979 resultados para Chrysophyceae cysts
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Intraosseous ganglia of the distal tibia are rare. We evaluated the feasibility of surgically treating these lesions with an arthroscopically assisted technique. Five patients with symptomatic distal tibial ganglia underwent surgical curettage and excision with this technique. All patients underwent débridement of the chondral lesion and hypertrophied synovial lining when present, probing of the portal to the ganglion, and subsequently thorough curettage with bone grafting performed through a cortical window made from a separate small incision. Biopsy confirmed the diagnosis in all patients. All patients had eventual relief of symptoms with good integration of bone graft at final followup. There were no recurrences at a minimum followup of 19 months (mean, 38.6 months; range, 19-69 months). Mean time for return to full function was 15.4 weeks (range, 8-17 weeks). There were no intraoperative or postoperative complications. The mean American Orthopaedic Foot and Ankle Society scores increased from 73 points (range, 67-77 points) preoperatively to 94 points (range, 90-100 points) postoperatively. Arthroscopically assisted surgical treatment of ganglia of the distal tibia in the appropriate patient is a reasonably simple technique that relieves symptoms and helps the patient to regain normal gait and full function with no recurrence (in our small series). LEVEL OF EVIDENCE: Level IV, case series. See Guidelines for Authors for a complete description of levels of evidence.
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Relatively little is known about past cold-season temperature variability in high-Alpine regions because of a lack of natural cold-season temperature proxies as well as under-representation of high-altitude sites in meteorological, early-instrumental and documentary data sources. Recent studies have shown that chrysophyte stomatocysts, or simply cysts (sub-fossil algal remains of Chrysophyceae and Synurophyceae), are among the very few natural proxies that can be used to reconstruct cold-season temperatures. This study presents a quantitative, high-resolution (5-year), cold-season (Oct–May) temperature reconstruction based on sub-fossil chrysophyte stomatocysts in the annually laminated (varved) sediments of high-Alpine Lake Silvaplana, SE Switzerland (1,789 m a.s.l.), since AD 1500. We first explore the method used to translate an ecologically meaningful variable based on a biological proxy into a simple climate variable. A transfer function was applied to reconstruct the ‘date of spring mixing’ from cyst assemblages. Next, statistical regression models were tested to convert the reconstructed ‘dates of spring mixing’ into cold-season surface air temperatures with associated errors. The strengths and weaknesses of this approach are thoroughly tested. One much-debated, basic assumption for reconstructions (‘stationarity’), which states that only the environmental variable of interest has influenced cyst assemblages and the influence of confounding variables is negligible over time, is addressed in detail. Our inferences show that past cold-season air-temperature fluctuations were substantial and larger than those of other temperature reconstructions for Europe and the Alpine region. Interestingly, in this study, recent cold-season temperatures only just exceed those of previous, multi-decadal warm phases since AD 1500. These findings highlight the importance of local studies to assess natural climate variability at high altitudes.
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BACKGROUND: Alveolar echinococcosis (AE) is caused by the larval stage (metacestode) of Echinococcus multilocularis. The domestic dog can act as a definitive host and harbor adult cestodes in its small intestine or become an aberrant intermediate host carrying larval stages that may cause severe lesions in the liver, lungs and other organs with clinical signs similar to AE in humans. CASE PRESENTATION: A case of canine AE, affecting the liver and prostate with development of multilocular hydatid paraprostatic cysts and possible lung involvement is described in an 8-year-old neutered male Labrador retriever dog.The dog presented with progressive weight loss, acute constipation, stranguria and a suspected soft tissue mass in the sublumbar region. Further evaluation included computed tomography of the thorax and abdomen, which revealed cystic changes in the prostate, a paraprostatic cyst, as well as lesions in the liver and lungs. Cytological examination of fine-needle aspirates of the liver, prostate and paraprostatic cyst revealed parasitic hyaline membranes typical of an Echinococcus infection and the presence of E. multilocularis-DNA was confirmed by PCR. The dog was treated with albendazole and debulking surgery was considered in case there was a good response to antiparasitic treatment. Constipation and stranguria resolved completely. Six months after the definitive diagnosis, the dog was euthanized due to treatment-resistant ascites and acute anorexia and lethargy. CONCLUSIONS: To the authors' knowledge, this is the first publication of an E. multilocularis infection in a dog causing prostatic and paraprostatic cysts. Although rare, E. multilocularis infection should be considered as an extended differential diagnosis in dogs presenting with prostatic and paraprostatic disease, especially in areas where E. multilocularis is endemic.
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The objective of this study was to assess the prevalence of renal cysts and other renal abnormalities in purebred Maine Coon cats, and to characterise these through genetic typing. Voluntary pre-breeding screening programmes for polycystic kidney disease (PKD) are offered for this breed throughout Switzerland, Germany and other northern European countries. We performed a retrospective evaluation of Maine Coon screening for renal disease at one institution over an 8-year period. Renal ultrasonography was performed in 187 healthy Maine Coon cats. Renal changes were observed in 27 of these cats. Renal cysts were found in seven cats, and were mostly single and unilateral (6/7, 85.7%), small (mean 3.6 mm) and located at the corticomedullary junction (4/6, 66.7%). Sonographical changes indicating chronic kidney disease (CKD) were observed in 10/187 (5.3%) cats and changes of unknown significance were documented in 11/187 (5.9%) cats. All six cats genetically tested for PKD1 were negative for the mutation, and gene sequencing of these cats did not demonstrate any common genetic sequences. Cystic renal disease occurs with a low prevalence in Maine Coons and is unrelated to the PKD observed in Persians and related breeds. Ultrasonographical findings compatible with CKD are not uncommon in juvenile Maine Coons.
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BRAF inhibitors are broadly used for metastatic melanoma with BRAF mutations. Their use results in various cutaneous side effects, such as the development of keratoacanthomas and squamous cell carcinomas. We report a patient with metastatic melanoma treated with vemurafenib who developed dozens of histologically confirmed epidermal cysts within 2 months after initiation of vemurafenib administration. The cystic lesions were observed only in the localized area where a large exophytic melanoma tumor mass had been previously irradiated. Localized epidermal cysts may constitute an unusual radiation recall reaction in patients treated with BRAF inhibitors.
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Arginine vasopressin (AVP) has a key role in osmoregulation by facilitating water transport in the collecting duct. Recent evidence suggests that AVP may have additional effects on renal function and favor cyst growth in polycystic kidney disease. Whether AVP also affects kidney structure in the general population is unknown. We analyzed the association of copeptin, an established surrogate for AVP, with parameters of renal function and morphology in a multicentric population-based cohort. Participants from families of European ancestry were randomly selected in three Swiss cities. We used linear multilevel regression analysis to explore the association of copeptin with renal function parameters as well as kidney length and the presence of simple renal cysts assessed by ultrasound examination. Copeptin levels were log-transformed. The 529 women and 481 men had median copeptin levels of 3.0 and 5.2 pmol/L, respectively (P<0.001). In multivariable analyses, the copeptin level was associated inversely with eGFR (β=-2.1; 95% confidence interval [95% CI], -3.3 to -0.8; P=0.002) and kidney length (β=-1.2; 95% CI, -1.9 to -0.4; P=0.003) but positively with 24-hour urinary albumin excretion (β=0.11; 95% CI, 0.01 to 0.20; P=0.03) and urine osmolality (β=0.08; 95% CI, 0.05 to 0.10; P<0.001). A positive association was found between the copeptin level and the presence of renal cysts (odds ratio, 1.6; 95% CI, 1.1 to 2.4; P=0.02). These results suggest that AVP has a pleiotropic role in renal function and may favor the development of simple renal cysts.
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In an attempt to document the palaeoecological affinities of individual extant and extinct dinoflagellate cysts, Late Pliocene and Early Pleistocene dinoflagellate cyst assemblages have been compared with geochemical data from the same samples. Mg/Ca ratios of Globigerina bulloides were measured to estimate the spring-summer sea-surface temperatures from four North Atlantic IODP/DSDP sites. Currently, our Pliocene-Pleistocene database contains 204 dinoflagellate cyst samples calibrated to geochemical data. This palaeo-database is compared with modern North Atlantic and global datasets. The focus lies in the quantitative relationship between Mg/Ca-based (i.e. spring-summer) sea-surface temperature (SSTMg/Ca) and dinoflagellate cyst distributions. In general, extant species are shown to have comparable spring-summer SST ranges in the past and today, demonstrating that our new approach is valid for inferring spring-summer SST ranges for extinct species. For example, Habibacysta tectata represents SSTMg/Ca values between 10° and 15°C when it exceeds 30% of the assemblage, and Invertocysta lacrymosa exceeds 15% when SSTMg/Ca values are between 18.6° and 23.5°C. However, comparing Pliocene and Pleistocene SSTMg/Ca values with present day summer values for the extant Impagidinium pallidum suggests a greater tolerance of higher temperatures in the past. This species occupies more than 5% of the assemblage at SSTMg/Ca values of 11.6-17.9°C in the Pliocene and Pleistocene, whereas present day summer SSTs are around -1.7 to 6.9°C. This observation questions the value of Impagidinium pallidum as reliable indicator of cold waters in older deposits, and may explain its bipolar distribution.
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We investigated the influences of temperature, salinity and pH on the calcium isotope as well as trace and minor element (uranium, strontium, magnesium) to Ca ratios on calcium carbonate cysts of the calcareous dinoflagellate species Thoracosphaera heimii grown in laboratory cultures. The natural habitat of this species is the photic zone (preferentially at the chlorophyll maximum depth) of temperate to tropical oceans, and it is abundant in deep-sea sediments over the entire Cenozoic. In our experiments, temperatures ranged from 12 to 30 °C, salinity from 36.5 to 38.8 and pH from 7.9 to 8.4. The delta44/40Ca of T. heimii cysts resembles that of other marine calcifiers, including coccolithophores, foraminifers and corals. However, its temperature sensitivity is considerably smaller and statistically insignificant, and T. heimii might serve as a recorder of changes in seawater delta44/40Ca over geologic time. The Sr/Ca ratios of T. heimii cysts show a pronounced temperature sensitivity (0.016 mmol/mol °C**-1) and have the potential to serve as a palaeo-sea surface temperature proxy. No clear temperature- and pH-dependences were observed for Mg/Ca. U/Ca seems to be influenced by temperature and pH, but the correlations change sign at 23 °C and pH 8.2, respectively.