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11.
Jason E. Farrar Paola Quarello Ross Fisher Kelly A. O'Brien Anna Aspesi Sara Parrella Adrianna L. Henson Nancy E. Seidel Eva Atsidaftos Supraja Prakash Shahla Bari Emanuela Garelli Robert J. Arceci Irma Dianzani Ugo Ramenghi Adrianna Vlachos Jeffrey M. Lipton David M. Bodine Steven R. Ellis 《American journal of hematology》2014,89(10):985-991
Diamond Blackfan anemia (DBA), a syndrome primarily characterized by anemia and physical abnormalities, is one among a group of related inherited bone marrow failure syndromes (IBMFS) which share overlapping clinical features. Heterozygous mutations or single‐copy deletions have been identified in 12 ribosomal protein genes in approximately 60% of DBA cases, with the genetic etiology unexplained in most remaining patients. Unlike many IBMFS, for which functional screening assays complement clinical and genetic findings, suspected DBA in the absence of typical alterations of the known genes must frequently be diagnosed after exclusion of other IBMFS. We report here a novel deletion in a child that presented such a diagnostic challenge and prompted development of a novel functional assay that can assist in the diagnosis of a significant fraction of patients with DBA. The ribosomal proteins affected in DBA are required for pre‐rRNA processing, a process which can be interrogated to monitor steps in the maturation of 40S and 60S ribosomal subunits. In contrast to prior methods used to assess pre‐rRNA processing, the assay reported here, based on capillary electrophoresis measurement of the maturation of rRNA in pre‐60S ribosomal subunits, would be readily amenable to use in diagnostic laboratories. In addition to utility as a diagnostic tool, we applied this technique to gene discovery in DBA, resulting in the identification of RPL31 as a novel DBA gene. Am. J. Hematol. 89:985–991, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
12.
Alphonse Krystosek Shahla Verrall Nicholas W. Seeds 《International journal of developmental neuroscience》1988,6(5):483-493
The molecular characterization of neural secretory plasminogen activators and their possible association with two well-defined Schwann cell activities (mitosis and migration) were investigated. Schwann cells from peripheral sensory ganglion roots were established as primary cultures of high purity. Conditioned culture medium was fractionated by gel electrophoresis and assayed for plasminogen-dependent in situ caseinolytic activity. Both tissue-type and urokinase-type plasminogen activators were detected early in culture. The amount of the tissue-type form decreased with increasing time in culture. Proliferative ability measured as [3H]thymidine incorporation into the nucleus varied under several culture conditions and was lowest in defined serum-free medium; however, these serum-free cultures expressed the highest level of plasminogen activator secreting cells. Combined autoradiography/fibrin overlay assays allowed for a direct analysis at the single cell level; interestingly the findings did not support the idea of an obligatory expression of the enzyme in replicating cells. Cell motility was assayed in combined gold particle clearing/fibrin overlay assays and likewise no obligatory association of protease secretion and cell movement could be demonstrated. The results are discussed in relation to previous studies in this field. 相似文献
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BACKGROUND: Congenital mediastinal teratomas are rare and may present with nonimmune hydrops. The lesion may be misinterpreted on ultrasound. CASES: A 21-year-old woman, gravida 2, para 0111, was evaluated at 19 4/7 weeks of gestation for suspected fetal death. An ultrasonogram confirmed the death and revealed a posterior encephalocele and possible herniated liver in the chest. At autopsy a 5.2 x 7.5 x 1.0-cm mediastinal teratoma completely compressed the chest organs. No encephalocele was present. A 15-year-old woman, gravida 1, para 0, underwent an ultrasonogram at 27 weeks when fetal heart rate decelerations were detected. The ultrasound revealed hydrops and suggested a calcified left cardiac ventricular wall and diaphragmatic hernia. Autopsy of the stillborn female showed an 8.0 x 6.0 x 4.0-cm teratoma in the mediastinum, with small heart and lungs. A 23 2/7 weeks stillborn female was delivered to a 32-year-old woman, gravida 5, para 2, and noted to be hydropic. Ultrasound had suggested multiple anomalies and hydrops. Autopsy revealed a 23 g, 4.5 x 3.0 x 3.0-cm teratoma that filled the anterior mediastinum. CONCLUSION: Congenital mediastinal teratoma may be associated with fetal death. It is within the differential diagnosis of nonimmune hydrops, particularly if a thoracic mass is detected on ultrasonography. 相似文献
14.
Husain A. Saleh M.D. F.I.A.C. M.B.A. Mohammad El‐Fakharany M.D. Hassan Makki M.D. F.C.C.P. Ahmad Kadhim M.D. Shahla Masood M.D. 《Diagnostic cytopathology》2009,37(5):324-332
Differentiating reactive mesothelial cells (RMs) from metastatic adenocarcinoma cells (MAC) in serous fluids based on cytomorphologic features alone can be very challenging. Various immunocytochemical (ICC) markers have been used to maximize the diagnostic accuracy, however, cytopathologists still encounter difficulties in effusion cytologic diagnosis. The aim of this study was to evaluate previous and recent ICC stains to identify the most sensitive and specific markers and the best panel for differentiating RM from MAC. Cell block sections from 41 MAC and 43 RM effusions cases were subjected to ICC staining for MOC‐31, BerEp4, carcinoembryonic antigen (CEA), calretinin, HBME‐1, CK5/6, and D2‐40. For the MAC cases, the sensitivity of BerEp4, MOC‐31, and CEA was 82.9, 92.6, and 17%, respectively, and the specificity was 95.3, 93, and 100%, respectively. For the RM cases, the sensitivity of calretinin, CK5/6, D2‐40, and HBME‐1 was 95.3, 27.9, 58.1, and 93%, respectively, and the specificity was 70.7, 73.1, 75.6, and 82.9%, respectively. The results show that BerEp4 and MOC‐31 are highly sensitive and specific for detecting MAC, whereas calretinin and HBME1 are highly sensitive but only modestly specific for detecting RM cases (P < 0.05). Forced entry logistic regression revealed that using MOC‐31, BerEp4, HBME‐1, and calretinin, is an excellent panel for making correct diagnosis with 97.6% sensitivity in detecting MAC and 90.7% specificity in detecting RM. We conclude that adding a panel of MOC‐31, BerEp4, calretinin, and HBME‐1 immunostains to routine cytomorphologic features can greatly enhance the diagnostic accuracy of serous effusions. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
15.
The existence of inhibitory short- and ultrashort-loop feedback mechanisms for luteinizing hormone (LH), while documented in animals, has been questioned in humans. Since human chorionic gonadotropin (hCG) binds to LH receptors but can be distinguished from LH in immunoassays, it is possible to identify LH surges in the face of exogenously administered hCG. The present study demonstrates LH surges at midcycle in normal volunteers and in women undergoing controlled ovarian hyperstimulation, given hCG. This provides further evidence for lack of loop feedback control of LH secretion in humans. 相似文献
16.
BACKGROUND: Invasive ductal carcinoma of the breast is a heterogeneous collection of divergent types of carcinomas. Some subtypes have been characterized by histologic observations. This study describes a distinctive subset recognized through cytomorphologic examination of breast carcinoma specimens obtained by fine-needle aspiration biopsies (FNAB). Identification of this subset is established further by analyses of its clinical and immunologic characteristics. METHODS: One hundred patients underwent FNAB and were diagnosed with breast ductal carcinoma. These diagnoses were followed by surgical resections and histologic evaluation of tumors. Immunohistochemical analyses of estrogen receptor, progesterone receptor, Her2/neu, p53 protein, and Ki-67 were performed. Patient's age, race, and family history of breast carcinoma were obtained. The objective of the study is to identify a cytomorphologically distinctive, clinically relevant, subset of breast carcinomas. RESULTS: A subset carcinoma was recognized by cytomorphologic examination of Pap-stained FNAB slides. This subset consisted of seven patients with a median age of 37 years. At the time of surgical resection, all patients had axillary lymph node metastases. Six of seven patients had distant metastases. Immunohistochemical studies revealed that all tumors are positive for p53 protein and negative for estrogen and progesterone receptors. CONCLUSION: This study presented a unique subset of breast ductal carcinomas that involved young patients and had aggressive growth behavior. These tumors expressed p53 protein but not estrogen and progesterone receptors. 相似文献
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Langerhans cells histiocytosis in one family 总被引:2,自引:0,他引:2
Histiocytosis of Langerhans cells (class 1 histiocytosis) includes a range of clinical manifestations that have been described as bone eosinophilic granuloma, Hand-Schüller-Christian syndrome, and Letterer-Siwe diseases. This syndrome represents a spectrum of severity and prognosis of some underlying disorder which is usually sporadic. This report describes three cases in one family, who developed the disease a few years after their brother was found to be suffering from histiocytosis. All 3 patients had the same clinical manifestations: hyperthermia, eczematic rash, and swelling in skull, hand, and foot. X rays showed lytic areas in the skull and metacarp of fourth finger. Serology for EBV infection was negative. Infiltration of abnormal Langerhans cells histiocytes were demonstrated in bone biopsies. These patients were given chemotherapy. Case 1 (brother) died 1 year after chemotherapy, case 2 (girl) was given chemotherapy without success. She was given T-cell suppressor (cyclosporine), which induced remission, and case 3 was given chemotherapy, which was successful. 相似文献
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