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Cyst Wall (cyst + wall)
Selected AbstractsStereotactic biopsy and cytological diagnosis of solid and cystic intracranial lesionsCYTOPATHOLOGY, Issue 3 2003L. M. Collaço Cytological smears from 115 consecutive cases of stereotactic biopsies of intracranial lesions were reviewed. Ninety-five lesions were solid and 20 cystic. Material from 90 solid and 13 cystic lesions was sent both for cytological and histological examination. In 66 of the solid lesions, the cytological diagnosis was confirmed by histology (five were benign lesions and 61 malignant tumours: 56 primary brain tumours, three metastases and two lymphomas). In 24 cases with discrepant cytology and histology, the histology was inconclusive or insufficient in 14 cases, while cytology established the diagnosis of astrocytoma grade II (seven cases), metastases (two cases), gliosis (one case) and benign (four cases). Necrosis of tumour type was observed cytologically in six patients representing glioblastoma (two cases), anaplastic astrocytoma (one case), lymphoma (one case) and normal brain (two cases) histologically. Three cases reported cytologically as benign were primary brain tumour (two cases) and gliosis (one case). One smear of a glioblastoma was insufficient for cytological diagnosis. Cystic lesions were cytologically benign in 17 cases and malignant in three cases. Histology from the cyst wall confirmed the malignant diagnosis in three cases and showed tumour in six more cases, a benign process (two cases), changes induced by radiotherapy for arteriovenous malformation (one case) and insufficient material (one case). In conclusion, cytology from solid brain lesion allows an accurate diagnosis and subtyping of tumours in a majority of cases, and can thus be used to choose type of therapy. In cystic brain tumours, however, examination of the cystic fluid, is often inconclusive and a biopsy from the cyst wall should be performed if there is clinical or radiological suspicion of tumour. [source] Intraoral Extraction of Cheek Skin CystDERMATOLOGIC SURGERY, Issue 12 2005Richard Bennett MD Background. When a physician encounters a benign subcutaneous cyst in the cheek, his or her decision whether to excise and how to excise the cyst takes into account the potential risk of postsurgical scarring. Objective. To describe and show an intraoral buccal mucosal approach to excising a cyst in the inferior-anterior cheek so that skin scarring is avoided. Method. An incision was made intraorally in the buccal mucosa, and dissection was carried through the buccinator muscle until the cyst wall was seen. Careful separation of tissue around the cyst was done by blunt dissection, and the unruptured cyst was removed through the buccal mucosal incision. Result. The entire intact cyst was removed without creating any excision marks in the cheek skin. No complications were encountered, and buccal mucosal healing was excellent. Conclusion. A buccal mucosal intraoral approach is an alternative to a percutaneous excision to remove a cyst in the lower cheek region. The intraoral approach avoids a visible scar on the cheek skin. RICHARD BENNETT, MD, MUBA TAHER, MD, AND JUSTINE YUN, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Retroperitoneal perforation of a pancreatic cyst during endoscopic retrograde pancreatographyDIGESTIVE ENDOSCOPY, Issue 2 2003TOMOYUKI KAWAKITA A 70-year-old man was admitted to Ueno Municipal Hospital, Ueno, Japan, for evaluation of abdominal distension. Computed tomography showed a 1 × 1 cm cyst at the pancreas tail. Endoscopic retrograde pancreatography (ERP) showed a normal pancreatic duct after the first gentle injection and an enhanced cyst at the pancreas tail. Extravasation of the contrast medium occurred from the pancreatic duct to the superior-dorsal extrapancreas at the same time of the next low-pressure manual injection. Computed tomography showed extravasation of the contrast medium from the pancreas cyst to the retroperitoneal space after ERP. It was considered that the cyst wall weakness, in addition to slight elevated pancreatic duct pressure, caused the disruption of the cyst wall. [source] Multiple eccrine hidrocystomas of the faceINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2001Abdullah Alfadley MD, FRCP(C) Background Multiple eccrine hidrocystomas of the face are a rare facial dermatosis for which no recent large series of cases has been reported. Objective To describe the clinicopathologic features of five cases of multiple eccrine hidrocystoma and to emphasize their similar characteristics. Methods The clinical and histologic features of five women with multiple eccrine hidrocystomas of the face are described. Results All cases were middle-aged women with numerous, asymptomatic, skin-colored to bluish, papulonodular skin lesions, ranging from 2 to 5 mm in diameter, and mainly centrifacial in distribution. Histopathologically, all cases showed unilocular cysts in the dermis lined by two layers of cuboidal cells. Staining for S-100 protein was negative in the cyst wall in all cases. One case was treated with topical 1% atropine for 3 weeks with no significant improvement. No systemic side-effects were observed during this treatment. Conclusions Multiple eccrine hidrocystomas are a rare condition which might be confused clinically and histopathologically with apocrine hidrocystomas. To date, no effective treatment has been reported. [source] Simultaneous occurrence of sublingual dermoid cyst and oral alimentary tract cyst in an infant: a case report and review of the literatureINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 6 2003M. W. S. Ho Summary. The simultaneous occurrence of sublingual dermoid cyst and oral alimentary tract cyst is very rare. A literature search revealed only two previous cases [1,2] and one other, where a dermoid cyst was associated with a gastrointestinal microcyst in its cyst wall [3]. We report a case of a six-week-old Caucasian boy, who presented with swelling of the tongue and floor of mouth, which interfered with his normal feeding and swallowing. The swelling was rapidly increasing in size and had become an airway threat. Magnetic resonance imaging (MRI) scans revealed the presence of a lobulated lesion arising in the region of the floor of the mouth on the left and a further lobule which actually invaded the soft tissues of the inferior aspect of the tongue. These two cystic lesions were excised surgically via an intraoral approach and the infant made a complete recovery postoperatively, with resumption of normal feeding and swallowing. The differential diagnoses and approach to sublingual swellings are discussed and the importance of prompt treatment is emphasized. [source] Erythropoietin-producing renal cell carcinoma in chronic hemodialysis patients: A report of two casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2003SHINICHI SAKAMOTO Abstract Erythropoietin (EPO)-producing renal cell carcinomas in two hemodialysis patients are reported. Despite deteriorated kidney function, these patients did not manifest anemia at diagnosis and their elevated serum EPO levels rapidly returned to within the normal range after nephrectomy. Immunohistochemical staining of the resected specimens showed production of erythropoietin in the tumor cells in one case and in the lining cells of the cyst wall in the other case. Renal cell carcinoma could cause an increase of blood hematocrit level in dialysis patients. [source] Resistance, biguanide sorption and biguanide-induced pentose leakage during encystment of Acanthamoeba castellaniiJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2004N.A. Turner Abstract Aims:, This study investigates the effects of biguanides during encystment of Acanthamoeba castellanii. Methods and Results:, A non-nutrient encystment system was used to investigate the changes in the levels of sorption (uptake) of three non-cysticidal concentrations (10, 20 and 50 ,g ml,1) of chlorhexidine diacetate (CHA) and polyhexamethylene biguanide (PHMB) as well as their effects on viability and leakage of pentose sugars during the first 36 h of encystment. Trophozoites treated with CHA or PHMB were more sensitive and generally sorbed more of each biocide than cysts. During encystment, the largest increases in resistance developed between 18 and 36 h for both biguanides with the resistance emerging to biguanide concentrations of 10 or 20 ,g ml,1 between 18 and 24 h. At 50 ,g ml,1 resistance emerged between 24 and 36 h. There was a general decrease in biocide sorption during encystment between 0,24 and 0,21 h for CHA and PHMB, respectively, at a concentration of 50 ,g ml,1. The greatest decline in biguanide-induced pentose leakage was between 0 and 12 h. Conclusions:, The results suggest that during encystment some of the changes in the susceptibility to CHA or PHMB may be related to decreases in the levels of biocide sorption, which is limited by the developing cyst wall. Significance and Impact of the Study:, During encystation, changes occur in biguanide sensitivity. The physical barrier of the cyst wall may be an important factor in limiting biocide sorption. [source] Ultrasonographic assessment of Baker's cysts after intra-articular corticosteroid injection in knee osteoarthritisJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2006J. Carlos Acebes MD Abstract Purpose: To assess sonographic changes in Baker's cysts (BCs) of patients with knee osteoarthritis after a single intra-articular corticosteroid injection. Methods: Thirty patients with knee osteoarthritis complicated with a symptomatic BC received a single intra-articular injection of 40 mg triamcinolone acetonide. Knee pain, swelling, and range of motion were evaluated. BC area and thickness of the cyst wall were measured with sonography before and 4 weeks after local treatment. Results: A significant improvement in knee pain, swelling, and range of motion after corticosteroid injection was accompanied by a decrease in size of the BCs as well as in thickness of the cyst wall as measured by sonography. Moreover, the reduction of BC area on sagittal scans after treatment was significantly correlated with the improvement in range of motion. Conclusions: In this series of osteoarthritis patients, injection of corticosteroids inside the knee joint accounted for a reduction in BC dimensions as well as cyst wall thickness. Sonography can be used not only for the diagnosis of BCs but also to monitor response to therapy. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:113,117, 2006 [source] Giant clear cell hidradenoma of the kneeJOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2010Gengsheng Yu Hidradenomas, also referred to as nodular hidradenomas or clear cell hidradenomas (CCH), are benign cutaneous eccrine tumors usually 2,3 cm in dimension. Hidradenomas are relatively common; however, giant forms are rare. We report a case of an 8.0 × 6.0 × 3.0 cm clear cell hidradenoma of the left knee in a 43-year-old man. The tumor was mobile, located above the patellar tendon and was without bony involvement on imaging studies. Grossly, the resected tumor was unencapsulated and tan, with a solid and cystic cut surface showing papillary excrescences on the cyst wall. Microscopically, the tumor cells showed an infiltrative growth pattern at the periphery, however, the tumor cytology was bland and no necrosis or mitoses were identified. The overlying dermis contained hemosiderin pigment deposition and infiltration with eosinophils. Immunohistochemically, tumor cells were positive for cytokeratin, CAM5.2, p53, carcino-embryonic antigen (CEA) and epithelial membrane antigen (EMA), and negative for CD10 and Ki-67. The cytological features of hidradenomas can present diagnostic challenges, as other ,clear cell' tumors such as metastatic renal cell carcinoma should be considered. Immunohistochemical studies and differential diagnoses are discussed. Yu G, Goodloe S, D'Angelis CA, McGrath BE, Chen F. Giant clear cell hidradenoma of the knee. [source] A histopathological and lectin-histochemical study of the lining epithelium in postoperative maxillary cystsORAL DISEASES, Issue 5 2002M Maruyama OBJECTIVE:,Histopathological and lectin-histochemical characteristics were studied in the lining epithelium of postoperative maxillary cysts (POMC). MATERIALS AND METHODS:,Histological (HE, PAS, AB), immunohistochemical (CD3 and L26) and lectin (wheat germ agglutinin, WGA; Ulex europaeus agglutinin I, UEA-I; concanavalin A, ConA) stainings were performed in the 360 POMC specimens. The number of goblet cells and inflammatory cells was counted and statistically analyzed. RESULTS:,The lining epithelium was classified into three types based on histopathological characteristics; pseudostratified ciliated epithelium (pSCE), transitional epithelium (TE) and stratified squamous epithelium (SSE). Local infiltration of inflammatory cells into the cyst wall was associated with an increased number of goblet cells in the lining epithelium. The observed association between the infiltration of inflammatory cells and an increase in the number of goblet cells was statistically significant in groups with lining pSCE and TE. Glycoconjugate histochemical analysis revealed that the surfaces of the lining epithelium with squamous metaplasia showed an increased degree of staining reactivity with UEA-I, whereas the staining reactivity with ConA was reduced. Goblet cells were able to be stained with WGA and UEA-I, but showed extremely low reactivity with ConA. CONCLUSION:,Changes in the glycoconjugate expression of the metaplastic lining epithelium and goblet cell development play an important role in the local defense mechanisms against inflammatory factors in POMC. [source] Eosinophil cationic protein damages protoscoleces in vitro and is present in the hydatid cystPARASITE IMMUNOLOGY, Issue 8 2006A. L. RAMOS SUMMARY Eosinophils are locally recruited during the establishment and chronic phases of cystic hydatidosis. This study provides evidence that eosinophil cationic protein (ECP), one of the major components of eosinophil granules, can damage Echinococcus granulosus protoscoleces (PSC). The toxicity of ECP was investigated in vitro by following parasite viability in the presence of this protein. ECP was found to damage PSC at micromolar concentrations; the effect was blocked by specific antibodies and heparin, and was more severe than the one caused by similar concentrations of RNase A, suggesting that the cationic nature of ECP, and not its ribonuclease activity, is involved in toxicity. This observation may highlight the capacity of eosinophils to control secondary hydatidosis, derived from PSC leakage from a primary cyst. To further assess the relevance of the previous result during infection, the presence of eosinophil proteins was investigated in human hydatid cysts. ECP was found to be strongly associated with the laminated layer of the cyst wall, and present at micromolar concentrations in the hydatid fluid. Overall, these results demonstrate that eosinophils degranulate in vivo at the host,parasite interface, and that the released ECP reaches concentrations that could be harmful for the parasite. [source] Mucinous cystadenoma of the pancreas with huge mural hematomaPATHOLOGY INTERNATIONAL, Issue 10 2009Takeshi Hisa A 60-year-old woman was referred for evaluation of a cystic mass in the pancreatic body that extended to the tail. Transabdominal ultrasonography demonstrated an oval cystic mass 24 cm in diameter, filled with debris. On the cyst wall there was a wide-based, smooth-surfaced, heterogeneous high-echoic protrusion that was 5 cm in diameter. On CT the protrusion showed internal enhancement. Endoscopic pancreatography showed no intraductal mucin or communication with the cyst. A distal pancreatectomy was performed under the diagnosis of mucinous cystadenocarcinoma. Grossly there was a brownish, hemispherical protrusion into the thin monolocular cyst. The cut surface of the protrusion showed a peripheral yellow-brownish area and an internal wine-colored area. Histopathologically the cyst wall consisted of tall columnar cells without atypical nuclei, ovarian-type stroma beneath the epithelium, and fibrotic tissue with abundant capillary vessels, suggestive of a mucinous cystadenoma. The protrusion was composed of peripheral organized hematoma without a covering epithelium, and internal hemorrhage and many capillary vessels, with no evidence of tumor cell necrosis. These histopathological findings appear to be similar to those of chronic expanding hematoma. The formation of a huge mural hematoma in a mucinous cystic neoplasm can occur as a repair process after the breaking of intrawall vessels. [source] Meningioma in mature cystic teratoma of the ovaryPATHOLOGY INTERNATIONAL, Issue 7 2004Yukio Takeshima A case of meningioma arising in a mature cystic teratoma of the ovary in a 60-year-old woman is described. The tumor was located in the right ovary, and salpingo-oophorectomy was performed. The right ovary was 10 × 10 × 8 cm in size and contained an unilocular cyst. In the wall, a solid nodule measuring 3 × 3 × 2 cm was noted. Histologically, the cyst wall was composed of typical mature cystic teratoma. In contrast, the mural nodule was composed of the proliferating spindle- and polygonal-shaped cells showing positive staining for epithelial membrane antigen and microcystic change was prominent. These findings were consistent with microcystic meningioma. The arachnoidal cells around mature brain tissue may be the origin of this unusual tumor. To the best of our knowledge, this is the first case of mature cystic teratoma with meningioma of the ovary reported in English medical literature. This case may further indicate the totipotential nature of mature cystic teratoma. [source] Ciliated foregut cyst of the gallbladder: A case report and review of the literaturePATHOLOGY INTERNATIONAL, Issue 5 2000Eun Sook Nam A case is presented of a ciliated cyst of the gallbladder in a 36-year-old Korean woman which was incidentally found on ultrasonographic study. A cystic mass measuring 1.5 × 1 × 1 cm was found in the fundus of the gallbladder. The cyst was unilocular and intramural without communication to the lumen. Microscopically, the cyst wall was lined by a single layer of pseudostratified, ciliated, columnar epithelium and goblet cells with underlying smooth muscle layers. This was considered to be the cyst arising from the embryonic foregut and showing differentiation toward respiratory structures. The term ,ciliated foregut cyst of the gallbladder' is suggested here. [source] Some observations of the structure of the choroid plexus and its cystsPRENATAL DIAGNOSIS, Issue 13 2002Ivan Kraus Abstract The structure of the choroid plexus was studied in five normal human embryos, three normal fetuses and three fetuses with choroid plexus cysts. These were detected by ultrasound and the fetuses were karyotypically normal. The choroid plexus appears in the lateral cerebral ventricles at the seventh developmental week. The early structure is lobulated with vessels running in the mesenchymal stroma and forming capillary nets under the single-layered ependymal epithelium. This embryonal structure is converted into the fetal type during the ninth developmental week as the embryonal capillary net is replaced by elongated loops of wavy capillaries that lie under regular longitudinal epithelial folds. The choroid plexus cysts exhibited accumulation of fluid within distended mesenchymal stroma and did not show the wavy folds on this surface, which was smooth. Within this connective tissue of the cyst wall were distended angiomatous interconnecting thin-walled capillaries. Therefore, filled cavities were not lined by any epithelium. We suggest that fetal choroid plexuses cysts (at least in many cases) are in fact pseudocysts exhibiting angiomatous patterns of capillaries in their walls. Copyright © 2002 John Wiley & Sons, Ltd. [source] Case of cystic schwannomaTHE JOURNAL OF DERMATOLOGY, Issue 11 2008Yu Sung CHOI ABSTRACT Schwannoma is a well-defined tumor arising from the nerve sheath. It may present as a solitary mass in any part of the body, but is more commonly seen in the head, neck and extremities. We describe a 32-year-old female patient with a small dermal nodule on the forehead, which was 2 cm in diameter, round and of a cystic nature. Microscopic examination revealed that it consisted of compact spindle cells arranged partly in short bundles or a fascicular pattern with outstanding cystic degeneration manifested as a large, unilocular cavity in the center of the tumor tissue. The tumor cells were positive for S-100 protein and negative for epithelial membrane antigen (EMA), while the tumor capsule was positive for EMA. There was no S-100-positive membrane-like structure lining the cyst wall. [source] Morphological and Molecular Characterization of a New Protist Family, Sandmanniellidae n. fam. (Ciliophora, Colpodea), with Description of Sandmanniella terricola n. g., n. sp. from the Chobe Floodplain in BotswanaTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2009WILHELM FOISSNER ABSTRACT. Sandmanniella terricola n. g., n. sp. was discovered in soil from the Chobe floodplain, Botswana, southern Africa. Its morphology and 18S rDNA gene sequence were studied with standard methods. Sandmanniella terricola is very likely an adversity strategist because it reaches peak abundances 6,12 h after rewetting the soil and maintains trophic food vacuoles with undigested bacteria in the resting cyst, a highly specific feature suggested as an indicator for an adversity life strategy. Possibly, the energy of the stored food vacuoles is used for reproduction and support of the cyst wall. Morphologically, Sandmanniella terricola is inconspicuous, having a size of only 50 × 40 ,m and a simple, ellipsoidal shape. The main characteristics of the genus are a colpodid silverline pattern; a perioral cilia condensation; a flat, dish-shaped oral cavity, in the centre of which originates a long, conical oral basket resembling that of certain nassulid ciliates; and a vertically oriented left oral polykinetid composed of brick-shaped adoral organelles. This unique mixture of features and the gene sequence trees, where Sandmanniella shows an isolated position, suggest establishing a new family, the Sandmanniellidae n. fam., possibly related to the families Colpodidae or Bryophryidae. The curious oral basket provides some support for the hypothesis of a common ancestor of colpodid and nassulid ciliates. [source] Descriptions of Protospathidium serpens (Kahl, 1930) and P. fraterculum n. sp. (Ciliophora, Haptoria), Two Species Based on Different Resting Cyst MorphologyTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 4 2005KUIDONG XU Abstract. Protospathidium serpens (Kahl, 1930) is frequent in semiterrestrial and terrestrial habitats worldwide. Conventionally, all populations are considered as conspecific because they have very similar overall morphologies and morphometrics. We studied in detail not only the morphology of the vegetative cells but also the resting cysts using live observation, protargol impregnation, and scanning electron microscopy. These revealed a cryptic diversity and biogeographic pattern in details of the dorsal brush and cyst wall morphology. The cyst wall is spiny in the Austrian specimens, while smooth in the South African and Antarctic populations. Accordingly, P. serpens consists of at least two species: P. serpens (with spiny cyst wall) and P. fraterculum n. sp. (with smooth cyst wall); the latter is probably composed of two distinct taxa differing by the absence (South African)/presence (Antarctic) of a monokinetidal bristle tail in brush row 3, the number of dikinetids comprising brush row 1 (seven versus three), and the total number of brush dikinetids (29 versus 17). Protospathidium serpens is neotypified with the new population from Austria. The significance of resting cyst morphology is discussed with respect to alpha-taxonomy and overall ciliate diversity. [source] Ultrastructural Study of Encystation and Excystation in Acanthamoeba castellaniiTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2 2005BIBIANA CHÁVEZ-MUNGUÍA Abstract. Encystation and excystation of Acanthamoeba castellanii were studied by transmission electron microscopy. The differentiation process was induced in asynchronous cultures grown axenically. Cytoplasmic vesicles containing a dense fibrous material very similar in appearance to the cyst wall were observed in trophozoites induced to encyst. When these trophozoites were incubated with calcofluor white m2r, fluorescence was observed in cytoplasmic vesicles, suggesting that the material contained in these vesicles corresponded to cyst wall precursors. Semithin cryosections of mature cysts with the same treatment showed fluorescence in the ectocyst and a less intense fluorescence in the endocyst, suggesting the presence of cellulose in both structures of the cyst wall. In mature cysts induced to excystation, small structures very similar to electron-dense granules (EDG) previously described in other amoebae were frequently observed. The EDGs were either sparsely distributed in the cytoplasm or associated with the cytoplasmic face of the plasma membrane. Many of them were located near the ostiole. In advanced phases of excystation, endocytic activity was suggested by the formation of endocytic structures and the presence of vacuoles with fibrous content similar to that of the cyst wall. Electron-dense granules in the process of dissolution were also observed in these vacuoles. Furthermore, the formation of a pseudopod suggests a displacement of the amoeba toward the ostiole. [source] Ultrastructure, Eneystment and Cyst Wall Composition of the Resting Cyst of the Peritrich Ciliate Opisthonecta henneguyiTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 1 2003PURIFICACIÓN CALVO ABSTRACT. The cyst wall of Opisthonecta henneguyi has been studied ultrastructurally and cytochemically by light and electron microscopy, as well as by chemical and electrophoretic analyses, to examine the structure of the cyst wall and its composition. The cyst wall consists of four morphologically distinct layers. The ectocyst is a thin dense layer. The mesocyst is the thickest layer and is composed of a compact material. The endocyst is a thin layer like the ectocyst, but less dense. The granular layer varies in thickness and is composed of a granular material. In the resting cyst, kinetosomes of both oral apparatus and trochal band as well as the myoneme system are maintained, and only cilia are resorbed. The sugars present in the cyst wall are predominantly N-acetylglucosamine (90%) and glucose (10%). The niesocyst is composed of chitin, and the endocyst includes glycoproteins and acid mucopolysaccharides. During secretion of the cyst wall, the endocyst and granular layer are secreted from precursors synthesized "de novo". No cytoplasmic precursors of ectocyst and mesocyst have been detected. [source] Cyst Formation in a Freshwater Strain of the Choanoflagellate Desmarella moniliformis KentTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2000BARRY S. C. LEADBEATER ABSTRACT. Cyst formation in a freshwater strain of the colonial freshwater Choanoflagellate Desmarella moniliformis Kent (Protozoa; Choanoflagellida) has been studied with light and electron microscopy for the first time. Batch cultures inoculated with motile vegetative cells start to produce cysts within 3 days during the exponential phase of growth. Cyst production proceeds until in late stationary phase there is a preponderance of cysts. Transfer of cysts to fresh medium results in limited excystment. Encystment involves the production of electron-dense fibrillar wall material, firstly around the neck of the cell and then around the posterior end. As the wall material is deposited the neck of the cell elongates and the dictyosome rotates from the horizontal to vertical plane. The number of mitochondrial profiles seen in individual sections of cells increases. Finally the neck of the cell is retracted, the flagellum and collar tentacles are withdrawn, and the bottom of the neck of the cyst wall is sealed with a diaphragm of wall material. Excystment, which has not been observed directly, appears to involve the disruption of the wall at the base of the neck, the remainder of the cyst wall remains intact. Comparisons are made between encystment in Desmarella and cyst development in other protists. [source] Screening of an Echinococcus granulosus cDNA library with IgG4 from patients with cystic echinococcosis identifies a new tegumental protein involved in the immune escapeCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2005E. Ortona Summary The worldwide problem of chronic Echinococcus granulosus disease calls for new parasite-derived immunomodulatory molecules. By screening an E. granulosus cDNA library with IgG4 from patients with active cystic echinococcosis, we identified a cDNA that encodes a predicted partial protein that immunofluorescence studies localized in the protoscolex tegument and on the germinal layer of cyst wall. We named this protein EgTeg because the 105 amino acid sequence scored highest against a family of Schistosoma tegumental proteins. Evaluating the role of EgTeg in the human early inflammatory response we found that EgTeg significantly inhibited polymorphonuclear cell (PMN) chemotaxis. Cytometric analysis of intracellular cytokines disclosed a significantly higher percentage of cells producing IL-4 than IFN-, (P = 0·001, Student's t-test) in T lymphocytes from patients with cystic echinococcosis stimulated with EgTeg. EgTeg induced weak Th1-dependent proliferation in 42% of patients' peripheral blood mononuclear cells. In immunoblotting (IB) analysis of total IgG and IgG subclass responses to EgTeg in patients with cystic echinococcosis, patients with other parasitoses, patients with cystic lesions and healthy controls, total IgG specific to EgTeg yielded high sensitivity (73%) but low specificity (44%) precluding its use in immunodiagnosis. Conversely, IgG4 specific to EgTeg gave acceptable sensitivity (65%) and high specificity (89%) suggesting its use in immunodiagnosis to confirm ultrasound documented cysts suggestive of E. granulosus. Because the new tegumental antigen EgTeg inhibits chemotaxis, induces IL-4-positive T lymphocytes and noncomplement fixing antibodies (IgG4) it is an immunomodulatory molecule associated with chronic infection. [source] Carcinomas arising in multilocular thymic cysts of the neck: a clinicopathological study of three casesHISTOPATHOLOGY, Issue 1 2004C A Moran Aims :,To report three cases of primary carcinoma of the neck arising in multilocular thymic cysts (MTC). Methods and results :,The patients were three men aged 47, 50 and 52 years who presented with a painless neck mass of several weeks' duration. The patients had no history of previous surgical procedures or of malignancy elsewhere. The tumours in all three patients were located on the right lateral side of the neck; all patients underwent complete surgical resection of the mass. Grossly, the tumours were cystic and measured between 20 and 30 mm in greatest diameter. Histologically, the tumours showed cyst walls lined by squamous epithelium. The cyst walls contained prominent germinal centres with lymphoid hyperplasia, cholesterol cleft granulomas, and scattered keratinized structures reminiscent of Hassall's corpuscles. In addition, a neoplastic cellular proliferation composed of round to oval cells arranged in sheets and originating from the lining of the cystic structures was present. The neoplastic cells showed moderate amounts of eosinophilic cytoplasm, round nuclei, and, in some areas, prominent nucleoli. Mitotic figures were easily found, and cellular pleomorphism was present in several areas. In two cases the tumours showed features of basaloid carcinoma of the thymus, while in one case the pattern was that of squamous cell carcinoma. Immunohistochemical studies for keratin showed a strong positive reaction in the tumour cells, while leucocyte common antigen strongly stained the lymphoid background. Follow-up information obtained in two patients showed them to be alive 6 months after initial diagnosis. One patient was lost to follow-up. Conclusion :,The cases described here represent an unusual variant of carcinoma arising in multilocular thymic cyst in the neck region. [source] Apparent wall thickening of cystic renal lesions on MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Vikas Gulani MD Abstract Purpose To show that cystic renal lesions that would otherwise meet criteria for simple cysts can demonstrate perceptible walls or increased wall thickness on MRI, sometimes causing these lesions to be "upgraded." It was hypothesized that thickening of cyst walls on MRI can be artifactual, due to data truncation, applied filtering, and low signal-to-noise ratio (SNR). Materials and Methods k-Space data for a 4-cm cyst were created in a 40-cm field of view (FOV) (512 × 512 matrix). Additional data sets were created using the central 512 × 256 and 512 × 128 points. Noise was simulated so that the cyst SNR was approximately 7, 14, and 20, respectively. Actual wall thickness was set at 0.25 mm, and cyst:wall signal at 1:4. An inverse two-dimensional (2D) fast Fourier transform (FFT) yielded simulated images. A Fermi filter was applied to reduce ringing. Images/projections were examined for wall thickening. Seven patients with initially thick-walled cysts on fat-saturated spoiled gradient-echo (FS-SPGR) images were scanned with increasing resolution (256 × 128 and 256 × 256; four patients were also scanned with 512 × 512). Average wall thickness at each resolution was compared using a two-tailed paired Student's t -test. Results Simulations showed apparent wall thickening at low resolution, improving with higher resolutions. Low SNR and application of the Fermi filter made it difficult to identify ringing as the cause of this thickening. The simulation results were confirmed on seven patients, whose cyst walls proved to be artifactually thickened (P < 0.01). Conclusion Thickening of cyst walls on MRI can be artifactual. Upon encountering thick-walled cystic renal lesions, high-resolution images can be acquired to exclude apparent thickening. J. Magn. Reson. Imaging 2008;28103,110. © 2008 Wiley-Liss, Inc. [source] Histopathological and immunohistochemical analysis of calcifying odontogenic cystsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2001Mitsuhide Yoshida Abstract: Method and Results: Calcifying odontogenic cysts (COCs) were examined histopathologically and immunohistochemically to characterize the histological and cytological properties of these lesions. Histopathologically, COCs showed thin or thick lining epithelium with ghost cells. COCs were classified according to proliferative type or nonproliferative type lining epithelium, the presence or absence of ameloblastomatous appearance, and the presence or absence of odontoma in the cyst walls. Immunohistochemically, amelogenin protein was expressed chiefly in ghost cells, whereas cytokeratin 19 (CK19) and bcl-2 proteins were expressed chiefly in lining epithelial cells. The proportion of cases positive for bcl-2 protein was slightly higher in COCs with odontoma than in those without odontoma. Lining epithelial cells sporadically showed positive reactions for Ki-67 antigen. Mean Ki-67 labeling index was slightly greater in COCs with proliferative type lining epithelium, COCs with ameloblastomatous appearance of the cyst walls, and COCs with odontoma of the cyst walls than in COCs without these histological features. Our results suggest that ghost cells or lining epithelial cells show ameloblastic cytodifferentiation or odontogenic epithelial characteristics, that bcl-2 protein is associated with survival of lining epithelial cells in COCs, and that high proliferation potential is associated with ameloblastomatous proliferation or combined odontoma. COCs exhibited various histological features with several transitional forms, and immunohistochemical examinations revealed little or no difference in cytodifferentiation and cellular activity among COCs. Conclusion: We conclude that COCs with various histological features have neoplastic potential and may not be separate entities within the same histological spectrum. [source] Benign cysts in the central nervous system: Neuropathological observations of the cyst wallsNEUROPATHOLOGY, Issue 1 2004Asao Hirano A diverse variety of benign cysts exist in the CNS. Advances in diagnostic radiology have facilitated diagnoses and surgical intervention in many patients with CNS cysts. However, a fundamental understanding of the pathological features of these lesions is clinically vital. From an etiological point of view, the cysts can be divided into two groups. The first includes lesions that arise from within the CNS and may be static structures such as cavities arising from infarcts and other destructive processes while other lesions such as arachnoid cysts, ependymal cysts, cystic hemangioblastoma, cystic cerebellar astrocytoma and infectious processes, are progressive. The second group of cysts arise from the intrusion of non-nervous system tissue into the neuroaxis and are usually midline. They are frequently expanding congenital lesions although some become symptomatic only in adults. Examples include teratomas, dermoid cysts, epidermoid cysts, craniopharyngiomas, Rathke's cleft cysts, and other epithelial cysts presumably derived from the upper respiratory or intestinal tract. Chick embryos exposed to lead have been used as a model of cyst formation. [source] Epithelioid sarcoma presenting as pulmonary cysts with cancer antigen 125 expressionRESPIROLOGY, Issue 6 2006Eiki KIKUCHI Abstract: A 39-year-old Japanese woman presented with a swollen right hand and a right-sided pneumothorax. Chest CT revealed bilateral multiple pulmonary thin-walled cysts measuring ,1 cm in diameter and small nodules. An initial skin biopsy led to a misdiagnosis of metastatic adenocarcinoma, as tumour cells were positive for cytokeratin, epithelial membrane antigen, carcinoembryonic antigen and cancer antigen 125. However, chemotherapy proved ineffective, and the skin biopsy was repeated. A final diagnosis of epithelioid sarcoma (ES) was made. Open lung biopsy showed that the pulmonary nodules represented metastases of ES. Although the pulmonary cyst walls did not contain tumour cells, bronchiolar wall adjacent to the cysts had been infiltrated by tumour cells. These findings suggested that pulmonary cysts, a rare form of pulmonary metastases from soft tissue sarcomas, had developed through a ball-valve effect of metastatic tumour in small airways. However, presence of cancer antigen 125 hindered obtaining a correct diagnosis of ES. [source] Recurrent ,sterile' verrucous cyst abscesses and epidermodysplasia verruciformis-like eruption associated with idiopathic CD4 lymphopeniaBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2003E. Tobin Summary Rupture of follicular (epidermoid) cysts is believed to be the consequence of bacterial infection. We report a 24-year-old man with idiopathic CD4 lymphopenia and chronic Mycobacterium avium intracellulare infection who developed multiple, recurring painful abscesses over the distal extremities that increased in number and severity when systemic steroid and interferon-, treatment was instituted for interstitial lung disease. Cultures were consistently negative for microorganisms, but pathological examination revealed ruptured epidermoid cyst walls with human papillomavirus (HPV) viropathic changes (keratinocytes with perinuclear halos and abundant basophilic keratohyaline granules). Cutaneous examination showed numerous, widespread flat-topped papules and achromic macules over the extremities, head and neck. Nested polymerase chain reaction analysis for HPV DNA revealed that the abscess-related cyst walls harboured epidermodysplasia verruciformis (EV)-associated HPV types 20, 24, alb-7 (AY013872) and 80. His cutaneous lesions harboured HPV types 3, 8 and 80. Similar to past reports, our patient developed an EV-like eruption in the setting of immunodeficiency. In this instance, EV-associated HPV infection of the follicular infundibular epithelium or pre-existing cysts in the setting of immunodeficiency may have led to cystic growth, rupture and subsequent painful inflammation. [source] | |||||||||||||||||||||||||||||||