Corneal conjunctivalisation in long‐standing contact lens wearers

Background: There are many contact lens‐related ocular surface disorders. Some can damage the limbal region where stem cells are thought to be located in its basal cell layer. This damage can result in destruction and a deficiency of corneal stem cells. One important sign of this complication is corneal conjunctivalisation. The purpose of this study is to describe clinical characteristics of a series of long‐standing contact lens (CL) wearers with corneal conjunctivalisation (CC). Methods: In a one‐year (March 2004 to March 2005) retrospective unmasked study, 591 CL clinical histories (195 new patients and 396 review patients) were analysed. Results: There were 24 eyes of 14 myopic patients (93 per cent women) with CC without a specific disease entity known to cause limbal stem cell deficiency (LSCD). Conjunctivalisation occurred in the inferior limbus of three eyes (12 per cent). Only four patients (28.6 per cent) reported previous ocular symptoms. All were myopic with a mean spherical equivalent of ‐8.80 ± 5.00 (SD) dioptres (range from ‐1.75 to ‐21.50 D) and mean visual acuity 0.9 ± 0.2 (range from 0.4 to 1.2). The mean years of CL wear was 17.6 ± 8.5 (CI 95% 13.2 to 22; range six to 30). All were daily‐wear patients with a mean daily‐wear time of 12.5 ± 1.8 hours per day (CI 95% 11.6 to 13.4). Conclusion: Corneal conjunctivalisation is a contact lens‐related complication in asymptomatic patients. Optometrists can play an important role in early diagnosis, education and management of these patients.     

Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers

Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention.     

Mortality among ferrous foundry workers

Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies.     

Lhermitte-Duclos disease

Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum) is a rare pseudo-neoplastic disorder of the cerebellum with typical MRI findings. A 25-year-old man presenting with progressive neck pain, dizziness, and impaired vision is reported. CT and MRI revealed a left cerebellar haemispheric mass and obstructive hydrocephalus. Lhermitte-Duclos disease was histologically confirmed after surgical removal of the lesion. The typical MRI appearance of a nonenhancing haemispheric cerebellar mass with preservation and exaggeration of the normal gyral pattern allows pre-operative diagnosis of this condition. The literature is reviewed and clinical presentation, radiology and histopathology are discussed.     

糖尿病增大无症状心肌缺血发生率

用常规心电图及动态心电图监测的方法，分别观察３０例糖尿病人和３０例非糖尿病人无症状心肌缺血的发生率。发现无症状心肌缺血在糖尿病组显著高于非糖尿病组（Ｐ〈０．０５），部分糖尿病人有严重心肌缺血却无胸痛症状，可能与其植物神经功能损害引起痛阈提高、血中内啡肽水平增高导致痛觉敏感性下降有关，用动态心电图监测可提高无症状心肌缺血的检出率。     

Is There an Advantage to Repairing Infected Mitral Valves?

Background. The therapy for native mitral valve endocarditis is in evolution. Antibiotics have significantly improved survival rates, but patients with complications of endocarditis may require surgical treatment.

Methods. Between January 1985 and December 1995, 146 patients underwent surgical therapy (repair or replacement) for native mitral valve endocarditis. All patients had documented bacterial endocarditis. Univariate and multivariate analyses were performed to determine predictors of hospital death, long-term event-free survival, and probability of repair. Patients were evaluated in three groups: all patients, patients with acute endocarditis, and patients with chronic endocarditis.

Results. There were ten hospital deaths (6.8%). Patients undergoing repair had a lower hospital mortality rate (p = 0.008) then those having replacement. Event-free survival was improved after mitral valve repair in the overall group (p = 0.02) and in the group with healed (chronic) endocarditis (p = 0.05). Although the acute endocarditis group demonstrated an improved event-free survival rate after mitral valve repair versus replacement (74% versus 20% at 6 years), this did not reach statistical significance.

Conclusions. We conclude that mitral valve repair is preferable to mitral valve replacement when possible, in patients with complications of endocarditis, as repair results in a lower hospital mortality and an improved long-term survival.     

军团菌肺炎的临床特点探讨

作者对１０例军团菌肺炎和１０例非军团菌肺炎患者临床资料进行分析。本组军团菌肺炎特点为：病情重、进展快、消化道症状及肌肉关节痛、低钠血症、低氧血症、代酸或呼碱发生率较高，Ｘ线胸片多见双侧或多叶肺浸润伴胸膜反应，病死率高。     

蝮蛇抗栓酶治疗缺血性脑血管病的甲襞微循环及血液流变性观察

对使用蝮蛇抗栓酶、维脑路通的缺血性脑血管病患者各５０例进行甲襞微循环和血液流变指标的检测。结果表明：蝮蛇抗栓酶组用药后，微循环和血液流变各项异常指标显著下降（Ｐ＜０．０１～０．０５）。而维脑路通对脑血栓的微循环障碍、血液粘度、β－脂蛋白、甘油三酯、血小板聚集等异常指标改善不大（Ｐ＞０．０５）。提示：蝮蛇抗栓酶是优于维脑路通的降粘药物。     

Distribution of α-integrin subunits in fetal polycystic kidney diseases

An alteration in cell/matrix interactions is one of the suggested mechanisms leading to cyst formation in polycystic kidney diseases. Most of these interactions are mediated by β1-integrins, a subfamily of integrin receptors, formed by the association of the β1-chain with different α-subunits. To date, no study on α-integrin subunit distribution during the early stages of cyst development has been reported. Using immunofluorescence, we analyzed the distribution of α-integrin subunits (α1, α2, α3, α5, and α6) and basement membrane proteins in kidneys of fetuses with autosomal dominant (ADPKD) or autosomal recessive polycystic kidney disease (ARPKD). The distribution was compared with that observed in normal fetal and post-natal kidneys, and in fetal cystic dysplasia and Meckel syndrome. Marked increase in α1-integrin staining was observed in normal and cystic collecting duct cells of both polycystic diseases (PKD), compared with normal and cystic controls. The distribution of integrin subunits α2, α3, and α6 was irregular in cyst epithelial cells of PKD and cystic controls. The increased expression of the α1-subunit specifically observed in PKD collecting duct cells may be an early consequence of the genetic defect in ARPKD. In ADPKD it parallels the reported expression of polycystin, the protein product of PKD1. The irregular expression of α2, α3, and α6 integrin subunits observed in all types of cysts suggests that cell/matrix interactions are altered early and may participate in the development of cysts, perhaps by contributing to the deregulation of cell survival in cystic diseases. Received May 28, 1996; received in revised form October 2, 1996; accepted October 25, 1996     

Magnetization transfer imaging of multiple sclerosis

While conventional magnetic resonance imaging (MRI) measures signal primarily from the hydrogen nuclei of water, magnetization transfer (MT) MRI indirectly detects macromolecular associated hydrogen nuclei via their magnetic interaction with the observable water. In the normal adult CNS, white matter exhibits the largest MT effect due to the macromolecular content of the highly structured and lipid rich myelin. Pathologies which alter the structural integrity and the relative macromolecular-water composition, such as multiple sclerosis (MS), therefore show abnormal MT. Conventional MRI, which has a high MS lesion detection sensitivity but poor specificity in terms of differentiating the pathological state of a plaque, can thus be supplemented by MT to provide more specific information on the extent of demyelination and axonal loss. In this paper we review the basic concepts of MT imaging and its role in MS lesion characterization.Financial support was provided by the Medical Research Council of Canada, Fonds de la Recherche en Santé du Québec, and the Killam Foundation.