Immunologic heterogeneity of diffuse large cell lymphoma

The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.     

The immunohistology of follicle lysis in lymph node biopsies from homosexual men

Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.     

Evidence for active synapse formation or altered postsynaptic metabolism in visual cortex of rats reared in complex environments.

Animals placed in complex environments develop greater numbers of visual cortex synapses per neuron than animals housed in standard cages. Increased numbers of synapses could theoretically arise from (i) active formation of new synapses, or (ii) selective stabilization of constitutively produced synapses. The postsynaptic location of polyribosomal aggregates appears to be an indicator of newly forming synapses. In developmental synaptogenesis and adult reactive (to injury) synaptogenesis, polyribosomes are more frequently found at spine synapses and are more likely to appear in the spine head and stem. In the visual cortex of rats from complex environments, there was a greater frequency of spine synapses associated with polyribosomes, relative to rats from individual or group cages. Furthermore, a greater percentage of these spines had polyribosomes in the head and stem region. This suggests that synapses in this region may be actively induced by neural activity arising from the complex environment experience.     

电视腹腔镜外科手术在胃肠道肿瘤的临床应用

目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术１８例,其中右半结肠切除术４例,横结肠癌根治术３例,乙状结肠癌根治术５例,乙状结肠癌姑息切除术并肝转移癌电凝固化１例,胃癌术后复发转移行探查活检１例,胃巨大恶性淋巴瘤行探查活检１例,晚期回肠癌行小肠侧侧吻合术１例,乙状结肠腺瘤切除术２例。结果均获成功,无中转开腹,手术时间平均１６５．０分钟。术后平均３１．２小时胃肠功能恢复,无并发症发生,术后平均住院８．２天。１３例切除肿瘤的结肠癌术后随访２月～３０月,仅１例横结肠癌术后２３月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。     

Management of ductal carcinoma in situ

The dramatic increase in the incidence of ductal carcinoma in situ (DCIS) of the breast has made it imperative for all clinicians to develop a better understanding of this disease. Although this preinvasive form of breast cancer is not life-threatening, treatment options may include mastectomy, breast-conserving surgery, radiotherapy, or tamoxifen. Current treatment modalities may be overly aggressive because many cases of DCIS may not recur or progress to invasive cancer. Until we are better able to identify those patients at low risk for progression, it is unlikely that current treatment will change. The adequate understanding of risk assessment is fundamental to the treatment planning for DCIS, and physicians are encouraged to include patients in the decision-making process.     

Laparoscopic appendectomy in young female patients: Should we remove the normal-looking appendix?

Objective : This study evaluated whether a significant reduction in unnecessary appendectomies is possible by performing diagnostic laparoscopy before appendectomy in female patients of child-bearing age, leaving behind the normal-looking appendix. Materials and methods : Sixty-one consecutive female patients between the ages of 15 and 45 years with clinical diagnosis of acute appendicitis were studied prospectively. Diagnostic laparoscopy was performed to detect whether the appendix was inflamed. The appendix was then removed and the result of laparoscopic diagnosis was matched with histological diagnosis. Results : Ten out of the 42 laparoscopically diagnosed appendicitis cases had normal appendices on histological examination. Six out of the 19 laparoscopically diagnosed normal appendices had histological evidence of appendicitis. The sensitivity of laparoscopy was 84% and the specificity was 56.5%. Conclusions : Discrepancies existed between laparoscopic appearance and histological examination in acute appendicitis. The appendices of all those with clinically suspected appendicitis should be removed and sent for histological confirmation.