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181.
Słowińska-Klencka D Sporny S Klencki M Popowicz B Lewiński A 《Endokrynologia Polska》2006,57(4):299-306
INTRODUCTION: Lowered and non-homogenous echogenicity in patients with chronic thyroiditis (CT) may cause problems in revealing focal lesions in ultrasound scans. Moreover, frequent anisocytosis of thyroid follicular cells and of oncocytes may falsely suggest neoplastic growth. The aim of the study was to evaluate the frequency of CT diagnosed in patients subjected to fine-needle aspiration biopsy (FNAB) of the thyroid in years 1994-2005, as well as to assess the cancer frequency in the operated patients with CT. MATERIAL AND METHODS: As much as 23 173 cytological reports and corresponding outcomes were analyzed and in patients treated surgically verified against postoperative histopathological examinations. Moreover, the analysis of cytological smears in CT with distinguishing its types (lymphocytic, epithelial-hyperplastic, colloidal, oxyphillic) was performed in 50 patients; the changes between subsequent FNABs in the picture of the smears were also assessed. RESULTS: The frequency of diagnosed CT had been increasing in the evaluated time span from 2.6% to 9.7% (p < 0.0001). There were 11 cases of papillary carcinoma found coexisting with CT. The analysis of cytological types of CT showed that the lymphocytic type prevailed over the others (lymphocytic - 43%, colloidal--21%, epithelial-hyperplastic--20%, oxyphilic--16%, p < 0.001). The evolution in time of the cytological picture was observed. CONCLUSION: The increase in the frequency of CT observed in smears obtained from the thyroid gland and the reports on the coexistence of CT with papillary carcinoma suggest the necessity of prudent diagnostics and follow-up of patients with CT. 相似文献
182.
Myśliwiec P Gryko M Kedra B Zalewski B Kowalska I Myśliwiec J 《Endokrynologia Polska》2006,57(2):166-171
Neuroendocrine tumors are rare gastrointestinal tract disorders, in which diagnosis and treatment are often difficult. The aim of the paper is to present two cases of patients with neuroendocrine tumor of gastrointestinal tract, who underwent surgical procedure in II Department of General and Gastroenterological Surgery of Medical University of Bia?ystok in 2005. A 63-year-old female patient with primary diagnosis of neuroendicrine tumor metastases in liver was not successfully investigated for primary tumor in the preoperative period. The laparotomy procedure indicated the malignant neuroendocrine tumor in the terminal ileum and metastases to the liver and to the greater omentum. The right hemicolectomy and liver metastatic segment VII and VIII resection were performed. The neurological disturbances of obscure origin were observed in the postoperative period and the patient suddenly died on the 15(th) day after surgery. A 57-years-old male patient was operated on for lymph node recurrence of gastric tumor. Pathologic examination of tissue sample revealed the diagnosis of carcinoid. The patient underwent subtotal gastric resection for a pyloric ulcer, diagnosed as Adenocarcinoma G2 pT2N0M0 6 years before. Liver and abdominal node metastases, confirmed by octreoscan, were observed after lymphadenectomy, The treatment of somatostatin analogues (LAR octreotide) was used. In spite of therapy the patient died. The authors present their own experiences and show the preoperative diagnostic difficulties in patients with neuroendocrine gastrointestinal tumors. Unexpected neurological complications in the treatment course were described. 相似文献
183.
184.
Skwarczynski M Noguchi M Hirota S Sohma Y Kimura T Hayashi Y Kiso Y 《Bioorganic & medicinal chemistry letters》2006,16(17):4492-4496
A prodrug of paclitaxel which has a coumarin derivative conjugated to the amino acid moiety of isotaxel (O-acyl isoform of paclitaxel) has been synthesized. The prodrug was selectively converted to isotaxel by visible light irradiation (430 nm) with the cleavage of coumarin. Finally, paclitaxel was released by subsequent spontaneous O-N intramolecular acyl migration. 相似文献
185.
Mariusz Pawel Kowalewski Hakki Bülent Beceriklisoy Selim Aslan Ali Reha Agaoglu Bernd Hoffmann 《Animal reproduction science》2009,116(1-2):129-138
In nonpregnant and pregnant dogs the corpora lutea (CL) are the only source of progesterone (P4) which shows an almost identical secretion pattern until the rapid decrease of P4 prior to parturition. For the nonpregnant dog clear evidence has been obtained that physiological luteal regression is devoid of a functional role of the PGF2α-system and seems to depend on the provision of StAR. Yet in pregnant dogs the rapid prepartal luteal regression, coinciding with an increase of PGF2α, may be indicative for different regulatory mechanisms. To assess this situation and by applying semi-quantitative Real Time (Taq Man) RT-PCR, expression patterns were determined for the following factors in CL of pregnant and prepartal dogs and of mid-pregnant dogs treated with the antiprogestin Aglepristone: cyclooxygenase 2 (Cox2), prostaglandin E2 synthase (PGES), prostaglandin F2α synthase (PGFS), its receptors (EP2, EP4 an FP), the steroidogenic acute regulatory protein (StAR), 3β-hydroxysteroid-dehydrogenase (3βHSD) and the progesterone receptor (PR). Peripheral plasma P4 concentrations were determined by RIA. CL were collected via ovariohysterectomy from pregnant bitches (n = 3–5) on days 8–12 (Group 1, pre-implantation period), days 18–25 (Group 2, post-implantation period), days 35–40 (Group 3, mid-gestation period) and during the prepartal progesterone decline (Group 4). Additionally, CL were obtained from groups of 5 mid-pregnant dogs (days 40–45) 24 h, respectively 72 h after the second treatment with Aglepristone. Expression of Cox2 and PGES was highest during the pre-implantation period, that of PGFS and FP during the post-implantation period. EP4 and EP2 revealed a constant expression pattern throughout pregnancy with a prepartal upregulation of EP2. 3βHSD and StAR decreased significantly from the pre-implatation period to prepartal luteolysis, it was matched by the course of P4 concentrations. Expression of the PR was higher during mid-gestation and prepartal luteolysis than in the two preceding periods. After application of Aglepristone the overall mRNA-expression resembled the situation during prepartal luteolysis except for EP2, which remained unchanged.These data suggest that – as in the nonpregnant bitch – also in the pregnant bitch luteal production of prostaglandins is associated with luteal support rather than luteolysis. On the other hand induction of luteolysis by the PR blocker Aglepristone points to a role of luteal P4 as an autocrine factor in a positive loop feedback system controlling the availability of P4, StAR and 3βHSD. 相似文献
186.
More than one hundred centrodorsals of the comatulid crinoid Glenotremites paradoxus have been found in Turonian deposits (Upper Cretaceous) in the Miechów-Wolbrom area (southern Poland). This is the first dense occurrence of the genus Glenotremites in the Upper Cretaceous of Poland. Furthermore, so many individuals of this species in one level (the so-called Conulus Bed) forming a crinoid Konzentrat-Lagerstätte are very surprising because only disarticulated remains (cirrals and brachials) are encountered in the older (Cenomanian and earliest Turonian) and younger (late Turonian) deposits. The Glenotremites individuals are accompanied by isocrinids, which prove that stalked forms remained in shallow-water settings for some time after the initiation of the Mesozoic marine revolution. 相似文献
187.
Mariusz T. Skowronski Tae-Hwan Kwon S?ren Nielsen 《The journal of histochemistry and cytochemistry》2009,57(1):61-67
Thirteen mammalian aquaporin (AQP) isoforms have been identified, and they have a unique tissue-specific pattern of expression. AQPs have been documented in the reproductive system of both male and female humans, rats, and mice. However, tissue expression and cellular and subcellular localization of AQPs are unknown in the female reproductive system of pigs. In this study, AQP1 immunoreactivity was detected in the capillary endothelium of the ovary. Distinct immunolabeling of capillary endothelium was also observed in the oviduct and uterus. AQP5 was expressed in flattened follicle cells of primordial follicles, granulosa cells of developing ovarian follicles, and muscle cells of the oviduct and uterus. Staining of AQP5 was also observed in the epithelial cells of the oviduct and uterine epithelium. AQP9 immunoreactivity was observed in granulosa cells of developing follicles. AQP9 was also localized in the luminal epithelial cells of the oviduct and uterine epithelia cells. This is, to our knowledge, the first study that shows tissue expression and cellular and subcellular localization of AQPs in the reproductive system of the female pig. Moreover, these results suggest that several subtypes of the AQPs (AQP1, 5, and 9) are involved in regulation of water homeostasis in the reproductive system of gilts. 相似文献
188.
Amphotericin B (AmB) is considered the gold-standard in the treatment of serious systemic mycoses despite its numerous adverse effects. Both the mechanism of antifungal action and the toxicity of this drug are dependent on its molecular organization. The effect of AmB on the organization of lipid membranes formed with dipalmitoylphosphatidylcholine (DPPC) was studied with application of the Langmuir-Blodgett technique and ATR-FTIR spectroscopy. The aim of this research was to analyze the physical interactions leading to the formation of aggregated forms of AmB molecules in one-component monolayers and lipid multibilayers. Analysis of FTIR spectra of two-component multibilayers suggests the possibility the mutual reorientation of the amino-sugar moiety (mycosamine) and macrolide ring. This effect may be significant in the explanation of the aggregation processes of AmB in biological systems. 相似文献
189.
Dong-Myung Shin Rui Liu Izabela Klich Janina Ratajczak Magda Kucia Mariusz Z. Ratajczak 《Molecules and cells》2010,29(6):533-538
Pluripotent very small embryonic/epiblast derived stem cells (VSELs) as we hypothesize are deposited at begin of gastrulation
in developing tissues and play an important role as backup population of pluripotent stem cells (PSCs) for tissue committed
stem cells (TCSCs). We envision that during steady state conditions these cells may be involved in tissue rejuvenation and
in processes of regeneration/repair after organ injuries. Molecular analysis of adult bone marrow (BM)-derived purified VSELs
revealed that they i) express pluripotent stem cells markers e.g., Oct4, Nanog, Klf-4, SSEA-1 ii) share several markers characteristic
for epiblast as well as migratory primordial germ cells (PGCs), and iii) possess a unique pattern of genomic imprinting (e.g.,
erasure of differently methylated regions at Igf2-H19 and Rasgrf1 loci and hypermethylation at KCNQ1 and Igf2R loci). This
supports that VSELs are related to epiblast-derived migrating PGC-like cells and, despite their pluripotent stem cell character,
changes in the epigenetic signature of imprinted genes keep these cells quiescent in adult tissues and prevent them from teratoma
formation. In contrast epigenetic changes/mutations that lead to activation of imprinted genes could potentially lead to tumor
formation by these cells. Mounting evidence accumulates that perturbation of expression of imprinted genes is a common phenomenon
observed in developing tumors. 相似文献
190.
Andrzej Mariusz Szczepański Alina Grzanka Anna Litwiniec Lidia Gackowska Izabela Kubiszewska Dariusz Grzanka 《Cell biology international》2010,34(2):197-211
The cytoskeleton is a ubiquitous cellular structure that plays a crucial role in most processes of living cells. There are reports suggesting that this system not only reflects, but also contributes to many different processes, including cell death. In this study, we examined alterations of both MT and MF cytoskeletal systems related to cell death, which was induced in A549 cells by continuous cisplatin treatment. We observed that specific changes in these cytoskeletal proteins accompany cell death, while the others are associated with increased repair and cell survival. It seems that the predominant mode of cell death triggered by cisplatin was an apoptotic‐like pathway, but on the other hand, coincidence with some features of necrosis and autophagy was also demonstrated in our conditions. 相似文献