STANDARD IMAGING TECHNIQUES OF ENDOSCOPIC ULTRASOUND‐GUIDED FINE‐NEEDLE ASPIRATION USING A CURVED LINEAR ARRAY ECHOENDOSCOPE

Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.     

Rounded atelectasis: diagnosis by fine-needle aspiration cytology.

Rounded atelectasis, a rare, benign mass lesion, is most often seen in association with asbestos-related pleural changes. Often a presumptive diagnosis can be made on the basis of characteristic CT and chest radiographic findings. However, not infrequently radiographic imaging fails to differentiate rounded atelectasis from primary bronchogenic carcinoma, a disease which is seen with increased frequency in patients with asbestos exposure. We describe two cases where the diagnosis of rounded atelectasis was made by fine-needle aspiration (FNA) cytology. The cytologic features included abundant pulmonary parenchymal material with thickened alveolar walls containing pulmonary macrophages and connective tissue. It is important to realize that this is a useful positive finding indicating rounded atelectasis, rather than a negative finding suggesting the absence of neoplasm. Needles with a cutting action may be necessary to obtain sufficient material to make the diagnosis of rounded atelectasis.     

Preferential expansion of Ly-1 B and CD4 CD8 T cells in the polyclonal lymphocyte responses to murine T.cruzi infection

Acute murine infection with T.cruzi results in polyclonal lymphocyteresponses manifested by blast transformation of a large fractionof B, CD4+, and CD8+ cells. We describe here the finding ofsignificant increases in the splenic representation of minorpopulations, Ly-1+ B cells and CD4-CD8- T cells. These lymphocytepopulations might play an important role in the host response,as shown by T.cruzi infection of hosts that had been lethallyirradiated and reconstituted with autologous bone marrow. Underthese conditions, the splenic polyclonal PFC responses are nearlyabrogated, and not restored by the transfer of syngeneic peritonealcells which, however, reconstitute T15 idiotype production inthe same hosts. Control levels of PFC responses, however, arereconstituted by transfer of syngeneic splenic T cells. Sincebone marrow-reconstituted animals contain normal numbers ofCD4+ and CD8+ T cells which are actually activated by infection,these results suggest the participation of other T cell populationsin the host response to infection, as also suggested by themarked increases in T cell receptor and messages detectedin the spleen of infected animals. The implications of thesefindings in immunopathology of Chagas' disease are discussed.     

Intracytoplasmic and intranuclear Reinke's crystals in a testicular Leydig-cell tumor diagnosed by fine-needle aspiration cytology: a case report with review of the literature

We report on the cytopathologic findings of a Leydig-cell tumor of the testis in a young adult male with no evidence of endocrine dysfunction. The preoperative diagnosis was based on fine-needle aspiration cytology (FNAC) alone, which was subsequently confirmed on histopathology. The present case was of interest on account of the paucity of literature regarding the cytodiagnosis of this lesion. In addition, the finding of intracytoplasmic lipofuscin pigment and several intracytoplasmic as well as intranuclear Reinke's crystals served to clinch the diagnosis on FNA. Therefore, the use of FNAC, especially in the presence of diagnostic Reinke's crystals, may vitiate the need for more invasive biopsy procedures in the preoperative diagnosis of testicular Leydig-cell tumors.     

Diagnostic value of DNA flow cytometry combined with fine needle aspiration biopsy in lymphomas

The nuclear DNA content of cells from 45 malignant lymphomas and from 60 benign lymph nodes obtained by fine needle aspiration was analysed to investigate the diagnostic value of DNA flow cytometry combined with routine diagnostic cytology in lymphomas. DNA aneuploidy was found in 43 per cent of lymphomas of high grade malignancy (NCI Working Formulation) but only rarely in lymphomas of intermediate- or low-grade malignancy or in Hodgkin's disease, and never in benign lymph nodes. The median percentage of proliferative cells (S + G2/M) was 22.6 per cent in diploid high-grade lymphomas, 15.3 per cent in intermediate-, and 8.1 per cent in low-grade lymphomas, as compared with 4.9 per cent in benign lymph nodes (P less than 0.0001). If the presence of DNA aneuploidy or more than 12 per cent of proliferative cells is used as a criterion for malignancy, the diagnostic accuracy of DNA flow cytometry in detecting lymphoma is 81 per cent. DNA flow cytometry suggested correct diagnosis in 10 of the 19 false positive, false negative, or indeterminate cytological findings encountered during the study. It is concluded that DNA flow cytometry combined with fine needle aspiration biopsy has diagnostic value in lymphomas, but false negative results are common especially in low-grade lymphomas; the method should therefore be used in conjunction with light microscopy.     

Cytological diagnosis of nonulcerative penile neoplasms: report of two cases

Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis.     

吗氯贝胺与米帕明治疗抑郁症多中心双盲对照试验

目的 :以经典抗抑郁药物米帕明为阳性对照药采用随机双盲双模拟方法对吗氯贝胺和米帕明治疗抑郁症的疗效和安全性进行研究。方法 :共纳入病人 2 0 0例 ,分别口服吗氯贝胺 3 0 0 -60 0mg d或米帕明75 -2 5 0mg d。结果 :两组病人Hamilton抑郁量表 (HAMD)以及Hamilton焦虑量表 (HAMA)总分在治疗结束时均显著下降 (P <0 0 0 1)。两组之间疗效无显著差异 (p >0 0 5 )。治疗结束时HAMD减分率分别为吗氯贝胺组 0 74± 0 2 4,米帕明组 0 74± 0 2 4(P >0 0 5 ) ;有效率吗氯贝胺组 79 4% ,米帕明组 85 4% (P >0 0 5 )。吗氯贝胺组有 10种不良反应发生频率显著低于米帕明组 ,主要是抗胆碱能、中枢神经系统及心血管系统不良反应。吗氯贝胺的疗效指数也显著高于米帕明组。结论 :吗氯贝胺是一种安全有效的抗抑郁药物     

Pancreatic solid pseudopapillary neoplasm

Pancreatic solid pseudopapillary neoplasm (SPN) is a rare low grade malignant tumour. Distinguishing this entity from other pancreatic neoplasms is critical for therapeutic decision making and prognostication. It predominantly affects young female patients <40 years of age, with excellent clinical outcome following surgical removal. The gold standard diagnostic test is cytopathological or histopathological assessment of fine needle aspirate. There are two main difficulties with this. First, SPN can present with morphological and immunohistochemical appearances that can closely mimic other pancreatic tumours, in particular, pancreatic neuroendocrine tumour (NET). Second, the amount of diagnostic material from fine needle aspiration can be limited. Here, we present a cytopathological case with both challenges during the pre-operative investigation of SPN. The case exemplifies the importance of combining morphological features with a targeted panel of immunohistochemistry to arrive at the diagnosis.     

A Theoretical Model for the Margination of Particles within Blood Vessels

The margination of a particle circulating in the blood stream has been analyzed. The contribution of buoyancy, hemodynamic forces, van der Waals, electrostatic and steric interactions between the circulating particle and the endothelium lining the vasculature has been considered. For practical applications, the contribution of buoyancy, hemodynamic forces and van der Waals interactions should be only taken into account, whilst the effect of electrostatic and steric repulsion becomes important only at very short distances from the endothelium (1–10 nm). The margination speed and the time for margination t_s have been estimated as a function of the density of the particle relative to blood , the Hamaker constant A and radius R of the particle. A critical radius R_c exists for which the margination time t_s has a maximum, which is influenced by both and A: the critical radius decreases as the relative density increases and the Hamaker constant decreases. Therefore, particles used for drug delivery should have a radius smaller than the critical value (in the range of 100 nm) to facilitate margination and interaction with the endothelium. While particles used as nanoharvesting agents in proteomics or genomics analysis should have a radius close to the critical value to minimize margination and increase their circulation time.