Complications in Intermediate Uveitis: Prevalence,Time of Onset,and Effects on Vision in Short-Term and Long-Term Follow-Up

Purpose: To study the prevalence and time of onset of ocular complications in intermediate uveitis (IU) and to assess their effects on visual outcome in short-term and long-term follow-up.

Methods: A retrospective cohort study of patients with IU who had a minimal follow-up of one year.

Results: 96 patients (174 eyes, 70% females) were included with a mean age at presentation of 30 years. Children constituted 38% of all patients. Mean follow- up was 64.9 months. Pars planitis was the most common form followed by sarcoidosis and multiple sclerosis. Cystoid macular edema (CME), cataract, epiretinal membrane and posterior synechiae were the most prevalent complications. Posterior synechiae, band keratopathy, cataract and papillitis at presentation were associated with worse presenting visual acuity (VA). Of the late-onset complications, glaucoma/ocular hypertension (OHT) was the most significantly associated with worse long-term VA. Most sight-threatening complications (namely CME and glaucoma) were diagnosed at presentation while late complications predominantly affected the posterior segment and included among others peripheral retinal elevations, vasoproliferative tumors, and vitreous hemorrhage. Median LogMAR VA improved at short-term and long-term follow-up, from 0.2 to 0.1 (p<0.001). Subgroup analysis revealed significant VA improvement for eyes with all the different complications except for eyes with glaucoma/OHT.

Conclusion: IU is a chronic low-grade uveitis that may be associated with protean early and late complications of the anterior or posterior segments or both. Optimal treatment regimens are imperative for the strict control of inflammation and proper management of complications thus allowing a favorable long-term prognosis.     

Changes in glial fibrillary acidic protein mRNA expression after corticospinal axotomy in the adult hamster

We examined changes in the expression of glial fibrillary acidic protein (GFAP) mRNA during Wallerian degeneration in the corticospinal system of the adult Golden hamster following axotomy. GFAP is the product of a type III intermediate filament (IF) gene that is expressed specifically in mature astrocytes. A well-studied component of a complex response termed reactive astrogliosis that occurs after various types of CNS injury is the increased production of astrocytic processes filled with GFAP-containing IFs. While increased expression of GFAP during reactive astrogliosis has been well established at the protein level, little is known about whether or not changes in GFAP mRNA levels occur after CNS injury. In the present study we used in situ hybridization methods to examine this issue. A 35S-labeled mouse GFAP cDNA probe was used for in situ hybridizations of sections of the brain stem obtained 2, 7, and 14 days after unilateral transections of the corticospinal tract in the caudal medulla. Film as well as emulsion autoradiography showed a dramatic increase in GFAP mRNA labeling associated with the degenerating corticospinal tract. GFAP mRNA levels were already dramatically increased in the injured corticospinal tract by 2 days post axotomy and remained elevated at 14 days. Interestingly, in addition to the robust increase in GFAP mRNA levels specifically associated with the degenerating tract, a diffuse increase in GFAP mRNA labeling was observed throughout the grey matter of the brain stem at 2 days post-axotomy, but not after this time. Immunoblotting and immunocytochemical experiments verified that the increased GFAP mRNA levels in the degenerating corticospinal system were accompanied by an increased expression of the protein. These results demonstrate that an increase in GFAP mRNA levels occurs during Wallerian degeneration in the CNS and suggest that increased expression of the GFAP gene is a major contributor to CNS scarring that results after direct traumatic injury.     

Primary Alloproliferative TH1 Response Induced by Immature Plasmacytoid Dendritic Cells in Collaboration with Myeloid DCs

The role played by dendritic cell (DC) subsets in the immune response to alloantigens is not well defined. In vitro experiments have extensively shown that freshly isolated myeloid (M)DCs induce a strong T lymphocyte proliferation whereas plasmacytoid (P)DCs do not, unless activated by CD40 ligation. The aim of these studies was to explore whether the interplay among PDCs, MDCs and T cells modulates alloresponse. Freshly isolated MDCs and PDCs were merged in different proportions and used as antigen presenting cells (APCs) in mixed lymphocyte cultures (MLC). As described, isolated PDCs only induced a mild alloresponse, while MDCs were potent inducers of alloproliferation. Unexpectedly, when PDCs were merged with even low numbers of MDCs (down to 100 cells) and used as APCs, a potent Th1 cell proliferation was detected. Survival and maturation of PDCs was increased in these MLC conditions, which could partially explain the magnitude of the T-cell response. Interestingly, the proportion of IFNgamma-producing cells generated in such cultures was higher compared to MDC-stimulated cultures. These data suggest that the interaction between both DC subsets is determinant to generate a potent Th1 response, at least in an allogeneic situation, and may be relevant to the outcome of allogeneic stem cell transplantation.     

Stability of subtilisins and related proteinases (subtilases)

The stability towards thermal and chemical (guanidine hydrochloride, GnHCl) denaturation of six inhibited subtilases (mesentericopeptidase, subtilisins BPN′, Carlsberg and DY, proteinase K and thermitase) has been investigated by kinetic and equilibrium studies. The unfolding processes were monitored by circular dichroic and fluorescence spectroscopy. Experiments in the absence and presence of extraneous calcium in the concentration range 2×10^?3-10^?1 M were performed. The presence of calcium in the weak calcium binding site changes the denaturation drastically. The heat- (or GnHCl-) induced unfolding curves obtained using CD spectroscopy show two independent transitions which seem not to have been resolved before. The presence of Ca²⁺ in the second (third in the case of thermitase) binding site increases the T_m, values by 11-21 °C and the δG_D(H₂O) values obtained from denaturation experiments in GnHCl by 6.7-7.2 kcal/mol when an extraneous Ca²⁺ concentration of 2 × 10^?2 M was used. One interpretation is that the initial step of denaturation in the presence of added calcium is the formation of a partially unfolded intermediate form, retaining a highly ordered structure with 60-85% of the a-helix structure of the native enzyme. This intermediate then unfolds at a temperature considerably higher than that of the same proteinases in the absence of added Ca²⁺. The free energy of stabilization of the intermediates is increased by 1.8-2.8 times in comparison with that for the unfolding reactions of the subtilases with empty Ca2/Ca3 binding sites. A second interpretation is that the two steps in the unfolding curves correspond to enzyme without and with calcium in the weak binding site. Fluorescence experiments confirm the mechanism involving the formation of intermediate states. The results are discussed in relation to the X-ray models of the six subtilases.     

Contraception and sexually transmitted diseases: Interactions and opportunities

Today "safe sex" means protection from both unintended pregnancy and sexually transmitted disease and human immunodeficiency virus. These parallel complications of sexual activity have serious biologic and clinical sequelae that should be considered at the time of contraceptive selection. In addition, there is ongoing debate regarding potential interactions between antibiotic intervention and contraceptive steroids. This article assesses the impact of hormonal contraception, spermicides, barrier methods, intrauterine devices, and douching on the pathogenesis of sexually transmitted disease and the human immunodeficiency virus infection. It discusses the direct and indirect effects of contraception methods on clinical physiology and host immune responses while also considering the possible consequences on maternal and infant health if pregnancy results from the use of ineffective contraception. Counseling and care for both family planning and infectious disease protection must be provided to all sexually active individuals. (Ann J OBSTET GVNECOL 1993;168:2033-41.)     

造血干细胞移植后慢性移植物抗宿主病相关的膜性肾病一例

目的 总结造血干细胞移植后慢性移植物抗宿主病（cGVHD）相关的膜性肾病的诊疗体会。方法 为1例急性淋巴细胞白血病患者施行HLA全相合的无关供者外周血造血干细胞移植，术后应用甲氨喋呤和他克莫司（FK506）预防GVHD。术后第19d发生急性GVHD，经甲泼尼龙治疗逆转。分别于术后182d、235d停用FK506和泼尼松，5d后患者出现cGVHD表现，肝功能异常，并伴肾病综合征的相关表现，病理诊断为膜性肾病Ⅱ期，遂给予FK506和泼尼松治疗，同时辅以利尿、降脂等措施。结果发生膜性肾病时，患者的尿蛋白＋＋＋＋，白细胞75个／μl，上皮细胞359．5个／pl，病理性管型＋，管型计数为167个／μl，24h尿蛋白定量为4．28g；肾组织活检，无肾小球硬化，肾小球体积稍大，部分血管袢受压，开放欠佳，肾小球基底膜轻微增厚，外观呈僵硬感，系膜基质轻、中度增殖；间质区部分肾小管扩张，肿胀、变性，未见明显间质纤维化和炎症细胞浸润；Masson染色可见基底膜上皮侧嗜复红物沉积；免疫荧光检查，IgG＋＋＋，C3＋＋＋，IgA＋＋，沿毛细血管袢呈颗粒状节段性分布，系膜区呈团块状分布；IgM、Clq、CA均阴性。电镜下可见肾小球基底膜上皮下沉积物，并有基膜增厚，毛细血管系膜基质轻度增生。经泼尼松和FK506治疗，2个月后尿蛋白转阴。结论 造血干细胞移植后出现肾病综合征或蛋白尿，应考虑GVHD相关膜性肾病的可能，肾穿刺活检有助于诊断，糖皮质激素和FK506治疗有效。     

Liver regeneration in acute severe liver impairment: a clinicopathological correlation study.

BACKGROUND: Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injury. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired, hepatic progenitor cells (HPCs) are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells generate new hepatocytes and biliary cells to restore liver homeostasis. AIMS/METHODS: To study the relationship between different histopathological parameters as well as their correlations with clinical parameters and outcome, we examined liver specimens from 74 patients with acute or subacute severe liver impairment by immunohistochemistry for CK7/CK19 (evaluation of HPCs activation/differentiation), Mib1(Ki 67)/P21 (evaluation of proliferative activity/proliferation arrest of hepatocytes) and hematoxylin and eosin (evaluation of hepatocyte loss). RESULTS: Of the 74 patients, 32% survived without transplantation, 14% died without transplantation and 54% were transplanted. Our results show that a threshold of 50% loss of hepatocytes, associated with significant decrease in the proliferative activity of remaining mature hepatocytes, is needed for extensive hepatic progenitor cell activation. Such activation is a sign of disease severity and occurs early (within 1 week) in the disease course. However, development of intermediate hepatocytes, suggesting HPCs differentiation towards mature hepatocytes, takes at least 1 week's time. We found a positive correlation between histopathological parameters (percentage hepatocyte loss, number of proliferating hepatocytes and number of HPCs) and clinical parameters of liver impairment such as model for end stage liver diseases (MELD). Surviving patients compared with those who either died or were transplanted had significantly less hepatocyte loss, less HPCs activation and more mature hepatocyte proliferative activity. Hepatocyte proliferative activity and degree of hepatocyte loss were the most important independent histopathological parameters in predicting outcome. CONCLUSION: Liver biopsy can provide important additional information in a patient with severe acute liver impairment.