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1.
Cystic fibrosis (CF) and Crohn's disease may both present as failure to thrive and recurrent intestinal obstruction. Proper treatment and adequate nutrition may reverse these manifestations and improve the patient's quality of life. We describe a girl with CF who, despite appropriate management, failed to grow and had several episodes of bowel obstruction. After the additional diagnosis of Crohn's disease was reached, the patient improved on antiinflammatory and nutritional therapy. This patient illustrates the pitfall in the diagnosis of Crohn's disease in a CF patient due to the clinical overlap between the two conditions. We suggest that therapeutic failure in a chronic disease justifies additional diagnostic efforts resulting in a completion of diagnosis and significant changes in management.  相似文献   
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Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals.  相似文献   
4.
Pigmentosis tubae (PT) is a rare condition characterized by the presence of numerous lipofuscin-laden macrophages in the lamina propria of the fallopian tube. Two women, who also had endometriotic ovarian cysts, showed polypoid pigmented tubal mucosae. In addition to lipofuscin, occasional cells showed spotty positivity for iron. Ultrastructural examination of the tubal mucosa showed the lipofuscin-containing bodies, which were similar to lipofuscin-containing lysosomes found in other pigmented conditions. Cytoplasmatic ferritin and hemosiderin in siderosomes were observed in macrophages and endothelial cells of the lamina propria. The present study is the first to demonstrate the presence of iron-containing particles and lipofuscin in the residual bodies of PT. The origin of the excess iron is not clear, but erythrophagocytosis and an abnormal tubal environment could play a role. Iron-promoted lipid peroxidation may alter the lysosomal membranes and contribute to the excessive accumulation of lipofuscin in these cells.  相似文献   
5.
Hepatic iron content was determined in post mortem specimens from a wide range of avian species collected over a 12-month period. The majority (> 90%) of these specimens (n = 40) showed high iron content (up to 12 mg Fe/g tissue). The highest concentrations were associated with fibrosis and regenerative nodules. Dietary analysis indicated that the iron intake was not excessive, suggesting that iron-loading was due to enhanced intestinal absorption.  相似文献   
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BACKGROUND/AIMS: The recovery from iron overload is hampered by the limited number of pathways and therapeutic agents available for the augmentation of iron secretion/excretion. The present study was aimed to investigate the process of iron storage and release by cultured human hepatoma cells, the role of transferrin receptors and ferritin in this process as well as the effect of iron chelators. METHODS: We followed the acquisition, storage and release of iron by cultured cells HepG2 and Hep3B by biochemical means and electron microscopy. RESULTS: The uptake of iron from diferric transferrin (Trf) was extremely low, while iron as ferric-ammonium-citrate (FAC) was taken up readily, especially by Hep3B cells. Up to 80% of the iron taken up by hepatoma cells was released to the medium. The rate of spontaneous iron release depended on the extent of iron loading. ApoTrf and deferoxamine facilitated release after 1- and 7-day iron-exposure. Up to a third of the radio-iron released from the cells was associated with ferritin. The release of ferritin-iron was not enhanced by either deferoxamine or Trf. CONCLUSIONS: Ferritin-iron release appeared to be an important mechanism of iron discarding in cultured human hepatoma cells, independent of the activity of chelating agents.  相似文献   
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The clinical, histopathological, and electron microscopic features of an unusual case of xanthogranulomatous appendicitis are reported. The patient, a 37-year-old female, presented with typical signs of acute appendicitis and the appendix appeared slightly dilated at laparatomy. The histopathological sections showed numerous xanthoma cells mixed with inspissated fecaliths. Electron microscopy disclosed the presence of xanthoma cells filled with electron-lucent lipid droplets of variable size. The ultrastructural characteristics of these cells enabled the distinction of two types of lipid-laden histiocytes, in relationship to the size of the lipid droplets. Since the lipid droplets were seen also in cells other than histiocytes, it appears that these changes are secondary to a common mechanism,comprising factors such as obstruction, hemorrhage, inflammation,and local hypoxia.  相似文献   
9.

Aim

To establish allele frequencies and genetic parameters for 5 new European Standard Set short tandem repeat (STR) loci in the population of Romania and to compare them with those in other populations.

Methods

DNA was isolated using QIAamp 96 DNA Swab BioRobot Kit and Chelex 100 methods. Polymerase chain reaction amplification was done using Investigator ESSplexPlus Kit (D1S1656, D2S441, D2S1338, D3S1358, D8S1179, D10S1248, D12S391, D16S539, D18S51, D19S433, D21S11, D22S1045, FGA, TH01, and vWA). For DNA typing, Applied Biosystems 3500/3500xL Genetic Analyzer was used. Statistical analysis was done using Powerstats, GDA, and Arlequin software.

Results

Power of discrimination and polymorphism information content was highest for two new ESS loci, D1S1656 and D12S391. Comparison of allele frequencies for 5 new ESS loci in Romanian population with previously published population data showed significant differences for all compared populations, with the exception of Hungary. Geographically more distant populations, such as Spain, Sweden, United Kingdom, Germany, and Portugal differed more than closer populations.

Conclusion

New ESS STR loci are very useful for the analysis of forensic samples (persons or traces) due to their characteristics (shortness and high polymorphism). In comparisons with other common STR markers, they have a higher power of discrimination and also higher polymorphism information content, and could be used in any national DNA database.The establishment of standard sets (or common sets) of short tandem repeat (STR) markers which had first been a necessity for the forensic scientific community, as a result of globalization became a necessity for the worldwide law enforcement agencies. STR markers standard sets facilitate communication and judicial transmission of the forensic DNA typing results between different forensic groups or countries (1).Although several STR sets have been proposed (2), three of them are most frequently used: Interpol Standard Set of Loci – ISS (FGA, TH01, VWA, D3S1358, D8S1179, D18S51, D21S11), US Core Loci – CODIS (CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11), and European Standard Set of Loci – ESS (D3S1358, VWA, D8S1179, D21S11, D18S51, TH01, FGA, D1S1656, D2S441, D10S1248, D12S391, D22S1045).The five new European Standard Set STR loci studied in Romanian population are an upgrade of an earlier version of ESS consisiting of 7 STRs (3), adopted by the European Council in 2001. The DNA Working Group of the European Network of Forensic Science Institutes (ENFSI) reviewed the usefulness of the ESS in light of the increased exchange of DNA analysis results in 2009 and recommended the expansion with 5 new ones (4).Romania adopted the new 5 ESS loci and started to use them at the national level at the beginning of 2012 as part of the Investigator ESSplex Plus Kit, which replaced the AmpFlSTR Identifiler PCR Amplification Kit used before for Romanian National DNA Database supplying. As a consequence, and due to the lack of any study involving D10S1248, D22S1045, D2S441, D1S1656, and D12S391 loci in the Romanian population, allele distribution and genetic parameters of these loci have to be determined. The aim of this study was to establish allele frequencies and genetic parameters for 5 new ESS loci in population of Romania and to compare them with those in other populations .  相似文献   
10.
Rectal resections are the only treatment with curative intent currently accepted world wide. When performed in elective circumstances, laparoscopic rectal excision is technically feasible in surgical approach of mid-rectal cancer in a considerable number of patients. There are many benefits of the laparoscopic approach to rectal resection such as short hospitalization, less pain, less postoperative complications and improved quality of life. However, one mandatory condition in laparoscopic resection of rectum includes complete excision of the rectum and mesorectum, generally ensuring a minimal distal margin of 2cm and circumferential radial clearance before performing a coloanal anastomosis. Here, we present a laparoscopic approach for rectal cancer treatment consisting in a wide resection of the rectum, including the entire fascia with the enclosed mesentery of the rectum.  相似文献   
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