Metabolic and ultrastructural renal changes in adult Wistar rats fed by a cafeteria diet

ABSTRACT Purpose: To evaluate, by quantitative and qualitative methods, the glomerular ultrastructure in Wistar rats fed a cafeteria diet. Methods: Male Wistar rats were divided into two groups at 21 days of age: control (C, n = 10) and cafeteria diet (CAF, n = 8). The animals were followed up until 5 months of age, followed by euthanasia. The blood, kidneys, and fat deposits--epididymal, retroperitoneal, and subcutaneous--were extracted and analyzed. Data were analyzed by Student's t test, and p < 0.05 was considered statistically significant. Results: The cafeteria diet promoted glucose intolerance, hyperglycemia (p < 0.0001), and deposition of retroperitoneal fat (p < 0.005). Scanning electron microscopy revealed that the length of the foot process was similar in both groups. The quantitative analyses by transmission electron microscopy revealed that the cafeteria diet reduced the thickness of the glomerular basement membrane (p < 0.05). Conclusions: The intake of lipids and simple carbohydrates were found to be associated with alteration in the glomerular ultrastructure. However, more studies are needed to evaluate not only the effects of high-protein and high-fat diets on components of the glomerular filtration barrier, but also renal physiology.

Cross-sectional evaluation of the saccharin transit time test for primary ciliary dyskinesia: did we discard this tool too soon?

ABSTRACT BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare and heterogeneous disease that is difficult to diagnose and requires complex and expensive diagnostic tools. The saccharin transit time test is a simple and inexpensive tool that may assist in screening patients with PCD. OBJECTIVES: This study aimed to compare changes in the electron microscopy findings with clinical variables and saccharin tests in individuals diagnosed with clinical PCD (cPCD) and a control group. DESIGN AND SETTING: An observational cross-sectional study was conducted in an otorhinolaryngology outpatient clinic from August 2012 to April 2021. METHOD: Patients with cPCD underwent clinical screening questionnaires, nasal endoscopy, the saccharin transit time test, and nasal biopsy for transmission electron microscopy. RESULTS: Thirty-four patients with cPCD were evaluated. The most prevalent clinical comorbidities in the cPCD group were recurrent pneumonia, bronchiectasis, and chronic rhinosinusitis. Electron microscopy confirmed the clinical diagnosis of PCD in 16 of the 34 (47.1%) patients. CONCLUSION: The saccharin test could assist in screening patients with PCD due to its association with clinical alterations related to PCD.

McCune-Albright syndrome - A case report with transmission electron microscopy.

McCune - Albright syndrome is a genetic disease with cutaneous mosaicism caused by post-zygotic activating mutations in GNAS locus, it has a triad of fibrous bone dysplasia, café-au-lait macules and precocious puberty. We examined a 22-year-old female patient with café au lait spot in right side of the abdomen, with a chessboard - like distribution, extending to right thigh with geographical contours, she has also an ovarian cyst, scoliosis and truncal obesity. Biopsies were taken from the hyperpigmented area and processed for light microscopy and for transmission electron microscopy. Light microscopy showed increased melanin pigment with HE staining. Immunohistochemistry with melanocytic markers (HMB-45 and Melan-A) revealed a normal number of melanocytes. Transmission electron microscopy demonstrated normal epidermal structures, such as desmosomes, cytokeratin filaments and hemidesmosomes. With high magnifications an irregular melanossomal contour was seen, with some indentations in their outline.

Age-related changes in pancreatic histology and ultrastructure in rats / 中华老年医学杂志

Objective:To investigate age-related histological and ultrastructural changes of the pancreas in Sprague-Dawley(SD)rats, and to provide a theoretical basis for the high incidence of pancreatic diseases in the elderly.Methods:Thirty 6-month-old specific pathogen-free male SD rats were fed until 6, 12, 18 and 25 months of age.Five rats of each age group were randomly selected, killed and then sampled to make histological(HE staining)and electron microscopic sections to observe age-related changes in pancreatic histology and ultrastructure.Results:The pancreatic tissue of rats showed increasing fibrosis with age, especially around the duct.Fat infiltration of the pancreatic tissue also increased with age( H=15.88, P=0.001). With the increase of age, the number(density)of pancreatic islets decreased gradually( F=3.55, P=0.039), but the average cross-sectional area of islets increased significantly( F=7.76, P=0.002), and the round and oval islets became irregular.Nuclear pyknosis, mitochondrial dehydration, mitochondrial swelling, and dilatation and loose organization of rough endoplasmic reticula were observed in the cytoplasm of pancreatic acinar cells and islet beat cells in aged rats.With the increase of age, the number of zymogen granules at the apical pole of pancreatic acinar cells of rats decreased( F=9.73, P<0.001), and the average area and total area of granules were significantly decreased( F=6.51, P=0.001; F=22.18, P<0.001); The number of non-senescent mitochondria and senescent mitochondria in the cytoplasm of acinar cells increased significantly( H=8.22, P=0.045; H=32.95, P<0.001); The amount of proinsulin in islet beta cells was significantly decreased( F=16.20, P<0.001). Conclusions:With aging, the rat pancreas exhibits a series of degenerative manifestations(stromal hyperplasia, adipose tissue infiltration, decreased numbers of zymogen granules in acinar cells, increases in the number of senescent mitochondria, reduced islets and reduced proinsulin in islet beta cells), while there are some compensatory phenomena(increasing numbers of islets and non-senescent mitochondria).

Ultrastructural aspects of the skin in lipoid proteinosis (Urbach-Wiethe disease)

Abstract Lipoid proteinosis is a rare autosomal recessive disease, characterized by hyaline deposits of PAS-positive material in tissues due to mutations in the ECM1 gene. This study evaluated the ultrastructure of the skin of a 6-year-old child affected by this condition. The light microscopy identified PAS-positive hyaline deposits, which were more intense in the papillary dermis. Scanning electron microscopy of the dermis showed a compact papillary dermis and fibrillar deposits in the middle dermis. Transmission electron microscopy clearly showed the deposition of fibrillar material in the dermis, forming clusters adherent to elastic fibers, between the collagen bundles and the collagen fibers, and also filling up the cytoplasm of dermal fibroblasts.

Ultrastructural aspects of the skin in lipoid proteinosis (Urbach-Wiethe disease).

Lipoid proteinosis is a rare autosomal recessive disease, characterized by hyaline deposits of PAS-positive material in tissues due to mutations in the ECM1 gene. This study evaluated the ultrastructure of the skin of a 6-year-old child affected by this condition. The light microscopy identified PAS-positive hyaline deposits, which were more intense in the papillary dermis. Scanning electron microscopy of the dermis showed a compact papillary dermis and fibrillar deposits in the middle dermis. Transmission electron microscopy clearly showed the deposition of fibrillar material in the dermis, forming clusters adherent to elastic fibers, between the collagen bundles and the collagen fibers, and also filling up the cytoplasm of dermal fibroblasts.

Transmission and scanning electron microscopy of cutis rhomboidalis

Abstract Cutis rhomboidalis nuchae was assessed in a 65-year-old patient. Optical microscopy showed basophilic agglomerations in the reticular dermis with decreased elastic fibers. Trans- mission electron microscopy showed elongated, curved and fragmented structures, and in their interior the presence of electron-dense lumps was reduced and irregular, similar to modified elastic fibers, whereas the collagen fibers had a normal aspect. Scanning electron microscopy showed deposits between the bundles of collagen, resembling pebbles or stones. These findings demonstrate that, at one stage of the disease, the collagen remains normal and the alterations are seen in the elastic tissue.

Transmission and scanning electron microscopy of cutis rhomboidalis.

Cutis rhomboidalis nuchae was assessed in a 65-year-old patient. Optical microscopy showed basophilic agglomerations in the reticular dermis with decreased elastic fibers. Transmission electron microscopy showed elongated, curved and fragmented structures, and in their interior the presence of electron-dense lumps was reduced and irregular, similar to modified elastic fibers, whereas the collagen fibers had a normal aspect. Scanning electron microscopy showed deposits between the bundles of collagen, resembling pebbles or stones. These findings demonstrate that, at one stage of the disease, the collagen remains normal and the alterations are seen in the elastic tissue.

[A summary of 70 years' development of diagnostic techniques of ophthalmic pathology in China].

With the development of medical science, new techniques and methods of ophthalmic pathology are constantly emerging, which has greatly promoted the advancement of ophthalmology. The Chinese Journal of Ophthalmology has witnessed the growth of ophthalmic pathology in China since its founding 70 years ago. This article reviews the development of diagnostic techniques of ophthalmic pathology in China and speculates their future direction.（ Chin J Ophthalmol， 2020， 56: 641-645）.

Simulated biological fluid exposure changes nanoceria's surface properties but not its biological response.

Nanoscale cerium dioxide (nanoceria) has industrial applications, capitalizing on its catalytic, abrasive, and energy storage properties. It auto-catalytically cycles between Ce3+ and Ce4+, giving it pro-and anti-oxidative properties. The latter mediates beneficial effects in models of diseases that have oxidative stress/inflammation components. Engineered nanoparticles become coated after body fluid exposure, creating a corona, which can greatly influence their fate and effects. Very little has been reported about nanoceria surface changes and biological effects after pulmonary or gastrointestinal fluid exposure. The study objective was to address the hypothesis that simulated biological fluid (SBF) exposure changes nanoceria's surface properties and biological activity. This was investigated by measuring the physicochemical properties of nanoceria with a citric acid coating (size; morphology; crystal structure; surface elemental composition, charge, and functional groups; and weight) before and after exposure to simulated lung, gastric, and intestinal fluids. SBF-exposed nanoceria biological effect was assessed as A549 or Caco-2 cell resazurin metabolism and mitochondrial oxygen consumption rate. SBF exposure resulted in loss or overcoating of nanoceria's surface citrate, greater nanoceria agglomeration, deposition of some SBF components on nanoceria's surface, and small changes in its zeta potential. The engineered nanoceria and SBF-exposed nanoceria produced no statistically significant changes in cell viability or cellular oxygen consumption rates.

Cutaneous collagenous vasculopathy: light and transmission electron microscopy

Abstract Cutaneous collagenous vasculopathy is a rare acquired idiopathic microangiopathy characterized by progressive development of diffuse asymptomatic telangiectasias and histologically by accumulation of collagen type IV around the affected vessels. It is diagnosed by its clinical history, confirmed by light microscopy with collagen-specific immunostaining. We report a case of a patient with extensive acquired telangiectasias on the left arm, clinically resembling unilateral nevoid telangiectasia. Dilated blood vessels with thickened walls were observed in the dermis. Immunohistochemistry with collagen IV antibodies revealed marked collagen deposition around the vessels, confirming the diagnosis. Transmission electron microscopy observed duplicate and triplicate vascular basal membrane associated with deposition of amorphous material around the membranes.

[Pathological features of levator aponeurosis in patients with involutional blepharoptosis].

Objective: To observe pathological features of levator aponeurosis in patients with involutional ptosis. Methods: A prospective study. Twenty-nine consecutive patients with involutional blepharoptosis who underwent levator aponeurosis advancement surgery for blepharoptosis correction were enrolled at Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University from 2007 to 2013. Twenty-nine specimens of the levator aponeurosis were obtained during surgery. Hematoxylin-eosin staining, Van Gieson staining, Masson staining, immunohistochemistry and transmission electron microscope observations were performed to observe the features of levator aponeurosis. Twelve normal specimens of fresh levator aponeurosis were obtained from Beijign Tongren Eyebank as control group. Mann-Whitney's U-test and multiple linear regression were used for statistical analysis. Results: Among the enrolled cases, there were 19 males and 10 females;14 cases were diagnosed with moderate ptosis and 15 cases with severe ptosis;9 cases involved with both eyes, 9 cases with right eyes, and 11 cases with left eyes. The mean age was 59 years. Among the 12 normal cases, there were 5 males and 7 females. The mean age was 56 years. Histopathological observation showed fascicle disruption(+++, ++, + 24, 2, 3 vs. 0, Z=-5.666, P<0.001), scarcity of cross-striations(+++, ++, + 23, 2, 4 vs. 0, Z=-5.582,P<0.001), collagen fibers hyperplasia(+++, ++, + 15, 10, 4 vs. 0, Z=-5.223,P<0.001), fatty infiltration(+++, ++, + 24, 5, 0 vs. 0, Z=-5.671,P<0.001), and a decrease of myoglobin expression(+++,++,+,- 9, 1, 1, 15 vs. 8, 1, 0, 0, Z=-3.004, P=0.005) in levator aponeurosis. Transmission electron microscope recorded presence of collagen fiber hyperplasia and cellular degeneration including mitochondria swelling and hyperplasia, vacuoles, lipid droplets, nucleus pycnosis, chromosome condensation, disintegrated organelles, myeloid body and autophagy. Multivariate linear regression showed a correlation between fat infiltration and age(ß=0.425, P=0.043) while suspicious related clinical features as independent variables and observed histopathological features as dependent variables. Conclusion: The levator aponeurosis appears to be involved with muscle fiber degeneration, collagen fiber hyperplasia and cellular degeneration in patients with involutional blepharoptosis. (Chin J Ophthalmol, 2018, 54: 671-677).

Apolipoprotein A1 localization in sperms and its antibody′s effect on human sperm function / 中华检验医学杂志

Objective To investigate the presence of apolipoprotein A 1 (APOA1) and its function in human spermatozoa. Methods The expression assays for APOA 1 were carried out by immunofluorescence and Western blotting in human sperm cells . Set up a blank control group , rabbit polyclonal IgG group , which contain anti-APOA1 antibody 10 μg/ml, 20 μg/ml and 40 μg/ml, to treat normal semen samples and incubated at 37 ℃for 1 h, 2 h and 3 h.The progressive motility of spermatozoa was determined bya computer-assisted motion analyzer ( CASA ) , apoptosis rate by flow cytometry and ultrastructural changes by electron microscopy .Comparisons of sperm progressive motility and apoptosis rate were performed by independent sample t tests.Results The study showed APOA1 protein mainly located in the sperm head , the molecular size was 31000.A significant decline in sperm progressive motility was observed after 1,2 and 3 hours of incubation with APOA1 antibody.There was a statistically significant difference between the blank control group and the APOA 1 antibody concentration of 20 μg/ml and 40 μg/ml groups [ 1 hour after incubation , blank control group ( 68.65％ ±15.70％) with 20 μg/ml group (48.45％±5.20％), 40 μg/ml group(39.25％±7.89％), t=2.442, 3.345 , both P<0.05;2 hours after incubation, blank control group(55.33％±10.12％) with 20 μg/ml group(28.68％±11.70％), 40μg/ml group(18.13％ ±10.52％), t=3.445, 5.097,both P<0.05; 3 hours after incubation, blank control group(35.73％±14.08％) with 20μg/ml group(15.53％±8.42％), 40μg/ml group(9.98％± 7.08％), t=2.462, 3.268,both P<0.05].After incubation 2 hours, the percentage of apoptotic cells increased from 16.02％ ±4.28％ in the blank control group to 21.72％ ±2.67％ ( 20 μg/ml APOA1 antibody)and 28.01％±3.93％(40 μg/ml APOA1 antibody), respectively (t=3.177, 5.834, both P<0.01).Treatment with 40 μg/ml APOA1 antibody for 4 hours resulted in major morphological changes to sperm cells observed by electron microscope , including membrane distension ,vacuole formation and different periods of apoptosis cells .Conclusion APOA1 plays an important role in maintaining sperm motility and survival rate,however the mechanism needs further study .

Ultrahistopathological features of six cases of symmetrical acrokeratoderma under transmission electron microscope / 中华皮肤科杂志

Objective To investigate ultrahistopathological features of symmetrical acrokeratoderma.Methods Biopsy specimens were obtained from skin lesions and perilesional normalappearing skin of 6 patients with symmetrical acrokeratoderma,as well as from normal skin of 3 healthy volunteers.Then,these skin specimens were subjected to transmission electron microscopy (TEM).Results TEM showed obviously thickened stratum corneum,irregular morphology of keratinocytes and discontinuous cornified envelope.Aggregation and abnormal arrangement of keratin filaments occurred in all epidermal layers.Many vacuoles of different sizes were observed in the transitional zone between the stratum corneum and stratum granulosum.Hypogranulosis,abnormal shape and different sizes of keratohyalin granules,and reduction of membrane-coating granules were found in the stratum granulosum.Increased melanocytes with a large number of stage Ⅳ melanosomes in the cytoplasm were observed in the basal layers.Moreover,there was infiltration of a few lymphocytes in the superficial dermis.Perilesional normal-appearing skin tissues showed similar but milder ultrastructural changes.Conclusion Abnormal metabolism of keratins,epidermal differentiation complex proteins and lipids may exist in skin lesions of symmetrical acrokeratoderma,which may contribute to epidermal thickening and impairment of skin barrier function.

Ultrastructural aspects of pseudoxanthoma elasticum

Abstract: We report the ultrastructural findings in a case of a 72-year-old black woman with confluent yellowish papules in the cervical region. She had no comorbidities. Ophthalmological examination, electrocardiogram, and echocardiogram were normal. Hematoxylin-eosin staining of the affected skin showed strong alterations in the mid-dermis with irregular clumps of eosinophilic material and loss of the normal parallel arrangement of collagen bundles. Orcein staining revealed that the elastic fibers lost their normal linear configuration, showing clump fragmentation, sometimes forming square structures. Transmission electron microscopy showed aberrant elastic fibers with an irregular outline and heterogenic inner structures. We also observed small elastic fibers. Collagen fibers showed a normal structure with irregular distribution. Scanning electron microscopy revealed important disorganization of collagen fibers and small stone-like deposits measuring around 5 µm associated with bigger structures ranging from 10-16 µm. Higher magnification revealed that these small stone-like structures were sometimes polyhedral-shaped or squared.

A histomorphometric study of unmyelinated fibers of the fibular nerve in Wistar rats / Histomorfometria das fibras amielínicas do nervo fibular em ratos Wistar

ABSTRACT There are few histomorphometric studies on the unmyelinated fibers of the fibular nerve in rats, and the number of experimental studies using this nerve has been increasing in the last years. Sixty-two percent of the endoneurial area from 10 fibular nerves of adult Wistar rats was scanned by electron microscopy, and digitized. The total number of unmyelinated axons (1.882 ± 271) was significantly lesser, and their axon diameters (0.2 µm to 2.8 µm) significantly higher than that determined in previous studies. The histogram peaked at 1 µm. The differences could be due to the nerve sampled area, the number and the age of the animals evaluated, and the laboratory techniques used. This study brings new and referential data to be used in experimental investigations involving histomorphometric evaluation of the rat fibular nerve.

RESUMO Embora o nervo fibular de ratos venha sendo incluído progressivamente em maior número de estudos experimentais nos últimos anos, há poucos estudos a respeito das suas fibras amielínicas. Os nervos fibulares de 10 ratos Wistar adultos foram avaliados através de microscopia óptica e eletrônica. Varredura sistemática através de microscopia eletrônica de transmissão das áreas fasciculares da porção distal no nervo foi realizada. Em média, 62% da área endoneural foi digitalizada. O número total de axônios amielínicos encontrados (1.882 ± 271) foi significativamente menor e as medidas dos diâmetros axonais (0,2 µm a 2,8 µm) maiores do que o determinado em estudos prévios. O pico do histograma foi constituído por fibras de 1µm. As diferenças podem ser devidas à amostragem de maior área endoneural, ao número e à idade dos animais avaliados, e as técnicas laboratoriais utilizadas. Os dados obtidos podem ser considerados referenciais para o nervo fibular de ratos Wistar adultos.

Mechanism of Escherichia coli injury under UV disinfection / 军事医学

Objective To study the inactivation kinetics and injury mechanism of Escherichia coli under UV disinfection in drinking water.Methods The inactivation kinetics of E.coli ATCC 25922 was determined by plate count methods in the UV disinfection experiment.The morphology,cell membrane permeabilization and injury of biological macromolecules were observed under a transmission electron microscope (TEM).The rate of ONPG hydrolysis and changes in activities of antioxidant enzymes were observed Raman spectroscopy.Results the changes of damaged cells involved morphological damage such as loss of the structural integrity of the wall and membrane,condensation of cellular material and leakage of significant amounts of cytoplasmic material,a more than four-fold increase of cell membrane permeabilization and damage to the structure of protein,nucleic acids and phospholipid.Conclusion UV disinfection can lead to a multi-target damage.

Histopathological characteristics of melasma / 中华皮肤科杂志

Objective To investigate histopathological and ultrastructural differences between melasma tissues and normal skin tissues around pigmented nevus. Methods Eight patients with melasma and 16 patients with facial pigmented nevus were included in this study. Two millimeter punch biopsies were taken from melasma lesions and adjacent normal skin of facial pigmented nevus. Biopsy specimens were then subjected to hematoxylin?eosin (HE) staining, Fonton?Masson staining, Verhoeff?van Gieson staining, and immunohistochemical staining with monoclonal antibodies HMB45 and NKI/beteb. Transmission electron microscopy was used to observe the tissue specimens. Semi?quantitative analysis was performed under a light microscope, and quantitative analysis by using a computerized image analysis system. Results Histopathological study revealed increased number of melanin granules mainly in the basal and prickle cell layers, sometimes in the dermis, in melasma tissues compared with normal skin tissues. Melanocytes were only observed in the epidermis of melasma tissues. Compared with normal skin tissues, melasma tissues showed no significant difference in the quantity of melanocytes, but a significant increase in the volume, staining intensity and dendrite number of melanocytes. In all of the 8 patients with melasma, mild to moderate lymphocytic infiltration was observed in the superficial dermis and around capillaries, with moderate telangiectasis in the superficial dermis. Electron microscopy revealed that there were more melanosomes in melanocytes and keratinocytes, and melanocyte dendrites extended into the dermis in melasma tissues. Conclusions Among the 8 patients, there were only two types of melasma, i.e., epidermal melasma and mixed melasma, and no dermal melasma was found. Inflammation and telangiectasis may induce or aggravate melasma.

Optimization of ultrastructure observation of human embryonic stem cell-derived retinal pigment epithelial cells / 中华实验眼科杂志

Background Normal ultrastructure is the anatomical basis of retinal pigment epithelial(RPE) cells to perform normal physiological function.At present the precipitation method is often used to detect the ultrastructure of RPE cells with transmission electron microscopy(TEM).Objective The aim of this study was to explore a simple and feasible approach to examine the ultrastructure of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells.Methods hESCs were induced and differentiated into RPE cells by the spontaneous differentiation method,and the expressions of microphthalmia associated transcription factor MITF and paired-box gene 6 (PAX6),specific protein of RPE cells,in the cells were detected by immunofluorescence assay.hESC-RPE cells were inoculated into Transwell filter,and the ultrastructure of the cell sheet was examined under the TEM.Then the ultrastructure of the cell sheet specimens was compared with those of hESC-RPE cells from cell precipitation and RPE cell specimens of 90-day-old Long Evans rats.Results MITF and PAX6 were positively expressed in hESC-RPE cells.The normal ultrastructure were visible in the RPE cells of rats under the TEM,including apical microvilli,polarized melanin granules,cellular nucleus,basement membrane and intercellular junctions,and the ultrastructure of hESC-RPE cell sheet on Transwell was similar to the RPE cells in rats.However,only scatter melanin granules,nonpolar nucleus and scanty microvilli were observed under the TEM in the hESC-RPE cells by cell precipitation method.Conclusions Without digestion process,hESC-RPE cell sheet on Transwell can retain the normal ultrastructure of hESC-RPE cells under the TEM,with a more simple and reliable advantage.

Atypical infantile genital Molluscum contagiosum

Abstract Genital molluscum contagiosum is rare in children. We report a molluscum contagiosum around the vulva and anus of 9-year-old girl, which has atypical presentations and was finally confirmed by histopathological and electron microscopy findings.