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Cyst Morphology (cyst + morphology)
Selected AbstractsCYST,THECA RELATIONSHIP, LIFE CYCLE, AND EFFECTS OF TEMPERATURE AND SALINITY ON THE CYST MORPHOLOGY OF GONYAULAX BALTICA SP.JOURNAL OF PHYCOLOGY, Issue 4 2002NOV. (DINOPHYCEAE) FROM THE BALTIC SEA AREA A new species of Gonyaulax, here named Gonyaulax baltica sp. nov., has been isolated from sediment samples from the southeastern Baltic. Culture strains were established from individually isolated cysts, and cyst formation was induced in a nitrogen-depleted medium. Although G. baltica cysts are similar to some forms attributed to Spiniferites bulloideus and the motile stage of G. baltica has affinities with G. spinifera, the combination of features of cyst and motile stage of G. baltica is unique. The culture strains were able to grow at salinity levels from 5 to 55 psu and formed cysts from 10 to 50 psu. Cultures at each salinity level were grown at 12, 16, and 20° C. Temperature- and salinity-controlled morphological variability was found in the resting cysts. Central body size varied with temperature and salinity, and process length varied with salinity. Cysts that formed at extreme salinity levels displayed lower average process length than cysts formed at intermediate salinity levels, and central body length and width were lowest at higher temperature and lower salinity. Models for the relationship between central body size and temperature/salinity and process length and salinity have been developed and may be used to determine relative paleosalinity and paleotemperature levels. Our results on salinity-dependent process length confirm earlier reports on short-spined cysts of this species found in low salinity environments, and the model makes it possible to attempt to quantify past salinity levels. [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] Highly symptomatic adult polycystic liver disease: options and results of surgical managementANZ JOURNAL OF SURGERY, Issue 8 2004Yu Meng Tan Background: The majority of patients afflicted with adult polycystic liver disease (APLD) are asymptomatic. For those who are symptomatic, there are a variety of treatment procedures that have been proposed but these lack verification through long-term studies with respect to safety and long-term effectiveness. Choice of surgical procedure is related to the severity of APLD and morphology of the cysts within the liver. The aim of the present study was to analyse the immediate and long-term results of fenestration and combined resection,fenestration at Singapore General Hospital. Methods: A retrospective analysis of clinical, operative, imaging and follow-up data was carried out for 12 patients (10 women and two men) with symptomatic APLD who underwent surgery from January 1992 to December 2000. The primary outcome measures assessed were postoperative alleviation of symptoms, performance status, complications, mortality and long-term recurrence of symptoms. Results: Nine patients underwent 12 fenestration procedures and three patients had combined resection,fenestration. Fenestration was carried out for eight of nine patients with a dominant cyst morphology and combination resection,fenestration was carried out for those three patients with diffuse cyst morphology. There was no operative mortality and all patients were discharged from hospital free of their preoperative symptoms. Overall morbidity rate was 58%. The mean follow up for the present cohort was 29.3 months. Only two patients had recurrence of symptoms. One patient with dominant cyst morphology who underwent laparoscopic fenestration had recurrence at 26 and 43 months but this was successfully treated finally with open fenestration. The other patient had diffuse cyst morphology and was treated with fenestration for recurrent cyst infection that recurred 1 month postoperatively. This required subsequent intravenous antibiotics and percutaneous drainage for resolution of symptoms. Conclusion: Treatment for symptomatic APLD should be based on the morphology of the liver cysts. Fenestration is a safe and acceptable procedure for patients with a dominant cyst pattern where liver size can be reduced after the cysts collapse. A combination of resection,fenestration is suitable for those with a diffuse cyst pattern where grossly affected segments are resected in combination with fenestration to allow for reduction in liver size. [source] | ||||||||||