) suffering from myocarditis.ResultsThe FIB‐SEM nanotomographic analysis revealed that no linear relationship exists for mitochondrial number (r = 0.02; P = 0.9511), dispersion (r = −0.03; P = 0.9188), and shape (roundness: r = 0.15, P = 0.6397; elongation: r = −0.09, P = 0.7804) between 3D and 2D results. Cumulative frequency distribution analysis showed a diverse abundance of mitochondria with different sizes in 3D and 2D. Qualitatively, 2D data could not reflect mitochondrial distribution and dynamics existing in 3D tissue. 3D analyses enabled the discovery that BNIP3 deletion resulted in more smaller, less complex cardiomyocyte mitochondria (number: P < 0.01; heterogeneity: C.V. wild‐type 89% vs. Bnip3 −/− 68%; complexity: P < 0.001) forming large myofibril‐distorting clusters, as seen in human myocarditis with disturbed mitochondrial dynamics. Bnip3 −/− mice also show a higher respiration rate (P < 0.01).ConclusionsHere, we demonstrate the need of 3D analyses for the characterization of mitochondrial features in cardiac tissue samples. Hence, we observed that BNIP3 deletion physiologically acts as a molecular brake on mitochondrial number, suggesting a role in mitochondrial fusion/fission processes and thereby regulating the homeostasis of cardiac bioenergetics.

Malignant Extrarenal Rhabdoid Tumor in a 5-Month-Old Male With Mediastinal and Heart/Great Vessel Involvement

Abstract Introduction/Objective Extrarenal rhabdoid tumor is a high-grade soft-tissue predominately pediatric malignancy with a frequency of 0.15 per million children less than 15 years. It is associated with del(22) (q11.2) with SMARCB1 loss, recognized by loss of INI-1 staining. It has distinct perinuclear hyaline inclusions; however, this feature can be present in other tumors. We describe a malignant extrarenal rhabdoid tumor involving the heart and great vessels to highlight the multiple modalities required for the diagnosis of this tumor in this unusual location. Methods We utilized routine histology, immunohistochemistry, and electron microscopy. Results This 5 -month -old male presented with respiratory distress due to a mass that invaded the heart, surrounding the great vessels. The tumor was composed of sheets of polygonal large cells with light pink to clear cytoplasm, eccentric nuclei with mild anisonucleosis, peripherally marginating chromatin, prominent nucleoli, with 2 mitoses per 10 high power field. Hyaline perinuclear inclusions were inapparent. There were frequent clusters of lymphocytes and eosinophils, with 10 percent necrosis and moderately increased vascularity. The tumor was positive for vimentin, SMA, EMA, MSA, S-100, keratin, and WT1, and negative for INI-1, CD34, ALK, AFP, PLAP, CD30, myogenin, NeuN1, synaptophysin, chromogranin, and NSE. Electron microscopy demonstrated occasional cells with perinuclear collections of intermediate filaments, some with whorls. The strong positivity for vimentin, keratin, SMA, MSA, S-100, negative staining for INA-1 and CD34, and visualization of perinuclear intermediate filament whorls by electron microscopy helped make the diagnosis of extrarenal rhabdoid tumor. Conclusion Malignant extrarenal rhabdomyosarcomas may occur in the middle mediastinum, invade the heart, occur in the first 6 months of life, and not have the typical rhabdoid cells. Diagnoses depend on multiple modalities

Transplantation of Autologous Peritoneum Using Ileal Seromuscular Flaps for Orthotopic Neobladder Reconstruction

Objective To develop an ideal surgical procedure for neobladder reconstruction in experimental porcine models. Methods Six experimental female pigs weighting 28-33 kg underwent transplantation of autologous peritoneum for bladder reconstruction under general anesthesia.The flaps were used to reconstruct the orthotopic neobladder by suturing with the edges of the triangle and neck of the remnant bladder.The ureteral catheters were removed on the 5 th postoperative day and the balloon catheter was removed on the 7 th postoperative day.Voiding behaviour was monitored.The animals were euthanized at week 12 for routine pathology,immunohistochemistry,and electron microscopy. Results All the pigs survived after the surgery,and no postoperative complication such as peritonitis,intestinal obstruction,or urinary fistula was observed.All the peritoneum-ileum composite free valves survived after transplantation.Voiding behaviour was normal after catheter removal,and the urine was clear.At autopsy,reconstructed bladders were healthy.Pathological examination showed the neobladder had been covered by continuous urothelium while the peritoneum disappeared and showed no ileal mucosa regrowth and residual.Scanning electron microscope showed the transitional cells of neobladder were complete and orderly,and the urothelium around suture border was continuous and showed no malposition. Conclusions Reconstruction of bladder by autologous peritoneum and ileal seromuscular flaps is an ideal approach in the experimental pigs as it can prevent regrowth of ileal epithelial cells and avoid the complications of conventional enterocystoplasty.Its clinical application deserves further investigations.

Investigating mitochondrial autophagy by routine transmission electron microscopy: Seeing is believing?

Mitochondrial autophagy is affected in many diseases. In the past few years, the multiple-steps process of selective degradation of mitochondria has been dissected in details by combining outcomes from different approaches. Perhaps one of the most rigorous methods to clearly visualise mitochondria undergoing autophagic engulfment and degradation, is transmission electron microscopy (TEM). In this opinion paper, we want to give a brief summary of the mitophagic process, and by which means mitophagy can be addressed, including TEM analysis. We will report examples of autophagy and mitophagy-related TEM images, and discuss how to decipher the different steps of the mitophagic process by routine TEM. In our opinion, this technique can be used as a powerful confirmatory approach for mitochondrial autophagy and can provide details of the organelle fate throughout the course of mitophagy with no substantial sample manipulation.