Sequential studies of rat urinary bladder epithelial lesions induced by ifosfamide (Z4942)

Urinary bladder damage caused by ifosfamide in male F344 rats was studied by light microscopy and scanning electron microscopy. Ifosfamide was injected intraperitoneally at doses of 30, 60 and 120 mg. per kg. body weight, and rats were killed at several intervals following treatment. The changes in the epithelium observed by light microscopy and scanning electron microscopy following ifosfamide injection were compared to those observed following cyclophosphamide injection. Necrosis and exfoliation of the urinary bladder epithelium occurred after day 1 of ifosfamide treatment and were followed by regenerative hyperplasia. This hyperplasia was reversible. A dose response was evident in the number and size of lesions induced and the time of regeneration and repair. Scanning electron microscopy disclosed short, uniform microvilli on the luminal surface of cells during the early phases of hyperplasia. These microvilli persisted for only 1 day, from days 1 to 7, and days 1 to 12 respectively, following injection of 30, 60 and 120 mg. per kg. of ifosfamide. The hyperplastic lesions also contained cells with pleomorphic microvilli and ropy or leafy microridges on their surfaces. These findings after ifosfamide administration were similar to those reported to be induced in the urinary bladder by cyclophosphamide.     

A morphometric investigation of the duodenal mucosa of normal,vitamin D-deficient,and vitamin D-replete rats

Light and electron microscopy were utilized to determine differences in morphology and size in duodenal villi and microvilli from normal, vitamin D-deficient, and vitamin D-replete rats. An increase in villus diameter and surface area was observed in vitamin D-deficient rats. Administration of vitamin D reversed the increase in diameter but the height of villi increased resulting in longer, thinner villi without a significant change in surface area. A decrease in microvillus surface area seen in vitamin D-deficient animals was reversed by the administration of vitamin D.     

A morphometric investigation of the duodenal mucosa of normal, vitamin D-deficient, and vitamin D-replete rats

Light and electron microscopy were utilized to determine differences in morphology and size in duodenal villi and microvilli from normal, vitamin D-deficient, and vitamin D-replete rats. An increase in villus diameter and surface area was observed in vitamin D-deficient rats. Administration of vitamin D reversed the increase in diameter but the height of villi increased resulting in longer, thinner villi without a significant change in surface area. A decrease in microvillus surface area seen in vitamin D-deficient animals was reversed by the administration of vitamin D.     

Scanning electron microscopy of polypoid cystitis--a reversible lesion of the human bladder

Scanning electron microscopy was performed on forceps biopsies from 13 patients with catheter-associated polypoid cystitis. Pleomorphic microvilli, which varied considerably in appearance, were found on surface cells of all cases with polypoid cystitis. Practically all of the characteristics of pleomorphic microvilli assigned earlier to bladder tumor cells in humans were identified on specimens from patients with polypoid cystitis. Pleomorphic microvilli were not observed in the bladder biopsies from control patients. The appearance of pleomorphic microvilli was consistent with reversible lesions of the human bladder and they are not specific markers of pre-neoplastic hyperplasia or malignancy.     

Scanning electron microscopy of exfoliated malignant and non-malignant human urothelial cells

Midstream urine samples were taken from 35 patients with histologically diagnosed urinary bladder carcinoma, from 27 patients without history or sign of malignancy or infection in the urinary tract, and from eight patiens with cystitis. The urine was filtered through Millipore filters, or Nuclepore filters, pore size 5.0 microns, on which the cells were caught. From the same patients biopsies were obtained from different anatomic regions of the urinary bladders as well as from the carcinomas that were present. The filters and the biopsies were examined with scanning electron microscopy (SEM). The exfoliated cells trapped on the filters were in good morphological condition. Idential characteristics of the cell surface morphology were recognized in the biopsies and the exfoliated cells from each patient. In non-malignant cases the cells displayed the regional morphological charcteristics of the urinary bladder. Bacteria and an increased number of red and white blood cells were attached to the cell surface of numerous exfoliated cells in patients with cystitis, but no pleomorphic microvilli were detected in these patients. In cases of malignancy exfoliated cells with pleomorphic microvilli on their surface were detected. A large majority of the exfoliated cells shed in the urine with pleomorphic microvilli on their surfaces still retained enough regional surface characteristics to determine their origin. Some of the cells were completely covered with pleomorphic microvilli and it was impossible to determine their origin.     

Ultrastructural and functional abnormalities of intestinal and renal epithelium in the SHR

Intestinal calcium transport, renal tubular calcium reabsorption, and plasma 1.25 (OH)2 vitamin D3 (calcitriol) levels have all been reported to be diminished in the spontaneously hypertensive rat (SHR) compared with its genetic control the Wistar Kyoto rat (WKY). In the present study, absorptive duodenal and renal tubular epithelia of 12- to 14-week-old male SHR and WKY were examined by electron microscopy to determine whether such disturbances could be related to structural abnormalities. Patchy loss of microvilli in both duodenal and proximal tubular epithelia was observed in the SHR, whereas brush border membrane was entirely normal in the WKY. Irregular spaces were observed between the basal aspects of SHR intestinal epithelial cells and their basement membrane. In addition, the average height of duodenal and renal microvilli was reduced in the SHR. Two specific markers of the brush border membrane, alkaline phosphatase and villin, as well as the cytoplasmic vitamin-D dependent calcium-binding proteins, CaBP9K and CaBP28K were determined. Duodenal alkaline phosphatase activity was reduced in the SHR, compared with the WKY: 0.145 +/- 0.002 vs. 0.186 +/- 0.002 IE/min.microns 3 x 10(3) brush border, mean +/- SEM, N = 10 pairs, P less than 0.001. However, duodenal villin expression was not different from that of the WKY. Duodenal CaBP9K and renal CaBP28K content was diminished in the SHR: 21.0 +/- 0.80 vs. 29.9 +/- 2.19 micrograms/mg protein, N = 6 pairs, P less than 0.01 for duodenum, and 4.47 +/- 0.39 vs. 7.67 +/- 0.54 micrograms/mg protein, N = 6 pairs, P less than 0.001 for kidney. These data showing structural and functional abnormalities of intestinal and kidney cells in the SHR appear to reflect a disorder of transporting epithelia which may be either intrinsic or related to reduced circulating calcitriol.     

Scanning electron microscopy of changes in the urinary bladder in dogs treated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)

Summary The fine structures of the bladder mucosa during BBN carcinogenesis and of bladder tumors induced by BBN in dogs were examined by scanning electron microscopy. Normal dog bladder mucosa was covered with polygonal superficial cells with peaked microridges, but no microvilli. Microridges and uniform microvilli were observed in hyperplastic mucosa. In low grade papillary tumors induced by low doses of BBN, pleomorphic microvilli predominated. In dogs which received high doses of BBN, bizarre pleomorphic microvilli and blebs were observed in papillary lesions, whereas bumpy surfaces with thick short microvilli were observed in non-papillary lesions. These sequential changes which were observed in dog bladder mucosa during BBN carcinogenesis parallelled the changes that occurred in the process of chemical carcinogenesis in rodents, and dog bladder tumors were similar to those of rodents and of human bladder cancers.     

Achieving better patency rates and neoendothelialization in 1-millimeter polytetrafluoroethylene grafts by varying fibril length and wall thickness.

This study evaluates the effects of different fibril lengths and wall thicknesses on patency and neoendothelialization in 1 mm inner diameter polytetrafluoroethylene (PTFE; Gore-Tex) grafts and highlights the importance of longer fibril lengths and matching wall thicknesses. Fibril lengths tested were 30, 60, and 90 microns. The grafts had a wall thickness ranging from 0.18 to 0.34 mm. Ninety-six grafts were implanted in the infrarenal aorta of Wistar rats. Grafts were harvested at various intervals and examined macroscopically, by light microscopy, and by scanning electron microscopy. Both the highest patency rates and the best grades of neoendothelialization were observed in the 90 microns fibril length grafts, while the lowest of both were seen in the 30 microns fibril length grafts. From this study we conclude that 90 microns fibril length PTFE can be considered a valid micrograft for bridging arterial defects in microvascular reconstructive procedures.     

Scanning electron microscopy of hyperplastic and neoplastic human prostate

Summary Acinar cells of neoplastic prostate tissues are more heterogeneous in size and shape than benign hyperplastic cells when observed by scanning electron microscopy. Three types of acinar cells are recognizable by surface structure, cells with microvilli, cells without microvilli, and cells with membrane ruffles. The pitted cells previously seen in BPH tissues are probably artifactual. The identity of the crater cells is still in question.Supported by Grant CA15417-02 from National Prostatic Cancer Project     

Does extracorporeal shock wave lithotripsy injure the female reproductive tract?

Female reproductive tract lies near the distal ureter where extracorporeal shock wave lithotripsy (ESWL) of calculi is performed. The question whether ESWL may induce morphological changes in ovary, tube or uterus should be investigated in animal experiments. The female reproductive system of 28 Wistar rats was exposed to 600 or 1200 shock waves. After 24 hours or 35 days the animals were sacrificed and examined by light microscopy and scanning electron microscopy (SEM). Acute after ESWL 2/14 rats revealed minimal subcapsular bleeding in the ovaries. SEM showed a desquamation of superficial cells and a loss in microvilli. In long-term groups there was no morphological lesion. Besides the correlation between healthy and atretic follicles were unchanged. In animal experiment no sign of long lasting changes in female reproductive tract after ESWL could be observed.     

Peritoneal morphology in children treated by continuous ambulatory peritoneal dialysis

Fifty peritoneal biopsies (PB) from 35 patients with end-stage renal disease, treated by continuous ambulatory peritoneal dialysis (CAPD) and aged 2 months to 18 years, were examined by light microscopy (n=50) and/or scanning electron microscopy. PB were performed during surgical procedures immediately before the start of, during, or after the cessation of CAPD treatment. PB from 15 children without renal disease undergoing laparatomy were examined similarly. Before the start of CAPD, a scarcity and shortening of the mesothelial microvilli was observed by scanning electron microscopy. During and after CAPD, variable alterations of mesothelium, interstitium and capillaries were found. The mesothelial layer was absent in all 5 PB obtained during episodes of active peritonitis. In patients treated by CAPD for longer than 6 months, mesothelial denudation was observed more frequently (6/11) than in children treated for shorter periods (1/7) (P<0.08). Fibrosis of the peritoneal membrane was present in about 50% of patients during or after the cessation of CAPD without impairment of peritoneal function. No correlation was found between the presence of fibrosis and the frequency of peritonitis or the duration of CAPD treatment.     

Morphology of the peritoneal membrane during continuous ambulatory peritoneal dialysis

In the last 3 years we performed 52 peritoneal biopsies (PB) in 31 patients on continuous ambulatory peritoneal dialysis (CAPD). Samples of the parietal peritoneum were obtained either during insertion of the catheter or while it was being repositioned or removed. PB was performed in 13 patients before initiating CAPD and in 27 after 7-49 months of CAPD while 7 had PB during peritonitis, and, again, in 5 of these cases, PB was repeated after 1-4 months for light, electron transmission, and scanning electron microscopy. BP after CAPD showed that mesothelial cells were irregularly spaced, and at times we observed alterations in the cellular structure. Rarely were these cells degenerating, while rarefaction and in many cases complete absence of microvilli were observed. In some cases the submesothelial layers showed rarefaction of the connective tissue and sclerosis. During peritonitis, PB showed more alterations with marked degeneration and in some cases necrosis of the mesothelium and alterations of connective tissue. PB performed some months after peritonitis showed only a partial regression of these alterations and sclerotic patches, and no microvilli were noted in the mesothelium.     

Ultrastructural changes in renal tubules associated with glomerular bleeding

Renal biopsies from ten patients presenting with macroscopic or heavy microscopic hematuria, shown to be glomerular in origin, were examined by light and electron microscopy. All biopsies showed erythrocytes within tubules by light microscopy and, in five cases, there were morphologic features of acute tubular necrosis. In four biopsies there was clear evidence by electron microscopy of uptake of erythrocytes by renal tubular epithelial cells, associated with some blunting of epithelial microvilli, vacuolar change and increased lysosomal content. Associated with erythrophagocytosis, the subsequent pathway of erythrocyte destruction within renal tubular epithelial cells closely resembled the hemolytic pathway described in macrophages of the reticuloendothelial system.     

Morphology of syncytiotrophoblast cells in testicular tumors

Syncytiotrophoblastic cells were identified in a teratocarcinoma of the testis by light microscopy using the semi-thin sectioning technique. An electron microscope study confirmed them to be syncytial. Many irregularly shaped nuclei lying in a honeycombed cytoplasm were observed, while the free margins contained microvilli. These cells are morphologically similar to syncytiotrophoblasts of the normal placenta. The presence of syncytiotrophoblastic cells in testicular tumours means a worse prognosis than would otherwise be concluded on the basis of the particular tumour concerned.     

Size of metallic and polyethylene debris particles in failed cemented total hip replacements.

Reports of differing failure rates of total hip prostheses made of various metals prompted us to measure the size of metallic and polyethylene particulate debris around failed cemented arthroplasties. We used an isolation method, in which metallic debris was extracted from the tissues, and a non-isolation method of routine preparation for light and electron microscopy. Specimens were taken from 30 cases in which the femoral component was of titanium alloy (10), cobalt-chrome alloy (10), or stainless steel (10). The mean size of metallic particles with the isolation method was 0.8 to 1.0 microns by 1.5 to 1.8 microns. The non-isolation method gave a significantly smaller mean size of 0.3 to 0.4 microns by 0.6 to 0.7 microns. For each technique the particle sizes of the three metals were similar. The mean size of polyethylene particles was 2 to 4 microns by 8 to 13 microns. They were larger in tissue retrieved from failed titanium-alloy implants than from cobalt-chrome and stainless-steel implants. Our results suggest that factors other than the size of the metal particles, such as the constituents of the alloy, and the amount and speed of generation of debris, may be more important in the failure of hip replacements.     

腹膜透析对人腹膜形态结构的影响

目的 探讨腹膜透析（腹透）对人腹膜，重点在间皮层形态结构的影响及其意义。方法 采用光镜，扫描电镜和透射电镜对10例正常对照者，12例尿毒症非透析患者以及10例腹透患者的腹膜活检标本进行形态学观察。结果 尿毒症非透析患者腹膜的结构与正常对照者相似，而腹透患者的腹膜形态结构随着透析时间而呈进行性改变。主要表现为间质细胞表面微绒毛减少，消失，间皮细胞从基底膜脱落直至完全消失，最后只剩下裸露的纤维结缔组织。结论 腹膜透析可引起腹膜的形态学明显改变，这可能是长期腹膜透析引起腹膜衰竭的原因之一。进一步深入研究腹膜结构与功能间关系能为人们了解长期腹透对腹膜影响的病理生理机制并进而寻找保护腹膜的手段提供理论依据。     

Preliminary study of hydrophilic hydrogel intraocular lens implants in cats

Soft hydrophilic intraocular lenses (10Ls) made of anaminopolyamide (Duragel) and a hydroxyethylmethylmethacrylate (HEMA) hydrogel polymer were implanted in cats and followed for six weeks. During surgery, a 45-second purposeful contact between the lens surface and the corneal endothelium was made. During the course of the experiment, all implanted eyes maintained clear IOLs and manifested a continuing mild iritis. Scanning electron microscopy of the corneas revealed numerous microvilli but no damage to cell membranes. Scanning electron microscopy of the aminopolyamide IOLs revealed fibroblast growth on the surface. No fibroblast growth was noted on the surface of the HEMA I0Ls. These experiments suggest that soft hydrogel IOLs may be better than conventional hydrophobic acrylic I0Ls in minimizing endothelial contact damage. However, the observation of corneal microvilli may indicate a mild adverse reaction to the hydrogels, possibly from impurities. Fibroblast growth on the aminopolyamide may also be due to an ocular inflammatory response to the material or impurities. Hydrogel IOLs may be of interest because of their semirigid physical properties and greater safety on contacting the endothelium. However, considerable attention must be given to polymer composition and polymer purification.     

Morphological changes of microvilli on different surfaces of epithelial cells in the rat bladder treated withN-butyl-N-(4-hydroxybutyl) nitrosamine

This study investigates morphological changes of microvilli occurring on different surfaces of epithelial cells, including luminal surfaces, intercellular surfaces, and basal cell surfaces adjacent to the basement membrane (BM), in the rat bladder treated withN-butyl-N(4-hydroxybutyl) nitrosamine (BBN) by transmission electron microscopy (TEM). The present results showed that the microvilli were observed not only on the luminal surfaces of epithelial cells but also on the intercellular surfaces and basal cell surfaces adjacent to the BM following administration of BBN. There were a variety of morphological changes of microvilli on the luminal surfaces, intercellular surfaces and basal cell surfaces adjacent to the BM, respectively. It is suggested that the microvilli occurring on the luminal surfaces may not represent characteristics of the microvilli occurring on the intercellular surfaces and on the basal cell surfaces adjacent to the BM, and that occurrence of the microvilli on the epithelial cell surfaces may reflect a higher metabolic activity of proliferative epithelial cells and may play an important role in the processes of tumor growth during bladder carcinogenesis.     

An ultrastructural study of a juvenile melanoma.

An unusual variant of juvenile melanoma, namely a sclerosing juvenile melanoma occurring on the buttock, has been studied by light and electron microscopy. The diagnosis of a pigment tumour was confirmed by the presence of structures common to these lesions, i.e. melanosomes, intracytoplasmic fibrils and microvilli on the cell surface. The tumour consisted of two cell configurations, namely a multinucleated giant cell and a second cell made up of two separate cells lying in close apposition, the cytoplasm of one cell being dark and the other light. This tumour can be differentiated from a benign naevus by the bizarre histological appearance on light microscopy. On electron microscopy the distinction is made by the presence of the very large multinucleated giant cells, the apposition of the light and dark cells, the scanty melanosomes and the presence of intracytoplasmic lumina. The value of electron microscopy in the determination of the nature of unusual skin tumours is discussed.     

Epithelial surfaces of the trachea and principal bronchi in the rat.

The epithelial surfaces in the trachea and principal bronchi of healthy rats were examined by scanning electron microscopy. A system of four cell types, ciliated, microvillous, brush, and goblet cells, in this order of frequency, were found and intermediate type cells were not seen. An extensive area of the surface examined was covered by densely ciliated epithelium. The presence of other cell types beneath the cilia was confirmed by transmission electron microscopy. Areas up to 1 mm in diameter and randomly distributed were observed where microvillous cells predominated and only occasional ciliated cells were found. Most ciliated cells in these areas were adjacent to glandular openings or goblet cells. The larger microvilli of the brush cells were arranged in a coronal configuration elucidated by the scanning electron microscope. Preparatory techniques recently introduced for the examination of soft tissue in the scanning electron microscope facilitated the confirmation of cell types present and the microarchitecture of the epithelial surface.