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1.
We report here on five new cases of solid and cystic papillary neoplasm (SCPN) of the pancreas diagnosed by fine-needle aspiration cytology (FNAC). All cytologic samples were obtained by ultrasonography, and the smears were conventionally fixed and stained. Special histochemical and immunocytochemical stains were also performed in some samples. Cytology revealed in all but one case numerous pseudopapillary structures composed of fibrovascular stalks lined with one or more layers of bland-appearing, uniform tumor cells. The tumor cells had round-to-oval euchromatic nuclei with frequently folded smooth contours and one or two small nucleoli. Their cytoplasm often contained eosinophilic, PAS-positive, and diastase-resistant inclusions. Foamy cells, psammoma bodies, blood, and cellular debris were found in the background. The criteria for the differential diagnosis versus other pancreatic lesions are discussed in some detail, as is the role of immunocytochemistry (ICC). In the literature, only 28 cases of cytologically investigated SCPN have been reported to the best of our knowledge. The most helpful criteria for the conclusive identification of SCPN by FNAC include the pseudopapillary arrangement with bland-appearing tumor cells, and, especially, the finding of acidophilic, PAS-positive, and diastase-resistant cytoplasmic granules. 相似文献
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BACKGROUND: In the adult male rat prostate, castration induces apoptosis of epithelial cells concomitant with the increase in transforming growth factor-beta 1 (TGF-beta 1). In the present study, we investigated the effects of castration on apoptosis and TGF-beta 1 mRNA in neonatal mouse seminal vesicles. METHODS: 5-day-old BALB/c mice were castrated by Pfeifer's method. We estimated the weight, 3H-thymidine uptake by whole seminal vesicles, the amount of TGF-beta 1 mRNA by RT-PCR method, and the apoptotic index of both epithelium and mesenchyme. RESULTS: The castration of 5-day-old neonatal mice resulted in much less weight of seminal vesicles and DNA synthesis estimated by 3H-thymidine uptake by whole seminal vesicles compared to intact neonatal mice, indicating that the growth of neonatal mouse seminal vesicles depends on androgens secreted by the testis. The amount of TGF-beta 1 mRNA estimated by RT-PCR method increased 4 days after castration at 5 days of age. However, the castration did not induce apoptosis in the seminal vesicles. CONCLUSION: The present study indicates that castration of neonatal mice does not induce apoptosis in the seminal vesicles, although it does a transient increase in TGF-beta 1 mRNA in the seminal vesicles. 相似文献
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1. Two basic proteins were purified from secretions of rat seminal vesicles by using Sephadex G-200 chromatography and polyacrylamide-gel electrophoresis under denaturing conditions. 2. It is not certain that these two proteins are distinct species and not subunits of a larger protein, but their properties are similar. Highly basic (pI = 9.7), they migrate to the cathode at high pH and their amino acid composition shows them to be rich in basic residues and serine. Threonine and hydrophobic residues are few. Both proteins are glycoproteins and have mol.wts. of 17000 and 18500. 3. Together these two proteins account for 25-30% of the protein synthesized by the vesicles, but they are absent from other tissues. 4. Changes in androgen status of the animal markedly affect these proteins. After castration, a progressive decrease in the basic proteins is observed and the synthesis of the two proteins as measured by [35S]methionine incorporation in vitro is is decreased. Testosterone administration in vivo rapidly restores their rates of synthesis. 5. These effects on specific protein synthesis are also observed for total cellular protein, and it is suggested that testosterone acts generally on the total protein-synthetic capacity of the cell and not specifically on individual proteins. Proliferative responses in the secretory epithelium may also be involved. 6. The extreme steroid specificity of the induction process suggests that the synthesis of these basic proteins is mediated by the androgen-receptor system. 7. The biological function of these proteins is not clear, but they do not appear to be involved in the formation of the copulatory plug. 相似文献
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The amounts of protein synthesized and secreted (as indicated by [3H]leucine incorporation) by guinea-pig endometrium cultured for 24 h increased 2.1-fold between days 7 and 15 of the oestrous cycle. This increase did not occur if the guinea-pigs were pregnant. In ovariectomized guinea-pigs, oestradiol acting on a progesterone-primed uterus was the optimum stimulus for the maximum increase in endometrial protein synthesis and secretion. The two main proteins synthesized and secreted by day-15 guinea-pig endometrium had molecular masses of 99.8 and 192.1 kDa as determined on Sephacryl S-200HR. The production of the 99.8 kDa protein increased 5.2-fold between days 7 and 15 of the cycle. The 192.1 kDa protein was not detected in secretions produced by day 7 endometrium, and the 99.8 and 192.1 kDa proteins were not detected in secretions produced by day-15 pregnant endometrium. In ovariectomized guinea-pigs, progesterone did not stimulate the synthesis of secreted proteins of molecular masses above 77 kDa. Oestradiol stimulated the synthesis of secreted proteins with molecular masses of 87.8 and 192.1 kDa. However, oestradiol acting on a progesterone-primed uterus stimulated the synthesis of the secreted proteins with molecular masses of 99.8 and 192.1 kDa, which indicates that this combination of steroid hormones may be responsible for the increase in production of these two proteins by the day-15, nonpregnant guinea-pig endometrium. This stimulation by ovarian steroids of the synthesis and secretion of the 99.8 and 192.1 kDa proteins by the guinea-pig endometrium is apparently inhibited during early pregnancy. 相似文献
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Therapy-related acute myeloid leukemias with balanced translocations affecting the 11q23 chromosome region are one of the most serious complications of treatments with topoisomerase II inhibitor drugs as epipodophillotoxins and anthracyclines. 1,2-5 These cases are usually associated with short interval time from previous chemotherapies, absence of myeloid dysplastic phase, hyperleukocytosis and young age. We and others have recently identified and cloned the ALL1 gene at 11q23 band (also named MLL, HRX. Hrxt) which is consistently altered in t-AML following therapies with topo II targeting drugs. However, there are few reports of cases of t-AML, clinically and biologically similar to the subtype of leukemias secondary to exposure to topo II inhibitors drugs but without the involvement of the ALL1 gene. These observations suggest that genes other than ALL1 which are etiopathogenetically relevant for hematological neoplasias are located in this cytogenetic region. 相似文献
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Telomeres, the repetitive non-coding DNA sequences found at the ends of all eukaryotic chromosomes, shorten with each cell division. It has been proposed that telomere shortening may be the counting element of a mitotic clock that keeps track of cell divisions; with shortening to a critical length acting as a senescence signal underlying cellular aging. The enzyme telomerase functions to maintain telomere length, thus allowing unlimited cell division, and has been associated with cellular immortalization and cancer. Stem cells have large, perhaps unlimited, replicative capacities. Since these cells are potentially immortal, we reasoned that they might posses active telomerase. We therefore assayed for telomerase activity in the stem cell enriched pools of the androgen-depleted sex accessory tissues in the castrated male rat. Following castration, the ventral prostate and seminal vesicles of the rat involute, losing approximately 90% of their cells by 21 days. These residual glands persist, and are enriched for stem cells, being capable of fully regenerating these glands if testosterone is re-introduced into the animal. We assayed telomerase activity in extracts from normal, involuted, and regenerating ventral prostate and seminal vesicles. Normal glands were found to be telomerase negative, whereas telomerase activity appeared as these glands involuted following castration. Conversely, telomerase activity disappeared during testosterone-induced regeneration of these residual glands. These results provide strong evidence for the ability of androgen to negatively-regulate telomerase activity in stem cell populations of the rat ventral prostate and seminal vesicles. and represent the first in vivo model system for the modulation of telomerase activity. 相似文献
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STUDY OBJECTIVE: To evaluate the immediate cytologic assessment during CT-guided fine-needle aspiration cytology (FNAC) in the diagnosis of operable indeterminate solitary pulmonary nodules (SPNs). DESIGN: Prospective randomized study. PATIENTS AND METHODS: Two hundred twenty patients with SPN undergoing CT-guided FNAC were divided into two groups. In the first one (group A, 110 patients), a cytologist assessed the adequacy of the sample obtained immediately, and when the sample was considered inadequate, fine-needle aspiration (FNA) was repeated. In the second group (B, 110 patients), an immediate cytologic examination was not performed, but only a gross assessment by the surgeon. Histologic study of the SPN was possible in 217 cases, whereas three patients were followed up radiologically. RESULTS: Adequate samples were obtained in 100% of group A and 88% of group B (p<0.001). The diagnostic accuracy was 99% in group A and 81% in group B (p<0.001). Group A required a mean of 1.22 FNAs compared with 1.10 in group B (p=0.015). The rate of pneumothorax in the whole series was 24%, and statistically significant differences between the two groups were not detected. CONCLUSIONS: Immediate cytologic study significantly increased the adequacy and diagnostic accuracy of CT-guided FNAC of indeterminate SPNs without causing a significant increase of complications. 相似文献
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Characterization of the major proteins of bovine seminal fluid by two-dimensional polyacrylamide gel electrophoresis 总被引:1,自引:0,他引:1
Recently, we demonstrated that the major proteins from bovine seminal plasma BSP-A1, -A2, -A3 and -30-kDa (collectively called BSP proteins) specifically interact with choline phospholipids. These proteins coat the surface of the spermatozoa after ejaculation and are believed to play an important role in membrane modifications occurring during capacitation. In this study we determined the isoelectric point (pl) and analysed the molecular heterogeneity of BSP proteins. Total protein from bovine seminal plasma (CBSP) and purified BSP proteins were iodinated using chloramine T. Samples were reduced, denatured, separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), and visualized by autoradiography. Analysis of CBSP proteins demonstrated the presence of polypeptides migrating in the pH range of 3.5-7.8 and at molecular weights (M(r)) between 6 and 100 kDa. isoforms of each BSP protein were found when purified iodinated proteins were analysed by 2D-PAGE. BSP-A1 was found at a M(r) of 16.5 kDa and in the range of pl of 4.7-5.0; BSP-A2 at 16 kDa and at a pl of 4.9-5.2; BSP-A3 at 15 kDa and at a pl of 4.8-5.2, and BSP-30-kDa at 28 kDa and at a pl of 3.9-4.6. Similar results were obtained with immunolocalization of BSP proteins after Western blot using specific antibodies. The treatment of purified iodinated BSP proteins with neuraminidase increased the pl of BSP-30-kDa to 4.8-5.0 and decreased its M(r) to 25 kDa, but no change was observed for BSP-A1, -A2 and -A3. The treatment of BSP proteins with sulfatase or acid phosphatase modified neither their M(r) nor their pl. Furthermore, when CBSP proteins were separated in 2D-PAGE and the gels stained for glycoproteins with dansyl hydrazine, BSP proteins were among the major glycoproteins found in the bovine seminal plasma. In conclusion, BSP proteins are acidic and have several isoforms. Furthermore, the heterogeneity of BSP-30-kDa is mainly due to its sialic acid content. 相似文献
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A unique case of left ureteral opening into a seminal vesicle, ipsilateral renal hyperplasia and crossed ectopia of the seminal vesicles is reported. This 24-year-old white man underwent a nephroureterectomy for relief of symptoms of lower urinary tract infection. The embryological development of this abnormality is discussed briefly. 相似文献
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Bovine seminal plasma (BSP) contains four similar proteins secreted by the seminal vesicles, designated BSP-A1, -A2, -A3, and -30 kDa. These proteins bind to choline phospholipids on the surface of the sperm after ejaculation. These BSP proteins also interact with heparin, apolipoprotein A-I (apoA-I) and apoA-I associated with high-density lipoprotein (HDL). The HDL and heparin present in the female reproductive tract have been implicated in sperm capacitation and the acrosome reaction (AR). This study was undertaken to determine whether or not these BSP proteins and HDL could modulate the capacitation of sperm, and to determine the combined effect of HDL and heparin on capacitation. Washed bovine epididymal sperm were preincubated in buffer containing BSP proteins, washed, and incubated with lipoproteins (HDL, and low- and very low-density lipoproteins) or liposomes with or without apoA-I in the presence or absence of heparin. The percentage of capacitated sperm was evaluated after the AR was induced with lysophosphatidylcholine. HDL alone (160 microg/ml) after an 8-h incubation stimulated the AR of epididymal sperm. The percentage of HDL-enhanced AR further increased when sperm were preincubated with BSP proteins. ApoA-I-liposomes stimulated the AR more rapidly (5 h, 160 microg/ml) than HDL. When sperm were preincubated with BSP proteins, the percentage of apoA-I-enhanced AR further increased. In contrast, when liposomes without apoA-I or when low- or very low-density lipoproteins or lipoprotein-depleted serum was used, no significant increase in the AR was detected with or without BSP proteins. When heparin and HDL or apoA-I-liposomes were used together, their combined effects on the AR were not additive. These results indicate that BSP proteins modulate the process of capacitation induced by heparin, HDL, and apoA-I-liposomes. 相似文献
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RC Karn 《Canadian Metallurgical Quarterly》1998,36(3-4):105-117
The goals of this study were to determine the steroid-binding specificity of the mouse salivary androgen-binding protein (ABP) family and to ascertain whether there might be other proteins in mouse saliva capable of binding steroids. The optimal conditions for testosterone binding by mouse salivary proteins were determined using a small-scale chromatography system to separate bound from unbound steroid. Testosterone binding appeared to be biphasic but was directly proportional to saliva concentration, with an optimum temperature of 37 degrees C in the second phase. These results were used to develop a steroid-binding protocol to study the steroid specificity of salivary proteins separated by electrophoresis. The ABP family bound testosterone and progesterone well and HO-progesterone and DHT to a lesser extent but did not bind either cholesterol or estradiol. Steroid structural comparisons suggest that binding by ABP is governed by the A ring of the steroid. Another protein that is not a member of the ABP family bound cholesterol specifically but no protein that specifically bound estradiol was observed. 相似文献
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Secretion, endocytosis and transport to the lytic compartment are fundamental, highly coordinated features of the eukaryotic cell. These intracellular transport processes are facilitated by vesicles, many of which are small (100 nm or less in diameter) and 'coated' on their cytoplasmic surface. Research into the structure of the coat proteins and how they interact with the components of the vesicle membrane to ensure the selective packaging of the cargo molecules and their correct targeting, has been quite extensive in mammalian and yeast cell biology. By contrast, our knowledge of the corresponding types of transport vesicles in plant cells is limited. Nevertheless, the available data indicate that a considerable homology between plant and non-plant coat polypeptides exists, and it is also suggestive of a certain similarity in the mechanisms underlying targeting in all eukaryotes. In this article we shall concentrate on three major types of transport vesicles: clathrin-coated vesicles, COP-coated vesicles, and 'dense' vesicles, the latter of which are responsible for the transport of vacuolar storage proteins in maturing legume cotyledons. For each we will summarize the current literature on animal and yeast cells, and then present the relevant data derived from work on plant cells. In addition, we briefly review the evidence in support of the 'SNARE' hypothesis, which explains how vesicles find and fuse with their target membrane. 相似文献
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HS Melkonyan WC Chang JP Shapiro M Mahadevappa PA Fitzpatrick MC Kiefer LD Tomei SR Umansky 《Canadian Metallurgical Quarterly》1997,94(25):13636-13641
Quiescent mouse embryonic C3H/10T1/2 cells are more resistant to different proapoptotic stimuli than are these cells in the exponential phase of growth. However, the exponentially growing 10T1/2 cells are resistant to inhibitors of RNA or protein synthesis, whereas quiescent cells die upon these treatments. Conditioned medium from quiescent 10T1/2 cells possesses anti-apoptotic activity, suggesting the presence of protein(s) that function as an inhibitor of the apoptotic program. Using differential display technique, we identified and cloned a cDNA designated sarp1 (secreted apoptosis-related protein) that is expressed in quiescent but not in exponentially growing 10T1/2 cells. Hybridization studies with sarp1 revealed two additional family members. Cloning and sequencing of sarp2 and sarp3 revealed 38% and 40% sequence identity to sarp1, respectively. Human breast adenocarcinoma MCF7 cells stably transfected with sarp1 or infected with SARP1-expressing adenovirus became more resistant, whereas cells transfected with sarp2 displayed increased sensitivity to different proapoptotic stimuli. Expression of sarp family members is tissue specific. sarp mRNAs encode secreted proteins that possess a cysteine-rich domain (CRD) homologous to the CRD of frizzled proteins but lack putative membrane-spanning segments. Expression of SARPs modifies the intracellular levels of beta-catenin, suggesting that SARPs interfere with the Wnt-frizzled proteins signaling pathway. 相似文献
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BACKGROUND: The use of video-assisted thoracic surgery for diagnosis and treatment of mediastinal tumors in a multiinstitution patient population is not well understood. METHODS: We studied 48 cases from Cancer and Leukemia Group B thoracic surgeons. Of 21 men and 27 women, aged 41 +/- 16 years, 22 patients were asymptomatic. In the others, 92% of tumor-related symptoms improved or resolved after treatment. Five tumors involved the anterior compartment, 19 the middle, and 24 the posterior compartment. Diagnoses were typical for each compartment but also included uncommon problems such as superior vena cava hemangioma and a histoplasmosis cyst causing hoarseness. Of the lesions, a biopsy of 12 was done without excision and the rest were excised completely. Fifteen were cystic and 10 were malignant (8 biopsy only). Maximal dimensions were 5.2 +/- 3.3 cm. RESULTS: Operations were briefer for 24 posterior (93 +/- 41 min) than 5 anterior (195 +/- 46 min, p < 0.01) or 19 middle mediastinal tumors (170 +/- 78 min, p < 0.01). Although 96% had vital mediastinal relations, only six open conversions were performed because of bleeding (n = 3), large size, impaired exposure, or rib attachments, and no patient had morbidity beyond that expected for the thoracotomy. Postoperative stay was shorter for the nonconversion group (3.2 +/- 2.8 versus 5.5 +/- 2.1 days, p = 0.05), as was chest tube duration (1.7 +/- 1.4 days versus 3.2 +/- 1.9 days, p = 0.03). There were no postoperative deaths or major complications, but 7 patients had minor complications. During a mean of 20 months of surveillance (range, 1 to 52 months), one cyst recurred (asymptomatic) as did one sarcoma that was excised. CONCLUSIONS: Video-assisted thoracic surgery is a safe technique for benign mediastinal tumors, typically those in the middle and posterior mediastinum. 相似文献
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Pathogenic Salmonella species initiate infection of a host by inducing their own uptake into intestinal epithelial cells. An invasive phenotype is conferred to this pathogen by a number of proteins that are components of a type III secretion system. During the invasion process, the bacteria utilize this secretion system to release proteins that enter the host cell and apparently interact with unknown host cell components that induce alterations in the actin cytoskeleton. To investigate the role of secreted proteins as direct modulators of invasion, we have evaluated the ability of Salmonella typhimurium to enter mammalian cells that express portions of the Salmonella invasion proteins SipB and SipC. Plasma membrane localization of SipB and SipC was achieved by fusing carboxyl- and amino-terminal portions of each invasion protein to the intracellular carboxyl-terminal tail of a membrane-bound eukaryotic receptor. Expression of receptor chimeras possessing the carboxyl terminus of SipB or the amino terminus of SipC blocked Salmonella invasion, whereas expression of their chimeric counterparts had no effect on invasion. The effect on invasion was specific for Salmonella since the perturbation of uptake was not extended to other invasive bacterial species. These results suggest that Salmonella invasion can be competitively inhibited by preventing the intracellular effects of SipB or SipC. In addition, these experiments provide a model for examining interactions between bacterial invasion proteins and their host cell targets. 相似文献
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JJ Thomas B Falk C Fenselau J Jackman J Ezzell 《Canadian Metallurgical Quarterly》1998,70(18):3863-3867
Matrix-assisted laser desorption/ionization mass spectrometry has enabled viral coat proteins to be characterized directly from the virus. This analysis, demonstrated here with tobacco mosaic virus U2, a bacteriophage MS2, and equine encephalitis TRD, is achieved with a combination of organic acid, UV-absorbing matrix, and high-energy desorption with a nitrogen laser. The molecular weights of these proteins are determined with sufficient accuracy to allow differentiation among viral species and strains. The abundant hydrophobic MS2 coat protein was analyzed in aliquots of culture medium and of the tobacco mosaic virus coat protein in infected leaves. This method provides rapid detection of coat protein in the low-femtomole range, as estimated by titering plaque-forming units of MS2. 相似文献
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With the use of retrograde tracing techniques, selective spinal nerve transections, and immunohistochemistry to label noradrenergic and peptidergic pathways, this study has for the first time defined in detail the autonomic innervation to the rat seminal vesicles. The majority of this innervation originates from the bilateral major pelvic ganglia, whereas very few neurons are located in the accessory, inferior mesenteric, or paravertebral chain ganglia. Neuropeptide Y was the most abundant marker, followed by tyrosine hydroxylase (an enzyme involved in noradrenaline synthesis), and then vasoactive intestinal peptide. Sympathetic axons with tyrosine hydroxylase and neuropeptide Y supplied vascular and nonvascular smooth muscle whereas parasympathetic, cholinergic neuropeptide Y terminals were associated with the glandular epithelium. In contrast, vasoactive intestinal peptide was found only in cholinergic neurons, which may have either parasympathetic or sympathetic spinal connections. The latter were far more prevalent, demonstrating a substantial sympathetic cholinergic innervation to the seminal vesicles. Vasoactive intestinal peptide axons were associated with the glandular epithelia, as well as vascular and nonvascular smooth muscle. Axons associated with the secretory epithelia may regulate secretion or perhaps provide trophic support. Finally, acute damage to preganglionic sacral and lumbar nerves caused a transient increase in glandular weight. 相似文献